From: Fangzhi Zuo <[email protected]> [Why & How] The HDMI Forum VSDB reports the maximum DSC color depth a sink supports. This maximum is cumulative: a sink that reports 12 bpc also supports 10 and 8 bpc.
The previous code used exact "== 10" and "== 12" comparisons chained with else-if, so a 12 bpc sink only set frl_dsc_12bpc and never set frl_dsc_10bpc, incorrectly narrowing the DSC bpc range usable with that sink. Use ">= 10" and a separate ">= 12" check so a sink advertising a higher maximum also enables the lower DSC bit depths it supports. Reviewed-by: Alex Hung <[email protected]> Signed-off-by: Fangzhi Zuo <[email protected]> Signed-off-by: Ray Wu <[email protected]> --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c | 5 +++-- .../drm/amd/display/amdgpu_dm/tests/amdgpu_dm_helpers_test.c | 2 +- 2 files changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c index 93fd5f251a6c..836c06772a68 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c @@ -1228,9 +1228,10 @@ void populate_hdmi_info_from_connector(bool enable_frl, struct drm_hdmi_info *hd edid_caps->max_frl_rate = get_max_frl_rate(hdmi->max_lanes, hdmi->max_frl_rate_per_lane); edid_caps->frl_dsc_support = hdmi->dsc_cap.v_1p2; if (edid_caps->frl_dsc_support) { - if (hdmi->dsc_cap.bpc_supported == 10) + /* HF-VSDB DSC max bpc is cumulative: >=12 implies 10 and 8. */ + if (hdmi->dsc_cap.bpc_supported >= 10) edid_caps->frl_dsc_10bpc = true; - else if (hdmi->dsc_cap.bpc_supported == 12) + if (hdmi->dsc_cap.bpc_supported >= 12) edid_caps->frl_dsc_12bpc = true; edid_caps->frl_dsc_all_bpp = hdmi->dsc_cap.all_bpp; edid_caps->frl_dsc_native_420 = hdmi->dsc_cap.native_420; diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_helpers_test.c b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_helpers_test.c index d4232648d8e6..ceedb8745267 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_helpers_test.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_helpers_test.c @@ -982,7 +982,7 @@ static void dm_test_populate_hdmi_frl_dsc_12bpc(struct kunit *test) KUNIT_EXPECT_EQ(test, caps->max_frl_rate, 2); KUNIT_EXPECT_TRUE(test, caps->frl_dsc_support); - KUNIT_EXPECT_FALSE(test, caps->frl_dsc_10bpc); + KUNIT_EXPECT_TRUE(test, caps->frl_dsc_10bpc); KUNIT_EXPECT_TRUE(test, caps->frl_dsc_12bpc); KUNIT_EXPECT_EQ(test, caps->frl_dsc_max_slices, 7); KUNIT_EXPECT_EQ(test, caps->frl_dsc_max_frl_rate, 1); -- 2.43.0
