diff mbox series

[v2] of: address: Work around missing device_type property in pcie nodes

Message ID 20200819094255.474565-1-maz@kernel.org (mailing list archive)
State New, archived
Headers show
Series [v2] of: address: Work around missing device_type property in pcie nodes | expand

Commit Message

Marc Zyngier Aug. 19, 2020, 9:42 a.m. UTC
Recent changes to the DT PCI bus parsing made it mandatory for
device tree nodes describing a PCI controller to have the
'device_type = "pci"' property for the node to be matched.

Although this follows the letter of the specification, it
breaks existing device-trees that have been working fine
for years.  Rockchip rk3399-based systems are a prime example
of such collateral damage, and have stopped discovering their
PCI bus.

In order to paper over it, let's add a workaround to the code
matching the device type, and accept as PCI any node that is
named "pcie",

A warning will hopefully nudge the user into updating their
DT to a fixed version if they can, but the incentive is
obviously pretty small.

Fixes: 2f96593ecc37 ("of_address: Add bus type match for pci ranges parser")
Suggested-by: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/of/address.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

Comments

Rob Herring Aug. 19, 2020, 10:30 p.m. UTC | #1
On Wed, 19 Aug 2020 10:42:55 +0100, Marc Zyngier wrote:
> Recent changes to the DT PCI bus parsing made it mandatory for
> device tree nodes describing a PCI controller to have the
> 'device_type = "pci"' property for the node to be matched.
> 
> Although this follows the letter of the specification, it
> breaks existing device-trees that have been working fine
> for years.  Rockchip rk3399-based systems are a prime example
> of such collateral damage, and have stopped discovering their
> PCI bus.
> 
> In order to paper over it, let's add a workaround to the code
> matching the device type, and accept as PCI any node that is
> named "pcie",
> 
> A warning will hopefully nudge the user into updating their
> DT to a fixed version if they can, but the incentive is
> obviously pretty small.
> 
> Fixes: 2f96593ecc37 ("of_address: Add bus type match for pci ranges parser")
> Suggested-by: Rob Herring <robh+dt@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
> ---
>  drivers/of/address.c | 16 +++++++++++++++-
>  1 file changed, 15 insertions(+), 1 deletion(-)
> 

Applied, thanks!
Niklas Söderlund Sept. 30, 2020, 4:27 p.m. UTC | #2
Hi Marc,

I'm afraid this commit breaks booting my rk3399 device.

I bisected the problem to this patch merged as [1]. I'm testing on a 
Scarlet device and I'm using the unmodified upstream  
rk3399-gru-scarlet-inx.dtb for my tests.

The problem I'm experience is a black screen after the bootloader and 
the device is none responsive over the network. I have no serial console 
to this device so I'm afraid I can't tell you if there is anything 
useful on to aid debugging there.

If I try to test one commit earlier [2] the system boots as expected and 
everything works as it did for me in v5.8 and earlier. I have worked 
little with this device and have no clue about what is really on the PCI 
buss. But running from [2] I have this info about PCI if it's helpful, 
please ask if somethings missing.

# dmesg | grep -i pci
[    0.003943] PCI/MSI: /interrupt-controller@fee00000/interrupt-controller@fee20000 domain created
[    0.922022] PCI: CLS 0 bytes, default 64
[    0.941517] rockchip-pcie f8000000.pcie: host bridge /pcie@f8000000 ranges:
[    0.941577] rockchip-pcie f8000000.pcie:      MEM 0x00fa000000..0x00fbefffff -> 0x00fa000000
[    0.941962] rockchip-pcie f8000000.pcie: GPIO lookup for consumer ep
[    0.941981] rockchip-pcie f8000000.pcie: using device tree for GPIO lookup
[    0.942018] of_get_named_gpiod_flags: parsed 'ep-gpios' property of node '/pcie@f8000000[0]' - status (0)
[    0.942255] rockchip-pcie f8000000.pcie: no vpcie12v regulator found
[    4.196248] ehci-pci: EHCI PCI platform driver
[    4.214639] ohci-pci: OHCI PCI platform driver


# ls /sys/bus/{pci,pci_express}/devices
/sys/bus/pci/devices:

/sys/bus/pci_express/devices:


# ls /sys/bus/{pci,pci_express}/drivers
/sys/bus/pci/drivers:
cavium_rng_pf  cavium_rng_vf  dwc3-haps  ehci-pci  exar_serial  ohci-pci  pcieport  serial  xhci_hcd

