1 /* $NetBSD: intel_frontbuffer.h,v 1.2 2021/12/18 23:45:30 riastradh Exp $ */ 2 3 /* 4 * Copyright (c) 2014-2016 Intel Corporation 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the "Software"), 8 * to deal in the Software without restriction, including without limitation 9 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 10 * and/or sell copies of the Software, and to permit persons to whom the 11 * Software is furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice (including the next 14 * paragraph) shall be included in all copies or substantial portions of the 15 * Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 22 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 23 * IN THE SOFTWARE. 24 */ 25 26 #ifndef __INTEL_FRONTBUFFER_H__ 27 #define __INTEL_FRONTBUFFER_H__ 28 29 #include <linux/atomic.h> 30 #include <linux/kref.h> 31 32 #include "gem/i915_gem_object_types.h" 33 #include "i915_active.h" 34 35 struct drm_i915_private; 36 37 enum fb_op_origin { 38 ORIGIN_GTT, 39 ORIGIN_CPU, 40 ORIGIN_CS, 41 ORIGIN_FLIP, 42 ORIGIN_DIRTYFB, 43 }; 44 45 struct intel_frontbuffer { 46 struct kref ref; 47 atomic_t bits; 48 struct i915_active write; 49 struct drm_i915_gem_object *obj; 50 struct rcu_head rcu; 51 }; 52 53 void intel_frontbuffer_flip_prepare(struct drm_i915_private *i915, 54 unsigned frontbuffer_bits); 55 void intel_frontbuffer_flip_complete(struct drm_i915_private *i915, 56 unsigned frontbuffer_bits); 57 void intel_frontbuffer_flip(struct drm_i915_private *i915, 58 unsigned frontbuffer_bits); 59 60 void intel_frontbuffer_put(struct intel_frontbuffer *front); 61 62 static inline struct intel_frontbuffer * 63 __intel_frontbuffer_get(const struct drm_i915_gem_object *obj) 64 { 65 struct intel_frontbuffer *front; 66 67 if (likely(!rcu_access_pointer(obj->frontbuffer))) 68 return NULL; 69 70 rcu_read_lock(); 71 do { 72 front = rcu_dereference(obj->frontbuffer); 73 if (!front) 74 break; 75 76 if (unlikely(!kref_get_unless_zero(&front->ref))) 77 continue; 78 79 if (likely(front == rcu_access_pointer(obj->frontbuffer))) 80 break; 81 82 intel_frontbuffer_put(front); 83 } while (1); 84 rcu_read_unlock(); 85 86 return front; 87 } 88 89 struct intel_frontbuffer * 90 intel_frontbuffer_get(struct drm_i915_gem_object *obj); 91 92 void __intel_fb_invalidate(struct intel_frontbuffer *front, 93 enum fb_op_origin origin, 94 unsigned int frontbuffer_bits); 95 96 /** 97 * intel_frontbuffer_invalidate - invalidate frontbuffer object 98 * @front: GEM object to invalidate 99 * @origin: which operation caused the invalidation 100 * 101 * This function gets called every time rendering on the given object starts and 102 * frontbuffer caching (fbc, low refresh rate for DRRS, panel self refresh) must 103 * be invalidated. For ORIGIN_CS any subsequent invalidation will be delayed 104 * until the rendering completes or a flip on this frontbuffer plane is 105 * scheduled. 106 */ 107 static inline bool intel_frontbuffer_invalidate(struct intel_frontbuffer *front, 108 enum fb_op_origin origin) 109 { 110 unsigned int frontbuffer_bits; 111 112 if (!front) 113 return false; 114 115 frontbuffer_bits = atomic_read(&front->bits); 116 if (!frontbuffer_bits) 117 return false; 118 119 __intel_fb_invalidate(front, origin, frontbuffer_bits); 120 return true; 121 } 122 123 void __intel_fb_flush(struct intel_frontbuffer *front, 124 enum fb_op_origin origin, 125 unsigned int frontbuffer_bits); 126 127 /** 128 * intel_frontbuffer_flush - flush frontbuffer object 129 * @front: GEM object to flush 130 * @origin: which operation caused the flush 131 * 132 * This function gets called every time rendering on the given object has 133 * completed and frontbuffer caching can be started again. 134 */ 135 static inline void intel_frontbuffer_flush(struct intel_frontbuffer *front, 136 enum fb_op_origin origin) 137 { 138 unsigned int frontbuffer_bits; 139 140 if (!front) 141 return; 142 143 frontbuffer_bits = atomic_read(&front->bits); 144 if (!frontbuffer_bits) 145 return; 146 147 __intel_fb_flush(front, origin, frontbuffer_bits); 148 } 149 150 void intel_frontbuffer_track(struct intel_frontbuffer *old, 151 struct intel_frontbuffer *new, 152 unsigned int frontbuffer_bits); 153 154 #endif /* __INTEL_FRONTBUFFER_H__ */ 155