xref: /linux/drivers/gpu/drm/i915/display/intel_frontbuffer.h (revision 03c11eb3b16dc0058589751dfd91f254be2be613)
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/bits.h>
29 #include <linux/kref.h>
30 
31 #include "i915_active_types.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 	struct work_struct flush_work;
51 };
52 
53 /*
54  * Frontbuffer tracking bits. Set in obj->frontbuffer_bits while a gem bo is
55  * considered to be the frontbuffer for the given plane interface-wise. This
56  * doesn't mean that the hw necessarily already scans it out, but that any
57  * rendering (by the cpu or gpu) will land in the frontbuffer eventually.
58  *
59  * We have one bit per pipe and per scanout plane type.
60  */
61 #define INTEL_FRONTBUFFER_BITS_PER_PIPE 8
62 #define INTEL_FRONTBUFFER(pipe, plane_id) \
63 	BIT((plane_id) + INTEL_FRONTBUFFER_BITS_PER_PIPE * (pipe));
64 #define INTEL_FRONTBUFFER_OVERLAY(pipe) \
65 	BIT(INTEL_FRONTBUFFER_BITS_PER_PIPE - 1 + INTEL_FRONTBUFFER_BITS_PER_PIPE * (pipe))
66 #define INTEL_FRONTBUFFER_ALL_MASK(pipe) \
67 	GENMASK(INTEL_FRONTBUFFER_BITS_PER_PIPE * ((pipe) + 1) - 1,	\
68 		INTEL_FRONTBUFFER_BITS_PER_PIPE * (pipe))
69 
70 void intel_frontbuffer_flip_prepare(struct drm_i915_private *i915,
71 				    unsigned frontbuffer_bits);
72 void intel_frontbuffer_flip_complete(struct drm_i915_private *i915,
73 				     unsigned frontbuffer_bits);
74 void intel_frontbuffer_flip(struct drm_i915_private *i915,
75 			    unsigned frontbuffer_bits);
76 
77 void intel_frontbuffer_put(struct intel_frontbuffer *front);
78 
79 struct intel_frontbuffer *
80 intel_frontbuffer_get(struct drm_i915_gem_object *obj);
81 
82 void __intel_fb_invalidate(struct intel_frontbuffer *front,
83 			   enum fb_op_origin origin,
84 			   unsigned int frontbuffer_bits);
85 
86 /**
87  * intel_frontbuffer_invalidate - invalidate frontbuffer object
88  * @front: GEM object to invalidate
89  * @origin: which operation caused the invalidation
90  *
91  * This function gets called every time rendering on the given object starts and
92  * frontbuffer caching (fbc, low refresh rate for DRRS, panel self refresh) must
93  * be invalidated. For ORIGIN_CS any subsequent invalidation will be delayed
94  * until the rendering completes or a flip on this frontbuffer plane is
95  * scheduled.
96  */
intel_frontbuffer_invalidate(struct intel_frontbuffer * front,enum fb_op_origin origin)97 static inline bool intel_frontbuffer_invalidate(struct intel_frontbuffer *front,
98 						enum fb_op_origin origin)
99 {
100 	unsigned int frontbuffer_bits;
101 
102 	if (!front)
103 		return false;
104 
105 	frontbuffer_bits = atomic_read(&front->bits);
106 	if (!frontbuffer_bits)
107 		return false;
108 
109 	__intel_fb_invalidate(front, origin, frontbuffer_bits);
110 	return true;
111 }
112 
113 void __intel_fb_flush(struct intel_frontbuffer *front,
114 		      enum fb_op_origin origin,
115 		      unsigned int frontbuffer_bits);
116 
117 /**
118  * intel_frontbuffer_flush - flush frontbuffer object
119  * @front: GEM object to flush
120  * @origin: which operation caused the flush
121  *
122  * This function gets called every time rendering on the given object has
123  * completed and frontbuffer caching can be started again.
124  */
intel_frontbuffer_flush(struct intel_frontbuffer * front,enum fb_op_origin origin)125 static inline void intel_frontbuffer_flush(struct intel_frontbuffer *front,
126 					   enum fb_op_origin origin)
127 {
128 	unsigned int frontbuffer_bits;
129 
130 	if (!front)
131 		return;
132 
133 	frontbuffer_bits = atomic_read(&front->bits);
134 	if (!frontbuffer_bits)
135 		return;
136 
137 	__intel_fb_flush(front, origin, frontbuffer_bits);
138 }
139 
140 void intel_frontbuffer_queue_flush(struct intel_frontbuffer *front);
141 
142 void intel_frontbuffer_track(struct intel_frontbuffer *old,
143 			     struct intel_frontbuffer *new,
144 			     unsigned int frontbuffer_bits);
145 
146 #endif /* __INTEL_FRONTBUFFER_H__ */
147