1/*
2 * Copyright 2020 Advanced Micro Devices, Inc.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20 * OTHER DEALINGS IN THE SOFTWARE.
21 *
22 * Authors: Christian König
23 */
24
25#ifndef _TTM_DEVICE_H_
26#define _TTM_DEVICE_H_
27
28#include <linux/types.h>
29#include <linux/workqueue.h>
30#include <drm/ttm/ttm_resource.h>
31#include <drm/ttm/ttm_pool.h>
32
33struct ttm_device;
34struct ttm_placement;
35struct ttm_buffer_object;
36struct ttm_operation_ctx;
37
38/**
39 * struct ttm_global - Buffer object driver global data.
40 */
41extern struct ttm_global {
42
43 /**
44 * @dummy_read_page: Pointer to a dummy page used for mapping requests
45 * of unpopulated pages. Constant after init.
46 */
47 struct page *dummy_read_page;
48
49 /**
50 * @device_list: List of buffer object devices. Protected by
51 * ttm_global_mutex.
52 */
53 struct list_head device_list;
54
55 /**
56 * @bo_count: Number of buffer objects allocated by devices.
57 */
58 atomic_t bo_count;
59} ttm_glob;
60
61struct ttm_device_funcs {
62 /**
63 * ttm_tt_create
64 *
65 * @bo: The buffer object to create the ttm for.
66 * @page_flags: Page flags as identified by TTM_TT_FLAG_XX flags.
67 *
68 * Create a struct ttm_tt to back data with system memory pages.
69 * No pages are actually allocated.
70 * Returns:
71 * NULL: Out of memory.
72 */
73 struct ttm_tt *(*ttm_tt_create)(struct ttm_buffer_object *bo,
74 uint32_t page_flags);
75
76 /**
77 * ttm_tt_populate
78 *
79 * @ttm: The struct ttm_tt to contain the backing pages.
80 *
81 * Allocate all backing pages
82 * Returns:
83 * -ENOMEM: Out of memory.
84 */
85 int (*ttm_tt_populate)(struct ttm_device *bdev,
86 struct ttm_tt *ttm,
87 struct ttm_operation_ctx *ctx);
88
89 /**
90 * ttm_tt_unpopulate
91 *
92 * @ttm: The struct ttm_tt to contain the backing pages.
93 *
94 * Free all backing page
95 */
96 void (*ttm_tt_unpopulate)(struct ttm_device *bdev,
97 struct ttm_tt *ttm);
98
99 /**
100 * ttm_tt_destroy
101 *
102 * @bdev: Pointer to a ttm device
103 * @ttm: Pointer to a struct ttm_tt.
104 *
105 * Destroy the backend. This will be call back from ttm_tt_destroy so
106 * don't call ttm_tt_destroy from the callback or infinite loop.
107 */
108 void (*ttm_tt_destroy)(struct ttm_device *bdev, struct ttm_tt *ttm);
109
110 /**
111 * struct ttm_bo_driver member eviction_valuable
112 *
113 * @bo: the buffer object to be evicted
114 * @place: placement we need room for
115 *
116 * Check with the driver if it is valuable to evict a BO to make room
117 * for a certain placement.
118 */
119 bool (*eviction_valuable)(struct ttm_buffer_object *bo,
120 const struct ttm_place *place);
121 /**
122 * struct ttm_bo_driver member evict_flags:
123 *
124 * @bo: the buffer object to be evicted
125 *
126 * Return the bo flags for a buffer which is not mapped to the hardware.
127 * These will be placed in proposed_flags so that when the move is
128 * finished, they'll end up in bo->mem.flags
129 * This should not cause multihop evictions, and the core will warn
130 * if one is proposed.
131 */
132
133 void (*evict_flags)(struct ttm_buffer_object *bo,
134 struct ttm_placement *placement);
135
136 /**
137 * struct ttm_bo_driver member move:
138 *
139 * @bo: the buffer to move
140 * @evict: whether this motion is evicting the buffer from
141 * the graphics address space
142 * @ctx: context for this move with parameters
143 * @new_mem: the new memory region receiving the buffer
144 * @hop: placement for driver directed intermediate hop
145 *
146 * Move a buffer between two memory regions.
147 * Returns errno -EMULTIHOP if driver requests a hop
148 */
149 int (*move)(struct ttm_buffer_object *bo, bool evict,
150 struct ttm_operation_ctx *ctx,
151 struct ttm_resource *new_mem,
152 struct ttm_place *hop);
153
154 /**
155 * Hook to notify driver about a resource delete.
