LXR linux/drivers/gpu/drm/i915/display/intel

   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
  33struct drm_i915_private;
  34
  35enum fb_op_origin {
  36        ORIGIN_GTT,
  37        ORIGIN_CPU,
  38        ORIGIN_CS,
  39        ORIGIN_FLIP,
  40        ORIGIN_DIRTYFB,
  41};
  42
  43struct 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
  51void intel_frontbuffer_flip_prepare(struct drm_i915_private *i915,
  52                                    unsigned frontbuffer_bits);
  53void intel_frontbuffer_flip_complete(struct drm_i915_private *i915,
  54                                     unsigned frontbuffer_bits);
  55void intel_frontbuffer_flip(struct drm_i915_private *i915,
  56                            unsigned frontbuffer_bits);
  57
  58void intel_frontbuffer_put(struct intel_frontbuffer *front);
  59
  60static inline struct intel_frontbuffer *
  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
  87struct intel_frontbuffer *
  88intel_frontbuffer_get(struct drm_i915_gem_object *obj);
  89
  90void __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 */
 105static 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
 121void __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 */
 133static 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
 148void intel_frontbuffer_track(struct intel_frontbuffer *old,
 149                             struct intel_frontbuffer *new,
 150                             unsigned int frontbuffer_bits);
 151
 152#endif /* __INTEL_FRONTBUFFER_H__ */
 153