From e3a290553f3b09b657962e0a952fcf9b117bc08b Mon Sep 17 00:00:00 2001 From: Robert Beckett Date: Wed, 11 Mar 2015 10:28:25 +0200 Subject: [PATCH] drm/i915/bxt: add workaround to avoid PTE corruption Set TLBPF in TILECTL. This fixes an issue with BXT HW seeing corrupted pte entries. v2: - move the workaround to bxt_init_clock_gating (imre) Signed-off-by: Robert Beckett (v1) Signed-off-by: Imre Deak Reviewed-by: Nick Hoath Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_reg.h | 1 + drivers/gpu/drm/i915/intel_pm.c | 2 ++ 2 files changed, 3 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index a22745855740..21e69cab6efe 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -1150,6 +1150,7 @@ enum skl_disp_power_wells { /* control register for cpu gtt access */ #define TILECTL 0x101000 #define TILECTL_SWZCTL (1 << 0) +#define TILECTL_TLBPF (1 << 1) #define TILECTL_TLB_PREFETCH_DIS (1 << 2) #define TILECTL_BACKSNOOP_DIS (1 << 3) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 07b3780677c9..472463806759 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -110,6 +110,8 @@ static void bxt_init_clock_gating(struct drm_device *dev) GEN8_SDEUNIT_CLOCK_GATE_DISABLE | GEN8_HDCUNIT_CLOCK_GATE_DISABLE_HDCREQ); + /* FIXME: apply on A0 only */ + I915_WRITE(TILECTL, I915_READ(TILECTL) | TILECTL_TLBPF); } static void i915_pineview_get_mem_freq(struct drm_device *dev) -- 2.34.1