[Intel-gfx] [PATCH v4 11/18] drm/i915/display/vrr: Send VRR push to flip the frame

Manasi Navare manasi.d.navare at intel.com
Wed Jan 13 22:09:28 UTC 2021


VRR achieves vblank stretching using the HW PUSH functionality.
So once the VRR is enabled during modeset then for each flip
request from userspace, in the atomic tail pipe_update_end()
we need to set the VRR push bit in HW for it to terminate
the vblank at configured flipline or anytime after flipline
or latest at the Vmax.

The HW clears the PUSH bit after the double buffer updates
are completed.

v2:
* Move send push to after irq en (Manasi)
* Call send push unconditionally (Jani N)

v3:
* Stall w.r.t Vrr vmax (Manasi, Gary Smith)

v4:
* Remove the rmw (Ville)

Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Cc: Gary Smith <gary.k.smith at intel.com>
Signed-off-by: Manasi Navare <manasi.d.navare at intel.com>
---
 drivers/gpu/drm/i915/display/intel_sprite.c |  4 ++++
 drivers/gpu/drm/i915/display/intel_vrr.c    | 13 +++++++++++++
 drivers/gpu/drm/i915/display/intel_vrr.h    |  1 +
 3 files changed, 18 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_sprite.c b/drivers/gpu/drm/i915/display/intel_sprite.c
index ced6af7cdc84..0e82d1629d2d 100644
--- a/drivers/gpu/drm/i915/display/intel_sprite.c
+++ b/drivers/gpu/drm/i915/display/intel_sprite.c
@@ -50,6 +50,7 @@
 #include "intel_dsi.h"
 #include "intel_sprite.h"
 #include "i9xx_plane.h"
+#include "intel_vrr.h"
 
 int intel_usecs_to_scanlines(const struct drm_display_mode *adjusted_mode,
 			     int usecs)
@@ -266,6 +267,9 @@ void intel_pipe_update_end(struct intel_crtc_state *new_crtc_state)
 
 	local_irq_enable();
 
+	/* Send VRR Push to terminate Vblank */
+	intel_vrr_send_push(new_crtc_state);
+
 	if (intel_vgpu_active(dev_priv))
 		return;
 
diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c
index e7fb297e8d23..1b26806d3416 100644
--- a/drivers/gpu/drm/i915/display/intel_vrr.c
+++ b/drivers/gpu/drm/i915/display/intel_vrr.c
@@ -121,3 +121,16 @@ void intel_vrr_enable(struct intel_encoder *encoder,
 	intel_de_write(dev_priv, TRANS_VRR_FLIPLINE(cpu_transcoder), crtc_state->vrr.flipline - 1);
 	intel_de_write(dev_priv, TRANS_PUSH(cpu_transcoder), TRANS_PUSH_EN);
 }
+
+void intel_vrr_send_push(const struct intel_crtc_state *crtc_state)
+{
+	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
+	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
+
+	if (!crtc_state->vrr.enable)
+		return;
+
+	intel_de_write(dev_priv, TRANS_PUSH(cpu_transcoder),
+		       TRANS_PUSH_EN | TRANS_PUSH_SEND);
+}
diff --git a/drivers/gpu/drm/i915/display/intel_vrr.h b/drivers/gpu/drm/i915/display/intel_vrr.h
index 80c33fbd0639..1b7c53b5604a 100644
--- a/drivers/gpu/drm/i915/display/intel_vrr.h
+++ b/drivers/gpu/drm/i915/display/intel_vrr.h
@@ -22,5 +22,6 @@ void intel_vrr_compute_config(struct intel_crtc_state *crtc_state,
 			      struct drm_connector_state *conn_state);
 void intel_vrr_enable(struct intel_encoder *encoder,
 		      const struct intel_crtc_state *crtc_state);
+void intel_vrr_send_push(const struct intel_crtc_state *crtc_state);
 
 #endif /* __INTEL_VRR_H__ */
-- 
2.19.1



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