Re: LCDC problem after commit 794d78fea51504bad3880d14f354a9847f318f25

[Damian Hobson-Garcia <dhobsong@igel.co.jp>]

Hi Laurent,

On 2011/08/19 15:24, Laurent Pinchart wrote:
> Hi Damian,
> 
> On Friday 12 August 2011 11:59:10 Laurent Pinchart wrote:
>> On Thursday 11 August 2011 21:37:04 Rafael J. Wysocki wrote:
>>> On Thursday, August 11, 2011, Laurent Pinchart wrote:
>>>> On Tuesday 09 August 2011 12:48:44 Magnus Damm wrote:
>>>>> On Mon, Aug 8, 2011 at 10:46 AM, Magnus Damm wrote:
>>>>>> On Mon, Aug 8, 2011 at 8:25 AM, Rafael J. Wysocki wrote:
>>>>>>> Unfortunately, after commit
>>>>>>> 794d78fea51504bad3880d14f354a9847f318f25 (drivers: sh: late
>>>>>>> disabling of clocks V2) the LCDC screen on my Mackerel board goes
>>>>>>> off (late) during boot and cannot be turned on by any way AFAICS
>>>>>>> (the backlight remains on, though).
>>>>>>>
>>>>>>> It looks like the late disabling of clocks interacts badly with
>>>>>>> the clock management done by PM domains.
>>>>>>
>>>>>> This is most likely showing a so-far-not-handled clock dependency
>>>>>> for the LCDC hardware. I'll have a look.
>>>>>
>>>>> Further investigation shows that this only triggers when the MERAM is
>>>>> enabled in the kernel configuration using
>>>>> CONFIG_FB_SH_MOBILE_MERAM=y. So this seems more related to MERAM
>>>>> power management than LCDC.
>>>>>
>>>>> Digging a bit deeper makes it clear that the sh_mobile_meram.c driver
>>>>> in upstream doesn't seem to include any Runtime PM code. I recall
>>>>> seeing various versions posted to the mailing list.
>>>>>
>>>>> Laurent [CC], can you please provide us with a list of outstanding
>>>>> LCDC/MERAM patches to make this work as expected? I realize there are
>>>>> quite a few outstanding LCDC patches, but if possible please provide
>>>>> a list of the bare minimum to make this work with 3.1-rc.
>>>>
>>>> I've pushed my pending patches to
>>>> http://git.linuxtv.org/pinchartl/fbdev.git in the pm-domains branch.
>>>> The first 19 patches have been picked from mailing lists. Hopefully
>>>> they're the latest versions that have been posted. The next 11 patches
>>>> shouldn't be required to enable runtime PM with the MERAM, but they
>>>> provide code cleanup and bug fixes.
>>>>
>>>> Are Rafael' and Damian's patches ready for mainline ? If so, when will
>>>> they be pulled ? They're more than one month old, I was expecting them
>>>> to hit v3.1- rc1. The backlog is growing, which makes collaboration
>>>> more difficult.
>>>
>>> Which of my patches are you referring to in particular?
>>
>> My bad, your patches are in v3.1-rc1. I had rebased my branch on top of the
>> wrong tag. We still need to push Damian's MERAM runtime PM patches, as well
>> as mine.
> 
> Do you plan to push your MERAM runtime PM patches (available at 
> http://git.linuxtv.org/pinchartl/fbdev.git/shortlog/refs/heads/pm-domains 
> rebased on top of v3.1-rc2) ?
> 

Sorry for my late reply.  Yes the plan was to push the MERAM runtime
patches. I see that you've already included them in a PULL request, cc:d
to the list, so that's fine by me.

Thanks,
Damian