From: Chris Wilson Date: Wed, 14 Nov 2012 09:15:14 +0000 (+0000) Subject: drm/i915: Use LRI to update the semaphore registers X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=1c8b46fc8c865189f562c9ab163d63863759712f;p=linux-beck.git drm/i915: Use LRI to update the semaphore registers The bspec was recently updated to remove the ability to update the semaphore using the MI_SEMAPHORE_BOX command, the ability to wait upon the semaphore value remained. Instead the advice is to update the register using the MI_LOAD_REGISTER_IMM command. In cursory testing, semaphores continue to function - the question is whether this fixes some of the deadlocks where the semaphore registers contained stale values? Signed-off-by: Chris Wilson Cc: Daniel J Blueman Reviewed-by: Ben Widawsky Signed-off-by: Daniel Vetter --- diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 1aa76892a830..987eb5fdaf39 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -558,12 +558,9 @@ update_mboxes(struct intel_ring_buffer *ring, u32 seqno, u32 mmio_offset) { - intel_ring_emit(ring, MI_SEMAPHORE_MBOX | - MI_SEMAPHORE_GLOBAL_GTT | - MI_SEMAPHORE_REGISTER | - MI_SEMAPHORE_UPDATE); - intel_ring_emit(ring, seqno); + intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1)); intel_ring_emit(ring, mmio_offset); + intel_ring_emit(ring, seqno); } /**