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/list.h>
30 #include <linux/mutex.h>
31 #include <linux/iosys-map.h>
32 #include <linux/dma-fence.h>
33 
34 #include <drm/drm_print.h>
35 #include <drm/ttm/ttm_caching.h>
36 #include <drm/ttm/ttm_kmap_iter.h>
37 
38 #define TTM_MAX_BO_PRIORITY	4U
39 #define TTM_NUM_MEM_TYPES 8
40 
41 struct ttm_device;
42 struct ttm_resource_manager;
43 struct ttm_resource;
44 struct ttm_place;
45 struct ttm_buffer_object;
46 struct ttm_placement;
47 struct iosys_map;
48 struct io_mapping;
49 struct sg_table;
50 struct scatterlist;
51 
52 /**
53  * enum ttm_lru_item_type - enumerate ttm_lru_item subclasses
54  */
55 enum ttm_lru_item_type {
56 	/** @TTM_LRU_RESOURCE: The resource subclass */
57 	TTM_LRU_RESOURCE,
58 	/** @TTM_LRU_HITCH: The iterator hitch subclass */
59 	TTM_LRU_HITCH
60 };
61 
62 /**
63  * struct ttm_lru_item - The TTM lru list node base class
64  * @link: The list link
65  * @type: The subclass type
66  */
67 struct ttm_lru_item {
68 	struct list_head link;
69 	enum ttm_lru_item_type type;
70 };
71 
72 /**
73  * ttm_lru_item_init() - initialize a struct ttm_lru_item
74  * @item: The item to initialize
75  * @type: The subclass type
76  */
ttm_lru_item_init(struct ttm_lru_item * item,enum ttm_lru_item_type type)77 static inline void ttm_lru_item_init(struct ttm_lru_item *item,
78 				     enum ttm_lru_item_type type)
79 {
80 	item->type = type;
81 	INIT_LIST_HEAD(&item->link);
82 }
83 
ttm_lru_item_is_res(const struct ttm_lru_item * item)84 static inline bool ttm_lru_item_is_res(const struct ttm_lru_item *item)
85 {
86 	return item->type == TTM_LRU_RESOURCE;
87 }
88 
89 struct ttm_resource_manager_func {
90 	/**
91 	 * struct ttm_resource_manager_func member alloc
92 	 *
93 	 * @man: Pointer to a memory type manager.
94 	 * @bo: Pointer to the buffer object we're allocating space for.
95 	 * @place: Placement details.
96 	 * @res: Resulting pointer to the ttm_resource.
97 	 *
98 	 * This function should allocate space in the memory type managed
99 	 * by @man. Placement details if applicable are given by @place. If
100 	 * successful, a filled in ttm_resource object should be returned in
101 	 * @res. @res::start should be set to a value identifying the beginning
102 	 * of the range allocated, and the function should return zero.
103 	 * If the manager can't fulfill the request -ENOSPC should be returned.
104 	 * If a system error occurred, preventing the request to be fulfilled,
105 	 * the function should return a negative error code.
106 	 *
107 	 * This function may not be called from within atomic context and needs
108 	 * to take care of its own locking to protect any data structures
109 	 * managing the space.
110 	 */
111 	int  (*alloc)(struct ttm_resource_manager *man,
112 		      struct ttm_buffer_object *bo,
113 		      const struct ttm_place *place,
114 		      struct ttm_resource **res);
115 
116 	/**
117 	 * struct ttm_resource_manager_func member free
118 	 *
119 	 * @man: Pointer to a memory type manager.
120 	 * @res: Pointer to a struct ttm_resource to be freed.
121 	 *
122 	 * This function frees memory type resources previously allocated.
123 	 * May not be called from within atomic context.
124 	 */
125 	void (*free)(struct ttm_resource_manager *man,
126 		     struct ttm_resource *res);
127 
128 	/**
129 	 * struct ttm_resource_manager_func member intersects
130 	 *
131 	 * @man: Pointer to a memory type manager.
132 	 * @res: Pointer to a struct ttm_resource to be checked.
133 	 * @place: Placement to check against.
134 	 * @size: Size of the check.
135 	 *
136 	 * Test if @res intersects with @place + @size. Used to judge if
137 	 * evictions are valueable or not.
138 	 */
139 	bool (*intersects)(struct ttm_resource_manager *man,
140 			   struct ttm_resource *res,
141 			   const struct ttm_place *place,
142 			   size_t size);
143 
144 	/**
145 	 * struct ttm_resource_manager_func member compatible
146 	 *
147 	 * @man: Pointer to a memory type manager.
148 	 * @res: Pointer to a struct ttm_resource to be checked.
