On Mon, Nov 25, 2024 at 02:09:59PM +0200, Jani Nikula wrote:
> encoder->get_hw_state() returns false for DP MST, and currently always
> interprets 128b/132b as MST. Therefore the DDI MST mode checks in
> intel_ddi_connector_get_hw_state() are redundant.
>
> Prepare for future, and handle 128b/132b SST and warn on 8b/10b MST.
>
> Cc: Imre Deak <imre.deak@xxxxxxxxx>
> Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx>
Looks ok to me:
Reviewed-by: Imre Deak <imre.deak@xxxxxxxxx>
> ---
> drivers/gpu/drm/i915/display/intel_ddi.c | 11 +++++++----
> 1 file changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
> index e25b712bf03b..7d37ddd9ad12 100644
> --- a/drivers/gpu/drm/i915/display/intel_ddi.c
> +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
> @@ -731,6 +731,7 @@ bool intel_ddi_connector_get_hw_state(struct intel_connector *intel_connector)
> if (!wakeref)
> return false;
>
> + /* Note: This returns false for DP MST primary encoders. */
> if (!encoder->get_hw_state(encoder, &pipe)) {
> ret = false;
> goto out;
> @@ -752,12 +753,14 @@ bool intel_ddi_connector_get_hw_state(struct intel_connector *intel_connector)
> } else if (ddi_mode == TRANS_DDI_MODE_SELECT_DP_SST) {
> ret = type == DRM_MODE_CONNECTOR_eDP ||
> type == DRM_MODE_CONNECTOR_DisplayPort;
> - } else if (ddi_mode == TRANS_DDI_MODE_SELECT_DP_MST ||
> - (ddi_mode == TRANS_DDI_MODE_SELECT_FDI_OR_128B132B && HAS_DP20(display))) {
> + } else if (ddi_mode == TRANS_DDI_MODE_SELECT_FDI_OR_128B132B && HAS_DP20(display)) {
> /*
> - * If the transcoder is in MST state then connector isn't
> - * connected.
> + * encoder->get_hw_state() should have bailed out on MST. This
> + * must be SST and non-eDP.
> */
> + ret = type == DRM_MODE_CONNECTOR_DisplayPort;
> + } else if (drm_WARN_ON(display->drm, ddi_mode == TRANS_DDI_MODE_SELECT_DP_MST)) {
> + /* encoder->get_hw_state() should have bailed out on MST. */
> ret = false;
> } else {
> ret = false;
> --
> 2.39.5
>
