1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2
3 #ifndef DRM_GEM_VRAM_HELPER_H
4 #define DRM_GEM_VRAM_HELPER_H
5
6 #include <drm/drm_file.h>
7 #include <drm/drm_gem.h>
8 #include <drm/drm_gem_ttm_helper.h>
9 #include <drm/drm_ioctl.h>
10 #include <drm/drm_modes.h>
11 #include <drm/ttm/ttm_bo_api.h>
12 #include <drm/ttm/ttm_bo_driver.h>
13
14 #include <linux/dma-buf-map.h>
15 #include <linux/kernel.h> /* for container_of() */
16
17 struct drm_mode_create_dumb;
18 struct drm_plane;
19 struct drm_plane_state;
20 struct drm_simple_display_pipe;
21 struct filp;
22 struct vm_area_struct;
23
24 #define DRM_GEM_VRAM_PL_FLAG_SYSTEM (1 << 0)
25 #define DRM_GEM_VRAM_PL_FLAG_VRAM (1 << 1)
26 #define DRM_GEM_VRAM_PL_FLAG_TOPDOWN (1 << 2)
27
28 /*
29 * Buffer-object helpers
30 */
31
32 /**
33 * struct drm_gem_vram_object - GEM object backed by VRAM
34 * @bo: TTM buffer object
35 * @map: Mapping information for @bo
36 * @placement: TTM placement information. Supported placements are \
37 %TTM_PL_VRAM and %TTM_PL_SYSTEM
38 * @placements: TTM placement information.
39 *
40 * The type struct drm_gem_vram_object represents a GEM object that is
41 * backed by VRAM. It can be used for simple framebuffer devices with
42 * dedicated memory. The buffer object can be evicted to system memory if
43 * video memory becomes scarce.
44 *
45 * GEM VRAM objects perform reference counting for pin and mapping
46 * operations. So a buffer object that has been pinned N times with
47 * drm_gem_vram_pin() must be unpinned N times with
48 * drm_gem_vram_unpin(). The same applies to pairs of
49 * drm_gem_vram_kmap() and drm_gem_vram_kunmap(), as well as pairs of
50 * drm_gem_vram_vmap() and drm_gem_vram_vunmap().
51 */
52 struct drm_gem_vram_object {
53 struct ttm_buffer_object bo;
54 struct dma_buf_map map;
55
56 /**
57 * @vmap_use_count:
58 *
59 * Reference count on the virtual address.
60 * The address are un-mapped when the count reaches zero.
61 */
62 unsigned int vmap_use_count;
63
64 /* Supported placements are %TTM_PL_VRAM and %TTM_PL_SYSTEM */
65 struct ttm_placement placement;
66 struct ttm_place placements[2];
67 };
68
69 /**
70 * drm_gem_vram_of_bo - Returns the container of type
71 * &struct drm_gem_vram_object for field bo.
72 * @bo: the VRAM buffer object
73 * Returns: The containing GEM VRAM object
74 */
drm_gem_vram_of_bo(struct ttm_buffer_object * bo)75 static inline struct drm_gem_vram_object *drm_gem_vram_of_bo(
76 struct ttm_buffer_object *bo)
77 {
78 return container_of(bo, struct drm_gem_vram_object, bo);
79 }
80
81 /**
82 * drm_gem_vram_of_gem - Returns the container of type
83 * &struct drm_gem_vram_object for field gem.
