1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /*
3  * Copyright 2022 Advanced Micro Devices, Inc.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be included in
13  * all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
19  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21  * OTHER DEALINGS IN THE SOFTWARE.
22  */
23 
24 #include <drm/drm_drv.h>
25 
26 #include "amdgpu.h"
27 #include "amdgpu_trace.h"
28 #include "amdgpu_vm.h"
29 
30 /*
31  * amdgpu_vm_pt_cursor - state for for_each_amdgpu_vm_pt
32  */
33 struct amdgpu_vm_pt_cursor {
34 	uint64_t pfn;
35 	struct amdgpu_vm_bo_base *parent;
36 	struct amdgpu_vm_bo_base *entry;
37 	unsigned int level;
38 };
39 
40 /**
41  * amdgpu_vm_pt_level_shift - return the addr shift for each level
42  *
43  * @adev: amdgpu_device pointer
44  * @level: VMPT level
45  *
46  * Returns:
47  * The number of bits the pfn needs to be right shifted for a level.
48  */
49 static unsigned int amdgpu_vm_pt_level_shift(struct amdgpu_device *adev,
50 					     unsigned int level)
51 {
52 	switch (level) {
53 	case AMDGPU_VM_PDB2:
54 	case AMDGPU_VM_PDB1:
55 	case AMDGPU_VM_PDB0:
56 		return 9 * (AMDGPU_VM_PDB0 - level) +
57 			adev->vm_manager.block_size;
58 	case AMDGPU_VM_PTB:
59 		return 0;
60 	default:
61 		return ~0;
62 	}
63 }
64 
65 /**
66  * amdgpu_vm_pt_num_entries - return the number of entries in a PD/PT
67  *
68  * @adev: amdgpu_device pointer
69  * @level: VMPT level
70  *
71  * Returns:
72  * The number of entries in a page directory or page table.
73  */
74 static unsigned int amdgpu_vm_pt_num_entries(struct amdgpu_device *adev,
75 					     unsigned int level)
76 {
77 	unsigned int shift;
78 
79 	shift = amdgpu_vm_pt_level_shift(adev, adev->vm_manager.root_level);
80 	if (level == adev->vm_manager.root_level)
81 		/* For the root directory */
82 		return round_up(adev->vm_manager.max_pfn, 1ULL << shift)
83 			>> shift;
84 	else if (level != AMDGPU_VM_PTB)
85 		/* Everything in between */
86 		return 512;
87 
88 	/* For the page tables on the leaves */
89 	return AMDGPU_VM_PTE_COUNT(adev);
90 }
91 
92 /**
93  * amdgpu_vm_pt_num_ats_entries - return the number of ATS entries in the root PD
94  *
95  * @adev: amdgpu_device pointer
96  *
97  * Returns:
98  * The number of entries in the root page directory which needs the ATS setting.
99  */
100 static unsigned int amdgpu_vm_pt_num_ats_entries(struct amdgpu_device *adev)
101 {
102 	unsigned int shift;
103 
104 	shift = amdgpu_vm_pt_level_shift(adev, adev->vm_manager.root_level);
105 	return AMDGPU_GMC_HOLE_START >> (shift + AMDGPU_GPU_PAGE_SHIFT);
106 }
107 
108 /**
109  * amdgpu_vm_pt_entries_mask - the mask to get the entry number of a PD/PT
110  *
111  * @adev: amdgpu_device pointer
112  * @level: VMPT level
113  *
114  * Returns:
115  * The mask to extract the entry number of a PD/PT from an address.
116  */
117 static uint32_t amdgpu_vm_pt_entries_mask(struct amdgpu_device *adev,
118 					  unsigned int level)
119 {
120 	if (level <= adev->vm_manager.root_level)
121 		return 0xffffffff;
122 	else if (level != AMDGPU_VM_PTB)
123 		return 0x1ff;
124 	else
125 		return AMDGPU_VM_PTE_COUNT(adev) - 1;
126 }
127 
128 /**
129  * amdgpu_vm_pt_size - returns the size of the page table in bytes
130  *
131  * @adev: amdgpu_device pointer
132  * @level: VMPT level
133  *
134  * Returns:
135  * The size of the BO for a page directory or page table in bytes.
136  */
137 static unsigned int amdgpu_vm_pt_size(struct amdgpu_device *adev,
138 				      unsigned int level)
139 {
140 	return AMDGPU_GPU_PAGE_ALIGN(amdgpu_vm_pt_num_entries(adev, level) * 8);
141 }
142 
143 /**
144  * amdgpu_vm_pt_parent - get the parent page directory
145  *
146  * @pt: child page table
147  *
148  * Helper to get the parent entry for the child page table. NULL if we are at
149  * the root page directory.
