xref: /openbmc/linux/include/drm/ttm/ttm_resource.h (revision 7a2f6f61)
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_RESOURCE_H_
26 #define _TTM_RESOURCE_H_
27 
28 #include <linux/types.h>
29 #include <linux/mutex.h>
30 #include <linux/iosys-map.h>
31 #include <linux/dma-fence.h>
32 #include <drm/drm_print.h>
33 #include <drm/ttm/ttm_caching.h>
34 #include <drm/ttm/ttm_kmap_iter.h>
35 
36 #define TTM_MAX_BO_PRIORITY	4U
37 
38 struct ttm_device;
39 struct ttm_resource_manager;
40 struct ttm_resource;
41 struct ttm_place;
42 struct ttm_buffer_object;
43 struct ttm_placement;
44 struct iosys_map;
45 struct io_mapping;
46 struct sg_table;
47 struct scatterlist;
48 
49 struct ttm_resource_manager_func {
50 	/**
51 	 * struct ttm_resource_manager_func member alloc
52 	 *
53 	 * @man: Pointer to a memory type manager.
54 	 * @bo: Pointer to the buffer object we're allocating space for.
55 	 * @place: Placement details.
56 	 * @res: Resulting pointer to the ttm_resource.
57 	 *
58 	 * This function should allocate space in the memory type managed
59 	 * by @man. Placement details if applicable are given by @place. If
60 	 * successful, a filled in ttm_resource object should be returned in
61 	 * @res. @res::start should be set to a value identifying the beginning
62 	 * of the range allocated, and the function should return zero.
63 	 * If the manager can't fulfill the request -ENOSPC should be returned.
64 	 * If a system error occurred, preventing the request to be fulfilled,
65 	 * the function should return a negative error code.
66 	 *
67 	 * This function may not be called from within atomic context and needs
68 	 * to take care of its own locking to protect any data structures
69 	 * managing the space.
70 	 */
71 	int  (*alloc)(struct ttm_resource_manager *man,
72 		      struct ttm_buffer_object *bo,
73 		      const struct ttm_place *place,
74 		      struct ttm_resource **res);
75 
76 	/**
77 	 * struct ttm_resource_manager_func member free
78 	 *
79 	 * @man: Pointer to a memory type manager.
80 	 * @res: Pointer to a struct ttm_resource to be freed.
81 	 *
82 	 * This function frees memory type resources previously allocated.
83 	 * May not be called from within atomic context.
84 	 */
85 	void (*free)(struct ttm_resource_manager *man,
86 		     struct ttm_resource *res);
87 
88 	/**
89 	 * struct ttm_resource_manager_func member debug
90 	 *
91 	 * @man: Pointer to a memory type manager.
92 	 * @printer: Prefix to be used in printout to identify the caller.
93 	 *
94 	 * This function is called to print out the state of the memory
95 	 * type manager to aid debugging of out-of-memory conditions.
96 	 * It may not be called from within atomic context.
97 	 */
98 	void (*debug)(struct ttm_resource_manager *man,
99 		      struct drm_printer *printer);
100 };
101 
102 /**
103  * struct ttm_resource_manager
104  *
105  * @use_type: The memory type is enabled.
106  * @use_tt: If a TT object should be used for the backing store.
107  * @size: Size of the managed region.
108  * @bdev: ttm device this manager belongs to
109  * @func: structure pointer implementing the range manager. See above
110  * @move_lock: lock for move fence
111  * @move: The fence of the last pipelined move operation.
112  * @lru: The lru list for this memory type.
113  *
114  * This structure is used to identify and manage memory types for a device.
115  */
116 struct ttm_resource_manager {
117 	/*
118 	 * No protection. Constant from start.
119 	 */
120 	bool use_type;
121 	bool use_tt;
122 	struct ttm_device *bdev;
123 	uint64_t size;
124 	const struct ttm_resource_manager_func *func;
125 	spinlock_t move_lock;
126 
127 	/*
128 	 * Protected by @move_lock.
129 	 */
130 	struct dma_fence *move;
131 
132 	/*
133 	 * Protected by the bdev->lru_lock.
134 	 */
135 	struct list_head lru[TTM_MAX_BO_PRIORITY];
136 
137 	/**
138 	 * @usage: How much of the resources are used, protected by the
139 	 * bdev->lru_lock.
140 	 */
141 	uint64_t usage;
142 };
143 
144 /**
145  * struct ttm_bus_placement
146  *
147  * @addr:		mapped virtual address
148  * @offset:		physical addr
149  * @is_iomem:		is this io memory ?
150  * @caching:		See enum ttm_caching
151  *
152  * Structure indicating the bus placement of an object.
153  */
154 struct ttm_bus_placement {
155 	void			*addr;
156 	phys_addr_t		offset;
157 	bool			is_iomem;
158 	enum ttm_caching	caching;
159 };
160 
161 /**
162  * struct ttm_resource
163  *
164  * @start: Start of the allocation.
165  * @num_pages: Actual size of resource in pages.
166  * @mem_type: Resource type of the allocation.
167  * @placement: Placement flags.
168  * @bus: Placement on io bus accessible to the CPU
169  * @bo: weak reference to the BO, protected by ttm_device::lru_lock
170  *
171  * Structure indicating the placement and space resources used by a
172  * buffer object.
