[Intel-gfx] [PATCH V5] 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 V4:
	- Added WA needed check - Ville
	- Replace BIT with REG_BIT - Ville
	- Add WA enable/disable support back which was added in V1 - Ville
Changes since V3:
        - Disable WA when not in HDR mode or cursor plane not active - Ville
        - Extract required args from crtc_state - Ville
        - Create HDR mode API using bdw_set_pipemisc ref - Ville
        - Tested with HDR video as well full setmode, WA applies and disables
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

Signed-off-by: Tejas Upadhyay <tejaskumarx.surendrakumar.upadhyay at intel.com>
---
 drivers/gpu/drm/i915/display/intel_display.c | 36 ++++++++++++++++++++
 drivers/gpu/drm/i915/i915_reg.h              |  1 +
 2 files changed, 37 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index f27c294beb92..fef3e182c5e7 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -214,6 +214,19 @@ 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,
+		       bool enable)
+{
+	if (enable)
+		intel_de_write(dev_priv, CLKGATE_DIS_PSL(pipe),
+			       intel_de_read(dev_priv, CLKGATE_DIS_PSL(pipe)) | CURSOR_GATING_DIS);
+	else
+		intel_de_write(dev_priv, CLKGATE_DIS_PSL(pipe),
+			       intel_de_read(dev_priv, CLKGATE_DIS_PSL(pipe)) & ~CURSOR_GATING_DIS);
+}
+
 static bool
 is_trans_port_sync_slave(const struct intel_crtc_state *crtc_state)
 {
@@ -2356,6 +2369,19 @@ static bool needs_scalerclk_wa(const struct intel_crtc_state *crtc_state)
 	return false;
 }
 
+static bool needs_cursorclk_wa(const struct intel_crtc_state *crtc_state)
+{
+	struct drm_i915_private *dev_priv = to_i915(crtc_state->uapi.crtc->dev);
+
+	/* Wa_1604331009:icl,jsl,ehl */
+	if (is_hdr_mode(crtc_state) &&
+	    crtc_state->active_planes & BIT(PLANE_CURSOR) &&
+	    DISPLAY_VER(dev_priv) == 11)
+		return true;
+
+	return false;
+}
+
 static bool planes_enabling(const struct intel_crtc_state *old_crtc_state,
 			    const struct intel_crtc_state *new_crtc_state)
 {
@@ -2398,6 +2424,11 @@ static void intel_post_plane_update(struct intel_atomic_state *state,
 	if (needs_scalerclk_wa(old_crtc_state) &&
 	    !needs_scalerclk_wa(new_crtc_state))
 		icl_wa_scalerclkgating(dev_priv, pipe, false);
+
+	if (needs_cursorclk_wa(old_crtc_state) &&
+	    !needs_cursorclk_wa(new_crtc_state))
+		icl_wa_cursorclkgating(dev_priv, pipe, false);
+
 }
 
 static void intel_crtc_enable_flip_done(struct intel_atomic_state *state,
@@ -2494,6 +2525,11 @@ 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 */
+	if (!needs_cursorclk_wa(old_crtc_state) &&
+	    needs_cursorclk_wa(new_crtc_state))
+		icl_wa_cursorclkgating(dev_priv, pipe, true);
+
 	/*
 	 * 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 ef594df039db..7b3eed5b4e42 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -4272,6 +4272,7 @@ enum {
 #define   DPF_GATING_DIS		(1 << 10)
 #define   DPF_RAM_GATING_DIS		(1 << 9)
 #define   DPFR_GATING_DIS		(1 << 8)
+#define   CURSOR_GATING_DIS		REG_BIT(28)
 
 #define CLKGATE_DIS_PSL(pipe) \
 	_MMIO_PIPE(pipe, _CLKGATE_DIS_PSL_A, _CLKGATE_DIS_PSL_B)
-- 
2.31.1