/sys/bus/pci_express/drivers:
pcie_pme


# ls /sys/bus/platform/drivers/rockchip-{pcie,pcie-phy}
/sys/bus/platform/drivers/rockchip-pcie:
bind  uevent  unbind

/sys/bus/platform/drivers/rockchip-pcie-phy:
bind  ff770000.syscon:pcie-phy  uevent  unbind

1. d1ac0002dd297069 ("of: address: Work around missing device_type property in pcie nodes")
2. 43647929175e2cd3 ("dt: writing-schema: Miscellaneous grammar fixes")

On 2020-08-19 10:42:55 +0100, Marc Zyngier wrote:
> Recent changes to the DT PCI bus parsing made it mandatory for
> device tree nodes describing a PCI controller to have the
> 'device_type = "pci"' property for the node to be matched.
> 
> Although this follows the letter of the specification, it
> breaks existing device-trees that have been working fine
> for years.  Rockchip rk3399-based systems are a prime example
> of such collateral damage, and have stopped discovering their
> PCI bus.
> 
> In order to paper over it, let's add a workaround to the code
> matching the device type, and accept as PCI any node that is
> named "pcie",
> 
> A warning will hopefully nudge the user into updating their
> DT to a fixed version if they can, but the incentive is
> obviously pretty small.
> 
> Fixes: 2f96593ecc37 ("of_address: Add bus type match for pci ranges parser")
> Suggested-by: Rob Herring <robh+dt@kernel.org>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
> ---
>  drivers/of/address.c | 16 +++++++++++++++-
>  1 file changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/of/address.c b/drivers/of/address.c
> index 590493e04b01..b37bd9cc2810 100644
> --- a/drivers/of/address.c
> +++ b/drivers/of/address.c
> @@ -128,15 +128,29 @@ static unsigned int of_bus_pci_get_flags(const __be32 *addr)
>   * PCI bus specific translator
>   */
>  
> +static bool of_node_is_pcie(struct device_node *np)
> +{
> +	bool is_pcie = of_node_name_eq(np, "pcie");
> +
> +	if (is_pcie)
> +		pr_warn_once("%pOF: Missing device_type\n", np);
> +
> +	return is_pcie;
> +}
> +
>  static int of_bus_pci_match(struct device_node *np)
>  {
>  	/*
>   	 * "pciex" is PCI Express
>  	 * "vci" is for the /chaos bridge on 1st-gen PCI powermacs
>  	 * "ht" is hypertransport
> +	 *
> +	 * If none of the device_type match, and that the node name is
> +	 * "pcie", accept the device as PCI (with a warning).
>  	 */
>  	return of_node_is_type(np, "pci") || of_node_is_type(np, "pciex") ||
> -		of_node_is_type(np, "vci") || of_node_is_type(np, "ht");
> +		of_node_is_type(np, "vci") || of_node_is_type(np, "ht") ||
> +		of_node_is_pcie(np);
>  }
>  
>  static void of_bus_pci_count_cells(struct device_node *np,
> -- 
> 2.27.0
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Marc Zyngier Sept. 30, 2020, 5:23 p.m. UTC | #3
Hi Niklas,

[+ Samuel]

On 2020-09-30 17:27, Niklas Söderlund wrote:
> Hi Marc,
> 
> I'm afraid this commit breaks booting my rk3399 device.
> 
> I bisected the problem to this patch merged as [1]. I'm testing on a
> Scarlet device and I'm using the unmodified upstream
> rk3399-gru-scarlet-inx.dtb for my tests.
> 
> The problem I'm experience is a black screen after the bootloader and
> the device is none responsive over the network. I have no serial 
> console
> to this device so I'm afraid I can't tell you if there is anything
> useful on to aid debugging there.
> 
> If I try to test one commit earlier [2] the system boots as expected 
> and
> everything works as it did for me in v5.8 and earlier. I have worked
> little with this device and have no clue about what is really on the 
> PCI
> buss. But running from [2] I have this info about PCI if it's helpful,
> please ask if somethings missing.

Please see the thread at [1]. The problem was reported a few weeks back
by Samuel, and I was expecting Rob and Lorenzo to push a fix for this.

Rob, Lorenzo, any update on this?

         M.

