xref: /linux/drivers/accel/habanalabs/common/mmu/mmu.c (revision 4b911a9690d72641879ea6d13cce1de31d346d79)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 /*
4  * Copyright 2016-2022 HabanaLabs, Ltd.
5  * All Rights Reserved.
6  */
7 
8 #include <linux/slab.h>
9 
10 #include "../habanalabs.h"
11 
12 #include <trace/events/habanalabs.h>
13 
14 /**
15  * hl_mmu_get_funcs() - get MMU functions structure
16  * @hdev: habanalabs device structure.
17  * @pgt_residency: page table residency.
18  * @is_dram_addr: true if we need HMMU functions
19  *
20  * @return appropriate MMU functions structure
21  */
22 static struct hl_mmu_funcs *hl_mmu_get_funcs(struct hl_device *hdev, int pgt_residency,
23 									bool is_dram_addr)
24 {
25 	return &hdev->mmu_func[pgt_residency];
26 }
27 
28 bool hl_is_dram_va(struct hl_device *hdev, u64 virt_addr)
29 {
30 	struct asic_fixed_properties *prop = &hdev->asic_prop;
31 
32 	return hl_mem_area_inside_range(virt_addr, prop->dmmu.page_size,
33 					prop->dmmu.start_addr,
34 					prop->dmmu.end_addr);
35 }
36 
37 /**
38  * hl_mmu_init() - initialize the MMU module.
39  * @hdev: habanalabs device structure.
40  *
41  * Return: 0 for success, non-zero for failure.
42  */
43 int hl_mmu_init(struct hl_device *hdev)
44 {
45 	int rc = -EOPNOTSUPP;
46 
47 	if (hdev->mmu_disable)
48 		return 0;
49 
50 	mutex_init(&hdev->mmu_lock);
51 
52 	if (hdev->mmu_func[MMU_DR_PGT].init != NULL) {
53 		rc = hdev->mmu_func[MMU_DR_PGT].init(hdev);
54 		if (rc)
55 			return rc;
56 	}
57 
58 	if (hdev->mmu_func[MMU_HR_PGT].init != NULL) {
59 		rc = hdev->mmu_func[MMU_HR_PGT].init(hdev);
60 		if (rc)
61 			goto fini_dr_mmu;
62 	}
63 
64 	return 0;
65 
66 fini_dr_mmu:
67 	if (hdev->mmu_func[MMU_DR_PGT].fini != NULL)
68 		hdev->mmu_func[MMU_DR_PGT].fini(hdev);
69 
70 	return rc;
71 }
72 
73 /**
74  * hl_mmu_fini() - release the MMU module.
75  * @hdev: habanalabs device structure.
76  *
77  * This function does the following:
78  * - Disable MMU in H/W.
79  * - Free the pgt_infos pool.
80  *
81  * All contexts should be freed before calling this function.
82  */
83 void hl_mmu_fini(struct hl_device *hdev)
84 {
85 	if (hdev->mmu_disable)
86 		return;
87 
88 	if (hdev->mmu_func[MMU_DR_PGT].fini != NULL)
89 		hdev->mmu_func[MMU_DR_PGT].fini(hdev);
90 
91 	if (hdev->mmu_func[MMU_HR_PGT].fini != NULL)
92 		hdev->mmu_func[MMU_HR_PGT].fini(hdev);
93 
94 	mutex_destroy(&hdev->mmu_lock);
95 }
96 
97 /**
98  * hl_mmu_ctx_init() - initialize a context for using the MMU module.
99  * @ctx: pointer to the context structure to initialize.
100  *
101  * Initialize a mutex to protect the concurrent mapping flow, a hash to hold all
102  * page tables hops related to this context.
103  * Return: 0 on success, non-zero otherwise.
