1 files changed, 525 insertions, 0 deletions
diff --git a/drivers/gpu/drm/nouveau/nouveau_fence.c b/drivers/gpu/drm/nouveau/nouveau_fence.c
new file mode 100644
index 000000000..abcac7db4
--- /dev/null
+++ b/drivers/gpu/drm/nouveau/nouveau_fence.c
@@ -0,0 +1,525 @@
+/*
+ * Copyright (C) 2007 Ben Skeggs.
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial
+ * portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ */
+
+#include <linux/ktime.h>
+#include <linux/hrtimer.h>
+#include <linux/sched/signal.h>
+#include <trace/events/dma_fence.h>
+
+#include <nvif/cl826e.h>
+#include <nvif/notify.h>
+#include <nvif/event.h>
+
+#include "nouveau_drv.h"
+#include "nouveau_dma.h"
+#include "nouveau_fence.h"
+
+static const struct dma_fence_ops nouveau_fence_ops_uevent;
+static const struct dma_fence_ops nouveau_fence_ops_legacy;
+
+static inline struct nouveau_fence *
+from_fence(struct dma_fence *fence)
+{
+	return container_of(fence, struct nouveau_fence, base);
+}
+
+static inline struct nouveau_fence_chan *
+nouveau_fctx(struct nouveau_fence *fence)
+{
+	return container_of(fence->base.lock, struct nouveau_fence_chan, lock);
+}
+
+static int
+nouveau_fence_signal(struct nouveau_fence *fence)
+{
+	int drop = 0;
+
+	dma_fence_signal_locked(&fence->base);
+	list_del(&fence->head);
+	rcu_assign_pointer(fence->channel, NULL);
+
+	if (test_bit(DMA_FENCE_FLAG_USER_BITS, &fence->base.flags)) {
+		struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
+
+		if (!--fctx->notify_ref)
+			drop = 1;
+	}
+
+	dma_fence_put(&fence->base);
+	return drop;
+}
+
+static struct nouveau_fence *
+nouveau_local_fence(struct dma_fence *fence, struct nouveau_drm *drm)
+{
+	if (fence->ops != &nouveau_fence_ops_legacy &&
+	    fence->ops != &nouveau_fence_ops_uevent)
+		return NULL;
+
+	if (fence->context < drm->chan.context_base ||
+	    fence->context >= drm->chan.context_base + drm->chan.nr)
+		return NULL;
+
+	return from_fence(fence);
+}
+
+void
+nouveau_fence_context_kill(struct nouveau_fence_chan *fctx, int error)
+{
+	struct nouveau_fence *fence;
+
+	spin_lock_irq(&fctx->lock);
+	while (!list_empty(&fctx->pending)) {
+		fence = list_entry(fctx->pending.next, typeof(*fence), head);
+
+		if (error)
+			dma_fence_set_error(&fence->base, error);
+
+		if (nouveau_fence_signal(fence))
+			nvif_notify_put(&fctx->notify);
+	}
+	spin_unlock_irq(&fctx->lock);
+}
+
+void
+nouveau_fence_context_del(struct nouveau_fence_chan *fctx)
+{
+	nouveau_fence_context_kill(fctx, 0);
+	nvif_notify_dtor(&fctx->notify);
+	fctx->dead = 1;
+
+	/*
+	 * Ensure that all accesses to fence->channel complete before freeing
+	 * the channel.