149 	 * @place: Placement to check against.
150 	 * @size: Size of the check.
151 	 *
152 	 * Test if @res compatible with @place + @size. Used to check of
153 	 * the need to move the backing store or not.
154 	 */
155 	bool (*compatible)(struct ttm_resource_manager *man,
156 			   struct ttm_resource *res,
157 			   const struct ttm_place *place,
158 			   size_t size);
159 
160 	/**
161 	 * struct ttm_resource_manager_func member debug
162 	 *
163 	 * @man: Pointer to a memory type manager.
164 	 * @printer: Prefix to be used in printout to identify the caller.
165 	 *
166 	 * This function is called to print out the state of the memory
167 	 * type manager to aid debugging of out-of-memory conditions.
168 	 * It may not be called from within atomic context.
169 	 */
170 	void (*debug)(struct ttm_resource_manager *man,
171 		      struct drm_printer *printer);
172 };
173 
174 /**
175  * struct ttm_resource_manager
176  *
177  * @use_type: The memory type is enabled.
178  * @use_tt: If a TT object should be used for the backing store.
179  * @size: Size of the managed region.
180  * @bdev: ttm device this manager belongs to
181  * @func: structure pointer implementing the range manager. See above
182  * @move_lock: lock for move fence
183  * @move: The fence of the last pipelined move operation.
184  * @lru: The lru list for this memory type.
185  *
186  * This structure is used to identify and manage memory types for a device.
187  */
188 struct ttm_resource_manager {
189 	/*
190 	 * No protection. Constant from start.
191 	 */
192 	bool use_type;
193 	bool use_tt;
194 	struct ttm_device *bdev;
195 	uint64_t size;
196 	const struct ttm_resource_manager_func *func;
197 	spinlock_t move_lock;
198 
199 	/*
200 	 * Protected by @move_lock.
201 	 */
202 	struct dma_fence *move;
203 
204 	/*
205 	 * Protected by the bdev->lru_lock.
206 	 */
207 	struct list_head lru[TTM_MAX_BO_PRIORITY];
208 
209 	/**
210 	 * @usage: How much of the resources are used, protected by the
211 	 * bdev->lru_lock.
212 	 */
213 	uint64_t usage;
214 };
215 
216 /**
217  * struct ttm_bus_placement
218  *
219  * @addr:		mapped virtual address
220  * @offset:		physical addr
221  * @is_iomem:		is this io memory ?
222  * @caching:		See enum ttm_caching
223  *
224  * Structure indicating the bus placement of an object.
225  */
226 struct ttm_bus_placement {
227 	void			*addr;
228 	phys_addr_t		offset;
229 	bool			is_iomem;
230 	enum ttm_caching	caching;
231 	bus_space_handle_t	bsh;
232 };
233 
234 /**
235  * struct ttm_resource
236  *
237  * @start: Start of the allocation.
238  * @size: Actual size of resource in bytes.
239  * @mem_type: Resource type of the allocation.
240  * @placement: Placement flags.
241  * @bus: Placement on io bus accessible to the CPU
242  * @bo: weak reference to the BO, protected by ttm_device::lru_lock
243  *
244  * Structure indicating the placement and space resources used by a
245  * buffer object.
246  */
247 struct ttm_resource {
248 	unsigned long start;
249 	size_t size;
250 	uint32_t mem_type;
251 	uint32_t placement;
252 	struct ttm_bus_placement bus;
253 	struct ttm_buffer_object *bo;
254 
255 	/**
256 	 * @lru: Least recently used list, see &ttm_resource_manager.lru
257 	 */
258 	struct ttm_lru_item lru;
259 };
260 
261 /**
262  * ttm_lru_item_to_res() - Downcast a struct ttm_lru_item to a struct ttm_resource
263  * @item: The struct ttm_lru_item to downcast
264  *
265  * Return: Pointer to the embedding struct ttm_resource
266  */
267 static inline struct ttm_resource *
ttm_lru_item_to_res(struct ttm_lru_item * item)268 ttm_lru_item_to_res(struct ttm_lru_item *item)
269 {
270 	return container_of(item, struct ttm_resource, lru);
271 }
272 
273 /**
274  * struct ttm_lru_bulk_move_pos
275  *
276  * @first: first res in the bulk move range
277  * @last: last res in the bulk move range
278  *
279  * Range of resources for a lru bulk move.
280  */
281 struct ttm_lru_bulk_move_pos {
282 	struct ttm_resource *first;
283 	struct ttm_resource *last;
284 };
285 
286 /**
287  * struct ttm_lru_bulk_move
288  * @pos: first/last lru entry for resources in the each domain/priority
289  * @cursor_list: The list of cursors currently traversing any of
290  * the sublists of @pos. Protected by the ttm device's lru_lock.
