From 5a32ee170ff1aefcc0be637f17af1513015972c4 Mon Sep 17 00:00:00 2001
From: Roman Li <roman.li@amd.com>
Date: Thu, 19 May 2022 14:41:16 -0400
Subject: drm/amd/display: Cap OLED brightness per max frame-average luminance
Git-commit: 4fd17f2ac0aa4e48823ac2ede5b050fb70300bf4
Patch-mainline: v5.19-rc3
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
[Why]
For OLED eDP the Display Manager uses max_cll value as a limit
for brightness control.
max_cll defines the content light luminance for individual pixel.
Whereas max_fall defines frame-average level luminance.
The user may not observe the difference in brightness in between
max_fall and max_cll.
That negatively impacts the user experience.
[How]
Use max_fall value instead of max_cll as a limit for brightness control.
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Acked-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 70be67a56673..39b425d83bb1 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -2812,7 +2812,7 @@ static struct drm_mode_config_helper_funcs amdgpu_dm_mode_config_helperfuncs = {
static void update_connector_ext_caps(struct amdgpu_dm_connector *aconnector)
{
- u32 max_cll, min_cll, max, min, q, r;
+ u32 max_avg, min_cll, max, min, q, r;
struct amdgpu_dm_backlight_caps *caps;
struct amdgpu_display_manager *dm;
struct drm_connector *conn_base;
@@ -2842,7 +2842,7 @@ static void update_connector_ext_caps(struct amdgpu_dm_connector *aconnector)
caps = &dm->backlight_caps[i];
caps->ext_caps = &aconnector->dc_link->dpcd_sink_ext_caps;
caps->aux_support = false;
- max_cll = conn_base->hdr_sink_metadata.hdmi_type1.max_cll;
+ max_avg = conn_base->hdr_sink_metadata.hdmi_type1.max_fall;
min_cll = conn_base->hdr_sink_metadata.hdmi_type1.min_cll;
if (caps->ext_caps->bits.oled == 1 /*||
@@ -2870,8 +2870,8 @@ static void update_connector_ext_caps(struct amdgpu_dm_connector *aconnector)
* The results of the above expressions can be verified at
* pre_computed_values.
*/
- q = max_cll >> 5;
- r = max_cll % 32;
+ q = max_avg >> 5;
+ r = max_avg % 32;
max = (1 << q) * pre_computed_values[r];
// min luminance: maxLum * (CV/255)^2 / 100
--
2.38.1