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
 33struct drm_i915_private;
 34
 35enum fb_op_origin {
 36	ORIGIN_CPU = 0,
 37	ORIGIN_CS,
 38	ORIGIN_FLIP,
 39	ORIGIN_DIRTYFB,
 40	ORIGIN_CURSOR_UPDATE,
 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	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
 70void intel_frontbuffer_flip_prepare(struct drm_i915_private *i915,
 71				    unsigned frontbuffer_bits);
 72void intel_frontbuffer_flip_complete(struct drm_i915_private *i915,
 73				     unsigned frontbuffer_bits);
 74void intel_frontbuffer_flip(struct drm_i915_private *i915,
 75			    unsigned frontbuffer_bits);
 76
 77void intel_frontbuffer_put(struct intel_frontbuffer *front);
 78
 79struct intel_frontbuffer *
 80intel_frontbuffer_get(struct drm_i915_gem_object *obj);
 81
 82void __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 */
 97static 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
113void __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 */
125static 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
140void intel_frontbuffer_queue_flush(struct intel_frontbuffer *front);
141
142void intel_frontbuffer_track(struct intel_frontbuffer *old,
143			     struct intel_frontbuffer *new,
144			     unsigned int frontbuffer_bits);
145
146#endif /* __INTEL_FRONTBUFFER_H__ */