[PATCH 1/4] drm/i915/display: Do atomic commits from front buffer modifications

[José Roberto de Souza]

PSR2 selective fetch requires plane and transcoder of registers to
be programed during the vblank to properly update the display and
there is no way around it.

We could disable PSR2 at every notification of dirty front buffer from
user space but that would hurt the power savings and it would still
cause some race conditions between PSR2 exit sequence and atomic
commits that causes underruns and glitches.

So from display 12 and newer we will start to do atomic commits
every time user space notify that front buffer is dirty and ignore
all frontbuffer flushes and invalidates on the PSR side.

Cc: Daniel Vetter <daniel at ffwll.ch>
Cc: Gwan-gyeong Mun <gwan-gyeong.mun at intel.com>
Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
---
 drivers/gpu/drm/i915/display/intel_display.c | 7 ++++++-
 drivers/gpu/drm/i915/display/intel_psr.c     | 6 ++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 97a216edf600e..3752b60e5c141 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -11676,10 +11676,15 @@ static int intel_user_framebuffer_dirty(struct drm_framebuffer *fb,
 					unsigned num_clips)
 {
 	struct drm_i915_gem_object *obj = intel_fb_obj(fb);
+	struct drm_i915_private *i915 = to_i915(obj->base.dev);
 
 	i915_gem_object_flush_if_display(obj);
-	intel_frontbuffer_flush(to_intel_frontbuffer(fb), ORIGIN_DIRTYFB);
 
+	if (DISPLAY_VER(i915) >= 12)
+		return drm_atomic_helper_dirtyfb(fb, file, flags, color, clips,
+						 num_clips);
+
+	intel_frontbuffer_flush(to_intel_frontbuffer(fb), ORIGIN_DIRTYFB);
 	return 0;
 }
 
diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
index 9393b35cd4449..426120ae9cfb9 100644
--- a/drivers/gpu/drm/i915/display/intel_psr.c
+++ b/drivers/gpu/drm/i915/display/intel_psr.c
@@ -2032,6 +2032,9 @@ void intel_psr_invalidate(struct drm_i915_private *dev_priv,
 {
 	struct intel_encoder *encoder;
 
+	if (DISPLAY_VER(dev_priv) >= 12)
+		return;
+
 	if (origin == ORIGIN_FLIP)
 		return;
 
@@ -2116,6 +2119,9 @@ void intel_psr_flush(struct drm_i915_private *dev_priv,
 			continue;
 		}
 
+		if (DISPLAY_VER(dev_priv) >= 12)
+			continue;
+
 		mutex_lock(&intel_dp->psr.lock);
 		if (!intel_dp->psr.enabled) {
 			mutex_unlock(&intel_dp->psr.lock);
-- 
2.32.0