xref: /linux/drivers/gpu/drm/xe/xe_ttm_vram_mgr.c (revision 44343e8b250abb2f6bfd615493ca07a7f11f3cc2)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2021-2022 Intel Corporation
4  * Copyright (C) 2021-2002 Red Hat
5  */
6 
7 #include <drm/drm_managed.h>
8 #include <drm/drm_drv.h>
9 
10 #include <drm/ttm/ttm_placement.h>
11 #include <drm/ttm/ttm_range_manager.h>
12 
13 #include "xe_bo.h"
14 #include "xe_device.h"
15 #include "xe_gt.h"
16 #include "xe_res_cursor.h"
17 #include "xe_ttm_vram_mgr.h"
18 #include "xe_vram_types.h"
19 
20 static inline struct drm_buddy_block *
21 xe_ttm_vram_mgr_first_block(struct list_head *list)
22 {
23 	return list_first_entry_or_null(list, struct drm_buddy_block, link);
24 }
25 
26 static inline bool xe_is_vram_mgr_blocks_contiguous(struct drm_buddy *mm,
27 						    struct list_head *head)
28 {
29 	struct drm_buddy_block *block;
30 	u64 start, size;
31 
32 	block = xe_ttm_vram_mgr_first_block(head);
33 	if (!block)
34 		return false;
35 
36 	while (head != block->link.next) {
37 		start = drm_buddy_block_offset(block);
38 		size = drm_buddy_block_size(mm, block);
39 
40 		block = list_entry(block->link.next, struct drm_buddy_block,
41 				   link);
42 		if (start + size != drm_buddy_block_offset(block))
43 			return false;
44 	}
45 
46 	return true;
47 }
48 
49 static int xe_ttm_vram_mgr_new(struct ttm_resource_manager *man,
50 			       struct ttm_buffer_object *tbo,
51 			       const struct ttm_place *place,
52 			       struct ttm_resource **res)
53 {
54 	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
55 	struct xe_ttm_vram_mgr_resource *vres;
56 	struct drm_buddy *mm = &mgr->mm;
57 	u64 size, min_page_size;
58 	unsigned long lpfn;
59 	int err;
60 
61 	lpfn = place->lpfn;
62 	if (!lpfn || lpfn > man->size >> PAGE_SHIFT)
63 		lpfn = man->size >> PAGE_SHIFT;
64 
65 	if (tbo->base.size >> PAGE_SHIFT > (lpfn - place->fpfn))
66 		return -E2BIG; /* don't trigger eviction for the impossible */
67 
68 	vres = kzalloc(sizeof(*vres), GFP_KERNEL);
69 	if (!vres)
70 		return -ENOMEM;
71 
72 	ttm_resource_init(tbo, place, &vres->base);
73 
74 	/* bail out quickly if there's likely not enough VRAM for this BO */
75 	if (ttm_resource_manager_usage(man) > man->size) {
76 		err = -ENOSPC;
77 		goto error_fini;
78 	}
79 
80 	INIT_LIST_HEAD(&vres->blocks);
81 
82 	if (place->flags & TTM_PL_FLAG_TOPDOWN)
83 		vres->flags |= DRM_BUDDY_TOPDOWN_ALLOCATION;
84 
85 	if (place->fpfn || lpfn != man->size >> PAGE_SHIFT)
86 		vres->flags |= DRM_BUDDY_RANGE_ALLOCATION;
87 
88 	if (WARN_ON(!vres->base.size)) {
89 		err = -EINVAL;
90 		goto error_fini;
91 	}
92 	size = vres->base.size;
93 
94 	min_page_size = mgr->default_page_size;
95 	if (tbo->page_alignment)
96 		min_page_size = (u64)tbo->page_alignment << PAGE_SHIFT;
97 
98 	if (WARN_ON(min_page_size < mm->chunk_size)) {
99 		err = -EINVAL;
100 		goto error_fini;
101 	}
102 
103 	if (WARN_ON(!IS_ALIGNED(size, min_page_size))) {
104 		err = -EINVAL;
105 		goto error_fini;
106 	}
107 
108 	mutex_lock(&mgr->lock);
109 	if (lpfn <= mgr->visible_size >> PAGE_SHIFT && size > mgr->visible_avail) {
110 		err = -ENOSPC;
111 		goto error_unlock;
112 	}
113 
114 	if (place->fpfn + (size >> PAGE_SHIFT) != lpfn &&
115 	    place->flags & TTM_PL_FLAG_CONTIGUOUS) {
116 		size = roundup_pow_of_two(size);
117 		min_page_size = size;
118 
119 		lpfn = max_t(unsigned long, place->fpfn + (size >> PAGE_SHIFT), lpfn);
120 	}
121 
122 	err = drm_buddy_alloc_blocks(mm, (u64)place->fpfn << PAGE_SHIFT,
123 				     (u64)lpfn << PAGE_SHIFT, size,
