[PATCH 3/3] drm/radeon/kms: sync across multiple rings when doing bo moves v3

[alexdeucher at gmail.com]

From: Alex Deucher <alexander.deucher at amd.com>

We need to synchronize across rings when doing a bo move to make
sure we the buffer is idle if it's in use by a different ring than
the ring doing the move.

v2: fix fence setup for bo moves

v3: add missing ring lock/unlock

Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
---
 drivers/gpu/drm/radeon/radeon.h      |    2 +
 drivers/gpu/drm/radeon/radeon_asic.c |    3 ++
 drivers/gpu/drm/radeon/radeon_ttm.c  |   38 ++++++++++++++++++++++++++++++---
 3 files changed, 39 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index 3483ed9..7cb63cd 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -1489,6 +1489,8 @@ struct radeon_device {
 	unsigned 		debugfs_count;
 	/* virtual memory */
 	struct radeon_vm_manager	vm_manager;
+	/* ring used for bo copies */
+	u32				copy_ring;
 };
 
 int radeon_device_init(struct radeon_device *rdev,
diff --git a/drivers/gpu/drm/radeon/radeon_asic.c b/drivers/gpu/drm/radeon/radeon_asic.c
index 123a196..36a6192 100644
--- a/drivers/gpu/drm/radeon/radeon_asic.c
+++ b/drivers/gpu/drm/radeon/radeon_asic.c
@@ -1036,6 +1036,9 @@ int radeon_asic_init(struct radeon_device *rdev)
 	else
 		rdev->num_crtc = 2;
 
+	/* set the ring used for bo copies */
+	rdev->copy_ring = RADEON_RING_TYPE_GFX_INDEX;
+
 	switch (rdev->family) {
 	case CHIP_R100:
 	case CHIP_RV100:
diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c
index b0ebaf8..1882025 100644
--- a/drivers/gpu/drm/radeon/radeon_ttm.c
+++ b/drivers/gpu/drm/radeon/radeon_ttm.c
@@ -223,10 +223,10 @@ static int radeon_move_blit(struct ttm_buffer_object *bo,
 	struct radeon_device *rdev;
 	uint64_t old_start, new_start;
 	struct radeon_fence *fence;
-	int r;
+	int r, i;
 
 	rdev = radeon_get_rdev(bo->bdev);
-	r = radeon_fence_create(rdev, &fence, RADEON_RING_TYPE_GFX_INDEX);
+	r = radeon_fence_create(rdev, &fence, rdev->copy_ring);
 	if (unlikely(r)) {
 		return r;
 	}
@@ -255,13 +255,43 @@ static int radeon_move_blit(struct ttm_buffer_object *bo,
 		DRM_ERROR("Unknown placement %d\n", old_mem->mem_type);
 		return -EINVAL;
 	}
-	if (!rdev->ring[RADEON_RING_TYPE_GFX_INDEX].ready) {
-		DRM_ERROR("Trying to move memory with CP turned off.\n");
+	if (!rdev->ring[rdev->copy_ring].ready) {
+		DRM_ERROR("Trying to move memory with ring turned off.\n");
 		return -EINVAL;
 	}
 
 	BUILD_BUG_ON((PAGE_SIZE % RADEON_GPU_PAGE_SIZE) != 0);
 
+	/* sync other rings */
+	if (rdev->family >= CHIP_R600) {
+		for (i = 0; i < RADEON_NUM_RINGS; ++i) {
+			/* no need to sync to our own or unused rings */
+			if (i == rdev->copy_ring || !rdev->ring[i].ready)
+				continue;
+
+			if (!fence->semaphore) {
+				r = radeon_semaphore_create(rdev, &fence->semaphore);
+				/* FIXME: handle semaphore error */
+				if (r)
+					continue;
+			}
+
+			r = radeon_ring_lock(rdev, &rdev->ring[i], 3);
+			/* FIXME: handle ring lock error */
+			if (r)
+				continue;
+			radeon_semaphore_emit_signal(rdev, i, fence->semaphore);
+			radeon_ring_unlock_commit(rdev, &rdev->ring[i]);
+
+			r = radeon_ring_lock(rdev, &rdev->ring[rdev->copy_ring], 3);
+			/* FIXME: handle ring lock error */
+			if (r)
+				continue;
+			radeon_semaphore_emit_wait(rdev, rdev->copy_ring, fence->semaphore);
+			radeon_ring_unlock_commit(rdev, &rdev->ring[rdev->copy_ring]);
+		}
+	}
+
 	r = radeon_copy(rdev, old_start, new_start,
 			new_mem->num_pages * (PAGE_SIZE / RADEON_GPU_PAGE_SIZE), /* GPU pages */
 			fence);
-- 
1.7.3.4