diff mbox

[1/2] Revert "ARM: OMAP2+: Fix serial init for device tree based booting"

Message ID 1373539986-27272-2-git-send-email-rnayak@ti.com (mailing list archive)
State New, archived
Headers show

Commit Message

Rajendra Nayak July 11, 2013, 10:53 a.m. UTC
This reverts commit 82702ea11ddfe0e43382e1fa5b66d807d8114916.

The above commit stubbed out omap_serial_early_init() in case of
DT build thinking it was doing the serial port initializations.

omap_serial_early_init() however does not do the serial port
inits (its instead done by omap_serial_init_port()) instead
it sets the HWMOD_INIT_NO_IDLE and HWMOD_INIT_NO_RESET flags
for the console uart which causes hwmod to avoid doing a reset
followed by the idling of the console uart.

This is still needed even in the DT case.

Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Reported-by: Mark Jackson <mpfj-list@newflow.co.uk>
Reported-by: Vaibhav Bedia <vaibhav.bedia@ti.com>
---
 arch/arm/mach-omap2/serial.c |    3 ---
 1 file changed, 3 deletions(-)

Comments

Tony Lindgren July 12, 2013, 7:20 a.m. UTC | #1
* Rajendra Nayak <rnayak@ti.com> [130711 03:59]:
> This reverts commit 82702ea11ddfe0e43382e1fa5b66d807d8114916.
> 
> The above commit stubbed out omap_serial_early_init() in case of
> DT build thinking it was doing the serial port initializations.

Well not really. It was done to cut dependency between device
tree initialized drivers and pdata initialized drivers.
 
> omap_serial_early_init() however does not do the serial port
> inits (its instead done by omap_serial_init_port()) instead
> it sets the HWMOD_INIT_NO_IDLE and HWMOD_INIT_NO_RESET flags
> for the console uart which causes hwmod to avoid doing a reset
> followed by the idling of the console uart.
> 
> This is still needed even in the DT case.

This fix is going the wrong way.

The console is working fine with DT based booting for me,
except for the earlyprintk fix needed.

And there should not be any need to parse cmdline for console
as omap-serial.c sets it up and already knows about it.

Care to state what exactly this attempts to fix and for which
omaps? If this is only needed for am33xx, then why?

Regards,

Tony
 
> Signed-off-by: Rajendra Nayak <rnayak@ti.com>
> Reported-by: Mark Jackson <mpfj-list@newflow.co.uk>
> Reported-by: Vaibhav Bedia <vaibhav.bedia@ti.com>
> ---
>  arch/arm/mach-omap2/serial.c |    3 ---
>  1 file changed, 3 deletions(-)
> 
> diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
> index 3a674de..58d5b56 100644
> --- a/arch/arm/mach-omap2/serial.c
> +++ b/arch/arm/mach-omap2/serial.c
> @@ -175,9 +175,6 @@ static char *cmdline_find_option(char *str)
>  
>  static int __init omap_serial_early_init(void)
>  {
> -	if (of_have_populated_dt())
> -		return -ENODEV;
> -
>  	do {
>  		char oh_name[MAX_UART_HWMOD_NAME_LEN];
>  		struct omap_hwmod *oh;
> -- 
> 1.7.9.5
> 
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Rajendra Nayak July 12, 2013, 7:31 a.m. UTC | #2
On Friday 12 July 2013 12:50 PM, Tony Lindgren wrote:
> * Rajendra Nayak <rnayak@ti.com> [130711 03:59]:
>> This reverts commit 82702ea11ddfe0e43382e1fa5b66d807d8114916.
>>
>> The above commit stubbed out omap_serial_early_init() in case of
>> DT build thinking it was doing the serial port initializations.
> 
> Well not really. It was done to cut dependency between device
> tree initialized drivers and pdata initialized drivers.
>  
>> omap_serial_early_init() however does not do the serial port
>> inits (its instead done by omap_serial_init_port()) instead
>> it sets the HWMOD_INIT_NO_IDLE and HWMOD_INIT_NO_RESET flags
>> for the console uart which causes hwmod to avoid doing a reset
>> followed by the idling of the console uart.
>>
>> This is still needed even in the DT case.
> 
> This fix is going the wrong way.
> 
> The console is working fine with DT based booting for me,
> except for the earlyprintk fix needed.