156 */
157 void (*delete_mem_notify)(struct ttm_buffer_object *bo);
158
159 /**
160 * notify the driver that we're about to swap out this bo
161 */
162 void (*swap_notify)(struct ttm_buffer_object *bo);
163
164 /**
165 * Driver callback on when mapping io memory (for bo_move_memcpy
166 * for instance). TTM will take care to call io_mem_free whenever
167 * the mapping is not use anymore. io_mem_reserve & io_mem_free
168 * are balanced.
169 */
170 int (*io_mem_reserve)(struct ttm_device *bdev,
171 struct ttm_resource *mem);
172 void (*io_mem_free)(struct ttm_device *bdev,
173 struct ttm_resource *mem);
174
175 /**
176 * Return the pfn for a given page_offset inside the BO.
177 *
178 * @bo: the BO to look up the pfn for
179 * @page_offset: the offset to look up
180 */
181 unsigned long (*io_mem_pfn)(struct ttm_buffer_object *bo,
182 unsigned long page_offset);
183
184 /**
185 * Read/write memory buffers for ptrace access
186 *
187 * @bo: the BO to access
188 * @offset: the offset from the start of the BO
189 * @buf: pointer to source/destination buffer
190 * @len: number of bytes to copy
191 * @write: whether to read (0) from or write (non-0) to BO
192 *
193 * If successful, this function should return the number of
194 * bytes copied, -EIO otherwise. If the number of bytes
195 * returned is < len, the function may be called again with
196 * the remainder of the buffer to copy.
197 */
198 int (*access_memory)(struct ttm_buffer_object *bo, unsigned long offset,
199 void *buf, int len, int write);
200
201 /**
202 * Notify the driver that we're about to release a BO
203 *
204 * @bo: BO that is about to be released
205 *
206 * Gives the driver a chance to do any cleanup, including
207 * adding fences that may force a delayed delete
208 */
209 void (*release_notify)(struct ttm_buffer_object *bo);
210};
211
212/**
213 * struct ttm_device - Buffer object driver device-specific data.
214 */
215struct ttm_device {
216 /**
217 * @device_list: Our entry in the global device list.
218 * Constant after bo device init
219 */
220 struct list_head device_list;
221
222 /**
223 * @funcs: Function table for the device.
224 * Constant after bo device init
225 */
226 const struct ttm_device_funcs *funcs;
227
228 /**
229 * @sysman: Resource manager for the system domain.
230 * Access via ttm_manager_type.
231 */
232 struct ttm_resource_manager sysman;
233
234 /**
235 * @man_drv: An array of resource_managers, one per resource type.
236 */
237 struct ttm_resource_manager *man_drv[TTM_NUM_MEM_TYPES];
238
239 /**
240 * @vma_manager: Address space manager for finding BOs to mmap.
241 */
242 struct drm_vma_offset_manager *vma_manager;
243
244 /**
245 * @pool: page pool for the device.
246 */
247 struct ttm_pool pool;
248
249 /**
250 * @lru_lock: Protection for the per manager LRU and ddestroy lists.
251 */
252 spinlock_t lru_lock;
253
254 /**
255 * @unevictable: Buffer objects which are pinned or swapped and as such
256 * not on an LRU list.
257 */
258 struct list_head unevictable;
259
260 /**
261 * @dev_mapping: A pointer to the struct address_space for invalidating
262 * CPU mappings on buffer move. Protected by load/unload sync.
263 */
264 struct address_space *dev_mapping;
265
266 /**
267 * @wq: Work queue structure for the delayed delete workqueue.
268 */
269 struct workqueue_struct *wq;
270};
271
272int ttm_global_swapout(struct ttm_operation_ctx *ctx, gfp_t gfp_flags);
273int ttm_device_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx,
274 gfp_t gfp_flags);
275int ttm_device_prepare_hibernation(struct ttm_device *bdev);
276
277static inline struct ttm_resource_manager *
278ttm_manager_type(struct ttm_device *bdev, int mem_type)
279{
280 BUILD_BUG_ON(__builtin_constant_p(mem_type)
281 && mem_type >= TTM_NUM_MEM_TYPES);
282 return bdev->man_drv[mem_type];
283}
284
285static inline void ttm_set_driver_manager(struct ttm_device *bdev, int type,
286 struct ttm_resource_manager *manager)
287{
288 BUILD_BUG_ON(__builtin_constant_p(type) && type >= TTM_NUM_MEM_TYPES);
289 bdev->man_drv[type] = manager;
290}
291
292int ttm_device_init(struct ttm_device *bdev, const struct ttm_device_funcs *funcs,
293 struct device *dev, struct address_space *mapping,
294 struct drm_vma_offset_manager *vma_manager,
295 bool use_dma_alloc, bool use_dma32);
296void ttm_device_fini(struct ttm_device *bdev);
297void ttm_device_clear_dma_mappings(struct ttm_device *bdev);
298
299#endif
300