[v2,1/9] PM: domains: Delete usage of driver_deferred_probe_check_state()

Commit Message

Saravana Kannan June 1, 2022, 7:06 a.m. UTC

Now that fw_devlink=on by default and fw_devlink supports
"power-domains" property, the execution will never get to the point
where driver_deferred_probe_check_state() is called before the supplier
has probed successfully or before deferred probe timeout has expired.

So, delete the call and replace it with -ENODEV.

Signed-off-by: Saravana Kannan <[e-mail]>
---
 drivers/base/power/domain.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Ulf Hansson June 9, 2022, 11:44 a.m. UTC | #1

On Wed, 1 Jun 2022 at 09:07, Saravana Kannan <[e-mail]> wrote:
>
> Now that fw_devlink=on by default and fw_devlink supports
> "power-domains" property, the execution will never get to the point
> where driver_deferred_probe_check_state() is called before the supplier
> has probed successfully or before deferred probe timeout has expired.
>
> So, delete the call and replace it with -ENODEV.

With fw_devlink=on by default - does that mean that the parameter
can't be changed?

Or perhaps the point is that we don't want to go back, but rather drop
the fw_devlink parameter altogether when moving forward?

>
> Signed-off-by: Saravana Kannan <[e-mail]>

Just a minor nitpick below. Nevertheless, feel free to add:

Reviewed-by: Ulf Hansson <[e-mail]>

> ---
>  drivers/base/power/domain.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> index 739e52cd4aba..3e86772d5fac 100644
> --- a/drivers/base/power/domain.c
> +++ b/drivers/base/power/domain.c
> @@ -2730,7 +2730,7 @@ static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
>                 mutex_unlock(&gpd_list_lock);
>                 dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
>                         __func__, PTR_ERR(pd));
> -               return driver_deferred_probe_check_state(base_dev);

Adding a brief comment about why -EPROBE_DEFER doesn't make sense
here, would be nice.

> +               return -ENODEV;
>         }
>
>         dev_dbg(dev, "adding to PM domain %s\n", pd->name);
> --
> 2.36.1.255.ge46751e96f-goog
>

Kind regards
Uffe

Saravana Kannan June 9, 2022, 7:29 p.m. UTC | #2

On Thu, Jun 9, 2022 at 4:45 AM Ulf Hansson <[e-mail]> wrote:
>
> On Wed, 1 Jun 2022 at 09:07, Saravana Kannan <[e-mail]> wrote:
> >
> > Now that fw_devlink=on by default and fw_devlink supports
> > "power-domains" property, the execution will never get to the point
> > where driver_deferred_probe_check_state() is called before the supplier
> > has probed successfully or before deferred probe timeout has expired.
> >
> > So, delete the call and replace it with -ENODEV.
>
> With fw_devlink=on by default - does that mean that the parameter
> can't be changed?
>
> Or perhaps the point is that we don't want to go back, but rather drop
> the fw_devlink parameter altogether when moving forward?

Good question. For now, keeping fw_devlink=off and
fw_devlink=permissive as debugging options that I can ask people to
try if some probe is getting blocked.

Or maybe if some ultra low memory use case wants to avoid create
device links, fwnode links, etc and can build everything in and have
init/probe happen in the right order.

But in the long run, I see a strong possibility for
fw_devlink=off/permissive being removed. I'd still want to keep it for
implementing =rpm where it'd also automatically enable PM runtime
tracking, but I don't understand that well enough yet to do it by
default.

> >
> > Signed-off-by: Saravana Kannan <[e-mail]>
>
> Just a minor nitpick below. Nevertheless, feel free to add:
>
> Reviewed-by: Ulf Hansson <[e-mail]>

Thanks!

>
> > ---
> >  drivers/base/power/domain.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> > index 739e52cd4aba..3e86772d5fac 100644
> > --- a/drivers/base/power/domain.c
> > +++ b/drivers/base/power/domain.c
> > @@ -2730,7 +2730,7 @@ static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
> >                 mutex_unlock(&gpd_list_lock);
> >                 dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
> >                         __func__, PTR_ERR(pd));
> > -               return driver_deferred_probe_check_state(base_dev);
>
> Adding a brief comment about why -EPROBE_DEFER doesn't make sense
> here, would be nice.

Will do once all the reviews comeout/when I send v3.

I'm thinking something like:
/* fw_devlink will take care of retrying for missing suppliers */

-Saravana

>
> > +               return -ENODEV;
> >         }
> >
> >         dev_dbg(dev, "adding to PM domain %s\n", pd->name);
> > --
> > 2.36.1.255.ge46751e96f-goog
> >
>
> Kind regards
> Uffe

Tony Lindgren June 21, 2022, 7:28 a.m. UTC | #3

Hi,

* Saravana Kannan <[e-mail]> [700101 02:00]:
> Now that fw_devlink=on by default and fw_devlink supports
> "power-domains" property, the execution will never get to the point
> where driver_deferred_probe_check_state() is called before the supplier
> has probed successfully or before deferred probe timeout has expired.
> 
> So, delete the call and replace it with -ENODEV.

Looks like this causes omaps to not boot in Linux next. With this
simple-pm-bus fails to probe initially as the power-domain is not
yet available. On platform_probe() genpd_get_from_provider() returns
-ENOENT.

Seems like other stuff is potentially broken too, any ideas on
how to fix this?

Regards,

Tony



> 
> Signed-off-by: Saravana Kannan <[e-mail]>
> ---
>  drivers/base/power/domain.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> index 739e52cd4aba..3e86772d5fac 100644
> --- a/drivers/base/power/domain.c
> +++ b/drivers/base/power/domain.c
> @@ -2730,7 +2730,7 @@ static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
>  		mutex_unlock(&gpd_list_lock);
>  		dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
>  			__func__, PTR_ERR(pd));
> -		return driver_deferred_probe_check_state(base_dev);
> +		return -ENODEV;
>  	}
>  
>  	dev_dbg(dev, "adding to PM domain %s\n", pd->name);
> -- 
> 2.36.1.255.ge46751e96f-goog
>

Saravana Kannan June 21, 2022, 7:34 p.m. UTC | #4

On Tue, Jun 21, 2022 at 12:28 AM Tony Lindgren <[e-mail]> wrote:
>
> Hi,
>
> * Saravana Kannan <[e-mail]> [700101 02:00]:
> > Now that fw_devlink=on by default and fw_devlink supports
> > "power-domains" property, the execution will never get to the point
> > where driver_deferred_probe_check_state() is called before the supplier
> > has probed successfully or before deferred probe timeout has expired.
> >
> > So, delete the call and replace it with -ENODEV.
>
> Looks like this causes omaps to not boot in Linux next.

Can you please point me to an example DTS I could use for debugging
this? I'm assuming you are leaving fw_devlink=on and not turning it
off or putting it in permissive mode.

> With this
> simple-pm-bus fails to probe initially as the power-domain is not
> yet available.

Before we get to late_initcall(), I'd expect this series to not have
any impact because both fw_devlink and
driver_deferred_probe_check_state() should be causing the device's
probe to get deferred until the PM domain device comes up.

To double check this, without this series, can you give me the list of
"supplier:*" symlinks under a simple-pm-bus device's sysfs folder
that's having problems with this series? And for all those symlinks,
cat the "status" file under that directory?

In the system where this is failing, is the PM domain driver loaded as
a module at a later point?

Couple of other things to try (with the patches) to narrow this down:
* Can you set driver_probe_timeout=0 in the command line and see if that helps?
* Can you set it to something high like 30 or even larger and see if it helps?

> On platform_probe() genpd_get_from_provider() returns
> -ENOENT.

This error is with the series I assume?

> Seems like other stuff is potentially broken too, any ideas on
> how to fix this?

I'll want to understand the issue first. It's not yet clear to me why
fw_devlink isn't blocking the probe of the simple-pm-bus device until
the PM domain device shows up. And if it is not blocking, then why and
at what point in boot it's giving up and letting the probe get to this
point where there's an error.

-Saravana

>
>
> >
> > Signed-off-by: Saravana Kannan <[e-mail]>
> > ---
> >  drivers/base/power/domain.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> > index 739e52cd4aba..3e86772d5fac 100644
> > --- a/drivers/base/power/domain.c
> > +++ b/drivers/base/power/domain.c
> > @@ -2730,7 +2730,7 @@ static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
> >               mutex_unlock(&gpd_list_lock);
> >               dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
> >                       __func__, PTR_ERR(pd));
> > -             return driver_deferred_probe_check_state(base_dev);
> > +             return -ENODEV;
> >       }
> >
> >       dev_dbg(dev, "adding to PM domain %s\n", pd->name);
> > --
> > 2.36.1.255.ge46751e96f-goog
> >
>
> --
> To unsubscribe from this group and stop receiving emails from it, send an email to [e-mail].
>

Tony Lindgren June 22, 2022, 4:58 a.m. UTC | #5

Hi,

* Saravana Kannan <[e-mail]> [220621 19:29]:
> On Tue, Jun 21, 2022 at 12:28 AM Tony Lindgren <[e-mail]> wrote:
> >
> > Hi,
> >
> > * Saravana Kannan <[e-mail]> [700101 02:00]:
> > > Now that fw_devlink=on by default and fw_devlink supports
> > > "power-domains" property, the execution will never get to the point
> > > where driver_deferred_probe_check_state() is called before the supplier
> > > has probed successfully or before deferred probe timeout has expired.
> > >
> > > So, delete the call and replace it with -ENODEV.
> >
> > Looks like this causes omaps to not boot in Linux next.
> 
> Can you please point me to an example DTS I could use for debugging
> this? I'm assuming you are leaving fw_devlink=on and not turning it
> off or putting it in permissive mode.

Sure, this seems to happen at least with simple-pm-bus as the top
level interconnect with a configured power-domains property:

$ git grep -A10 "ocp {" arch/arm/boot/dts/*.dtsi | grep -B3 -A4 simple-pm-bus

This issue is no directly related fw_devlink. It is a side effect of
removing driver_deferred_probe_check_state(). We no longer return
-EPROBE_DEFER at the end of driver_deferred_probe_check_state().

> > On platform_probe() genpd_get_from_provider() returns
> > -ENOENT.
> 
> This error is with the series I assume?

On the first probe genpd_get_from_provider() will return -ENOENT in
both cases. The list is empty on the first probe and there are no
genpd providers at this point.

Earlier with driver_deferred_probe_check_state(), the initial -ENOENT
ends up getting changed to -EPROBE_DEFER at the end of
driver_deferred_probe_check_state(), we are now missing that.

Regards,

Tony

Saravana Kannan June 22, 2022, 7:09 p.m. UTC | #6

On Tue, Jun 21, 2022 at 9:59 PM Tony Lindgren <[e-mail]> wrote:
>
> Hi,
>
> * Saravana Kannan <[e-mail]> [220621 19:29]:
> > On Tue, Jun 21, 2022 at 12:28 AM Tony Lindgren <[e-mail]> wrote:
> > >
> > > Hi,
> > >
> > > * Saravana Kannan <[e-mail]> [700101 02:00]:
> > > > Now that fw_devlink=on by default and fw_devlink supports
> > > > "power-domains" property, the execution will never get to the point
> > > > where driver_deferred_probe_check_state() is called before the supplier
> > > > has probed successfully or before deferred probe timeout has expired.
> > > >
> > > > So, delete the call and replace it with -ENODEV.
> > >
> > > Looks like this causes omaps to not boot in Linux next.
> >
> > Can you please point me to an example DTS I could use for debugging
> > this? I'm assuming you are leaving fw_devlink=on and not turning it
> > off or putting it in permissive mode.
>
> Sure, this seems to happen at least with simple-pm-bus as the top
> level interconnect with a configured power-domains property:
>
> $ git grep -A10 "ocp {" arch/arm/boot/dts/*.dtsi | grep -B3 -A4 simple-pm-bus

Thanks for the example. I generally start looking from dts (not dtsi)
files in case there are some DT property override/additions after the
dtsi files are included in the dts file. But I'll assume for now
that's not the case. If there's a specific dts file for a board I can
look from that'd be helpful to rule out those kinds of issues.

For now, I looked at arch/arm/boot/dts/omap4.dtsi.

>
> This issue is no directly related fw_devlink. It is a side effect of
> removing driver_deferred_probe_check_state(). We no longer return
> -EPROBE_DEFER at the end of driver_deferred_probe_check_state().

Yes, I understand the issue. But driver_deferred_probe_check_state()
was deleted because fw_devlink=on should have short circuited the
probe attempt with an  -EPROBE_DEFER before reaching the bus/driver
probe function and hitting this -ENOENT failure. That's why I was
asking the other questions.

> > > On platform_probe() genpd_get_from_provider() returns
> > > -ENOENT.
> >
> > This error is with the series I assume?
>
> On the first probe genpd_get_from_provider() will return -ENOENT in
> both cases. The list is empty on the first probe and there are no
> genpd providers at this point.
>
> Earlier with driver_deferred_probe_check_state(), the initial -ENOENT
> ends up getting changed to -EPROBE_DEFER at the end of
> driver_deferred_probe_check_state(), we are now missing that.

Right, I was aware -ENOENT would be returned if we got this far. But
the point of this series is that you shouldn't have gotten that far
before your pm domain device is ready. Hence my questions from the
earlier reply.

Can I get answers to rest of my questions in the first reply please?
That should help us figure out why fw_devlink let us get this far.
Summarize them here to make it easy:
* Are you running with fw_devlink=on?
* Is the"ti,omap4-prm-inst"/"ti,omap-prm-inst" built-in in this case?
* If it's not built-in, can you please try deferred_probe_timeout=0
and deferred_probe_timeout=30 and see if either one of them help?
* Can I get the output of "ls -d supplier:*" and "cat
supplier:*/status" output from the sysfs dir for the ocp device
without this series where it boots properly.

Thanks,
Saravana

Tony Lindgren June 23, 2022, 7:01 a.m. UTC | #7

* Saravana Kannan <[e-mail]> [220622 19:05]:
> On Tue, Jun 21, 2022 at 9:59 PM Tony Lindgren <[e-mail]> wrote:
> >
> > Hi,
> >
> > * Saravana Kannan <[e-mail]> [220621 19:29]:
> > > On Tue, Jun 21, 2022 at 12:28 AM Tony Lindgren <[e-mail]> wrote:
> > > >
> > > > Hi,
> > > >
> > > > * Saravana Kannan <[e-mail]> [700101 02:00]:
> > > > > Now that fw_devlink=on by default and fw_devlink supports
> > > > > "power-domains" property, the execution will never get to the point
> > > > > where driver_deferred_probe_check_state() is called before the supplier
> > > > > has probed successfully or before deferred probe timeout has expired.
> > > > >
> > > > > So, delete the call and replace it with -ENODEV.
> > > >
> > > > Looks like this causes omaps to not boot in Linux next.
> > >
> > > Can you please point me to an example DTS I could use for debugging
> > > this? I'm assuming you are leaving fw_devlink=on and not turning it
> > > off or putting it in permissive mode.
> >
> > Sure, this seems to happen at least with simple-pm-bus as the top
> > level interconnect with a configured power-domains property:
> >
> > $ git grep -A10 "ocp {" arch/arm/boot/dts/*.dtsi | grep -B3 -A4 simple-pm-bus
> 
> Thanks for the example. I generally start looking from dts (not dtsi)
> files in case there are some DT property override/additions after the
> dtsi files are included in the dts file. But I'll assume for now
> that's not the case. If there's a specific dts file for a board I can
> look from that'd be helpful to rule out those kinds of issues.
> 
> For now, I looked at arch/arm/boot/dts/omap4.dtsi.

OK it should be very similar for all the affected SoCs.

> > This issue is no directly related fw_devlink. It is a side effect of
> > removing driver_deferred_probe_check_state(). We no longer return
> > -EPROBE_DEFER at the end of driver_deferred_probe_check_state().
> 
> Yes, I understand the issue. But driver_deferred_probe_check_state()
> was deleted because fw_devlink=on should have short circuited the
> probe attempt with an  -EPROBE_DEFER before reaching the bus/driver
> probe function and hitting this -ENOENT failure. That's why I was
> asking the other questions.

OK. So where is the -EPROBE_DEFER supposed to happen without
driver_deferred_probe_check_state() then?

> > > > On platform_probe() genpd_get_from_provider() returns
> > > > -ENOENT.
> > >
> > > This error is with the series I assume?
> >
> > On the first probe genpd_get_from_provider() will return -ENOENT in
> > both cases. The list is empty on the first probe and there are no
> > genpd providers at this point.
> >
> > Earlier with driver_deferred_probe_check_state(), the initial -ENOENT
> > ends up getting changed to -EPROBE_DEFER at the end of
> > driver_deferred_probe_check_state(), we are now missing that.
> 
> Right, I was aware -ENOENT would be returned if we got this far. But
> the point of this series is that you shouldn't have gotten that far
> before your pm domain device is ready. Hence my questions from the
> earlier reply.

OK

> Can I get answers to rest of my questions in the first reply please?
> That should help us figure out why fw_devlink let us get this far.
> Summarize them here to make it easy:
> * Are you running with fw_devlink=on?

Yes with the default with no specific kernel params so looks like
FW_DEVLINK_FLAGS_ON.

> * Is the"ti,omap4-prm-inst"/"ti,omap-prm-inst" built-in in this case?

Yes

> * If it's not built-in, can you please try deferred_probe_timeout=0
> and deferred_probe_timeout=30 and see if either one of them help?

It's built in so I did not try these.

> * Can I get the output of "ls -d supplier:*" and "cat
> supplier:*/status" output from the sysfs dir for the ocp device
> without this series where it boots properly.

Hmm so I'm not seeing any supplier for the top level ocp device in
the booting case without your patches. I see the suppliers for the
ocp child device instances only.

Without your patches I see simple-pm-bus probe initially with
EPROBE_DEFER like I described earlier, and then simple-pm-bus probes
on the second try.

Regards,

Tony

Saravana Kannan June 23, 2022, 8:21 a.m. UTC | #8

On Thu, Jun 23, 2022 at 12:01 AM Tony Lindgren <[e-mail]> wrote:
>
> * Saravana Kannan <[e-mail]> [220622 19:05]:
> > On Tue, Jun 21, 2022 at 9:59 PM Tony Lindgren <[e-mail]> wrote:
> > >
> > > Hi,
> > >
> > > * Saravana Kannan <[e-mail]> [220621 19:29]:
> > > > On Tue, Jun 21, 2022 at 12:28 AM Tony Lindgren <[e-mail]> wrote:
> > > > >
> > > > > Hi,
> > > > >
> > > > > * Saravana Kannan <[e-mail]> [700101 02:00]:
> > > > > > Now that fw_devlink=on by default and fw_devlink supports
> > > > > > "power-domains" property, the execution will never get to the point
> > > > > > where driver_deferred_probe_check_state() is called before the supplier
> > > > > > has probed successfully or before deferred probe timeout has expired.
> > > > > >
> > > > > > So, delete the call and replace it with -ENODEV.
> > > > >
> > > > > Looks like this causes omaps to not boot in Linux next.
> > > >
> > > > Can you please point me to an example DTS I could use for debugging
> > > > this? I'm assuming you are leaving fw_devlink=on and not turning it
> > > > off or putting it in permissive mode.
> > >
> > > Sure, this seems to happen at least with simple-pm-bus as the top
> > > level interconnect with a configured power-domains property:
> > >
> > > $ git grep -A10 "ocp {" arch/arm/boot/dts/*.dtsi | grep -B3 -A4 simple-pm-bus
> >
> > Thanks for the example. I generally start looking from dts (not dtsi)
> > files in case there are some DT property override/additions after the
> > dtsi files are included in the dts file. But I'll assume for now
> > that's not the case. If there's a specific dts file for a board I can
> > look from that'd be helpful to rule out those kinds of issues.
> >
> > For now, I looked at arch/arm/boot/dts/omap4.dtsi.
>
> OK it should be very similar for all the affected SoCs.
>
> > > This issue is no directly related fw_devlink. It is a side effect of
> > > removing driver_deferred_probe_check_state(). We no longer return
> > > -EPROBE_DEFER at the end of driver_deferred_probe_check_state().
> >
> > Yes, I understand the issue. But driver_deferred_probe_check_state()
> > was deleted because fw_devlink=on should have short circuited the
> > probe attempt with an  -EPROBE_DEFER before reaching the bus/driver
> > probe function and hitting this -ENOENT failure. That's why I was
> > asking the other questions.
>
> OK. So where is the -EPROBE_DEFER supposed to happen without
> driver_deferred_probe_check_state() then?

device_links_check_suppliers() call inside really_probe() would short
circuit and return an -EPROBE_DEFER if the device links are created as
expected.

>
> > > > > On platform_probe() genpd_get_from_provider() returns
> > > > > -ENOENT.
> > > >
> > > > This error is with the series I assume?
> > >
> > > On the first probe genpd_get_from_provider() will return -ENOENT in
> > > both cases. The list is empty on the first probe and there are no
> > > genpd providers at this point.
> > >
> > > Earlier with driver_deferred_probe_check_state(), the initial -ENOENT
> > > ends up getting changed to -EPROBE_DEFER at the end of
> > > driver_deferred_probe_check_state(), we are now missing that.
> >
> > Right, I was aware -ENOENT would be returned if we got this far. But
> > the point of this series is that you shouldn't have gotten that far
> > before your pm domain device is ready. Hence my questions from the
> > earlier reply.
>
> OK
>
> > Can I get answers to rest of my questions in the first reply please?
> > That should help us figure out why fw_devlink let us get this far.
> > Summarize them here to make it easy:
> > * Are you running with fw_devlink=on?
>
> Yes with the default with no specific kernel params so looks like
> FW_DEVLINK_FLAGS_ON.
>
> > * Is the"ti,omap4-prm-inst"/"ti,omap-prm-inst" built-in in this case?
>
> Yes
>
> > * If it's not built-in, can you please try deferred_probe_timeout=0
> > and deferred_probe_timeout=30 and see if either one of them help?
>
> It's built in so I did not try these.
>
> > * Can I get the output of "ls -d supplier:*" and "cat
> > supplier:*/status" output from the sysfs dir for the ocp device
> > without this series where it boots properly.
>
> Hmm so I'm not seeing any supplier for the top level ocp device in
> the booting case without your patches. I see the suppliers for the
> ocp child device instances only.

Hmmm... this is strange (that the device link isn't there), but this
is what I suspected.

Now we need to figure out why it's missing. There are only a few
things that could cause this and I don't see any of those. I already
checked to make sure the power domain in this instance had a proper
driver with a probe() function -- if it didn't, then that's one thing
that'd could have caused the missing device link. The device does seem
to have a proper driver, so looks like I can rule that out.

Can you point me to the dts file that corresponds to the specific
board you are testing this one? I probably won't find anything, but I
want to rule out some of the possibilities.

All the device link creation logic is inside drivers/base/core.c. So
if you can look at the existing messages or add other stuff to figure
out why the device link isn't getting created, that'd be handy. In
either case, I'll continue staring at the DT and code to see what
might be happening here.

-Saravana

Alexander Stein June 23, 2022, 12:08 p.m. UTC | #9

Hi,

Am Dienstag, 21. Juni 2022, 09:28:43 CEST schrieb Tony Lindgren:
> Hi,
> 
> * Saravana Kannan <[e-mail]> [700101 02:00]:
> > Now that fw_devlink=on by default and fw_devlink supports
> > "power-domains" property, the execution will never get to the point
> > where driver_deferred_probe_check_state() is called before the supplier
> > has probed successfully or before deferred probe timeout has expired.
> > 
> > So, delete the call and replace it with -ENODEV.
> 
> Looks like this causes omaps to not boot in Linux next. With this
> simple-pm-bus fails to probe initially as the power-domain is not
> yet available. On platform_probe() genpd_get_from_provider() returns
> -ENOENT.
> 
> Seems like other stuff is potentially broken too, any ideas on
> how to fix this?

I think I'm hit by this as well, although I do not get a lockup.
In my case I'm using arch/arm64/boot/dts/freescale/imx8mq-tqma8mq-mba8mx.dts 
and probing of 38320000.blk-ctrl fails as the power-domain is not (yet) 
registed. See the (filtered) dmesg output:

> [    0.744245] PM: Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@0 [    0.744756] PM:
> Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@2 [    0.745012] PM:
> Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@3 [    0.745268] PM:
> Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@4 [    0.746121] PM:
> Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@7 [    0.746400] PM:
> Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@8 [    0.746665] PM:
> Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@9 [    0.746927] PM:
> Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@a [    0.748870]
> imx8m-blk-ctrl 38320000.blk-ctrl: error -ENODEV: failed to attach bus power
> domain [    1.265279] PM: Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@5 [    1.265861] PM:
> Added domain provider from
> /soc@0/bus@30000000/gpc@303a0000/pgc/power-domain@6

blk-ctrl@38320000 requires the power-domain 'pgc_vpu', which is power-domain@6 
in pgc.

Best regards,
Alexander

> > Signed-off-by: Saravana Kannan <[e-mail]>
> > ---
> > 
> >  drivers/base/power/domain.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> > index 739e52cd4aba..3e86772d5fac 100644
> > --- a/drivers/base/power/domain.c
> > +++ b/drivers/base/power/domain.c
> > @@ -2730,7 +2730,7 @@ static int __genpd_dev_pm_attach(struct device *dev,
> > struct device *base_dev,> 
> >  		mutex_unlock(&gpd_list_lock);
> >  		dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
> >  		
> >  			__func__, PTR_ERR(pd));
> > 
> > -		return driver_deferred_probe_check_state(base_dev);
> > +		return -ENODEV;
> > 
> >  	}
> >  	
> >  	dev_dbg(dev, "adding to PM domain %s\n", pd->name);

Tony Lindgren June 27, 2022, 9:10 a.m. UTC | #10

* Saravana Kannan <[e-mail]> [220623 08:17]:
> On Thu, Jun 23, 2022 at 12:01 AM Tony Lindgren <[e-mail]> wrote:
> >
> > * Saravana Kannan <[e-mail]> [220622 19:05]:
> > > On Tue, Jun 21, 2022 at 9:59 PM Tony Lindgren <[e-mail]> wrote:
> > > > This issue is no directly related fw_devlink. It is a side effect of
> > > > removing driver_deferred_probe_check_state(). We no longer return
> > > > -EPROBE_DEFER at the end of driver_deferred_probe_check_state().
> > >
> > > Yes, I understand the issue. But driver_deferred_probe_check_state()
> > > was deleted because fw_devlink=on should have short circuited the
> > > probe attempt with an  -EPROBE_DEFER before reaching the bus/driver
> > > probe function and hitting this -ENOENT failure. That's why I was
> > > asking the other questions.
> >
> > OK. So where is the -EPROBE_DEFER supposed to happen without
> > driver_deferred_probe_check_state() then?
> 
> device_links_check_suppliers() call inside really_probe() would short
> circuit and return an -EPROBE_DEFER if the device links are created as
> expected.

OK

> > Hmm so I'm not seeing any supplier for the top level ocp device in
> > the booting case without your patches. I see the suppliers for the
> > ocp child device instances only.
> 
> Hmmm... this is strange (that the device link isn't there), but this
> is what I suspected.

