vmwgfx: Fix confusion caused by using "fence" in various places

This is needed before we introduce the fence objects.
Otherwise this will be even more confusing. The plan is to use the following:

seqno: A 32-bit sequence number that may be passed in the fifo.
marker: Objects, carrying a seqno, that track fifo submission time. They
are used for fifo lag based throttling.
fence objects: Kernel space objects, possibly accessible from user-space and
carrying a 32-bit seqno together with signaled status.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 171 insertions, 0 deletions

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_marker.c b/drivers/gpu/drm/vmwgfx/vmwgfx_marker.c
new file mode 100644
index 000000000000..8a8725c2716c
--- /dev/null
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_marker.c
@@ -0,0 +1,171 @@
+/**************************************************************************
+ *
+ * Copyright (C) 2010 VMware, Inc., Palo Alto, CA., USA
+ * 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, sub license, 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 NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDERS, AUTHORS 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 "vmwgfx_drv.h"
+
+struct vmw_marker {
+	struct list_head head;
+	uint32_t seqno;
+	struct timespec submitted;
+};
+
+void vmw_marker_queue_init(struct vmw_marker_queue *queue)
+{
+	INIT_LIST_HEAD(&queue->head);
+	queue->lag = ns_to_timespec(0);
+	getrawmonotonic(&queue->lag_time);
+	spin_lock_init(&queue->lock);
+}
+
+void vmw_marker_queue_takedown(struct vmw_marker_queue *queue)
+{
+	struct vmw_marker *marker, *next;
+
+	spin_lock(&queue->lock);
+	list_for_each_entry_safe(marker, next, &queue->head, head) {
+		kfree(marker);
+	}
+	spin_unlock(&queue->lock);
+}
+
+int vmw_marker_push(struct vmw_marker_queue *queue,
+		   uint32_t seqno)
+{
+	struct vmw_marker *marker = kmalloc(sizeof(*marker), GFP_KERNEL);
+
+	if (unlikely(!marker))
+		return -ENOMEM;
+
+	marker->seqno = seqno;
+	getrawmonotonic(&marker->submitted);
+	spin_lock(&queue->lock);
+	list_add_tail(&marker->head, &queue->head);
+	spin_unlock(&queue->lock);
+
+	return 0;
+}
+
+int vmw_marker_pull(struct vmw_marker_queue *queue,
+		   uint32_t signaled_seqno)
+{
+	struct vmw_marker *marker, *next;
+	struct timespec now;
+	bool updated = false;
+
+	spin_lock(&queue->lock);
+	getrawmonotonic(&now);
+
+	if (list_empty(&queue->head)) {
+		queue->lag = ns_to_timespec(0);
+		queue->lag_time = now;
+		updated = true;
+		goto out_unlock;
+	}
+
+	list_for_each_entry_safe(marker, next, &queue->head, head) {
+		if (signaled_seqno - marker->seqno > (1 << 30))
+			continue;
+
+		queue->lag = timespec_sub(now, marker->submitted);
+		queue->lag_time = now;
+		updated = true;
+		list_del(&marker->head);
+		kfree(marker);
+	}
+
+out_unlock:
+	spin_unlock(&queue->lock);
+
+	return (updated) ? 0 : -EBUSY;
+}
+
+static struct timespec vmw_timespec_add(struct timespec t1,
+					struct timespec t2)
+{
+	t1.tv_sec += t2.tv_sec;
+	t1.tv_nsec += t2.tv_nsec;
+	if (t1.tv_nsec >= 1000000000L) {
+		t1.tv_sec += 1;
+		t1.tv_nsec -= 1000000000L;
+	}
+
+	return t1;
+}
+
+static struct timespec vmw_fifo_lag(struct vmw_marker_queue *queue)
+{
+	struct timespec now;
+
+	spin_lock(&queue->lock);
+	getrawmonotonic(&now);
+	queue->lag = vmw_timespec_add(queue->lag,
+				      timespec_sub(now, queue->lag_time));
+	queue->lag_time = now;
+	spin_unlock(&queue->lock);
+	return queue->lag;
+}
+
+
+static bool vmw_lag_lt(struct vmw_marker_queue *queue,
+		       uint32_t us)
+{
+	struct timespec lag, cond;
+
+	cond = ns_to_timespec((s64) us * 1000);
+	lag = vmw_fifo_lag(queue);
+	return (timespec_compare(&lag, &cond) < 1);
+}
+
+int vmw_wait_lag(struct vmw_private *dev_priv,
+		 struct vmw_marker_queue *queue, uint32_t us)
+{
+	struct vmw_marker *marker;
+	uint32_t seqno;
+	int ret;
+
+	while (!vmw_lag_lt(queue, us)) {
+		spin_lock(&queue->lock);
+		if (list_empty(&queue->head))
+			seqno = atomic_read(&dev_priv->marker_seq);
+		else {
+			marker = list_first_entry(&queue->head,
+						 struct vmw_marker, head);
+			seqno = marker->seqno;
+		}
+		spin_unlock(&queue->lock);
+
+		ret = vmw_wait_seqno(dev_priv, false, seqno, true,
+					3*HZ);
+
+		if (unlikely(ret != 0))
+			return ret;
+
+		(void) vmw_marker_pull(queue, seqno);
+	}
+	return 0;
+}