ACK/Cmnt: [PATCH 1/1][SRU G/H] drm/amd/display: Try YCbCr420 color when YCbCr444 fails

[Krzysztof Kozlowski]

On 28/04/2021 10:00, Werner Sembach wrote:
> BugLink: https://bugs.launchpad.net/bugs/1922754
> 
> When encoder validation of a display mode fails, retry with less bandwidth
> heavy YCbCr420 color mode, if available. This enables some HDMI 1.4 setups
> to support 4k60Hz output, which previously failed silently.
> 
> On some setups, while the monitor and the gpu support display modes with
> pixel clocks of up to 600MHz, the link encoder might not. This prevents
> YCbCr444 and RGB encoding for 4k60Hz, but YCbCr420 encoding might still be
> possible. However, which color mode is used is decided before the link
> encoder capabilities are checked. This patch fixes the problem by retrying
> to find a display mode with YCbCr420 enforced and using it, if it is
> valid.
> 
> Reviewed-by: Harry Wentland <harry.wentland at amd.com>
> Signed-off-by: Werner Sembach <wse at tuxedocomputers.com>
> Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
> ---
>  drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 9 +++++++++
>  1 file changed, 9 insertions(+)

With resolving of the comments provided by Stefan:
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski at canonical.com>


Best regards,
Krzysztof