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@redhat.com Cc: stable@vger.kernel.org --- 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);