Re: [PATCH v2] drm/i915/display: enable ccs modifiers on dg2

["Juha-Pekka Heikkilä" <juhapekka.heikkila@gmail.com>]

On 24/04/2026 14.42, Raag Jadav wrote:
> On Fri, Apr 24, 2026 at 11:44:57AM +0300, Jani Nikula wrote:
>> On Thu, 23 Apr 2026, Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com> wrote:
>>> Since Xe driver aux ccs enablement dg2 ccs modifiers have been
>>> disabled on both Xe and i915 drivers. Here allow dg2 to use
>>> ccs again for framebuffers.
>>>
>>> Fixes: 6a99e91a6ca8fec5882450128fb128265f86b32a ("drm/i915/display: Detect AuxCCS support via display parent interface")
>>
>> In kernel, there should be 12 characters of sha1.
> 
> I had a misconception that checkpatch already flags this, but it seems
> not? Or perhaps I'm not much informed about the history (if any)?

What checkpatch says is to use 12+ long sha when sha is shorter, like this:

WARNING: Please use correct Fixes: style 'Fixes: <12+ chars of sha1> 
("<title line>")'

hence I did put the full sha.

/Juha-Pekka


>> 'dim fixes <sha1>' gives you the correct format, and suggests Cc's
>> (though you probably shouldn't actually Cc all of them).
>>
>> For referencing commits in general, I have this handy alias in my
>> .gitconfig:
>>
>> [alias]
>> 	cite = log -1 --abbrev=12 '--format=%h (\"%s\")'
>>
>> $ git cite 6a99e91a6ca8fec5882450128fb128265f86b32a
>> 6a99e91a6ca8 ("drm/i915/display: Detect AuxCCS support via display parent interface")
>>
>> BR,
>> Jani.
>>
>>> Signed-off-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
>>> ---
>>>   drivers/gpu/drm/i915/i915_driver.c | 5 ++---
>>>   1 file changed, 2 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c
>>> index d31819758f3d..a4bd4f8e18b2 100644
>>> --- a/drivers/gpu/drm/i915/i915_driver.c
>>> +++ b/drivers/gpu/drm/i915/i915_driver.c
>>> @@ -750,9 +750,8 @@ static bool has_auxccs(struct drm_device *drm)
>>>   {
>>>   	struct drm_i915_private *i915 = to_i915(drm);
>>>   
>>> -	return IS_GRAPHICS_VER(i915, 9, 12) ||
>>> -	       IS_ALDERLAKE_P(i915) ||
>>> -	       IS_METEORLAKE(i915);
>>> +	return IS_GRAPHICS_VER(i915, 9, 12) &&
>>> +		!HAS_FLAT_CCS(i915);
>>>   }
>>>   
>>>   static bool has_fenced_regions(struct drm_device *drm)
>>
>> -- 
>> Jani Nikula, Intel