Yup, maybe it's because of the supplier being a device in the child
interconnect for the ocp.

> Now we need to figure out why it's missing. There are only a few
> things that could cause this and I don't see any of those. I already
> checked to make sure the power domain in this instance had a proper
> driver with a probe() function -- if it didn't, then that's one thing
> that'd could have caused the missing device link. The device does seem
> to have a proper driver, so looks like I can rule that out.
> 
> Can you point me to the dts file that corresponds to the specific
> board you are testing this one? I probably won't find anything, but I
> want to rule out some of the possibilities.

You can use the beaglebone black dts for example, that's
arch/arm/boot/dts/am335x-boneblack.dts and uses am33xx.dtsi for
ocp interconnect with simple-pm-bus.

> All the device link creation logic is inside drivers/base/core.c. So
> if you can look at the existing messages or add other stuff to figure
> out why the device link isn't getting created, that'd be handy. In
> either case, I'll continue staring at the DT and code to see what
> might be happening here.

In device_links_check_suppliers() I see these ocp suppliers:

platform ocp: device_links_check_suppliers: 1024: supplier 44e00d00.prm: link->status: 0 link->flags: 000001c0
platform ocp: device_links_check_suppliers: 1024: supplier 44e01000.prm: link->status: 0 link->flags: 000001c0
platform ocp: device_links_check_suppliers: 1024: supplier 44e00c00.prm: link->status: 0 link->flags: 000001c0
platform ocp: device_links_check_suppliers: 1024: supplier 44e00e00.prm: link->status: 0 link->flags: 000001c0
platform ocp: device_links_check_suppliers: 1024: supplier 44e01100.prm: link->status: 0 link->flags: 000001c0
platform ocp: device_links_check_suppliers: 1024: supplier fixedregulator0: link->status: 1 link->flags: 000001c0

No -EPROBE_DEFER is returned in device_links_check_suppliers() for
44e00c00.prm supplier for beaglebone black for example, 0 gets
returned.

Regards,

Tony

Saravana Kannan June 30, 2022, 11:10 p.m. UTC | #11

On Mon, Jun 27, 2022 at 2:10 AM Tony Lindgren <[e-mail]> wrote:
>
> * Saravana Kannan <[e-mail]> [220623 08:17]:
> > On Thu, Jun 23, 2022 at 12:01 AM Tony Lindgren <[e-mail]> wrote:
> > >
> > > * Saravana Kannan <[e-mail]> [220622 19:05]:
> > > > On Tue, Jun 21, 2022 at 9:59 PM Tony Lindgren <[e-mail]> wrote:
> > > > > This issue is no directly related fw_devlink. It is a side effect of
> > > > > removing driver_deferred_probe_check_state(). We no longer return
> > > > > -EPROBE_DEFER at the end of driver_deferred_probe_check_state().
> > > >
> > > > Yes, I understand the issue. But driver_deferred_probe_check_state()
> > > > was deleted because fw_devlink=on should have short circuited the
> > > > probe attempt with an  -EPROBE_DEFER before reaching the bus/driver
> > > > probe function and hitting this -ENOENT failure. That's why I was
> > > > asking the other questions.
> > >
> > > OK. So where is the -EPROBE_DEFER supposed to happen without
> > > driver_deferred_probe_check_state() then?
> >
> > device_links_check_suppliers() call inside really_probe() would short
> > circuit and return an -EPROBE_DEFER if the device links are created as
> > expected.
>
> OK
>
> > > Hmm so I'm not seeing any supplier for the top level ocp device in
> > > the booting case without your patches. I see the suppliers for the
> > > ocp child device instances only.
> >
> > Hmmm... this is strange (that the device link isn't there), but this
> > is what I suspected.
>
> Yup, maybe it's because of the supplier being a device in the child
> interconnect for the ocp.

Ugh... yeah, this is why the normal (not SYNC_STATE_ONLY) device link
isn't being created.

So the aggregated view is something like (I had to set tabs = 4 space
to fit it within 80 cols):

    ocp: ocp {         <========================= Consumer
        compatible = "simple-pm-bus";
        power-domains = <&prm_per>; <=========== Supplier ref

                l4_wkup: interconnect@44c00000 {
            compatible = "ti,am33xx-l4-wkup", "simple-pm-bus";

            segment@200000 {  /* 0x44e00000 */
                compatible = "simple-pm-bus";

                target-module@0 { /* 0x44e00000, ap 8 58.0 */
                    compatible = "ti,sysc-omap4", "ti,sysc";

                    prcm: prcm@0 {
                        compatible = "ti,am3-prcm", "simple-bus";

                        prm_per: prm@c00 { <========= Actual Supplier
                            compatible = "ti,am3-prm-inst", "ti,omap-prm-inst";
                        };
                    };
                };
            };
        };
    };

The power-domain supplier is the great-great-great-grand-child of the
consumer. It's not clear to me how this is valid. What does it even
mean?

Rob, is this considered a valid DT?

Geert, thoughts on whether this is a correct use of simple-pm-bus device?

Also, how is the power domain attach/get working in this case? As far
as I can tell, at least for "simple-pm-bus" devices, the pm domain
attachment is happening under:
really_probe() -> call_driver_probe -> platform_probe() ->
dev_pm_domain_attach()

So, how is the pm domain attach succeeding in the first place without
my changes?

> > Now we need to figure out why it's missing. There are only a few
> > things that could cause this and I don't see any of those. I already
> > checked to make sure the power domain in this instance had a proper
> > driver with a probe() function -- if it didn't, then that's one thing
> > that'd could have caused the missing device link. The device does seem
> > to have a proper driver, so looks like I can rule that out.
> >
> > Can you point me to the dts file that corresponds to the specific
> > board you are testing this one? I probably won't find anything, but I
> > want to rule out some of the possibilities.
>
> You can use the beaglebone black dts for example, that's
> arch/arm/boot/dts/am335x-boneblack.dts and uses am33xx.dtsi for
> ocp interconnect with simple-pm-bus.
>
> > All the device link creation logic is inside drivers/base/core.c. So
> > if you can look at the existing messages or add other stuff to figure
> > out why the device link isn't getting created, that'd be handy. In
> > either case, I'll continue staring at the DT and code to see what
> > might be happening here.
>
> In device_links_check_suppliers() I see these ocp suppliers:
>
> platform ocp: device_links_check_suppliers: 1024: supplier 44e00d00.prm: link->status: 0 link->flags: 000001c0
> platform ocp: device_links_check_suppliers: 1024: supplier 44e01000.prm: link->status: 0 link->flags: 000001c0
> platform ocp: device_links_check_suppliers: 1024: supplier 44e00c00.prm: link->status: 0 link->flags: 000001c0
> platform ocp: device_links_check_suppliers: 1024: supplier 44e00e00.prm: link->status: 0 link->flags: 000001c0
> platform ocp: device_links_check_suppliers: 1024: supplier 44e01100.prm: link->status: 0 link->flags: 000001c0
> platform ocp: device_links_check_suppliers: 1024: supplier fixedregulator0: link->status: 1 link->flags: 000001c0
>
> No -EPROBE_DEFER is returned in device_links_check_suppliers() for
> 44e00c00.prm supplier for beaglebone black for example, 0 gets
> returned.

Yeah, the "1c0" flags are SYNC_STATE_ONLY device links and aren't
relevant to the issue we are seeing. Those links are being created as
a proxy for other descendant devices of ocp that haven't been added
yet, but are consumers of these *.prm devices. They are mainly meant
for correctness of sync_state() callbacks of the supplier and don't
affect probe order. For example: target-module@56000000 is a consumer
of prm_gfx 44e01100.prm.

-Saravana

Rob Herring June 30, 2022, 11:26 p.m. UTC | #12

On Thu, Jun 30, 2022 at 5:11 PM Saravana Kannan <[e-mail]> wrote:
>
> On Mon, Jun 27, 2022 at 2:10 AM Tony Lindgren <[e-mail]> wrote:
> >
> > * Saravana Kannan <[e-mail]> [220623 08:17]:
> > > On Thu, Jun 23, 2022 at 12:01 AM Tony Lindgren <[e-mail]> wrote:
> > > >
> > > > * Saravana Kannan <[e-mail]> [220622 19:05]:
> > > > > On Tue, Jun 21, 2022 at 9:59 PM Tony Lindgren <[e-mail]> wrote:
> > > > > > This issue is no directly related fw_devlink. It is a side effect of
> > > > > > removing driver_deferred_probe_check_state(). We no longer return
> > > > > > -EPROBE_DEFER at the end of driver_deferred_probe_check_state().
> > > > >
> > > > > Yes, I understand the issue. But driver_deferred_probe_check_state()
> > > > > was deleted because fw_devlink=on should have short circuited the
> > > > > probe attempt with an  -EPROBE_DEFER before reaching the bus/driver
> > > > > probe function and hitting this -ENOENT failure. That's why I was
> > > > > asking the other questions.
> > > >
> > > > OK. So where is the -EPROBE_DEFER supposed to happen without
> > > > driver_deferred_probe_check_state() then?
> > >
> > > device_links_check_suppliers() call inside really_probe() would short
> > > circuit and return an -EPROBE_DEFER if the device links are created as
> > > expected.
> >
> > OK
> >
> > > > Hmm so I'm not seeing any supplier for the top level ocp device in
> > > > the booting case without your patches. I see the suppliers for the
> > > > ocp child device instances only.
> > >
> > > Hmmm... this is strange (that the device link isn't there), but this
> > > is what I suspected.
> >
> > Yup, maybe it's because of the supplier being a device in the child
> > interconnect for the ocp.
>
> Ugh... yeah, this is why the normal (not SYNC_STATE_ONLY) device link
> isn't being created.
>
> So the aggregated view is something like (I had to set tabs = 4 space
> to fit it within 80 cols):
>
>     ocp: ocp {         <========================= Consumer
>         compatible = "simple-pm-bus";
>         power-domains = <&prm_per>; <=========== Supplier ref
>
>                 l4_wkup: interconnect@44c00000 {
>             compatible = "ti,am33xx-l4-wkup", "simple-pm-bus";
>
>             segment@200000 {  /* 0x44e00000 */
>                 compatible = "simple-pm-bus";
>
>                 target-module@0 { /* 0x44e00000, ap 8 58.0 */
>                     compatible = "ti,sysc-omap4", "ti,sysc";
>
>                     prcm: prcm@0 {
>                         compatible = "ti,am3-prcm", "simple-bus";
>
>                         prm_per: prm@c00 { <========= Actual Supplier
>                             compatible = "ti,am3-prm-inst", "ti,omap-prm-inst";
>                         };
>                     };
>                 };
>             };
>         };
>     };
>
> The power-domain supplier is the great-great-great-grand-child of the
> consumer. It's not clear to me how this is valid. What does it even
> mean?
>
> Rob, is this considered a valid DT?

Valid DT for broken h/w.

So the domain must be default on and then simple-pm-bus is going to
hold a reference to the domain preventing it from ever getting powered
off and things seem to work. Except what happens during suspend?

Rob

Saravana Kannan June 30, 2022, 11:30 p.m. UTC | #13

On Thu, Jun 30, 2022 at 4:26 PM Rob Herring <[e-mail]> wrote:
>
> On Thu, Jun 30, 2022 at 5:11 PM Saravana Kannan <[e-mail]> wrote:
> >
> > On Mon, Jun 27, 2022 at 2:10 AM Tony Lindgren <[e-mail]> wrote:
> > >
> > > * Saravana Kannan <[e-mail]> [220623 08:17]:
> > > > On Thu, Jun 23, 2022 at 12:01 AM Tony Lindgren <[e-mail]> wrote:
> > > > >
> > > > > * Saravana Kannan <[e-mail]> [220622 19:05]:
> > > > > > On Tue, Jun 21, 2022 at 9:59 PM Tony Lindgren <[e-mail]> wrote:
> > > > > > > This issue is no directly related fw_devlink. It is a side effect of
> > > > > > > removing driver_deferred_probe_check_state(). We no longer return
> > > > > > > -EPROBE_DEFER at the end of driver_deferred_probe_check_state().
> > > > > >
> > > > > > Yes, I understand the issue. But driver_deferred_probe_check_state()
> > > > > > was deleted because fw_devlink=on should have short circuited the
> > > > > > probe attempt with an  -EPROBE_DEFER before reaching the bus/driver
> > > > > > probe function and hitting this -ENOENT failure. That's why I was
> > > > > > asking the other questions.
> > > > >
> > > > > OK. So where is the -EPROBE_DEFER supposed to happen without
> > > > > driver_deferred_probe_check_state() then?
> > > >
> > > > device_links_check_suppliers() call inside really_probe() would short
> > > > circuit and return an -EPROBE_DEFER if the device links are created as
> > > > expected.
> > >
> > > OK
> > >
> > > > > Hmm so I'm not seeing any supplier for the top level ocp device in
> > > > > the booting case without your patches. I see the suppliers for the
> > > > > ocp child device instances only.
> > > >
> > > > Hmmm... this is strange (that the device link isn't there), but this
> > > > is what I suspected.
> > >
> > > Yup, maybe it's because of the supplier being a device in the child
> > > interconnect for the ocp.
> >
> > Ugh... yeah, this is why the normal (not SYNC_STATE_ONLY) device link
> > isn't being created.
> >
> > So the aggregated view is something like (I had to set tabs = 4 space
> > to fit it within 80 cols):
> >
> >     ocp: ocp {         <========================= Consumer
> >         compatible = "simple-pm-bus";
> >         power-domains = <&prm_per>; <=========== Supplier ref
> >
> >                 l4_wkup: interconnect@44c00000 {
> >             compatible = "ti,am33xx-l4-wkup", "simple-pm-bus";
> >
> >             segment@200000 {  /* 0x44e00000 */
> >                 compatible = "simple-pm-bus";
> >
> >                 target-module@0 { /* 0x44e00000, ap 8 58.0 */
> >                     compatible = "ti,sysc-omap4", "ti,sysc";
> >
> >                     prcm: prcm@0 {
> >                         compatible = "ti,am3-prcm", "simple-bus";
> >
> >                         prm_per: prm@c00 { <========= Actual Supplier
> >                             compatible = "ti,am3-prm-inst", "ti,omap-prm-inst";
> >                         };
> >                     };
> >                 };
> >             };
> >         };
> >     };
> >
> > The power-domain supplier is the great-great-great-grand-child of the
> > consumer. It's not clear to me how this is valid. What does it even
> > mean?
> >
> > Rob, is this considered a valid DT?
>
> Valid DT for broken h/w.

I'm not sure even in that case it's valid. When the parent device is
in reset (when the SoC is coming out of reset), there's no way the
descendant is functional. And if the descendant is not functional, how
is the parent device powered up? This just feels like an incorrect
representation of the real h/w.

> So the domain must be default on and then simple-pm-bus is going to
> hold a reference to the domain preventing it from ever getting powered
> off and things seem to work. Except what happens during suspend?

But how can simple-pm-bus even get a reference? The PM domain can't
get added until we are well into the probe of the simple-pm-bus and
AFAICT the genpd attach is done before the driver probe is even
called.

-Saravana

Saravana Kannan July 1, 2022, 12:37 a.m. UTC | #14

On Thu, Jun 23, 2022 at 5:08 AM Alexander Stein
<[e-mail]> wrote:
>
> Hi,
>
> Am Dienstag, 21. Juni 2022, 09:28:43 CEST schrieb Tony Lindgren:
> > Hi,
> >
> > * Saravana Kannan <[e-mail]> [700101 02:00]:
> > > Now that fw_devlink=on by default and fw_devlink supports
> > > "power-domains" property, the execution will never get to the point
> > > where driver_deferred_probe_check_state() is called before the supplier
> > > has probed successfully or before deferred probe timeout has expired.
> > >
> > > So, delete the call and replace it with -ENODEV.
> >
> > Looks like this causes omaps to not boot in Linux next. With this
> > simple-pm-bus fails to probe initially as the power-domain is not
> > yet available. On platform_probe() genpd_get_from_provider() returns
> > -ENOENT.
> >
> > Seems like other stuff is potentially broken too, any ideas on
> > how to fix this?
>
> I think I'm hit by this as well, although I do not get a lockup.
> In my case I'm using arch/arm64/boot/dts/freescale/imx8mq-tqma8mq-mba8mx.dts
> and probing of 38320000.blk-ctrl fails as the power-domain is not (yet)
> registed.

Ok, took a look.

The problem is that there are two drivers for the same device and they
both initialize this device.

    gpc: gpc@303a0000 {
        compatible = "fsl,imx8mq-gpc";
    }

$ git grep -l "fsl,imx7d-gpc" -- drivers/
drivers/irqchip/irq-imx-gpcv2.c
drivers/soc/imx/gpcv2.c

IMHO, this is a bad/broken design.

So what's happening is that fw_devlink will block the probe of
38320000.blk-ctrl until 303a0000.gpc is initialized. And it stops
blocking the probe of 38320000.blk-ctrl as soon as the first driver
initializes the device. In this case, it's the irqchip driver.

I'd recommend combining these drivers into one. Something like the
patch I'm attaching (sorry for the attachment, copy-paste is mangling
the tabs). Can you give it a shot please?

-Saravana

Tony Lindgren July 1, 2022, 5:33 a.m. UTC | #15

* Saravana Kannan <[e-mail]> [220630 23:25]:
> On Thu, Jun 30, 2022 at 4:26 PM Rob Herring <[e-mail]> wrote:
> >
> > On Thu, Jun 30, 2022 at 5:11 PM Saravana Kannan <[e-mail]> wrote:
> > >
> > > On Mon, Jun 27, 2022 at 2:10 AM Tony Lindgren <[e-mail]> wrote:
> > > >
> > > > * Saravana Kannan <[e-mail]> [220623 08:17]:
> > > > > On Thu, Jun 23, 2022 at 12:01 AM Tony Lindgren <[e-mail]> wrote:
> > > > > >
> > > > > > * Saravana Kannan <[e-mail]> [220622 19:05]:
> > > > > > > On Tue, Jun 21, 2022 at 9:59 PM Tony Lindgren <[e-mail]> wrote:
> > > > > > > > This issue is no directly related fw_devlink. It is a side effect of
> > > > > > > > removing driver_deferred_probe_check_state(). We no longer return
> > > > > > > > -EPROBE_DEFER at the end of driver_deferred_probe_check_state().
> > > > > > >
> > > > > > > Yes, I understand the issue. But driver_deferred_probe_check_state()
> > > > > > > was deleted because fw_devlink=on should have short circuited the
> > > > > > > probe attempt with an  -EPROBE_DEFER before reaching the bus/driver
> > > > > > > probe function and hitting this -ENOENT failure. That's why I was
> > > > > > > asking the other questions.
> > > > > >
> > > > > > OK. So where is the -EPROBE_DEFER supposed to happen without
> > > > > > driver_deferred_probe_check_state() then?
> > > > >
> > > > > device_links_check_suppliers() call inside really_probe() would short
> > > > > circuit and return an -EPROBE_DEFER if the device links are created as
> > > > > expected.
> > > >
> > > > OK
> > > >
> > > > > > Hmm so I'm not seeing any supplier for the top level ocp device in
> > > > > > the booting case without your patches. I see the suppliers for the
> > > > > > ocp child device instances only.
> > > > >
> > > > > Hmmm... this is strange (that the device link isn't there), but this
> > > > > is what I suspected.
> > > >
> > > > Yup, maybe it's because of the supplier being a device in the child
> > > > interconnect for the ocp.
> > >
> > > Ugh... yeah, this is why the normal (not SYNC_STATE_ONLY) device link
> > > isn't being created.
> > >
> > > So the aggregated view is something like (I had to set tabs = 4 space
> > > to fit it within 80 cols):
> > >
> > >     ocp: ocp {         <========================= Consumer
> > >         compatible = "simple-pm-bus";
> > >         power-domains = <&prm_per>; <=========== Supplier ref
> > >
> > >                 l4_wkup: interconnect@44c00000 {
> > >             compatible = "ti,am33xx-l4-wkup", "simple-pm-bus";
> > >
> > >             segment@200000 {  /* 0x44e00000 */
> > >                 compatible = "simple-pm-bus";
> > >
> > >                 target-module@0 { /* 0x44e00000, ap 8 58.0 */
> > >                     compatible = "ti,sysc-omap4", "ti,sysc";
> > >
> > >                     prcm: prcm@0 {
> > >                         compatible = "ti,am3-prcm", "simple-bus";
> > >
> > >                         prm_per: prm@c00 { <========= Actual Supplier
> > >                             compatible = "ti,am3-prm-inst", "ti,omap-prm-inst";
> > >                         };
> > >                     };
> > >                 };
> > >             };
> > >         };
> > >     };
> > >
> > > The power-domain supplier is the great-great-great-grand-child of the
> > > consumer. It's not clear to me how this is valid. What does it even
> > > mean?
> > >
> > > Rob, is this considered a valid DT?
> >
> > Valid DT for broken h/w.
> 
> I'm not sure even in that case it's valid. When the parent device is
> in reset (when the SoC is coming out of reset), there's no way the
> descendant is functional. And if the descendant is not functional, how
> is the parent device powered up? This just feels like an incorrect
> representation of the real h/w.

It should be correct representation based on scanning the interconnects
and looking at the documentation. Some interconnect parts are wired
always-on and some interconnect instances may be dual-mapped.

We have a quirk to probe prm/prcm first with pdata_quirks_init_clocks().
Maybe that also now fails in addition to the top level interconnect
probing no longer producing -EPROBE_DEFER.

> > So the domain must be default on and then simple-pm-bus is going to
> > hold a reference to the domain preventing it from ever getting powered
> > off and things seem to work. Except what happens during suspend?
> 
> But how can simple-pm-bus even get a reference? The PM domain can't
> get added until we are well into the probe of the simple-pm-bus and
> AFAICT the genpd attach is done before the driver probe is even
> called.

The prm/prcm gets of_platform_populate() called on it early.

Regards,

Tony

Alexander Stein July 1, 2022, 6:01 a.m. UTC | #16

Hi Saravana,

Am Freitag, 1. Juli 2022, 02:37:14 CEST schrieb Saravana Kannan:
> On Thu, Jun 23, 2022 at 5:08 AM Alexander Stein
> 
> <[e-mail]> wrote:
> > Hi,
> > 
> > Am Dienstag, 21. Juni 2022, 09:28:43 CEST schrieb Tony Lindgren:
> > > Hi,
> > > 
> > > * Saravana Kannan <[e-mail]> [700101 02:00]:
> > > > Now that fw_devlink=on by default and fw_devlink supports
> > > > "power-domains" property, the execution will never get to the point
> > > > where driver_deferred_probe_check_state() is called before the
> > > > supplier
> > > > has probed successfully or before deferred probe timeout has expired.
> > > > 
> > > > So, delete the call and replace it with -ENODEV.
> > > 
> > > Looks like this causes omaps to not boot in Linux next. With this
> > > simple-pm-bus fails to probe initially as the power-domain is not
> > > yet available. On platform_probe() genpd_get_from_provider() returns
> > > -ENOENT.
> > > 
> > > Seems like other stuff is potentially broken too, any ideas on
> > > how to fix this?
> > 
> > I think I'm hit by this as well, although I do not get a lockup.
> > In my case I'm using
> > arch/arm64/boot/dts/freescale/imx8mq-tqma8mq-mba8mx.dts and probing of
> > 38320000.blk-ctrl fails as the power-domain is not (yet) registed.
> 
> Ok, took a look.
> 
> The problem is that there are two drivers for the same device and they
> both initialize this device.
> 
>     gpc: gpc@303a0000 {
>         compatible = "fsl,imx8mq-gpc";
>     }
> 
> $ git grep -l "fsl,imx7d-gpc" -- drivers/
> drivers/irqchip/irq-imx-gpcv2.c
> drivers/soc/imx/gpcv2.c
> 
> IMHO, this is a bad/broken design.
> 
> So what's happening is that fw_devlink will block the probe of
> 38320000.blk-ctrl until 303a0000.gpc is initialized. And it stops
> blocking the probe of 38320000.blk-ctrl as soon as the first driver
> initializes the device. In this case, it's the irqchip driver.
> 
> I'd recommend combining these drivers into one. Something like the
> patch I'm attaching (sorry for the attachment, copy-paste is mangling
> the tabs). Can you give it a shot please?

I tried this patch and it delayed the driver initialization (those of UART as 
well BTW). Unfortunately the driver fails the same way:
> [    1.125253] imx8m-blk-ctrl 38320000.blk-ctrl: error -ENODEV: failed to 
attach power domain "bus"

More than that it even introduced some more errors:
> [    0.008160] irq: no irq domain found for gpc@303a0000 !
> [    0.013251] Failed to map interrupt for
> /soc@0/bus@30400000/timer@306a0000
> [    0.020152] Failed to initialize '/soc@0/bus@30400000/timer@306a0000':
> -22

I kept the timestamps to show that these errors happen very early. So now the 
usage of the "global" interrupt parent, set at line 18,
> interrupt-parent = <&gpc>;
is not possible at this point of boot time.