150  */
151 static struct amdgpu_vm_bo_base *
152 amdgpu_vm_pt_parent(struct amdgpu_vm_bo_base *pt)
153 {
154 	struct amdgpu_bo *parent = pt->bo->parent;
155 
156 	if (!parent)
157 		return NULL;
158 
159 	return parent->vm_bo;
160 }
161 
162 /**
163  * amdgpu_vm_pt_start - start PD/PT walk
164  *
165  * @adev: amdgpu_device pointer
166  * @vm: amdgpu_vm structure
167  * @start: start address of the walk
168  * @cursor: state to initialize
169  *
170  * Initialize a amdgpu_vm_pt_cursor to start a walk.
171  */
172 static void amdgpu_vm_pt_start(struct amdgpu_device *adev,
173 			       struct amdgpu_vm *vm, uint64_t start,
174 			       struct amdgpu_vm_pt_cursor *cursor)
175 {
176 	cursor->pfn = start;
177 	cursor->parent = NULL;
178 	cursor->entry = &vm->root;
179 	cursor->level = adev->vm_manager.root_level;
180 }
181 
182 /**
183  * amdgpu_vm_pt_descendant - go to child node
184  *
185  * @adev: amdgpu_device pointer
186  * @cursor: current state
187  *
188  * Walk to the child node of the current node.
189  * Returns:
190  * True if the walk was possible, false otherwise.
191  */
192 static bool amdgpu_vm_pt_descendant(struct amdgpu_device *adev,
193 				    struct amdgpu_vm_pt_cursor *cursor)
194 {
195 	unsigned int mask, shift, idx;
196 
197 	if ((cursor->level == AMDGPU_VM_PTB) || !cursor->entry ||
198 	    !cursor->entry->bo)
199 		return false;
200 
201 	mask = amdgpu_vm_pt_entries_mask(adev, cursor->level);
202 	shift = amdgpu_vm_pt_level_shift(adev, cursor->level);
203 
204 	++cursor->level;
205 	idx = (cursor->pfn >> shift) & mask;
206 	cursor->parent = cursor->entry;
207 	cursor->entry = &to_amdgpu_bo_vm(cursor->entry->bo)->entries[idx];
208 	return true;
209 }
210 
211 /**
212  * amdgpu_vm_pt_sibling - go to sibling node
213  *
214  * @adev: amdgpu_device pointer
215  * @cursor: current state
216  *
217  * Walk to the sibling node of the current node.
218  * Returns:
219  * True if the walk was possible, false otherwise.
220  */
221 static bool amdgpu_vm_pt_sibling(struct amdgpu_device *adev,
222 				 struct amdgpu_vm_pt_cursor *cursor)
223 {
224 
225 	unsigned int shift, num_entries;
226 	struct amdgpu_bo_vm *parent;
227 
228 	/* Root doesn't have a sibling */
229 	if (!cursor->parent)
230 		return false;
231 
232 	/* Go to our parents and see if we got a sibling */
233 	shift = amdgpu_vm_pt_level_shift(adev, cursor->level - 1);
234 	num_entries = amdgpu_vm_pt_num_entries(adev, cursor->level - 1);
235 	parent = to_amdgpu_bo_vm(cursor->parent->bo);
236 
237 	if (cursor->entry == &parent->entries[num_entries - 1])
238 		return false;
239 
240 	cursor->pfn += 1ULL << shift;
241 	cursor->pfn &= ~((1ULL << shift) - 1);
242 	++cursor->entry;
243 	return true;
244 }
245 
246 /**
247  * amdgpu_vm_pt_ancestor - go to parent node
248  *
249  * @cursor: current state
250  *
251  * Walk to the parent node of the current node.
252  * Returns:
253  * True if the walk was possible, false otherwise.
254  */
255 static bool amdgpu_vm_pt_ancestor(struct amdgpu_vm_pt_cursor *cursor)
256 {
257 	if (!cursor->parent)
258 		return false;
259 
260 	--cursor->level;
261 	cursor->entry = cursor->parent;
262 	cursor->parent = amdgpu_vm_pt_parent(cursor->parent);
263 	return true;
264 }
265 
266 /**
267  * amdgpu_vm_pt_next - get next PD/PT in hieratchy
268  *
269  * @adev: amdgpu_device pointer
270  * @cursor: current state
271  *
272  * Walk the PD/PT tree to the next node.
273  */
274 static void amdgpu_vm_pt_next(struct amdgpu_device *adev,
275 			      struct amdgpu_vm_pt_cursor *cursor)
276 {
277 	/* First try a newborn child */
278 	if (amdgpu_vm_pt_descendant(adev, cursor))
279 		return;
280 
281 	/* If that didn't worked try to find a sibling */
282 	while (!amdgpu_vm_pt_sibling(adev, cursor)) {
283 		/* No sibling, go to our parents and grandparents */
284 		if (!amdgpu_vm_pt_ancestor(cursor)) {
285 			cursor->pfn = ~0ll;
286 			return;
287 		}
288 	}
289 }
290 
291 /**
292  * amdgpu_vm_pt_first_dfs - start a deep first search
293  *
294  * @adev: amdgpu_device structure
295  * @vm: amdgpu_vm structure
296  * @start: optional cursor to start with
297  * @cursor: state to initialize
298  *
299  * Starts a deep first traversal of the PD/PT tree.