It works on omap4 and omap5. It won't work on any
am33xx devices.

> 
> And there should not be any need to parse cmdline for console
> as omap-serial.c sets it up and already knows about it.
> 
> Care to state what exactly this attempts to fix and for which
> omaps? If this is only needed for am33xx, then why?

Yes, this is needed only for am33xx because am33xx hwmod rightly
had the hwmod flags for NO_IDLE and NO_RESET removed and omap4
and omap5 wrongly still carry them around.

Just try applying PATCH 2/2 of this series and it won't work on the
omap4 sdp anymore.

regards,
Rajendra

> 
> Regards,
> 
> Tony
>  
>> Signed-off-by: Rajendra Nayak <rnayak@ti.com>
>> Reported-by: Mark Jackson <mpfj-list@newflow.co.uk>
>> Reported-by: Vaibhav Bedia <vaibhav.bedia@ti.com>
>> ---
>>  arch/arm/mach-omap2/serial.c |    3 ---
>>  1 file changed, 3 deletions(-)
>>
>> diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
>> index 3a674de..58d5b56 100644
>> --- a/arch/arm/mach-omap2/serial.c
>> +++ b/arch/arm/mach-omap2/serial.c
>> @@ -175,9 +175,6 @@ static char *cmdline_find_option(char *str)
>>  
>>  static int __init omap_serial_early_init(void)
>>  {
>> -	if (of_have_populated_dt())
>> -		return -ENODEV;
>> -
>>  	do {
>>  		char oh_name[MAX_UART_HWMOD_NAME_LEN];
>>  		struct omap_hwmod *oh;
>> -- 
>> 1.7.9.5
>>

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Tony Lindgren July 12, 2013, 8:03 a.m. UTC | #3
* Rajendra Nayak <rnayak@ti.com> [130712 00:38]:
> On Friday 12 July 2013 12:50 PM, Tony Lindgren wrote:
> > * Rajendra Nayak <rnayak@ti.com> [130711 03:59]:
> >> This reverts commit 82702ea11ddfe0e43382e1fa5b66d807d8114916.
> >>
> >> The above commit stubbed out omap_serial_early_init() in case of
> >> DT build thinking it was doing the serial port initializations.
> > 
> > Well not really. It was done to cut dependency between device
> > tree initialized drivers and pdata initialized drivers.
> >  
> >> omap_serial_early_init() however does not do the serial port
> >> inits (its instead done by omap_serial_init_port()) instead
> >> it sets the HWMOD_INIT_NO_IDLE and HWMOD_INIT_NO_RESET flags
> >> for the console uart which causes hwmod to avoid doing a reset
> >> followed by the idling of the console uart.
> >>
> >> This is still needed even in the DT case.
> > 
> > This fix is going the wrong way.
> > 
> > The console is working fine with DT based booting for me,
> > except for the earlyprintk fix needed.
> 
> It works on omap4 and omap5. It won't work on any
> am33xx devices.

OK. I assume the regular serial onsole works just fine, what does
not work is the earlyprintk for am33xx?

> > And there should not be any need to parse cmdline for console
> > as omap-serial.c sets it up and already knows about it.
> > 
> > Care to state what exactly this attempts to fix and for which
> > omaps? If this is only needed for am33xx, then why?
> 
> Yes, this is needed only for am33xx because am33xx hwmod rightly
> had the hwmod flags for NO_IDLE and NO_RESET removed and omap4
> and omap5 wrongly still carry them around.

OK.
 
> Just try applying PATCH 2/2 of this series and it won't work on the
> omap4 sdp anymore.

OK, so that's only for earlyprintk then?

