[Intel-gfx] [PATCH V3] drm/i915/gen11: Disable cursor clock gating in HDR mode

[Tejas Upadhyay]

Display underrun in HDR mode when cursor is enabled.
RTL fix will be implemented CLKGATE_DIS_PSL_A bit 28-46520h.
As per W/A 1604331009, Disable cursor clock gating in HDR mode.

Bspec : 33451

Changes since V2:
        - Made it general gen11 WA
        - Removed WA needed check
        - Added cursor plane active check
        - Once WA enable, software will not disable
Changes since V1:
        - Modified way CLKGATE_DIS_PSL bit 28 was modified

Cc: Souza Jose <jose.souza at intel.com>
Signed-off-by: Tejas Upadhyay <tejaskumarx.surendrakumar.upadhyay at intel.com>
---
 drivers/gpu/drm/i915/display/intel_display.c | 15 +++++++++++++++
 drivers/gpu/drm/i915/i915_reg.h              |  5 +++++
 2 files changed, 20 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 6be1b31af07b..99b33455b945 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -383,6 +383,18 @@ icl_wa_scalerclkgating(struct drm_i915_private *dev_priv, enum pipe pipe,
 		               intel_de_read(dev_priv, CLKGATE_DIS_PSL(pipe)) & ~DPFR_GATING_DIS);
 }
 
+/* Wa_1604331009:icl,jsl,ehl */
+static void
+icl_wa_cursorclkgating(struct drm_i915_private *dev_priv, enum pipe pipe,
+		       const struct intel_crtc_state *crtc_state)
+{
+	if (crtc_state->active_planes & icl_hdr_plane_mask() &&
+	    crtc_state->active_planes & BIT(PLANE_CURSOR) &&
+	    IS_GEN(dev_priv, 11))
+		intel_de_rmw(dev_priv, CLKGATE_DIS_PSL(pipe),
+			     CURSOR_GATING_DIS, CURSOR_GATING_DIS);
+}
+
 static bool
 is_trans_port_sync_slave(const struct intel_crtc_state *crtc_state)
 {
@@ -2939,6 +2951,9 @@ static void intel_pre_plane_update(struct intel_atomic_state *state,
 	    needs_scalerclk_wa(new_crtc_state))
 		icl_wa_scalerclkgating(dev_priv, pipe, true);
 
+	/* Wa_1604331009:icl,jsl,ehl */
+	icl_wa_cursorclkgating(dev_priv, pipe, new_crtc_state);
+
 	/*
 	 * Vblank time updates from the shadow to live plane control register
 	 * are blocked if the memory self-refresh mode is active at that
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 955027799d1d..bbdd8429297d 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -4235,6 +4235,11 @@ enum {
 #define INF_UNIT_LEVEL_CLKGATE		_MMIO(0x9560)
 #define   CGPSF_CLKGATE_DIS		(1 << 3)
 
+/*
+ * GEN11 clock gating regs
+ */
+#define   CURSOR_GATING_DIS            BIT(28)
+
 /*
  * Display engine regs
  */
-- 
2.31.1