104  */
105 int hl_mmu_ctx_init(struct hl_ctx *ctx)
106 {
107 	struct hl_device *hdev = ctx->hdev;
108 	int rc = -EOPNOTSUPP;
109 
110 	if (hdev->mmu_disable)
111 		return 0;
112 
113 	if (hdev->mmu_func[MMU_DR_PGT].ctx_init != NULL) {
114 		rc = hdev->mmu_func[MMU_DR_PGT].ctx_init(ctx);
115 		if (rc)
116 			return rc;
117 	}
118 
119 	if (hdev->mmu_func[MMU_HR_PGT].ctx_init != NULL) {
120 		rc = hdev->mmu_func[MMU_HR_PGT].ctx_init(ctx);
121 		if (rc)
122 			goto fini_dr_ctx;
123 	}
124 
125 	return 0;
126 
127 fini_dr_ctx:
128 	if (hdev->mmu_func[MMU_DR_PGT].fini != NULL)
129 		hdev->mmu_func[MMU_DR_PGT].fini(hdev);
130 
131 	return rc;
132 }
133 
134 /*
135  * hl_mmu_ctx_fini - disable a ctx from using the mmu module
136  *
137  * @ctx: pointer to the context structure
138  *
139  * This function does the following:
140  * - Free any pgts which were not freed yet
141  * - Free the mutex
142  * - Free DRAM default page mapping hops
143  */
144 void hl_mmu_ctx_fini(struct hl_ctx *ctx)
145 {
146 	struct hl_device *hdev = ctx->hdev;
147 
148 	if (hdev->mmu_disable)
149 		return;
150 
151 	if (hdev->mmu_func[MMU_DR_PGT].ctx_fini != NULL)
152 		hdev->mmu_func[MMU_DR_PGT].ctx_fini(ctx);
153 
154 	if (hdev->mmu_func[MMU_HR_PGT].ctx_fini != NULL)
155 		hdev->mmu_func[MMU_HR_PGT].ctx_fini(ctx);
156 }
157 
158 /*
159  * hl_mmu_get_real_page_size - get real page size to use in map/unmap operation
160  *
161  * @hdev: pointer to device data.
162  * @mmu_prop: MMU properties.
163  * @page_size: page size
164  * @real_page_size: set here the actual page size to use for the operation
165  * @is_dram_addr: true if DRAM address, otherwise false.
166  *
167  * @return 0 on success, otherwise non 0 error code
168  *
169  * note that this is general implementation that can fit most MMU arch. but as this is used as an
170  * MMU function:
171  * 1. it shall not be called directly- only from mmu_func structure instance
172  * 2. each MMU may modify the implementation internally
173  */
174 int hl_mmu_get_real_page_size(struct hl_device *hdev, struct hl_mmu_properties *mmu_prop,
175 				u32 page_size, u32 *real_page_size, bool is_dram_addr)
176 {
177 	/*
178 	 * The H/W handles mapping of specific page sizes. Hence if the page
179 	 * size is bigger, we break it to sub-pages and map them separately.
180 	 */
181 	if ((page_size % mmu_prop->page_size) == 0) {
182 		*real_page_size = mmu_prop->page_size;
183 		return 0;
184 	}
185 
186 	dev_err(hdev->dev, "page size of %u is not %uKB aligned, can't map\n",
187 						page_size, mmu_prop->page_size >> 10);
188 
189 	return -EFAULT;
190 }
191 
192 static struct hl_mmu_properties *hl_mmu_get_prop(struct hl_device *hdev, u32 page_size,
193 							bool is_dram_addr)
194 {
195 	struct asic_fixed_properties *prop = &hdev->asic_prop;
196 
197 	if (is_dram_addr)
198 		return &prop->dmmu;
199 	else if ((page_size % prop->pmmu_huge.page_size) == 0)
200 		return &prop->pmmu_huge;
201 
202 	return &prop->pmmu;
203 }
204 
205 /*
206  * hl_mmu_unmap_page - unmaps a virtual addr
207  *
208  * @ctx: pointer to the context structure
209  * @virt_addr: virt addr to map from
210  * @page_size: size of the page to unmap
211  * @flush_pte: whether to do a PCI flush
212  *
213  * This function does the following:
214  * - Check that the virt addr is mapped
215  * - Unmap the virt addr and frees pgts if possible
216  * - Returns 0 on success, -EINVAL if the given addr is not mapped
217  *
218  * Because this function changes the page tables in the device and because it
219  * changes the MMU hash, it must be protected by a lock.