291  *
292  * Container for the current bulk move state. Should be used with
293  * ttm_lru_bulk_move_init() and ttm_bo_set_bulk_move().
294  * All BOs in a bulk_move structure need to share the same reservation object to
295  * ensure that the bulk as a whole is locked for eviction even if only one BO of
296  * the bulk is evicted.
297  */
298 struct ttm_lru_bulk_move {
299 	struct ttm_lru_bulk_move_pos pos[TTM_NUM_MEM_TYPES][TTM_MAX_BO_PRIORITY];
300 	struct list_head cursor_list;
301 };
302 
303 /**
304  * struct ttm_resource_cursor
305  * @man: The resource manager currently being iterated over
306  * @hitch: A hitch list node inserted before the next resource
307  * to iterate over.
308  * @bulk_link: A list link for the list of cursors traversing the
309  * bulk sublist of @bulk. Protected by the ttm device's lru_lock.
310  * @bulk: Pointer to struct ttm_lru_bulk_move whose subrange @hitch is
311  * inserted to. NULL if none. Never dereference this pointer since
312  * the struct ttm_lru_bulk_move object pointed to might have been
313  * freed. The pointer is only for comparison.
314  * @mem_type: The memory type of the LRU list being traversed.
315  * This field is valid iff @bulk != NULL.
316  * @priority: the current priority
317  *
318  * Cursor to iterate over the resources in a manager.
319  */
320 struct ttm_resource_cursor {
321 	struct ttm_resource_manager *man;
322 	struct ttm_lru_item hitch;
323 	struct list_head bulk_link;
324 	struct ttm_lru_bulk_move *bulk;
325 	unsigned int mem_type;
326 	unsigned int priority;
327 };
328 
329 void ttm_resource_cursor_fini(struct ttm_resource_cursor *cursor);
330 
331 /**
332  * struct ttm_kmap_iter_iomap - Specialization for a struct io_mapping +
333  * struct sg_table backed struct ttm_resource.
334  * @base: Embedded struct ttm_kmap_iter providing the usage interface.
335  * @iomap: struct io_mapping representing the underlying linear io_memory.
336  * @st: sg_table into @iomap, representing the memory of the struct ttm_resource.
337  * @start: Offset that needs to be subtracted from @st to make
338  * sg_dma_address(st->sgl) - @start == 0 for @iomap start.
339  * @cache: Scatterlist traversal cache for fast lookups.
340  * @cache.sg: Pointer to the currently cached scatterlist segment.
341  * @cache.i: First index of @sg. PAGE_SIZE granularity.
342  * @cache.end: Last index + 1 of @sg. PAGE_SIZE granularity.
343  * @cache.offs: First offset into @iomap of @sg. PAGE_SIZE granularity.
344  */
345 struct ttm_kmap_iter_iomap {
346 	struct ttm_kmap_iter base;
347 	struct io_mapping *iomap;
348 	struct sg_table *st;
349 	resource_size_t start;
350 	struct {
351 		struct scatterlist *sg;
352 		pgoff_t i;
353 		pgoff_t end;
354 		pgoff_t offs;
355 	} cache;
356 };
357 
358 /**
359  * struct ttm_kmap_iter_linear_io - Iterator specialization for linear io
360  * @base: The base iterator
361  * @dmap: Points to the starting address of the region
362  * @needs_unmap: Whether we need to unmap on fini
363  */
364 struct ttm_kmap_iter_linear_io {
365 	struct ttm_kmap_iter base;
366 	struct iosys_map dmap;
367 	bool needs_unmap;
368 };
369 
370 /**
371  * ttm_resource_manager_set_used
372  *
373  * @man: A memory manager object.
374  * @used: usage state to set.
375  *
376  * Set the manager in use flag. If disabled the manager is no longer
377  * used for object placement.
378  */
379 static inline void
ttm_resource_manager_set_used(struct ttm_resource_manager * man,bool used)380 ttm_resource_manager_set_used(struct ttm_resource_manager *man, bool used)
381 {
382 	int i;
383 
384 	for (i = 0; i < TTM_MAX_BO_PRIORITY; i++)
385 		WARN_ON(!list_empty(&man->lru[i]));
386 	man->use_type = used;
387 }
388 
389 /**
390  * ttm_resource_manager_used
391  *
392  * @man: Manager to get used state for
393  *
394  * Get the in use flag for a manager.
395  * Returns:
396  * true is used, false if not.