Best regards,
Alexander

Tony Lindgren July 1, 2022, 6:12 a.m. UTC | #17

* Tony Lindgren <[e-mail]> [220701 08:33]:
> * Saravana Kannan <[e-mail]> [220630 23:25]:
> > On Thu, Jun 30, 2022 at 4:26 PM Rob Herring <[e-mail]> wrote:
> > >
> > > On Thu, Jun 30, 2022 at 5:11 PM Saravana Kannan <[e-mail]> wrote:
> > > >
> > > > On Mon, Jun 27, 2022 at 2:10 AM Tony Lindgren <[e-mail]> wrote:
> > > > >
> > > > > * Saravana Kannan <[e-mail]> [220623 08:17]:
> > > > > > On Thu, Jun 23, 2022 at 12:01 AM Tony Lindgren <[e-mail]> wrote:
> > > > > > >
> > > > > > > * Saravana Kannan <[e-mail]> [220622 19:05]:
> > > > > > > > On Tue, Jun 21, 2022 at 9:59 PM Tony Lindgren <[e-mail]> wrote:
> > > > > > > > > This issue is no directly related fw_devlink. It is a side effect of
> > > > > > > > > removing driver_deferred_probe_check_state(). We no longer return
> > > > > > > > > -EPROBE_DEFER at the end of driver_deferred_probe_check_state().
> > > > > > > >
> > > > > > > > Yes, I understand the issue. But driver_deferred_probe_check_state()
> > > > > > > > was deleted because fw_devlink=on should have short circuited the
> > > > > > > > probe attempt with an  -EPROBE_DEFER before reaching the bus/driver
> > > > > > > > probe function and hitting this -ENOENT failure. That's why I was
> > > > > > > > asking the other questions.
> > > > > > >
> > > > > > > OK. So where is the -EPROBE_DEFER supposed to happen without
> > > > > > > driver_deferred_probe_check_state() then?
> > > > > >
> > > > > > device_links_check_suppliers() call inside really_probe() would short
> > > > > > circuit and return an -EPROBE_DEFER if the device links are created as
> > > > > > expected.
> > > > >
> > > > > OK
> > > > >
> > > > > > > Hmm so I'm not seeing any supplier for the top level ocp device in
> > > > > > > the booting case without your patches. I see the suppliers for the
> > > > > > > ocp child device instances only.
> > > > > >
> > > > > > Hmmm... this is strange (that the device link isn't there), but this
> > > > > > is what I suspected.
> > > > >
> > > > > Yup, maybe it's because of the supplier being a device in the child
> > > > > interconnect for the ocp.
> > > >
> > > > Ugh... yeah, this is why the normal (not SYNC_STATE_ONLY) device link
> > > > isn't being created.
> > > >
> > > > So the aggregated view is something like (I had to set tabs = 4 space
> > > > to fit it within 80 cols):
> > > >
> > > >     ocp: ocp {         <========================= Consumer
> > > >         compatible = "simple-pm-bus";
> > > >         power-domains = <&prm_per>; <=========== Supplier ref
> > > >
> > > >                 l4_wkup: interconnect@44c00000 {
> > > >             compatible = "ti,am33xx-l4-wkup", "simple-pm-bus";
> > > >
> > > >             segment@200000 {  /* 0x44e00000 */
> > > >                 compatible = "simple-pm-bus";
> > > >
> > > >                 target-module@0 { /* 0x44e00000, ap 8 58.0 */
> > > >                     compatible = "ti,sysc-omap4", "ti,sysc";
> > > >
> > > >                     prcm: prcm@0 {
> > > >                         compatible = "ti,am3-prcm", "simple-bus";
> > > >
> > > >                         prm_per: prm@c00 { <========= Actual Supplier
> > > >                             compatible = "ti,am3-prm-inst", "ti,omap-prm-inst";
> > > >                         };
> > > >                     };
> > > >                 };
> > > >             };
> > > >         };
> > > >     };
> > > >
> > > > The power-domain supplier is the great-great-great-grand-child of the
> > > > consumer. It's not clear to me how this is valid. What does it even
> > > > mean?
> > > >
> > > > Rob, is this considered a valid DT?
> > >
> > > Valid DT for broken h/w.
> > 
> > I'm not sure even in that case it's valid. When the parent device is
> > in reset (when the SoC is coming out of reset), there's no way the
> > descendant is functional. And if the descendant is not functional, how
> > is the parent device powered up? This just feels like an incorrect
> > representation of the real h/w.
> 
> It should be correct representation based on scanning the interconnects
> and looking at the documentation. Some interconnect parts are wired
> always-on and some interconnect instances may be dual-mapped.
> 
> We have a quirk to probe prm/prcm first with pdata_quirks_init_clocks().
> Maybe that also now fails in addition to the top level interconnect
> probing no longer producing -EPROBE_DEFER.
> 
> > > So the domain must be default on and then simple-pm-bus is going to
> > > hold a reference to the domain preventing it from ever getting powered
> > > off and things seem to work. Except what happens during suspend?
> > 
> > But how can simple-pm-bus even get a reference? The PM domain can't
> > get added until we are well into the probe of the simple-pm-bus and
> > AFAICT the genpd attach is done before the driver probe is even
> > called.
> 
> The prm/prcm gets of_platform_populate() called on it early.

The hackish patch below makes things boot for me, not convinced this
is the preferred fix compared to earlier deferred probe handling though.
Going back to the init level tinkering seems like a step back to me.

Regards,

Tony

8< ----------------
diff --git a/drivers/soc/ti/omap_prm.c b/drivers/soc/ti/omap_prm.c
--- a/drivers/soc/ti/omap_prm.c
+++ b/drivers/soc/ti/omap_prm.c
@@ -991,4 +991,9 @@ static struct platform_driver omap_prm_driver = {
 		.of_match_table	= omap_prm_id_table,
 	},
 };
-builtin_platform_driver(omap_prm_driver);
+
+static int __init omap_prm_init(void)
+{
+        return platform_driver_register(&omap_prm_driver);
+}
+subsys_initcall(omap_prm_init);

Saravana Kannan July 1, 2022, 7:02 a.m. UTC | #18

On Thu, Jun 30, 2022 at 11:02 PM Alexander Stein
<[e-mail]> wrote:
>
> Hi Saravana,
>
> Am Freitag, 1. Juli 2022, 02:37:14 CEST schrieb Saravana Kannan:
> > On Thu, Jun 23, 2022 at 5:08 AM Alexander Stein
> >
> > <[e-mail]> wrote:
> > > Hi,
> > >
> > > Am Dienstag, 21. Juni 2022, 09:28:43 CEST schrieb Tony Lindgren:
> > > > Hi,
> > > >
> > > > * Saravana Kannan <[e-mail]> [700101 02:00]:
> > > > > Now that fw_devlink=on by default and fw_devlink supports
> > > > > "power-domains" property, the execution will never get to the point
> > > > > where driver_deferred_probe_check_state() is called before the
> > > > > supplier
> > > > > has probed successfully or before deferred probe timeout has expired.
> > > > >
> > > > > So, delete the call and replace it with -ENODEV.
> > > >
> > > > Looks like this causes omaps to not boot in Linux next. With this
> > > > simple-pm-bus fails to probe initially as the power-domain is not
> > > > yet available. On platform_probe() genpd_get_from_provider() returns
> > > > -ENOENT.
> > > >
> > > > Seems like other stuff is potentially broken too, any ideas on
> > > > how to fix this?
> > >
> > > I think I'm hit by this as well, although I do not get a lockup.
> > > In my case I'm using
> > > arch/arm64/boot/dts/freescale/imx8mq-tqma8mq-mba8mx.dts and probing of
> > > 38320000.blk-ctrl fails as the power-domain is not (yet) registed.
> >
> > Ok, took a look.
> >
> > The problem is that there are two drivers for the same device and they
> > both initialize this device.
> >
> >     gpc: gpc@303a0000 {
> >         compatible = "fsl,imx8mq-gpc";
> >     }
> >
> > $ git grep -l "fsl,imx7d-gpc" -- drivers/
> > drivers/irqchip/irq-imx-gpcv2.c
> > drivers/soc/imx/gpcv2.c
> >
> > IMHO, this is a bad/broken design.
> >
> > So what's happening is that fw_devlink will block the probe of
> > 38320000.blk-ctrl until 303a0000.gpc is initialized. And it stops
> > blocking the probe of 38320000.blk-ctrl as soon as the first driver
> > initializes the device. In this case, it's the irqchip driver.
> >
> > I'd recommend combining these drivers into one. Something like the
> > patch I'm attaching (sorry for the attachment, copy-paste is mangling
> > the tabs). Can you give it a shot please?
>
> I tried this patch and it delayed the driver initialization (those of UART as
> well BTW). Unfortunately the driver fails the same way:

Thanks for testing the patch!

> > [    1.125253] imx8m-blk-ctrl 38320000.blk-ctrl: error -ENODEV: failed to
> attach power domain "bus"
>
> More than that it even introduced some more errors:
> > [    0.008160] irq: no irq domain found for gpc@303a0000 !

So the idea behind my change was that as long as the irqchip isn't the
root of the irqdomain (might be using the terms incorrectly) like the
gic, you can make it a platform driver. And I was trying to hack up a
patch that's the equivalent of platform_irqchip_probe() (which just
ends up eventually calling the callback you use in IRQCHIP_DECLARE().
I probably made some mistake in the quick hack that I'm sure if
fixable.

> > [    0.013251] Failed to map interrupt for
> > /soc@0/bus@30400000/timer@306a0000

However, this timer driver also uses TIMER_OF_DECLARE() which can't
handle failure to get the IRQ (because it's can't -EPROBE_DEFER). So,
this means, the timer driver inturn needs to be converted to a
platform driver if it's supposed to work with the IRQCHIP_DECLARE()
being converted to a platform driver.

But that's a can of worms not worth opening. But then I remembered
this simpler workaround will work and it is pretty much a variant of
the workaround that's already in the gpc's irqchip driver to allow two
drivers to probe the same device (people really should stop doing
that).

Can you drop my previous hack patch and try this instead please? I'm
99% sure this will work.

diff --git a/drivers/irqchip/irq-imx-gpcv2.c b/drivers/irqchip/irq-imx-gpcv2.c
index b9c22f764b4d..8a0e82067924 100644
--- a/drivers/irqchip/irq-imx-gpcv2.c
+++ b/drivers/irqchip/irq-imx-gpcv2.c
@@ -283,6 +283,7 @@ static int __init imx_gpcv2_irqchip_init(struct
device_node *node,
         * later the GPC power domain driver will not be skipped.
         */
        of_node_clear_flag(node, OF_POPULATED);
+       fwnode_dev_initialized(domain->fwnode, false);
        return 0;
 }

-Saravana

Geert Uytterhoeven July 1, 2022, 7:30 a.m. UTC | #19

Hi Saravana,

On Fri, Jul 1, 2022 at 2:37 AM Saravana Kannan <[e-mail]> wrote:
> On Thu, Jun 23, 2022 at 5:08 AM Alexander Stein
> <[e-mail]> wrote:
> > Am Dienstag, 21. Juni 2022, 09:28:43 CEST schrieb Tony Lindgren:

> > > * Saravana Kannan <[e-mail]> [700101 02:00]:
> > > > Now that fw_devlink=on by default and fw_devlink supports
> > > > "power-domains" property, the execution will never get to the point
> > > > where driver_deferred_probe_check_state() is called before the supplier
> > > > has probed successfully or before deferred probe timeout has expired.
> > > >
> > > > So, delete the call and replace it with -ENODEV.
> > >
> > > Looks like this causes omaps to not boot in Linux next. With this
> > > simple-pm-bus fails to probe initially as the power-domain is not
> > > yet available. On platform_probe() genpd_get_from_provider() returns
> > > -ENOENT.
> > >
> > > Seems like other stuff is potentially broken too, any ideas on
> > > how to fix this?
> >
> > I think I'm hit by this as well, although I do not get a lockup.
> > In my case I'm using arch/arm64/boot/dts/freescale/imx8mq-tqma8mq-mba8mx.dts
> > and probing of 38320000.blk-ctrl fails as the power-domain is not (yet)
> > registed.
>
> Ok, took a look.
>
> The problem is that there are two drivers for the same device and they
> both initialize this device.
>
>     gpc: gpc@303a0000 {
>         compatible = "fsl,imx8mq-gpc";
>     }
>
> $ git grep -l "fsl,imx7d-gpc" -- drivers/
> drivers/irqchip/irq-imx-gpcv2.c
> drivers/soc/imx/gpcv2.c

You missed the "driver" in arch/arm/mach-imx/src.c ;-)

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [e-mail]

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Geert Uytterhoeven July 1, 2022, 7:38 a.m. UTC | #20

Hi Saravana,

On Fri, Jul 1, 2022 at 1:11 AM Saravana Kannan <[e-mail]> wrote:
> On Mon, Jun 27, 2022 at 2:10 AM Tony Lindgren <[e-mail]> wrote:
> > * Saravana Kannan <[e-mail]> [220623 08:17]:
> > > On Thu, Jun 23, 2022 at 12:01 AM Tony Lindgren <[e-mail]> wrote:
> > > > * Saravana Kannan <[e-mail]> [220622 19:05]:
> > > > > On Tue, Jun 21, 2022 at 9:59 PM Tony Lindgren <[e-mail]> wrote:
> > > > > > This issue is no directly related fw_devlink. It is a side effect of
> > > > > > removing driver_deferred_probe_check_state(). We no longer return
> > > > > > -EPROBE_DEFER at the end of driver_deferred_probe_check_state().
> > > > >
> > > > > Yes, I understand the issue. But driver_deferred_probe_check_state()
> > > > > was deleted because fw_devlink=on should have short circuited the
> > > > > probe attempt with an  -EPROBE_DEFER before reaching the bus/driver
> > > > > probe function and hitting this -ENOENT failure. That's why I was
> > > > > asking the other questions.
> > > >
> > > > OK. So where is the -EPROBE_DEFER supposed to happen without
> > > > driver_deferred_probe_check_state() then?
> > >
> > > device_links_check_suppliers() call inside really_probe() would short
> > > circuit and return an -EPROBE_DEFER if the device links are created as
> > > expected.
> >
> > OK
> >
> > > > Hmm so I'm not seeing any supplier for the top level ocp device in
> > > > the booting case without your patches. I see the suppliers for the
> > > > ocp child device instances only.
> > >
> > > Hmmm... this is strange (that the device link isn't there), but this
> > > is what I suspected.
> >
> > Yup, maybe it's because of the supplier being a device in the child
> > interconnect for the ocp.
>
> Ugh... yeah, this is why the normal (not SYNC_STATE_ONLY) device link
> isn't being created.
>
> So the aggregated view is something like (I had to set tabs = 4 space
> to fit it within 80 cols):
>
>     ocp: ocp {         <========================= Consumer
>         compatible = "simple-pm-bus";
>         power-domains = <&prm_per>; <=========== Supplier ref
>
>                 l4_wkup: interconnect@44c00000 {
>             compatible = "ti,am33xx-l4-wkup", "simple-pm-bus";
>
>             segment@200000 {  /* 0x44e00000 */
>                 compatible = "simple-pm-bus";
>
>                 target-module@0 { /* 0x44e00000, ap 8 58.0 */
>                     compatible = "ti,sysc-omap4", "ti,sysc";
>
>                     prcm: prcm@0 {
>                         compatible = "ti,am3-prcm", "simple-bus";
>
>                         prm_per: prm@c00 { <========= Actual Supplier
>                             compatible = "ti,am3-prm-inst", "ti,omap-prm-inst";
>                         };
>                     };
>                 };
>             };
>         };
>     };
>
> The power-domain supplier is the great-great-great-grand-child of the
> consumer. It's not clear to me how this is valid. What does it even
> mean?
>
> Rob, is this considered a valid DT?
>
> Geert, thoughts on whether this is a correct use of simple-pm-bus device?

Well, if the hardware is wired that way...

It's not that dissimilar from CPU cores, and interrupt and GPIO
controllers in power domains and clocked by controllable clocks:
you can cut the branch you're sitting on, and you have to be careful
when going to sleep, and make sure your wake-up sources are still
functional.

> Also, how is the power domain attach/get working in this case? As far
> as I can tell, at least for "simple-pm-bus" devices, the pm domain
> attachment is happening under:
> really_probe() -> call_driver_probe -> platform_probe() ->
> dev_pm_domain_attach()
>
> So, how is the pm domain attach succeeding in the first place without
> my changes?

That's a software thing ;-)

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [e-mail]

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Saravana Kannan July 1, 2022, 8:10 a.m. UTC | #21

On Thu, Jun 30, 2022 at 11:12 PM Tony Lindgren <[e-mail]> wrote:
>
> * Tony Lindgren <[e-mail]> [220701 08:33]:
> > * Saravana Kannan <[e-mail]> [220630 23:25]:
> > > On Thu, Jun 30, 2022 at 4:26 PM Rob Herring <[e-mail]> wrote:
> > > >
> > > > On Thu, Jun 30, 2022 at 5:11 PM Saravana Kannan <[e-mail]> wrote:
> > > > >
> > > > > On Mon, Jun 27, 2022 at 2:10 AM Tony Lindgren <[e-mail]> wrote:
> > > > > >
> > > > > > * Saravana Kannan <[e-mail]> [220623 08:17]:
> > > > > > > On Thu, Jun 23, 2022 at 12:01 AM Tony Lindgren <[e-mail]> wrote:
> > > > > > > >
> > > > > > > > * Saravana Kannan <[e-mail]> [220622 19:05]:
> > > > > > > > > On Tue, Jun 21, 2022 at 9:59 PM Tony Lindgren <[e-mail]> wrote:
> > > > > > > > > > This issue is no directly related fw_devlink. It is a side effect of
> > > > > > > > > > removing driver_deferred_probe_check_state(). We no longer return
> > > > > > > > > > -EPROBE_DEFER at the end of driver_deferred_probe_check_state().
> > > > > > > > >
> > > > > > > > > Yes, I understand the issue. But driver_deferred_probe_check_state()
> > > > > > > > > was deleted because fw_devlink=on should have short circuited the
> > > > > > > > > probe attempt with an  -EPROBE_DEFER before reaching the bus/driver
> > > > > > > > > probe function and hitting this -ENOENT failure. That's why I was
> > > > > > > > > asking the other questions.
> > > > > > > >
> > > > > > > > OK. So where is the -EPROBE_DEFER supposed to happen without
> > > > > > > > driver_deferred_probe_check_state() then?
> > > > > > >
> > > > > > > device_links_check_suppliers() call inside really_probe() would short
> > > > > > > circuit and return an -EPROBE_DEFER if the device links are created as
> > > > > > > expected.
> > > > > >
> > > > > > OK
> > > > > >
> > > > > > > > Hmm so I'm not seeing any supplier for the top level ocp device in
> > > > > > > > the booting case without your patches. I see the suppliers for the
> > > > > > > > ocp child device instances only.
> > > > > > >
> > > > > > > Hmmm... this is strange (that the device link isn't there), but this
> > > > > > > is what I suspected.
> > > > > >
> > > > > > Yup, maybe it's because of the supplier being a device in the child
> > > > > > interconnect for the ocp.
> > > > >
> > > > > Ugh... yeah, this is why the normal (not SYNC_STATE_ONLY) device link
> > > > > isn't being created.
> > > > >
> > > > > So the aggregated view is something like (I had to set tabs = 4 space
> > > > > to fit it within 80 cols):
> > > > >
> > > > >     ocp: ocp {         <========================= Consumer
> > > > >         compatible = "simple-pm-bus";
> > > > >         power-domains = <&prm_per>; <=========== Supplier ref
> > > > >
> > > > >                 l4_wkup: interconnect@44c00000 {
> > > > >             compatible = "ti,am33xx-l4-wkup", "simple-pm-bus";
> > > > >
> > > > >             segment@200000 {  /* 0x44e00000 */
> > > > >                 compatible = "simple-pm-bus";
> > > > >
> > > > >                 target-module@0 { /* 0x44e00000, ap 8 58.0 */
> > > > >                     compatible = "ti,sysc-omap4", "ti,sysc";
> > > > >
> > > > >                     prcm: prcm@0 {
> > > > >                         compatible = "ti,am3-prcm", "simple-bus";
> > > > >
> > > > >                         prm_per: prm@c00 { <========= Actual Supplier
> > > > >                             compatible = "ti,am3-prm-inst", "ti,omap-prm-inst";
> > > > >                         };
> > > > >                     };
> > > > >                 };
> > > > >             };
> > > > >         };
> > > > >     };
> > > > >
> > > > > The power-domain supplier is the great-great-great-grand-child of the
> > > > > consumer. It's not clear to me how this is valid. What does it even
> > > > > mean?
> > > > >
> > > > > Rob, is this considered a valid DT?
> > > >
> > > > Valid DT for broken h/w.
> > >
> > > I'm not sure even in that case it's valid. When the parent device is
> > > in reset (when the SoC is coming out of reset), there's no way the
> > > descendant is functional. And if the descendant is not functional, how
> > > is the parent device powered up? This just feels like an incorrect
> > > representation of the real h/w.
> >
> > It should be correct representation based on scanning the interconnects
> > and looking at the documentation. Some interconnect parts are wired
> > always-on and some interconnect instances may be dual-mapped.

Thanks for helping to debug this. Appreciate it.

> >
> > We have a quirk to probe prm/prcm first with pdata_quirks_init_clocks().

:'(

I checked out the code. These prm devices just get populated with NULL
as the parent. So they are effectively top level devices from the
perspective of driver core.

> > Maybe that also now fails in addition to the top level interconnect
> > probing no longer producing -EPROBE_DEFER.

As far as I can tell pdata_quirks_init_clocks() is just adding these
prm devices (amongst other drivers). So I don't expect that to fail.

> >
> > > > So the domain must be default on and then simple-pm-bus is going to
> > > > hold a reference to the domain preventing it from ever getting powered
> > > > off and things seem to work. Except what happens during suspend?
> > >
> > > But how can simple-pm-bus even get a reference? The PM domain can't
> > > get added until we are well into the probe of the simple-pm-bus and
> > > AFAICT the genpd attach is done before the driver probe is even
> > > called.
> >
> > The prm/prcm gets of_platform_populate() called on it early.

:'(

> The hackish patch below makes things boot for me, not convinced this
> is the preferred fix compared to earlier deferred probe handling though.
> Going back to the init level tinkering seems like a step back to me.

The goal of fw_devlink is to avoid init level tinkering and it does
help with that in general. But these kinds of quirks are going to need
a few exceptions -- with them being quirks and all. And this change
will avoid an unnecessary deferred probe (that used to happen even
before my change).

The other option to handle this quirk is to create the invalid
(consumer is parent of supplier) fwnode_link between the prm device
and its consumers when the prm device is populated. Then fw_devlink
will end up creating a device link when ocp gets added. But I'm not
sure if it's going to be easy to find and add all those consumers.

I'd say, for now, let's go with this patch below. I'll see if I can
get fw_devlink to handle these odd quirks without breaking the normal
cases or making them significantly slower. But that'll take some time
and I'm not sure there'll be a nice solution.

Thanks,
Saravana

> Regards,
>
> Tony
>
> 8< ----------------
> diff --git a/drivers/soc/ti/omap_prm.c b/drivers/soc/ti/omap_prm.c
> --- a/drivers/soc/ti/omap_prm.c
> +++ b/drivers/soc/ti/omap_prm.c
> @@ -991,4 +991,9 @@ static struct platform_driver omap_prm_driver = {
>                 .of_match_table = omap_prm_id_table,
>         },
>  };
> -builtin_platform_driver(omap_prm_driver);
> +
> +static int __init omap_prm_init(void)
> +{
> +        return platform_driver_register(&omap_prm_driver);
> +}
> +subsys_initcall(omap_prm_init);
> --
> 2.36.1
>
> --
> To unsubscribe from this group and stop receiving emails from it, send an email to [e-mail].
>

Saravana Kannan July 1, 2022, 8:26 a.m. UTC | #22

On Fri, Jul 1, 2022 at 1:10 AM Saravana Kannan <[e-mail]> wrote:
>
> On Thu, Jun 30, 2022 at 11:12 PM Tony Lindgren <[e-mail]> wrote:
> >
> > * Tony Lindgren <[e-mail]> [220701 08:33]:
> > > * Saravana Kannan <[e-mail]> [220630 23:25]:
> > > > On Thu, Jun 30, 2022 at 4:26 PM Rob Herring <[e-mail]> wrote:
> > > > >
> > > > > On Thu, Jun 30, 2022 at 5:11 PM Saravana Kannan <[e-mail]> wrote:
> > > > > >
> > > > > > On Mon, Jun 27, 2022 at 2:10 AM Tony Lindgren <[e-mail]> wrote:
> > > > > > >
> > > > > > > * Saravana Kannan <[e-mail]> [220623 08:17]:
> > > > > > > > On Thu, Jun 23, 2022 at 12:01 AM Tony Lindgren <[e-mail]> wrote:
> > > > > > > > >
> > > > > > > > > * Saravana Kannan <[e-mail]> [220622 19:05]:
> > > > > > > > > > On Tue, Jun 21, 2022 at 9:59 PM Tony Lindgren <[e-mail]> wrote:
> > > > > > > > > > > This issue is no directly related fw_devlink. It is a side effect of
> > > > > > > > > > > removing driver_deferred_probe_check_state(). We no longer return
> > > > > > > > > > > -EPROBE_DEFER at the end of driver_deferred_probe_check_state().
> > > > > > > > > >
> > > > > > > > > > Yes, I understand the issue. But driver_deferred_probe_check_state()
> > > > > > > > > > was deleted because fw_devlink=on should have short circuited the
> > > > > > > > > > probe attempt with an  -EPROBE_DEFER before reaching the bus/driver
> > > > > > > > > > probe function and hitting this -ENOENT failure. That's why I was
> > > > > > > > > > asking the other questions.
> > > > > > > > >
> > > > > > > > > OK. So where is the -EPROBE_DEFER supposed to happen without
> > > > > > > > > driver_deferred_probe_check_state() then?
> > > > > > > >
> > > > > > > > device_links_check_suppliers() call inside really_probe() would short
> > > > > > > > circuit and return an -EPROBE_DEFER if the device links are created as
> > > > > > > > expected.
> > > > > > >
> > > > > > > OK
> > > > > > >
> > > > > > > > > Hmm so I'm not seeing any supplier for the top level ocp device in
> > > > > > > > > the booting case without your patches. I see the suppliers for the
> > > > > > > > > ocp child device instances only.
> > > > > > > >
> > > > > > > > Hmmm... this is strange (that the device link isn't there), but this
> > > > > > > > is what I suspected.
> > > > > > >
> > > > > > > Yup, maybe it's because of the supplier being a device in the child
> > > > > > > interconnect for the ocp.
> > > > > >
> > > > > > Ugh... yeah, this is why the normal (not SYNC_STATE_ONLY) device link
> > > > > > isn't being created.
> > > > > >
> > > > > > So the aggregated view is something like (I had to set tabs = 4 space
> > > > > > to fit it within 80 cols):
> > > > > >
> > > > > >     ocp: ocp {         <========================= Consumer
> > > > > >         compatible = "simple-pm-bus";
> > > > > >         power-domains = <&prm_per>; <=========== Supplier ref
> > > > > >
> > > > > >                 l4_wkup: interconnect@44c00000 {
> > > > > >             compatible = "ti,am33xx-l4-wkup", "simple-pm-bus";
> > > > > >
> > > > > >             segment@200000 {  /* 0x44e00000 */
> > > > > >                 compatible = "simple-pm-bus";
> > > > > >
> > > > > >                 target-module@0 { /* 0x44e00000, ap 8 58.0 */
> > > > > >                     compatible = "ti,sysc-omap4", "ti,sysc";
> > > > > >
> > > > > >                     prcm: prcm@0 {
> > > > > >                         compatible = "ti,am3-prcm", "simple-bus";
> > > > > >
> > > > > >                         prm_per: prm@c00 { <========= Actual Supplier
> > > > > >                             compatible = "ti,am3-prm-inst", "ti,omap-prm-inst";
> > > > > >                         };
> > > > > >                     };
> > > > > >                 };
> > > > > >             };
> > > > > >         };
> > > > > >     };
> > > > > >
> > > > > > The power-domain supplier is the great-great-great-grand-child of the
> > > > > > consumer. It's not clear to me how this is valid. What does it even
> > > > > > mean?
> > > > > >
> > > > > > Rob, is this considered a valid DT?
> > > > >
> > > > > Valid DT for broken h/w.
> > > >
> > > > I'm not sure even in that case it's valid. When the parent device is
> > > > in reset (when the SoC is coming out of reset), there's no way the
> > > > descendant is functional. And if the descendant is not functional, how
> > > > is the parent device powered up? This just feels like an incorrect
> > > > representation of the real h/w.
> > >
> > > It should be correct representation based on scanning the interconnects
> > > and looking at the documentation. Some interconnect parts are wired
> > > always-on and some interconnect instances may be dual-mapped.
>
> Thanks for helping to debug this. Appreciate it.
>
> > >
> > > We have a quirk to probe prm/prcm first with pdata_quirks_init_clocks().
>
> :'(
>
> I checked out the code. These prm devices just get populated with NULL
> as the parent. So they are effectively top level devices from the
> perspective of driver core.
>
> > > Maybe that also now fails in addition to the top level interconnect
> > > probing no longer producing -EPROBE_DEFER.
>
> As far as I can tell pdata_quirks_init_clocks() is just adding these
> prm devices (amongst other drivers). So I don't expect that to fail.
>
> > >
> > > > > So the domain must be default on and then simple-pm-bus is going to
> > > > > hold a reference to the domain preventing it from ever getting powered
> > > > > off and things seem to work. Except what happens during suspend?
> > > >
> > > > But how can simple-pm-bus even get a reference? The PM domain can't
> > > > get added until we are well into the probe of the simple-pm-bus and
> > > > AFAICT the genpd attach is done before the driver probe is even
> > > > called.
> > >
> > > The prm/prcm gets of_platform_populate() called on it early.
>
> :'(
>
> > The hackish patch below makes things boot for me, not convinced this
> > is the preferred fix compared to earlier deferred probe handling though.
> > Going back to the init level tinkering seems like a step back to me.
>
> The goal of fw_devlink is to avoid init level tinkering and it does
> help with that in general. But these kinds of quirks are going to need
> a few exceptions -- with them being quirks and all. And this change
> will avoid an unnecessary deferred probe (that used to happen even
> before my change).
>
> The other option to handle this quirk is to create the invalid
> (consumer is parent of supplier) fwnode_link between the prm device
> and its consumers when the prm device is populated. Then fw_devlink
> will end up creating a device link when ocp gets added. But I'm not
> sure if it's going to be easy to find and add all those consumers.
>
> I'd say, for now, let's go with this patch below. I'll see if I can
> get fw_devlink to handle these odd quirks without breaking the normal
> cases or making them significantly slower. But that'll take some time
> and I'm not sure there'll be a nice solution.

