drm/nv84-nvc0: explicitly map semaphore buffer into channel vm

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nouveau_drv.h

@@ -240,6 +240,7 @@ struct nouveau_channel {
 		uint32_t sequence;
 		uint32_t sequence_ack;
 		atomic_t last_sequence_irq;
+		struct nouveau_vma vma;
 	} fence;
 
 	/* DMA push buffer */

drivers/gpu/drm/nouveau/nouveau_fence.c

@@ -336,6 +336,7 @@ semaphore_acquire(struct nouveau_channel *chan, struct nouveau_semaphore *sema)
 {
 	struct drm_nouveau_private *dev_priv = chan->dev->dev_private;
 	struct nouveau_fence *fence = NULL;
+	u64 offset = chan->fence.vma.offset + sema->mem->start;
 	int ret;
 
 	if (dev_priv->chipset < 0x84) {
@@ -345,13 +346,10 @@ semaphore_acquire(struct nouveau_channel *chan, struct nouveau_semaphore *sema)
 
 		BEGIN_RING(chan, NvSubSw, NV_SW_DMA_SEMAPHORE, 3);
 		OUT_RING  (chan, NvSema);
-		OUT_RING  (chan, sema->mem->start);
+		OUT_RING  (chan, offset);
 		OUT_RING  (chan, 1);
 	} else
 	if (dev_priv->chipset < 0xc0) {
-		struct nouveau_vma *vma = &dev_priv->fence.bo->vma;
-		u64 offset = vma->offset + sema->mem->start;
-
 		ret = RING_SPACE(chan, 7);
 		if (ret)
 			return ret;
@@ -364,9 +362,6 @@ semaphore_acquire(struct nouveau_channel *chan, struct nouveau_semaphore *sema)
 		OUT_RING  (chan, 1);
 		OUT_RING  (chan, 1); /* ACQUIRE_EQ */
 	} else {
-		struct nouveau_vma *vma = &dev_priv->fence.bo->vma;
-		u64 offset = vma->offset + sema->mem->start;
-
 		ret = RING_SPACE(chan, 5);
 		if (ret)
 			return ret;
@@ -394,6 +389,7 @@ semaphore_release(struct nouveau_channel *chan, struct nouveau_semaphore *sema)
 {
 	struct drm_nouveau_private *dev_priv = chan->dev->dev_private;
 	struct nouveau_fence *fence = NULL;
+	u64 offset = chan->fence.vma.offset + sema->mem->start;
 	int ret;
 
 	if (dev_priv->chipset < 0x84) {
@@ -403,14 +399,11 @@ semaphore_release(struct nouveau_channel *chan, struct nouveau_semaphore *sema)
 
 		BEGIN_RING(chan, NvSubSw, NV_SW_DMA_SEMAPHORE, 2);
 		OUT_RING  (chan, NvSema);
-		OUT_RING  (chan, sema->mem->start);
+		OUT_RING  (chan, offset);
 		BEGIN_RING(chan, NvSubSw, NV_SW_SEMAPHORE_RELEASE, 1);
 		OUT_RING  (chan, 1);
 	} else
 	if (dev_priv->chipset < 0xc0) {
-		struct nouveau_vma *vma = &dev_priv->fence.bo->vma;
-		u64 offset = vma->offset + sema->mem->start;
-
 		ret = RING_SPACE(chan, 7);
 		if (ret)
 			return ret;
@@ -423,9 +416,6 @@ semaphore_release(struct nouveau_channel *chan, struct nouveau_semaphore *sema)
 		OUT_RING  (chan, 1);
 		OUT_RING  (chan, 2); /* RELEASE */
 	} else {
-		struct nouveau_vma *vma = &dev_priv->fence.bo->vma;
-		u64 offset = vma->offset + sema->mem->start;
-
 		ret = RING_SPACE(chan, 5);
 		if (ret)
 			return ret;
@@ -540,6 +530,12 @@ nouveau_fence_channel_init(struct nouveau_channel *chan)
 		nouveau_gpuobj_ref(NULL, &obj);
 		if (ret)
 			return ret;
+	} else {
+		/* map fence bo into channel's vm */
+		ret = nouveau_bo_vma_add(dev_priv->fence.bo, chan->vm,
+					 &chan->fence.vma);
+		if (ret)
+			return ret;
 	}
 
 	INIT_LIST_HEAD(&chan->fence.pending);
@@ -551,10 +547,10 @@ nouveau_fence_channel_init(struct nouveau_channel *chan)
 void
 nouveau_fence_channel_fini(struct nouveau_channel *chan)
 {
+	struct drm_nouveau_private *dev_priv = chan->dev->dev_private;
 	struct nouveau_fence *tmp, *fence;
 
 	spin_lock(&chan->fence.lock);
-
 	list_for_each_entry_safe(fence, tmp, &chan->fence.pending, entry) {
 		fence->signalled = true;
 		list_del(&fence->entry);
@@ -564,8 +560,9 @@ nouveau_fence_channel_fini(struct nouveau_channel *chan)
 
 		kref_put(&fence->refcount, nouveau_fence_del);
 	}
-
 	spin_unlock(&chan->fence.lock);
+
+	nouveau_bo_vma_del(dev_priv->fence.bo, &chan->fence.vma);
 }
 
 int