drm/radeon: Sync ME and PFP after CP semaphore waits v4

[deliverable/linux.git] / drivers / gpu / drm / radeon / cik.c

diff --git a/drivers/gpu/drm/radeon/cik.c b/drivers/gpu/drm/radeon/cik.c
index d61bc1841d5e5acecc739efabf2c195d73d26511..af2cbc647c738a966ba5065644f40d1de5d662ba 100644 (file)
--- a/drivers/gpu/drm/radeon/cik.c
+++ b/drivers/gpu/drm/radeon/cik.c
@@ -3920,6 +3920,17 @@ void cik_fence_compute_ring_emit(struct radeon_device *rdev,
        radeon_ring_write(ring, 0);
 }
 
+/**
+ * cik_semaphore_ring_emit - emit a semaphore on the CP ring
+ *
+ * @rdev: radeon_device pointer
+ * @ring: radeon ring buffer object
+ * @semaphore: radeon semaphore object
+ * @emit_wait: Is this a sempahore wait?
+ *
+ * Emits a semaphore signal/wait packet to the CP ring and prevents the PFP
+ * from running ahead of semaphore waits.
+ */
 bool cik_semaphore_ring_emit(struct radeon_device *rdev,
                             struct radeon_ring *ring,
                             struct radeon_semaphore *semaphore,
@@ -3932,6 +3943,12 @@ bool cik_semaphore_ring_emit(struct radeon_device *rdev,
        radeon_ring_write(ring, lower_32_bits(addr));
        radeon_ring_write(ring, (upper_32_bits(addr) & 0xffff) | sel);
 
+       if (emit_wait && ring->idx == RADEON_RING_TYPE_GFX_INDEX) {
+               /* Prevent the PFP from running ahead of the semaphore wait */
+               radeon_ring_write(ring, PACKET3(PACKET3_PFP_SYNC_ME, 0));
+               radeon_ring_write(ring, 0x0);
+       }
+
        return true;
 }