Can you check if this hack helps? If so, then I can think about
whether we can pick it up without breaking everything else. Copy-paste
tab mess up warning.

-Saravana

8< ----------------

diff --git a/drivers/of/property.c b/drivers/of/property.c
index 967f79b59016..f671a7528719 100644
--- a/drivers/of/property.c
+++ b/drivers/of/property.c
@@ -1138,18 +1138,6 @@ static int of_link_to_phandle(struct device_node *con_np,
                return -ENODEV;
        }

-       /*
-        * Don't allow linking a device node as a consumer of one of its
-        * descendant nodes. By definition, a child node can't be a functional
-        * dependency for the parent node.
-        */
-       if (of_is_ancestor_of(con_np, sup_np)) {
-               pr_debug("Not linking %pOFP to %pOFP - is descendant\n",
-                        con_np, sup_np);
-               of_node_put(sup_np);
-               return -EINVAL;
-       }
-
        /*
         * Don't create links to "early devices" that won't have struct devices
         * created for them.
@@ -1163,6 +1151,25 @@ static int of_link_to_phandle(struct device_node *con_np,
                of_node_put(sup_np);
                return -ENODEV;
        }
+
+       /*
+        * Don't allow linking a device node as a consumer of one of its
+        * descendant nodes. By definition, a child node can't be a functional
+        * dependency for the parent node.
+        *
+        * However, if the child node already has a device while the parent is
+        * in the process of being added, it's probably some weird quirk
+        * handling. So, don't both checking if the consumer is an ancestor of
+        * the supplier.
+        */
+       if (!sup_dev && of_is_ancestor_of(con_np, sup_np)) {
+               pr_debug("Not linking %pOFP to %pOFP - is descendant\n",
+                        con_np, sup_np);
+               put_device(sup_dev);
+               of_node_put(sup_np);
+               return -EINVAL;
+       }
+

Tony Lindgren July 1, 2022, 1 p.m. UTC | #23

* Saravana Kannan <[e-mail]> [220701 08:21]:
> On Fri, Jul 1, 2022 at 1:10 AM Saravana Kannan <[e-mail]> wrote:
> >
> > On Thu, Jun 30, 2022 at 11:12 PM Tony Lindgren <[e-mail]> wrote:
> > >
> > > * Tony Lindgren <[e-mail]> [220701 08:33]:
> > > > * Saravana Kannan <[e-mail]> [220630 23:25]:
> > > > > On Thu, Jun 30, 2022 at 4:26 PM Rob Herring <[e-mail]> wrote:
> > > > > >
> > > > > > On Thu, Jun 30, 2022 at 5:11 PM Saravana Kannan <[e-mail]> wrote:
> > > > > > >
> > > > > > > On Mon, Jun 27, 2022 at 2:10 AM Tony Lindgren <[e-mail]> wrote:
> > > > > > > >
> > > > > > > > * Saravana Kannan <[e-mail]> [220623 08:17]:
> > > > > > > > > On Thu, Jun 23, 2022 at 12:01 AM Tony Lindgren <[e-mail]> wrote:
> > > > > > > > > >
> > > > > > > > > > * Saravana Kannan <[e-mail]> [220622 19:05]:
> > > > > > > > > > > On Tue, Jun 21, 2022 at 9:59 PM Tony Lindgren <[e-mail]> wrote:
> > > > > > > > > > > > This issue is no directly related fw_devlink. It is a side effect of
> > > > > > > > > > > > removing driver_deferred_probe_check_state(). We no longer return
> > > > > > > > > > > > -EPROBE_DEFER at the end of driver_deferred_probe_check_state().
> > > > > > > > > > >
> > > > > > > > > > > Yes, I understand the issue. But driver_deferred_probe_check_state()
> > > > > > > > > > > was deleted because fw_devlink=on should have short circuited the
> > > > > > > > > > > probe attempt with an  -EPROBE_DEFER before reaching the bus/driver
> > > > > > > > > > > probe function and hitting this -ENOENT failure. That's why I was
> > > > > > > > > > > asking the other questions.
> > > > > > > > > >
> > > > > > > > > > OK. So where is the -EPROBE_DEFER supposed to happen without
> > > > > > > > > > driver_deferred_probe_check_state() then?
> > > > > > > > >
> > > > > > > > > device_links_check_suppliers() call inside really_probe() would short
> > > > > > > > > circuit and return an -EPROBE_DEFER if the device links are created as
> > > > > > > > > expected.
> > > > > > > >
> > > > > > > > OK
> > > > > > > >
> > > > > > > > > > Hmm so I'm not seeing any supplier for the top level ocp device in
> > > > > > > > > > the booting case without your patches. I see the suppliers for the
> > > > > > > > > > ocp child device instances only.
> > > > > > > > >
> > > > > > > > > Hmmm... this is strange (that the device link isn't there), but this
> > > > > > > > > is what I suspected.
> > > > > > > >
> > > > > > > > Yup, maybe it's because of the supplier being a device in the child
> > > > > > > > interconnect for the ocp.
> > > > > > >
> > > > > > > Ugh... yeah, this is why the normal (not SYNC_STATE_ONLY) device link
> > > > > > > isn't being created.
> > > > > > >
> > > > > > > So the aggregated view is something like (I had to set tabs = 4 space
> > > > > > > to fit it within 80 cols):
> > > > > > >
> > > > > > >     ocp: ocp {         <========================= Consumer
> > > > > > >         compatible = "simple-pm-bus";
> > > > > > >         power-domains = <&prm_per>; <=========== Supplier ref
> > > > > > >
> > > > > > >                 l4_wkup: interconnect@44c00000 {
> > > > > > >             compatible = "ti,am33xx-l4-wkup", "simple-pm-bus";
> > > > > > >
> > > > > > >             segment@200000 {  /* 0x44e00000 */
> > > > > > >                 compatible = "simple-pm-bus";
> > > > > > >
> > > > > > >                 target-module@0 { /* 0x44e00000, ap 8 58.0 */
> > > > > > >                     compatible = "ti,sysc-omap4", "ti,sysc";
> > > > > > >
> > > > > > >                     prcm: prcm@0 {
> > > > > > >                         compatible = "ti,am3-prcm", "simple-bus";
> > > > > > >
> > > > > > >                         prm_per: prm@c00 { <========= Actual Supplier
> > > > > > >                             compatible = "ti,am3-prm-inst", "ti,omap-prm-inst";
> > > > > > >                         };
> > > > > > >                     };
> > > > > > >                 };
> > > > > > >             };
> > > > > > >         };
> > > > > > >     };
> > > > > > >
> > > > > > > The power-domain supplier is the great-great-great-grand-child of the
> > > > > > > consumer. It's not clear to me how this is valid. What does it even
> > > > > > > mean?
> > > > > > >
> > > > > > > Rob, is this considered a valid DT?
> > > > > >
> > > > > > Valid DT for broken h/w.
> > > > >
> > > > > I'm not sure even in that case it's valid. When the parent device is
> > > > > in reset (when the SoC is coming out of reset), there's no way the
> > > > > descendant is functional. And if the descendant is not functional, how
> > > > > is the parent device powered up? This just feels like an incorrect
> > > > > representation of the real h/w.
> > > >
> > > > It should be correct representation based on scanning the interconnects
> > > > and looking at the documentation. Some interconnect parts are wired
> > > > always-on and some interconnect instances may be dual-mapped.
> >
> > Thanks for helping to debug this. Appreciate it.
> >
> > > >
> > > > We have a quirk to probe prm/prcm first with pdata_quirks_init_clocks().
> >
> > :'(
> >
> > I checked out the code. These prm devices just get populated with NULL
> > as the parent. So they are effectively top level devices from the
> > perspective of driver core.
> >
> > > > Maybe that also now fails in addition to the top level interconnect
> > > > probing no longer producing -EPROBE_DEFER.
> >
> > As far as I can tell pdata_quirks_init_clocks() is just adding these
> > prm devices (amongst other drivers). So I don't expect that to fail.
> >
> > > >
> > > > > > So the domain must be default on and then simple-pm-bus is going to
> > > > > > hold a reference to the domain preventing it from ever getting powered
> > > > > > off and things seem to work. Except what happens during suspend?
> > > > >
> > > > > But how can simple-pm-bus even get a reference? The PM domain can't
> > > > > get added until we are well into the probe of the simple-pm-bus and
> > > > > AFAICT the genpd attach is done before the driver probe is even
> > > > > called.
> > > >
> > > > The prm/prcm gets of_platform_populate() called on it early.
> >
> > :'(
> >
> > > The hackish patch below makes things boot for me, not convinced this
> > > is the preferred fix compared to earlier deferred probe handling though.
> > > Going back to the init level tinkering seems like a step back to me.
> >
> > The goal of fw_devlink is to avoid init level tinkering and it does
> > help with that in general. But these kinds of quirks are going to need
> > a few exceptions -- with them being quirks and all. And this change
> > will avoid an unnecessary deferred probe (that used to happen even
> > before my change).
> >
> > The other option to handle this quirk is to create the invalid
> > (consumer is parent of supplier) fwnode_link between the prm device
> > and its consumers when the prm device is populated. Then fw_devlink
> > will end up creating a device link when ocp gets added. But I'm not
> > sure if it's going to be easy to find and add all those consumers.
> >
> > I'd say, for now, let's go with this patch below. I'll see if I can
> > get fw_devlink to handle these odd quirks without breaking the normal
> > cases or making them significantly slower. But that'll take some time
> > and I'm not sure there'll be a nice solution.
> 
> Can you check if this hack helps? If so, then I can think about
> whether we can pick it up without breaking everything else. Copy-paste
> tab mess up warning.

Yeah so manually applying your patch while updating it against
next-20220624 kernel boots for me. I ended up with the following
changes FYI.

Also, looks like both with the initcall change for prm, and the patch
below, there seems to be also another problem where my test devices no
longer properly idle somehow compared to reverting the your two patches
in next.

Regards,

Tony

8< -------------------
diff --git a/drivers/of/property.c b/drivers/of/property.c
--- a/drivers/of/property.c
+++ b/drivers/of/property.c
@@ -1138,18 +1138,6 @@ static int of_link_to_phandle(struct device_node *con_np,
 		return -ENODEV;
 	}
 
-	/*
-	 * Don't allow linking a device node as a consumer of one of its
-	 * descendant nodes. By definition, a child node can't be a functional
-	 * dependency for the parent node.
-	 */
-	if (of_is_ancestor_of(con_np, sup_np)) {
-		pr_debug("Not linking %pOFP to %pOFP - is descendant\n",
-			 con_np, sup_np);
-		of_node_put(sup_np);
-		return -EINVAL;
-	}
-
 	/*
 	 * Don't create links to "early devices" that won't have struct devices
 	 * created for them.
@@ -1163,9 +1151,27 @@ static int of_link_to_phandle(struct device_node *con_np,
 		of_node_put(sup_np);
 		return -ENODEV;
 	}
-	put_device(sup_dev);
+
+	/*
+	 * Don't allow linking a device node as a consumer of one of its
+	 * descendant nodes. By definition, a child node can't be a functional
+	 * dependency for the parent node.
+	 *
+	 * However, if the child node already has a device while the parent is
+	 * in the process of being added, it's probably some weird quirk
+	 * handling. So, don't both checking if the consumer is an ancestor of
+	 * the supplier.
+	 */
+	if (!sup_dev && of_is_ancestor_of(con_np, sup_np)) {
+		pr_debug("Not linking %pOFP to %pOFP - is descendant\n",
+			 con_np, sup_np);
+		put_device(sup_dev);
+		of_node_put(sup_np);
+		return -EINVAL;
+	}
 
 	fwnode_link_add(of_fwnode_handle(con_np), of_fwnode_handle(sup_np));
+	put_device(sup_dev);
 	of_node_put(sup_np);
 
 	return 0;

Sudeep Holla July 1, 2022, 3:08 p.m. UTC | #24

Hi, Saravana,

On Fri, Jul 01, 2022 at 01:26:12AM -0700, Saravana Kannan wrote:

[...]

> Can you check if this hack helps? If so, then I can think about
> whether we can pick it up without breaking everything else. Copy-paste
> tab mess up warning.

Sorry for jumping in late and not even sure if this is right thread.
I have not bisected anything yet, but I am seeing issues on my Juno R2
with SCMI enabled power domains and Coresight AMBA devices.

OF: amba_device_add() failed (-19) for /etf@20010000
OF: amba_device_add() failed (-19) for /tpiu@20030000
OF: amba_device_add() failed (-19) for /funnel@20040000
OF: amba_device_add() failed (-19) for /etr@20070000
OF: amba_device_add() failed (-19) for /stm@20100000
OF: amba_device_add() failed (-19) for /replicator@20120000
OF: amba_device_add() failed (-19) for /cpu-debug@22010000
OF: amba_device_add() failed (-19) for /etm@22040000
OF: amba_device_add() failed (-19) for /cti@22020000
OF: amba_device_add() failed (-19) for /funnel@220c0000
OF: amba_device_add() failed (-19) for /cpu-debug@22110000
OF: amba_device_add() failed (-19) for /etm@22140000
OF: amba_device_add() failed (-19) for /cti@22120000
OF: amba_device_add() failed (-19) for /cpu-debug@23010000
OF: amba_device_add() failed (-19) for /etm@23040000
OF: amba_device_add() failed (-19) for /cti@23020000
OF: amba_device_add() failed (-19) for /funnel@230c0000
OF: amba_device_add() failed (-19) for /cpu-debug@23110000
OF: amba_device_add() failed (-19) for /etm@23140000
OF: amba_device_add() failed (-19) for /cti@23120000
OF: amba_device_add() failed (-19) for /cpu-debug@23210000
OF: amba_device_add() failed (-19) for /etm@23240000
OF: amba_device_add() failed (-19) for /cti@23220000
OF: amba_device_add() failed (-19) for /cpu-debug@23310000
OF: amba_device_add() failed (-19) for /etm@23340000
OF: amba_device_add() failed (-19) for /cti@23320000
OF: amba_device_add() failed (-19) for /cti@20020000
OF: amba_device_add() failed (-19) for /cti@20110000
OF: amba_device_add() failed (-19) for /funnel@20130000
OF: amba_device_add() failed (-19) for /etf@20140000
OF: amba_device_add() failed (-19) for /funnel@20150000
OF: amba_device_add() failed (-19) for /cti@20160000

These are working fine with deferred probe in the mainline.
I tried the hack you have suggested here(rather Tony's version), also
tried with fw_devlink=0 and fw_devlink=1 && fw_devlink.strict=0
No change in the behaviour.

The DTS are in arch/arm64/boot/dts/arm/juno-*-scmi.dts and there
coresight devices are mostly in juno-cs-r1r2.dtsi

Let me know if there is anything obvious or you want me to bisect which
means I need more time. I can do that next week.

Saravana Kannan July 1, 2022, 7:13 p.m. UTC | #25

On Fri, Jul 1, 2022 at 8:08 AM Sudeep Holla <[e-mail]> wrote:
>
> Hi, Saravana,
>
> On Fri, Jul 01, 2022 at 01:26:12AM -0700, Saravana Kannan wrote:
>
> [...]
>
> > Can you check if this hack helps? If so, then I can think about
> > whether we can pick it up without breaking everything else. Copy-paste
> > tab mess up warning.
>
> Sorry for jumping in late and not even sure if this is right thread.
> I have not bisected anything yet, but I am seeing issues on my Juno R2
> with SCMI enabled power domains and Coresight AMBA devices.
>
> OF: amba_device_add() failed (-19) for /etf@20010000
> OF: amba_device_add() failed (-19) for /tpiu@20030000
> OF: amba_device_add() failed (-19) for /funnel@20040000
> OF: amba_device_add() failed (-19) for /etr@20070000
> OF: amba_device_add() failed (-19) for /stm@20100000
> OF: amba_device_add() failed (-19) for /replicator@20120000
> OF: amba_device_add() failed (-19) for /cpu-debug@22010000
> OF: amba_device_add() failed (-19) for /etm@22040000
> OF: amba_device_add() failed (-19) for /cti@22020000
> OF: amba_device_add() failed (-19) for /funnel@220c0000
> OF: amba_device_add() failed (-19) for /cpu-debug@22110000
> OF: amba_device_add() failed (-19) for /etm@22140000
> OF: amba_device_add() failed (-19) for /cti@22120000
> OF: amba_device_add() failed (-19) for /cpu-debug@23010000
> OF: amba_device_add() failed (-19) for /etm@23040000
> OF: amba_device_add() failed (-19) for /cti@23020000
> OF: amba_device_add() failed (-19) for /funnel@230c0000
> OF: amba_device_add() failed (-19) for /cpu-debug@23110000
> OF: amba_device_add() failed (-19) for /etm@23140000
> OF: amba_device_add() failed (-19) for /cti@23120000
> OF: amba_device_add() failed (-19) for /cpu-debug@23210000
> OF: amba_device_add() failed (-19) for /etm@23240000
> OF: amba_device_add() failed (-19) for /cti@23220000
> OF: amba_device_add() failed (-19) for /cpu-debug@23310000
> OF: amba_device_add() failed (-19) for /etm@23340000
> OF: amba_device_add() failed (-19) for /cti@23320000
> OF: amba_device_add() failed (-19) for /cti@20020000
> OF: amba_device_add() failed (-19) for /cti@20110000
> OF: amba_device_add() failed (-19) for /funnel@20130000
> OF: amba_device_add() failed (-19) for /etf@20140000
> OF: amba_device_add() failed (-19) for /funnel@20150000
> OF: amba_device_add() failed (-19) for /cti@20160000
>
> These are working fine with deferred probe in the mainline.
> I tried the hack you have suggested here(rather Tony's version),

Thanks for trying that.

> also
> tried with fw_devlink=0 and fw_devlink=1

0 and 1 aren't valid input to fw_devlink. But yeah, I don't expect
disabling it to make anything better.

> && fw_devlink.strict=0
> No change in the behaviour.
>
> The DTS are in arch/arm64/boot/dts/arm/juno-*-scmi.dts and there
> coresight devices are mostly in juno-cs-r1r2.dtsi

Thanks

> Let me know if there is anything obvious or you want me to bisect which
> means I need more time. I can do that next week.

I'll let you know once I poke at the DTS. We need to figure out why
fw_devlink wasn't blocking these from getting to the error (same as in
Tony's case). But since these are amba devices, I think I have some
guesses.

This is an old series that had some issues in some cases and I haven't
gotten around to looking at it. You can give that a shot if you can
apply it to a recent tree.
https://lore.kernel.org/lkml/[e-mail]/

After looking at that old patch again, I think I know what's going on.
For normal devices, the pm domain attach happens AFTER the device is
added and fw_devlink has had a chance to set up device links. And if
the suppliers aren't ready, really_probe() won't get as far as
dev_pm_domain_attach(). But for amba, the clock and pm domain
suppliers are "grabbed" before adding the device.

So with that old patch + always returning -EPROBE_DEFER in
amba_device_add() if amba_read_periphid() fails should fix your issue.

-Saravana

Alexander Stein July 4, 2022, 7:07 a.m. UTC | #26

Am Freitag, 1. Juli 2022, 09:02:22 CEST schrieb Saravana Kannan:
> On Thu, Jun 30, 2022 at 11:02 PM Alexander Stein
> 
> <[e-mail]> wrote:
> > Hi Saravana,
> > 
> > Am Freitag, 1. Juli 2022, 02:37:14 CEST schrieb Saravana Kannan:
> > > On Thu, Jun 23, 2022 at 5:08 AM Alexander Stein
> > > 
> > > <[e-mail]> wrote:
> > > > Hi,
> > > > 
> > > > Am Dienstag, 21. Juni 2022, 09:28:43 CEST schrieb Tony Lindgren:
> > > > > Hi,
> > > > > 
> > > > > * Saravana Kannan <[e-mail]> [700101 02:00]:
> > > > > > Now that fw_devlink=on by default and fw_devlink supports
> > > > > > "power-domains" property, the execution will never get to the
> > > > > > point
> > > > > > where driver_deferred_probe_check_state() is called before the
> > > > > > supplier
> > > > > > has probed successfully or before deferred probe timeout has
> > > > > > expired.
> > > > > > 
> > > > > > So, delete the call and replace it with -ENODEV.
> > > > > 
> > > > > Looks like this causes omaps to not boot in Linux next. With this
> > > > > simple-pm-bus fails to probe initially as the power-domain is not
> > > > > yet available. On platform_probe() genpd_get_from_provider() returns
> > > > > -ENOENT.
> > > > > 
> > > > > Seems like other stuff is potentially broken too, any ideas on
> > > > > how to fix this?
> > > > 
> > > > I think I'm hit by this as well, although I do not get a lockup.
> > > > In my case I'm using
> > > > arch/arm64/boot/dts/freescale/imx8mq-tqma8mq-mba8mx.dts and probing of
> > > > 38320000.blk-ctrl fails as the power-domain is not (yet) registed.
> > > 
> > > Ok, took a look.
> > > 
> > > The problem is that there are two drivers for the same device and they
> > > both initialize this device.
> > > 
> > >     gpc: gpc@303a0000 {
> > >     
> > >         compatible = "fsl,imx8mq-gpc";
> > >     
> > >     }
> > > 
> > > $ git grep -l "fsl,imx7d-gpc" -- drivers/
> > > drivers/irqchip/irq-imx-gpcv2.c
> > > drivers/soc/imx/gpcv2.c
> > > 
> > > IMHO, this is a bad/broken design.
> > > 
> > > So what's happening is that fw_devlink will block the probe of
> > > 38320000.blk-ctrl until 303a0000.gpc is initialized. And it stops
> > > blocking the probe of 38320000.blk-ctrl as soon as the first driver
> > > initializes the device. In this case, it's the irqchip driver.
> > > 
> > > I'd recommend combining these drivers into one. Something like the
> > > patch I'm attaching (sorry for the attachment, copy-paste is mangling
> > > the tabs). Can you give it a shot please?
> > 
> > I tried this patch and it delayed the driver initialization (those of UART
> > as
> > well BTW). Unfortunately the driver fails the same way:
> Thanks for testing the patch!
> 
> > > [    1.125253] imx8m-blk-ctrl 38320000.blk-ctrl: error -ENODEV: failed
> > > to
> > 
> > attach power domain "bus"
> > 
> > More than that it even introduced some more errors:
> > > [    0.008160] irq: no irq domain found for gpc@303a0000 !
> 
> So the idea behind my change was that as long as the irqchip isn't the
> root of the irqdomain (might be using the terms incorrectly) like the
> gic, you can make it a platform driver. And I was trying to hack up a
> patch that's the equivalent of platform_irqchip_probe() (which just
> ends up eventually calling the callback you use in IRQCHIP_DECLARE().
> I probably made some mistake in the quick hack that I'm sure if
> fixable.
> 
> > > [    0.013251] Failed to map interrupt for
> > > /soc@0/bus@30400000/timer@306a0000
> 
> However, this timer driver also uses TIMER_OF_DECLARE() which can't
> handle failure to get the IRQ (because it's can't -EPROBE_DEFER). So,
> this means, the timer driver inturn needs to be converted to a
> platform driver if it's supposed to work with the IRQCHIP_DECLARE()
> being converted to a platform driver.
> 
> But that's a can of worms not worth opening. But then I remembered
> this simpler workaround will work and it is pretty much a variant of
> the workaround that's already in the gpc's irqchip driver to allow two
> drivers to probe the same device (people really should stop doing
> that).
> 
> Can you drop my previous hack patch and try this instead please? I'm
> 99% sure this will work.
> 
> diff --git a/drivers/irqchip/irq-imx-gpcv2.c
> b/drivers/irqchip/irq-imx-gpcv2.c index b9c22f764b4d..8a0e82067924 100644
> --- a/drivers/irqchip/irq-imx-gpcv2.c
> +++ b/drivers/irqchip/irq-imx-gpcv2.c
> @@ -283,6 +283,7 @@ static int __init imx_gpcv2_irqchip_init(struct
> device_node *node,
>          * later the GPC power domain driver will not be skipped.
>          */
>         of_node_clear_flag(node, OF_POPULATED);
> +       fwnode_dev_initialized(domain->fwnode, false);
>         return 0;
>  }

Just to be sure here, I tried this patch on top of next-20220701 but 
unfortunately this doesn't fix the original problem either. The timer errors 
are gone though.
The probe of imx8m-blk-ctrl got slightly delayed (from 0.74 to 0.90s printk 
time) but results in the identical error message.

