Re: [ATTN] Re: [PATCH v4 5/7] ARM: Exynos: remove code for MFC custom reserved memory handling

[Krzysztof Kozlowski <k.kozlowski@samsung.com>]

On 06/03/2016 11:59 AM, Sylwester Nawrocki wrote:
> On 06/03/2016 08:57 AM, Krzysztof Kozlowski wrote:
>> On 06/02/2016 07:25 PM, Javier Martinez Canillas wrote:
>>> On 06/02/2016 12:31 PM, Krzysztof Kozlowski wrote:
>>>> On 06/02/2016 05:20 PM, Javier Martinez Canillas wrote:
>>>>> On 05/30/2016 03:28 AM, Krzysztof Kozlowski wrote:
>>>>>> On 05/24/2016 03:31 PM, Marek Szyprowski wrote:
>>>>>>> Once MFC driver has been converted to generic reserved memory bindings,
>>>>>>> there is no need for custom memory reservation code.
>>>>>>>
>>>>>>> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
>>>>>>> ---
>>>>>>>  arch/arm/mach-exynos/Makefile      |  2 -
>>>>>>>  arch/arm/mach-exynos/exynos.c      | 19 --------
>>>>>>>  arch/arm/mach-exynos/mfc.h         | 16 -------
>>>>>>>  arch/arm/mach-exynos/s5p-dev-mfc.c | 93 -----------------------------
>>>>>>>  4 files changed, 130 deletions(-)
>>>>>>>  delete mode 100644 arch/arm/mach-exynos/mfc.h
>>>>>>>  delete mode 100644 arch/arm/mach-exynos/s5p-dev-mfc.c
>>>>>>
>>>>>> Thanks, applied.
>>>>>
>>>>> This patch can't be applied before patches 2/5 and 3/5, or the custom
>>>>> memory regions reservation will break with the current s5p-mfc driver.
>>>>
>>>> Yes, I know. As I understood from talk with Marek, the driver is broken
>>>> now so continuous work was not chosen. If it is not correct and full
>>>
>>> It's true that the driven is currently broken in mainline and is not really
>>> stable, I posted fixes for all the issues I found (mostly in module removal
>>> and insert paths).
>>>
>>> But with just the following patch from Ayaka on top of mainline, I'm able to
>>> have video decoding working: https://lkml.org/lkml/2016/5/6/577
>>
>> Which is still a "future" patch, not current state...
>>>
>>> Marek mentioned that bisectability is only partially broken because the old
>>> binding will still work after this series if IOMMU is enabled (because the
>>> properties are ignored in this case). But will break if IOMMU isn't enabled
>>> which will be the case for some boards that fails to boot with IOMMU due the
>>> bootloader leaving the FIMD enabled doing DMA operations automatically AFAIU. 
>>>
>>> Now, I'm OK with not keeping backwards compatibility for the MFC dt bindings
>>> since arguably the driver has been broken for a long time and nobody cared
>>> and also I don't think anyone in practice boots a new kernel with an old DTB
>>> for Exynos.
>>>
>>> But I don't think is correct to introduce a new issue as is the case if this
>>> patch is applied before the previous patches in the series since this causes
>>> the driver to probe to fail and the following warn on boot (while it used to
>>> at least probe correctly in mainline):
>>
>> Okay but the patches will go through separate tree. This is not a
>> problem, as I said, I just need a stable tag from media tree with first
>> four patches (Mauro?).
> 
> I have prepared a topic branch including media patches from this patch
> series and the dependency fix patches from Javier and Marek.
> So this could be used as a topic branch to pull into media master branch
> and a dependency topic branch for Krzysztof's samsung-soc tree.
> Mauro, can we do it this way? I already talked to Kamil about this.
> 
> ---8<----
> The following changes since commit 1a695a905c18548062509178b98bc91e67510864:
> 
>   Linux 4.7-rc1 (2016-05-29 09:29:24 -0700)
> 
> are available in the git repository at:
> 
>   git://linuxtv.org/snawrocki/samsung.git for-v4.8/media/exynos-mfc
> 
> for you to fetch changes up to 04f776734c4e03e33111d3d5a994b589870df623:
> 
>   media: s5p-mfc: add iommu support (2016-06-03 11:13:45 +0200)

Thanks Sylwester! Although this is branch not a tag but I believe it
will stay stable. Pulled. I will apply Exynos-specific patches on top of it.

Best regards,
Krzysztof