On Tue, 2 Mar 2021 12:41:32 -0800 Manasi Navare manasi.d.navare@intel.com wrote:
In case of a modeset where a mode gets split across mutiple CRTCs in the driver specific implementation (bigjoiner in i915) we wrongly count the affected CRTCs based on the drm_crtc_mask and indicate the stolen CRTC as an affected CRTC in atomic_check_only(). This triggers a warning since affected CRTCs doent match requested CRTC.
To fix this in such bigjoiner configurations, we should only increment affected crtcs if that CRTC is enabled in UAPI not if it is just used internally in the driver to split the mode.
Hi,
I think that makes sense to me. Stealing CRTCs that are not currently used by the userspace (display server) should be ok, as long as that is completely invisible to userspace: meaning that it does not cause userspace to unexpectedly e.g. receive or miss per-crtc atomic completion events.
Can that also be asserted somehow, or does this already do that?
Thanks, pq
Cc: Ville Syrjälä ville.syrjala@linux.intel.com Cc: Simon Ser contact@emersion.fr Cc: Pekka Paalanen pekka.paalanen@collabora.co.uk Cc: Daniel Stone daniels@collabora.com Cc: Daniel Vetter daniel.vetter@intel.com Cc: dri-devel@lists.freedesktop.org Signed-off-by: Manasi Navare manasi.d.navare@intel.com
drivers/gpu/drm/drm_atomic.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c index 5b4547e0f775..d7acd6bbd97e 100644 --- a/drivers/gpu/drm/drm_atomic.c +++ b/drivers/gpu/drm/drm_atomic.c @@ -1358,8 +1358,10 @@ int drm_atomic_check_only(struct drm_atomic_state *state) } }
- for_each_new_crtc_in_state(state, crtc, new_crtc_state, i)
affected_crtc |= drm_crtc_mask(crtc);
for_each_new_crtc_in_state(state, crtc, new_crtc_state, i) {
if (new_crtc_state->enable)affected_crtc |= drm_crtc_mask(crtc);}
/*
- For commits that allow modesets drivers can add other CRTCs to the