From: Ben Skeggs bskeggs@redhat.com

[ Upstream commit a0b694d0af21c9993d1a39a75fd814bd48bf7eb4 ]

HW has error checks in place which check that pixel depth is explicitly provided on DP, while HDMI has a "default" setting that we use.

In multi-display configurations with identical modelines, but different protocols (HDMI + DP, in this case), it was possible for the DP head to get swapped to the head which previously drove the HDMI output, without updating HeadSetControlOutputResource(), triggering the error check and hanging the core update.

Reported-by: Lyude Paul lyude@redhat.com Signed-off-by: Ben Skeggs bskeggs@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/nouveau/dispnv50/head.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/nouveau/dispnv50/head.c b/drivers/gpu/drm/nouveau/dispnv50/head.c index 4f57e53797968..d81a99bb2ac31 100644 --- a/drivers/gpu/drm/nouveau/dispnv50/head.c +++ b/drivers/gpu/drm/nouveau/dispnv50/head.c @@ -306,7 +306,7 @@ nv50_head_atomic_check(struct drm_crtc *crtc, struct drm_crtc_state *state) asyh->set.or = head->func->or != NULL; }

- if (asyh->state.mode_changed) + if (asyh->state.mode_changed || asyh->state.connectors_changed) nv50_head_atomic_check_mode(head, asyh);

if (asyh->state.color_mgmt_changed ||