Best regards,
Alexander

Saravana Kannan July 5, 2022, 1:24 a.m. UTC | #27

On Mon, Jul 4, 2022 at 12:07 AM Alexander Stein
<[e-mail]> wrote:
>
> Am Freitag, 1. Juli 2022, 09:02:22 CEST schrieb Saravana Kannan:
> > On Thu, Jun 30, 2022 at 11:02 PM Alexander Stein
> >
> > <[e-mail]> wrote:
> > > Hi Saravana,
> > >
> > > Am Freitag, 1. Juli 2022, 02:37:14 CEST schrieb Saravana Kannan:
> > > > On Thu, Jun 23, 2022 at 5:08 AM Alexander Stein
> > > >
> > > > <[e-mail]> wrote:
> > > > > Hi,
> > > > >
> > > > > Am Dienstag, 21. Juni 2022, 09:28:43 CEST schrieb Tony Lindgren:
> > > > > > Hi,
> > > > > >
> > > > > > * Saravana Kannan <[e-mail]> [700101 02:00]:
> > > > > > > Now that fw_devlink=on by default and fw_devlink supports
> > > > > > > "power-domains" property, the execution will never get to the
> > > > > > > point
> > > > > > > where driver_deferred_probe_check_state() is called before the
> > > > > > > supplier
> > > > > > > has probed successfully or before deferred probe timeout has
> > > > > > > expired.
> > > > > > >
> > > > > > > So, delete the call and replace it with -ENODEV.
> > > > > >
> > > > > > Looks like this causes omaps to not boot in Linux next. With this
> > > > > > simple-pm-bus fails to probe initially as the power-domain is not
> > > > > > yet available. On platform_probe() genpd_get_from_provider() returns
> > > > > > -ENOENT.
> > > > > >
> > > > > > Seems like other stuff is potentially broken too, any ideas on
> > > > > > how to fix this?
> > > > >
> > > > > I think I'm hit by this as well, although I do not get a lockup.
> > > > > In my case I'm using
> > > > > arch/arm64/boot/dts/freescale/imx8mq-tqma8mq-mba8mx.dts and probing of
> > > > > 38320000.blk-ctrl fails as the power-domain is not (yet) registed.
> > > >
> > > > Ok, took a look.
> > > >
> > > > The problem is that there are two drivers for the same device and they
> > > > both initialize this device.
> > > >
> > > >     gpc: gpc@303a0000 {
> > > >
> > > >         compatible = "fsl,imx8mq-gpc";
> > > >
> > > >     }
> > > >
> > > > $ git grep -l "fsl,imx7d-gpc" -- drivers/
> > > > drivers/irqchip/irq-imx-gpcv2.c
> > > > drivers/soc/imx/gpcv2.c
> > > >
> > > > IMHO, this is a bad/broken design.
> > > >
> > > > So what's happening is that fw_devlink will block the probe of
> > > > 38320000.blk-ctrl until 303a0000.gpc is initialized. And it stops
> > > > blocking the probe of 38320000.blk-ctrl as soon as the first driver
> > > > initializes the device. In this case, it's the irqchip driver.
> > > >
> > > > I'd recommend combining these drivers into one. Something like the
> > > > patch I'm attaching (sorry for the attachment, copy-paste is mangling
> > > > the tabs). Can you give it a shot please?
> > >
> > > I tried this patch and it delayed the driver initialization (those of UART
> > > as
> > > well BTW). Unfortunately the driver fails the same way:
> > Thanks for testing the patch!
> >
> > > > [    1.125253] imx8m-blk-ctrl 38320000.blk-ctrl: error -ENODEV: failed
> > > > to
> > >
> > > attach power domain "bus"
> > >
> > > More than that it even introduced some more errors:
> > > > [    0.008160] irq: no irq domain found for gpc@303a0000 !
> >
> > So the idea behind my change was that as long as the irqchip isn't the
> > root of the irqdomain (might be using the terms incorrectly) like the
> > gic, you can make it a platform driver. And I was trying to hack up a
> > patch that's the equivalent of platform_irqchip_probe() (which just
> > ends up eventually calling the callback you use in IRQCHIP_DECLARE().
> > I probably made some mistake in the quick hack that I'm sure if
> > fixable.
> >
> > > > [    0.013251] Failed to map interrupt for
> > > > /soc@0/bus@30400000/timer@306a0000
> >
> > However, this timer driver also uses TIMER_OF_DECLARE() which can't
> > handle failure to get the IRQ (because it's can't -EPROBE_DEFER). So,
> > this means, the timer driver inturn needs to be converted to a
> > platform driver if it's supposed to work with the IRQCHIP_DECLARE()
> > being converted to a platform driver.
> >
> > But that's a can of worms not worth opening. But then I remembered
> > this simpler workaround will work and it is pretty much a variant of
> > the workaround that's already in the gpc's irqchip driver to allow two
> > drivers to probe the same device (people really should stop doing
> > that).
> >
> > Can you drop my previous hack patch and try this instead please? I'm
> > 99% sure this will work.
> >
> > diff --git a/drivers/irqchip/irq-imx-gpcv2.c
> > b/drivers/irqchip/irq-imx-gpcv2.c index b9c22f764b4d..8a0e82067924 100644
> > --- a/drivers/irqchip/irq-imx-gpcv2.c
> > +++ b/drivers/irqchip/irq-imx-gpcv2.c
> > @@ -283,6 +283,7 @@ static int __init imx_gpcv2_irqchip_init(struct
> > device_node *node,
> >          * later the GPC power domain driver will not be skipped.
> >          */
> >         of_node_clear_flag(node, OF_POPULATED);
> > +       fwnode_dev_initialized(domain->fwnode, false);
> >         return 0;
> >  }
>
> Just to be sure here, I tried this patch on top of next-20220701 but
> unfortunately this doesn't fix the original problem either. The timer errors
> are gone though.

To clarify, you had the timer issue only with my "combine drivers" patch, right?

> The probe of imx8m-blk-ctrl got slightly delayed (from 0.74 to 0.90s printk
> time) but results in the identical error message.

My guess is that the probe attempt of blk-ctrl is delayed now till gpc
probes (because of the device links getting created with the
fwnode_dev_initialized() fix), but by the time gpc probe finishes, the
power domains aren't registered yet because of the additional level of
device addition and probing.

Can you try the attached patch please?

And if that doesn't fix the issues, then enable the debug logs in the
following functions please and share the logs from boot till the
failure? If you can enable CONFIG_PRINTK_CALLER, that'd help too.
device_link_add()
fwnode_link_add()
fw_devlink_relax_cycle()

Btw, part of the reason I'm trying to make sure we fix it the right
way is that when we try to enable async boot by default, we don't run
into issues.

Thanks,
Saravana

Saravana Kannan July 5, 2022, 8:44 a.m. UTC | #28

On Fri, Jul 1, 2022 at 12:13 PM Saravana Kannan <[e-mail]> wrote:
>
> On Fri, Jul 1, 2022 at 8:08 AM Sudeep Holla <[e-mail]> wrote:
> >
> > Hi, Saravana,
> >
> > On Fri, Jul 01, 2022 at 01:26:12AM -0700, Saravana Kannan wrote:
> >
> > [...]
> >
> > > Can you check if this hack helps? If so, then I can think about
> > > whether we can pick it up without breaking everything else. Copy-paste
> > > tab mess up warning.
> >
> > Sorry for jumping in late and not even sure if this is right thread.
> > I have not bisected anything yet, but I am seeing issues on my Juno R2
> > with SCMI enabled power domains and Coresight AMBA devices.
> >
> > OF: amba_device_add() failed (-19) for /etf@20010000
> > OF: amba_device_add() failed (-19) for /tpiu@20030000
> > OF: amba_device_add() failed (-19) for /funnel@20040000
> > OF: amba_device_add() failed (-19) for /etr@20070000
> > OF: amba_device_add() failed (-19) for /stm@20100000
> > OF: amba_device_add() failed (-19) for /replicator@20120000
> > OF: amba_device_add() failed (-19) for /cpu-debug@22010000
> > OF: amba_device_add() failed (-19) for /etm@22040000
> > OF: amba_device_add() failed (-19) for /cti@22020000
> > OF: amba_device_add() failed (-19) for /funnel@220c0000
> > OF: amba_device_add() failed (-19) for /cpu-debug@22110000
> > OF: amba_device_add() failed (-19) for /etm@22140000
> > OF: amba_device_add() failed (-19) for /cti@22120000
> > OF: amba_device_add() failed (-19) for /cpu-debug@23010000
> > OF: amba_device_add() failed (-19) for /etm@23040000
> > OF: amba_device_add() failed (-19) for /cti@23020000
> > OF: amba_device_add() failed (-19) for /funnel@230c0000
> > OF: amba_device_add() failed (-19) for /cpu-debug@23110000
> > OF: amba_device_add() failed (-19) for /etm@23140000
> > OF: amba_device_add() failed (-19) for /cti@23120000
> > OF: amba_device_add() failed (-19) for /cpu-debug@23210000
> > OF: amba_device_add() failed (-19) for /etm@23240000
> > OF: amba_device_add() failed (-19) for /cti@23220000
> > OF: amba_device_add() failed (-19) for /cpu-debug@23310000
> > OF: amba_device_add() failed (-19) for /etm@23340000
> > OF: amba_device_add() failed (-19) for /cti@23320000
> > OF: amba_device_add() failed (-19) for /cti@20020000
> > OF: amba_device_add() failed (-19) for /cti@20110000
> > OF: amba_device_add() failed (-19) for /funnel@20130000
> > OF: amba_device_add() failed (-19) for /etf@20140000
> > OF: amba_device_add() failed (-19) for /funnel@20150000
> > OF: amba_device_add() failed (-19) for /cti@20160000
> >
> > These are working fine with deferred probe in the mainline.
> > I tried the hack you have suggested here(rather Tony's version),
>
> Thanks for trying that.
>
> > also
> > tried with fw_devlink=0 and fw_devlink=1
>
> 0 and 1 aren't valid input to fw_devlink. But yeah, I don't expect
> disabling it to make anything better.
>
> > && fw_devlink.strict=0
> > No change in the behaviour.
> >
> > The DTS are in arch/arm64/boot/dts/arm/juno-*-scmi.dts and there
> > coresight devices are mostly in juno-cs-r1r2.dtsi
>
> Thanks
>
> > Let me know if there is anything obvious or you want me to bisect which
> > means I need more time. I can do that next week.
>
> I'll let you know once I poke at the DTS. We need to figure out why
> fw_devlink wasn't blocking these from getting to the error (same as in
> Tony's case). But since these are amba devices, I think I have some
> guesses.
>
> This is an old series that had some issues in some cases and I haven't
> gotten around to looking at it. You can give that a shot if you can
> apply it to a recent tree.
> https://lore.kernel.org/lkml/[e-mail]/

I rebased it to driver-core-next and tested the patch  (for
correctness, not with your issue though). I'm fairly sure it should
help with your issue. Can you give it a shot please?

https://lore.kernel.org/lkml/[e-mail]/T/#u

-Saravana

>
> After looking at that old patch again, I think I know what's going on.
> For normal devices, the pm domain attach happens AFTER the device is
> added and fw_devlink has had a chance to set up device links. And if
> the suppliers aren't ready, really_probe() won't get as far as
> dev_pm_domain_attach(). But for amba, the clock and pm domain
> suppliers are "grabbed" before adding the device.
>
> So with that old patch + always returning -EPROBE_DEFER in
> amba_device_add() if amba_read_periphid() fails should fix your issue.
>
> -Saravana

Alexander Stein July 6, 2022, 1:02 p.m. UTC | #29

Am Dienstag, 5. Juli 2022, 03:24:33 CEST schrieb Saravana Kannan:
> On Mon, Jul 4, 2022 at 12:07 AM Alexander Stein
> 
> <[e-mail]> wrote:
> > Am Freitag, 1. Juli 2022, 09:02:22 CEST schrieb Saravana Kannan:
> > > On Thu, Jun 30, 2022 at 11:02 PM Alexander Stein
> > > 
> > > <[e-mail]> wrote:
> > > > Hi Saravana,
> > > > 
> > > > Am Freitag, 1. Juli 2022, 02:37:14 CEST schrieb Saravana Kannan:
> > > > > On Thu, Jun 23, 2022 at 5:08 AM Alexander Stein
> > > > > 
> > > > > <[e-mail]> wrote:
> > > > > > Hi,
> > > > > > 
> > > > > > Am Dienstag, 21. Juni 2022, 09:28:43 CEST schrieb Tony Lindgren:
> > > > > > > Hi,
> > > > > > > 
> > > > > > > * Saravana Kannan <[e-mail]> [700101 02:00]:
> > > > > > > > Now that fw_devlink=on by default and fw_devlink supports
> > > > > > > > "power-domains" property, the execution will never get to the
> > > > > > > > point
> > > > > > > > where driver_deferred_probe_check_state() is called before the
> > > > > > > > supplier
> > > > > > > > has probed successfully or before deferred probe timeout has
> > > > > > > > expired.
> > > > > > > > 
> > > > > > > > So, delete the call and replace it with -ENODEV.
> > > > > > > 
> > > > > > > Looks like this causes omaps to not boot in Linux next. With
> > > > > > > this
> > > > > > > simple-pm-bus fails to probe initially as the power-domain is
> > > > > > > not
> > > > > > > yet available. On platform_probe() genpd_get_from_provider()
> > > > > > > returns
> > > > > > > -ENOENT.
> > > > > > > 
> > > > > > > Seems like other stuff is potentially broken too, any ideas on
> > > > > > > how to fix this?
> > > > > > 
> > > > > > I think I'm hit by this as well, although I do not get a lockup.
> > > > > > In my case I'm using
> > > > > > arch/arm64/boot/dts/freescale/imx8mq-tqma8mq-mba8mx.dts and
> > > > > > probing of
> > > > > > 38320000.blk-ctrl fails as the power-domain is not (yet) registed.
> > > > > 
> > > > > Ok, took a look.
> > > > > 
> > > > > The problem is that there are two drivers for the same device and
> > > > > they
> > > > > both initialize this device.
> > > > > 
> > > > >     gpc: gpc@303a0000 {
> > > > >     
> > > > >         compatible = "fsl,imx8mq-gpc";
> > > > >     
> > > > >     }
> > > > > 
> > > > > $ git grep -l "fsl,imx7d-gpc" -- drivers/
> > > > > drivers/irqchip/irq-imx-gpcv2.c
> > > > > drivers/soc/imx/gpcv2.c
> > > > > 
> > > > > IMHO, this is a bad/broken design.
> > > > > 
> > > > > So what's happening is that fw_devlink will block the probe of
> > > > > 38320000.blk-ctrl until 303a0000.gpc is initialized. And it stops
> > > > > blocking the probe of 38320000.blk-ctrl as soon as the first driver
> > > > > initializes the device. In this case, it's the irqchip driver.
> > > > > 
> > > > > I'd recommend combining these drivers into one. Something like the
> > > > > patch I'm attaching (sorry for the attachment, copy-paste is
> > > > > mangling
> > > > > the tabs). Can you give it a shot please?
> > > > 
> > > > I tried this patch and it delayed the driver initialization (those of
> > > > UART
> > > > as
> > > 
> > > > well BTW). Unfortunately the driver fails the same way:
> > > Thanks for testing the patch!
> > > 
> > > > > [    1.125253] imx8m-blk-ctrl 38320000.blk-ctrl: error -ENODEV:
> > > > > failed
> > > > > to
> > > > 
> > > > attach power domain "bus"
> > > > 
> > > > More than that it even introduced some more errors:
> > > > > [    0.008160] irq: no irq domain found for gpc@303a0000 !
> > > 
> > > So the idea behind my change was that as long as the irqchip isn't the
> > > root of the irqdomain (might be using the terms incorrectly) like the
> > > gic, you can make it a platform driver. And I was trying to hack up a
> > > patch that's the equivalent of platform_irqchip_probe() (which just
> > > ends up eventually calling the callback you use in IRQCHIP_DECLARE().
> > > I probably made some mistake in the quick hack that I'm sure if
> > > fixable.
> > > 
> > > > > [    0.013251] Failed to map interrupt for
> > > > > /soc@0/bus@30400000/timer@306a0000
> > > 
> > > However, this timer driver also uses TIMER_OF_DECLARE() which can't
> > > handle failure to get the IRQ (because it's can't -EPROBE_DEFER). So,
> > > this means, the timer driver inturn needs to be converted to a
> > > platform driver if it's supposed to work with the IRQCHIP_DECLARE()
> > > being converted to a platform driver.
> > > 
> > > But that's a can of worms not worth opening. But then I remembered
> > > this simpler workaround will work and it is pretty much a variant of
> > > the workaround that's already in the gpc's irqchip driver to allow two
> > > drivers to probe the same device (people really should stop doing
> > > that).
> > > 
> > > Can you drop my previous hack patch and try this instead please? I'm
> > > 99% sure this will work.
> > > 
> > > diff --git a/drivers/irqchip/irq-imx-gpcv2.c
> > > b/drivers/irqchip/irq-imx-gpcv2.c index b9c22f764b4d..8a0e82067924
> > > 100644
> > > --- a/drivers/irqchip/irq-imx-gpcv2.c
> > > +++ b/drivers/irqchip/irq-imx-gpcv2.c
> > > @@ -283,6 +283,7 @@ static int __init imx_gpcv2_irqchip_init(struct
> > > device_node *node,
> > > 
> > >          * later the GPC power domain driver will not be skipped.
> > >          */
> > >         
> > >         of_node_clear_flag(node, OF_POPULATED);
> > > 
> > > +       fwnode_dev_initialized(domain->fwnode, false);
> > > 
> > >         return 0;
> > >  
> > >  }
> > 
> > Just to be sure here, I tried this patch on top of next-20220701 but
> > unfortunately this doesn't fix the original problem either. The timer
> > errors are gone though.
> 
> To clarify, you had the timer issue only with my "combine drivers" patch,
> right?

That's correct.

> > The probe of imx8m-blk-ctrl got slightly delayed (from 0.74 to 0.90s
> > printk
> > time) but results in the identical error message.
> 
> My guess is that the probe attempt of blk-ctrl is delayed now till gpc
> probes (because of the device links getting created with the
> fwnode_dev_initialized() fix), but by the time gpc probe finishes, the
> power domains aren't registered yet because of the additional level of
> device addition and probing.
> 
> Can you try the attached patch please?

Sure, it needed some small fixes though. But the error still is present.

> And if that doesn't fix the issues, then enable the debug logs in the
> following functions please and share the logs from boot till the
> failure? If you can enable CONFIG_PRINTK_CALLER, that'd help too.
> device_link_add()
> fwnode_link_add()
> fw_devlink_relax_cycle()

I switched fw_devlink_relax_cycle() for fw_devlink_relax_link() as the former 
has no debug output here.

For the record I added the following line to my kernel command line:
> dyndbg="func device_link_add +p; func fwnode_link_add +p; func 
fw_devlink_relax_link +p"

I attached the dmesg until the probe error to this mail. But I noticed the 
following lines which seem interesting:
> [    1.466620][    T8] imx-pgc imx-pgc-domain.5: Linked as a consumer to
> regulator.8
> [    1.466743][    T8] imx-pgc imx-pgc-domain.5: imx_pgc_domain_probe: Probe 
succeeded
> [    1.474733][    T8] imx-pgc imx-pgc-domain.6: Linked as a consumer to 
regulator.9
> [    1.474774][    T8] imx-pgc imx-pgc-domain.6: imx_pgc_domain_probe: Probe 
succeeded

regulator.8 and regulator.9 is the power sequencer, attached on I2C. This also 
makes perfectly sense if you look at [1]ff. These power domains are supplied 
by specific power supply rails. Several, if not all, imx8mq boards have this 
kind of setting.

> Btw, part of the reason I'm trying to make sure we fix it the right
> way is that when we try to enable async boot by default, we don't run
> into issues.

Sounds resonable.