If so, it seems the right fix is to set the NO_IDLE and NO_RESET
flags based on ifdef CONFIG_DEBUG_OMAP4UART3 etc as that is selected
in the Kconfig now.

The current code in mach-omap2/serial.c is wrong, and is a hack
needed for the pdata based booting. What's broken is that
omap_serial_early_init() parses the cmdline for console, which
itself is pretty nasty, and it won't work the right way as
there's nothing stopping from having the earlycon in a different
UART from the serial console. So we just want to get rid of the
whole mach-omap2/serial.c once we're all DT.

So to summarize, we have two bugs:

1. Omap hwmod code can reset UART while earlycon may be using
   it. The fix to this is to use NO_IDLE and NO_RESET flags in
   the hwmod code if CONFIG_DEBUG_OMAPxUARTy is specified.

2. A bug in drivers/tty/serial/omap-serial.c where the
   missing context loss count can cause NULL context to be
   initialized during driver probe causing port to hang for
   earlycon. The fix for that is what Felipe has suggested or
   fix it in the driver by removing the context loss count usage
   and detect the need for context restore based on the UART
   state.

Or am I still missing something?

Regards,

Tony
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Rajendra Nayak July 12, 2013, 8:59 a.m. UTC | #4
On Friday 12 July 2013 01:33 PM, Tony Lindgren wrote:
> * Rajendra Nayak <rnayak@ti.com> [130712 00:38]:
>> On Friday 12 July 2013 12:50 PM, Tony Lindgren wrote:
>>> * Rajendra Nayak <rnayak@ti.com> [130711 03:59]:
>>>> This reverts commit 82702ea11ddfe0e43382e1fa5b66d807d8114916.
>>>>
>>>> The above commit stubbed out omap_serial_early_init() in case of
>>>> DT build thinking it was doing the serial port initializations.
>>>
>>> Well not really. It was done to cut dependency between device
>>> tree initialized drivers and pdata initialized drivers.
>>>  
>>>> omap_serial_early_init() however does not do the serial port
>>>> inits (its instead done by omap_serial_init_port()) instead
>>>> it sets the HWMOD_INIT_NO_IDLE and HWMOD_INIT_NO_RESET flags
>>>> for the console uart which causes hwmod to avoid doing a reset
>>>> followed by the idling of the console uart.
>>>>
>>>> This is still needed even in the DT case.
>>>
>>> This fix is going the wrong way.
>>>
>>> The console is working fine with DT based booting for me,
>>> except for the earlyprintk fix needed.
>>
>> It works on omap4 and omap5. It won't work on any
>> am33xx devices.
> 
> OK. I assume the regular serial onsole works just fine, what does
> not work is the earlyprintk for am33xx?

Yes, thats right.

> 
>>> And there should not be any need to parse cmdline for console
>>> as omap-serial.c sets it up and already knows about it.
>>>
>>> Care to state what exactly this attempts to fix and for which
>>> omaps? If this is only needed for am33xx, then why?
>>
>> Yes, this is needed only for am33xx because am33xx hwmod rightly
>> had the hwmod flags for NO_IDLE and NO_RESET removed and omap4
>> and omap5 wrongly still carry them around.
> 
> OK.
>  
>> Just try applying PATCH 2/2 of this series and it won't work on the
>> omap4 sdp anymore.
> 
> OK, so that's only for earlyprintk then?

yes,

> 
> If so, it seems the right fix is to set the NO_IDLE and NO_RESET
> flags based on ifdef CONFIG_DEBUG_OMAP4UART3 etc as that is selected
> in the Kconfig now.

ok makes sense. It seems like the static data in hwmod can be populated
based on these defines? something like

