drm/nv84: switch to new-style semaphores
These are the same semaphores nvc0 will use, and they potentially allow
us to do much cooler things than our current inter-channel sync impl.
Lets switch to them where possible now for some testing.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
diff --git a/drivers/gpu/drm/nouveau/nouveau_fence.c b/drivers/gpu/drm/nouveau/nouveau_fence.c
index 221b846..37bccd5 100644
--- a/drivers/gpu/drm/nouveau/nouveau_fence.c
+++ b/drivers/gpu/drm/nouveau/nouveau_fence.c
@@ -259,11 +259,12 @@
}
static struct nouveau_semaphore *
-alloc_semaphore(struct drm_device *dev)
+semaphore_alloc(struct drm_device *dev)
{
struct drm_nouveau_private *dev_priv = dev->dev_private;
struct nouveau_semaphore *sema;
- int ret;
+ int size = (dev_priv->chipset < 0x84) ? 4 : 16;
+ int ret, i;
if (!USE_SEMA(dev))
return NULL;
@@ -277,9 +278,9 @@
goto fail;
spin_lock(&dev_priv->fence.lock);
- sema->mem = drm_mm_search_free(&dev_priv->fence.heap, 4, 0, 0);
+ sema->mem = drm_mm_search_free(&dev_priv->fence.heap, size, 0, 0);
if (sema->mem)
- sema->mem = drm_mm_get_block_atomic(sema->mem, 4, 0);
+ sema->mem = drm_mm_get_block_atomic(sema->mem, size, 0);
spin_unlock(&dev_priv->fence.lock);
if (!sema->mem)
@@ -287,7 +288,8 @@
kref_init(&sema->ref);
sema->dev = dev;
- nouveau_bo_wr32(dev_priv->fence.bo, sema->mem->start / 4, 0);
+ for (i = sema->mem->start; i < sema->mem->start + size; i += 4)
+ nouveau_bo_wr32(dev_priv->fence.bo, i / 4, 0);
return sema;
fail:
@@ -296,7 +298,7 @@
}
static void
-free_semaphore(struct kref *ref)
+semaphore_free(struct kref *ref)
{
struct nouveau_semaphore *sema =
container_of(ref, struct nouveau_semaphore, ref);
@@ -318,30 +320,25 @@
if (unlikely(!signalled))
nouveau_bo_wr32(dev_priv->fence.bo, sema->mem->start / 4, 1);
- kref_put(&sema->ref, free_semaphore);
+ kref_put(&sema->ref, semaphore_free);
}
static int
-emit_semaphore(struct nouveau_channel *chan, int method,
- struct nouveau_semaphore *sema)
+semaphore_acquire(struct nouveau_channel *chan, struct nouveau_semaphore *sema)
{
- struct drm_nouveau_private *dev_priv = sema->dev->dev_private;
- struct nouveau_fence *fence;
- bool smart = (dev_priv->card_type >= NV_50);
+ struct drm_nouveau_private *dev_priv = chan->dev->dev_private;
+ struct nouveau_fence *fence = NULL;
int ret;
- ret = RING_SPACE(chan, smart ? 8 : 4);
- if (ret)
- return ret;
+ if (dev_priv->chipset < 0x84) {
+ ret = RING_SPACE(chan, 3);
+ if (ret)
+ return ret;
- if (smart) {
- BEGIN_RING(chan, NvSubSw, NV_SW_DMA_SEMAPHORE, 1);
- OUT_RING(chan, NvSema);
- }
- BEGIN_RING(chan, NvSubSw, NV_SW_SEMAPHORE_OFFSET, 1);
- OUT_RING(chan, sema->mem->start);
-
- if (smart && method == NV_SW_SEMAPHORE_ACQUIRE) {
+ BEGIN_RING(chan, NvSubSw, NV_SW_SEMAPHORE_OFFSET, 2);
+ OUT_RING (chan, sema->mem->start);
+ OUT_RING (chan, 1);
+ } else {
/*
* NV50 tries to be too smart and context-switch
* between semaphores instead of doing a "first come,
@@ -358,21 +355,18 @@
* RELEASE is already scheduled to be executed in
* another channel.