84 * @gem: the GEM object
85 * Returns: The containing GEM VRAM object
86 */
drm_gem_vram_of_gem(struct drm_gem_object * gem)87 static inline struct drm_gem_vram_object *drm_gem_vram_of_gem(
88 struct drm_gem_object *gem)
89 {
90 return container_of(gem, struct drm_gem_vram_object, bo.base);
91 }
92
93 struct drm_gem_vram_object *drm_gem_vram_create(struct drm_device *dev,
94 size_t size,
95 unsigned long pg_align);
96 void drm_gem_vram_put(struct drm_gem_vram_object *gbo);
97 s64 drm_gem_vram_offset(struct drm_gem_vram_object *gbo);
98 int drm_gem_vram_pin(struct drm_gem_vram_object *gbo, unsigned long pl_flag);
99 int drm_gem_vram_unpin(struct drm_gem_vram_object *gbo);
100 int drm_gem_vram_vmap(struct drm_gem_vram_object *gbo, struct dma_buf_map *map);
101 void drm_gem_vram_vunmap(struct drm_gem_vram_object *gbo, struct dma_buf_map *map);
102
103 int drm_gem_vram_fill_create_dumb(struct drm_file *file,
104 struct drm_device *dev,
105 unsigned long pg_align,
106 unsigned long pitch_align,
107 struct drm_mode_create_dumb *args);
108
109 /*
110 * Helpers for struct drm_driver
111 */
112
113 int drm_gem_vram_driver_dumb_create(struct drm_file *file,
114 struct drm_device *dev,
115 struct drm_mode_create_dumb *args);
116
117 /*
118 * Helpers for struct drm_plane_helper_funcs
119 */
120 int
121 drm_gem_vram_plane_helper_prepare_fb(struct drm_plane *plane,
122 struct drm_plane_state *new_state);
123 void
124 drm_gem_vram_plane_helper_cleanup_fb(struct drm_plane *plane,
125 struct drm_plane_state *old_state);
126
127 /**
128 * DRM_GEM_VRAM_PLANE_HELPER_FUNCS -
129 * Initializes struct drm_plane_helper_funcs for VRAM handling
130 *
131 * Drivers may use GEM BOs as VRAM helpers for the framebuffer memory. This
132 * macro initializes struct drm_plane_helper_funcs to use the respective helper
133 * functions.
134 */
135 #define DRM_GEM_VRAM_PLANE_HELPER_FUNCS \
136 .prepare_fb = drm_gem_vram_plane_helper_prepare_fb, \
137 .cleanup_fb = drm_gem_vram_plane_helper_cleanup_fb
138
139 /*
140 * Helpers for struct drm_simple_display_pipe_funcs
141 */
142
143 int drm_gem_vram_simple_display_pipe_prepare_fb(
144 struct drm_simple_display_pipe *pipe,
145 struct drm_plane_state *new_state);
146
147 void drm_gem_vram_simple_display_pipe_cleanup_fb(
148 struct drm_simple_display_pipe *pipe,
149 struct drm_plane_state *old_state);
150
151 /**
152 * define DRM_GEM_VRAM_DRIVER - default callback functions for \
153 &struct drm_driver
154 *
155 * Drivers that use VRAM MM and GEM VRAM can use this macro to initialize
156 * &struct drm_driver with default functions.
157 */
158 #define DRM_GEM_VRAM_DRIVER \
159 .debugfs_init = drm_vram_mm_debugfs_init, \
160 .dumb_create = drm_gem_vram_driver_dumb_create, \
161 .dumb_map_offset = drm_gem_ttm_dumb_map_offset, \
162 .gem_prime_mmap = drm_gem_prime_mmap
163
164 /*
165 * VRAM memory manager
166 */
167
168 /**
169 * struct drm_vram_mm - An instance of VRAM MM
170 * @vram_base: Base address of the managed video memory
171 * @vram_size: Size of the managed video memory in bytes
172 * @bdev: The TTM BO device.
173 * @funcs: TTM BO functions
174 *
175 * The fields &struct drm_vram_mm.vram_base and
176 * &struct drm_vram_mm.vrm_size are managed by VRAM MM, but are
177 * available for public read access. Use the field
178 * &struct drm_vram_mm.bdev to access the TTM BO device.
179 */
180 struct drm_vram_mm {
181 uint64_t vram_base;
182 size_t vram_size;
183
184 struct ttm_device bdev;
185 };
186
187 /**
188 * drm_vram_mm_of_bdev() - \
189 Returns the container of type &struct ttm_device for field bdev.
190 * @bdev: the TTM BO device
191 *
192 * Returns:
193 * The containing instance of &struct drm_vram_mm
194 */
drm_vram_mm_of_bdev(struct ttm_device * bdev)195 static inline struct drm_vram_mm *drm_vram_mm_of_bdev(
196 struct ttm_device *bdev)
197 {
198 return container_of(bdev, struct drm_vram_mm, bdev);
199 }
200
201 void drm_vram_mm_debugfs_init(struct drm_minor *minor);
202
203 /*
204 * Helpers for integration with struct drm_device
205 */
206
207 int drmm_vram_helper_init(struct drm_device *dev, uint64_t vram_base,
208 size_t vram_size);
209
210 /*
211 * Mode-config helpers
212 */
213
214 enum drm_mode_status
215 drm_vram_helper_mode_valid(struct drm_device *dev,
216 const struct drm_display_mode *mode);
217
218 #endif
219