/* uart3 */
static struct omap_hwmod omap44xx_uart3_hwmod = {
        .name           = "uart3",
        .class          = &omap44xx_uart_hwmod_class,
        .clkdm_name     = "l4_per_clkdm",
#ifdef CONFIG_DEBUG_OMAP4UART3
        .flags          = HWMOD_INIT_NO_IDLE | HWMOD_INIT_NO_RESET |
                                HWMOD_SWSUP_SIDLE_ACT,
#else
        .flags          = HWMOD_SWSUP_SIDLE_ACT,
#endif
        .main_clk       = "func_48m_fclk",
        .prcm = {
                .omap4 = {
                        .clkctrl_offs = OMAP4_CM_L4PER_UART3_CLKCTRL_OFFSET,
                        .context_offs = OMAP4_RM_L4PER_UART3_CONTEXT_OFFSET,
                        .modulemode   = MODULEMODE_SWCTRL,
                },
        },
};

And same way for others? That way the cmdline parsing can be done away
with even for the non-DT case.

> 
> The current code in mach-omap2/serial.c is wrong, and is a hack
> needed for the pdata based booting. What's broken is that
> omap_serial_early_init() parses the cmdline for console, which
> itself is pretty nasty, and it won't work the right way as
> there's nothing stopping from having the earlycon in a different
> UART from the serial console. So we just want to get rid of the
> whole mach-omap2/serial.c once we're all DT.
> 
> So to summarize, we have two bugs:
> 
> 1. Omap hwmod code can reset UART while earlycon may be using
>    it. The fix to this is to use NO_IDLE and NO_RESET flags in
>    the hwmod code if CONFIG_DEBUG_OMAPxUARTy is specified.
> 
> 2. A bug in drivers/tty/serial/omap-serial.c where the
>    missing context loss count can cause NULL context to be
>    initialized during driver probe causing port to hang for
>    earlycon. The fix for that is what Felipe has suggested or
>    fix it in the driver by removing the context loss count usage
>    and detect the need for context restore based on the UART
>    state.
> 
> Or am I still missing something?

No, thats pretty much the 2 issues we have.

regards,
Rajendra
> 
> Regards,
> 
> Tony
> 

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Tony Lindgren July 12, 2013, 9:18 a.m. UTC | #5
* Rajendra Nayak <rnayak@ti.com> [130712 02:06]:
> On Friday 12 July 2013 01:33 PM, Tony Lindgren wrote:
> > 
> > OK, so that's only for earlyprintk then?
> 
> yes,
> 
> > 
> > If so, it seems the right fix is to set the NO_IDLE and NO_RESET
> > flags based on ifdef CONFIG_DEBUG_OMAP4UART3 etc as that is selected
> > in the Kconfig now.
> 
> ok makes sense. It seems like the static data in hwmod can be populated
> based on these defines? something like
> 
> /* uart3 */
> static struct omap_hwmod omap44xx_uart3_hwmod = {
>         .name           = "uart3",
>         .class          = &omap44xx_uart_hwmod_class,
>         .clkdm_name     = "l4_per_clkdm",
> #ifdef CONFIG_DEBUG_OMAP4UART3
>         .flags          = HWMOD_INIT_NO_IDLE | HWMOD_INIT_NO_RESET |
>                                 HWMOD_SWSUP_SIDLE_ACT,
> #else
>         .flags          = HWMOD_SWSUP_SIDLE_ACT,
> #endif
>         .main_clk       = "func_48m_fclk",
>         .prcm = {
>                 .omap4 = {
>                         .clkctrl_offs = OMAP4_CM_L4PER_UART3_CLKCTRL_OFFSET,
>                         .context_offs = OMAP4_RM_L4PER_UART3_CONTEXT_OFFSET,
>                         .modulemode   = MODULEMODE_SWCTRL,
>                 },
>         },
> };
> 
> And same way for others? That way the cmdline parsing can be done away
> with even for the non-DT case.

Yes we can do it that way. How about add a common macro for it if
it's always the same? Then the .flags line would be just:

#define HWMOD_OMAP_UART_FLAGS(soc, port)
...

