[PATCH 26/27] drm/i195/fbc: Add WaFbcNukeOnHostModify

Mika Kuoppala
2016-06-07T14:22:30Z

Bspec states that we need to set nuke on modify all to prevent
screen corruption with fbc on skl and kbl.

v2: proper workaround name

References: HSD#2227109, HSDES#1404569388
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>
---
drivers/gpu/drm/i915/i915_reg.h | 1 +
drivers/gpu/drm/i915/intel_pm.c | 8 ++++++++
2 files changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 9206fdc3113b..f6a140b2c77c 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -2209,6 +2209,7 @@ 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_NUKE_ON_ANY_MODIFICATION (1<<23)
#define ILK_FBC_RT_BASE _MMIO(0x2128)
#define ILK_FBC_RT_VALID (1<<0)
#define SNB_FBC_FRONT_BUFFER (1<<1)
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 8df9b5288679..1464d7ba69d4 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -6998,6 +6998,10 @@ static void kabylake_init_clock_gating(struct drm_device *dev)
if (IS_KBL_REVID(dev_priv, 0, KBL_REVID_B0))
I915_WRITE(GEN6_UCGCTL1, I915_READ(GEN6_UCGCTL1) |
GEN6_GAMUNIT_CLOCK_GATE_DISABLE);
+
+ /* WaFbcNukeOnHostModify:kbl */
+ I915_WRITE(ILK_DPFC_CHICKEN, I915_READ(ILK_DPFC_CHICKEN) |
+ ILK_DPFC_NUKE_ON_ANY_MODIFICATION);
}

static void skylake_init_clock_gating(struct drm_device *dev)
@@ -7009,6 +7013,10 @@ static void skylake_init_clock_gating(struct drm_device *dev)
/* WAC6entrylatency:skl */
I915_WRITE(FBC_LLC_READ_CTRL, I915_READ(FBC_LLC_READ_CTRL) |
FBC_LLC_FULLY_OPEN);
+
+ /* WaFbcNukeOnHostModify:skl */
+ I915_WRITE(ILK_DPFC_CHICKEN, I915_READ(ILK_DPFC_CHICKEN) |
+ ILK_DPFC_NUKE_ON_ANY_MODIFICATION);
}

static void broadwell_init_clock_gating(struct drm_device *dev)