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diff --git a/src/gallium/drivers/crocus/crocus_fine_fence.h b/src/gallium/drivers/crocus/crocus_fine_fence.h
new file mode 100644
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+++ b/src/gallium/drivers/crocus/crocus_fine_fence.h
@@ -0,0 +1,109 @@
+/*
+ * Copyright © 2020 Intel Corporation
+ *
+ * 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 AUTHORS OR COPYRIGHT HOLDERS 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.
+ */
+
+#ifndef CROCUS_FINE_FENCE_DOT_H
+#define CROCUS_FINE_FENCE_DOT_H
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "crocus_screen.h"
+#include "crocus_resource.h"
+
+/**
+ * A lightweight sequence number fence.
+ *
+ * We emit PIPE_CONTROLs inside a batch (possibly in the middle)
+ * which update a monotonically increasing, 32-bit counter.  We
+ * can then check if that moment has passed by either:
+ *
+ * 1. Checking on the CPU by snooping on the DWord via a coherent map
+ *
+ * 2. Blocking on the GPU with MI_SEMAPHORE_WAIT from a second batch
+ *    (relying on mid-batch preemption to switch GPU execution to the
+ *    batch that writes it).
+ */
+struct crocus_fine_fence {
+   struct pipe_reference reference;
+
+   /** Buffer where the seqno lives */
+   struct crocus_state_ref ref;
+
+   /** Coherent CPU map of the buffer containing the seqno DWord. */
+   const uint32_t *map;
+
+   /**
+    * A drm_syncobj pointing which will be signaled at the end of the
+    * batch which writes this seqno.  This can be used to block until
+    * the seqno has definitely passed (but may wait longer than necessary).
+    */
+   struct crocus_syncobj *syncobj;
+
+#define CROCUS_FENCE_BOTTOM_OF_PIPE 0x0 /**< Written by bottom-of-pipe flush */
+#define CROCUS_FENCE_TOP_OF_PIPE    0x1 /**< Written by top-of-pipe flush */
+#define CROCUS_FENCE_END            0x2 /**< Written at the end of a batch */
+
+   /** Information about the type of flush involved (see CROCUS_FENCE_*) */
+   uint32_t flags;
+
+   /**
+    * Sequence number expected to be written by the flush we inserted
+    * when creating this fence.  The crocus_fine_fence is 'signaled' when *@map
+    * (written by the flush on the GPU) is greater-than-or-equal to @seqno.
+    */
+   uint32_t seqno;
+};
+
+void crocus_fine_fence_init(struct crocus_batch *batch);
+
+struct crocus_fine_fence *crocus_fine_fence_new(struct crocus_batch *batch,
+                                                unsigned flags);
+
+void crocus_fine_fence_destroy(struct crocus_screen *screen,
+                               struct crocus_fine_fence *sq);
+
+static inline void
+crocus_fine_fence_reference(struct crocus_screen *screen,
+                            struct crocus_fine_fence **dst,
+                            struct crocus_fine_fence *src)
+{
+   if (pipe_reference(&(*dst)->reference, &src->reference))
+      crocus_fine_fence_destroy(screen, *dst);
+
+   *dst = src;
+}
+
+/**
+ * Return true if this seqno has passed.
+ *
+ * NULL is considered signaled.
+ */
+static inline bool
+crocus_fine_fence_signaled(const struct crocus_fine_fence *sq)
+{
+   if (sq && !sq->map)
+      return false;
+   return !sq || (READ_ONCE(*sq->map) >= sq->seqno);
+}
+
+#endif