From a89bd7beb1791ad5ed634989b14c764114a68e53 Mon Sep 17 00:00:00 2001
From: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date: Tue, 7 Jun 2016 17:19:19 +0300
Subject: [PATCH] drm/i915/gen9: Add WaFbcHighMemBwCorruptionAvoidance
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

Add this fbc related workaround for all gen9

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1465309159-30531-28-git-send-email-mika.kuoppala@intel.com
(cherry picked from commit d1b4eefdea6d63aa15321f539feec298d8aefdc1)
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
---
 drivers/gpu/drm/i915/i915_reg.h | 1 +
 drivers/gpu/drm/i915/intel_pm.c | 4 ++++
 2 files changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 3b374284f7394..b2fbbfa07edaa 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -2206,6 +2206,7 @@ enum skl_disp_power_wells {
 #define ILK_DPFC_STATUS		_MMIO(0x43210)
 #define ILK_DPFC_FENCE_YOFF	_MMIO(0x43218)
 #define ILK_DPFC_CHICKEN	_MMIO(0x43224)
+#define   ILK_DPFC_DISABLE_DUMMY0 (1<<8)
 #define   ILK_DPFC_NUKE_ON_ANY_MODIFICATION	(1<<23)
 #define ILK_FBC_RT_BASE		_MMIO(0x2128)
 #define   ILK_FBC_RT_VALID	(1<<0)
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 074d6a53cc3e3..2863b92c9da6d 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -74,6 +74,10 @@ static void gen9_init_clock_gating(struct drm_device *dev)
 	I915_WRITE(DISP_ARB_CTL, I915_READ(DISP_ARB_CTL) |
 		   DISP_FBC_WM_DIS |
 		   DISP_FBC_MEMORY_WAKE);
+
+	/* WaFbcHighMemBwCorruptionAvoidance:skl,bxt,kbl */
+	I915_WRITE(ILK_DPFC_CHICKEN, I915_READ(ILK_DPFC_CHICKEN) |
+		   ILK_DPFC_DISABLE_DUMMY0);
 }
 
 static void bxt_init_clock_gating(struct drm_device *dev)
-- 
2.30.2