173  */
174 struct ttm_resource {
175 	unsigned long start;
176 	unsigned long num_pages;
177 	uint32_t mem_type;
178 	uint32_t placement;
179 	struct ttm_bus_placement bus;
180 	struct ttm_buffer_object *bo;
181 };
182 
183 /**
184  * struct ttm_kmap_iter_iomap - Specialization for a struct io_mapping +
185  * struct sg_table backed struct ttm_resource.
186  * @base: Embedded struct ttm_kmap_iter providing the usage interface.
187  * @iomap: struct io_mapping representing the underlying linear io_memory.
188  * @st: sg_table into @iomap, representing the memory of the struct ttm_resource.
189  * @start: Offset that needs to be subtracted from @st to make
190  * sg_dma_address(st->sgl) - @start == 0 for @iomap start.
191  * @cache: Scatterlist traversal cache for fast lookups.
192  * @cache.sg: Pointer to the currently cached scatterlist segment.
193  * @cache.i: First index of @sg. PAGE_SIZE granularity.
194  * @cache.end: Last index + 1 of @sg. PAGE_SIZE granularity.
195  * @cache.offs: First offset into @iomap of @sg. PAGE_SIZE granularity.
196  */
197 struct ttm_kmap_iter_iomap {
198 	struct ttm_kmap_iter base;
199 	struct io_mapping *iomap;
200 	struct sg_table *st;
201 	resource_size_t start;
202 	struct {
203 		struct scatterlist *sg;
204 		pgoff_t i;
205 		pgoff_t end;
206 		pgoff_t offs;
207 	} cache;
208 };
209 
210 /**
211  * struct ttm_kmap_iter_linear_io - Iterator specialization for linear io
212  * @base: The base iterator
213  * @dmap: Points to the starting address of the region
214  * @needs_unmap: Whether we need to unmap on fini
215  */
216 struct ttm_kmap_iter_linear_io {
217 	struct ttm_kmap_iter base;
218 	struct iosys_map dmap;
219 	bool needs_unmap;
220 };
221 
222 /**
223  * ttm_resource_manager_set_used
224  *
225  * @man: A memory manager object.
226  * @used: usage state to set.
227  *
228  * Set the manager in use flag. If disabled the manager is no longer
229  * used for object placement.
230  */
231 static inline void
232 ttm_resource_manager_set_used(struct ttm_resource_manager *man, bool used)
233 {
234 	int i;
235 
236 	for (i = 0; i < TTM_MAX_BO_PRIORITY; i++)
237 		WARN_ON(!list_empty(&man->lru[i]));
238 	man->use_type = used;
239 }
240 
241 /**
242  * ttm_resource_manager_used
243  *
244  * @man: Manager to get used state for
245  *
246  * Get the in use flag for a manager.
247  * Returns:
248  * true is used, false if not.
249  */
250 static inline bool ttm_resource_manager_used(struct ttm_resource_manager *man)
251 {
252 	return man->use_type;
253 }
254 
255 /**
256  * ttm_resource_manager_cleanup
257  *
258  * @man: A memory manager object.
259  *
260  * Cleanup the move fences from the memory manager object.
261  */
262 static inline void
263 ttm_resource_manager_cleanup(struct ttm_resource_manager *man)
264 {
265 	dma_fence_put(man->move);
266 	man->move = NULL;
267 }
268 
269 void ttm_resource_init(struct ttm_buffer_object *bo,
270                        const struct ttm_place *place,
271                        struct ttm_resource *res);
272 void ttm_resource_fini(struct ttm_resource_manager *man,
273 		       struct ttm_resource *res);
274 
275 int ttm_resource_alloc(struct ttm_buffer_object *bo,
276 		       const struct ttm_place *place,
277 		       struct ttm_resource **res);
278 void ttm_resource_free(struct ttm_buffer_object *bo, struct ttm_resource **res);
279 bool ttm_resource_compat(struct ttm_resource *res,
280 			 struct ttm_placement *placement);
281 void ttm_resource_set_bo(struct ttm_resource *res,
282 			 struct ttm_buffer_object *bo);
283 
284 void ttm_resource_manager_init(struct ttm_resource_manager *man,
285 			       struct ttm_device *bdev,
286 			       uint64_t size);
287 
288 int ttm_resource_manager_evict_all(struct ttm_device *bdev,
289 				   struct ttm_resource_manager *man);
290 
291 uint64_t ttm_resource_manager_usage(struct ttm_resource_manager *man);
292 void ttm_resource_manager_debug(struct ttm_resource_manager *man,
293 				struct drm_printer *p);
294 
295 struct ttm_kmap_iter *
296 ttm_kmap_iter_iomap_init(struct ttm_kmap_iter_iomap *iter_io,
297 			 struct io_mapping *iomap,
298 			 struct sg_table *st,
299 			 resource_size_t start);
300 
301 struct ttm_kmap_iter_linear_io;
302 
303 struct ttm_kmap_iter *
304 ttm_kmap_iter_linear_io_init(struct ttm_kmap_iter_linear_io *iter_io,
305 			     struct ttm_device *bdev,
306 			     struct ttm_resource *mem);
307 
308 void ttm_kmap_iter_linear_io_fini(struct ttm_kmap_iter_linear_io *iter_io,
309 				  struct ttm_device *bdev,
310 				  struct ttm_resource *mem);
311 #endif
312