This just limits the BPC for MST connectors to a maximum of 8 from
nv50_mstc_get_modes(), instead of doing so during
nv50_msto_atomic_check(). This doesn't introduce any functional changes
yet (other then userspace now lying about the max bpc, but we can't
support that yet anyway so meh). But, we'll need this in a moment so
that we can share mode validation between SST and MST which will fix
some real world issues.
Signed-off-by: Lyude Paul <lyude@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
drivers/gpu/drm/nouveau/dispnv50/disp.c | 25 ++++++++++++++-----------
1 file changed, 14 insertions(+), 11 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c
index 32a1c4221f1e..766b8e80a8f5 100644
--- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
+++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
@@ -903,15 +903,9 @@ nv50_msto_atomic_check(struct drm_encoder *encoder,
if (!state->duplicated) {
const int clock = crtc_state->adjusted_mode.clock;
- /*
- * XXX: Since we don't use HDR in userspace quite yet, limit
- * the bpc to 8 to save bandwidth on the topology. In the
- * future, we'll want to properly fix this by dynamically
- * selecting the highest possible bpc that would fit in the
- * topology
- */
- asyh->or.bpc = min(connector->display_info.bpc, 8U);
- asyh->dp.pbn = drm_dp_calc_pbn_mode(clock, asyh->or.bpc * 3, false);
+ asyh->or.bpc = connector->display_info.bpc;
+ asyh->dp.pbn = drm_dp_calc_pbn_mode(clock, asyh->or.bpc * 3,
+ false);
}
slots = drm_dp_atomic_find_vcpi_slots(state, &mstm->mgr, mstc->port,
@@ -1071,8 +1065,17 @@ nv50_mstc_get_modes(struct drm_connector *connector)
if (mstc->edid)
ret = drm_add_edid_modes(&mstc->connector, mstc->edid);
- if (!mstc->connector.display_info.bpc)
- mstc->connector.display_info.bpc = 8;
+ /*
+ * XXX: Since we don't use HDR in userspace quite yet, limit the bpc
+ * to 8 to save bandwidth on the topology. In the future, we'll want
+ * to properly fix this by dynamically selecting the highest possible
+ * bpc that would fit in the topology
+ */
+ if (connector->display_info.bpc)
+ connector->display_info.bpc =
+ clamp(connector->display_info.bpc, 6U, 8U);
+ else
+ connector->display_info.bpc = 8;
if (mstc->native)
drm_mode_destroy(mstc->connector.dev, mstc->native);
--
2.24.1
