1/*
2 * Copyright (c) 2016 Intel Corporation
3 *
4 * Permission to use, copy, modify, distribute, and sell this software and its
5 * documentation for any purpose is hereby granted without fee, provided that
6 * the above copyright notice appear in all copies and that both that copyright
7 * notice and this permission notice appear in supporting documentation, and
8 * that the name of the copyright holders not be used in advertising or
9 * publicity pertaining to distribution of the software without specific,
10 * written prior permission. The copyright holders make no representations
11 * about the suitability of this software for any purpose. It is provided "as
12 * is" without express or implied warranty.
13 *
14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20 * OF THIS SOFTWARE.
21 */
22
23#ifndef __DRM_FRAMEBUFFER_H__
24#define __DRM_FRAMEBUFFER_H__
25
26#include <linux/ctype.h>
27#include <linux/list.h>
28#include <linux/sched.h>
29
30#include <drm/drm_mode_object.h>
31
32struct drm_clip_rect;
33struct drm_device;
34struct drm_file;
35struct drm_framebuffer;
36struct drm_gem_object;
37
38/**
39 * struct drm_framebuffer_funcs - framebuffer hooks
40 */
41struct drm_framebuffer_funcs {
42 /**
43 * @destroy:
44 *
45 * Clean up framebuffer resources, specifically also unreference the
46 * backing storage. The core guarantees to call this function for every
47 * framebuffer successfully created by calling
48 * &drm_mode_config_funcs.fb_create. Drivers must also call
49 * drm_framebuffer_cleanup() to release DRM core resources for this
50 * framebuffer.
51 */
52 void (*destroy)(struct drm_framebuffer *framebuffer);
53
54 /**
55 * @create_handle:
56 *
57 * Create a buffer handle in the driver-specific buffer manager (either
58 * GEM or TTM) valid for the passed-in &struct drm_file. This is used by
59 * the core to implement the GETFB IOCTL, which returns (for
60 * sufficiently priviledged user) also a native buffer handle. This can
61 * be used for seamless transitions between modesetting clients by
62 * copying the current screen contents to a private buffer and blending
63 * between that and the new contents.
64 *
65 * GEM based drivers should call drm_gem_handle_create() to create the
66 * handle.
67 *
68 * RETURNS:
69 *
70 * 0 on success or a negative error code on failure.
71 */
72 int (*create_handle)(struct drm_framebuffer *fb,
73 struct drm_file *file_priv,
74 unsigned int *handle);
75 /**
76 * @dirty:
77 *
78 * Optional callback for the dirty fb IOCTL.
79 *
80 * Userspace can notify the driver via this callback that an area of the
81 * framebuffer has changed and should be flushed to the display
82 * hardware. This can also be used internally, e.g. by the fbdev
83 * emulation, though that's not the case currently.
84 *
85 * See documentation in drm_mode.h for the struct drm_mode_fb_dirty_cmd
86 * for more information as all the semantics and arguments have a one to
87 * one mapping on this function.
88 *
89 * RETURNS:
90 *
91 * 0 on success or a negative error code on failure.
92 */
93 int (*dirty)(struct drm_framebuffer *framebuffer,
94 struct drm_file *file_priv, unsigned flags,
95 unsigned color, struct drm_clip_rect *clips,
96 unsigned num_clips);
97};
98
99/**
100 * struct drm_framebuffer - frame buffer object
101 *
102 * Note that the fb is refcounted for the benefit of driver internals,
103 * for example some hw, disabling a CRTC/plane is asynchronous, and
104 * scanout does not actually complete until the next vblank. So some
105 * cleanup (like releasing the reference(s) on the backing GEM bo(s))
106 * should be deferred. In cases like this, the driver would like to
107 * hold a ref to the fb even though it has already been removed from
108 * userspace perspective. See drm_framebuffer_get() and
109 * drm_framebuffer_put().
110 *
111 * The refcount is stored inside the mode object @base.
112 */
113struct drm_framebuffer {
114 /**
115 * @dev: DRM device this framebuffer belongs to
116 */
117 struct drm_device *dev;
118 /**
119 * @head: Place on the &drm_mode_config.fb_list, access protected by
120 * &drm_mode_config.fb_lock.
121 */
122 struct list_head head;
123
124 /**
125 * @base: base modeset object structure, contains the reference count.
126 */
127 struct drm_mode_object base;
128
129 /**
130 * @comm: Name of the process allocating the fb, used for fb dumping.
131 */
132 char comm[TASK_COMM_LEN];
133
134 /**
135 * @format: framebuffer format information
136 */
137 const struct drm_format_info *format;
138 /**
139 * @funcs: framebuffer vfunc table
140 */
141 const struct drm_framebuffer_funcs *funcs;
142 /**
143 * @pitches: Line stride per buffer. For userspace created object this
144 * is copied from drm_mode_fb_cmd2.
145 */
146 unsigned int pitches[4];
147 /**
148 * @offsets: Offset from buffer start to the actual pixel data in bytes,
149 * per buffer. For userspace created object this is copied from
150 * drm_mode_fb_cmd2.
151 *
152 * Note that this is a linear offset and does not take into account
153 * tiling or buffer laytou per @modifier. It meant to be used when the
154 * actual pixel data for this framebuffer plane starts at an offset,
155 * e.g. when multiple planes are allocated within the same backing
156 * storage buffer object. For tiled layouts this generally means it
157 * @offsets must at least be tile-size aligned, but hardware often has
158 * stricter requirements.
