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mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-25 13:43:55 +08:00

drm/i915/ringbuffer: Use the HEAD auto-reporting mechanism

My Sandybridge only reports 0 for the ring buffer registers, causing it
to hang as soon as we exhaust the available ring. As a workaround, take
advantage of our huge ring buffers and use the auto-reporting mechanism
to update the status page with the HEAD location every 64 KiB.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
This commit is contained in:
Chris Wilson 2010-10-29 21:44:37 +01:00
parent f4e0b29bf2
commit 6aa56062ea

View File

@ -174,7 +174,7 @@ static int init_ring_common(struct intel_ring_buffer *ring)
I915_WRITE_CTL(ring,
((ring->gem_object->size - PAGE_SIZE) & RING_NR_PAGES)
| RING_NO_REPORT | RING_VALID);
| RING_REPORT_64K | RING_VALID);
/* If the head is still not zero, the ring is dead */
if ((I915_READ_CTL(ring) & RING_VALID) == 0 ||
@ -691,6 +691,17 @@ int intel_wait_ring_buffer(struct intel_ring_buffer *ring, int n)
struct drm_device *dev = ring->dev;
drm_i915_private_t *dev_priv = dev->dev_private;
unsigned long end;
u32 head;
head = intel_read_status_page(ring, 4);
if (head) {
ring->head = head & HEAD_ADDR;
ring->space = ring->head - (ring->tail + 8);
if (ring->space < 0)
ring->space += ring->size;
if (ring->space >= n)
return 0;
}
trace_i915_ring_wait_begin (dev);
end = jiffies + 3 * HZ;