220  * However, because it maps only a single page, the lock should be implemented
221  * in a higher level in order to protect the entire mapping of the memory area
222  *
223  * For optimization reasons PCI flush may be requested once after unmapping of
224  * large area.
225  */
226 int hl_mmu_unmap_page(struct hl_ctx *ctx, u64 virt_addr, u32 page_size, bool flush_pte)
227 {
228 	struct hl_device *hdev = ctx->hdev;
229 	struct hl_mmu_properties *mmu_prop;
230 	struct hl_mmu_funcs *mmu_funcs;
231 	int i, pgt_residency, rc = 0;
232 	u32 real_page_size, npages;
233 	u64 real_virt_addr;
234 	bool is_dram_addr;
235 
236 	if (hdev->mmu_disable)
237 		return 0;
238 
239 	is_dram_addr = hl_is_dram_va(hdev, virt_addr);
240 	mmu_prop = hl_mmu_get_prop(hdev, page_size, is_dram_addr);
241 
242 	pgt_residency = mmu_prop->host_resident ? MMU_HR_PGT : MMU_DR_PGT;
243 	mmu_funcs = hl_mmu_get_funcs(hdev, pgt_residency, is_dram_addr);
244 
245 	rc = hdev->asic_funcs->mmu_get_real_page_size(hdev, mmu_prop, page_size, &real_page_size,
246 							is_dram_addr);
247 	if (rc)
248 		return rc;
249 
250 	npages = page_size / real_page_size;
251 	real_virt_addr = virt_addr;
252 
253 	for (i = 0 ; i < npages ; i++) {
254 		rc = mmu_funcs->unmap(ctx, real_virt_addr, is_dram_addr);
255 		if (rc)
256 			break;
257 
258 		real_virt_addr += real_page_size;
259 	}
260 
261 	if (flush_pte)
262 		mmu_funcs->flush(ctx);
263 
264 	if (trace_habanalabs_mmu_unmap_enabled() && !rc)
265 		trace_habanalabs_mmu_unmap(hdev->dev, virt_addr, 0, page_size, flush_pte);
266 
267 	return rc;
268 }
269 
270 /*
271  * hl_mmu_map_page - maps a virtual addr to physical addr
272  *
273  * @ctx: pointer to the context structure
274  * @virt_addr: virt addr to map from
275  * @phys_addr: phys addr to map to
276  * @page_size: physical page size
277  * @flush_pte: whether to do a PCI flush
278  *
279  * This function does the following:
280  * - Check that the virt addr is not mapped
281  * - Allocate pgts as necessary in order to map the virt addr to the phys
282  * - Returns 0 on success, -EINVAL if addr is already mapped, or -ENOMEM.
283  *
284  * Because this function changes the page tables in the device and because it
285  * changes the MMU hash, it must be protected by a lock.
286  * However, because it maps only a single page, the lock should be implemented
287  * in a higher level in order to protect the entire mapping of the memory area
288  *
289  * For optimization reasons PCI flush may be requested once after mapping of
290  * large area.
