drm/i915/ringbuffer: Check that we setup the ringbuffer
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 8eaa60cc..e88214e 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -176,9 +176,10 @@
((ring->gem_object->size - PAGE_SIZE) & RING_NR_PAGES)
| RING_NO_REPORT | RING_VALID);
- head = I915_READ_HEAD(ring) & HEAD_ADDR;
/* If the head is still not zero, the ring is dead */
- if (head != 0) {
+ 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,