Re: [Intel-gfx] [PATCH] drm/i915: Start using plane scale factor for relative data rate

[Jani Nikula <jani.nikula@linux.intel.com>]

On Thu, 20 Jul 2023, "Lisovskiy, Stanislav" <stanislav.lisovskiy@intel.com> wrote:
> On Wed, Jul 19, 2023 at 01:48:33PM +0300, Stanislav Lisovskiy wrote:
>> BSpec clearly instructs us to use plane scale factor when calculating
>> relative data rate to be used when allocating DDB blocks for each plane.
>> For some reason we use scale factor for data_rate calculation, which is
>> used for BW calculations, however we are not using it for DDB calculations.
>> So lets fix it as described in BSpec 68907.
>> 
>> Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
>> ---
>>  drivers/gpu/drm/i915/display/intel_atomic_plane.c | 7 ++++++-
>>  1 file changed, 6 insertions(+), 1 deletion(-)
>> 
>> diff --git a/drivers/gpu/drm/i915/display/intel_atomic_plane.c b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
>> index 7d9578ebae556..60a492e186ab8 100644
>> --- a/drivers/gpu/drm/i915/display/intel_atomic_plane.c
>> +++ b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
>> @@ -212,6 +212,7 @@ intel_plane_relative_data_rate(const struct intel_crtc_state *crtc_state,
>>  	struct intel_plane *plane = to_intel_plane(plane_state->uapi.plane);
>>  	const struct drm_framebuffer *fb = plane_state->hw.fb;
>>  	int width, height;
>> +	unsigned int rel_data_rate;
>>  
>>  	if (plane->id == PLANE_CURSOR)
>>  		return 0;
>> @@ -241,7 +242,11 @@ intel_plane_relative_data_rate(const struct intel_crtc_state *crtc_state,
>>  		height /= 2;
>>  	}
>>  
>> -	return width * height * fb->format->cpp[color_plane];
>> +	rel_data_rate = width * height * fb->format->cpp[color_plane];
>> +
>> +	return intel_adjusted_rate(&plane_state->uapi.src,
>> +				   &plane_state->uapi.dst,
>> +				   rel_data_rate);
>>  }
>>  
>>  int intel_plane_calc_min_cdclk(struct intel_atomic_state *state,
>> -- 
>> 2.37.3
>> 
>
> IGT failures are irrelevant here(test is aborted due to some timeout issue).

Going through old mails... I think errors like that still warrant a
retest before merging, because it can mask real issues that now won't
get tested.

BR,
Jani.

-- 
Jani Nikula, Intel Open Source Graphics Center