291  */
292 int hl_mmu_map_page(struct hl_ctx *ctx, u64 virt_addr, u64 phys_addr, u32 page_size,
293 			bool flush_pte)
294 {
295 	int i, rc, pgt_residency, mapped_cnt = 0;
296 	struct hl_device *hdev = ctx->hdev;
297 	struct hl_mmu_properties *mmu_prop;
298 	u64 real_virt_addr, real_phys_addr;
299 	struct hl_mmu_funcs *mmu_funcs;
300 	u32 real_page_size, npages;
301 	bool is_dram_addr;
302 
303 
304 	if (hdev->mmu_disable)
305 		return 0;
306 
307 	is_dram_addr = hl_is_dram_va(hdev, virt_addr);
308 	mmu_prop = hl_mmu_get_prop(hdev, page_size, is_dram_addr);
309 
310 	pgt_residency = mmu_prop->host_resident ? MMU_HR_PGT : MMU_DR_PGT;
311 	mmu_funcs = hl_mmu_get_funcs(hdev, pgt_residency, is_dram_addr);
312 
313 	rc = hdev->asic_funcs->mmu_get_real_page_size(hdev, mmu_prop, page_size, &real_page_size,
314 							is_dram_addr);
315 	if (rc)
316 		return rc;
317 
318 	/*
319 	 * Verify that the phys and virt addresses are aligned with the
320 	 * MMU page size (in dram this means checking the address and MMU
321 	 * after scrambling)
322 	 */
323 	if ((is_dram_addr &&
324 			((hdev->asic_funcs->scramble_addr(hdev, phys_addr) &
325 				(mmu_prop->page_size - 1)) ||
326 			(hdev->asic_funcs->scramble_addr(hdev, virt_addr) &
327 				(mmu_prop->page_size - 1)))) ||
328 		(!is_dram_addr && ((phys_addr & (real_page_size - 1)) ||
329 				(virt_addr & (real_page_size - 1)))))
330 		dev_crit(hdev->dev,
331 			"Mapping address 0x%llx with virtual address 0x%llx and page size of 0x%x is erroneous! Addresses must be divisible by page size",
332 			phys_addr, virt_addr, real_page_size);
333 
334 	npages = page_size / real_page_size;
335 	real_virt_addr = virt_addr;
336 	real_phys_addr = phys_addr;
337 
338 	for (i = 0 ; i < npages ; i++) {
339 		rc = mmu_funcs->map(ctx, real_virt_addr, real_phys_addr, real_page_size,
340 										is_dram_addr);
341 		if (rc)
342 			goto err;
343 
344 		real_virt_addr += real_page_size;
345 		real_phys_addr += real_page_size;
346 		mapped_cnt++;
347 	}
348 
349 	if (flush_pte)
350 		mmu_funcs->flush(ctx);
351 
352 	trace_habanalabs_mmu_map(hdev->dev, virt_addr, phys_addr, page_size, flush_pte);
353 
354 	return 0;
355 
356 err:
357 	real_virt_addr = virt_addr;
358 	for (i = 0 ; i < mapped_cnt ; i++) {
359 		if (mmu_funcs->unmap(ctx, real_virt_addr, is_dram_addr))
360 			dev_warn_ratelimited(hdev->dev,
361 				"failed to unmap va: 0x%llx\n", real_virt_addr);
362 
363 		real_virt_addr += real_page_size;
364 	}
365 
366 	mmu_funcs->flush(ctx);
367 
368 	return rc;
369 }
370 
371 /*
372  * hl_mmu_map_contiguous - implements a wrapper for hl_mmu_map_page
373  *                         for mapping contiguous physical memory
374  *
375  * @ctx: pointer to the context structure
376  * @virt_addr: virt addr to map from
377  * @phys_addr: phys addr to map to
378  * @size: size to map
379  *
380  */
381 int hl_mmu_map_contiguous(struct hl_ctx *ctx, u64 virt_addr,
382 					u64 phys_addr, u32 size)
383 {
384 	struct hl_device *hdev = ctx->hdev;
385 	struct asic_fixed_properties *prop = &hdev->asic_prop;
386 	u64 curr_va, curr_pa;
387 	u32 page_size;
388 	bool flush_pte;
389 	int rc = 0, off;
390 
391 	if (hl_mem_area_inside_range(virt_addr, size,
392 			prop->dmmu.start_addr, prop->dmmu.end_addr))
393 		page_size = prop->dmmu.page_size;
394 	else if (hl_mem_area_inside_range(virt_addr, size,
395 			prop->pmmu.start_addr, prop->pmmu.end_addr))
396 		page_size = prop->pmmu.page_size;
397 	else if (hl_mem_area_inside_range(virt_addr, size,
398 			prop->pmmu_huge.start_addr, prop->pmmu_huge.end_addr))
