drm/i915/vrr: Prepare to Use TRANS_PUSH mechanism for PSR frame change

On Lunarlake and onward it is possible to generate PSR Frame Change
event using TRANS_PUSH mechanism:

Ensure push is performed on flip if needed by PSR.

Don't use intel_psr_trigger_frame_change_event if PSR uses trans push as
Frame Change event: When not using trans push to generate Frame Change
event plane/pipe register writes are triggering the event. This is causing
problems when transiting to PSR active/idle and the event is coming in. To
tackle this we are waiting PSR to idle and using
intel_psr_trigger_frame_change_event to ensure PSR exit. If the Frame
change event is triggered after everything is configured (on trans push) we
don't need to worry about all this.

Ensure possible intel_vrr_tg_disable call is not overwriting
LNL_TRANS_PUSH_PSR_PR_EN.

v8:
  - split adding intel_vrr_psr_frame_change_enable as a separate change
  - update commit message
v7:
  - HAS_PSR_FRAME_CHANGE macro moved to separate patch and renamed as
    HAS_PSR_TRANS_PUSH_FRAME_CHANGE
  - use intel_psr_use_trans_push instead of HAS_PSR_FRAME_CHANGE in
    intel_psr_trigger_frame_change
  - moved calling intel_vrr_psr_frame_change_enable away from this patch
v6:
  - add HAS_PSR_FRAME_CHANGE macro
  - use TRANS_PUSH in instead of TRAN_VRR_CTL
v5: use intel_psr_use_trans_push for intel_vrr_psr_frame_change_enable
v4:
  - use rmw when enabling/disabling transcoder
  - set TRANS_PUSH_EN conditionally in intel_vrr_send_push
  - do not call intel_vrr_send_push from intel_psr_trigger_frame_change
  - do not enable using TRANS_PUSH mechanism for PSR "Frame Change"
v3:
  - use rmw when enabling/disabling
  - keep LNL_TRANS_PUSH_PSR_PR_EN set always on LunarLake and onwards
v2: use intel_vrr_trans_push_enabled_set_clear instead of rmw

Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://patch.msgid.link/20260127124120.1069026-6-jouni.hogander@intel.com

3 files changed, 11 insertions, 6 deletions

diff --git a/drivers/gpu/drm/i915/display/intel_crtc.c b/drivers/gpu/drm/i915/display/intel_crtc.c
index 778ebc5095c3..ed3c6c4ce025 100644
--- a/drivers/gpu/drm/i915/display/intel_crtc.c
+++ b/drivers/gpu/drm/i915/display/intel_crtc.c
@@ -747,7 +747,9 @@ void intel_pipe_update_end(struct intel_atomic_state *state,
 	 * which would cause the next frame to terminate already at vmin
 	 * vblank start instead of vmax vblank start.
 	 */
-	if (!state->base.legacy_cursor_update)
+	if (!state->base.legacy_cursor_update ||
+	    (intel_psr_use_trans_push(new_crtc_state) &&
+	     !new_crtc_state->vrr.enable))
 		intel_vrr_send_push(NULL, new_crtc_state);
 
 	local_irq_enable();
diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
index b0d72c04db45..9613c50623dc 100644
--- a/drivers/gpu/drm/i915/display/intel_psr.c
+++ b/drivers/gpu/drm/i915/display/intel_psr.c
@@ -2516,9 +2516,11 @@ void intel_psr_trigger_frame_change_event(struct intel_dsb *dsb,
 		intel_pre_commit_crtc_state(state, crtc);
 	struct intel_display *display = to_intel_display(crtc);
 
-	if (crtc_state->has_psr)
-		intel_de_write_dsb(display, dsb,
-				   CURSURFLIVE(display, crtc->pipe), 0);
+	if (!crtc_state->has_psr || intel_psr_use_trans_push(crtc_state))
+		return;
+
+	intel_de_write_dsb(display, dsb,
+			   CURSURFLIVE(display, crtc->pipe), 0);
 }
 
 /**
diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c
index 66c68e7f3a49..8a072f90049f 100644
--- a/drivers/gpu/drm/i915/display/intel_vrr.c
+++ b/drivers/gpu/drm/i915/display/intel_vrr.c
@@ -698,7 +698,7 @@ void intel_vrr_send_push(struct intel_dsb *dsb,
 	struct intel_display *display = to_intel_display(crtc_state);
 	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
 
-	if (!crtc_state->vrr.enable)
+	if (!crtc_state->vrr.enable && !intel_psr_use_trans_push(crtc_state))
 		return;
 
 	if (dsb)
@@ -920,7 +920,8 @@ static void intel_vrr_tg_disable(const struct intel_crtc_state *old_crtc_state)
 				       VRR_STATUS_VRR_EN_LIVE, 1000))
 		drm_err(display->drm, "Timed out waiting for VRR live status to clear\n");
 
-	intel_de_write(display, TRANS_PUSH(display, cpu_transcoder), 0);
+	intel_de_rmw(display, TRANS_PUSH(display, cpu_transcoder),
+		     TRANS_PUSH_EN, 0);
 }
 
 void intel_vrr_enable(const struct intel_crtc_state *crtc_state)