*/
- BEGIN_RING(chan, NvSubSw, NV_SW_YIELD, 1);
- OUT_RING(chan, 0);
- }
- BEGIN_RING(chan, NvSubSw, method, 1);
- OUT_RING(chan, 1);
+ ret = RING_SPACE(chan, 7);
+ if (ret)
+ return ret;
- if (smart && method == NV_SW_SEMAPHORE_RELEASE) {
- /*
- * Force the card to context switch, there may be
- * another channel waiting for the semaphore we just
- * released.
- */
- BEGIN_RING(chan, NvSubSw, NV_SW_YIELD, 1);
- OUT_RING(chan, 0);
+ BEGIN_RING(chan, NvSubSw, 0x0080, 1);
+ OUT_RING (chan, 0);
+ BEGIN_RING(chan, NvSubSw, 0x0010, 4);
+ OUT_RING (chan, upper_32_bits(sema->mem->start));
+ OUT_RING (chan, lower_32_bits(sema->mem->start));
+ OUT_RING (chan, 1);
+ OUT_RING (chan, 1); /* ACQUIRE_EQ */
}
/* Delay semaphore destruction until its work is done */
@@ -383,7 +377,53 @@
kref_get(&sema->ref);
nouveau_fence_work(fence, semaphore_work, sema);
nouveau_fence_unref(&fence);
+ return 0;
+}
+static int
+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;
+ int ret;
+
+ if (dev_priv->chipset < 0x84) {
+ ret = RING_SPACE(chan, 4);
+ if (ret)
+ return ret;
+
+ BEGIN_RING(chan, NvSubSw, NV_SW_SEMAPHORE_OFFSET, 1);
+ OUT_RING (chan, sema->mem->start);
+ BEGIN_RING(chan, NvSubSw, NV_SW_SEMAPHORE_RELEASE, 1);
+ OUT_RING (chan, 1);
+ } else {
+ /*
+ * Emits release and forces the card to context switch right
+ * afterwards, there may be another channel waiting for the
+ * semaphore
+ */
+
+ ret = RING_SPACE(chan, 7);
+ if (ret)
+ return ret;
+
+ BEGIN_RING(chan, NvSubSw, 0x0010, 4);
+ OUT_RING (chan, upper_32_bits(sema->mem->start));
+ OUT_RING (chan, lower_32_bits(sema->mem->start));
+ OUT_RING (chan, 1);
+ OUT_RING (chan, 2); /* RELEASE */
+ BEGIN_RING(chan, NvSubSw, 0x0080, 1);
+ OUT_RING (chan, 0);
+ }
+
+ /* Delay semaphore destruction until its work is done */
+ ret = nouveau_fence_new(chan, &fence, true);
+ if (ret)
+ return ret;
+
+ kref_get(&sema->ref);
+ nouveau_fence_work(fence, semaphore_work, sema);
+ nouveau_fence_unref(&fence);
return 0;
}
@@ -400,7 +440,7 @@
nouveau_fence_signalled(fence)))
goto out;
- sema = alloc_semaphore(dev);
+ sema = semaphore_alloc(dev);
if (!sema) {
/* Early card or broken userspace, fall back to
* software sync. */
@@ -418,17 +458,17 @@
}
/* Make wchan wait until it gets signalled */
- ret = emit_semaphore(wchan, NV_SW_SEMAPHORE_ACQUIRE, sema);
+ ret = semaphore_acquire(wchan, sema);
if (ret)
goto out_unlock;
/* Signal the semaphore from chan */
- ret = emit_semaphore(chan, NV_SW_SEMAPHORE_RELEASE, sema);
+ ret = semaphore_release(chan, sema);
out_unlock:
mutex_unlock(&chan->mutex);
out_unref:
- kref_put(&sema->ref, free_semaphore);
+ kref_put(&sema->ref, semaphore_free);
out:
if (chan)
nouveau_channel_put_unlocked(&chan);
@@ -519,11 +559,12 @@
nouveau_fence_init(struct drm_device *dev)
{
struct drm_nouveau_private *dev_priv = dev->dev_private;
+ int size = (dev_priv->chipset < 0x84) ? 4096 : 16384;
int ret;
/* Create a shared VRAM heap for cross-channel sync. */
if (USE_SEMA(dev)) {
- ret = nouveau_bo_new(dev, NULL, 4096, 0, TTM_PL_FLAG_VRAM,
+ ret = nouveau_bo_new(dev, NULL, size, 0, TTM_PL_FLAG_VRAM,
0, 0, false, true, &dev_priv->fence.bo);
if (ret)
return ret;