159 *
160 * This should not be used to specifiy x/y pixel offsets into the buffer
161 * data (even for linear buffers). Specifying an x/y pixel offset is
162 * instead done through the source rectangle in &struct drm_plane_state.
163 */
164 unsigned int offsets[4];
165 /**
166 * @modifier: Data layout modifier. This is used to describe
167 * tiling, or also special layouts (like compression) of auxiliary
168 * buffers. For userspace created object this is copied from
169 * drm_mode_fb_cmd2.
170 */
171 uint64_t modifier;
172 /**
173 * @width: Logical width of the visible area of the framebuffer, in
174 * pixels.
175 */
176 unsigned int width;
177 /**
178 * @height: Logical height of the visible area of the framebuffer, in
179 * pixels.
180 */
181 unsigned int height;
182 /**
183 * @flags: Framebuffer flags like DRM_MODE_FB_INTERLACED or
184 * DRM_MODE_FB_MODIFIERS.
185 */
186 int flags;
187 /**
188 * @hot_x: X coordinate of the cursor hotspot. Used by the legacy cursor
189 * IOCTL when the driver supports cursor through a DRM_PLANE_TYPE_CURSOR
190 * universal plane.
191 */
192 int hot_x;
193 /**
194 * @hot_y: Y coordinate of the cursor hotspot. Used by the legacy cursor
195 * IOCTL when the driver supports cursor through a DRM_PLANE_TYPE_CURSOR
196 * universal plane.
197 */
198 int hot_y;
199 /**
200 * @filp_head: Placed on &drm_file.fbs, protected by &drm_file.fbs_lock.
201 */
202 struct list_head filp_head;
203 /**
204 * @obj: GEM objects backing the framebuffer, one per plane (optional).
205 *
206 * This is used by the GEM framebuffer helpers, see e.g.
207 * drm_gem_fb_create().
208 */
209 struct drm_gem_object *obj[4];
210};
211
212#define obj_to_fb(x) container_of(x, struct drm_framebuffer, base)
213
214int drm_framebuffer_init(struct drm_device *dev,
215 struct drm_framebuffer *fb,
216 const struct drm_framebuffer_funcs *funcs);
217struct drm_framebuffer *drm_framebuffer_lookup(struct drm_device *dev,
218 struct drm_file *file_priv,
219 uint32_t id);
220void drm_framebuffer_remove(struct drm_framebuffer *fb);
221void drm_framebuffer_cleanup(struct drm_framebuffer *fb);
222void drm_framebuffer_unregister_private(struct drm_framebuffer *fb);
223
224/**
225 * drm_framebuffer_get - acquire a framebuffer reference
226 * @fb: DRM framebuffer
227 *
228 * This function increments the framebuffer's reference count.
229 */
230static inline void drm_framebuffer_get(struct drm_framebuffer *fb)
231{
232 drm_mode_object_get(&fb->base);
233}
234
235/**
236 * drm_framebuffer_put - release a framebuffer reference
237 * @fb: DRM framebuffer
238 *
239 * This function decrements the framebuffer's reference count and frees the
240 * framebuffer if the reference count drops to zero.
241 */
242static inline void drm_framebuffer_put(struct drm_framebuffer *fb)
243{
244 drm_mode_object_put(&fb->base);
245}
246
247/**
248 * drm_framebuffer_read_refcount - read the framebuffer reference count.
249 * @fb: framebuffer
250 *
251 * This functions returns the framebuffer's reference count.
252 */
253static inline uint32_t drm_framebuffer_read_refcount(const struct drm_framebuffer *fb)
254{
255 return kref_read(&fb->base.refcount);
256}
257
258/**
259 * drm_framebuffer_assign - store a reference to the fb
260 * @p: location to store framebuffer
261 * @fb: new framebuffer (maybe NULL)
262 *
263 * This functions sets the location to store a reference to the framebuffer,
264 * unreferencing the framebuffer that was previously stored in that location.
265 */
266static inline void drm_framebuffer_assign(struct drm_framebuffer **p,
267 struct drm_framebuffer *fb)
268{
269 if (fb)
270 drm_framebuffer_get(fb);
271 if (*p)
272 drm_framebuffer_put(*p);
273 *p = fb;
274}
275
276/*
277 * drm_for_each_fb - iterate over all framebuffers
278 * @fb: the loop cursor
279 * @dev: the DRM device
280 *
281 * Iterate over all framebuffers of @dev. User must hold
282 * &drm_mode_config.fb_lock.
283 */
284#define drm_for_each_fb(fb, dev) \
285 for (WARN_ON(!mutex_is_locked(&(dev)->mode_config.fb_lock)), \
286 fb = list_first_entry(&(dev)->mode_config.fb_list, \
287 struct drm_framebuffer, head); \
288 &fb->head != (&(dev)->mode_config.fb_list); \
289 fb = list_next_entry(fb, head))
290
291int drm_framebuffer_plane_width(int width,
292 const struct drm_framebuffer *fb, int plane);
293int drm_framebuffer_plane_height(int height,
294 const struct drm_framebuffer *fb, int plane);
295
296#endif
297