Best regards,
Alexander

[1] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/
arch/arm64/boot/dts/freescale/imx8mq-tqma8mq.dtsi#n84
[    0.000000][    T0] Booting Linux on physical CPU 0x0000000000 [0x410fd034]
[    0.000000][    T0] Linux version 5.19.0-rc5-next-20220706+ (steina@steina-w) (aarch64-v8a-linux-gnu-gcc (OSELAS.Toolchain-2020.08.0 10-20200822) 10.2.1 20200822, GNU ld (GNU Binutils) 2.35) #422 SMP PREEMPT Wed Jul 6 14:43:55 CEST 2022
[    0.000000][    T0] Machine model: TQ-Systems GmbH i.MX8MQ TQMa8MQ on MBa8Mx
[    0.000000][    T0] earlycon: ec_imx6q0 at MMIO 0x0000000030880000 (options '115200')
[    0.000000][    T0] printk: bootconsole [ec_imx6q0] enabled
[    0.000000][    T0] efi: UEFI not found.
[    0.000000][    T0] Reserved memory: created CMA memory pool at 0x0000000090000000, size 640 MiB
[    0.000000][    T0] OF: reserved mem: initialized node linux,cma, compatible id shared-dma-pool
[    0.000000][    T0] NUMA: No NUMA configuration found
[    0.000000][    T0] NUMA: Faking a node at [mem 0x0000000040000000-0x000000013fffffff]
[    0.000000][    T0] NUMA: NODE_DATA [mem 0x13f7beb40-0x13f7c0fff]
[    0.000000][    T0] Zone ranges:
[    0.000000][    T0]   DMA      [mem 0x0000000040000000-0x00000000ffffffff]
[    0.000000][    T0]   DMA32    empty
[    0.000000][    T0]   Normal   [mem 0x0000000100000000-0x000000013fffffff]
[    0.000000][    T0] Movable zone start for each node
[    0.000000][    T0] Early memory node ranges
[    0.000000][    T0]   node   0: [mem 0x0000000040000000-0x000000013fffffff]
[    0.000000][    T0] Initmem setup node 0 [mem 0x0000000040000000-0x000000013fffffff]
[    0.000000][    T0] psci: probing for conduit method from DT.
[    0.000000][    T0] psci: PSCIv1.1 detected in firmware.
[    0.000000][    T0] psci: Using standard PSCI v0.2 function IDs
[    0.000000][    T0] psci: MIGRATE_INFO_TYPE not supported.
[    0.000000][    T0] psci: SMC Calling Convention v1.1
[    0.000000][    T0] percpu: Embedded 19 pages/cpu s38376 r8192 d31256 u77824
[    0.000000][    T0] pcpu-alloc: s38376 r8192 d31256 u77824 alloc=19*4096
[    0.000000][    T0] pcpu-alloc: [0] 0 [0] 1 [0] 2 [0] 3 
[    0.000000][    T0] Detected VIPT I-cache on CPU0
[    0.000000][    T0] CPU features: detected: GIC system register CPU interface
[    0.000000][    T0] CPU features: detected: ARM erratum 845719
[    0.000000][    T0] Fallback order for Node 0: 0 
[    0.000000][    T0] Built 1 zonelists, mobility grouping on.  Total pages: 1032192
[    0.000000][    T0] Policy zone: Normal
[    0.000000][    T0] Kernel command line: root=/dev/nfs rw nfsroot=192.168.0.101:/srv/tftp/imx8_mainline,v3,tcp ip=192.168.0.100:192.168.0.101::::eth0:off console=ttymxc2,115200 earlycon=ec_imx6q,0x30880000,115200 dyndbg="func device_link_add +p; func fwnode_link_add +p; func fw_devlink_relax_link +p"
[    0.000000][    T0] Dentry cache hash table entries: 524288 (order: 10, 4194304 bytes, linear)
[    0.000000][    T0] Inode-cache hash table entries: 262144 (order: 9, 2097152 bytes, linear)
[    0.000000][    T0] mem auto-init: stack:off, heap alloc:off, heap free:off
[    0.000000][    T0] software IO TLB: mapped [mem 0x00000000fbfff000-0x00000000fffff000] (64MB)
[    0.000000][    T0] Memory: 3363428K/4194304K available (14016K kernel code, 2190K rwdata, 6540K rodata, 5312K init, 494K bss, 175516K reserved, 655360K cma-reserved)
[    0.000000][    T0] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=4, Nodes=1
[    0.000000][    T0] rcu: Preemptible hierarchical RCU implementation.
[    0.000000][    T0] rcu: 	RCU event tracing is enabled.
[    0.000000][    T0] rcu: 	RCU restricting CPUs from NR_CPUS=256 to nr_cpu_ids=4.
[    0.000000][    T0] 	Trampoline variant of Tasks RCU enabled.
[    0.000000][    T0] 	Tracing variant of Tasks RCU enabled.
[    0.000000][    T0] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
[    0.000000][    T0] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=4
[    0.000000][    T0] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
[    0.000000][    T0] GICv3: GIC: Using split EOI/Deactivate mode
[    0.000000][    T0] GICv3: 128 SPIs implemented
[    0.000000][    T0] GICv3: 0 Extended SPIs implemented
[    0.000000][    T0] Root IRQ handler: gic_handle_irq
[    0.000000][    T0] GICv3: GICv3 features: 16 PPIs
[    0.000000][    T0] GICv3: CPU0: found redistributor 0 region 0:0x0000000038880000
[    0.000000][    T0] ITS: No ITS available, not enabling LPIs
[    0.000000][    T0] rcu: srcu_init: Setting srcu_struct sizes based on contention.
[    0.000000][    T0] arch_timer: cp15 timer(s) running at 8.33MHz (phys).
[    0.000000][    T0] clocksource: arch_sys_counter: mask: 0xffffffffffffff max_cycles: 0x1ec0311ec, max_idle_ns: 440795202152 ns
[    0.000001][    T0] sched_clock: 56 bits at 8MHz, resolution 120ns, wraps every 2199023255541ns
[    0.009211][    T0] Console: colour dummy device 80x25
[    0.013967][    T0] Calibrating delay loop (skipped), value calculated using timer frequency.. 16.66 BogoMIPS (lpj=33333)
[    0.024859][    T0] pid_max: default: 32768 minimum: 301
[    0.030261][    T0] LSM: Security Framework initializing
[    0.035625][    T0] Mount-cache hash table entries: 8192 (order: 4, 65536 bytes, linear)
[    0.043622][    T0] Mountpoint-cache hash table entries: 8192 (order: 4, 65536 bytes, linear)
[    0.054209][    T1] cblist_init_generic: Setting adjustable number of callback queues.
[    0.060116][    T1] cblist_init_generic: Setting shift to 2 and lim to 1.
[    0.066983][    T1] cblist_init_generic: Setting shift to 2 and lim to 1.
[    0.073902][    T1] rcu: Hierarchical SRCU implementation.
[    0.079195][    T1] rcu: 	Max phase no-delay instances is 1000.
[    0.087737][    T1] EFI services will not be available.
[    0.090823][    T1] smp: Bringing up secondary CPUs ...
[    0.096224][    T0] Detected VIPT I-cache on CPU1
[    0.096283][    T0] GICv3: CPU1: found redistributor 1 region 0:0x00000000388a0000
[    0.096337][    T0] CPU1: Booted secondary processor 0x0000000001 [0x410fd034]
[    0.097001][    T0] Detected VIPT I-cache on CPU2
[    0.097041][    T0] GICv3: CPU2: found redistributor 2 region 0:0x00000000388c0000
[    0.097069][    T0] CPU2: Booted secondary processor 0x0000000002 [0x410fd034]
[    0.097672][    T0] Detected VIPT I-cache on CPU3
[    0.097711][    T0] GICv3: CPU3: found redistributor 3 region 0:0x00000000388e0000
[    0.097739][    T0] CPU3: Booted secondary processor 0x0000000003 [0x410fd034]
[    0.097832][    T1] smp: Brought up 1 node, 4 CPUs
[    0.158985][    T1] SMP: Total of 4 processors activated.
[    0.164380][    T1] CPU features: detected: 32-bit EL0 Support
[    0.170245][    T1] CPU features: detected: CRC32 instructions
[    0.176396][    T1] CPU: All CPU(s) started at EL2
[    0.180899][   T14] alternatives: patching kernel code
[    0.188121][    T1] devtmpfs: initialized
[    0.199468][    T1] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns
[    0.207118][    T1] futex hash table entries: 1024 (order: 4, 65536 bytes, linear)
[    0.239390][    T1] pinctrl core: initialized pinctrl subsystem
[    0.245118][    T1] DMI not present or invalid.
[    0.247854][    T1] NET: Registered PF_NETLINK/PF_ROUTE protocol family
[    0.254831][    T1] DMA: preallocated 512 KiB GFP_KERNEL pool for atomic allocations
[    0.261589][    T1] DMA: preallocated 512 KiB GFP_KERNEL|GFP_DMA pool for atomic allocations
[    0.270133][    T1] DMA: preallocated 512 KiB GFP_KERNEL|GFP_DMA32 pool for atomic allocations
[    0.278564][    T1] audit: initializing netlink subsys (disabled)
[    0.284869][   T34] audit: type=2000 audit(0.184:1): state=initialized audit_enabled=0 res=1
[    0.285423][    T1] thermal_sys: Registered thermal governor 'bang_bang'
[    0.293086][    T1] thermal_sys: Registered thermal governor 'step_wise'
[    0.299794][    T1] thermal_sys: Registered thermal governor 'power_allocator'
[    0.306986][    T1] cpuidle: using governor menu
[    0.318580][    T1] hw-breakpoint: found 6 breakpoint and 4 watchpoint registers.
[    0.325965][    T1] ASID allocator initialised with 65536 entries
[    0.333008][    T1] Serial: AMBA PL011 UART driver
[    0.337902][    T1] gpio@30200000 Linked as a fwnode consumer to gpc@303a0000
[    0.337943][    T1] gpio@30200000 Linked as a fwnode consumer to clock-controller@30380000
[    0.338004][    T1] gpio@30210000 Linked as a fwnode consumer to gpc@303a0000
[    0.338038][    T1] gpio@30210000 Linked as a fwnode consumer to clock-controller@30380000
[    0.338098][    T1] gpio@30220000 Linked as a fwnode consumer to gpc@303a0000
[    0.338132][    T1] gpio@30220000 Linked as a fwnode consumer to clock-controller@30380000
[    0.338192][    T1] gpio@30230000 Linked as a fwnode consumer to gpc@303a0000
[    0.338227][    T1] gpio@30230000 Linked as a fwnode consumer to clock-controller@30380000
[    0.338284][    T1] gpio@30240000 Linked as a fwnode consumer to gpc@303a0000
[    0.338317][    T1] gpio@30240000 Linked as a fwnode consumer to clock-controller@30380000
[    0.338378][    T1] tmu@30260000 Linked as a fwnode consumer to gpc@303a0000
[    0.338398][    T1] tmu@30260000 Linked as a fwnode consumer to clock-controller@30380000
[    0.338455][    T1] watchdog@30280000 Linked as a fwnode consumer to gpc@303a0000
[    0.338475][    T1] watchdog@30280000 Linked as a fwnode consumer to clock-controller@30380000
[    0.338502][    T1] watchdog@30280000 Linked as a fwnode consumer to pinctrl@30330000
[    0.338549][    T1] sdma@302c0000 Linked as a fwnode consumer to gpc@303a0000
[    0.338571][    T1] sdma@302c0000 Linked as a fwnode consumer to clock-controller@30380000
[    0.338984][    T1] efuse@30350000 Linked as a fwnode consumer to clock-controller@30380000
[    0.339058][    T1] syscon@30360000 Linked as a fwnode consumer to gpc@303a0000
[    0.339120][    T1] snvs-rtc-lp Linked as a fwnode consumer to gpc@303a0000
[    0.339154][    T1] snvs-rtc-lp Linked as a fwnode consumer to clock-controller@30380000
[    0.339199][    T1] snvs-powerkey Linked as a fwnode consumer to gpc@303a0000
[    0.339226][    T1] snvs-powerkey Linked as a fwnode consumer to clock-controller@30380000
[    0.339278][    T1] clock-controller@30380000 Linked as a fwnode consumer to gpc@303a0000
[    0.339392][    T1] reset-controller@30390000 Linked as a fwnode consumer to gpc@303a0000
[    0.339497][    T1] power-domain@1 Linked as a fwnode consumer to gpc@303a0000
[    0.339564][    T1] power-domain@5 Linked as a fwnode consumer to clock-controller@30380000
[    0.339601][    T1] power-domain@5 Linked as a fwnode consumer to pmic@8
[    0.339631][    T1] power-domain@6 Linked as a fwnode consumer to clock-controller@30380000
[    0.339672][    T1] power-domain@6 Linked as a fwnode consumer to pmic@8
[    0.339786][    T1] pwm@30680000 Linked as a fwnode consumer to gpc@303a0000
[    0.339809][    T1] pwm@30680000 Linked as a fwnode consumer to clock-controller@30380000
[    0.339845][    T1] pwm@30680000 Linked as a fwnode consumer to pinctrl@30330000
[    0.339886][    T1] pwm@30690000 Linked as a fwnode consumer to gpc@303a0000
[    0.339906][    T1] pwm@30690000 Linked as a fwnode consumer to clock-controller@30380000
[    0.339942][    T1] pwm@30690000 Linked as a fwnode consumer to pinctrl@30330000
[    0.339985][    T1] timer@306a0000 Linked as a fwnode consumer to gpc@303a0000
[    0.340064][    T1] spi@30820000 Linked as a fwnode consumer to gpc@303a0000
[    0.340085][    T1] spi@30820000 Linked as a fwnode consumer to clock-controller@30380000
[    0.340114][    T1] spi@30820000 Linked as a fwnode consumer to sdma@30bd0000
[    0.340146][    T1] spi@30820000 Linked as a fwnode consumer to pinctrl@30330000
[    0.340167][    T1] spi@30820000 Linked as a fwnode consumer to gpio@30240000
[    0.340218][    T1] spi@30830000 Linked as a fwnode consumer to gpc@303a0000
[    0.340240][    T1] spi@30830000 Linked as a fwnode consumer to clock-controller@30380000
[    0.340266][    T1] spi@30830000 Linked as a fwnode consumer to sdma@30bd0000
[    0.340300][    T1] spi@30830000 Linked as a fwnode consumer to pinctrl@30330000
[    0.340319][    T1] spi@30830000 Linked as a fwnode consumer to gpio@30240000
[    0.340364][    T1] serial@30860000 Linked as a fwnode consumer to gpc@303a0000
[    0.340386][    T1] serial@30860000 Linked as a fwnode consumer to clock-controller@30380000
[    0.340419][    T1] serial@30860000 Linked as a fwnode consumer to pinctrl@30330000
[    0.340468][    T1] serial@30880000 Linked as a fwnode consumer to gpc@303a0000
[    0.340489][    T1] serial@30880000 Linked as a fwnode consumer to clock-controller@30380000
[    0.340524][    T1] serial@30880000 Linked as a fwnode consumer to pinctrl@30330000
[    0.340572][    T1] serial@30890000 Linked as a fwnode consumer to gpc@303a0000
[    0.340599][    T1] serial@30890000 Linked as a fwnode consumer to clock-controller@30380000
[    0.340635][    T1] serial@30890000 Linked as a fwnode consumer to pinctrl@30330000
[    0.340690][    T1] sai@308c0000 Linked as a fwnode consumer to gpc@303a0000
[    0.340712][    T1] sai@308c0000 Linked as a fwnode consumer to clock-controller@30380000
[    0.340782][    T1] sai@308c0000 Linked as a fwnode consumer to sdma@30bd0000
[    0.340817][    T1] sai@308c0000 Linked as a fwnode consumer to pinctrl@30330000
[    0.340880][    T1] crypto@30900000 Linked as a fwnode consumer to gpc@303a0000
[    0.340903][    T1] crypto@30900000 Linked as a fwnode consumer to clock-controller@30380000
[    0.340953][    T1] jr@2000 Linked as a fwnode consumer to gpc@303a0000
[    0.341002][    T1] jr@3000 Linked as a fwnode consumer to gpc@303a0000
[    0.341053][    T1] i2c@30a20000 Linked as a fwnode consumer to gpc@303a0000
[    0.341074][    T1] i2c@30a20000 Linked as a fwnode consumer to clock-controller@30380000
[    0.341109][    T1] i2c@30a20000 Linked as a fwnode consumer to pinctrl@30330000
[    0.341136][    T1] i2c@30a20000 Linked as a fwnode consumer to gpio@30240000
[    0.341384][    T1] rtc@51 Linked as a fwnode consumer to pinctrl@30330000
[    0.341404][    T1] rtc@51 Linked as a fwnode consumer to gpio@30200000
[    0.341513][    T1] gpio@23 Linked as a fwnode consumer to regulator-3v3
[    0.341529][    T1] gpio@23 Linked as a fwnode consumer to gpio@30200000
[    0.341641][    T1] gpio@24 Linked as a fwnode consumer to regulator-3v3
[    0.341678][    T1] gpio@25 Linked as a fwnode consumer to regulator-3v3
[    0.341698][    T1] gpio@25 Linked as a fwnode consumer to pinctrl@30330000
[    0.341714][    T1] gpio@25 Linked as a fwnode consumer to gpio@30200000
[    0.341800][    T1] i2c@30a30000 Linked as a fwnode consumer to gpc@303a0000
[    0.341821][    T1] i2c@30a30000 Linked as a fwnode consumer to clock-controller@30380000
[    0.341857][    T1] i2c@30a30000 Linked as a fwnode consumer to pinctrl@30330000
[    0.341885][    T1] i2c@30a30000 Linked as a fwnode consumer to gpio@30240000
[    0.341927][    T1] audio-codec@18 Linked as a fwnode consumer to gpio@25
[    0.341945][    T1] audio-codec@18 Linked as a fwnode consumer to regulator-3v3
[    0.341972][    T1] audio-codec@18 Linked as a fwnode consumer to clock-controller@30380000
[    0.342044][    T1] i2c@30a40000 Linked as a fwnode consumer to gpc@303a0000
[    0.342066][    T1] i2c@30a40000 Linked as a fwnode consumer to clock-controller@30380000
[    0.342100][    T1] i2c@30a40000 Linked as a fwnode consumer to pinctrl@30330000
[    0.342133][    T1] i2c@30a40000 Linked as a fwnode consumer to gpio@30240000
[    0.342192][    T1] mailbox@30aa0000 Linked as a fwnode consumer to gpc@303a0000
[    0.342213][    T1] mailbox@30aa0000 Linked as a fwnode consumer to clock-controller@30380000
[    0.342261][    T1] mmc@30b40000 Linked as a fwnode consumer to gpc@303a0000
[    0.342284][    T1] mmc@30b40000 Linked as a fwnode consumer to clock-controller@30380000
[    0.342333][    T1] mmc@30b40000 Linked as a fwnode consumer to pinctrl@30330000
[    0.342377][    T1] mmc@30b40000 Linked as a fwnode consumer to regulator-vcc3v3
[    0.342397][    T1] mmc@30b40000 Linked as a fwnode consumer to regulator-vcc1v8
[    0.342443][    T1] mmc@30b50000 Linked as a fwnode consumer to gpc@303a0000
[    0.342467][    T1] mmc@30b50000 Linked as a fwnode consumer to clock-controller@30380000
[    0.342515][    T1] mmc@30b50000 Linked as a fwnode consumer to pinctrl@30330000
[    0.342563][    T1] mmc@30b50000 Linked as a fwnode consumer to gpio@30210000
[    0.342592][    T1] mmc@30b50000 Linked as a fwnode consumer to regulator-vmmc
[    0.342634][    T1] sdma@30bd0000 Linked as a fwnode consumer to gpc@303a0000
[    0.342655][    T1] sdma@30bd0000 Linked as a fwnode consumer to clock-controller@30380000
[    0.342720][    T1] ethernet@30be0000 Linked as a fwnode consumer to gpc@303a0000
[    0.342783][    T1] ethernet@30be0000 Linked as a fwnode consumer to clock-controller@30380000
[    0.342843][    T1] ethernet@30be0000 Linked as a fwnode consumer to efuse@30350000
[    0.342874][    T1] ethernet@30be0000 Linked as a fwnode consumer to pinctrl@30330000
[    0.342901][    T1] ethernet@30be0000 Linked as a fwnode consumer to regulator-3v3
[    0.342969][    T1] ethernet-phy@e Linked as a fwnode consumer to gpio@25
[    0.343008][    T1] interconnect@32700000 Linked as a fwnode consumer to clock-controller@30380000
[    0.343113][    T1] interrupt-controller@32e2d000 Linked as a fwnode consumer to gpc@303a0000
[    0.343135][    T1] interrupt-controller@32e2d000 Linked as a fwnode consumer to clock-controller@30380000
[    0.343193][    T1] gpu@38000000 Linked as a fwnode consumer to gpc@303a0000
[    0.343214][    T1] gpu@38000000 Linked as a fwnode consumer to clock-controller@30380000
[    0.343288][    T1] usb@38100000 Linked as a fwnode consumer to clock-controller@30380000
[    0.343342][    T1] usb@38100000 Linked as a fwnode consumer to gpc@303a0000
[    0.343367][    T1] usb@38100000 Linked as a fwnode consumer to usb-phy@381f0040
[    0.343407][    T1] usb@38100000 Linked as a fwnode consumer to extcon-usbotg0
[    0.343450][    T1] usb-phy@381f0040 Linked as a fwnode consumer to clock-controller@30380000
[    0.343489][    T1] usb-phy@381f0040 Linked as a fwnode consumer to regulator-otg-vbus
[    0.343529][    T1] usb@38200000 Linked as a fwnode consumer to clock-controller@30380000
[    0.343582][    T1] usb@38200000 Linked as a fwnode consumer to gpc@303a0000
[    0.343606][    T1] usb@38200000 Linked as a fwnode consumer to usb-phy@382f0040
[    0.343659][    T1] usb-phy@382f0040 Linked as a fwnode consumer to clock-controller@30380000
[    0.343723][    T1] video-codec@38300000 Linked as a fwnode consumer to gpc@303a0000
[    0.343745][    T1] video-codec@38300000 Linked as a fwnode consumer to clock-controller@30380000
[    0.343779][    T1] video-codec@38300000 Linked as a fwnode consumer to blk-ctrl@38320000
[    0.343823][    T1] video-codec@38310000 Linked as a fwnode consumer to gpc@303a0000
[    0.343845][    T1] video-codec@38310000 Linked as a fwnode consumer to clock-controller@30380000
[    0.343870][    T1] video-codec@38310000 Linked as a fwnode consumer to blk-ctrl@38320000
[    0.343905][    T1] blk-ctrl@38320000 Linked as a fwnode consumer to gpc@303a0000
[    0.343943][    T1] blk-ctrl@38320000 Linked as a fwnode consumer to clock-controller@30380000
[    0.344029][    T1] pcie@33800000 Linked as a fwnode consumer to gpc@303a0000
[    0.344086][    T1] pcie@33800000 Linked as a fwnode consumer to reset-controller@30390000
[    0.344133][    T1] pcie@33800000 Linked as a fwnode consumer to pmic@8
[    0.344153][    T1] pcie@33800000 Linked as a fwnode consumer to gpio@23
[    0.344173][    T1] pcie@33800000 Linked as a fwnode consumer to clock-controller@30380000
[    0.344216][    T1] pcie@33800000 Linked as a fwnode consumer to regulator-3v3
[    0.344283][    T1] pcie@33c00000 Linked as a fwnode consumer to gpc@303a0000
[    0.344335][    T1] pcie@33c00000 Linked as a fwnode consumer to reset-controller@30390000
[    0.344382][    T1] pcie@33c00000 Linked as a fwnode consumer to pmic@8
[    0.344399][    T1] pcie@33c00000 Linked as a fwnode consumer to clock-controller@30380000
[    0.344442][    T1] pcie@33c00000 Linked as a fwnode consumer to regulator-3v3
[    0.346535][    T1] platform 30280000.watchdog: Linked as a consumer to 30330000.pinctrl
[    0.347193][    T1] imx8mq-pinctrl 30330000.pinctrl: initialized IMX pinctrl driver
[    0.353405][    T1] platform 30370000.snvs:snvs-powerkey: Linked as a consumer to 30380000.clock-controller
[    0.353484][    T1] platform 30370000.snvs:snvs-rtc-lp: Linked as a consumer to 30380000.clock-controller
[    0.353556][    T1] platform 30350000.efuse: Linked as a consumer to 30380000.clock-controller
[    0.353634][    T1] platform 302c0000.sdma: Linked as a consumer to 30380000.clock-controller
[    0.353706][    T1] platform 30280000.watchdog: Linked as a consumer to 30380000.clock-controller
[    0.353778][    T1] platform 30260000.tmu: Linked as a consumer to 30380000.clock-controller
[    0.353855][    T1] platform 30240000.gpio: Linked as a consumer to 30380000.clock-controller
[    0.353926][    T1] platform 30230000.gpio: Linked as a consumer to 30380000.clock-controller
[    0.354007][    T1] platform 30220000.gpio: Linked as a consumer to 30380000.clock-controller
[    0.354091][    T1] platform 30210000.gpio: Linked as a consumer to 30380000.clock-controller
[    0.354162][    T1] platform 30200000.gpio: Linked as a consumer to 30380000.clock-controller
[    0.354603][    T1] platform 30390000.reset-controller: Linked as a consumer to 303a0000.gpc
[    0.354688][    T1] platform 30380000.clock-controller: Linked as a consumer to 303a0000.gpc
[    0.354761][    T1] platform 30370000.snvs:snvs-powerkey: Linked as a consumer to 303a0000.gpc
[    0.354842][    T1] platform 30370000.snvs:snvs-rtc-lp: Linked as a consumer to 303a0000.gpc
[    0.354913][    T1] platform 30360000.syscon: Linked as a consumer to 303a0000.gpc
[    0.354982][    T1] platform 302c0000.sdma: Linked as a consumer to 303a0000.gpc
[    0.355058][    T1] platform 30280000.watchdog: Linked as a consumer to 303a0000.gpc
[    0.355128][    T1] platform 30260000.tmu: Linked as a consumer to 303a0000.gpc
[    0.355197][    T1] platform 30240000.gpio: Linked as a consumer to 303a0000.gpc
[    0.355276][    T1] platform 30230000.gpio: Linked as a consumer to 303a0000.gpc
[    0.355346][    T1] platform 30220000.gpio: Linked as a consumer to 303a0000.gpc
[    0.355431][    T1] platform 30210000.gpio: Linked as a consumer to 303a0000.gpc
[    0.355504][    T1] platform 30200000.gpio: Linked as a consumer to 303a0000.gpc
[    0.355584][    T1] platform 303a0000.gpc: Linked as a sync state only consumer to 30380000.clock-controller
[    0.355809][    T1] platform 30400000.bus: Linked as a sync state only consumer to 30330000.pinctrl
[    0.355879][    T1] platform 30400000.bus: Linked as a sync state only consumer to 30380000.clock-controller
[    0.355977][    T1] platform 30400000.bus: Linked as a sync state only consumer to 303a0000.gpc
[    0.356232][    T1] platform 30680000.pwm: Linked as a consumer to 30330000.pinctrl
[    0.356338][    T1] platform 30680000.pwm: Linked as a consumer to 30380000.clock-controller
[    0.356408][    T1] platform 30680000.pwm: Linked as a consumer to 303a0000.gpc
[    0.356650][    T1] platform 30690000.pwm: Linked as a consumer to 30330000.pinctrl
[    0.356762][    T1] platform 30690000.pwm: Linked as a consumer to 30380000.clock-controller
[    0.356834][    T1] platform 30690000.pwm: Linked as a consumer to 303a0000.gpc
[    0.357081][    T1] platform 306a0000.timer: Linked as a consumer to 303a0000.gpc
[    0.357380][    T1] platform 30800000.bus: Linked as a sync state only consumer to 30240000.gpio
[    0.357449][    T1] platform 30800000.bus: Linked as a sync state only consumer to 30330000.pinctrl
[    0.357520][    T1] platform 30800000.bus: Linked as a sync state only consumer to 30380000.clock-controller
[    0.357597][    T1] platform 30800000.bus: Linked as a sync state only consumer to 303a0000.gpc
[    0.357726][    T1] platform 30800000.bus: Linked as a sync state only consumer to 30200000.gpio
[    0.357837][    T1] platform 30800000.bus: Linked as a sync state only consumer to 30210000.gpio
[    0.357922][    T1] platform 30800000.bus: Linked as a sync state only consumer to 30350000.efuse
[    0.358158][    T1] platform 30820000.spi: Linked as a consumer to 30240000.gpio
[    0.358231][    T1] platform 30820000.spi: Linked as a consumer to 30330000.pinctrl
[    0.358335][    T1] platform 30820000.spi: Linked as a consumer to 30380000.clock-controller
[    0.358418][    T1] platform 30820000.spi: Linked as a consumer to 303a0000.gpc
[    0.358666][    T1] platform 30830000.spi: Linked as a consumer to 30240000.gpio
[    0.358741][    T1] platform 30830000.spi: Linked as a consumer to 30330000.pinctrl
[    0.358851][    T1] platform 30830000.spi: Linked as a consumer to 30380000.clock-controller
[    0.358927][    T1] platform 30830000.spi: Linked as a consumer to 303a0000.gpc
[    0.359177][    T1] platform 30860000.serial: Linked as a consumer to 30330000.pinctrl
[    0.359287][    T1] platform 30860000.serial: Linked as a consumer to 30380000.clock-controller
[    0.359356][    T1] platform 30860000.serial: Linked as a consumer to 303a0000.gpc
[    0.359601][    T1] platform 30880000.serial: Linked as a consumer to 30330000.pinctrl
[    0.359706][    T1] platform 30880000.serial: Linked as a consumer to 30380000.clock-controller
[    0.359782][    T1] platform 30880000.serial: Linked as a consumer to 303a0000.gpc
[    0.360024][    T1] platform 30890000.serial: Linked as a consumer to 30330000.pinctrl
[    0.360152][    T1] platform 30890000.serial: Linked as a consumer to 30380000.clock-controller
[    0.360223][    T1] platform 30890000.serial: Linked as a consumer to 303a0000.gpc
[    0.360474][    T1] platform 308c0000.sai: Linked as a consumer to 30330000.pinctrl
[    0.360591][    T1] platform 308c0000.sai: Linked as a consumer to 30380000.clock-controller
[    0.360662][    T1] platform 308c0000.sai: Linked as a consumer to 303a0000.gpc
[    0.360904][    T1] platform 30900000.crypto: Linked as a consumer to 30380000.clock-controller
[    0.360980][    T1] platform 30900000.crypto: Linked as a consumer to 303a0000.gpc
[    0.361263][    T1] platform 30a20000.i2c: Linked as a consumer to 30240000.gpio
[    0.361337][    T1] platform 30a20000.i2c: Linked as a consumer to 30330000.pinctrl
[    0.361448][    T1] platform 30a20000.i2c: Linked as a consumer to 30380000.clock-controller
[    0.361523][    T1] platform 30a20000.i2c: Linked as a consumer to 303a0000.gpc
[    0.361625][    T1] platform 30a20000.i2c: Linked as a sync state only consumer to 30200000.gpio
[    0.361880][    T1] platform 30a30000.i2c: Linked as a consumer to 30240000.gpio
[    0.361958][    T1] platform 30a30000.i2c: Linked as a consumer to 30330000.pinctrl
[    0.362062][    T1] platform 30a30000.i2c: Linked as a consumer to 30380000.clock-controller
[    0.362139][    T1] platform 30a30000.i2c: Linked as a consumer to 303a0000.gpc
[    0.362395][    T1] platform 30a40000.i2c: Linked as a consumer to 30240000.gpio
[    0.362474][    T1] platform 30a40000.i2c: Linked as a consumer to 30330000.pinctrl
[    0.362578][    T1] platform 30a40000.i2c: Linked as a consumer to 30380000.clock-controller
[    0.362654][    T1] platform 30a40000.i2c: Linked as a consumer to 303a0000.gpc
[    0.362911][    T1] platform 30aa0000.mailbox: Linked as a consumer to 30380000.clock-controller
[    0.362991][    T1] platform 30aa0000.mailbox: Linked as a consumer to 303a0000.gpc
[    0.363233][    T1] platform 30b40000.mmc: Linked as a consumer to 30330000.pinctrl
[    0.363345][    T1] platform 30b40000.mmc: Linked as a consumer to 30380000.clock-controller
[    0.363418][    T1] platform 30b40000.mmc: Linked as a consumer to 303a0000.gpc
[    0.363669][    T1] platform 30b50000.mmc: Linked as a consumer to 30210000.gpio
[    0.363740][    T1] platform 30b50000.mmc: Linked as a consumer to 30330000.pinctrl
[    0.363856][    T1] platform 30b50000.mmc: Linked as a consumer to 30380000.clock-controller
[    0.363933][    T1] platform 30b50000.mmc: Linked as a consumer to 303a0000.gpc
[    0.364193][    T1] platform 308c0000.sai: Linked as a consumer to 30bd0000.sdma
[    0.364264][    T1] platform 30830000.spi: Linked as a consumer to 30bd0000.sdma
[    0.364347][    T1] platform 30820000.spi: Linked as a consumer to 30bd0000.sdma
[    0.364424][    T1] platform 30bd0000.sdma: Linked as a consumer to 30380000.clock-controller
[    0.364497][    T1] platform 30bd0000.sdma: Linked as a consumer to 303a0000.gpc
[    0.364752][    T1] platform 30be0000.ethernet: Linked as a consumer to 30330000.pinctrl
[    0.364862][    T1] platform 30be0000.ethernet: Linked as a consumer to 30350000.efuse
[    0.364940][    T1] platform 30be0000.ethernet: Linked as a consumer to 30380000.clock-controller
[    0.365013][    T1] platform 30be0000.ethernet: Linked as a consumer to 303a0000.gpc
[    0.365261][    T1] platform 32700000.interconnect: Linked as a consumer to 30380000.clock-controller
[    0.365487][    T1] platform 32c00000.bus: Linked as a sync state only consumer to 30380000.clock-controller
[    0.365564][    T1] platform 32c00000.bus: Linked as a sync state only consumer to 303a0000.gpc
[    0.365795][    T1] platform 32e2d000.interrupt-controller: Linked as a consumer to 30380000.clock-controller
[    0.365877][    T1] platform 32e2d000.interrupt-controller: Linked as a consumer to 303a0000.gpc
[    0.366108][    T1] platform 38000000.gpu: Linked as a consumer to 30380000.clock-controller
[    0.366189][    T1] platform 38000000.gpu: Linked as a consumer to 303a0000.gpc
[    0.366417][    T1] platform 38100000.usb: Linked as a consumer to 303a0000.gpc
[    0.366511][    T1] platform 38100000.usb: Linked as a consumer to 30380000.clock-controller
[    0.366733][    T1] platform 38100000.usb: Linked as a consumer to 381f0040.usb-phy
[    0.366808][    T1] platform 381f0040.usb-phy: Linked as a consumer to 30380000.clock-controller
[    0.367025][    T1] platform 38200000.usb: Linked as a consumer to 303a0000.gpc
[    0.367124][    T1] platform 38200000.usb: Linked as a consumer to 30380000.clock-controller
[    0.367371][    T1] platform 38200000.usb: Linked as a consumer to 382f0040.usb-phy
[    0.367445][    T1] platform 382f0040.usb-phy: Linked as a consumer to 30380000.clock-controller
[    0.367664][    T1] platform 38300000.video-codec: Linked as a consumer to 30380000.clock-controller
[    0.367745][    T1] platform 38300000.video-codec: Linked as a consumer to 303a0000.gpc
[    0.367967][    T1] platform 38310000.video-codec: Linked as a consumer to 30380000.clock-controller
[    0.368048][    T1] platform 38310000.video-codec: Linked as a consumer to 303a0000.gpc
[    0.368308][    T1] platform 38310000.video-codec: Linked as a consumer to 38320000.blk-ctrl
[    0.368387][    T1] platform 38300000.video-codec: Linked as a consumer to 38320000.blk-ctrl
[    0.368462][    T1] platform 38320000.blk-ctrl: Linked as a consumer to 30380000.clock-controller
[    0.368542][    T1] platform 38320000.blk-ctrl: Linked as a consumer to 303a0000.gpc
[    0.368800][    T1] platform 33800000.pcie: Linked as a consumer to 30380000.clock-controller
[    0.368878][    T1] platform 33800000.pcie: Linked as a consumer to 30390000.reset-controller
[    0.368948][    T1] platform 33800000.pcie: Linked as a consumer to 303a0000.gpc
[    0.369210][    T1] platform 33c00000.pcie: Linked as a consumer to 30380000.clock-controller
[    0.369284][    T1] platform 33c00000.pcie: Linked as a consumer to 30390000.reset-controller
[    0.369361][    T1] platform 33c00000.pcie: Linked as a consumer to 303a0000.gpc
[    0.369721][    T1] platform 30b40000.mmc: Linked as a consumer to regulator-vcc1v8
[    0.369916][    T1] platform 30b40000.mmc: Linked as a consumer to regulator-vcc3v3
[    0.370041][    T1] regulator-vdd-arm Linked as a fwnode consumer to pinctrl@30330000
[    0.370081][    T1] regulator-vdd-arm Linked as a fwnode consumer to gpio@30200000
[    0.370179][    T1] platform regulator-vdd-arm: Linked as a consumer to 30200000.gpio
[    0.370254][    T1] platform regulator-vdd-arm: Linked as a consumer to 30330000.pinctrl
[    0.370410][    T1] beeper Linked as a fwnode consumer to pwm@30690000
[    0.370437][    T1] beeper Linked as a fwnode consumer to regulator-3v3
[    0.370519][    T1] platform beeper: Linked as a consumer to 30690000.pwm
[    0.370652][    T1] gpio-keys Linked as a fwnode consumer to pinctrl@30330000
[    0.370691][    T1] switch-1 Linked as a fwnode consumer to gpio@30200000
[    0.370729][    T1] switch-2 Linked as a fwnode consumer to gpio@30220000
[    0.370764][    T1] switch-3 Linked as a fwnode consumer to gpio@30200000
[    0.370853][    T1] platform gpio-keys: Linked as a consumer to 30330000.pinctrl
[    0.370957][    T1] platform gpio-keys: Linked as a sync state only consumer to 30200000.gpio
[    0.371032][    T1] platform gpio-keys: Linked as a sync state only consumer to 30220000.gpio
[    0.371162][    T1] gpio-leds Linked as a fwnode consumer to pinctrl@30330000
[    0.371192][    T1] led1 Linked as a fwnode consumer to gpio@30200000
[    0.371225][    T1] led2 Linked as a fwnode consumer to gpio@30220000
[    0.371255][    T1] led3 Linked as a fwnode consumer to gpio@30200000
[    0.371334][    T1] platform gpio-leds: Linked as a consumer to 30330000.pinctrl
[    0.371440][    T1] platform gpio-leds: Linked as a sync state only consumer to 30200000.gpio
[    0.371508][    T1] platform gpio-leds: Linked as a sync state only consumer to 30220000.gpio
[    0.371760][    T1] regulator-sn65dsi83-1v8 Linked as a fwnode consumer to gpio@23
[    0.371965][    T1] platform beeper: Linked as a consumer to regulator-3v3
[    0.372038][    T1] platform 33c00000.pcie: Linked as a consumer to regulator-3v3
[    0.372132][    T1] platform 33800000.pcie: Linked as a consumer to regulator-3v3
[    0.372210][    T1] platform 30be0000.ethernet: Linked as a consumer to regulator-3v3
[    0.372288][    T1] platform 30a30000.i2c: Linked as a sync state only consumer to regulator-3v3
[    0.372370][    T1] platform 30a20000.i2c: Linked as a sync state only consumer to regulator-3v3
[    0.372612][    T1] extcon-usbotg0 Linked as a fwnode consumer to pinctrl@30330000
[    0.372634][    T1] extcon-usbotg0 Linked as a fwnode consumer to gpio@30200000
[    0.372721][    T1] platform 38100000.usb: Linked as a consumer to extcon-usbotg0
[    0.372794][    T1] platform extcon-usbotg0: Linked as a consumer to 30200000.gpio
[    0.372870][    T1] platform extcon-usbotg0: Linked as a consumer to 30330000.pinctrl
[    0.373026][    T1] regulator-otg-vbus Linked as a fwnode consumer to pinctrl@30330000
[    0.373058][    T1] regulator-otg-vbus Linked as a fwnode consumer to gpio@30200000
[    0.373144][    T1] platform 381f0040.usb-phy: Linked as a consumer to regulator-otg-vbus
[    0.373223][    T1] platform regulator-otg-vbus: Linked as a consumer to 30200000.gpio
[    0.373303][    T1] platform regulator-otg-vbus: Linked as a consumer to 30330000.pinctrl
[    0.373468][    T1] regulator-vmmc Linked as a fwnode consumer to gpio@30210000
[    0.373557][    T1] platform 30b50000.mmc: Linked as a consumer to regulator-vmmc
[    0.373629][    T1] platform regulator-vmmc: Linked as a consumer to 30210000.gpio
[    0.374218][    T1] KASLR disabled due to lack of seed
[    0.388702][    T1] HugeTLB: registered 1.00 GiB page size, pre-allocated 0 pages
[    0.393390][    T1] HugeTLB: 16380 KiB vmemmap can be freed for a 1.00 GiB page
[    0.400687][    T1] HugeTLB: registered 32.0 MiB page size, pre-allocated 0 pages
[    0.408180][    T1] HugeTLB: 508 KiB vmemmap can be freed for a 32.0 MiB page
[    0.415333][    T1] HugeTLB: registered 2.00 MiB page size, pre-allocated 0 pages
[    0.422830][    T1] HugeTLB: 28 KiB vmemmap can be freed for a 2.00 MiB page
[    0.429896][    T1] HugeTLB: registered 64.0 KiB page size, pre-allocated 0 pages
[    0.437392][    T1] HugeTLB: 0 KiB vmemmap can be freed for a 64.0 KiB page
[    0.445115][    T1] cryptd: max_cpu_qlen set to 1000
[    0.452708][    T1] iommu: Default domain type: Translated 
[    0.455480][    T1] iommu: DMA domain TLB invalidation policy: strict mode 
[    0.462785][    T1] SCSI subsystem initialized
[    0.467027][    T1] libata version 3.00 loaded.
[    0.467296][    T1] usbcore: registered new interface driver usbfs
[    0.473114][    T1] usbcore: registered new interface driver hub
[    0.479109][    T1] usbcore: registered new device driver usb
[    0.485493][    T1] mc: Linux media interface: v0.10
[    0.489841][    T1] videodev: Linux video capture interface: v2.00
[    0.496022][    T1] pps_core: LinuxPPS API ver. 1 registered
[    0.501661][    T1] pps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo Giometti <[e-mail]>
[    0.511529][    T1] PTP clock support registered
[    0.516295][    T1] EDAC MC: Ver: 3.0.0
[    0.520929][    T1] FPGA manager framework
[    0.524168][    T1] Advanced Linux Sound Architecture Driver Initialized.
[    0.531982][    T1] vgaarb: loaded
[    0.534640][    T1] clocksource: Switched to clocksource arch_sys_counter
[    0.541330][    T1] VFS: Disk quotas dquot_6.6.0
[    0.545754][    T1] VFS: Dquot-cache hash table entries: 512 (order 0, 4096 bytes)
[    0.562786][    T1] NET: Registered PF_INET protocol family
[    0.565777][    T1] IP idents hash table entries: 65536 (order: 7, 524288 bytes, linear)
[    0.577693][    T1] tcp_listen_portaddr_hash hash table entries: 2048 (order: 3, 32768 bytes, linear)
[    0.584158][    T1] Table-perturb hash table entries: 65536 (order: 6, 262144 bytes, linear)
[    0.592571][    T1] TCP established hash table entries: 32768 (order: 6, 262144 bytes, linear)
[    0.601494][    T1] TCP bind hash table entries: 32768 (order: 7, 524288 bytes, linear)
[    0.609827][    T1] TCP: Hash tables configured (established 32768 bind 32768)
[    0.616560][    T1] UDP hash table entries: 2048 (order: 4, 65536 bytes, linear)
[    0.623972][    T1] UDP-Lite hash table entries: 2048 (order: 4, 65536 bytes, linear)
[    0.631945][    T1] NET: Registered PF_UNIX/PF_LOCAL protocol family
[    0.638470][    T1] RPC: Registered named UNIX socket transport module.
[    0.644711][    T1] RPC: Registered udp transport module.
[    0.650116][    T1] RPC: Registered tcp transport module.
[    0.655516][    T1] RPC: Registered tcp NFSv4.1 backchannel transport module.
[    0.662672][    T1] PCI: CLS 0 bytes, default 64
[    0.668140][    T1] hw perfevents: enabled with armv8_cortex_a53 PMU driver, 7 counters available
[    0.678299][    T1] Initialise system trusted keyrings
[    0.681494][    T1] workingset: timestamp_bits=42 max_order=20 bucket_order=0
[    0.697669][    T1] squashfs: version 4.0 (2009/01/31) Phillip Lougher
[    0.702176][    T1] NFS: Registering the id_resolver key type
[    0.707163][    T1] Key type id_resolver registered
[    0.712008][    T1] Key type id_legacy registered
[    0.716812][    T1] nfs4filelayout_init: NFSv4 File Layout Driver Registering...
[    0.724130][    T1] nfs4flexfilelayout_init: NFSv4 Flexfile Layout Driver Registering...
[    0.787889][    T1] Key type asymmetric registered
[    0.789832][    T1] Asymmetric key parser 'x509' registered
[    0.795474][    T1] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 243)
[    0.803537][    T1] io scheduler mq-deadline registered
[    0.808765][    T1] io scheduler kyber registered
[    0.820609][    T1] imx-pgc imx-pgc-domain.0: imx_pgc_domain_probe: Probe succeeded
[    0.825861][    T1] imx-pgc imx-pgc-domain.2: imx_pgc_domain_probe: Probe succeeded
[    0.833300][    T1] imx-pgc imx-pgc-domain.3: imx_pgc_domain_probe: Probe succeeded
[    0.840957][    T1] imx-pgc imx-pgc-domain.4: imx_pgc_domain_probe: Probe succeeded
[    0.849079][    T1] imx-pgc imx-pgc-domain.7: imx_pgc_domain_probe: Probe succeeded
[    0.856313][    T1] imx-pgc imx-pgc-domain.8: imx_pgc_domain_probe: Probe succeeded
[    0.863985][    T1] imx-pgc imx-pgc-domain.9: imx_pgc_domain_probe: Probe succeeded
[    0.871658][    T1] imx-pgc imx-pgc-domain.10: imx_pgc_domain_probe: Probe succeeded
[    0.879282][    T1] imx-gpcv2 303a0000.gpc: imx_gpcv2_probe: Probe succeeded
[    0.886886][    T1] SoC: i.MX8MQ revision 2.1
[    0.896040][    T1] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
[    0.916005][    T1] igbvf: Intel(R) Gigabit Virtual Function Network Driver
[    0.920152][    T1] igbvf: Copyright (c) 2009 - 2012 Intel Corporation.
[    0.927211][    T1] VFIO - User Level meta-driver version: 0.3
[    0.934574][    T1] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
[    0.939877][    T1] ehci-pci: EHCI PCI platform driver
[    0.945038][    T1] ehci-platform: EHCI generic platform driver
[    0.952771][    T1] i2c_dev: i2c /dev entries driver
[    0.958624][    T1] sdhci: Secure Digital Host Controller Interface driver
[    0.962791][    T1] sdhci: Copyright(c) Pierre Ossman
[    0.968202][    T1] Synopsys Designware Multimedia Card Interface Driver
[    0.975227][    T1] sdhci-pltfm: SDHCI platform and OF driver helper
[    0.983039][    T1] ledtrig-cpu: registered to indicate activity on CPUs
[    0.988797][    T1] hid: raw HID events driver (C) Jiri Kosina
[    0.994056][    T1] usbcore: registered new interface driver usbhid
[    0.999766][    T1] usbhid: USB HID core driver
[    1.007142][    T1]  cs_system_cfg: CoreSight Configuration manager initialised
[    1.017973][    T1] NET: Registered PF_PACKET protocol family
[    1.021006][    T1] Key type dns_resolver registered
[    1.026254][    T1] registered taskstats version 1
[    1.030692][    T1] Loading compiled-in X.509 certificates
[    1.072731][    T8] imx8m-blk-ctrl 38320000.blk-ctrl: error -ENODEV: failed to attach power domain "bus"