	.flags		= HWMOD_OMAP_UART_FLAGS(4, 3),

> > The current code in mach-omap2/serial.c is wrong, and is a hack
> > needed for the pdata based booting. What's broken is that
> > omap_serial_early_init() parses the cmdline for console, which
> > itself is pretty nasty, and it won't work the right way as
> > there's nothing stopping from having the earlycon in a different
> > UART from the serial console. So we just want to get rid of the
> > whole mach-omap2/serial.c once we're all DT.
> > 
> > So to summarize, we have two bugs:
> > 
> > 1. Omap hwmod code can reset UART while earlycon may be using
> >    it. The fix to this is to use NO_IDLE and NO_RESET flags in
> >    the hwmod code if CONFIG_DEBUG_OMAPxUARTy is specified.
> > 
> > 2. A bug in drivers/tty/serial/omap-serial.c where the
> >    missing context loss count can cause NULL context to be
> >    initialized during driver probe causing port to hang for
> >    earlycon. The fix for that is what Felipe has suggested or
> >    fix it in the driver by removing the context loss count usage
> >    and detect the need for context restore based on the UART
> >    state.
> > 
> > Or am I still missing something?
> 
> No, thats pretty much the 2 issues we have.

OK thanks good to hear it's limited to earlycon issues.

Regards,

Tony
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Rajendra Nayak July 12, 2013, 9:22 a.m. UTC | #6
On Friday 12 July 2013 02:48 PM, Tony Lindgren wrote:
> * Rajendra Nayak <rnayak@ti.com> [130712 02:06]:
>> On Friday 12 July 2013 01:33 PM, Tony Lindgren wrote:
>>>
>>> OK, so that's only for earlyprintk then?
>>
>> yes,
>>
>>>
>>> If so, it seems the right fix is to set the NO_IDLE and NO_RESET
>>> flags based on ifdef CONFIG_DEBUG_OMAP4UART3 etc as that is selected
>>> in the Kconfig now.
>>
>> ok makes sense. It seems like the static data in hwmod can be populated
>> based on these defines? something like
>>
>> /* uart3 */
>> static struct omap_hwmod omap44xx_uart3_hwmod = {
>>         .name           = "uart3",
>>         .class          = &omap44xx_uart_hwmod_class,
>>         .clkdm_name     = "l4_per_clkdm",
>> #ifdef CONFIG_DEBUG_OMAP4UART3
>>         .flags          = HWMOD_INIT_NO_IDLE | HWMOD_INIT_NO_RESET |
>>                                 HWMOD_SWSUP_SIDLE_ACT,
>> #else
>>         .flags          = HWMOD_SWSUP_SIDLE_ACT,
>> #endif
>>         .main_clk       = "func_48m_fclk",
>>         .prcm = {
>>                 .omap4 = {
>>                         .clkctrl_offs = OMAP4_CM_L4PER_UART3_CLKCTRL_OFFSET,
>>                         .context_offs = OMAP4_RM_L4PER_UART3_CONTEXT_OFFSET,
>>                         .modulemode   = MODULEMODE_SWCTRL,
>>                 },
>>         },
>> };
>>
>> And same way for others? That way the cmdline parsing can be done away
>> with even for the non-DT case.
> 
> Yes we can do it that way. How about add a common macro for it if
> it's always the same? Then the .flags line would be just:
> 
> #define HWMOD_OMAP_UART_FLAGS(soc, port)
> ...
> 
> 	.flags		= HWMOD_OMAP_UART_FLAGS(4, 3),

Right, that seems much cleaner. I will send a patch out for it and get rid
of all the cmdline parsing in serial.c

