[PATCH v3 4/4] drm/i915/vrr: Use TRANS_PUSH mechanism for PSR frame change

[Jouni Högander]

On Lunarlake and onwards it is possible to generate "PSR frame change"
event using TRANS_PUSH mechanism. Implement function to enable this and
take PSR into account in intel_vrr_send_push. Also use
intel_vrr_send_push in intel_psr_trigger_frame_change_event.

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 at intel.com>
---
 drivers/gpu/drm/i915/display/intel_psr.c | 10 +++++++
 drivers/gpu/drm/i915/display/intel_vrr.c | 33 +++++++++++++++++-------
 drivers/gpu/drm/i915/display/intel_vrr.h |  1 +
 3 files changed, 35 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
index 3d637d92ca89..5ba46f808c1a 100644
--- a/drivers/gpu/drm/i915/display/intel_psr.c
+++ b/drivers/gpu/drm/i915/display/intel_psr.c
@@ -1966,6 +1966,9 @@ static void intel_psr_enable_source(struct intel_dp *intel_dp,
 		intel_dmc_block_pkgc(display, intel_dp->psr.pipe, true);
 
 	intel_alpm_configure(intel_dp, crtc_state);
+
+	if (DISPLAY_VER(display) >= 20)
+		intel_vrr_psr_frame_change_enable(crtc_state);
 }
 
 static bool psr_interrupt_error_check(struct intel_dp *intel_dp)
@@ -2350,11 +2353,18 @@ void intel_psr_trigger_frame_change_event(struct intel_dsb *dsb,
 {
 	const struct intel_crtc_state *crtc_state =
 		intel_pre_commit_crtc_state(state, crtc);
+	const struct intel_crtc_state *new_crtc_state =
+		intel_atomic_get_new_crtc_state(state, crtc);
 	struct intel_display *display = to_intel_display(crtc);
 
 	if (crtc_state->has_psr)
+		return;
+
+	if (DISPLAY_VER(display) < 20)
 		intel_de_write_dsb(display, dsb,
 				   CURSURFLIVE(display, crtc->pipe), 0);
+	else
+		intel_vrr_send_push(dsb, new_crtc_state);
 }
 
 /**
diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c
index c55b8144e234..4120e58de35a 100644
--- a/drivers/gpu/drm/i915/display/intel_vrr.c
+++ b/drivers/gpu/drm/i915/display/intel_vrr.c
@@ -505,16 +505,22 @@ 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;
+	u32 trans_push;
 
-	if (!crtc_state->vrr.enable)
+	if (!crtc_state->vrr.enable && (DISPLAY_VER(display) < 20 ||
+					!crtc_state->has_psr))
 		return;
 
 	if (dsb)
 		intel_dsb_nonpost_start(dsb);
 
-	intel_de_write_dsb(display, dsb,
-			   TRANS_PUSH(display, cpu_transcoder),
-			   TRANS_PUSH_EN | TRANS_PUSH_SEND);
+	trans_push = TRANS_PUSH_EN | TRANS_PUSH_SEND;
+
+	if (DISPLAY_VER(display) >= 20 && crtc_state->has_psr)
+		trans_push |= LNL_TRANS_PUSH_PSR_PR_EN;
+
+	intel_de_write_dsb(display, dsb, TRANS_PUSH(display, cpu_transcoder),
+			   trans_push);
 
 	if (dsb)
 		intel_dsb_nonpost_end(dsb);
@@ -559,7 +565,8 @@ bool intel_vrr_is_push_sent(const struct intel_crtc_state *crtc_state)
 	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 && (DISPLAY_VER(display) < 20 ||
+					!crtc_state->has_psr))
 		return false;
 
 	return intel_de_read(display, TRANS_PUSH(display, cpu_transcoder)) & TRANS_PUSH_SEND;
@@ -609,9 +616,7 @@ void intel_vrr_enable(const struct intel_crtc_state *crtc_state)
 		       crtc_state->vrr.vmax - 1);
 	intel_de_write(display, TRANS_VRR_FLIPLINE(display, cpu_transcoder),
 		       crtc_state->vrr.flipline - 1);
-
-	intel_de_write(display, TRANS_PUSH(display, cpu_transcoder),
-		       TRANS_PUSH_EN);
+	intel_de_rmw(display, TRANS_PUSH(display, cpu_transcoder), 0, TRANS_PUSH_EN);
 
 	if (!intel_vrr_always_use_vrr_tg(display)) {
 		intel_vrr_set_db_point_and_transmission_line(crtc_state);
@@ -627,6 +632,15 @@ void intel_vrr_enable(const struct intel_crtc_state *crtc_state)
 	}
 }
 
+void intel_vrr_psr_frame_change_enable(const struct intel_crtc_state *crtc_state)
+{
+	struct intel_display *display = to_intel_display(crtc_state);
+	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
+
+	intel_de_rmw(display, TRANS_VRR_CTL(display, cpu_transcoder), 0,
+		     LNL_TRANS_PUSH_PSR_PR_EN);
+}
+
 void intel_vrr_disable(const struct intel_crtc_state *old_crtc_state)
 {
 	struct intel_display *display = to_intel_display(old_crtc_state);
@@ -641,7 +655,8 @@ void intel_vrr_disable(const struct intel_crtc_state *old_crtc_state)
 		intel_de_wait_for_clear(display,
 					TRANS_VRR_STATUS(display, cpu_transcoder),
 					VRR_STATUS_VRR_EN_LIVE, 1000);
-		intel_de_write(display, TRANS_PUSH(display, cpu_transcoder), 0);
+		intel_de_rmw(display, TRANS_PUSH(display, cpu_transcoder),
+			     TRANS_PUSH_EN, 0);
 	}
 
 	intel_vrr_set_fixed_rr_timings(old_crtc_state);
diff --git a/drivers/gpu/drm/i915/display/intel_vrr.h b/drivers/gpu/drm/i915/display/intel_vrr.h
index 38bf9996b883..6f815fd05c36 100644
--- a/drivers/gpu/drm/i915/display/intel_vrr.h
+++ b/drivers/gpu/drm/i915/display/intel_vrr.h
@@ -30,6 +30,7 @@ void intel_vrr_check_push_sent(struct intel_dsb *dsb,
 			       const struct intel_crtc_state *crtc_state);
 bool intel_vrr_is_push_sent(const struct intel_crtc_state *crtc_state);
 void intel_vrr_disable(const struct intel_crtc_state *old_crtc_state);
+void intel_vrr_psr_frame_change_enable(const struct intel_crtc_state *crtc_state);
 void intel_vrr_get_config(struct intel_crtc_state *crtc_state);
 int intel_vrr_vmax_vtotal(const struct intel_crtc_state *crtc_state);
 int intel_vrr_vmin_vtotal(const struct intel_crtc_state *crtc_state);
-- 
2.43.0