397  */
ttm_resource_manager_used(struct ttm_resource_manager * man)398 static inline bool ttm_resource_manager_used(struct ttm_resource_manager *man)
399 {
400 	return man->use_type;
401 }
402 
403 /**
404  * ttm_resource_manager_cleanup
405  *
406  * @man: A memory manager object.
407  *
408  * Cleanup the move fences from the memory manager object.
409  */
410 static inline void
ttm_resource_manager_cleanup(struct ttm_resource_manager * man)411 ttm_resource_manager_cleanup(struct ttm_resource_manager *man)
412 {
413 	dma_fence_put(man->move);
414 	man->move = NULL;
415 }
416 
417 void ttm_lru_bulk_move_init(struct ttm_lru_bulk_move *bulk);
418 void ttm_lru_bulk_move_tail(struct ttm_lru_bulk_move *bulk);
419 void ttm_lru_bulk_move_fini(struct ttm_device *bdev,
420 			    struct ttm_lru_bulk_move *bulk);
421 
422 void ttm_resource_add_bulk_move(struct ttm_resource *res,
423 				struct ttm_buffer_object *bo);
424 void ttm_resource_del_bulk_move(struct ttm_resource *res,
425 				struct ttm_buffer_object *bo);
426 void ttm_resource_move_to_lru_tail(struct ttm_resource *res);
427 
428 void ttm_resource_init(struct ttm_buffer_object *bo,
429                        const struct ttm_place *place,
430                        struct ttm_resource *res);
431 void ttm_resource_fini(struct ttm_resource_manager *man,
432 		       struct ttm_resource *res);
433 
434 int ttm_resource_alloc(struct ttm_buffer_object *bo,
435 		       const struct ttm_place *place,
436 		       struct ttm_resource **res);
437 void ttm_resource_free(struct ttm_buffer_object *bo, struct ttm_resource **res);
438 bool ttm_resource_intersects(struct ttm_device *bdev,
439 			     struct ttm_resource *res,
440 			     const struct ttm_place *place,
441 			     size_t size);
442 bool ttm_resource_compatible(struct ttm_resource *res,
443 			     struct ttm_placement *placement,
444 			     bool evicting);
445 void ttm_resource_set_bo(struct ttm_resource *res,
446 			 struct ttm_buffer_object *bo);
447 
448 void ttm_resource_manager_init(struct ttm_resource_manager *man,
449 			       struct ttm_device *bdev,
450 			       uint64_t size);
451 
452 int ttm_resource_manager_evict_all(struct ttm_device *bdev,
453 				   struct ttm_resource_manager *man);
454 
455 uint64_t ttm_resource_manager_usage(struct ttm_resource_manager *man);
456 void ttm_resource_manager_debug(struct ttm_resource_manager *man,
457 				struct drm_printer *p);
458 
459 struct ttm_resource *
460 ttm_resource_manager_first(struct ttm_resource_manager *man,
461 			   struct ttm_resource_cursor *cursor);
462 struct ttm_resource *
463 ttm_resource_manager_next(struct ttm_resource_cursor *cursor);
464 
465 struct ttm_resource *
466 ttm_lru_first_res_or_null(struct list_head *head);
467 
468 /**
469  * ttm_resource_manager_for_each_res - iterate over all resources
470  * @man: the resource manager
471  * @cursor: struct ttm_resource_cursor for the current position
472  * @res: the current resource
473  *
474  * Iterate over all the evictable resources in a resource manager.
475  */
476 #define ttm_resource_manager_for_each_res(man, cursor, res)		\
477 	for (res = ttm_resource_manager_first(man, cursor); res;	\
478 	     res = ttm_resource_manager_next(cursor))
479 
480 struct ttm_kmap_iter *
481 ttm_kmap_iter_iomap_init(struct ttm_kmap_iter_iomap *iter_io,
482 			 struct io_mapping *iomap,
483 			 struct sg_table *st,
484 			 resource_size_t start);
485 
486 struct ttm_kmap_iter_linear_io;
487 
488 struct ttm_kmap_iter *
489 ttm_kmap_iter_linear_io_init(struct ttm_kmap_iter_linear_io *iter_io,
490 			     struct ttm_device *bdev,
491 			     struct ttm_resource *mem);
492 
493 void ttm_kmap_iter_linear_io_fini(struct ttm_kmap_iter_linear_io *iter_io,
494 				  struct ttm_device *bdev,
495 				  struct ttm_resource *mem);
496 
497 #ifdef __linux__
498 void ttm_resource_manager_create_debugfs(struct ttm_resource_manager *man,
499 					 struct dentry * parent,
500 					 const char *name);
501 #endif
502 #endif
503