If the atomic commit doesn't include any new plane, there is no need to choose a new CRTC for FBC, and the intel_fbc_choose_crtc() will bail out early. Although, if the FBC setup failed in the previous commit, if the current commit doesn't include new plane update, it tries to overwrite no_fbc_reason to "no suitable CRTC for FBC". For that scenario, it is better that we simply keep the old message in-place to make debugging easier. A scenario where this happens is with the igt@kms_frontbuffer_tracking@fbc-suspend testcase when executed on a Haswell system with not enough stolen memory. When enabling the CRTC, the FBC setup will be correctly initialized to a specific CRTC, but won't be enabled, since there is not enough memory. The testcase will then enable CRC checking, which requires a quirk for Haswell, which issues a new atomic commit that doesn't update the planes. Since that update doesn't include any new planes (and the FBC wasn't enabled), intel_fbc_choose_crtc() will not find any suitable CRTC, but update the error message, hiding the lack of memory information, which is the actual cause of the initialization failure. As a result, this causes that test, which should skip, to fail on Haswell. Changes since v1: - Update commit message (Manasi) Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100020 Fixes: f7e9b004b8a3 ("drm/i915/fbc: inline intel_fbc_can_choose()") Reported-by: Dorota Czaplejewicz <dorota.czaplejewicz@xxxxxxxxxxxxxxx> Signed-off-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxxxx> Cc: Paulo Zanoni <paulo.r.zanoni@xxxxxxxxx> --- drivers/gpu/drm/i915/intel_fbc.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_fbc.c b/drivers/gpu/drm/i915/intel_fbc.c index ded2add18b26..0c99c9b731ee 100644 --- a/drivers/gpu/drm/i915/intel_fbc.c +++ b/drivers/gpu/drm/i915/intel_fbc.c @@ -1045,6 +1045,7 @@ void intel_fbc_choose_crtc(struct drm_i915_private *dev_priv, struct drm_plane *plane; struct drm_plane_state *plane_state; bool crtc_chosen = false; + bool new_planes = false; int i; mutex_lock(&fbc->lock); @@ -1066,6 +1067,7 @@ void intel_fbc_choose_crtc(struct drm_i915_private *dev_priv, to_intel_plane_state(plane_state); struct intel_crtc_state *intel_crtc_state; struct intel_crtc *crtc = to_intel_crtc(plane_state->crtc); + new_planes = true; if (!intel_plane_state->base.visible) continue; @@ -1084,7 +1086,7 @@ void intel_fbc_choose_crtc(struct drm_i915_private *dev_priv, break; } - if (!crtc_chosen) + if (new_planes && !crtc_chosen) fbc->no_fbc_reason = "no suitable CRTC for FBC"; out: -- 2.11.0 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
