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 "i915_active.h"
31 
32 struct drm_i915_private;
33 struct drm_i915_gem_object;
34 
35 enum fb_op_origin {
36 	ORIGIN_GTT,
37 	ORIGIN_CPU,
38 	ORIGIN_CS,
39 	ORIGIN_FLIP,
40 	ORIGIN_DIRTYFB,
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 };
49 
50 void intel_frontbuffer_flip_prepare(struct drm_i915_private *i915,
51 				    unsigned frontbuffer_bits);
52 void intel_frontbuffer_flip_complete(struct drm_i915_private *i915,
53 				     unsigned frontbuffer_bits);
54 void intel_frontbuffer_flip(struct drm_i915_private *i915,
55 			    unsigned frontbuffer_bits);
56 
57 struct intel_frontbuffer *
58 intel_frontbuffer_get(struct drm_i915_gem_object *obj);
59 
60 void __intel_fb_invalidate(struct intel_frontbuffer *front,
61 			   enum fb_op_origin origin,
62 			   unsigned int frontbuffer_bits);
63 
64 /**
65  * intel_frontbuffer_invalidate - invalidate frontbuffer object
66  * @front: GEM object to invalidate
67  * @origin: which operation caused the invalidation
68  *
69  * This function gets called every time rendering on the given object starts and
70  * frontbuffer caching (fbc, low refresh rate for DRRS, panel self refresh) must
71  * be invalidated. For ORIGIN_CS any subsequent invalidation will be delayed
72  * until the rendering completes or a flip on this frontbuffer plane is
73  * scheduled.
74  */
75 static inline bool intel_frontbuffer_invalidate(struct intel_frontbuffer *front,
76 						enum fb_op_origin origin)
77 {
78 	unsigned int frontbuffer_bits;
79 
80 	if (!front)
81 		return false;
82 
83 	frontbuffer_bits = atomic_read(&front->bits);
84 	if (!frontbuffer_bits)
85 		return false;
86 
87 	__intel_fb_invalidate(front, origin, frontbuffer_bits);
88 	return true;
89 }
90 
91 void __intel_fb_flush(struct intel_frontbuffer *front,
92 		      enum fb_op_origin origin,
93 		      unsigned int frontbuffer_bits);
94 
95 /**
96  * intel_frontbuffer_flush - flush frontbuffer object
97  * @front: GEM object to flush
98  * @origin: which operation caused the flush
99  *
100  * This function gets called every time rendering on the given object has
101  * completed and frontbuffer caching can be started again.
102  */
103 static inline void intel_frontbuffer_flush(struct intel_frontbuffer *front,
104 					   enum fb_op_origin origin)
105 {
106 	unsigned int frontbuffer_bits;
107 
108 	if (!front)
109 		return;
110 
111 	frontbuffer_bits = atomic_read(&front->bits);
112 	if (!frontbuffer_bits)
113 		return;
114 
115 	__intel_fb_flush(front, origin, frontbuffer_bits);
116 }
117 
118 void intel_frontbuffer_track(struct intel_frontbuffer *old,
119 			     struct intel_frontbuffer *new,
120 			     unsigned int frontbuffer_bits);
121 
122 void intel_frontbuffer_put(struct intel_frontbuffer *front);
123 
124 #endif /* __INTEL_FRONTBUFFER_H__ */
125