[1] 
https://lore.kernel.org/linux-devicetree/20200829164920.7d28e01a@DUFFMAN/
Niklas Söderlund Sept. 30, 2020, 5:37 p.m. UTC | #4
Hi Marc,

On 2020-09-30 18:23:21 +0100, Marc Zyngier wrote:
> Hi Niklas,
> 
> [+ Samuel]
> 
> On 2020-09-30 17:27, Niklas Söderlund wrote:
> > Hi Marc,
> > 
> > I'm afraid this commit breaks booting my rk3399 device.
> > 
> > I bisected the problem to this patch merged as [1]. I'm testing on a
> > Scarlet device and I'm using the unmodified upstream
> > rk3399-gru-scarlet-inx.dtb for my tests.
> > 
> > The problem I'm experience is a black screen after the bootloader and
> > the device is none responsive over the network. I have no serial console
> > to this device so I'm afraid I can't tell you if there is anything
> > useful on to aid debugging there.
> > 
> > If I try to test one commit earlier [2] the system boots as expected and
> > everything works as it did for me in v5.8 and earlier. I have worked
> > little with this device and have no clue about what is really on the PCI
> > buss. But running from [2] I have this info about PCI if it's helpful,
> > please ask if somethings missing.
> 
> Please see the thread at [1]. The problem was reported a few weeks back
> by Samuel, and I was expecting Rob and Lorenzo to push a fix for this.

Thanks for providing a solution.

> 
> Rob, Lorenzo, any update on this?
> 
>         M.
> 
> [1]
> https://lore.kernel.org/linux-devicetree/20200829164920.7d28e01a@DUFFMAN/
> -- 
> Jazz is not dead. It just smells funny...
Rob Herring Sept. 30, 2020, 8:34 p.m. UTC | #5
On Wed, Sep 30, 2020 at 12:37 PM Niklas Söderlund
<niklas.soderlund@ragnatech.se> wrote:
>
> Hi Marc,
>
> On 2020-09-30 18:23:21 +0100, Marc Zyngier wrote:
> > Hi Niklas,
> >
> > [+ Samuel]
> >
> > On 2020-09-30 17:27, Niklas Söderlund wrote:
> > > Hi Marc,
> > >
> > > I'm afraid this commit breaks booting my rk3399 device.
> > >
> > > I bisected the problem to this patch merged as [1]. I'm testing on a
> > > Scarlet device and I'm using the unmodified upstream
> > > rk3399-gru-scarlet-inx.dtb for my tests.
> > >
> > > The problem I'm experience is a black screen after the bootloader and
> > > the device is none responsive over the network. I have no serial console
> > > to this device so I'm afraid I can't tell you if there is anything
> > > useful on to aid debugging there.
> > >
> > > If I try to test one commit earlier [2] the system boots as expected and
> > > everything works as it did for me in v5.8 and earlier. I have worked
> > > little with this device and have no clue about what is really on the PCI
> > > buss. But running from [2] I have this info about PCI if it's helpful,
> > > please ask if somethings missing.
> >
> > Please see the thread at [1]. The problem was reported a few weeks back
> > by Samuel, and I was expecting Rob and Lorenzo to push a fix for this.
>
> Thanks for providing a solution.
>
> >
> > Rob, Lorenzo, any update on this?

The fix is in Bjorn's tree[1].

Bjorn, going to send this to Linus before v5.9 is out?

Rob

[1] https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git/log/?h=for-linus
Bjorn Helgaas Sept. 30, 2020, 10:51 p.m. UTC | #6
On Wed, Sep 30, 2020 at 03:34:10PM -0500, Rob Herring wrote:
> On Wed, Sep 30, 2020 at 12:37 PM Niklas Söderlund
> <niklas.soderlund@ragnatech.se> wrote:
> >
> > Hi Marc,
> >
> > On 2020-09-30 18:23:21 +0100, Marc Zyngier wrote:
> > > Hi Niklas,
> > >
> > > [+ Samuel]
> > >
> > > On 2020-09-30 17:27, Niklas Söderlund wrote:
> > > > Hi Marc,
> > > >
> > > > I'm afraid this commit breaks booting my rk3399 device.
> > > >
> > > > I bisected the problem to this patch merged as [1]. I'm testing on a
> > > > Scarlet device and I'm using the unmodified upstream
> > > > rk3399-gru-scarlet-inx.dtb for my tests.
> > > >
> > > > The problem I'm experience is a black screen after the bootloader and
> > > > the device is none responsive over the network. I have no serial console
> > > > to this device so I'm afraid I can't tell you if there is anything
> > > > useful on to aid debugging there.
> > > >
> > > > If I try to test one commit earlier [2] the system boots as expected and
> > > > everything works as it did for me in v5.8 and earlier. I have worked
> > > > little with this device and have no clue about what is really on the PCI
> > > > buss. But running from [2] I have this info about PCI if it's helpful,
> > > > please ask if somethings missing.
> > >
> > > Please see the thread at [1]. The problem was reported a few weeks back
> > > by Samuel, and I was expecting Rob and Lorenzo to push a fix for this.
> >
> > Thanks for providing a solution.
> >
> > >
> > > Rob, Lorenzo, any update on this?
> 
> The fix is in Bjorn's tree[1].
> 
> Bjorn, going to send this to Linus before v5.9 is out?

