From 9cc19733fd7c83ac0577f2b80121dae3c289351b Mon Sep 17 00:00:00 2001 From: Robert Bragg Date: Sun, 12 Feb 2017 13:32:52 +0000 Subject: [PATCH] drm/i915: fix for WaDisableDopClockGating:bdw MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit This workaround for BDW was incomplete as it also requires EUTC clock gating to be disabled via UCGCTL1. v2: read modify write UCGTL1 in broadwell_init_clock_gating (Ville) Signed-off-by: Robert Bragg Cc: Ville Syrjälä Link: http://patchwork.freedesktop.org/patch/msgid/20170212133252.20990-1-robert@sixbynine.org Reviewed-by: Ville Syrjälä Signed-off-by: Ville Syrjälä --- drivers/gpu/drm/i915/intel_pm.c | 8 ++++++++ drivers/gpu/drm/i915/intel_ringbuffer.c | 6 +++++- 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index c0b0f5a..3c13be8 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -7229,6 +7229,14 @@ static void broadwell_init_clock_gating(struct drm_i915_private *dev_priv) | KVM_CONFIG_CHANGE_NOTIFICATION_SELECT); lpt_init_clock_gating(dev_priv); + + /* WaDisableDopClockGating:bdw + * + * Also see the CHICKEN2 write in bdw_init_workarounds() to disable DOP + * clock gating. + */ + I915_WRITE(GEN6_UCGCTL1, + I915_READ(GEN6_UCGCTL1) | GEN6_EU_TCUNIT_CLOCK_GATE_DISABLE); } static void haswell_init_clock_gating(struct drm_i915_private *dev_priv) diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 0b9030c..95906c4 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -812,7 +812,11 @@ static int bdw_init_workarounds(struct intel_engine_cs *engine) /* WaDisableThreadStallDopClockGating:bdw (pre-production) */ WA_SET_BIT_MASKED(GEN8_ROW_CHICKEN, STALL_DOP_GATING_DISABLE); - /* WaDisableDopClockGating:bdw */ + /* WaDisableDopClockGating:bdw + * + * Also see the related UCGTCL1 write in broadwell_init_clock_gating() + * to disable EUTC clock gating. + */ WA_SET_BIT_MASKED(GEN7_ROW_CHICKEN2, DOP_CLOCK_GATING_DISABLE); -- 2.7.4