From 498d2ac15ce0fc08edb005a7faf9ed6b5aa028d8 Mon Sep 17 00:00:00 2001 From: Mika Kuoppala Date: Tue, 4 Dec 2012 15:12:04 +0200 Subject: drm/i915: Add intel_ring_handle_seqno wrap If there are pre-wrap values in semaphore-mbox registers after wrap, syncing against some after-wrap request will complete immediately. Fix this by emitting ring commands to set mbox registers to zero when the wrap happens. v2: Use __intel_ring_begin to emit ring commands, from Chris Wilson. Signed-off-by: Mika Kuoppala Reviewed-by: Chris Wilson [danvet: Add a small comment to handle_seqno_wrap.] Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_ringbuffer.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'drivers/gpu/drm/i915/intel_ringbuffer.c') diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 01a660a7c167..0d03dc649c5e 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -1402,6 +1402,28 @@ int intel_ring_begin(struct intel_ring_buffer *ring, return __intel_ring_begin(ring, num_dwords * sizeof(uint32_t)); } +int intel_ring_handle_seqno_wrap(struct intel_ring_buffer *ring) +{ + int ret; + + BUG_ON(ring->outstanding_lazy_request); + + if (INTEL_INFO(ring->dev)->gen < 6) + return 0; + + ret = __intel_ring_begin(ring, 6 * sizeof(uint32_t)); + if (ret) + return ret; + + /* Leaving a stale, pre-wrap seqno behind in the mboxes will result in + * post-wrap semaphore waits completing immediately. Clear them. */ + update_mboxes(ring, ring->signal_mbox[0]); + update_mboxes(ring, ring->signal_mbox[1]); + intel_ring_advance(ring); + + return 0; +} + void intel_ring_advance(struct intel_ring_buffer *ring) { struct drm_i915_private *dev_priv = ring->dev->dev_private; -- cgit v1.2.3