+	 */
+	synchronize_rcu();
+}
+
+static void
+nouveau_fence_context_put(struct kref *fence_ref)
+{
+	kfree(container_of(fence_ref, struct nouveau_fence_chan, fence_ref));
+}
+
+void
+nouveau_fence_context_free(struct nouveau_fence_chan *fctx)
+{
+	kref_put(&fctx->fence_ref, nouveau_fence_context_put);
+}
+
+static int
+nouveau_fence_update(struct nouveau_channel *chan, struct nouveau_fence_chan *fctx)
+{
+	struct nouveau_fence *fence;
+	int drop = 0;
+	u32 seq = fctx->read(chan);
+
+	while (!list_empty(&fctx->pending)) {
+		fence = list_entry(fctx->pending.next, typeof(*fence), head);
+
+		if ((int)(seq - fence->base.seqno) < 0)
+			break;
+
+		drop |= nouveau_fence_signal(fence);
+	}
+
+	return drop;
+}
+
+static int
+nouveau_fence_wait_uevent_handler(struct nvif_notify *notify)
+{
+	struct nouveau_fence_chan *fctx =
+		container_of(notify, typeof(*fctx), notify);
+	unsigned long flags;
+	int ret = NVIF_NOTIFY_KEEP;
+
+	spin_lock_irqsave(&fctx->lock, flags);
+	if (!list_empty(&fctx->pending)) {
+		struct nouveau_fence *fence;
+		struct nouveau_channel *chan;
+
+		fence = list_entry(fctx->pending.next, typeof(*fence), head);
+		chan = rcu_dereference_protected(fence->channel, lockdep_is_held(&fctx->lock));
+		if (nouveau_fence_update(chan, fctx))
+			ret = NVIF_NOTIFY_DROP;
+	}
+	spin_unlock_irqrestore(&fctx->lock, flags);
+
+	return ret;
+}
+
+void
+nouveau_fence_context_new(struct nouveau_channel *chan, struct nouveau_fence_chan *fctx)
+{
+	struct nouveau_fence_priv *priv = (void*)chan->drm->fence;
+	struct nouveau_cli *cli = (void *)chan->user.client;
+	int ret;
+
+	INIT_LIST_HEAD(&fctx->flip);
+	INIT_LIST_HEAD(&fctx->pending);
+	spin_lock_init(&fctx->lock);
+	fctx->context = chan->drm->chan.context_base + chan->chid;
+
+	if (chan == chan->drm->cechan)
+		strcpy(fctx->name, "copy engine channel");
+	else if (chan == chan->drm->channel)
+		strcpy(fctx->name, "generic kernel channel");
+	else
+		strcpy(fctx->name, nvxx_client(&cli->base)->name);
+
+	kref_init(&fctx->fence_ref);
+	if (!priv->uevent)
+		return;
+
+	ret = nvif_notify_ctor(&chan->user, "fenceNonStallIntr",
+			       nouveau_fence_wait_uevent_handler,
+			       false, NV826E_V0_NTFY_NON_STALL_INTERRUPT,
+			       &(struct nvif_notify_uevent_req) { },
+			       sizeof(struct nvif_notify_uevent_req),
+			       sizeof(struct nvif_notify_uevent_rep),
+			       &fctx->notify);
+
+	WARN_ON(ret);
+}
+
+int
+nouveau_fence_emit(struct nouveau_fence *fence, struct nouveau_channel *chan)
+{
+	struct nouveau_fence_chan *fctx = chan->fence;
+	struct nouveau_fence_priv *priv = (void*)chan->drm->fence;
+	int ret;
+
+	fence->channel  = chan;
+	fence->timeout  = jiffies + (15 * HZ);
+
+	if (priv->uevent)
+		dma_fence_init(&fence->base, &nouveau_fence_ops_uevent,
+			       &fctx->lock, fctx->context, ++fctx->sequence);
+	else
+		dma_fence_init(&fence->base, &nouveau_fence_ops_legacy,
+			       &fctx->lock, fctx->context, ++fctx->sequence);
+	kref_get(&fctx->fence_ref);
+