300  */
301 static void amdgpu_vm_pt_first_dfs(struct amdgpu_device *adev,
302 				   struct amdgpu_vm *vm,
303 				   struct amdgpu_vm_pt_cursor *start,
304 				   struct amdgpu_vm_pt_cursor *cursor)
305 {
306 	if (start)
307 		*cursor = *start;
308 	else
309 		amdgpu_vm_pt_start(adev, vm, 0, cursor);
310 
311 	while (amdgpu_vm_pt_descendant(adev, cursor))
312 		;
313 }
314 
315 /**
316  * amdgpu_vm_pt_continue_dfs - check if the deep first search should continue
317  *
318  * @start: starting point for the search
319  * @entry: current entry
320  *
321  * Returns:
322  * True when the search should continue, false otherwise.
323  */
324 static bool amdgpu_vm_pt_continue_dfs(struct amdgpu_vm_pt_cursor *start,
325 				      struct amdgpu_vm_bo_base *entry)
326 {
327 	return entry && (!start || entry != start->entry);
328 }
329 
330 /**
331  * amdgpu_vm_pt_next_dfs - get the next node for a deep first search
332  *
333  * @adev: amdgpu_device structure
334  * @cursor: current state
335  *
336  * Move the cursor to the next node in a deep first search.
337  */
338 static void amdgpu_vm_pt_next_dfs(struct amdgpu_device *adev,
339 				  struct amdgpu_vm_pt_cursor *cursor)
340 {
341 	if (!cursor->entry)
342 		return;
343 
344 	if (!cursor->parent)
345 		cursor->entry = NULL;
346 	else if (amdgpu_vm_pt_sibling(adev, cursor))
347 		while (amdgpu_vm_pt_descendant(adev, cursor))
348 			;
349 	else
350 		amdgpu_vm_pt_ancestor(cursor);
351 }
352 
353 /*
354  * for_each_amdgpu_vm_pt_dfs_safe - safe deep first search of all PDs/PTs
355  */
356 #define for_each_amdgpu_vm_pt_dfs_safe(adev, vm, start, cursor, entry)		\
357 	for (amdgpu_vm_pt_first_dfs((adev), (vm), (start), &(cursor)),		\
358 	     (entry) = (cursor).entry, amdgpu_vm_pt_next_dfs((adev), &(cursor));\
359 	     amdgpu_vm_pt_continue_dfs((start), (entry));			\
360 	     (entry) = (cursor).entry, amdgpu_vm_pt_next_dfs((adev), &(cursor)))
361 
362 /**
363  * amdgpu_vm_pt_clear - initially clear the PDs/PTs
364  *
365  * @adev: amdgpu_device pointer
366  * @vm: VM to clear BO from
367  * @vmbo: BO to clear
368  * @immediate: use an immediate update
369  *
370  * Root PD needs to be reserved when calling this.
371  *
372  * Returns:
373  * 0 on success, errno otherwise.
374  */
375 int amdgpu_vm_pt_clear(struct amdgpu_device *adev, struct amdgpu_vm *vm,
376 		       struct amdgpu_bo_vm *vmbo, bool immediate)
377 {
378 	unsigned int level = adev->vm_manager.root_level;
379 	struct ttm_operation_ctx ctx = { true, false };
380 	struct amdgpu_vm_update_params params;
381 	struct amdgpu_bo *ancestor = &vmbo->bo;
382 	unsigned int entries, ats_entries;
383 	struct amdgpu_bo *bo = &vmbo->bo;
384 	uint64_t addr;
385 	int r, idx;
386 
387 	/* Figure out our place in the hierarchy */
388 	if (ancestor->parent) {
389 		++level;
390 		while (ancestor->parent->parent) {
391 			++level;
392 			ancestor = ancestor->parent;
393 		}
394 	}
395 
396 	entries = amdgpu_bo_size(bo) / 8;
397 	if (!vm->pte_support_ats) {
398 		ats_entries = 0;
399 
400 	} else if (!bo->parent) {
401 		ats_entries = amdgpu_vm_pt_num_ats_entries(adev);
402 		ats_entries = min(ats_entries, entries);
403 		entries -= ats_entries;
404 
405 	} else {
406 		struct amdgpu_vm_bo_base *pt;
407 
408 		pt = ancestor->vm_bo;
409 		ats_entries = amdgpu_vm_pt_num_ats_entries(adev);
410 		if ((pt - to_amdgpu_bo_vm(vm->root.bo)->entries) >=
411 		    ats_entries) {
412 			ats_entries = 0;
413 		} else {
414 			ats_entries = entries;
415 			entries = 0;
416 		}
