Re: [PATCH v2] ARM: dts: exynos: Enable Mixer node for Exynos5800 Peach Pi machine

[Marek Szyprowski <m.szyprowski@samsung.com>]

Hi Guillaume,

On 2017-12-12 11:43, Guillaume Tucker wrote:
> On 12/12/17 10:17, Marek Szyprowski wrote:
>> Hi Krzysztof,
>>
>> On 2017-12-12 11:09, Krzysztof Kozlowski wrote:
>>> On Tue, Dec 12, 2017 at 10:55 AM, Krzysztof Kozlowski 
>>> <krzk@kernel.org> wrote:
>>>> On Tue, Dec 12, 2017 at 8:42 AM, Javier Martinez Canillas
>>>> <javierm@redhat.com> wrote:
>>>>> Commit 1cb686c08d12 ("ARM: dts: exynos: Add status property to 
>>>>> Exynos 542x
>>>>> Mixer nodes") disabled the Mixer node by default in the DTSI and 
>>>>> enabled
>>>>> for each Exynos 542x DTS. But unfortunately it missed to enable it 
>>>>> for the
>>>>> Exynos5800 Peach Pi machine, since the 5800 is also an 542x SoC 
>>>>> variant.
>>>>>
>>>>> Fixes: 1cb686c08d12 ("ARM: dts: exynos: Add status property to 
>>>>> Exynos 542x Mixer nodes")
>>>>> Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
>>>>> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
>>>>>
>>>>> ---
>>>>>
>>>>> Changes in v2:
>>>>> - Remove RFT tag.
>>>> Thanks guys! However I still would like to see a tested-by for this on
>>>> Peach Pi (AFAIU, Marek's only acked the code/solution).
>>> On the other hand I could just apply it for my for-next branch and
>>> we'll see if it fixes kernel-ci boot tests... Not a nice way of
>>> testing but apparently no one has Peach Pi.
>>
>> Frankly, I don't expect that this will solve the boot hang issue on 
>> PeachPi.
>> However it should at least hide the unbalanced regulator issue.
>
> We have a peach-pi in our LAVA lab so I've tested it and
> actually, it does fix the hang on v4.15-rc3:
>
>   https://lava.collabora.co.uk/scheduler/job/1019877
>   https://lava.collabora.co.uk/scheduler/job/1019878
>
> I ran it twice and it booted both times.  I also ran the same
> boot tests with the same kernel but the dtb from v4.15-rc3
> without the fix to double check and these failed:
>
>   https://lava.collabora.co.uk/scheduler/job/1019879
>   https://lava.collabora.co.uk/scheduler/job/1019880
>
>
> Tested-by: Guillaume Tucker <guillaume.tucker@collabora.com>
>
>
> Thanks for the fix!

Well, thanks for the test! It proves that there the boot failure is
caused by an issue somewhere in the error path of Exynos DRM, Analogix
DP, Simple Panel or other drivers.

This patch simply hides it by fixing the source issue of the Exynos
DRM initialization failure. :-)

I hope Javier will be able to investigate the discussed hang issue
later, as fixing it is also imho important.

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland