diff options
| -rw-r--r-- | drivers/gpu/drm/i915/intel_ringbuffer.c | 32 |
1 files changed, 24 insertions, 8 deletions
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 9033697783b9..f5d6151c953f 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -180,14 +180,30 @@ static int init_ring_common(struct intel_ring_buffer *ring) if ((I915_READ_CTL(ring) & RING_VALID) == 0 || I915_READ_START(ring) != obj_priv->gtt_offset || (I915_READ_HEAD(ring) & HEAD_ADDR) != 0) { - DRM_ERROR("%s initialization failed " - "ctl %08x head %08x tail %08x start %08x\n", - ring->name, - I915_READ_CTL(ring), - I915_READ_HEAD(ring), - I915_READ_TAIL(ring), - I915_READ_START(ring)); - return -EIO; + if (IS_GEN6(ring->dev) && ring->dev->pdev->revision <= 8) { + /* Early revisions of Sandybridge do not like + * revealing the contents of the ring buffer + * registers whilst idle. Fortunately, the + * auto-reporting mechanism prevents most hangs, + * but this will bite us eventually... + */ + DRM_DEBUG("%s initialization failed " + "ctl %08x head %08x tail %08x start %08x. Ignoring, hope for the best!\n", + ring->name, + I915_READ_CTL(ring), + I915_READ_HEAD(ring), + I915_READ_TAIL(ring), + I915_READ_START(ring)); + } else { + DRM_ERROR("%s initialization failed " + "ctl %08x head %08x tail %08x start %08x\n", + ring->name, + I915_READ_CTL(ring), + I915_READ_HEAD(ring), + I915_READ_TAIL(ring), + I915_READ_START(ring)); + return -EIO; + } } if (!drm_core_check_feature(ring->dev, DRIVER_MODESET)) |