124 				     min_page_size, &vres->blocks, vres->flags);
125 	if (err)
126 		goto error_unlock;
127 
128 	if (place->flags & TTM_PL_FLAG_CONTIGUOUS) {
129 		if (!drm_buddy_block_trim(mm, NULL, vres->base.size, &vres->blocks))
130 			size = vres->base.size;
131 	}
132 
133 	if (lpfn <= mgr->visible_size >> PAGE_SHIFT) {
134 		vres->used_visible_size = size;
135 	} else {
136 		struct drm_buddy_block *block;
137 
138 		list_for_each_entry(block, &vres->blocks, link) {
139 			u64 start = drm_buddy_block_offset(block);
140 
141 			if (start < mgr->visible_size) {
142 				u64 end = start + drm_buddy_block_size(mm, block);
143 
144 				vres->used_visible_size +=
145 					min(end, mgr->visible_size) - start;
146 			}
147 		}
148 	}
149 
150 	mgr->visible_avail -= vres->used_visible_size;
151 	mutex_unlock(&mgr->lock);
152 
153 	if (!(vres->base.placement & TTM_PL_FLAG_CONTIGUOUS) &&
154 	    xe_is_vram_mgr_blocks_contiguous(mm, &vres->blocks))
155 		vres->base.placement |= TTM_PL_FLAG_CONTIGUOUS;
156 
157 	/*
158 	 * For some kernel objects we still rely on the start when io mapping
159 	 * the object.
160 	 */
161 	if (vres->base.placement & TTM_PL_FLAG_CONTIGUOUS) {
162 		struct drm_buddy_block *block = list_first_entry(&vres->blocks,
163 								 typeof(*block),
164 								 link);
165 
166 		vres->base.start = drm_buddy_block_offset(block) >> PAGE_SHIFT;
167 	} else {
168 		vres->base.start = XE_BO_INVALID_OFFSET;
169 	}
170 
171 	*res = &vres->base;
172 	return 0;
173 error_unlock:
174 	mutex_unlock(&mgr->lock);
175 error_fini:
176 	ttm_resource_fini(man, &vres->base);
177 	kfree(vres);
178 
179 	return err;
180 }
181 
182 static void xe_ttm_vram_mgr_del(struct ttm_resource_manager *man,
183 				struct ttm_resource *res)
184 {
185 	struct xe_ttm_vram_mgr_resource *vres =
186 		to_xe_ttm_vram_mgr_resource(res);
187 	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
188 	struct drm_buddy *mm = &mgr->mm;
189 
190 	mutex_lock(&mgr->lock);
191 	drm_buddy_free_list(mm, &vres->blocks, 0);
192 	mgr->visible_avail += vres->used_visible_size;
193 	mutex_unlock(&mgr->lock);
194 
195 	ttm_resource_fini(man, res);
196 
197 	kfree(vres);
198 }
199 
200 static void xe_ttm_vram_mgr_debug(struct ttm_resource_manager *man,
201 				  struct drm_printer *printer)
202 {
203 	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
204 	struct drm_buddy *mm = &mgr->mm;
205 
206 	mutex_lock(&mgr->lock);
207 	drm_printf(printer, "default_page_size: %lluKiB\n",
208 		   mgr->default_page_size >> 10);
209 	drm_printf(printer, "visible_avail: %lluMiB\n",
210 		   (u64)mgr->visible_avail >> 20);
211 	drm_printf(printer, "visible_size: %lluMiB\n",
212 		   (u64)mgr->visible_size >> 20);
213 
214 	drm_buddy_print(mm, printer);
215 	mutex_unlock(&mgr->lock);
216 	drm_printf(printer, "man size:%llu\n", man->size);
217 }
218 
219 static bool xe_ttm_vram_mgr_intersects(struct ttm_resource_manager *man,
220 				       struct ttm_resource *res,
221 				       const struct ttm_place *place,
222 				       size_t size)
223 {
224 	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
225 	struct xe_ttm_vram_mgr_resource *vres =
226 		to_xe_ttm_vram_mgr_resource(res);
227 	struct drm_buddy *mm = &mgr->mm;
228 	struct drm_buddy_block *block;
229 
230 	if (!place->fpfn && !place->lpfn)
231 		return true;
232 
233 	if (!place->fpfn && place->lpfn == mgr->visible_size >> PAGE_SHIFT)
234 		return vres->used_visible_size > 0;
235 
236 	list_for_each_entry(block, &vres->blocks, link) {
237 		unsigned long fpfn =