Tony Lindgren July 12, 2022, 7:12 a.m. UTC | #30

* Tony Lindgren <[e-mail]> [220701 16:00]:
> Also, looks like both with the initcall change for prm, and the patch
> below, there seems to be also another problem where my test devices no
> longer properly idle somehow compared to reverting the your two patches
> in next.

Sorry looks like was a wrong conclusion. While trying to track down this
issue, I cannot reproduce it. So I don't see issues idling with either
the initcall change or your test patch.

Not sure what caused my earlier tests to fail though. Maybe a config
change to enable more debugging, or possibly some kind of warm reset vs
cold reset type issue.

Regards,

Tony

Saravana Kannan July 13, 2022, 12:45 a.m. UTC | #31

On Wed, Jul 6, 2022 at 6:02 AM Alexander Stein
<[e-mail]> wrote:
>

Thanks for testing all my patches and helping me debug this.

Btw, can you try to keep the subject the same please? Looks like
somewhere in your path [EXT] is added sometimes. lore.kernel.org keeps
the thread together, but my email client (gmail) gets confused.

> Am Dienstag, 5. Juli 2022, 03:24:33 CEST schrieb Saravana Kannan:
> > On Mon, Jul 4, 2022 at 12:07 AM Alexander Stein
> >
> > <[e-mail]> wrote:
> > > Am Freitag, 1. Juli 2022, 09:02:22 CEST schrieb Saravana Kannan:
> > > > On Thu, Jun 30, 2022 at 11:02 PM Alexander Stein
> > > >
> > > > <[e-mail]> wrote:
> > > > > Hi Saravana,
> > > > >
> > > > > Am Freitag, 1. Juli 2022, 02:37:14 CEST schrieb Saravana Kannan:
> > > > > > On Thu, Jun 23, 2022 at 5:08 AM Alexander Stein
> > > > > >
> > > > > > <[e-mail]> wrote:
> > > > > > > Hi,
> > > > > > >
> > > > > > > Am Dienstag, 21. Juni 2022, 09:28:43 CEST schrieb Tony Lindgren:
> > > > > > > > Hi,
> > > > > > > >
> > > > > > > > * Saravana Kannan <[e-mail]> [700101 02:00]:
> > > > > > > > > Now that fw_devlink=on by default and fw_devlink supports
> > > > > > > > > "power-domains" property, the execution will never get to the
> > > > > > > > > point
> > > > > > > > > where driver_deferred_probe_check_state() is called before the
> > > > > > > > > supplier
> > > > > > > > > has probed successfully or before deferred probe timeout has
> > > > > > > > > expired.
> > > > > > > > >
> > > > > > > > > So, delete the call and replace it with -ENODEV.
> > > > > > > >
> > > > > > > > Looks like this causes omaps to not boot in Linux next. With
> > > > > > > > this
> > > > > > > > simple-pm-bus fails to probe initially as the power-domain is
> > > > > > > > not
> > > > > > > > yet available. On platform_probe() genpd_get_from_provider()
> > > > > > > > returns
> > > > > > > > -ENOENT.
> > > > > > > >
> > > > > > > > Seems like other stuff is potentially broken too, any ideas on
> > > > > > > > how to fix this?
> > > > > > >
> > > > > > > I think I'm hit by this as well, although I do not get a lockup.
> > > > > > > In my case I'm using
> > > > > > > arch/arm64/boot/dts/freescale/imx8mq-tqma8mq-mba8mx.dts and
> > > > > > > probing of
> > > > > > > 38320000.blk-ctrl fails as the power-domain is not (yet) registed.
> > > > > >
> > > > > > Ok, took a look.
> > > > > >
> > > > > > The problem is that there are two drivers for the same device and
> > > > > > they
> > > > > > both initialize this device.
> > > > > >
> > > > > >     gpc: gpc@303a0000 {
> > > > > >
> > > > > >         compatible = "fsl,imx8mq-gpc";
> > > > > >
> > > > > >     }
> > > > > >
> > > > > > $ git grep -l "fsl,imx7d-gpc" -- drivers/
> > > > > > drivers/irqchip/irq-imx-gpcv2.c
> > > > > > drivers/soc/imx/gpcv2.c
> > > > > >
> > > > > > IMHO, this is a bad/broken design.
> > > > > >
> > > > > > So what's happening is that fw_devlink will block the probe of
> > > > > > 38320000.blk-ctrl until 303a0000.gpc is initialized. And it stops
> > > > > > blocking the probe of 38320000.blk-ctrl as soon as the first driver
> > > > > > initializes the device. In this case, it's the irqchip driver.
> > > > > >
> > > > > > I'd recommend combining these drivers into one. Something like the
> > > > > > patch I'm attaching (sorry for the attachment, copy-paste is
> > > > > > mangling
> > > > > > the tabs). Can you give it a shot please?
> > > > >
> > > > > I tried this patch and it delayed the driver initialization (those of
> > > > > UART
> > > > > as
> > > >
> > > > > well BTW). Unfortunately the driver fails the same way:
> > > > Thanks for testing the patch!
> > > >
> > > > > > [    1.125253] imx8m-blk-ctrl 38320000.blk-ctrl: error -ENODEV:
> > > > > > failed
> > > > > > to
> > > > >
> > > > > attach power domain "bus"
> > > > >
> > > > > More than that it even introduced some more errors:
> > > > > > [    0.008160] irq: no irq domain found for gpc@303a0000 !
> > > >
> > > > So the idea behind my change was that as long as the irqchip isn't the
> > > > root of the irqdomain (might be using the terms incorrectly) like the
> > > > gic, you can make it a platform driver. And I was trying to hack up a
> > > > patch that's the equivalent of platform_irqchip_probe() (which just
> > > > ends up eventually calling the callback you use in IRQCHIP_DECLARE().
> > > > I probably made some mistake in the quick hack that I'm sure if
> > > > fixable.
> > > >
> > > > > > [    0.013251] Failed to map interrupt for
> > > > > > /soc@0/bus@30400000/timer@306a0000
> > > >
> > > > However, this timer driver also uses TIMER_OF_DECLARE() which can't
> > > > handle failure to get the IRQ (because it's can't -EPROBE_DEFER). So,
> > > > this means, the timer driver inturn needs to be converted to a
> > > > platform driver if it's supposed to work with the IRQCHIP_DECLARE()
> > > > being converted to a platform driver.
> > > >
> > > > But that's a can of worms not worth opening. But then I remembered
> > > > this simpler workaround will work and it is pretty much a variant of
> > > > the workaround that's already in the gpc's irqchip driver to allow two
> > > > drivers to probe the same device (people really should stop doing
> > > > that).
> > > >
> > > > Can you drop my previous hack patch and try this instead please? I'm
> > > > 99% sure this will work.
> > > >
> > > > diff --git a/drivers/irqchip/irq-imx-gpcv2.c
> > > > b/drivers/irqchip/irq-imx-gpcv2.c index b9c22f764b4d..8a0e82067924
> > > > 100644
> > > > --- a/drivers/irqchip/irq-imx-gpcv2.c
> > > > +++ b/drivers/irqchip/irq-imx-gpcv2.c
> > > > @@ -283,6 +283,7 @@ static int __init imx_gpcv2_irqchip_init(struct
> > > > device_node *node,
> > > >
> > > >          * later the GPC power domain driver will not be skipped.
> > > >          */
> > > >
> > > >         of_node_clear_flag(node, OF_POPULATED);
> > > >
> > > > +       fwnode_dev_initialized(domain->fwnode, false);
> > > >
> > > >         return 0;
> > > >
> > > >  }
> > >
> > > Just to be sure here, I tried this patch on top of next-20220701 but
> > > unfortunately this doesn't fix the original problem either. The timer
> > > errors are gone though.
> >
> > To clarify, you had the timer issue only with my "combine drivers" patch,
> > right?
>
> That's correct.
>
> > > The probe of imx8m-blk-ctrl got slightly delayed (from 0.74 to 0.90s
> > > printk
> > > time) but results in the identical error message.
> >
> > My guess is that the probe attempt of blk-ctrl is delayed now till gpc
> > probes (because of the device links getting created with the
> > fwnode_dev_initialized() fix), but by the time gpc probe finishes, the
> > power domains aren't registered yet because of the additional level of
> > device addition and probing.
> >
> > Can you try the attached patch please?
>
> Sure, it needed some small fixes though. But the error still is present.
>
> > And if that doesn't fix the issues, then enable the debug logs in the
> > following functions please and share the logs from boot till the
> > failure? If you can enable CONFIG_PRINTK_CALLER, that'd help too.
> > device_link_add()
> > fwnode_link_add()
> > fw_devlink_relax_cycle()
>
> I switched fw_devlink_relax_cycle() for fw_devlink_relax_link() as the former
> has no debug output here.
>
> For the record I added the following line to my kernel command line:
> > dyndbg="func device_link_add +p; func fwnode_link_add +p; func
> fw_devlink_relax_link +p"
>
> I attached the dmesg until the probe error to this mail. But I noticed the
> following lines which seem interesting:
> > [    1.466620][    T8] imx-pgc imx-pgc-domain.5: Linked as a consumer to
> > regulator.8
> > [    1.466743][    T8] imx-pgc imx-pgc-domain.5: imx_pgc_domain_probe: Probe
> succeeded
> > [    1.474733][    T8] imx-pgc imx-pgc-domain.6: Linked as a consumer to
> regulator.9
> > [    1.474774][    T8] imx-pgc imx-pgc-domain.6: imx_pgc_domain_probe: Probe
> succeeded

I'm guessing this happens after the probe error.

Ok, I looked at the dmesg logs and this pretty much confirms my
thought on why the probe ordering wasn't maintained.

The power domains lack a compatible property, so the blk-ctrl is
linked as a consumer of the gpc instead:
[    0.343905][    T1] blk-ctrl@38320000 Linked as a fwnode consumer
to gpc@303a0000
[    0.343943][    T1] blk-ctrl@38320000 Linked as a fwnode consumer
to clock-controller@30380000
This ^^ is the device tree parsing figuring out the dependencies
between the DT nodes.

[    0.368462][    T1] platform 38320000.blk-ctrl: Linked as a
consumer to 30380000.clock-controller
[    0.368542][    T1] platform 38320000.blk-ctrl: Linked as a
consumer to 303a0000.gpc
This ^^ is converting the DT node dependencies into device links.

So, the only real options are:
1. Fix DT and add a compatible string to the DT nodes.
2. Move the initcall level of the regulator driver so the powerdomain
probe doesn't get deferred. Not ideal that we are playing initcall
chicken to handle the feature meant to remove the need for initcall
chicken. But I see these "device, but won't have a compatible
property" as exceptions and feel it's okay to have to play with
initcall levels to handle those.
3. Provide a helper function that driver that do this (creating
devices for child DT nodes without compatible property) can use to
move/copy their consumer device links to the child devices they add.
And then fix up the gpc driver so that it copies the gpc -- blk-ctrl
device link to the proper power domain.
4. I have another idea for how I could fix that at a driver core
level, but I'm not sure it'll work yet and its definitely not
something I want to try and get in for 5.19 -- too late for that IMHO.

Want to give (2) a shot so that I can still try to keep the cleanup
series that caused this problem (that's the long term goal) while I
give (3) and (4) a shot for 5.20?

> regulator.8 and regulator.9 is the power sequencer, attached on I2C. This also
> makes perfectly sense if you look at [1]ff. These power domains are supplied
> by specific power supply rails. Several, if not all, imx8mq boards have this
> kind of setting.

Yeah, makes sense in terms of what's going on.

-Saravana

>
> > Btw, part of the reason I'm trying to make sure we fix it the right
> > way is that when we try to enable async boot by default, we don't run
> > into issues.
>
> Sounds resonable.
>
> Best regards,
> Alexander
>
> [1] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/
> arch/arm64/boot/dts/freescale/imx8mq-tqma8mq.dtsi#n84

Saravana Kannan July 13, 2022, 12:49 a.m. UTC | #32

On Tue, Jul 12, 2022 at 12:12 AM Tony Lindgren <[e-mail]> wrote:
>
> * Tony Lindgren <[e-mail]> [220701 16:00]:
> > Also, looks like both with the initcall change for prm, and the patch
> > below, there seems to be also another problem where my test devices no
> > longer properly idle somehow compared to reverting the your two patches
> > in next.
>
> Sorry looks like was a wrong conclusion. While trying to track down this
> issue, I cannot reproduce it. So I don't see issues idling with either
> the initcall change or your test patch.
>
> Not sure what caused my earlier tests to fail though. Maybe a config
> change to enable more debugging, or possibly some kind of warm reset vs
> cold reset type issue.

Thanks for getting back to me about the false alarm.

OK, so it looks like my patch to drivers/of/property.c fixed the issue
for you. In that case, let me test that a bit more thoroughly on my
end to make sure it's not breaking any existing functionality. And if
it's not breaking, I'll land that in the kernel eventually. Might be a
bit too late for 5.19. I'm considering temporarily reverting my series
depending on how the rest of the issues from my series go.

-Saravana

Tony Lindgren July 13, 2022, 8:06 a.m. UTC | #33

* Saravana Kannan <[e-mail]> [220713 00:44]:
> On Tue, Jul 12, 2022 at 12:12 AM Tony Lindgren <[e-mail]> wrote:
> >
> > * Tony Lindgren <[e-mail]> [220701 16:00]:
> > > Also, looks like both with the initcall change for prm, and the patch
> > > below, there seems to be also another problem where my test devices no
> > > longer properly idle somehow compared to reverting the your two patches
> > > in next.
> >
> > Sorry looks like was a wrong conclusion. While trying to track down this
> > issue, I cannot reproduce it. So I don't see issues idling with either
> > the initcall change or your test patch.
> >
> > Not sure what caused my earlier tests to fail though. Maybe a config
> > change to enable more debugging, or possibly some kind of warm reset vs
> > cold reset type issue.
> 
> Thanks for getting back to me about the false alarm.

FYI I'm pretty sure I had also some pending sdhci related patches applied
while testing causing extra issues.