417 	}
418 
419 	r = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
420 	if (r)
421 		return r;
422 
423 	if (vmbo->shadow) {
424 		struct amdgpu_bo *shadow = vmbo->shadow;
425 
426 		r = ttm_bo_validate(&shadow->tbo, &shadow->placement, &ctx);
427 		if (r)
428 			return r;
429 	}
430 
431 	if (!drm_dev_enter(adev_to_drm(adev), &idx))
432 		return -ENODEV;
433 
434 	r = vm->update_funcs->map_table(vmbo);
435 	if (r)
436 		goto exit;
437 
438 	memset(&params, 0, sizeof(params));
439 	params.adev = adev;
440 	params.vm = vm;
441 	params.immediate = immediate;
442 
443 	r = vm->update_funcs->prepare(&params, NULL, AMDGPU_SYNC_EXPLICIT);
444 	if (r)
445 		goto exit;
446 
447 	addr = 0;
448 	if (ats_entries) {
449 		uint64_t value = 0, flags;
450 
451 		flags = AMDGPU_PTE_DEFAULT_ATC;
452 		if (level != AMDGPU_VM_PTB) {
453 			/* Handle leaf PDEs as PTEs */
454 			flags |= AMDGPU_PDE_PTE;
455 			amdgpu_gmc_get_vm_pde(adev, level, &value, &flags);
456 		}
457 
458 		r = vm->update_funcs->update(&params, vmbo, addr, 0,
459 					     ats_entries, value, flags);
460 		if (r)
461 			goto exit;
462 
463 		addr += ats_entries * 8;
464 	}
465 
466 	if (entries) {
467 		uint64_t value = 0, flags = 0;
468 
469 		if (adev->asic_type >= CHIP_VEGA10) {
470 			if (level != AMDGPU_VM_PTB) {
471 				/* Handle leaf PDEs as PTEs */
472 				flags |= AMDGPU_PDE_PTE;
473 				amdgpu_gmc_get_vm_pde(adev, level,
474 						      &value, &flags);
475 			} else {
476 				/* Workaround for fault priority problem on GMC9 */
477 				flags = AMDGPU_PTE_EXECUTABLE;
478 			}
479 		}
480 
481 		r = vm->update_funcs->update(&params, vmbo, addr, 0, entries,
482 					     value, flags);
483 		if (r)
484 			goto exit;
485 	}
486 
487 	r = vm->update_funcs->commit(&params, NULL);
488 exit:
489 	drm_dev_exit(idx);
490 	return r;
491 }
492 
493 /**
494  * amdgpu_vm_pt_create - create bo for PD/PT
495  *
496  * @adev: amdgpu_device pointer
497  * @vm: requesting vm
498  * @level: the page table level
499  * @immediate: use a immediate update
500  * @vmbo: pointer to the buffer object pointer
501  */
502 int amdgpu_vm_pt_create(struct amdgpu_device *adev, struct amdgpu_vm *vm,
503 			int level, bool immediate, struct amdgpu_bo_vm **vmbo)
504 {
505 	struct amdgpu_bo_param bp;
506 	struct amdgpu_bo *bo;
507 	struct dma_resv *resv;
508 	unsigned int num_entries;
509 	int r;
510 
511 	memset(&bp, 0, sizeof(bp));
512 
513 	bp.size = amdgpu_vm_pt_size(adev, level);
514 	bp.byte_align = AMDGPU_GPU_PAGE_SIZE;
515 	bp.domain = AMDGPU_GEM_DOMAIN_VRAM;
516 	bp.domain = amdgpu_bo_get_preferred_domain(adev, bp.domain);
517 	bp.flags = AMDGPU_GEM_CREATE_VRAM_CONTIGUOUS |
518 		AMDGPU_GEM_CREATE_CPU_GTT_USWC;
519 
520 	if (level < AMDGPU_VM_PTB)
521 		num_entries = amdgpu_vm_pt_num_entries(adev, level);
522 	else
523 		num_entries = 0;
524 
525 	bp.bo_ptr_size = struct_size((*vmbo), entries, num_entries);
526 
527 	if (vm->use_cpu_for_update)
528 		bp.flags |= AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED;
529 
530 	bp.type = ttm_bo_type_kernel;
531 	bp.no_wait_gpu = immediate;
532 	if (vm->root.bo)
533 		bp.resv = vm->root.bo->tbo.base.resv;
534 
535 	r = amdgpu_bo_create_vm(adev, &bp, vmbo);
536 	if (r)
537 		return r;
538 
539 	bo = &(*vmbo)->bo;
540 	if (vm->is_compute_context || (adev->flags & AMD_IS_APU)) {
541 		(*vmbo)->shadow = NULL;
542 		return 0;
543 	}
544 
545 	if (!bp.resv)
546 		WARN_ON(dma_resv_lock(bo->tbo.base.resv,
547 				      NULL));
548 	resv = bp.resv;
549 	memset(&bp, 0, sizeof(bp));
