1 /*
2 * Copyright (c) 2014-2016 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 */
23
24 #ifndef __INTEL_FRONTBUFFER_H__
25 #define __INTEL_FRONTBUFFER_H__
26
27 #include <linux/atomic.h>
28 #include <linux/kref.h>
29
30 #include "gem/i915_gem_object_types.h"
31 #include "i915_active.h"
32
33 struct drm_i915_private;
34
35 enum fb_op_origin {
36 ORIGIN_CPU = 0,
37 ORIGIN_CS,
38 ORIGIN_FLIP,
39 ORIGIN_DIRTYFB,
40 ORIGIN_CURSOR_UPDATE,
41 };
42
43 struct intel_frontbuffer {
44 struct kref ref;
45 atomic_t bits;
46 struct i915_active write;
47 struct drm_i915_gem_object *obj;
48 struct rcu_head rcu;
49 };
50
51 void intel_frontbuffer_flip_prepare(struct drm_i915_private *i915,
52 unsigned frontbuffer_bits);
53 void intel_frontbuffer_flip_complete(struct drm_i915_private *i915,
54 unsigned frontbuffer_bits);
55 void intel_frontbuffer_flip(struct drm_i915_private *i915,
56 unsigned frontbuffer_bits);
57
58 void intel_frontbuffer_put(struct intel_frontbuffer *front);
59
60 static inline struct intel_frontbuffer *
__intel_frontbuffer_get(const struct drm_i915_gem_object * obj)61 __intel_frontbuffer_get(const struct drm_i915_gem_object *obj)
62 {
63 struct intel_frontbuffer *front;
64
65 if (likely(!rcu_access_pointer(obj->frontbuffer)))
66 return NULL;
67
68 rcu_read_lock();
69 do {
70 front = rcu_dereference(obj->frontbuffer);
71 if (!front)
72 break;
73
74 if (unlikely(!kref_get_unless_zero(&front->ref)))
75 continue;
76
77 if (likely(front == rcu_access_pointer(obj->frontbuffer)))
78 break;
79
80 intel_frontbuffer_put(front);
81 } while (1);
82 rcu_read_unlock();
83
84 return front;
85 }
86
87 struct intel_frontbuffer *
88 intel_frontbuffer_get(struct drm_i915_gem_object *obj);
89
90 void __intel_fb_invalidate(struct intel_frontbuffer *front,
91 enum fb_op_origin origin,
92 unsigned int frontbuffer_bits);
93
94 /**
95 * intel_frontbuffer_invalidate - invalidate frontbuffer object
96 * @front: GEM object to invalidate
97 * @origin: which operation caused the invalidation
98 *
99 * This function gets called every time rendering on the given object starts and
100 * frontbuffer caching (fbc, low refresh rate for DRRS, panel self refresh) must
101 * be invalidated. For ORIGIN_CS any subsequent invalidation will be delayed
102 * until the rendering completes or a flip on this frontbuffer plane is
103 * scheduled.
104 */
intel_frontbuffer_invalidate(struct intel_frontbuffer * front,enum fb_op_origin origin)105 static inline bool intel_frontbuffer_invalidate(struct intel_frontbuffer *front,
106 enum fb_op_origin origin)
107 {
108 unsigned int frontbuffer_bits;
109
110 if (!front)
111 return false;
112
113 frontbuffer_bits = atomic_read(&front->bits);
114 if (!frontbuffer_bits)
115 return false;
116
117 __intel_fb_invalidate(front, origin, frontbuffer_bits);
118 return true;
119 }
120
121 void __intel_fb_flush(struct intel_frontbuffer *front,
122 enum fb_op_origin origin,
123 unsigned int frontbuffer_bits);
124
125 /**
126 * intel_frontbuffer_flush - flush frontbuffer object
127 * @front: GEM object to flush
128 * @origin: which operation caused the flush
129 *
130 * This function gets called every time rendering on the given object has
131 * completed and frontbuffer caching can be started again.
132 */
intel_frontbuffer_flush(struct intel_frontbuffer * front,enum fb_op_origin origin)133 static inline void intel_frontbuffer_flush(struct intel_frontbuffer *front,
134 enum fb_op_origin origin)
135 {
136 unsigned int frontbuffer_bits;
137
138 if (!front)
139 return;
140
141 frontbuffer_bits = atomic_read(&front->bits);
142 if (!frontbuffer_bits)
143 return;
144
145 __intel_fb_flush(front, origin, frontbuffer_bits);
146 }
147
148 void intel_frontbuffer_track(struct intel_frontbuffer *old,
149 struct intel_frontbuffer *new,
150 unsigned int frontbuffer_bits);
151
152 #endif /* __INTEL_FRONTBUFFER_H__ */
153