[PATCH] drm/amd/display: Not to call dpcd_set_source_specific_data during resume.

[Harry Wentland]

On 2022-01-10 04:06, Rajib Mahapatra wrote:
> [Why]
> During resume path, dpcd_set_source_specific_data is taking
> extra time when core_link_write_dpcd fails on DP_SOURCE_OUI+0x03
> and DP_SOURCE_MINIMUM_HBLANK_SUPPORTED. Here,aux->transfer fails
> with multiple retries and consume sigficantamount time during
> S0i3 resume.
> 
> [How]
> Not to call dpcd_set_source_specific_data during resume path
> when there is no oled panel connected and achieve faster resume
> during S0i3.
> 
> Signed-off-by: Rajib Mahapatra <rajib.mahapatra at amd.com>
> ---
>  drivers/gpu/drm/amd/display/dc/core/dc_link.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
> index c0bdc23702c8..04086c199dbb 100644
> --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
> +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
> @@ -892,7 +892,8 @@ static bool dc_link_detect_helper(struct dc_link *link,
>  		(!link->dc->config.allow_edp_hotplug_detection)) &&
>  		link->local_sink) {
>  		// need to re-write OUI and brightness in resume case
> -		if (link->connector_signal == SIGNAL_TYPE_EDP) {
> +		if (link->connector_signal == SIGNAL_TYPE_EDP &&
> +			(link->dpcd_sink_ext_caps.bits.oled == 1)) {

Is the source specific data only used by OLED panels?

Do we know that this won't lead to regressions with any features on non-OLED panels?

Harry

>  			dpcd_set_source_specific_data(link);
>  			msleep(post_oui_delay);
>  			dc_link_set_default_brightness_aux(link);