> OK, so it looks like my patch to drivers/of/property.c fixed the issue
> for you. In that case, let me test that a bit more thoroughly on my
> end to make sure it's not breaking any existing functionality. And if
> it's not breaking, I'll land that in the kernel eventually. Might be a
> bit too late for 5.19. I'm considering temporarily reverting my series
> depending on how the rest of the issues from my series go.

OK. Seems the series is otherwise working and in case of issues, partial
revert should be enough in the worst case. But yeah, probably some more
testing is needed.

Regards,

Tony

Alexander Stein July 14, 2022, 6:41 a.m. UTC | #34

Am Mittwoch, 13. Juli 2022, 02:45:06 CEST schrieb Saravana Kannan:
> On Wed, Jul 6, 2022 at 6:02 AM Alexander Stein
> <[e-mail]> wrote:
> 
> 
> Thanks for testing all my patches and helping me debug this.
> 
> Btw, can you try to keep the subject the same please? Looks like
> somewhere in your path [EXT] is added sometimes. lore.kernel.org keeps
> the thread together, but my email client (gmail) gets confused.

Sorry about that. Unfortunately [EXT] is inserted automatically and it is 
tedious and error-prone to remove it manually...

> > Am Dienstag, 5. Juli 2022, 03:24:33 CEST schrieb Saravana Kannan:
> > > On Mon, Jul 4, 2022 at 12:07 AM Alexander Stein
> > > 
> > > <[e-mail]> wrote:
> > > > Am Freitag, 1. Juli 2022, 09:02:22 CEST schrieb Saravana Kannan:
> > > > > On Thu, Jun 30, 2022 at 11:02 PM Alexander Stein
> > > > > 
> > > > > <[e-mail]> wrote:
> > > > > > Hi Saravana,
> > > > > > 
> > > > > > Am Freitag, 1. Juli 2022, 02:37:14 CEST schrieb Saravana Kannan:
> > > > > > > On Thu, Jun 23, 2022 at 5:08 AM Alexander Stein
> > > > > > > 
> > > > > > > <[e-mail]> wrote:
> > > > > > > > Hi,
> > > > > > > > 
> > > > > > > > Am Dienstag, 21. Juni 2022, 09:28:43 CEST schrieb Tony 
Lindgren:
> > > > > > > > > Hi,
> > > > > > > > > 
> > > > > > > > > * Saravana Kannan <[e-mail]> [700101 02:00]:
> > > > > > > > > > Now that fw_devlink=on by default and fw_devlink supports
> > > > > > > > > > "power-domains" property, the execution will never get to
> > > > > > > > > > the
> > > > > > > > > > point
> > > > > > > > > > where driver_deferred_probe_check_state() is called before
> > > > > > > > > > the
> > > > > > > > > > supplier
> > > > > > > > > > has probed successfully or before deferred probe timeout
> > > > > > > > > > has
> > > > > > > > > > expired.
> > > > > > > > > > 
> > > > > > > > > > So, delete the call and replace it with -ENODEV.
> > > > > > > > > 
> > > > > > > > > Looks like this causes omaps to not boot in Linux next. With
> > > > > > > > > this
> > > > > > > > > simple-pm-bus fails to probe initially as the power-domain
> > > > > > > > > is
> > > > > > > > > not
> > > > > > > > > yet available. On platform_probe() genpd_get_from_provider()
> > > > > > > > > returns
> > > > > > > > > -ENOENT.
> > > > > > > > > 
> > > > > > > > > Seems like other stuff is potentially broken too, any ideas
> > > > > > > > > on
> > > > > > > > > how to fix this?
> > > > > > > > 
> > > > > > > > I think I'm hit by this as well, although I do not get a
> > > > > > > > lockup.
> > > > > > > > In my case I'm using
> > > > > > > > arch/arm64/boot/dts/freescale/imx8mq-tqma8mq-mba8mx.dts and
> > > > > > > > probing of
> > > > > > > > 38320000.blk-ctrl fails as the power-domain is not (yet)
> > > > > > > > registed.
> > > > > > > 
> > > > > > > Ok, took a look.
> > > > > > > 
> > > > > > > The problem is that there are two drivers for the same device
> > > > > > > and
> > > > > > > they
> > > > > > > both initialize this device.
> > > > > > > 
> > > > > > >     gpc: gpc@303a0000 {
> > > > > > >     
> > > > > > >         compatible = "fsl,imx8mq-gpc";
> > > > > > >     
> > > > > > >     }
> > > > > > > 
> > > > > > > $ git grep -l "fsl,imx7d-gpc" -- drivers/
> > > > > > > drivers/irqchip/irq-imx-gpcv2.c
> > > > > > > drivers/soc/imx/gpcv2.c
> > > > > > > 
> > > > > > > IMHO, this is a bad/broken design.
> > > > > > > 
> > > > > > > So what's happening is that fw_devlink will block the probe of
> > > > > > > 38320000.blk-ctrl until 303a0000.gpc is initialized. And it
> > > > > > > stops
> > > > > > > blocking the probe of 38320000.blk-ctrl as soon as the first
> > > > > > > driver
> > > > > > > initializes the device. In this case, it's the irqchip driver.
> > > > > > > 
> > > > > > > I'd recommend combining these drivers into one. Something like
> > > > > > > the
> > > > > > > patch I'm attaching (sorry for the attachment, copy-paste is
> > > > > > > mangling
> > > > > > > the tabs). Can you give it a shot please?
> > > > > > 
> > > > > > I tried this patch and it delayed the driver initialization (those
> > > > > > of
> > > > > > UART
> > > > > > as
> > > > > 
> > > > > > well BTW). Unfortunately the driver fails the same way:
> > > > > Thanks for testing the patch!
> > > > > 
> > > > > > > [    1.125253] imx8m-blk-ctrl 38320000.blk-ctrl: error -ENODEV:
> > > > > > > failed
> > > > > > > to
> > > > > > 
> > > > > > attach power domain "bus"
> > > > > > 
> > > > > > More than that it even introduced some more errors:
> > > > > > > [    0.008160] irq: no irq domain found for gpc@303a0000 !
> > > > > 
> > > > > So the idea behind my change was that as long as the irqchip isn't
> > > > > the
> > > > > root of the irqdomain (might be using the terms incorrectly) like
> > > > > the
> > > > > gic, you can make it a platform driver. And I was trying to hack up
> > > > > a
> > > > > patch that's the equivalent of platform_irqchip_probe() (which just
> > > > > ends up eventually calling the callback you use in
> > > > > IRQCHIP_DECLARE().
> > > > > I probably made some mistake in the quick hack that I'm sure if
> > > > > fixable.
> > > > > 
> > > > > > > [    0.013251] Failed to map interrupt for
> > > > > > > /soc@0/bus@30400000/timer@306a0000
> > > > > 
> > > > > However, this timer driver also uses TIMER_OF_DECLARE() which can't
> > > > > handle failure to get the IRQ (because it's can't -EPROBE_DEFER).
> > > > > So,
> > > > > this means, the timer driver inturn needs to be converted to a
> > > > > platform driver if it's supposed to work with the IRQCHIP_DECLARE()
> > > > > being converted to a platform driver.
> > > > > 
> > > > > But that's a can of worms not worth opening. But then I remembered
> > > > > this simpler workaround will work and it is pretty much a variant of
> > > > > the workaround that's already in the gpc's irqchip driver to allow
> > > > > two
> > > > > drivers to probe the same device (people really should stop doing
> > > > > that).
> > > > > 
> > > > > Can you drop my previous hack patch and try this instead please? I'm
> > > > > 99% sure this will work.
> > > > > 
> > > > > diff --git a/drivers/irqchip/irq-imx-gpcv2.c
> > > > > b/drivers/irqchip/irq-imx-gpcv2.c index b9c22f764b4d..8a0e82067924
> > > > > 100644
> > > > > --- a/drivers/irqchip/irq-imx-gpcv2.c
> > > > > +++ b/drivers/irqchip/irq-imx-gpcv2.c
> > > > > @@ -283,6 +283,7 @@ static int __init imx_gpcv2_irqchip_init(struct
> > > > > device_node *node,
> > > > > 
> > > > >          * later the GPC power domain driver will not be skipped.
> > > > >          */
> > > > >         
> > > > >         of_node_clear_flag(node, OF_POPULATED);
> > > > > 
> > > > > +       fwnode_dev_initialized(domain->fwnode, false);
> > > > > 
> > > > >         return 0;
> > > > >  
> > > > >  }
> > > > 
> > > > Just to be sure here, I tried this patch on top of next-20220701 but
> > > > unfortunately this doesn't fix the original problem either. The timer
> > > > errors are gone though.
> > > 
> > > To clarify, you had the timer issue only with my "combine drivers"
> > > patch,
> > > right?
> > 
> > That's correct.
> > 
> > > > The probe of imx8m-blk-ctrl got slightly delayed (from 0.74 to 0.90s
> > > > printk
> > > > time) but results in the identical error message.
> > > 
> > > My guess is that the probe attempt of blk-ctrl is delayed now till gpc
> > > probes (because of the device links getting created with the
> > > fwnode_dev_initialized() fix), but by the time gpc probe finishes, the
> > > power domains aren't registered yet because of the additional level of
> > > device addition and probing.
> > > 
> > > Can you try the attached patch please?
> > 
> > Sure, it needed some small fixes though. But the error still is present.
> > 
> > > And if that doesn't fix the issues, then enable the debug logs in the
> > > following functions please and share the logs from boot till the
> > > failure? If you can enable CONFIG_PRINTK_CALLER, that'd help too.
> > > device_link_add()
> > > fwnode_link_add()
> > > fw_devlink_relax_cycle()
> > 
> > I switched fw_devlink_relax_cycle() for fw_devlink_relax_link() as the
> > former has no debug output here.
> > 
> > For the record I added the following line to my kernel command line:
> > > dyndbg="func device_link_add +p; func fwnode_link_add +p; func
> > 
> > fw_devlink_relax_link +p"
> > 
> > I attached the dmesg until the probe error to this mail. But I noticed the
> > 
> > following lines which seem interesting:
> > > [    1.466620][    T8] imx-pgc imx-pgc-domain.5: Linked as a consumer to
> > > regulator.8
> > > [    1.466743][    T8] imx-pgc imx-pgc-domain.5: imx_pgc_domain_probe:
> > > Probe> 
> > succeeded
> > 
> > > [    1.474733][    T8] imx-pgc imx-pgc-domain.6: Linked as a consumer to
> > 
> > regulator.9
> > 
> > > [    1.474774][    T8] imx-pgc imx-pgc-domain.6: imx_pgc_domain_probe:
> > > Probe> 
> > succeeded
> 
> I'm guessing this happens after the probe error.
> 
> Ok, I looked at the dmesg logs and this pretty much confirms my
> thought on why the probe ordering wasn't maintained.
> 
> The power domains lack a compatible property, so the blk-ctrl is
> linked as a consumer of the gpc instead:
> [    0.343905][    T1] blk-ctrl@38320000 Linked as a fwnode consumer
> to gpc@303a0000
> [    0.343943][    T1] blk-ctrl@38320000 Linked as a fwnode consumer
> to clock-controller@30380000
> This ^^ is the device tree parsing figuring out the dependencies
> between the DT nodes.
> 
> [    0.368462][    T1] platform 38320000.blk-ctrl: Linked as a
> consumer to 30380000.clock-controller
> [    0.368542][    T1] platform 38320000.blk-ctrl: Linked as a
> consumer to 303a0000.gpc
> This ^^ is converting the DT node dependencies into device links.
> 
> So, the only real options are:
> 1. Fix DT and add a compatible string to the DT nodes.
> 2. Move the initcall level of the regulator driver so the powerdomain
> probe doesn't get deferred. Not ideal that we are playing initcall
> chicken to handle the feature meant to remove the need for initcall
> chicken. But I see these "device, but won't have a compatible
> property" as exceptions and feel it's okay to have to play with
> initcall levels to handle those.
> 3. Provide a helper function that driver that do this (creating
> devices for child DT nodes without compatible property) can use to
> move/copy their consumer device links to the child devices they add.
> And then fix up the gpc driver so that it copies the gpc -- blk-ctrl
> device link to the proper power domain.
> 4. I have another idea for how I could fix that at a driver core
> level, but I'm not sure it'll work yet and its definitely not
> something I want to try and get in for 5.19 -- too late for that IMHO.
> 
> Want to give (2) a shot so that I can still try to keep the cleanup
> series that caused this problem (that's the long term goal) while I
> give (3) and (4) a shot for 5.20?

Sure, I can give (2) a shot. Which initcall needs to be modified? You have a 
diff snippet?
BTW: this potentially affects all imx8m and imx7d as they have the same gpc 
binding.

Can't say much about (1). I added Lucas Stach to recipients, he did a lot on 
this gpc driver.
@Lucas: Do you have some input why the gpc power domains do not have a 
compatible? Is it reasonable to add them?

Best regards,
Alexander

> > regulator.8 and regulator.9 is the power sequencer, attached on I2C. This
> > also makes perfectly sense if you look at [1]ff. These power domains are
> > supplied by specific power supply rails. Several, if not all, imx8mq
> > boards have this kind of setting.
> 
> Yeah, makes sense in terms of what's going on.
> 
> -Saravana
> 
> > > Btw, part of the reason I'm trying to make sure we fix it the right
> > > way is that when we try to enable async boot by default, we don't run
> > > into issues.
> > 
> > Sounds resonable.
> > 
> > Best regards,
> > Alexander
> > 
> > [1]
> > https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/
> > arch/arm64/boot/dts/freescale/imx8mq-tqma8mq.dtsi#n84

Saravana Kannan July 15, 2022, 10:08 p.m. UTC | #35

On Wed, Jul 13, 2022 at 11:41 PM Alexander Stein
<[e-mail]> wrote:
>
> Am Mittwoch, 13. Juli 2022, 02:45:06 CEST schrieb Saravana Kannan:
> > On Wed, Jul 6, 2022 at 6:02 AM Alexander Stein
> > <[e-mail]> wrote:
> >
> >
> > Thanks for testing all my patches and helping me debug this.
> >
> > Btw, can you try to keep the subject the same please? Looks like
> > somewhere in your path [EXT] is added sometimes. lore.kernel.org keeps
> > the thread together, but my email client (gmail) gets confused.
>
> Sorry about that. Unfortunately [EXT] is inserted automatically and it is
> tedious and error-prone to remove it manually...
>
> > > Am Dienstag, 5. Juli 2022, 03:24:33 CEST schrieb Saravana Kannan:
> > > > On Mon, Jul 4, 2022 at 12:07 AM Alexander Stein
> > > >
> > > > <[e-mail]> wrote:
> > > > > Am Freitag, 1. Juli 2022, 09:02:22 CEST schrieb Saravana Kannan:
> > > > > > On Thu, Jun 30, 2022 at 11:02 PM Alexander Stein
> > > > > >
> > > > > > <[e-mail]> wrote:
> > > > > > > Hi Saravana,
> > > > > > >
> > > > > > > Am Freitag, 1. Juli 2022, 02:37:14 CEST schrieb Saravana Kannan:
> > > > > > > > On Thu, Jun 23, 2022 at 5:08 AM Alexander Stein
> > > > > > > >
> > > > > > > > <[e-mail]> wrote:
> > > > > > > > > Hi,
> > > > > > > > >
> > > > > > > > > Am Dienstag, 21. Juni 2022, 09:28:43 CEST schrieb Tony
> Lindgren:
> > > > > > > > > > Hi,
> > > > > > > > > >
> > > > > > > > > > * Saravana Kannan <[e-mail]> [700101 02:00]:
> > > > > > > > > > > Now that fw_devlink=on by default and fw_devlink supports
> > > > > > > > > > > "power-domains" property, the execution will never get to
> > > > > > > > > > > the
> > > > > > > > > > > point
> > > > > > > > > > > where driver_deferred_probe_check_state() is called before
> > > > > > > > > > > the
> > > > > > > > > > > supplier
> > > > > > > > > > > has probed successfully or before deferred probe timeout
> > > > > > > > > > > has
> > > > > > > > > > > expired.
> > > > > > > > > > >
> > > > > > > > > > > So, delete the call and replace it with -ENODEV.
> > > > > > > > > >
> > > > > > > > > > Looks like this causes omaps to not boot in Linux next. With
> > > > > > > > > > this
> > > > > > > > > > simple-pm-bus fails to probe initially as the power-domain
> > > > > > > > > > is
> > > > > > > > > > not
> > > > > > > > > > yet available. On platform_probe() genpd_get_from_provider()
> > > > > > > > > > returns
> > > > > > > > > > -ENOENT.
> > > > > > > > > >
> > > > > > > > > > Seems like other stuff is potentially broken too, any ideas
> > > > > > > > > > on
> > > > > > > > > > how to fix this?
> > > > > > > > >
> > > > > > > > > I think I'm hit by this as well, although I do not get a
> > > > > > > > > lockup.
> > > > > > > > > In my case I'm using
> > > > > > > > > arch/arm64/boot/dts/freescale/imx8mq-tqma8mq-mba8mx.dts and
> > > > > > > > > probing of
> > > > > > > > > 38320000.blk-ctrl fails as the power-domain is not (yet)
> > > > > > > > > registed.
> > > > > > > >
> > > > > > > > Ok, took a look.
> > > > > > > >
> > > > > > > > The problem is that there are two drivers for the same device
> > > > > > > > and
> > > > > > > > they
> > > > > > > > both initialize this device.
> > > > > > > >
> > > > > > > >     gpc: gpc@303a0000 {
> > > > > > > >
> > > > > > > >         compatible = "fsl,imx8mq-gpc";
> > > > > > > >
> > > > > > > >     }
> > > > > > > >
> > > > > > > > $ git grep -l "fsl,imx7d-gpc" -- drivers/
> > > > > > > > drivers/irqchip/irq-imx-gpcv2.c
> > > > > > > > drivers/soc/imx/gpcv2.c
> > > > > > > >
> > > > > > > > IMHO, this is a bad/broken design.
> > > > > > > >
> > > > > > > > So what's happening is that fw_devlink will block the probe of
> > > > > > > > 38320000.blk-ctrl until 303a0000.gpc is initialized. And it
> > > > > > > > stops
> > > > > > > > blocking the probe of 38320000.blk-ctrl as soon as the first
> > > > > > > > driver
> > > > > > > > initializes the device. In this case, it's the irqchip driver.
> > > > > > > >
> > > > > > > > I'd recommend combining these drivers into one. Something like
> > > > > > > > the
> > > > > > > > patch I'm attaching (sorry for the attachment, copy-paste is
> > > > > > > > mangling
> > > > > > > > the tabs). Can you give it a shot please?
> > > > > > >
> > > > > > > I tried this patch and it delayed the driver initialization (those
> > > > > > > of
> > > > > > > UART
> > > > > > > as
> > > > > >
> > > > > > > well BTW). Unfortunately the driver fails the same way:
> > > > > > Thanks for testing the patch!
> > > > > >
> > > > > > > > [    1.125253] imx8m-blk-ctrl 38320000.blk-ctrl: error -ENODEV:
> > > > > > > > failed
> > > > > > > > to
> > > > > > >
> > > > > > > attach power domain "bus"
> > > > > > >
> > > > > > > More than that it even introduced some more errors:
> > > > > > > > [    0.008160] irq: no irq domain found for gpc@303a0000 !
> > > > > >
> > > > > > So the idea behind my change was that as long as the irqchip isn't
> > > > > > the
> > > > > > root of the irqdomain (might be using the terms incorrectly) like
> > > > > > the
> > > > > > gic, you can make it a platform driver. And I was trying to hack up
> > > > > > a
> > > > > > patch that's the equivalent of platform_irqchip_probe() (which just
> > > > > > ends up eventually calling the callback you use in
> > > > > > IRQCHIP_DECLARE().
> > > > > > I probably made some mistake in the quick hack that I'm sure if
> > > > > > fixable.
> > > > > >
> > > > > > > > [    0.013251] Failed to map interrupt for
> > > > > > > > /soc@0/bus@30400000/timer@306a0000
> > > > > >
> > > > > > However, this timer driver also uses TIMER_OF_DECLARE() which can't
> > > > > > handle failure to get the IRQ (because it's can't -EPROBE_DEFER).
> > > > > > So,
> > > > > > this means, the timer driver inturn needs to be converted to a
> > > > > > platform driver if it's supposed to work with the IRQCHIP_DECLARE()
> > > > > > being converted to a platform driver.
> > > > > >
> > > > > > But that's a can of worms not worth opening. But then I remembered
> > > > > > this simpler workaround will work and it is pretty much a variant of
> > > > > > the workaround that's already in the gpc's irqchip driver to allow
> > > > > > two
> > > > > > drivers to probe the same device (people really should stop doing
> > > > > > that).
> > > > > >
> > > > > > Can you drop my previous hack patch and try this instead please? I'm
> > > > > > 99% sure this will work.
> > > > > >
> > > > > > diff --git a/drivers/irqchip/irq-imx-gpcv2.c
> > > > > > b/drivers/irqchip/irq-imx-gpcv2.c index b9c22f764b4d..8a0e82067924
> > > > > > 100644
> > > > > > --- a/drivers/irqchip/irq-imx-gpcv2.c
> > > > > > +++ b/drivers/irqchip/irq-imx-gpcv2.c
> > > > > > @@ -283,6 +283,7 @@ static int __init imx_gpcv2_irqchip_init(struct
> > > > > > device_node *node,
> > > > > >
> > > > > >          * later the GPC power domain driver will not be skipped.
> > > > > >          */
> > > > > >
> > > > > >         of_node_clear_flag(node, OF_POPULATED);
> > > > > >
> > > > > > +       fwnode_dev_initialized(domain->fwnode, false);
> > > > > >
> > > > > >         return 0;
> > > > > >
> > > > > >  }
> > > > >
> > > > > Just to be sure here, I tried this patch on top of next-20220701 but
> > > > > unfortunately this doesn't fix the original problem either. The timer
> > > > > errors are gone though.
> > > >
> > > > To clarify, you had the timer issue only with my "combine drivers"
> > > > patch,
> > > > right?
> > >
> > > That's correct.
> > >
> > > > > The probe of imx8m-blk-ctrl got slightly delayed (from 0.74 to 0.90s
> > > > > printk
> > > > > time) but results in the identical error message.
> > > >
> > > > My guess is that the probe attempt of blk-ctrl is delayed now till gpc
> > > > probes (because of the device links getting created with the
> > > > fwnode_dev_initialized() fix), but by the time gpc probe finishes, the
> > > > power domains aren't registered yet because of the additional level of
> > > > device addition and probing.
> > > >
> > > > Can you try the attached patch please?
> > >
> > > Sure, it needed some small fixes though. But the error still is present.
> > >
> > > > And if that doesn't fix the issues, then enable the debug logs in the
> > > > following functions please and share the logs from boot till the
> > > > failure? If you can enable CONFIG_PRINTK_CALLER, that'd help too.
> > > > device_link_add()
> > > > fwnode_link_add()
> > > > fw_devlink_relax_cycle()
> > >
> > > I switched fw_devlink_relax_cycle() for fw_devlink_relax_link() as the
> > > former has no debug output here.
> > >
> > > For the record I added the following line to my kernel command line:
> > > > dyndbg="func device_link_add +p; func fwnode_link_add +p; func
> > >
> > > fw_devlink_relax_link +p"
> > >
> > > I attached the dmesg until the probe error to this mail. But I noticed the
> > >
> > > following lines which seem interesting:
> > > > [    1.466620][    T8] imx-pgc imx-pgc-domain.5: Linked as a consumer to
> > > > regulator.8
> > > > [    1.466743][    T8] imx-pgc imx-pgc-domain.5: imx_pgc_domain_probe:
> > > > Probe>
> > > succeeded
> > >
> > > > [    1.474733][    T8] imx-pgc imx-pgc-domain.6: Linked as a consumer to
> > >
> > > regulator.9
> > >
> > > > [    1.474774][    T8] imx-pgc imx-pgc-domain.6: imx_pgc_domain_probe:
> > > > Probe>
> > > succeeded
> >
> > I'm guessing this happens after the probe error.
> >
> > Ok, I looked at the dmesg logs and this pretty much confirms my
> > thought on why the probe ordering wasn't maintained.
> >
> > The power domains lack a compatible property, so the blk-ctrl is
> > linked as a consumer of the gpc instead:
> > [    0.343905][    T1] blk-ctrl@38320000 Linked as a fwnode consumer
> > to gpc@303a0000
> > [    0.343943][    T1] blk-ctrl@38320000 Linked as a fwnode consumer
> > to clock-controller@30380000
> > This ^^ is the device tree parsing figuring out the dependencies
> > between the DT nodes.
> >
> > [    0.368462][    T1] platform 38320000.blk-ctrl: Linked as a
> > consumer to 30380000.clock-controller
> > [    0.368542][    T1] platform 38320000.blk-ctrl: Linked as a
> > consumer to 303a0000.gpc
> > This ^^ is converting the DT node dependencies into device links.
> >
> > So, the only real options are:
> > 1. Fix DT and add a compatible string to the DT nodes.
> > 2. Move the initcall level of the regulator driver so the powerdomain
> > probe doesn't get deferred. Not ideal that we are playing initcall
> > chicken to handle the feature meant to remove the need for initcall
> > chicken. But I see these "device, but won't have a compatible
> > property" as exceptions and feel it's okay to have to play with
> > initcall levels to handle those.
> > 3. Provide a helper function that driver that do this (creating
> > devices for child DT nodes without compatible property) can use to
> > move/copy their consumer device links to the child devices they add.
> > And then fix up the gpc driver so that it copies the gpc -- blk-ctrl
> > device link to the proper power domain.
> > 4. I have another idea for how I could fix that at a driver core
> > level, but I'm not sure it'll work yet and its definitely not
> > something I want to try and get in for 5.19 -- too late for that IMHO.
> >
> > Want to give (2) a shot so that I can still try to keep the cleanup
> > series that caused this problem (that's the long term goal) while I
> > give (3) and (4) a shot for 5.20?
>
> Sure, I can give (2) a shot. Which initcall needs to be modified? You have a
> diff snippet?

All initcall for all the regulator drivers that feed this gpc power domain.

> BTW: this potentially affects all imx8m and imx7d as they have the same gpc
> binding.

Good point. That's why I was asking for your help :) -- you have more
context on these hardware.

> Can't say much about (1). I added Lucas Stach to recipients, he did a lot on
> this gpc driver.
> @Lucas: Do you have some input why the gpc power domains do not have a
> compatible? Is it reasonable to add them?

It's generally frowned upon to update the kernel in a way that it
breaks backwards compatibility with an older DT binary. That's why I
didn't ask about (1).

It's fairly trivial to get it to work if we (who is "we" here?) agree
it's okay to add the compatible property and break DT backwards
compatibility in this case.

-Saravana

Patch

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 739e52cd4aba..3e86772d5fac 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -2730,7 +2730,7 @@  static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
 		mutex_unlock(&gpd_list_lock);
 		dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
 			__func__, PTR_ERR(pd));
-		return driver_deferred_probe_check_state(base_dev);
+		return -ENODEV;
 	}
 
 	dev_dbg(dev, "adding to PM domain %s\n", pd->name);