399 		page_size = prop->pmmu_huge.page_size;
400 	else
401 		return -EINVAL;
402 
403 	for (off = 0 ; off < size ; off += page_size) {
404 		curr_va = virt_addr + off;
405 		curr_pa = phys_addr + off;
406 		flush_pte = (off + page_size) >= size;
407 		rc = hl_mmu_map_page(ctx, curr_va, curr_pa, page_size,
408 								flush_pte);
409 		if (rc) {
410 			dev_err(hdev->dev,
411 				"Map failed for va 0x%llx to pa 0x%llx\n",
412 				curr_va, curr_pa);
413 			/* last mapping failed so don't try to unmap it - reduce off by page_size */
414 			off -= page_size;
415 			goto unmap;
416 		}
417 	}
418 
419 	return rc;
420 
421 unmap:
422 	for (; off >= 0 ; off -= page_size) {
423 		curr_va = virt_addr + off;
424 		flush_pte = (off - (s32) page_size) < 0;
425 		if (hl_mmu_unmap_page(ctx, curr_va, page_size, flush_pte))
426 			dev_warn_ratelimited(hdev->dev,
427 				"failed to unmap va 0x%llx\n", curr_va);
428 	}
429 
430 	return rc;
431 }
432 
433 /*
434  * hl_mmu_unmap_contiguous - implements a wrapper for hl_mmu_unmap_page
435  *                           for unmapping contiguous physical memory
436  *
437  * @ctx: pointer to the context structure
438  * @virt_addr: virt addr to unmap
439  * @size: size to unmap
440  *
441  */
442 int hl_mmu_unmap_contiguous(struct hl_ctx *ctx, u64 virt_addr, u32 size)
443 {
444 	struct hl_device *hdev = ctx->hdev;
445 	struct asic_fixed_properties *prop = &hdev->asic_prop;
446 	u64 curr_va;
447 	u32 page_size;
448 	bool flush_pte;
449 	int rc = 0, off;
450 
451 	if (hl_mem_area_inside_range(virt_addr, size,
452 			prop->dmmu.start_addr, prop->dmmu.end_addr))
453 		page_size = prop->dmmu.page_size;
454 	else if (hl_mem_area_inside_range(virt_addr, size,
455 			prop->pmmu.start_addr, prop->pmmu.end_addr))
456 		page_size = prop->pmmu.page_size;
457 	else if (hl_mem_area_inside_range(virt_addr, size,
458 			prop->pmmu_huge.start_addr, prop->pmmu_huge.end_addr))
459 		page_size = prop->pmmu_huge.page_size;
460 	else
461 		return -EINVAL;
462 
463 	for (off = 0 ; off < size ; off += page_size) {
464 		curr_va = virt_addr + off;
465 		flush_pte = (off + page_size) >= size;
466 		rc = hl_mmu_unmap_page(ctx, curr_va, page_size, flush_pte);
467 		if (rc)
468 			dev_warn_ratelimited(hdev->dev,
469 				"Unmap failed for va 0x%llx\n", curr_va);
470 	}
471 
472 	return rc;
473 }
474 
475 static void hl_mmu_pa_page_with_offset(struct hl_ctx *ctx, u64 virt_addr,
476 						struct hl_mmu_hop_info *hops,
477 						u64 *phys_addr)
478 {
479 	struct asic_fixed_properties *prop = &ctx->hdev->asic_prop;
480 	u64 offset_mask, addr_mask, hop_shift, tmp_phys_addr;
481 	struct hl_mmu_properties *mmu_prop;
482 
483 	/* last hop holds the phys address and flags */
484 	if (hops->unscrambled_paddr)
485 		tmp_phys_addr = hops->unscrambled_paddr;
486 	else
487 		tmp_phys_addr = hops->hop_info[hops->used_hops - 1].hop_pte_val;
488 
489 	if (hops->range_type == HL_VA_RANGE_TYPE_HOST_HUGE)
490 		mmu_prop = &prop->pmmu_huge;
491 	else if (hops->range_type == HL_VA_RANGE_TYPE_HOST)
492 		mmu_prop = &prop->pmmu;
493 	else /* HL_VA_RANGE_TYPE_DRAM */
494 		mmu_prop = &prop->dmmu;
495 
496 	if ((hops->range_type == HL_VA_RANGE_TYPE_DRAM) &&
497 			!is_power_of_2(prop->dram_page_size)) {
498 		u64 dram_page_size, dram_base, abs_phys_addr, abs_virt_addr,
499 			page_id, page_start;
500 		u32 page_off;
501 
502 		/*
503 		 * Bit arithmetic cannot be used for non power of two page
504 		 * sizes. In addition, since bit arithmetic is not used,
505 		 * we cannot ignore dram base. All that shall be considered.
