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_ioctl.h>
9#include <drm/drm_modes.h>
10#include <drm/ttm/ttm_bo_api.h>
11#include <drm/ttm/ttm_bo_driver.h>
12
13#include <linux/kernel.h> /* for container_of() */
14
15struct drm_mode_create_dumb;
16struct drm_plane;
17struct drm_plane_state;
18struct drm_simple_display_pipe;
19struct filp;
20struct vm_area_struct;
21
22#define DRM_GEM_VRAM_PL_FLAG_SYSTEM	(1 << 0)
23#define DRM_GEM_VRAM_PL_FLAG_VRAM	(1 << 1)
24#define DRM_GEM_VRAM_PL_FLAG_TOPDOWN	(1 << 2)
25
26/*
27 * Buffer-object helpers
28 */
29
30/**
31 * struct drm_gem_vram_object - GEM object backed by VRAM
32 * @gem:	GEM object
33 * @bo:		TTM buffer object
34 * @kmap:	Mapping information for @bo
35 * @placement:	TTM placement information. Supported placements are \
36	%TTM_PL_VRAM and %TTM_PL_SYSTEM
37 * @placements:	TTM placement information.
38 * @pin_count:	Pin counter
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 */
52struct drm_gem_vram_object {
53	struct ttm_buffer_object bo;
54	struct ttm_bo_kmap_obj kmap;
55
56	/**
57	 * @kmap_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 kmap_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	int pin_count;
69};
70
71/**
72 * Returns the container of type &struct drm_gem_vram_object
73 * for field bo.
74 * @bo:		the VRAM buffer object
75 * Returns:	The containing GEM VRAM object
76 */
77static inline struct drm_gem_vram_object *drm_gem_vram_of_bo(
78	struct ttm_buffer_object *bo)
79{
80	return container_of(bo, struct drm_gem_vram_object, bo);
81}
82
83/**
84 * Returns the container of type &struct drm_gem_vram_object
85 * for field gem.
86 * @gem:	the GEM object
87 * Returns:	The containing GEM VRAM object
88 */
89static inline struct drm_gem_vram_object *drm_gem_vram_of_gem(
90	struct drm_gem_object *gem)
91{
92	return container_of(gem, struct drm_gem_vram_object, bo.base);
93}
94
95struct drm_gem_vram_object *drm_gem_vram_create(struct drm_device *dev,
96						size_t size,
97						unsigned long pg_align);
98void drm_gem_vram_put(struct drm_gem_vram_object *gbo);
99u64 drm_gem_vram_mmap_offset(struct drm_gem_vram_object *gbo);
100s64 drm_gem_vram_offset(struct drm_gem_vram_object *gbo);
101int drm_gem_vram_pin(struct drm_gem_vram_object *gbo, unsigned long pl_flag);
102int drm_gem_vram_unpin(struct drm_gem_vram_object *gbo);
103void *drm_gem_vram_vmap(struct drm_gem_vram_object *gbo);
104void drm_gem_vram_vunmap(struct drm_gem_vram_object *gbo, void *vaddr);
105
106int drm_gem_vram_fill_create_dumb(struct drm_file *file,
107				  struct drm_device *dev,
108				  unsigned long pg_align,
109				  unsigned long pitch_align,
110				  struct drm_mode_create_dumb *args);
111
112/*
113 * Helpers for struct drm_driver
114 */
115
116int drm_gem_vram_driver_dumb_create(struct drm_file *file,
117				    struct drm_device *dev,
118				    struct drm_mode_create_dumb *args);
119int drm_gem_vram_driver_dumb_mmap_offset(struct drm_file *file,
120					 struct drm_device *dev,
121					 uint32_t handle, uint64_t *offset);
122
123/*
124 * Helpers for struct drm_plane_helper_funcs
125 */
126int
127drm_gem_vram_plane_helper_prepare_fb(struct drm_plane *plane,
128				     struct drm_plane_state *new_state);
129void
130drm_gem_vram_plane_helper_cleanup_fb(struct drm_plane *plane,
131				     struct drm_plane_state *old_state);
132
133/*
134 * Helpers for struct drm_simple_display_pipe_funcs
135 */
136
137int drm_gem_vram_simple_display_pipe_prepare_fb(
138	struct drm_simple_display_pipe *pipe,
139	struct drm_plane_state *new_state);
140
141void drm_gem_vram_simple_display_pipe_cleanup_fb(
142	struct drm_simple_display_pipe *pipe,
143	struct drm_plane_state *old_state);
144
145/**
146 * define DRM_GEM_VRAM_DRIVER - default callback functions for \
147	&struct drm_driver
148 *
149 * Drivers that use VRAM MM and GEM VRAM can use this macro to initialize
150 * &struct drm_driver with default functions.
151 */
152#define DRM_GEM_VRAM_DRIVER \
153	.debugfs_init             = drm_vram_mm_debugfs_init, \
154	.dumb_create		  = drm_gem_vram_driver_dumb_create, \
155	.dumb_map_offset	  = drm_gem_vram_driver_dumb_mmap_offset, \
156	.gem_prime_mmap		  = drm_gem_prime_mmap
157
158/*
159 *  VRAM memory manager
160 */
161
162/**
163 * struct drm_vram_mm - An instance of VRAM MM
164 * @vram_base:	Base address of the managed video memory
165 * @vram_size:	Size of the managed video memory in bytes
166 * @bdev:	The TTM BO device.
167 * @funcs:	TTM BO functions
168 *
169 * The fields &struct drm_vram_mm.vram_base and
170 * &struct drm_vram_mm.vrm_size are managed by VRAM MM, but are
171 * available for public read access. Use the field
172 * &struct drm_vram_mm.bdev to access the TTM BO device.
173 */
174struct drm_vram_mm {
175	uint64_t vram_base;
176	size_t vram_size;
177
178	struct ttm_bo_device bdev;
179};
180
181/**
182 * drm_vram_mm_of_bdev() - \
183	Returns the container of type &struct ttm_bo_device for field bdev.
184 * @bdev:	the TTM BO device
185 *
186 * Returns:
187 * The containing instance of &struct drm_vram_mm
188 */
189static inline struct drm_vram_mm *drm_vram_mm_of_bdev(
190	struct ttm_bo_device *bdev)
191{
192	return container_of(bdev, struct drm_vram_mm, bdev);
193}
194
195void drm_vram_mm_debugfs_init(struct drm_minor *minor);
196
197/*
198 * Helpers for integration with struct drm_device
199 */
200
201struct drm_vram_mm *drm_vram_helper_alloc_mm(
202	struct drm_device *dev, uint64_t vram_base, size_t vram_size);
203void drm_vram_helper_release_mm(struct drm_device *dev);
204
205int drmm_vram_helper_init(struct drm_device *dev, uint64_t vram_base,
206			  size_t vram_size);
207
208/*
209 * Mode-config helpers
210 */
211
212enum drm_mode_status
213drm_vram_helper_mode_valid(struct drm_device *dev,
214			   const struct drm_display_mode *mode);
215
216#endif
217