550 	bp.size = amdgpu_vm_pt_size(adev, level);
551 	bp.domain = AMDGPU_GEM_DOMAIN_GTT;
552 	bp.flags = AMDGPU_GEM_CREATE_CPU_GTT_USWC;
553 	bp.type = ttm_bo_type_kernel;
554 	bp.resv = bo->tbo.base.resv;
555 	bp.bo_ptr_size = sizeof(struct amdgpu_bo);
556 
557 	r = amdgpu_bo_create(adev, &bp, &(*vmbo)->shadow);
558 
559 	if (!resv)
560 		dma_resv_unlock(bo->tbo.base.resv);
561 
562 	if (r) {
563 		amdgpu_bo_unref(&bo);
564 		return r;
565 	}
566 
567 	(*vmbo)->shadow->parent = amdgpu_bo_ref(bo);
568 	amdgpu_bo_add_to_shadow_list(*vmbo);
569 
570 	return 0;
571 }
572 
573 /**
574  * amdgpu_vm_pt_alloc - Allocate a specific page table
575  *
576  * @adev: amdgpu_device pointer
577  * @vm: VM to allocate page tables for
578  * @cursor: Which page table to allocate
579  * @immediate: use an immediate update
580  *
581  * Make sure a specific page table or directory is allocated.
582  *
583  * Returns:
584  * 1 if page table needed to be allocated, 0 if page table was already
585  * allocated, negative errno if an error occurred.
586  */
587 static int amdgpu_vm_pt_alloc(struct amdgpu_device *adev,
588 			      struct amdgpu_vm *vm,
589 			      struct amdgpu_vm_pt_cursor *cursor,
590 			      bool immediate)
591 {
592 	struct amdgpu_vm_bo_base *entry = cursor->entry;
593 	struct amdgpu_bo *pt_bo;
594 	struct amdgpu_bo_vm *pt;
595 	int r;
596 
597 	if (entry->bo)
598 		return 0;
599 
600 	r = amdgpu_vm_pt_create(adev, vm, cursor->level, immediate, &pt);
601 	if (r)
602 		return r;
603 
604 	/* Keep a reference to the root directory to avoid
605 	 * freeing them up in the wrong order.
606 	 */
607 	pt_bo = &pt->bo;
608 	pt_bo->parent = amdgpu_bo_ref(cursor->parent->bo);
609 	amdgpu_vm_bo_base_init(entry, vm, pt_bo);
610 	r = amdgpu_vm_pt_clear(adev, vm, pt, immediate);
611 	if (r)
612 		goto error_free_pt;
613 
614 	return 0;
615 
616 error_free_pt:
617 	amdgpu_bo_unref(&pt->shadow);
618 	amdgpu_bo_unref(&pt_bo);
619 	return r;
620 }
621 
622 /**
623  * amdgpu_vm_pt_free - free one PD/PT
624  *
625  * @entry: PDE to free
626  */
627 static void amdgpu_vm_pt_free(struct amdgpu_vm_bo_base *entry)
628 {
629 	struct amdgpu_bo *shadow;
630 
631 	if (!entry->bo)
632 		return;
633 	shadow = amdgpu_bo_shadowed(entry->bo);
634 	if (shadow) {
635 		ttm_bo_set_bulk_move(&shadow->tbo, NULL);
636 		amdgpu_bo_unref(&shadow);
637 	}
638 	ttm_bo_set_bulk_move(&entry->bo->tbo, NULL);
639 	entry->bo->vm_bo = NULL;
640 
641 	spin_lock(&entry->vm->status_lock);
642 	list_del(&entry->vm_status);
643 	spin_unlock(&entry->vm->status_lock);
644 	amdgpu_bo_unref(&entry->bo);
645 }
646 
647 void amdgpu_vm_pt_free_work(struct work_struct *work)
648 {
649 	struct amdgpu_vm_bo_base *entry, *next;
650 	struct amdgpu_vm *vm;
651 	LIST_HEAD(pt_freed);
652 
653 	vm = container_of(work, struct amdgpu_vm, pt_free_work);
654 
655 	spin_lock(&vm->status_lock);
656 	list_splice_init(&vm->pt_freed, &pt_freed);
657 	spin_unlock(&vm->status_lock);
658 
659 	/* flush_work in amdgpu_vm_fini ensure vm->root.bo is valid. */
660 	amdgpu_bo_reserve(vm->root.bo, true);
661 
662 	list_for_each_entry_safe(entry, next, &pt_freed, vm_status)
663 		amdgpu_vm_pt_free(entry);
664 
665 	amdgpu_bo_unreserve(vm->root.bo);
666 }
667 
668 /**
669  * amdgpu_vm_pt_free_dfs - free PD/PT levels
670  *
671  * @adev: amdgpu device structure
672  * @vm: amdgpu vm structure
673  * @start: optional cursor where to start freeing PDs/PTs
674  *
675  * Free the page directory or page table level and all sub levels.
