[PATCH 5.4 086/214] drm/amd/display: Trigger modesets on MST DSC connectors

From: Greg Kroah-Hartman
Date: Tue Sep 01 2020 - 12:35:44 EST


From: Mikita Lipski <mikita.lipski@xxxxxxx>

[ Upstream commit 44be939ff7ac5858f0dbd8a2a4af1fe198e14db1 ]

Whenever a connector on an MST network is attached, detached, or
undergoes a modeset, the DSC configs for each stream on that
topology will be recalculated. This can change their required
bandwidth, requiring a full reprogramming, as though a modeset
was performed, even if that stream did not change timing.

Therefore, whenever a crtc has drm_atomic_crtc_needs_modeset,
for each crtc that shares a MST topology with that stream and
supports DSC, add that crtc (and all affected connectors and
planes) to the atomic state and set mode_changed on its state

v2: Do this check only on Navi and before adding connectors
and planes on modesetting crtcs

v3: Call the drm_dp_mst_add_affected_dsc_crtcs() to update
all affected CRTCs

Reviewed-by: Lyude Paul <lyude@xxxxxxxxxx>
Signed-off-by: David Francis <David.Francis@xxxxxxx>
Signed-off-by: Mikita Lipski <mikita.lipski@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
.../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 33 +++++++++++++++++++
1 file changed, 33 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 2c0eb7140ca0e..5bde49a13f8c7 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -7230,6 +7230,29 @@ dm_determine_update_type_for_commit(struct amdgpu_display_manager *dm,
return ret;
}

+static int add_affected_mst_dsc_crtcs(struct drm_atomic_state *state, struct drm_crtc *crtc)
+{
+ struct drm_connector *connector;
+ struct drm_connector_state *conn_state;
+ struct amdgpu_dm_connector *aconnector = NULL;
+ int i;
+ for_each_new_connector_in_state(state, connector, conn_state, i) {
+ if (conn_state->crtc != crtc)
+ continue;
+
+ aconnector = to_amdgpu_dm_connector(connector);
+ if (!aconnector->port || !aconnector->mst_port)
+ aconnector = NULL;
+ else
+ break;
+ }
+
+ if (!aconnector)
+ return 0;
+
+ return drm_dp_mst_add_affected_dsc_crtcs(state, &aconnector->mst_port->mst_mgr);
+}
+
/**
* amdgpu_dm_atomic_check() - Atomic check implementation for AMDgpu DM.
* @dev: The DRM device
@@ -7282,6 +7305,16 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
if (ret)
goto fail;

+ if (adev->asic_type >= CHIP_NAVI10) {
+ for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
+ if (drm_atomic_crtc_needs_modeset(new_crtc_state)) {
+ ret = add_affected_mst_dsc_crtcs(state, crtc);
+ if (ret)
+ goto fail;
+ }
+ }
+ }
+
for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
if (!drm_atomic_crtc_needs_modeset(new_crtc_state) &&
!new_crtc_state->color_mgmt_changed &&
--
2.25.1