506 		 */
507 
508 		dram_page_size = prop->dram_page_size;
509 		dram_base = prop->dram_base_address;
510 		abs_phys_addr = tmp_phys_addr - dram_base;
511 		abs_virt_addr = virt_addr - dram_base;
512 		page_id = DIV_ROUND_DOWN_ULL(abs_phys_addr, dram_page_size);
513 		page_start = page_id * dram_page_size;
514 		div_u64_rem(abs_virt_addr, dram_page_size, &page_off);
515 
516 		*phys_addr = page_start + page_off + dram_base;
517 	} else {
518 		/*
519 		 * find the correct hop shift field in hl_mmu_properties
520 		 * structure in order to determine the right masks
521 		 * for the page offset.
522 		 */
523 		hop_shift = mmu_prop->hop_shifts[hops->used_hops - 1];
524 		offset_mask = (1ull << hop_shift) - 1;
525 		addr_mask = ~(offset_mask);
526 		*phys_addr = (tmp_phys_addr & addr_mask) |
527 				(virt_addr & offset_mask);
528 	}
529 }
530 
531 int hl_mmu_va_to_pa(struct hl_ctx *ctx, u64 virt_addr, u64 *phys_addr)
532 {
533 	struct hl_mmu_hop_info hops;
534 	int rc;
535 
536 	memset(&hops, 0, sizeof(hops));
537 
538 	rc = hl_mmu_get_tlb_info(ctx, virt_addr, &hops);
539 	if (rc)
540 		return rc;
541 
542 	hl_mmu_pa_page_with_offset(ctx, virt_addr, &hops,  phys_addr);
543 
544 	return 0;
545 }
546 
547 int hl_mmu_get_tlb_info(struct hl_ctx *ctx, u64 virt_addr,
548 			struct hl_mmu_hop_info *hops)
549 {
550 	struct hl_device *hdev = ctx->hdev;
551 	struct asic_fixed_properties *prop;
552 	struct hl_mmu_properties *mmu_prop;
553 	struct hl_mmu_funcs *mmu_funcs;
554 	int pgt_residency, rc;
555 	bool is_dram_addr;
556 
557 	if (hdev->mmu_disable)
558 		return -EOPNOTSUPP;
559 
560 	prop = &hdev->asic_prop;
561 	hops->scrambled_vaddr = virt_addr;      /* assume no scrambling */
562 
563 	is_dram_addr = hl_mem_area_inside_range(virt_addr, prop->dmmu.page_size,
564 								prop->dmmu.start_addr,
565 								prop->dmmu.end_addr);
566 
567 	/* host-residency is the same in PMMU and PMMU huge, no need to distinguish here */
568 	mmu_prop = is_dram_addr ? &prop->dmmu : &prop->pmmu;
569 	pgt_residency = mmu_prop->host_resident ? MMU_HR_PGT : MMU_DR_PGT;
570 	mmu_funcs = hl_mmu_get_funcs(hdev, pgt_residency, is_dram_addr);
571 
572 	mutex_lock(&hdev->mmu_lock);
573 	rc = mmu_funcs->get_tlb_info(ctx, virt_addr, hops);
574 	mutex_unlock(&hdev->mmu_lock);
575 
576 	if (rc)
577 		return rc;
578 
579 	/* add page offset to physical address */
580 	if (hops->unscrambled_paddr)
581 		hl_mmu_pa_page_with_offset(ctx, virt_addr, hops, &hops->unscrambled_paddr);
582 
583 	return 0;
584 }
585 
586 int hl_mmu_if_set_funcs(struct hl_device *hdev)
587 {
588 	struct asic_fixed_properties *prop = &hdev->asic_prop;
589 
590 	if (hdev->mmu_disable)
591 		return 0;
592 
593 	switch (hdev->asic_type) {
594 	case ASIC_GOYA:
595 	case ASIC_GAUDI:
596 	case ASIC_GAUDI_SEC:
597 		hl_mmu_v1_set_funcs(hdev, &hdev->mmu_func[MMU_DR_PGT]);
598 		break;
599 	case ASIC_GAUDI2:
600 	case ASIC_GAUDI2B:
601 	case ASIC_GAUDI2C:
602 		hl_mmu_v2_set_funcs(hdev, &hdev->mmu_func[MMU_DR_PGT]);
603 		if (prop->pmmu.host_resident)
604 			hl_mmu_v2_hr_set_funcs(hdev, &hdev->mmu_func[MMU_HR_PGT]);
605 		break;
606 	default:
607 		dev_err(hdev->dev, "Unrecognized ASIC type %d\n",
608 			hdev->asic_type);
609 		return -EOPNOTSUPP;
610 	}
611 
612 	return 0;
613 }
614 
615 /**
616  * hl_mmu_scramble_addr() - The generic mmu address scrambling routine.