676  */
677 static void amdgpu_vm_pt_free_dfs(struct amdgpu_device *adev,
678 				  struct amdgpu_vm *vm,
679 				  struct amdgpu_vm_pt_cursor *start,
680 				  bool unlocked)
681 {
682 	struct amdgpu_vm_pt_cursor cursor;
683 	struct amdgpu_vm_bo_base *entry;
684 
685 	if (unlocked) {
686 		spin_lock(&vm->status_lock);
687 		for_each_amdgpu_vm_pt_dfs_safe(adev, vm, start, cursor, entry)
688 			list_move(&entry->vm_status, &vm->pt_freed);
689 
690 		if (start)
691 			list_move(&start->entry->vm_status, &vm->pt_freed);
692 		spin_unlock(&vm->status_lock);
693 		schedule_work(&vm->pt_free_work);
694 		return;
695 	}
696 
697 	for_each_amdgpu_vm_pt_dfs_safe(adev, vm, start, cursor, entry)
698 		amdgpu_vm_pt_free(entry);
699 
700 	if (start)
701 		amdgpu_vm_pt_free(start->entry);
702 }
703 
704 /**
705  * amdgpu_vm_pt_free_root - free root PD
706  * @adev: amdgpu device structure
707  * @vm: amdgpu vm structure
708  *
709  * Free the root page directory and everything below it.
710  */
711 void amdgpu_vm_pt_free_root(struct amdgpu_device *adev, struct amdgpu_vm *vm)
712 {
713 	amdgpu_vm_pt_free_dfs(adev, vm, NULL, false);
714 }
715 
716 /**
717  * amdgpu_vm_pt_is_root_clean - check if a root PD is clean
718  *
719  * @adev: amdgpu_device pointer
720  * @vm: the VM to check
721  *
722  * Check all entries of the root PD, if any subsequent PDs are allocated,
723  * it means there are page table creating and filling, and is no a clean
724  * VM
725  *
726  * Returns:
727  *	0 if this VM is clean
728  */
729 bool amdgpu_vm_pt_is_root_clean(struct amdgpu_device *adev,
730 				struct amdgpu_vm *vm)
731 {
732 	enum amdgpu_vm_level root = adev->vm_manager.root_level;
733 	unsigned int entries = amdgpu_vm_pt_num_entries(adev, root);
734 	unsigned int i = 0;
735 
736 	for (i = 0; i < entries; i++) {
737 		if (to_amdgpu_bo_vm(vm->root.bo)->entries[i].bo)
738 			return false;
739 	}
740 	return true;
741 }
742 
743 /**
744  * amdgpu_vm_pde_update - update a single level in the hierarchy
745  *
746  * @params: parameters for the update
747  * @entry: entry to update
748  *
749  * Makes sure the requested entry in parent is up to date.
750  */
751 int amdgpu_vm_pde_update(struct amdgpu_vm_update_params *params,
752 			 struct amdgpu_vm_bo_base *entry)
753 {
754 	struct amdgpu_vm_bo_base *parent = amdgpu_vm_pt_parent(entry);
755 	struct amdgpu_bo *bo = parent->bo, *pbo;
756 	struct amdgpu_vm *vm = params->vm;
757 	uint64_t pde, pt, flags;
758 	unsigned int level;
759 
760 	for (level = 0, pbo = bo->parent; pbo; ++level)
761 		pbo = pbo->parent;
762 
763 	level += params->adev->vm_manager.root_level;
764 	amdgpu_gmc_get_pde_for_bo(entry->bo, level, &pt, &flags);
765 	pde = (entry - to_amdgpu_bo_vm(parent->bo)->entries) * 8;
766 	return vm->update_funcs->update(params, to_amdgpu_bo_vm(bo), pde, pt,
767 					1, 0, flags);
768 }
769 
770 /*
771  * amdgpu_vm_pte_update_flags - figure out flags for PTE updates
772  *
773  * Make sure to set the right flags for the PTEs at the desired level.
