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