[PATCH 6/8] drm/i915/psr: Do not write registers/bits not applicable for panel replay

["Jouni Högander" <jouni.hogander@intel.com>]

Bspec is saying this
mask register: Only PSR_MASK[Mask FBC modify] and PSR_MASK[Mask Hotplug]
are used in panel replay mode.

Status register: Only SRD_STATUS[SRD state] field is used in panel replay
mode.

Due to this stop writing and reading registers and bits not used by panel
replay if panel replay is used.

Bspec: 53370, 68920

v2:
  - use intel_dp_is_edp with PSR_MASK register
  - handle LunarLake as well
  - hanle ALPM configuration as well

Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Reviewed-by: Animesh Manna <animesh.manna@intel.com>
---
 drivers/gpu/drm/i915/display/intel_psr.c | 70 +++++++++++++++---------
 1 file changed, 45 insertions(+), 25 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
index d7547eefc2fa..b7538a4405b8 100644
--- a/drivers/gpu/drm/i915/display/intel_psr.c
+++ b/drivers/gpu/drm/i915/display/intel_psr.c
@@ -346,6 +346,9 @@ static void psr_irq_control(struct intel_dp *intel_dp)
 	enum transcoder cpu_transcoder = intel_dp->psr.transcoder;
 	u32 mask;
 
+	if (intel_dp->psr.panel_replay_enabled)
+		return;
+
 	mask = psr_irq_psr_error_bit_get(intel_dp);
 	if (intel_dp->psr.debug & I915_PSR_DEBUG_IRQ)
 		mask |= psr_irq_post_exit_bit_get(intel_dp) |
@@ -1783,7 +1786,7 @@ static void intel_psr_enable_source(struct intel_dp *intel_dp,
 {
 	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
 	enum transcoder cpu_transcoder = intel_dp->psr.transcoder;
-	u32 mask;
+	u32 mask = 0;
 
 	/*
 	 * Only HSW and BDW have PSR AUX registers that need to be setup.
@@ -1797,34 +1800,46 @@ static void intel_psr_enable_source(struct intel_dp *intel_dp,
 	 * mask LPSP to avoid dependency on other drivers that might block
 	 * runtime_pm besides preventing  other hw tracking issues now we
 	 * can rely on frontbuffer tracking.
+	 *
+	 * From bspec prior LunarLake:
+	 * Only PSR_MASK[Mask FBC modify] and PSR_MASK[Mask Hotplug] are used in
+	 * panel replay mode.
+	 *
+	 * From bspec beyod LunarLake:
+	 * Panel Replay on DP: No bits are applicable
+	 * Panel Replay on eDP: All bits are applicable
 	 */
-	mask = EDP_PSR_DEBUG_MASK_MEMUP |
-	       EDP_PSR_DEBUG_MASK_HPD;
+	if (DISPLAY_VER(dev_priv) < 20 || intel_dp_is_edp(intel_dp))
+		mask = EDP_PSR_DEBUG_MASK_HPD;
 
-	/*
-	 * For some unknown reason on HSW non-ULT (or at least on
-	 * Dell Latitude E6540) external displays start to flicker
-	 * when PSR is enabled on the eDP. SR/PC6 residency is much
-	 * higher than should be possible with an external display.
-	 * As a workaround leave LPSP unmasked to prevent PSR entry
-	 * when external displays are active.
-	 */
-	if (DISPLAY_VER(dev_priv) >= 8 || IS_HASWELL_ULT(dev_priv))
-		mask |= EDP_PSR_DEBUG_MASK_LPSP;
+	if (intel_dp_is_edp(intel_dp)) {
+		mask |= EDP_PSR_DEBUG_MASK_MEMUP;
 
-	if (DISPLAY_VER(dev_priv) < 20)
-		mask |= EDP_PSR_DEBUG_MASK_MAX_SLEEP;
+		/*
+		 * For some unknown reason on HSW non-ULT (or at least on
+		 * Dell Latitude E6540) external displays start to flicker
+		 * when PSR is enabled on the eDP. SR/PC6 residency is much
+		 * higher than should be possible with an external display.
+		 * As a workaround leave LPSP unmasked to prevent PSR entry
+		 * when external displays are active.
+		 */
+		if (DISPLAY_VER(dev_priv) >= 8 || IS_HASWELL_ULT(dev_priv))
+			mask |= EDP_PSR_DEBUG_MASK_LPSP;
 
-	/*
-	 * No separate pipe reg write mask on hsw/bdw, so have to unmask all
-	 * registers in order to keep the CURSURFLIVE tricks working :(
-	 */
-	if (IS_DISPLAY_VER(dev_priv, 9, 10))
-		mask |= EDP_PSR_DEBUG_MASK_DISP_REG_WRITE;
+		if (DISPLAY_VER(dev_priv) < 20)
+			mask |= EDP_PSR_DEBUG_MASK_MAX_SLEEP;
 
-	/* allow PSR with sprite enabled */
-	if (IS_HASWELL(dev_priv))
-		mask |= EDP_PSR_DEBUG_MASK_SPRITE_ENABLE;
+		/*
+		 * No separate pipe reg write mask on hsw/bdw, so have to unmask all
+		 * registers in order to keep the CURSURFLIVE tricks working :(
+		 */
+		if (IS_DISPLAY_VER(dev_priv, 9, 10))
+			mask |= EDP_PSR_DEBUG_MASK_DISP_REG_WRITE;
+
+		/* allow PSR with sprite enabled */
+		if (IS_HASWELL(dev_priv))
+			mask |= EDP_PSR_DEBUG_MASK_SPRITE_ENABLE;
+	}
 
 	intel_de_write(dev_priv, psr_debug_reg(dev_priv, cpu_transcoder), mask);
 
@@ -1843,7 +1858,8 @@ static void intel_psr_enable_source(struct intel_dp *intel_dp,
 			     intel_dp->psr.psr2_sel_fetch_enabled ?
 			     IGNORE_PSR2_HW_TRACKING : 0);
 
-	lnl_alpm_configure(intel_dp);
+	if (intel_dp_is_edp(intel_dp))
+		lnl_alpm_configure(intel_dp);
 
 	/*
 	 * Wa_16013835468
@@ -1884,6 +1900,9 @@ static bool psr_interrupt_error_check(struct intel_dp *intel_dp)
 	enum transcoder cpu_transcoder = intel_dp->psr.transcoder;
 	u32 val;
 
+	if (intel_dp->psr.panel_replay_enabled)
+		goto no_err;
+
 	/*
 	 * If a PSR error happened and the driver is reloaded, the EDP_PSR_IIR
 	 * will still keep the error set even after the reset done in the
@@ -1901,6 +1920,7 @@ static bool psr_interrupt_error_check(struct intel_dp *intel_dp)
 		return false;
 	}
 
+no_err:
 	return true;
 }
 
-- 
2.34.1