Commit 50575eb5 authored by Krunoslav Kovac's avatar Krunoslav Kovac Committed by Alex Deucher
Browse files

drm/amd/display: Only use EETF when maxCL > max display 



[Why&How]
BT.2390 EETF is used for tone mapping/range reduction.
Say display is 0.1 - 500 nits.
The problematic case is when content is 0-400. We apply EETF because
0<0.1 so we need to reduce the range by 0.1.

In the commit, we ignore the bottom range. Most displays map 0 to min and
then have a ramp to 0.1, so sending 0.1 is actually >0.1.
Furthermode, HW that uses 3D LUT also assumes min=0.

Signed-off-by: default avatarKrunoslav Kovac <Krunoslav.Kovac@amd.com>
Reviewed-by: default avatarAric Cyr <Aric.Cyr@amd.com>
Acked-by: default avatarLeo Li <sunpeng.li@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 622a88c8

drivers/gpu/drm/amd/display/modules/color/color_gamma.c

+1 −5
Original line number Diff line number Diff line
@@ -959,11 +959,7 @@ static bool build_freesync_hdr(struct pwl_float_data_ex *rgb_regamma, 
	if (fs_params->max_display < 100) // cap at 100 at the top

		max_display = dc_fixpt_from_int(100);



	if (fs_params->min_content < fs_params->min_display)

		use_eetf = true;

	else

		min_content = min_display;



	// only max used, we don't adjust min luminance

	if (fs_params->max_content > fs_params->max_display)

		use_eetf = true;

	else