5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Melissa Wen <mwen@xxxxxxxxxx> commit 57a943ebfcdb4a97fbb409640234bdb44bfa1953 upstream. For DRM legacy gamma, AMD display manager applies implicit sRGB degamma using a pre-defined sRGB transfer function. It works fine for DCN2 family where degamma ROM and custom curves go to the same color block. But, on DCN3+, degamma is split into two blocks: degamma ROM for pre-defined TFs and `gamma correction` for user/custom curves and degamma ROM settings doesn't apply to cursor plane. To get DRM legacy gamma working as expected, enable cursor degamma ROM for implict sRGB degamma on HW with this configuration. Cc: stable@xxxxxxxxxxxxxxx Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2803 Fixes: 96b020e2163f ("drm/amd/display: check attr flag before set cursor degamma on DCN3+") Signed-off-by: Melissa Wen <mwen@xxxxxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -8794,6 +8794,13 @@ static void handle_cursor_update(struct attributes.rotation_angle = 0; attributes.attribute_flags.value = 0; + /* Enable cursor degamma ROM on DCN3+ for implicit sRGB degamma in DRM + * legacy gamma setup. + */ + if (crtc_state->cm_is_degamma_srgb && + adev->dm.dc->caps.color.dpp.gamma_corr) + attributes.attribute_flags.bits.ENABLE_CURSOR_DEGAMMA = 1; + attributes.pitch = afb->base.pitches[0] / afb->base.format->cpp[0]; if (crtc_state->stream) {
