ttm_device.h

  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_allocation.h>
 31#include <drm/ttm/ttm_resource.h>
 32#include <drm/ttm/ttm_pool.h>
 33
 34struct ttm_device;
 35struct ttm_placement;
 36struct ttm_buffer_object;
 37struct ttm_operation_ctx;
 38
 39/**
 40 * struct ttm_global - Buffer object driver global data.
 41 */
 42extern struct ttm_global {
 43
 44	/**
 45	 * @dummy_read_page: Pointer to a dummy page used for mapping requests
 46	 * of unpopulated pages. Constant after init.
 47	 */
 48	struct page *dummy_read_page;
 49
 50	/**
 51	 * @device_list: List of buffer object devices. Protected by
 52	 * ttm_global_mutex.
 53	 */
 54	struct list_head device_list;
 55
 56	/**
 57	 * @bo_count: Number of buffer objects allocated by devices.
 58	 */
 59	atomic_t bo_count;
 60} ttm_glob;
 61
 62struct ttm_device_funcs {
 63	/**
 64	 * ttm_tt_create
 65	 *
 66	 * @bo: The buffer object to create the ttm for.
 67	 * @page_flags: Page flags as identified by TTM_TT_FLAG_XX flags.
 68	 *
 69	 * Create a struct ttm_tt to back data with system memory pages.
 70	 * No pages are actually allocated.
 71	 * Returns:
 72	 * NULL: Out of memory.
 73	 */
 74	struct ttm_tt *(*ttm_tt_create)(struct ttm_buffer_object *bo,
 75					uint32_t page_flags);
 76
 77	/**
 78	 * ttm_tt_populate
 79	 *
 80	 * @ttm: The struct ttm_tt to contain the backing pages.
 81	 *
 82	 * Allocate all backing pages
 83	 * Returns:
 84	 * -ENOMEM: Out of memory.
 85	 */
 86	int (*ttm_tt_populate)(struct ttm_device *bdev,
 87			       struct ttm_tt *ttm,
 88			       struct ttm_operation_ctx *ctx);
 89
 90	/**
 91	 * ttm_tt_unpopulate
 92	 *
 93	 * @ttm: The struct ttm_tt to contain the backing pages.
 94	 *
 95	 * Free all backing page
 96	 */
 97	void (*ttm_tt_unpopulate)(struct ttm_device *bdev,
 98				  struct ttm_tt *ttm);
 99
100	/**
101	 * ttm_tt_destroy
102	 *
103	 * @bdev: Pointer to a ttm device
104	 * @ttm: Pointer to a struct ttm_tt.
105	 *
106	 * Destroy the backend. This will be call back from ttm_tt_destroy so
107	 * don't call ttm_tt_destroy from the callback or infinite loop.
108	 */
109	void (*ttm_tt_destroy)(struct ttm_device *bdev, struct ttm_tt *ttm);
110
111	/**
112	 * struct ttm_bo_driver member eviction_valuable
113	 *
114	 * @bo: the buffer object to be evicted
115	 * @place: placement we need room for
116	 *
117	 * Check with the driver if it is valuable to evict a BO to make room
118	 * for a certain placement.
119	 */
120	bool (*eviction_valuable)(struct ttm_buffer_object *bo,
121				  const struct ttm_place *place);
122	/**
123	 * struct ttm_bo_driver member evict_flags:
124	 *
125	 * @bo: the buffer object to be evicted
126	 *
127	 * Return the bo flags for a buffer which is not mapped to the hardware.
128	 * These will be placed in proposed_flags so that when the move is
129	 * finished, they'll end up in bo->mem.flags
130	 * This should not cause multihop evictions, and the core will warn
131	 * if one is proposed.
132	 */
133
134	void (*evict_flags)(struct ttm_buffer_object *bo,
135			    struct ttm_placement *placement);
136
137	/**
138	 * struct ttm_bo_driver member move:
139	 *
140	 * @bo: the buffer to move
141	 * @evict: whether this motion is evicting the buffer from
142	 * the graphics address space
143	 * @ctx: context for this move with parameters
144	 * @new_mem: the new memory region receiving the buffer
145	 * @hop: placement for driver directed intermediate hop
146	 *
147	 * Move a buffer between two memory regions.
148	 * Returns errno -EMULTIHOP if driver requests a hop
149	 */
150	int (*move)(struct ttm_buffer_object *bo, bool evict,
151		    struct ttm_operation_ctx *ctx,
152		    struct ttm_resource *new_mem,
153		    struct ttm_place *hop);
154
155	/**
156	 * Hook to notify driver about a resource delete.
157	 */
158	void (*delete_mem_notify)(struct ttm_buffer_object *bo);
159
160	/**
161	 * notify the driver that we're about to swap out this bo
162	 */
163	void (*swap_notify)(struct ttm_buffer_object *bo);
164
165	/**
166	 * Driver callback on when mapping io memory (for bo_move_memcpy
167	 * for instance). TTM will take care to call io_mem_free whenever
168	 * the mapping is not use anymore. io_mem_reserve & io_mem_free
169	 * are balanced.