regards
Rajendra
> 
>>> The current code in mach-omap2/serial.c is wrong, and is a hack
>>> needed for the pdata based booting. What's broken is that
>>> omap_serial_early_init() parses the cmdline for console, which
>>> itself is pretty nasty, and it won't work the right way as
>>> there's nothing stopping from having the earlycon in a different
>>> UART from the serial console. So we just want to get rid of the
>>> whole mach-omap2/serial.c once we're all DT.
>>>
>>> So to summarize, we have two bugs:
>>>
>>> 1. Omap hwmod code can reset UART while earlycon may be using
>>>    it. The fix to this is to use NO_IDLE and NO_RESET flags in
>>>    the hwmod code if CONFIG_DEBUG_OMAPxUARTy is specified.
>>>
>>> 2. A bug in drivers/tty/serial/omap-serial.c where the
>>>    missing context loss count can cause NULL context to be
>>>    initialized during driver probe causing port to hang for
>>>    earlycon. The fix for that is what Felipe has suggested or
>>>    fix it in the driver by removing the context loss count usage
>>>    and detect the need for context restore based on the UART
>>>    state.
>>>
>>> Or am I still missing something?
>>
>> No, thats pretty much the 2 issues we have.
> 
> OK thanks good to hear it's limited to earlycon issues.
> 
> Regards,
> 
> Tony
> 

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Tony Lindgren July 12, 2013, 9:46 a.m. UTC | #7
* Rajendra Nayak <rnayak@ti.com> [130712 02:29]:
>
> Right, that seems much cleaner. I will send a patch out for it and get rid
> of all the cmdline parsing in serial.c

Oh that's right, then it should not be needed for legacy pdata based
booting either :)

Regards,

Tony
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Rajendra Nayak July 12, 2013, 12:12 p.m. UTC | #8
On Friday 12 July 2013 02:48 PM, Tony Lindgren wrote:
> * Rajendra Nayak <rnayak@ti.com> [130712 02:06]:
>> On Friday 12 July 2013 01:33 PM, Tony Lindgren wrote:
>>>
>>> OK, so that's only for earlyprintk then?
>>
>> yes,
>>
>>>
>>> If so, it seems the right fix is to set the NO_IDLE and NO_RESET
>>> flags based on ifdef CONFIG_DEBUG_OMAP4UART3 etc as that is selected
>>> in the Kconfig now.
>>
>> ok makes sense. It seems like the static data in hwmod can be populated
>> based on these defines? something like
>>
>> /* uart3 */
>> static struct omap_hwmod omap44xx_uart3_hwmod = {
>>         .name           = "uart3",
>>         .class          = &omap44xx_uart_hwmod_class,
>>         .clkdm_name     = "l4_per_clkdm",
>> #ifdef CONFIG_DEBUG_OMAP4UART3
>>         .flags          = HWMOD_INIT_NO_IDLE | HWMOD_INIT_NO_RESET |
>>                                 HWMOD_SWSUP_SIDLE_ACT,
>> #else
>>         .flags          = HWMOD_SWSUP_SIDLE_ACT,
>> #endif
>>         .main_clk       = "func_48m_fclk",
>>         .prcm = {
>>                 .omap4 = {
>>                         .clkctrl_offs = OMAP4_CM_L4PER_UART3_CLKCTRL_OFFSET,
>>                         .context_offs = OMAP4_RM_L4PER_UART3_CONTEXT_OFFSET,
>>                         .modulemode   = MODULEMODE_SWCTRL,
>>                 },
>>         },
>> };
>>
>> And same way for others? That way the cmdline parsing can be done away
>> with even for the non-DT case.
> 
> Yes we can do it that way. How about add a common macro for it if
> it's always the same? Then the .flags line would be just:
> 
> #define HWMOD_OMAP_UART_FLAGS(soc, port)
> ...
> 
> 	.flags		= HWMOD_OMAP_UART_FLAGS(4, 3),

I started doing this and ended up with equal number of #ifdefs in the
header :( Was the intention of doing this to reduce the #ifdefs? in which
case maybe I am doing something wrong.

