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 "gem/i915_gem_object_types.h" 32 #include "i915_active_types.h" 33 34 struct drm_i915_private; 35 36 enum fb_op_origin { 37 ORIGIN_CPU = 0, 38 ORIGIN_CS, 39 ORIGIN_FLIP, 40 ORIGIN_DIRTYFB, 41 ORIGIN_CURSOR_UPDATE, 42 }; 43 44 struct intel_frontbuffer { 45 struct kref ref; 46 atomic_t bits; 47 struct i915_active write; 48 struct drm_i915_gem_object *obj; 49 struct rcu_head rcu; 50 }; 51 52 /* 53 * Frontbuffer tracking bits. Set in obj->frontbuffer_bits while a gem bo is 54 * considered to be the frontbuffer for the given plane interface-wise. This 55 * doesn't mean that the hw necessarily already scans it out, but that any 56 * rendering (by the cpu or gpu) will land in the frontbuffer eventually. 57 * 58 * We have one bit per pipe and per scanout plane type. 59 */ 60 #define INTEL_FRONTBUFFER_BITS_PER_PIPE 8 61 #define INTEL_FRONTBUFFER(pipe, plane_id) \ 62 BIT((plane_id) + INTEL_FRONTBUFFER_BITS_PER_PIPE * (pipe)); 63 #define INTEL_FRONTBUFFER_OVERLAY(pipe) \ 64 BIT(INTEL_FRONTBUFFER_BITS_PER_PIPE - 1 + INTEL_FRONTBUFFER_BITS_PER_PIPE * (pipe)) 65 #define INTEL_FRONTBUFFER_ALL_MASK(pipe) \ 66 GENMASK(INTEL_FRONTBUFFER_BITS_PER_PIPE * ((pipe) + 1) - 1, \ 67 INTEL_FRONTBUFFER_BITS_PER_PIPE * (pipe)) 68 69 void intel_frontbuffer_flip_prepare(struct drm_i915_private *i915, 70 unsigned frontbuffer_bits); 71 void intel_frontbuffer_flip_complete(struct drm_i915_private *i915, 72 unsigned frontbuffer_bits); 73 void intel_frontbuffer_flip(struct drm_i915_private *i915, 74 unsigned frontbuffer_bits); 75 76 void intel_frontbuffer_put(struct intel_frontbuffer *front); 77 78 static inline struct intel_frontbuffer * 79 __intel_frontbuffer_get(const struct drm_i915_gem_object *obj) 80 { 81 struct intel_frontbuffer *front; 82 83 if (likely(!rcu_access_pointer(obj->frontbuffer))) 84 return NULL; 85 86 rcu_read_lock(); 87 do { 88 front = rcu_dereference(obj->frontbuffer); 89 if (!front) 90 break; 91 92 if (unlikely(!kref_get_unless_zero(&front->ref))) 93 continue; 94 95 if (likely(front == rcu_access_pointer(obj->frontbuffer))) 96 break; 97 98 intel_frontbuffer_put(front); 99 } while (1); 100 rcu_read_unlock(); 101 102 return front; 103 } 104 105 struct intel_frontbuffer * 106 intel_frontbuffer_get(struct drm_i915_gem_object *obj); 107 108 void __intel_fb_invalidate(struct intel_frontbuffer *front, 109 enum fb_op_origin origin, 110 unsigned int frontbuffer_bits); 111 112 /** 113 * intel_frontbuffer_invalidate - invalidate frontbuffer object 114 * @front: GEM object to invalidate 115 * @origin: which operation caused the invalidation 116 * 117 * This function gets called every time rendering on the given object starts and 118 * frontbuffer caching (fbc, low refresh rate for DRRS, panel self refresh) must 119 * be invalidated. For ORIGIN_CS any subsequent invalidation will be delayed 120 * until the rendering completes or a flip on this frontbuffer plane is 121 * scheduled. 122 */ 123 static inline bool intel_frontbuffer_invalidate(struct intel_frontbuffer *front, 124 enum fb_op_origin origin) 125 { 126 unsigned int frontbuffer_bits; 127 128 if (!front) 129 return false; 130 131 frontbuffer_bits = atomic_read(&front->bits); 132 if (!frontbuffer_bits) 133 return false; 134 135 __intel_fb_invalidate(front, origin, frontbuffer_bits); 136 return true; 137 } 138 139 void __intel_fb_flush(struct intel_frontbuffer *front, 140 enum fb_op_origin origin, 141 unsigned int frontbuffer_bits); 142 143 /** 144 * intel_frontbuffer_flush - flush frontbuffer object 145 * @front: GEM object to flush 146 * @origin: which operation caused the flush 147 * 148 * This function gets called every time rendering on the given object has 149 * completed and frontbuffer caching can be started again. 150 */ 151 static inline void intel_frontbuffer_flush(struct intel_frontbuffer *front, 152 enum fb_op_origin origin) 153 { 154 unsigned int frontbuffer_bits; 155 156 if (!front) 157 return; 158 159 frontbuffer_bits = atomic_read(&front->bits); 160 if (!frontbuffer_bits) 161 return; 162 163 __intel_fb_flush(front, origin, frontbuffer_bits); 164 } 165 166 void intel_frontbuffer_track(struct intel_frontbuffer *old, 167 struct intel_frontbuffer *new, 168 unsigned int frontbuffer_bits); 169 170 #endif /* __INTEL_FRONTBUFFER_H__ */ 171