617  * @hdev: pointer to device data.
618  * @addr: The address to scramble.
619  *
620  * Return: The scrambled address.
621  */
622 u64 hl_mmu_scramble_addr(struct hl_device *hdev, u64 addr)
623 {
624 	return addr;
625 }
626 
627 /**
628  * hl_mmu_descramble_addr() - The generic mmu address descrambling
629  * routine.
630  * @hdev: pointer to device data.
631  * @addr: The address to descramble.
632  *
633  * Return: The un-scrambled address.
634  */
635 u64 hl_mmu_descramble_addr(struct hl_device *hdev, u64 addr)
636 {
637 	return addr;
638 }
639 
640 int hl_mmu_invalidate_cache(struct hl_device *hdev, bool is_hard, u32 flags)
641 {
642 	int rc;
643 
644 	rc = hdev->asic_funcs->mmu_invalidate_cache(hdev, is_hard, flags);
645 	if (rc)
646 		dev_err_ratelimited(hdev->dev,
647 				"%s cache invalidation failed, rc=%d\n",
648 				flags == VM_TYPE_USERPTR ? "PMMU" : "HMMU", rc);
649 
650 	return rc;
651 }
652 
653 int hl_mmu_invalidate_cache_range(struct hl_device *hdev, bool is_hard,
654 					u32 flags, u32 asid, u64 va, u64 size)
655 {
656 	int rc;
657 
658 	rc = hdev->asic_funcs->mmu_invalidate_cache_range(hdev, is_hard, flags,
659 								asid, va, size);
660 	if (rc)
661 		dev_err_ratelimited(hdev->dev,
662 				"%s cache range invalidation failed: va=%#llx, size=%llu, rc=%d",
663 				flags == VM_TYPE_USERPTR ? "PMMU" : "HMMU", va, size, rc);
664 
665 	return rc;
666 }
667 
668 static void hl_mmu_prefetch_work_function(struct work_struct *work)
669 {
670 	struct hl_prefetch_work *pfw = container_of(work, struct hl_prefetch_work, prefetch_work);
671 	struct hl_ctx *ctx = pfw->ctx;
672 	struct hl_device *hdev = ctx->hdev;
673 
674 	if (!hl_device_operational(hdev, NULL))
675 		goto put_ctx;
676 
677 	mutex_lock(&hdev->mmu_lock);
678 
679 	hdev->asic_funcs->mmu_prefetch_cache_range(ctx, pfw->flags, pfw->asid, pfw->va, pfw->size);
680 
681 	mutex_unlock(&hdev->mmu_lock);
682 
683 put_ctx:
684 	/*
685 	 * context was taken in the common mmu prefetch function- see comment there about
686 	 * context handling.
