1/*
 2 * i915_sw_fence.h - library routines for N:M synchronisation points
 3 *
 4 * Copyright (C) 2016 Intel Corporation
 5 *
 6 * This file is released under the GPLv2.
 7 *
 8 */
 9
10#ifndef _I915_SW_FENCE_H_
11#define _I915_SW_FENCE_H_
12
13#include <linux/gfp.h>
14#include <linux/kref.h>
15#include <linux/notifier.h> /* for NOTIFY_DONE */
16#include <linux/wait.h>
17
18struct completion;
19struct dma_fence;
20struct dma_fence_ops;
21struct reservation_object;
22
23struct i915_sw_fence {
24	wait_queue_head_t wait;
25	unsigned long flags;
26	atomic_t pending;
27};
28
29#define I915_SW_FENCE_CHECKED_BIT	0 /* used internally for DAG checking */
30#define I915_SW_FENCE_PRIVATE_BIT	1 /* available for use by owner */
31#define I915_SW_FENCE_MASK		(~3)
32
33enum i915_sw_fence_notify {
34	FENCE_COMPLETE,
35	FENCE_FREE
36};
37
38typedef int (*i915_sw_fence_notify_t)(struct i915_sw_fence *,
39				      enum i915_sw_fence_notify state);
40#define __i915_sw_fence_call __aligned(4)
41
42void __i915_sw_fence_init(struct i915_sw_fence *fence,
43			  i915_sw_fence_notify_t fn,
44			  const char *name,
45			  struct lock_class_key *key);
46#ifdef CONFIG_LOCKDEP
47#define i915_sw_fence_init(fence, fn)				\
48do {								\
49	static struct lock_class_key __key;			\
50								\
51	__i915_sw_fence_init((fence), (fn), #fence, &__key);	\
52} while (0)
53#else
54#define i915_sw_fence_init(fence, fn)				\
55	__i915_sw_fence_init((fence), (fn), NULL, NULL)
56#endif
57
58#ifdef CONFIG_DRM_I915_SW_FENCE_DEBUG_OBJECTS
59void i915_sw_fence_fini(struct i915_sw_fence *fence);
60#else
61static inline void i915_sw_fence_fini(struct i915_sw_fence *fence) {}
62#endif
63
64void i915_sw_fence_commit(struct i915_sw_fence *fence);
65
66int i915_sw_fence_await_sw_fence(struct i915_sw_fence *fence,
67				 struct i915_sw_fence *after,
68				 wait_queue_entry_t *wq);
69int i915_sw_fence_await_sw_fence_gfp(struct i915_sw_fence *fence,
70				     struct i915_sw_fence *after,
71				     gfp_t gfp);
72int i915_sw_fence_await_dma_fence(struct i915_sw_fence *fence,
73				  struct dma_fence *dma,
74				  unsigned long timeout,
75				  gfp_t gfp);
76int i915_sw_fence_await_reservation(struct i915_sw_fence *fence,
77				    struct reservation_object *resv,
78				    const struct dma_fence_ops *exclude,
79				    bool write,
80				    unsigned long timeout,
81				    gfp_t gfp);
82
83static inline bool i915_sw_fence_signaled(const struct i915_sw_fence *fence)
84{
85	return atomic_read(&fence->pending) <= 0;
86}
87
88static inline bool i915_sw_fence_done(const struct i915_sw_fence *fence)
89{
90	return atomic_read(&fence->pending) < 0;
91}
92
93static inline void i915_sw_fence_wait(struct i915_sw_fence *fence)
94{
95	wait_event(fence->wait, i915_sw_fence_done(fence));
96}
97
98#endif /* _I915_SW_FENCE_H_ */