diff options
| author | Chris Wilson <chris@chris-wilson.co.uk> | 2012-07-02 11:51:03 -0300 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2012-07-03 22:09:21 +0200 |
| commit | c4de7b0ffda2bb4843fd7f1052d0a2bb90bd08a5 (patch) | |
| tree | b6806b54c43e44dd15e1bf7bf3480a4f47b8edcd /drivers/gpu/drm/i915/i915_drv.c | |
| parent | 990bbdadabaa51828e475eda86ee5720a4910cc3 (diff) | |
drm/i915: Implement w/a for sporadic read failures on waking from rc6
As a w/a to prevent reads sporadically returning 0, we need to wait for
the GT thread to return to TC0 before proceeding to read the registers.
v2: adapt for Haswell changes (Eugeni).
v3: use wait_for_atomic_us for thread status polling.
v3: *really* use wait_for_atomic for polling.
References: https://bugs.freedesktop.org/show_bug.cgi?id=50243
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Acked-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/gpu/drm/i915/i915_drv.c')
| -rw-r--r-- | drivers/gpu/drm/i915/i915_drv.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index 928b6677759d..a4ea4a9fc425 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -433,6 +433,22 @@ bool i915_semaphore_is_enabled(struct drm_device *dev) return 1; } +static void __gen6_gt_wait_for_thread_c0(struct drm_i915_private *dev_priv) +{ + u32 gt_thread_status_mask; + + if (IS_HASWELL(dev_priv->dev)) + gt_thread_status_mask = GEN6_GT_THREAD_STATUS_CORE_MASK_HSW; + else + gt_thread_status_mask = GEN6_GT_THREAD_STATUS_CORE_MASK; + + /* w/a for a sporadic read returning 0 by waiting for the GT + * thread to wake up. + */ + if (wait_for_atomic_us((I915_READ_NOTRACE(GEN6_GT_THREAD_STATUS_REG) & gt_thread_status_mask) == 0, 500)) + DRM_ERROR("GT thread status wait timed out\n"); +} + static void __gen6_gt_force_wake_get(struct drm_i915_private *dev_priv) { if (wait_for_atomic_us((I915_READ_NOTRACE(FORCEWAKE_ACK) & 1) == 0, 500)) @@ -442,6 +458,8 @@ static void __gen6_gt_force_wake_get(struct drm_i915_private *dev_priv) if (wait_for_atomic_us((I915_READ_NOTRACE(FORCEWAKE_ACK) & 1), 500)) DRM_ERROR("Force wake wait timed out\n"); + + __gen6_gt_wait_for_thread_c0(dev_priv); } static void __gen6_gt_force_wake_mt_get(struct drm_i915_private *dev_priv) @@ -453,6 +471,8 @@ static void __gen6_gt_force_wake_mt_get(struct drm_i915_private *dev_priv) if (wait_for_atomic_us((I915_READ_NOTRACE(FORCEWAKE_MT_ACK) & 1), 500)) DRM_ERROR("Force wake wait timed out\n"); + + __gen6_gt_wait_for_thread_c0(dev_priv); } /* @@ -538,6 +558,8 @@ static void vlv_force_wake_get(struct drm_i915_private *dev_priv) if (wait_for_atomic_us((I915_READ_NOTRACE(FORCEWAKE_ACK_VLV) & 1), 500)) DRM_ERROR("Force wake wait timed out\n"); + + __gen6_gt_wait_for_thread_c0(dev_priv); } static void vlv_force_wake_put(struct drm_i915_private *dev_priv) |