238 			drm_buddy_block_offset(block) >> PAGE_SHIFT;
239 		unsigned long lpfn = fpfn +
240 			(drm_buddy_block_size(mm, block) >> PAGE_SHIFT);
241 
242 		if (place->fpfn < lpfn && place->lpfn > fpfn)
243 			return true;
244 	}
245 
246 	return false;
247 }
248 
249 static bool xe_ttm_vram_mgr_compatible(struct ttm_resource_manager *man,
250 				       struct ttm_resource *res,
251 				       const struct ttm_place *place,
252 				       size_t size)
253 {
254 	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
255 	struct xe_ttm_vram_mgr_resource *vres =
256 		to_xe_ttm_vram_mgr_resource(res);
257 	struct drm_buddy *mm = &mgr->mm;
258 	struct drm_buddy_block *block;
259 
260 	if (!place->fpfn && !place->lpfn)
261 		return true;
262 
263 	if (!place->fpfn && place->lpfn == mgr->visible_size >> PAGE_SHIFT)
264 		return vres->used_visible_size == size;
265 
266 	list_for_each_entry(block, &vres->blocks, link) {
267 		unsigned long fpfn =
268 			drm_buddy_block_offset(block) >> PAGE_SHIFT;
269 		unsigned long lpfn = fpfn +
270 			(drm_buddy_block_size(mm, block) >> PAGE_SHIFT);
271 
272 		if (fpfn < place->fpfn || lpfn > place->lpfn)
273 			return false;
274 	}
275 
276 	return true;
277 }
278 
279 static const struct ttm_resource_manager_func xe_ttm_vram_mgr_func = {
280 	.alloc	= xe_ttm_vram_mgr_new,
281 	.free	= xe_ttm_vram_mgr_del,
282 	.intersects = xe_ttm_vram_mgr_intersects,
283 	.compatible = xe_ttm_vram_mgr_compatible,
284 	.debug	= xe_ttm_vram_mgr_debug
285 };
286 
287 static void ttm_vram_mgr_fini(struct drm_device *dev, void *arg)
288 {
289 	struct xe_device *xe = to_xe_device(dev);
290 	struct xe_ttm_vram_mgr *mgr = arg;
291 	struct ttm_resource_manager *man = &mgr->manager;
292 
293 	ttm_resource_manager_set_used(man, false);
294 
295 	if (ttm_resource_manager_evict_all(&xe->ttm, man))
296 		return;
297 
298 	WARN_ON_ONCE(mgr->visible_avail != mgr->visible_size);
299 
300 	drm_buddy_fini(&mgr->mm);
301 
302 	ttm_resource_manager_cleanup(&mgr->manager);
303 
304 	ttm_set_driver_manager(&xe->ttm, mgr->mem_type, NULL);
305 
306 	mutex_destroy(&mgr->lock);
307 }
308 
309 int __xe_ttm_vram_mgr_init(struct xe_device *xe, struct xe_ttm_vram_mgr *mgr,
310 			   u32 mem_type, u64 size, u64 io_size,
311 			   u64 default_page_size)
312 {
313 	struct ttm_resource_manager *man = &mgr->manager;
314 	int err;
315 
316 	if (mem_type != XE_PL_STOLEN) {
317 		const char *name = mem_type == XE_PL_VRAM0 ? "vram0" : "vram1";
318 		man->cg = drmm_cgroup_register_region(&xe->drm, name, size);
319 		if (IS_ERR(man->cg))
320 			return PTR_ERR(man->cg);
321 	}
322 
323 	man->func = &xe_ttm_vram_mgr_func;
324 	mgr->mem_type = mem_type;
325 	mutex_init(&mgr->lock);
326 	mgr->default_page_size = default_page_size;
327 	mgr->visible_size = io_size;
328 	mgr->visible_avail = io_size;
329 
330 	ttm_resource_manager_init(man, &xe->ttm, size);
331 	err = drm_buddy_init(&mgr->mm, man->size, default_page_size);
332 	if (err)
333 		return err;
334 
335 	ttm_set_driver_manager(&xe->ttm, mem_type, &mgr->manager);
336 	ttm_resource_manager_set_used(&mgr->manager, true);
337 
338 	return drmm_add_action_or_reset(&xe->drm, ttm_vram_mgr_fini, mgr);
339 }
340 
341 /**
342  * xe_ttm_vram_mgr_init - initialize TTM VRAM region
343  * @xe: pointer to Xe device
344  * @vram: pointer to xe_vram_region that contains the memory region attributes
345  *
346  * Initialize the Xe TTM for given @vram region using the given parameters.
347  *
348  * Returns 0 for success, negative error code otherwise.
