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
17struct drm_mode_create_dumb;
18struct drm_plane;
19struct drm_plane_state;
20struct drm_simple_display_pipe;
21struct filp;
22struct 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 %TTM_PL_VRAM
37 *		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 */
52struct drm_gem_vram_object {
53	struct ttm_buffer_object bo;
54	struct iosys_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 */
75static 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 */
87static 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
93struct drm_gem_vram_object *drm_gem_vram_create(struct drm_device *dev,
94						size_t size,
95						unsigned long pg_align);
96void drm_gem_vram_put(struct drm_gem_vram_object *gbo);
97s64 drm_gem_vram_offset(struct drm_gem_vram_object *gbo);
98int drm_gem_vram_pin(struct drm_gem_vram_object *gbo, unsigned long pl_flag);
99int drm_gem_vram_unpin(struct drm_gem_vram_object *gbo);
100int drm_gem_vram_vmap(struct drm_gem_vram_object *gbo, struct iosys_map *map);
101void drm_gem_vram_vunmap(struct drm_gem_vram_object *gbo,
102			 struct iosys_map *map);
103
104int drm_gem_vram_fill_create_dumb(struct drm_file *file,
105				  struct drm_device *dev,
106				  unsigned long pg_align,
107				  unsigned long pitch_align,
108				  struct drm_mode_create_dumb *args);
109
110/*
111 * Helpers for struct drm_driver
112 */
113
114int drm_gem_vram_driver_dumb_create(struct drm_file *file,
115				    struct drm_device *dev,
116				    struct drm_mode_create_dumb *args);
117
118/*
119 * Helpers for struct drm_plane_helper_funcs
120 */
121int
122drm_gem_vram_plane_helper_prepare_fb(struct drm_plane *plane,
123				     struct drm_plane_state *new_state);
124void
125drm_gem_vram_plane_helper_cleanup_fb(struct drm_plane *plane,
126				     struct drm_plane_state *old_state);
127
128/**
129 * DRM_GEM_VRAM_PLANE_HELPER_FUNCS - Initializes struct drm_plane_helper_funcs
130 *				     for VRAM handling
131 *
132 * Drivers may use GEM BOs as VRAM helpers for the framebuffer memory. This
133 * macro initializes struct drm_plane_helper_funcs to use the respective helper
134 * functions.
135 */
136#define DRM_GEM_VRAM_PLANE_HELPER_FUNCS \
137	.prepare_fb = drm_gem_vram_plane_helper_prepare_fb, \
138	.cleanup_fb = drm_gem_vram_plane_helper_cleanup_fb
139
140/*
141 * Helpers for struct drm_simple_display_pipe_funcs
142 */
143
144int drm_gem_vram_simple_display_pipe_prepare_fb(
145	struct drm_simple_display_pipe *pipe,
146	struct drm_plane_state *new_state);
147
148void drm_gem_vram_simple_display_pipe_cleanup_fb(
149	struct drm_simple_display_pipe *pipe,
150	struct drm_plane_state *old_state);
151
152/**
153 * define DRM_GEM_VRAM_DRIVER - default callback functions for
154 *				&struct drm_driver
155 *
156 * Drivers that use VRAM MM and GEM VRAM can use this macro to initialize
157 * &struct drm_driver with default functions.
158 */
159#define DRM_GEM_VRAM_DRIVER \
160	.debugfs_init	 = drm_vram_mm_debugfs_init, \
161	.dumb_create	 = drm_gem_vram_driver_dumb_create, \
162	.dumb_map_offset = drm_gem_ttm_dumb_map_offset
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 */
180struct 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() - Returns the container of type &struct ttm_device for
189 *			   field bdev.
190 * @bdev:	the TTM BO device
191 *
192 * Returns:
193 * The containing instance of &struct drm_vram_mm
194 */
195static 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
201void drm_vram_mm_debugfs_init(struct drm_minor *minor);
202
203/*
204 * Helpers for integration with struct drm_device
205 */
206
207int 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
214enum drm_mode_status
215drm_vram_helper_mode_valid(struct drm_device *dev,
216			   const struct drm_display_mode *mode);
217
218#endif
219