[PATCH v2 9/9] drm/dp: Track MST link bandwidth

[Dhinakaran Pandiyan]

Use the added helpers to track MST link bandwidth for atomic modesets.
Link bw is acquired in the ->atomic_check() phase when CRTCs are being
enabled with drm_atomic_find_vcpi_slots() instead of drm_find_vcpi_slots().
Similarly, link bw is released during ->atomic_check() with the connector
helper callback ->atomic_release() when CRTCs are disabled.

Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
---
 drivers/gpu/drm/drm_atomic_helper.c |  9 ++++++++-
 drivers/gpu/drm/i915/intel_dp_mst.c | 13 ++++++++++++-
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index dd34d21..0d42173 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -385,8 +385,15 @@ mode_fixup(struct drm_atomic_state *state)
 
 		WARN_ON(!!conn_state->best_encoder != !!conn_state->crtc);
 
-		if (!conn_state->crtc || !conn_state->best_encoder)
+		if (!conn_state->crtc || !conn_state->best_encoder) {
+			const struct drm_connector_helper_funcs *conn_funcs;
+
+			conn_funcs = connector->helper_private;
+			if (conn_funcs->atomic_release)
+				conn_funcs->atomic_release(connector,
+							   conn_state);
 			continue;
+		}
 
 		crtc_state = drm_atomic_get_existing_crtc_state(state,
 								conn_state->crtc);
diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c b/drivers/gpu/drm/i915/intel_dp_mst.c
index 2f57a56..ee5fedb 100644
--- a/drivers/gpu/drm/i915/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/intel_dp_mst.c
@@ -44,6 +44,7 @@ static bool intel_dp_mst_compute_config(struct intel_encoder *encoder,
 	int lane_count, slots;
 	const struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
 	int mst_pbn;
+	struct drm_dp_mst_topology_state *topology_state;
 
 	pipe_config->has_pch_encoder = false;
 	bpp = 24;
@@ -65,7 +66,17 @@ static bool intel_dp_mst_compute_config(struct intel_encoder *encoder,
 	mst_pbn = drm_dp_calc_pbn_mode(adjusted_mode->crtc_clock, bpp);
 
 	pipe_config->pbn = mst_pbn;
-	slots = drm_dp_find_vcpi_slots(&intel_dp->mst_mgr, mst_pbn);
+	topology_state = drm_atomic_get_mst_topology_state(state,
+							   &intel_dp->mst_mgr);
+	if (topology_state == NULL)
+		return false;
+
+	slots = drm_dp_atomic_find_vcpi_slots(topology_state, connector->port,
+					      mst_pbn);
+	if (slots < 0) {
+		DRM_DEBUG_KMS("not enough link bw for this mode\n");
+		return false;
+	}
 
 	intel_link_compute_m_n(bpp, lane_count,
 			       adjusted_mode->crtc_clock,
-- 
2.7.4