170	 */
171	int (*io_mem_reserve)(struct ttm_device *bdev,
172			      struct ttm_resource *mem);
173	void (*io_mem_free)(struct ttm_device *bdev,
174			    struct ttm_resource *mem);
175
176	/**
177	 * Return the pfn for a given page_offset inside the BO.
178	 *
179	 * @bo: the BO to look up the pfn for
180	 * @page_offset: the offset to look up
181	 */
182	unsigned long (*io_mem_pfn)(struct ttm_buffer_object *bo,
183				    unsigned long page_offset);
184
185	/**
186	 * Read/write memory buffers for ptrace access
187	 *
188	 * @bo: the BO to access
189	 * @offset: the offset from the start of the BO
190	 * @buf: pointer to source/destination buffer
191	 * @len: number of bytes to copy
192	 * @write: whether to read (0) from or write (non-0) to BO
193	 *
194	 * If successful, this function should return the number of
195	 * bytes copied, -EIO otherwise. If the number of bytes
196	 * returned is < len, the function may be called again with
197	 * the remainder of the buffer to copy.
198	 */
199	int (*access_memory)(struct ttm_buffer_object *bo, unsigned long offset,
200			     void *buf, int len, int write);
201
202	/**
203	 * Notify the driver that we're about to release a BO
204	 *
205	 * @bo: BO that is about to be released
206	 *
207	 * Gives the driver a chance to do any cleanup, including
208	 * adding fences that may force a delayed delete
209	 */
210	void (*release_notify)(struct ttm_buffer_object *bo);
211};
212
213/**
214 * struct ttm_device - Buffer object driver device-specific data.
215 */
216struct ttm_device {
217	/**
218	 * @device_list: Our entry in the global device list.
219	 * Constant after bo device init
220	 */
221	struct list_head device_list;
222
223	/**
224	 * @alloc_flags: TTM_ALLOCATION_* flags.
225	 */
226	unsigned int alloc_flags;
227
228	/**
229	 * @funcs: Function table for the device.
230	 * Constant after bo device init
231	 */
232	const struct ttm_device_funcs *funcs;
233
234	/**
235	 * @sysman: Resource manager for the system domain.
236	 * Access via ttm_manager_type.
237	 */
238	struct ttm_resource_manager sysman;
239
240	/**
241	 * @man_drv: An array of resource_managers, one per resource type.
242	 */
243	struct ttm_resource_manager *man_drv[TTM_NUM_MEM_TYPES];
244
245	/**
246	 * @vma_manager: Address space manager for finding BOs to mmap.
247	 */
248	struct drm_vma_offset_manager *vma_manager;
249
250	/**
251	 * @pool: page pool for the device.
252	 */
253	struct ttm_pool pool;
254
255	/**
256	 * @lru_lock: Protection for the per manager LRU and ddestroy lists.
257	 */
258	spinlock_t lru_lock;
259
260	/**
261	 * @unevictable: Buffer objects which are pinned or swapped and as such
262	 * not on an LRU list.
263	 */
264	struct list_head unevictable;
265
266	/**
267	 * @dev_mapping: A pointer to the struct address_space for invalidating
268	 * CPU mappings on buffer move. Protected by load/unload sync.
269	 */
270	struct address_space *dev_mapping;
271
272	/**
273	 * @wq: Work queue structure for the delayed delete workqueue.
274	 */
275	struct workqueue_struct *wq;
276};
277
278int ttm_global_swapout(struct ttm_operation_ctx *ctx, gfp_t gfp_flags);
279int ttm_device_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx,
280		       gfp_t gfp_flags);
281int ttm_device_prepare_hibernation(struct ttm_device *bdev);
282
283static inline struct ttm_resource_manager *
284ttm_manager_type(struct ttm_device *bdev, int mem_type)
285{
286	BUILD_BUG_ON(__builtin_constant_p(mem_type)
287		     && mem_type >= TTM_NUM_MEM_TYPES);
288	return bdev->man_drv[mem_type];
289}
290
291static inline void ttm_set_driver_manager(struct ttm_device *bdev, int type,
292					  struct ttm_resource_manager *manager)
293{
294	BUILD_BUG_ON(__builtin_constant_p(type) && type >= TTM_NUM_MEM_TYPES);
295	bdev->man_drv[type] = manager;
296}
297
298int ttm_device_init(struct ttm_device *bdev, const struct ttm_device_funcs *funcs,
299		    struct device *dev, struct address_space *mapping,
300		    struct drm_vma_offset_manager *vma_manager,
301		    unsigned int alloc_flags);
302void ttm_device_fini(struct ttm_device *bdev);
303void ttm_device_clear_dma_mappings(struct ttm_device *bdev);
304
305#endif