Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 6aa56062 authored by Chris Wilson's avatar Chris Wilson
Browse files

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: default avatarChris Wilson <chris@chris-wilson.co.uk>
parent f4e0b29b

drivers/gpu/drm/i915/intel_ringbuffer.c

+12 −1
Original line number Diff line number Diff line
@@ -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;