+	ret = fctx->emit(fence);
+	if (!ret) {
+		dma_fence_get(&fence->base);
+		spin_lock_irq(&fctx->lock);
+
+		if (nouveau_fence_update(chan, fctx))
+			nvif_notify_put(&fctx->notify);
+
+		list_add_tail(&fence->head, &fctx->pending);
+		spin_unlock_irq(&fctx->lock);
+	}
+
+	return ret;
+}
+
+bool
+nouveau_fence_done(struct nouveau_fence *fence)
+{
+	if (fence->base.ops == &nouveau_fence_ops_legacy ||
+	    fence->base.ops == &nouveau_fence_ops_uevent) {
+		struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
+		struct nouveau_channel *chan;
+		unsigned long flags;
+
+		if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->base.flags))
+			return true;
+
+		spin_lock_irqsave(&fctx->lock, flags);
+		chan = rcu_dereference_protected(fence->channel, lockdep_is_held(&fctx->lock));
+		if (chan && nouveau_fence_update(chan, fctx))
+			nvif_notify_put(&fctx->notify);
+		spin_unlock_irqrestore(&fctx->lock, flags);
+	}
+	return dma_fence_is_signaled(&fence->base);
+}
+
+static long
+nouveau_fence_wait_legacy(struct dma_fence *f, bool intr, long wait)
+{
+	struct nouveau_fence *fence = from_fence(f);
+	unsigned long sleep_time = NSEC_PER_MSEC / 1000;
+	unsigned long t = jiffies, timeout = t + wait;
+
+	while (!nouveau_fence_done(fence)) {
+		ktime_t kt;
+
+		t = jiffies;
+
+		if (wait != MAX_SCHEDULE_TIMEOUT && time_after_eq(t, timeout)) {
+			__set_current_state(TASK_RUNNING);
+			return 0;
+		}
+
+		__set_current_state(intr ? TASK_INTERRUPTIBLE :
+					   TASK_UNINTERRUPTIBLE);
+
+		kt = sleep_time;
+		schedule_hrtimeout(&kt, HRTIMER_MODE_REL);
+		sleep_time *= 2;
+		if (sleep_time > NSEC_PER_MSEC)
+			sleep_time = NSEC_PER_MSEC;
+
+		if (intr && signal_pending(current))
+			return -ERESTARTSYS;
+	}
+
+	__set_current_state(TASK_RUNNING);
+
+	return timeout - t;
+}
+
+static int
+nouveau_fence_wait_busy(struct nouveau_fence *fence, bool intr)
+{
+	int ret = 0;
+
+	while (!nouveau_fence_done(fence)) {
+		if (time_after_eq(jiffies, fence->timeout)) {
+			ret = -EBUSY;
+			break;
+		}
+
+		__set_current_state(intr ?
+				    TASK_INTERRUPTIBLE :
+				    TASK_UNINTERRUPTIBLE);
+
+		if (intr && signal_pending(current)) {
+			ret = -ERESTARTSYS;
+			break;
+		}
+	}
+
+	__set_current_state(TASK_RUNNING);
+	return ret;
+}
+
+int
+nouveau_fence_wait(struct nouveau_fence *fence, bool lazy, bool intr)
+{
+	long ret;
+
+	if (!lazy)
+		return nouveau_fence_wait_busy(fence, intr);
+
+	ret = dma_fence_wait_timeout(&fence->base, intr, 15 * HZ);
+	if (ret < 0)
+		return ret;
+	else if (!ret)
+		return -EBUSY;
+	else
+		return 0;
+}
+
+int
+nouveau_fence_sync(struct nouveau_bo *nvbo, struct nouveau_channel *chan,
+		   bool exclusive, bool intr)
+{
+	struct nouveau_fence_chan *fctx = chan->fence;
+	struct dma_resv *resv = nvbo->bo.base.resv;
+	int i, ret;
+
+	ret = dma_resv_reserve_fences(resv, 1);
+	if (ret)
+		return ret;
+
+	/* Waiting for the writes first causes performance regressions
+	 * under some circumstances. So manually wait for the reads first.
