drivers/gpu/drm/i915/i915_sw_fence.h

   1 /*
   2  * SPDX-License-Identifier: MIT
   3  *
   4  * i915_sw_fence.h - library routines for N:M synchronisation points
   5  *
   6  * Copyright (C) 2016 Intel Corporation
   7  */
   8
   9 #ifndef _I915_SW_FENCE_H_
  10 #define _I915_SW_FENCE_H_
  11
  12 #include <linux/dma-fence.h>
  13 #include <linux/gfp.h>
  14 #include <linux/kref.h>
  15 #include <linux/notifier.h> /* for NOTIFY_DONE */
  16 #include <linux/wait.h>
  17
  18 struct completion;
  19 struct dma_resv;
  20
  21 struct i915_sw_fence {
  22         wait_queue_head_t wait;
  23         unsigned long flags;
  24         atomic_t pending;
  25         int error;
  26 };
  27
  28 #define I915_SW_FENCE_CHECKED_BIT       0 /* used internally for DAG checking */
  29 #define I915_SW_FENCE_PRIVATE_BIT       1 /* available for use by owner */
  30 #define I915_SW_FENCE_MASK              (~3)
  31
  32 enum i915_sw_fence_notify {
  33         FENCE_COMPLETE,
  34         FENCE_FREE
  35 };
  36
  37 typedef int (*i915_sw_fence_notify_t)(struct i915_sw_fence *,
  38                                       enum i915_sw_fence_notify state);
  39 #define __i915_sw_fence_call __aligned(4)
  40
  41 void __i915_sw_fence_init(struct i915_sw_fence *fence,
  42                           i915_sw_fence_notify_t fn,
  43                           const char *name,
  44                           struct lock_class_key *key);
  45 #ifdef CONFIG_LOCKDEP
  46 #define i915_sw_fence_init(fence, fn)                           \
  47 do {                                                            \
  48         static struct lock_class_key __key;                     \
  49                                                                 \
  50         __i915_sw_fence_init((fence), (fn), #fence, &__key);    \
  51 } while (0)
  52 #else
  53 #define i915_sw_fence_init(fence, fn)                           \
  54         __i915_sw_fence_init((fence), (fn), NULL, NULL)
  55 #endif
  56
  57 void i915_sw_fence_reinit(struct i915_sw_fence *fence);
  58
  59 #ifdef CONFIG_DRM_I915_SW_FENCE_DEBUG_OBJECTS
  60 void i915_sw_fence_fini(struct i915_sw_fence *fence);
  61 #else
  62 static inline void i915_sw_fence_fini(struct i915_sw_fence *fence) {}
  63 #endif
  64
  65 void i915_sw_fence_commit(struct i915_sw_fence *fence);
  66
  67 int i915_sw_fence_await_sw_fence(struct i915_sw_fence *fence,
  68                                  struct i915_sw_fence *after,
  69                                  wait_queue_entry_t *wq);
  70 int i915_sw_fence_await_sw_fence_gfp(struct i915_sw_fence *fence,
  71                                      struct i915_sw_fence *after,
  72                                      gfp_t gfp);
  73
  74 struct i915_sw_dma_fence_cb {
  75         struct dma_fence_cb base;
  76         struct i915_sw_fence *fence;
  77 };
  78
  79 int __i915_sw_fence_await_dma_fence(struct i915_sw_fence *fence,
  80                                     struct dma_fence *dma,
  81                                     struct i915_sw_dma_fence_cb *cb);
  82 int i915_sw_fence_await_dma_fence(struct i915_sw_fence *fence,
  83                                   struct dma_fence *dma,
  84                                   unsigned long timeout,
  85                                   gfp_t gfp);
  86
  87 int i915_sw_fence_await_reservation(struct i915_sw_fence *fence,
  88                                     struct dma_resv *resv,
  89                                     const struct dma_fence_ops *exclude,
  90                                     bool write,
  91                                     unsigned long timeout,
  92                                     gfp_t gfp);
  93
  94 bool i915_sw_fence_await(struct i915_sw_fence *fence);
  95 void i915_sw_fence_complete(struct i915_sw_fence *fence);
  96
  97 static inline bool i915_sw_fence_signaled(const struct i915_sw_fence *fence)
  98 {
  99         return atomic_read(&fence->pending) <= 0;
 100 }
 101
 102 static inline bool i915_sw_fence_done(const struct i915_sw_fence *fence)
 103 {
 104         return atomic_read(&fence->pending) < 0;
 105 }
 106
 107 static inline void i915_sw_fence_wait(struct i915_sw_fence *fence)
 108 {
 109         wait_event(fence->wait, i915_sw_fence_done(fence));
 110 }
 111
 112 static inline void
 113 i915_sw_fence_set_error_once(struct i915_sw_fence *fence, int error)
 114 {
 115         if (unlikely(error))
 116                 cmpxchg(&fence->error, 0, error);
 117 }
 118
 119 #endif /* _I915_SW_FENCE_H_ */