> 
>>> The current code in mach-omap2/serial.c is wrong, and is a hack
>>> needed for the pdata based booting. What's broken is that
>>> omap_serial_early_init() parses the cmdline for console, which
>>> itself is pretty nasty, and it won't work the right way as
>>> there's nothing stopping from having the earlycon in a different
>>> UART from the serial console. So we just want to get rid of the
>>> whole mach-omap2/serial.c once we're all DT.
>>>
>>> So to summarize, we have two bugs:
>>>
>>> 1. Omap hwmod code can reset UART while earlycon may be using
>>>    it. The fix to this is to use NO_IDLE and NO_RESET flags in
>>>    the hwmod code if CONFIG_DEBUG_OMAPxUARTy is specified.
>>>
>>> 2. A bug in drivers/tty/serial/omap-serial.c where the
>>>    missing context loss count can cause NULL context to be
>>>    initialized during driver probe causing port to hang for
>>>    earlycon. The fix for that is what Felipe has suggested or
>>>    fix it in the driver by removing the context loss count usage
>>>    and detect the need for context restore based on the UART
>>>    state.
>>>
>>> Or am I still missing something?
>>
>> No, thats pretty much the 2 issues we have.
> 
> OK thanks good to hear it's limited to earlycon issues.
> 
> Regards,
> 
> Tony
> 

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Tony Lindgren July 12, 2013, 12:33 p.m. UTC | #9
* Rajendra Nayak <rnayak@ti.com> [130712 05:18]:
> On Friday 12 July 2013 02:48 PM, Tony Lindgren wrote:
> > * Rajendra Nayak <rnayak@ti.com> [130712 02:06]:
> >> On Friday 12 July 2013 01:33 PM, Tony Lindgren wrote:
> >>>
> >>> OK, so that's only for earlyprintk then?
> >>
> >> yes,
> >>
> >>>
> >>> If so, it seems the right fix is to set the NO_IDLE and NO_RESET
> >>> flags based on ifdef CONFIG_DEBUG_OMAP4UART3 etc as that is selected
> >>> in the Kconfig now.
> >>
> >> ok makes sense. It seems like the static data in hwmod can be populated
> >> based on these defines? something like
> >>
> >> /* uart3 */
> >> static struct omap_hwmod omap44xx_uart3_hwmod = {
> >>         .name           = "uart3",
> >>         .class          = &omap44xx_uart_hwmod_class,
> >>         .clkdm_name     = "l4_per_clkdm",
> >> #ifdef CONFIG_DEBUG_OMAP4UART3
> >>         .flags          = HWMOD_INIT_NO_IDLE | HWMOD_INIT_NO_RESET |
> >>                                 HWMOD_SWSUP_SIDLE_ACT,
> >> #else
> >>         .flags          = HWMOD_SWSUP_SIDLE_ACT,
> >> #endif
> >>         .main_clk       = "func_48m_fclk",
> >>         .prcm = {
> >>                 .omap4 = {
> >>                         .clkctrl_offs = OMAP4_CM_L4PER_UART3_CLKCTRL_OFFSET,
> >>                         .context_offs = OMAP4_RM_L4PER_UART3_CONTEXT_OFFSET,
> >>                         .modulemode   = MODULEMODE_SWCTRL,
> >>                 },
> >>         },
> >> };
> >>
> >> And same way for others? That way the cmdline parsing can be done away
> >> with even for the non-DT case.
> > 
> > Yes we can do it that way. How about add a common macro for it if
> > it's always the same? Then the .flags line would be just:
> > 
> > #define HWMOD_OMAP_UART_FLAGS(soc, port)
> > ...
> > 
> > 	.flags		= HWMOD_OMAP_UART_FLAGS(4, 3),
> 
> I started doing this and ended up with equal number of #ifdefs in the
> header :( Was the intention of doing this to reduce the #ifdefs? in which
> case maybe I am doing something wrong.

Hmm can't you use ## for substition in the macro to reduce the ifdefs
and have just one macro instead one for every debug port?

Regards,

Tony
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diff mbox

Patch

diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
index 3a674de..58d5b56 100644
--- a/arch/arm/mach-omap2/serial.c
+++ b/arch/arm/mach-omap2/serial.c
@@ -175,9 +175,6 @@  static char *cmdline_find_option(char *str)
 
 static int __init omap_serial_early_init(void)
 {
-	if (of_have_populated_dt())
-		return -ENODEV;
-
 	do {
 		char oh_name[MAX_UART_HWMOD_NAME_LEN];
 		struct omap_hwmod *oh;