Definitely, thanks for the reminder.  I'm assuming the fix in question
is https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git/commit/?h=for-linus&id=e338eecf3fe79054e8a31b8c39a1234b5acfdabe

> [1] https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git/log/?h=for-linus
Niklas Söderlund Sept. 30, 2020, 11:48 p.m. UTC | #7
Hi Bjorn,

On 2020-09-30 17:51:54 -0500, Bjorn Helgaas wrote:
> On Wed, Sep 30, 2020 at 03:34:10PM -0500, Rob Herring wrote:
> > On Wed, Sep 30, 2020 at 12:37 PM Niklas Söderlund
> > <niklas.soderlund@ragnatech.se> wrote:
> > >
> > > Hi Marc,
> > >
> > > On 2020-09-30 18:23:21 +0100, Marc Zyngier wrote:
> > > > Hi Niklas,
> > > >
> > > > [+ Samuel]
> > > >
> > > > On 2020-09-30 17:27, Niklas Söderlund wrote:
> > > > > Hi Marc,
> > > > >
> > > > > I'm afraid this commit breaks booting my rk3399 device.
> > > > >
> > > > > I bisected the problem to this patch merged as [1]. I'm testing on a
> > > > > Scarlet device and I'm using the unmodified upstream
> > > > > rk3399-gru-scarlet-inx.dtb for my tests.
> > > > >
> > > > > The problem I'm experience is a black screen after the bootloader and
> > > > > the device is none responsive over the network. I have no serial console
> > > > > to this device so I'm afraid I can't tell you if there is anything
> > > > > useful on to aid debugging there.
> > > > >
> > > > > If I try to test one commit earlier [2] the system boots as expected and
> > > > > everything works as it did for me in v5.8 and earlier. I have worked
> > > > > little with this device and have no clue about what is really on the PCI
> > > > > buss. But running from [2] I have this info about PCI if it's helpful,
> > > > > please ask if somethings missing.
> > > >
> > > > Please see the thread at [1]. The problem was reported a few weeks back
> > > > by Samuel, and I was expecting Rob and Lorenzo to push a fix for this.
> > >
> > > Thanks for providing a solution.
> > >
> > > >
> > > > Rob, Lorenzo, any update on this?
> > 
> > The fix is in Bjorn's tree[1].
> > 
> > Bjorn, going to send this to Linus before v5.9 is out?
> 
> Definitely, thanks for the reminder.  I'm assuming the fix in question
> is https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git/commit/?h=for-linus&id=e338eecf3fe79054e8a31b8c39a1234b5acfdabe

That patch solves my boot problem.

Cherry-picked and tested directly on-top of v5.9-rc7 (which fails to 
boot without the patch in question).

> 
> > [1] https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git/log/?h=for-linus
diff mbox series

Patch

diff --git a/drivers/of/address.c b/drivers/of/address.c
index 590493e04b01..b37bd9cc2810 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -128,15 +128,29 @@  static unsigned int of_bus_pci_get_flags(const __be32 *addr)
  * PCI bus specific translator
  */
 
+static bool of_node_is_pcie(struct device_node *np)
+{
+	bool is_pcie = of_node_name_eq(np, "pcie");
+
+	if (is_pcie)
+		pr_warn_once("%pOF: Missing device_type\n", np);
+
+	return is_pcie;
+}
+
 static int of_bus_pci_match(struct device_node *np)
 {
 	/*
  	 * "pciex" is PCI Express
 	 * "vci" is for the /chaos bridge on 1st-gen PCI powermacs
 	 * "ht" is hypertransport
+	 *
+	 * If none of the device_type match, and that the node name is
+	 * "pcie", accept the device as PCI (with a warning).
 	 */
 	return of_node_is_type(np, "pci") || of_node_is_type(np, "pciex") ||
-		of_node_is_type(np, "vci") || of_node_is_type(np, "ht");
+		of_node_is_type(np, "vci") || of_node_is_type(np, "ht") ||
+		of_node_is_pcie(np);
 }
 
 static void of_bus_pci_count_cells(struct device_node *np,