+	 */
+	for (i = 0; i < 2; ++i) {
+		struct dma_resv_iter cursor;
+		struct dma_fence *fence;
+
+		dma_resv_for_each_fence(&cursor, resv,
+					dma_resv_usage_rw(exclusive),
+					fence) {
+			enum dma_resv_usage usage;
+			struct nouveau_fence *f;
+
+			usage = dma_resv_iter_usage(&cursor);
+			if (i == 0 && usage == DMA_RESV_USAGE_WRITE)
+				continue;
+
+			f = nouveau_local_fence(fence, chan->drm);
+			if (f) {
+				struct nouveau_channel *prev;
+				bool must_wait = true;
+
+				rcu_read_lock();
+				prev = rcu_dereference(f->channel);
+				if (prev && (prev == chan ||
+					     fctx->sync(f, prev, chan) == 0))
+					must_wait = false;
+				rcu_read_unlock();
+				if (!must_wait)
+					continue;
+			}
+
+			ret = dma_fence_wait(fence, intr);
+			if (ret)
+				return ret;
+		}
+	}
+
+	return 0;
+}
+
+void
+nouveau_fence_unref(struct nouveau_fence **pfence)
+{
+	if (*pfence)
+		dma_fence_put(&(*pfence)->base);
+	*pfence = NULL;
+}
+
+int
+nouveau_fence_new(struct nouveau_channel *chan, bool sysmem,
+		  struct nouveau_fence **pfence)
+{
+	struct nouveau_fence *fence;
+	int ret = 0;
+
+	if (unlikely(!chan->fence))
+		return -ENODEV;
+
+	fence = kzalloc(sizeof(*fence), GFP_KERNEL);
+	if (!fence)
+		return -ENOMEM;
+
+	ret = nouveau_fence_emit(fence, chan);
+	if (ret)
+		nouveau_fence_unref(&fence);
+
+	*pfence = fence;
+	return ret;
+}
+
+static const char *nouveau_fence_get_get_driver_name(struct dma_fence *fence)
+{
+	return "nouveau";
+}
+
+static const char *nouveau_fence_get_timeline_name(struct dma_fence *f)
+{
+	struct nouveau_fence *fence = from_fence(f);
+	struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
+
+	return !fctx->dead ? fctx->name : "dead channel";
+}
+
+/*
+ * In an ideal world, read would not assume the channel context is still alive.
+ * This function may be called from another device, running into free memory as a
+ * result. The drm node should still be there, so we can derive the index from
+ * the fence context.
+ */
+static bool nouveau_fence_is_signaled(struct dma_fence *f)
+{
+	struct nouveau_fence *fence = from_fence(f);
+	struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
+	struct nouveau_channel *chan;
+	bool ret = false;
+
+	rcu_read_lock();
+	chan = rcu_dereference(fence->channel);
+	if (chan)
+		ret = (int)(fctx->read(chan) - fence->base.seqno) >= 0;
+	rcu_read_unlock();
+
+	return ret;
+}
+
+static bool nouveau_fence_no_signaling(struct dma_fence *f)
+{
+	struct nouveau_fence *fence = from_fence(f);
+
+	/*
+	 * caller should have a reference on the fence,
+	 * else fence could get freed here
+	 */
+	WARN_ON(kref_read(&fence->base.refcount) <= 1);
+
+	/*
+	 * This needs uevents to work correctly, but dma_fence_add_callback relies on
+	 * being able to enable signaling. It will still get signaled eventually,
+	 * just not right away.
+	 */
+	if (nouveau_fence_is_signaled(f)) {
+		list_del(&fence->head);
+
+		dma_fence_put(&fence->base);
+		return false;
+	}
+
+	return true;
+}
+
+static void nouveau_fence_release(struct dma_fence *f)
+{
+	struct nouveau_fence *fence = from_fence(f);
+	struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
+
+	kref_put(&fctx->fence_ref, nouveau_fence_context_put);
+	dma_fence_free(&fence->base);
+}
+
+static const struct dma_fence_ops nouveau_fence_ops_legacy = {
+	.get_driver_name = nouveau_fence_get_get_driver_name,
+	.get_timeline_name = nouveau_fence_get_timeline_name,
+	.enable_signaling = nouveau_fence_no_signaling,
+	.signaled = nouveau_fence_is_signaled,
+	.wait = nouveau_fence_wait_legacy,
+	.release = nouveau_fence_release
+};
+
+static bool nouveau_fence_enable_signaling(struct dma_fence *f)
+{
+	struct nouveau_fence *fence = from_fence(f);
+	struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
+	bool ret;
+
+	if (!fctx->notify_ref++)
+		nvif_notify_get(&fctx->notify);
+
+	ret = nouveau_fence_no_signaling(f);
+	if (ret)
+		set_bit(DMA_FENCE_FLAG_USER_BITS, &fence->base.flags);
+	else if (!--fctx->notify_ref)
+		nvif_notify_put(&fctx->notify);
+
+	return ret;
+}
+
+static const struct dma_fence_ops nouveau_fence_ops_uevent = {
+	.get_driver_name = nouveau_fence_get_get_driver_name,
+	.get_timeline_name = nouveau_fence_get_timeline_name,
+	.enable_signaling = nouveau_fence_enable_signaling,
+	.signaled = nouveau_fence_is_signaled,
+	.release = nouveau_fence_release
+};