[Intel-gfx] [PATCH 56/62] drm/i915/bdw: Implement edp PSR workarounds

[Ben Widawsky]

This implements a workaround for PSR dealing with some vblank issue.

WaPsrDPAMaskVBlankInSRD && WaPsrDPRSUnmaskVBlankInSRD

v2: forgot to git add bogus whitespace fix

v3: Update with workaround names.
Use for_each_pipe() and CHICKEN_PIPESL_1(pipe) macro (Ville)

Cc: Art Runyan <arthur.j.runyan at intel.com>
Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
---
 drivers/gpu/drm/i915/i915_reg.h |  6 ++++++
 drivers/gpu/drm/i915/intel_pm.c | 17 +++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index f97836e..9608f96 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -4092,8 +4092,14 @@
 # define CHICKEN3_DGMG_DONE_FIX_DISABLE		(1 << 2)
 
 #define CHICKEN_PAR1_1		0x42080
+#define  DPA_MASK_VBLANK_SRD	(1 << 15)
 #define  FORCE_ARB_IDLE_PLANES	(1 << 14)
 
+#define _CHICKEN_PIPESL_1_A	0x420b0
+#define _CHICKEN_PIPESL_1_B	0x420b4
+#define  DPRS_MASK_VBLANK_SRD	(1 << 0)
+#define CHICKEN_PIPESL_1(pipe) _PIPE(pipe, _CHICKEN_PIPESL_1_A, _CHICKEN_PIPESL_1_B)
+
 #define DISP_ARB_CTL	0x45000
 #define  DISP_TILE_SURFACE_SWIZZLING	(1<<13)
 #define  DISP_FBC_WM_DIS		(1<<15)
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 0245985..63f6e59 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -5288,6 +5288,23 @@ static void gen8_init_clock_gating(struct drm_device *dev)
 
 	/* WaSwitchSolVfFArbitrationPriority */
 	I915_WRITE(GAM_ECOCHK, I915_READ(GAM_ECOCHK) | HSW_ECOCHK_ARB_PRIO_SOL);
+
+	if (IS_BROADWELL(dev)) {
+		enum pipe i;
+
+		/* WaPsrDPAMaskVBlankInSRD */
+		I915_WRITE(CHICKEN_PAR1_1,
+			   I915_READ(CHICKEN_PAR1_1) | DPA_MASK_VBLANK_SRD);
+
+		/* WaPsrDPRSUnmaskVBlankInSRD */
+		for_each_pipe(i) {
+			I915_WRITE(CHICKEN_PIPESL_1(i),
+				   I915_READ(CHICKEN_PIPESL_1(i) |
+					     DPRS_MASK_VBLANK_SRD));
+		}
+	}
+
+
 }
 
 static void haswell_init_clock_gating(struct drm_device *dev)
-- 
1.8.4.2