774  */
775 static void amdgpu_vm_pte_update_flags(struct amdgpu_vm_update_params *params,
776 				       struct amdgpu_bo_vm *pt,
777 				       unsigned int level,
778 				       uint64_t pe, uint64_t addr,
779 				       unsigned int count, uint32_t incr,
780 				       uint64_t flags)
781 
782 {
783 	if (level != AMDGPU_VM_PTB) {
784 		flags |= AMDGPU_PDE_PTE;
785 		amdgpu_gmc_get_vm_pde(params->adev, level, &addr, &flags);
786 
787 	} else if (params->adev->asic_type >= CHIP_VEGA10 &&
788 		   !(flags & AMDGPU_PTE_VALID) &&
789 		   !(flags & AMDGPU_PTE_PRT)) {
790 
791 		/* Workaround for fault priority problem on GMC9 */
792 		flags |= AMDGPU_PTE_EXECUTABLE;
793 	}
794 
795 	params->vm->update_funcs->update(params, pt, pe, addr, count, incr,
796 					 flags);
797 }
798 
799 /**
800  * amdgpu_vm_pte_fragment - get fragment for PTEs
801  *
802  * @params: see amdgpu_vm_update_params definition
803  * @start: first PTE to handle
804  * @end: last PTE to handle
805  * @flags: hw mapping flags
806  * @frag: resulting fragment size
807  * @frag_end: end of this fragment
808  *
809  * Returns the first possible fragment for the start and end address.
810  */
811 static void amdgpu_vm_pte_fragment(struct amdgpu_vm_update_params *params,
812 				   uint64_t start, uint64_t end, uint64_t flags,
813 				   unsigned int *frag, uint64_t *frag_end)
814 {
815 	/**
816 	 * The MC L1 TLB supports variable sized pages, based on a fragment
817 	 * field in the PTE. When this field is set to a non-zero value, page
818 	 * granularity is increased from 4KB to (1 << (12 + frag)). The PTE
819 	 * flags are considered valid for all PTEs within the fragment range
820 	 * and corresponding mappings are assumed to be physically contiguous.
821 	 *
822 	 * The L1 TLB can store a single PTE for the whole fragment,
823 	 * significantly increasing the space available for translation
824 	 * caching. This leads to large improvements in throughput when the
825 	 * TLB is under pressure.
826 	 *
827 	 * The L2 TLB distributes small and large fragments into two
828 	 * asymmetric partitions. The large fragment cache is significantly
829 	 * larger. Thus, we try to use large fragments wherever possible.
830 	 * Userspace can support this by aligning virtual base address and
831 	 * allocation size to the fragment size.
832 	 *
833 	 * Starting with Vega10 the fragment size only controls the L1. The L2
834 	 * is now directly feed with small/huge/giant pages from the walker.
835 	 */
836 	unsigned int max_frag;
837 
838 	if (params->adev->asic_type < CHIP_VEGA10)
839 		max_frag = params->adev->vm_manager.fragment_size;
840 	else
841 		max_frag = 31;
842 
843 	/* system pages are non continuously */
844 	if (params->pages_addr) {
845 		*frag = 0;
846 		*frag_end = end;
847 		return;
848 	}
849 
850 	/* This intentionally wraps around if no bit is set */
851 	*frag = min_t(unsigned int, ffs(start) - 1, fls64(end - start) - 1);
852 	if (*frag >= max_frag) {
853 		*frag = max_frag;
854 		*frag_end = end & ~((1ULL << max_frag) - 1);
855 	} else {
856 		*frag_end = start + (1 << *frag);
857 	}
858 }
859 
860 /**
861  * amdgpu_vm_ptes_update - make sure that page tables are valid
862  *
863  * @params: see amdgpu_vm_update_params definition
864  * @start: start of GPU address range
865  * @end: end of GPU address range
866  * @dst: destination address to map to, the next dst inside the function
867  * @flags: mapping flags
868  *
869  * Update the page tables in the range @start - @end.
870  *
871  * Returns:
872  * 0 for success, -EINVAL for failure.
873  */
874 int amdgpu_vm_ptes_update(struct amdgpu_vm_update_params *params,
875 			  uint64_t start, uint64_t end,
876 			  uint64_t dst, uint64_t flags)
877 {
878 	struct amdgpu_device *adev = params->adev;
879 	struct amdgpu_vm_pt_cursor cursor;
880 	uint64_t frag_start = start, frag_end;
881 	unsigned int frag;
882 	int r;
883 
884 	/* figure out the initial fragment */
885 	amdgpu_vm_pte_fragment(params, frag_start, end, flags, &frag,
886 			       &frag_end);
887 
888 	/* walk over the address space and update the PTs */
889 	amdgpu_vm_pt_start(adev, params->vm, start, &cursor);
890 	while (cursor.pfn < end) {
891 		unsigned int shift, parent_shift, mask;
892 		uint64_t incr, entry_end, pe_start;
893 		struct amdgpu_bo *pt;
894 
895 		if (!params->unlocked) {
896 			/* make sure that the page tables covering the
897 			 * address range are actually allocated
898 			 */
899 			r = amdgpu_vm_pt_alloc(params->adev, params->vm,
900 					       &cursor, params->immediate);
901 			if (r)
902 				return r;
903 		}
904 
905 		shift = amdgpu_vm_pt_level_shift(adev, cursor.level);
906 		parent_shift = amdgpu_vm_pt_level_shift(adev, cursor.level - 1);
907 		if (params->unlocked) {
908 			/* Unlocked updates are only allowed on the leaves */
909 			if (amdgpu_vm_pt_descendant(adev, &cursor))
910 				continue;
911 		} else if (adev->asic_type < CHIP_VEGA10 &&
912 			   (flags & AMDGPU_PTE_VALID)) {
913 			/* No huge page support before GMC v9 */
914 			if (cursor.level != AMDGPU_VM_PTB) {
915 				if (!amdgpu_vm_pt_descendant(adev, &cursor))
916 					return -ENOENT;
917 				continue;
918 			}
919 		} else if (frag < shift) {
920 			/* We can't use this level when the fragment size is
921 			 * smaller than the address shift. Go to the next
922 			 * child entry and try again.
