Commit c6266862 authored by Stanislav Lisovskiy's avatar Stanislav Lisovskiy
Browse files

drm/i915: Fix intel_dp_mst_compute_link_config 



We currently always exit that bpp loop because
drm_dp_atomic_find_vcpi_slots doesn't care if we actually
can fit those or not.
I think that wasn't the initial intention here, especially when
we keep trying with lower bpps, we are supposed to keep trying
until we actually find some _working_ configuration, which isn't the
case here.
So added that drm_dp_mst_check here, so that we can make sure
that try all the bpps before we fail.

Reviewed-by: default avatarVinod Govindapillai <vinod.govindapillai@intel.com>
Signed-off-by: default avatarStanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220905085744.29637-3-stanislav.lisovskiy@intel.com
parent 797e2c3f

drivers/gpu/drm/i915/display/intel_dp_mst.c

+14 −2
Original line number Diff line number Diff line
@@ -59,6 +59,7 @@ static int intel_dp_mst_compute_link_config(struct intel_encoder *encoder, 
		&crtc_state->hw.adjusted_mode;

	bool constant_n = drm_dp_has_quirk(&intel_dp->desc, DP_DPCD_QUIRK_CONSTANT_N);

	int bpp, slots = -EINVAL;

	int ret = 0;



	crtc_state->lane_count = limits->max_lane_count;

	crtc_state->port_clock = limits->max_rate;
@@ -78,9 +79,20 @@ static int intel_dp_mst_compute_link_config(struct intel_encoder *encoder, 
									       crtc_state->lane_count));

		if (slots == -EDEADLK)

			return slots;

		if (slots >= 0)

		if (slots >= 0) {

			ret = drm_dp_mst_atomic_check(state);

			/*

			 * If we got slots >= 0 and we can fit those based on check

			 * then we can exit the loop. Otherwise keep trying.

			 */

			if (!ret)

				break;

		}

	}



	/* Despite slots are non-zero, we still failed the atomic check */

	if (ret && slots >= 0)

		slots = ret;



	if (slots < 0) {

		drm_dbg_kms(&i915->drm, "failed finding vcpi slots:%d\n",