349  */
350 int xe_ttm_vram_mgr_init(struct xe_device *xe, struct xe_vram_region *vram)
351 {
352 	return __xe_ttm_vram_mgr_init(xe, &vram->ttm, vram->placement,
353 				      xe_vram_region_usable_size(vram),
354 				      xe_vram_region_io_size(vram),
355 				      PAGE_SIZE);
356 }
357 
358 int xe_ttm_vram_mgr_alloc_sgt(struct xe_device *xe,
359 			      struct ttm_resource *res,
360 			      u64 offset, u64 length,
361 			      struct device *dev,
362 			      enum dma_data_direction dir,
363 			      struct sg_table **sgt)
364 {
365 	struct xe_tile *tile = &xe->tiles[res->mem_type - XE_PL_VRAM0];
366 	struct xe_ttm_vram_mgr_resource *vres = to_xe_ttm_vram_mgr_resource(res);
367 	struct xe_res_cursor cursor;
368 	struct scatterlist *sg;
369 	int num_entries = 0;
370 	int i, r;
371 
372 	if (vres->used_visible_size < res->size)
373 		return -EOPNOTSUPP;
374 
375 	*sgt = kmalloc(sizeof(**sgt), GFP_KERNEL);
376 	if (!*sgt)
377 		return -ENOMEM;
378 
379 	/* Determine the number of DRM_BUDDY blocks to export */
380 	xe_res_first(res, offset, length, &cursor);
381 	while (cursor.remaining) {
382 		num_entries++;
383 		/* Limit maximum size to 2GiB due to SG table limitations. */
384 		xe_res_next(&cursor, min_t(u64, cursor.size, SZ_2G));
385 	}
386 
387 	r = sg_alloc_table(*sgt, num_entries, GFP_KERNEL);
388 	if (r)
389 		goto error_free;
390 
391 	/* Initialize scatterlist nodes of sg_table */
392 	for_each_sgtable_sg((*sgt), sg, i)
393 		sg->length = 0;
394 
395 	/*
396 	 * Walk down DRM_BUDDY blocks to populate scatterlist nodes
397 	 * @note: Use iterator api to get first the DRM_BUDDY block
398 	 * and the number of bytes from it. Access the following
399 	 * DRM_BUDDY block(s) if more buffer needs to exported
400 	 */
401 	xe_res_first(res, offset, length, &cursor);
402 	for_each_sgtable_sg((*sgt), sg, i) {
403 		phys_addr_t phys = cursor.start + xe_vram_region_io_start(tile->mem.vram);
404 		size_t size = min_t(u64, cursor.size, SZ_2G);
405 		dma_addr_t addr;
406 
407 		addr = dma_map_resource(dev, phys, size, dir,
408 					DMA_ATTR_SKIP_CPU_SYNC);
409 		r = dma_mapping_error(dev, addr);
410 		if (r)
411 			goto error_unmap;
412 
413 		sg_set_page(sg, NULL, size, 0);
414 		sg_dma_address(sg) = addr;
415 		sg_dma_len(sg) = size;
416 
417 		xe_res_next(&cursor, size);
418 	}
419 
420 	return 0;
421 
422 error_unmap:
423 	for_each_sgtable_sg((*sgt), sg, i) {
424 		if (!sg->length)
425 			continue;
426 
427 		dma_unmap_resource(dev, sg->dma_address,
428 				   sg->length, dir,
429 				   DMA_ATTR_SKIP_CPU_SYNC);
430 	}
431 	sg_free_table(*sgt);
432 
433 error_free:
434 	kfree(*sgt);
435 	return r;
436 }
437 
438 void xe_ttm_vram_mgr_free_sgt(struct device *dev, enum dma_data_direction dir,
439 			      struct sg_table *sgt)
440 {
441 	struct scatterlist *sg;
442 	int i;
443 
444 	for_each_sgtable_sg(sgt, sg, i)
445 		dma_unmap_resource(dev, sg->dma_address,
446 				   sg->length, dir,
447 				   DMA_ATTR_SKIP_CPU_SYNC);
448 	sg_free_table(sgt);
449 	kfree(sgt);
450 }
451 
452 u64 xe_ttm_vram_get_cpu_visible_size(struct ttm_resource_manager *man)
453 {
454 	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
455 
456 	return mgr->visible_size;
457 }
458 
459 void xe_ttm_vram_get_used(struct ttm_resource_manager *man,
460 			  u64 *used, u64 *used_visible)
461 {
462 	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
463 
464 	mutex_lock(&mgr->lock);
465 	*used = mgr->mm.size - mgr->mm.avail;
466 	*used_visible = mgr->visible_size - mgr->visible_avail;
467 	mutex_unlock(&mgr->lock);
468 }
469 
470 u64 xe_ttm_vram_get_avail(struct ttm_resource_manager *man)
471 {
472 	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
473 	u64 avail;
474 
475 	mutex_lock(&mgr->lock);
476 	avail =  mgr->mm.avail;
477 	mutex_unlock(&mgr->lock);
478 
479 	return avail;
480 }
481