923 			 */
924 			if (amdgpu_vm_pt_descendant(adev, &cursor))
925 				continue;
926 		} else if (frag >= parent_shift) {
927 			/* If the fragment size is even larger than the parent
928 			 * shift we should go up one level and check it again.
929 			 */
930 			if (!amdgpu_vm_pt_ancestor(&cursor))
931 				return -EINVAL;
932 			continue;
933 		}
934 
935 		pt = cursor.entry->bo;
936 		if (!pt) {
937 			/* We need all PDs and PTs for mapping something, */
938 			if (flags & AMDGPU_PTE_VALID)
939 				return -ENOENT;
940 
941 			/* but unmapping something can happen at a higher
942 			 * level.
943 			 */
944 			if (!amdgpu_vm_pt_ancestor(&cursor))
945 				return -EINVAL;
946 
947 			pt = cursor.entry->bo;
948 			shift = parent_shift;
949 			frag_end = max(frag_end, ALIGN(frag_start + 1,
950 				   1ULL << shift));
951 		}
952 
953 		/* Looks good so far, calculate parameters for the update */
954 		incr = (uint64_t)AMDGPU_GPU_PAGE_SIZE << shift;
955 		mask = amdgpu_vm_pt_entries_mask(adev, cursor.level);
956 		pe_start = ((cursor.pfn >> shift) & mask) * 8;
957 		entry_end = ((uint64_t)mask + 1) << shift;
958 		entry_end += cursor.pfn & ~(entry_end - 1);
959 		entry_end = min(entry_end, end);
960 
961 		do {
962 			struct amdgpu_vm *vm = params->vm;
963 			uint64_t upd_end = min(entry_end, frag_end);
964 			unsigned int nptes = (upd_end - frag_start) >> shift;
965 			uint64_t upd_flags = flags | AMDGPU_PTE_FRAG(frag);
966 
967 			/* This can happen when we set higher level PDs to
968 			 * silent to stop fault floods.
969 			 */
970 			nptes = max(nptes, 1u);
971 
972 			trace_amdgpu_vm_update_ptes(params, frag_start, upd_end,
973 						    min(nptes, 32u), dst, incr,
974 						    upd_flags,
975 						    vm->task_info.pid,
976 						    vm->immediate.fence_context);
977 			amdgpu_vm_pte_update_flags(params, to_amdgpu_bo_vm(pt),
978 						   cursor.level, pe_start, dst,
979 						   nptes, incr, upd_flags);
980 
981 			pe_start += nptes * 8;
982 			dst += nptes * incr;
983 
984 			frag_start = upd_end;
985 			if (frag_start >= frag_end) {
986 				/* figure out the next fragment */
987 				amdgpu_vm_pte_fragment(params, frag_start, end,
988 						       flags, &frag, &frag_end);
989 				if (frag < shift)
990 					break;
991 			}
992 		} while (frag_start < entry_end);
993 
994 		if (amdgpu_vm_pt_descendant(adev, &cursor)) {
995 			/* Free all child entries.
996 			 * Update the tables with the flags and addresses and free up subsequent
997 			 * tables in the case of huge pages or freed up areas.
998 			 * This is the maximum you can free, because all other page tables are not
999 			 * completely covered by the range and so potentially still in use.
1000 			 */
1001 			while (cursor.pfn < frag_start) {
1002 				/* Make sure previous mapping is freed */
1003 				if (cursor.entry->bo) {
1004 					params->table_freed = true;
1005 					amdgpu_vm_pt_free_dfs(adev, params->vm,
1006 							      &cursor,
1007 							      params->unlocked);
1008 				}
1009 				amdgpu_vm_pt_next(adev, &cursor);
1010 			}
1011 
1012 		} else if (frag >= shift) {
1013 			/* or just move on to the next on the same level. */
1014 			amdgpu_vm_pt_next(adev, &cursor);
1015 		}
1016 	}
1017 
1018 	return 0;
1019 }
1020