687 	 */
688 	hl_ctx_put(ctx);
689 	kfree(pfw);
690 }
691 
692 int hl_mmu_prefetch_cache_range(struct hl_ctx *ctx, u32 flags, u32 asid, u64 va, u64 size)
693 {
694 	struct hl_prefetch_work *handle_prefetch_work;
695 
696 	handle_prefetch_work = kmalloc(sizeof(*handle_prefetch_work), GFP_KERNEL);
697 	if (!handle_prefetch_work)
698 		return -ENOMEM;
699 
700 	INIT_WORK(&handle_prefetch_work->prefetch_work, hl_mmu_prefetch_work_function);
701 	handle_prefetch_work->ctx = ctx;
702 	handle_prefetch_work->va = va;
703 	handle_prefetch_work->size = size;
704 	handle_prefetch_work->flags = flags;
705 	handle_prefetch_work->asid = asid;
706 
707 	/*
708 	 * as actual prefetch is done in a WQ we must get the context (and put it
709 	 * at the end of the work function)
710 	 */
711 	hl_ctx_get(ctx);
712 	queue_work(ctx->hdev->prefetch_wq, &handle_prefetch_work->prefetch_work);
713 
714 	return 0;
715 }
716 
717 u64 hl_mmu_get_next_hop_addr(struct hl_ctx *ctx, u64 curr_pte)
718 {
719 	return (curr_pte & PAGE_PRESENT_MASK) ? (curr_pte & HOP_PHYS_ADDR_MASK) : ULLONG_MAX;
720 }
721 
722 /**
723  * hl_mmu_get_hop_pte_phys_addr() - extract PTE address from HOP
724  * @ctx: pointer to the context structure to initialize.
725  * @mmu_prop: MMU properties.
726  * @hop_idx: HOP index.
727  * @hop_addr: HOP address.
728  * @virt_addr: virtual address for the translation.
729  *
730  * @return the matching PTE value on success, otherwise U64_MAX.
731  */
732 u64 hl_mmu_get_hop_pte_phys_addr(struct hl_ctx *ctx, struct hl_mmu_properties *mmu_prop,
733 					u8 hop_idx, u64 hop_addr, u64 virt_addr)
734 {
735 	u64 mask, shift;
736 
737 	if (hop_idx >= mmu_prop->num_hops) {
738 		dev_err_ratelimited(ctx->hdev->dev, "Invalid hop index %d\n", hop_idx);
739 		return U64_MAX;
740 	}
741 
742 	shift = mmu_prop->hop_shifts[hop_idx];
743 	mask = mmu_prop->hop_masks[hop_idx];
744 
745 	return hop_addr + ctx->hdev->asic_prop.mmu_pte_size * ((virt_addr & mask) >> shift);
746 }
747 
748 static void mmu_dma_mem_free_from_chunk(struct gen_pool *pool,
749 					struct gen_pool_chunk *chunk,
750 					void *data)
751 {
752 	struct hl_device *hdev = data;
753 
754 	hl_asic_dma_free_coherent(hdev, (chunk->end_addr - chunk->start_addr) + 1,
755 					(void *)chunk->start_addr, chunk->phys_addr);
756 }
757 
758 void hl_mmu_hr_flush(struct hl_ctx *ctx)
759 {
760 	/* a flush operation requires memory barrier */
761 	mb();
762 }
763 
764 /**
765  * hl_mmu_hr_pool_destroy() - destroy genpool
766  * @hdev: habanalabs device structure.
767  * @hr_priv: MMU HR private data.
768  * @hop_table_size: HOP table size.
769  *
770  * This function does the following:
771  * - free entries allocated for shadow HOP0
772  * - free pool chunks
773  * - free pool
774  */
775 static void hl_mmu_hr_pool_destroy(struct hl_device *hdev, struct hl_mmu_hr_priv *hr_priv,
776 					u32 hop_table_size)
777 {
778 	struct asic_fixed_properties *prop = &hdev->asic_prop;
779 	struct gen_pool **pool = &hr_priv->mmu_pgt_pool;
780 	struct pgt_info *hop0_pgt;
781 	int asid;
782 
783 	if (ZERO_OR_NULL_PTR(*pool))
784 		return;
785 
786 	/* Free the Fixed allocation of HOPs0 */
787 	if (hr_priv->mmu_asid_hop0) {
788 		for (asid = 0 ; asid < prop->max_asid ; asid++) {
789 			hop0_pgt = &hr_priv->mmu_asid_hop0[asid];
790 			if (ZERO_OR_NULL_PTR(hop0_pgt->virt_addr))
791 				continue;
792 
793 			gen_pool_free(*pool, (uintptr_t) hop0_pgt->virt_addr, hop_table_size);
794 		}
795 	}
796 
797 	gen_pool_for_each_chunk(*pool, mmu_dma_mem_free_from_chunk, hdev);
798 	gen_pool_destroy(*pool);
799 
800 	/* Make sure that if we arrive here again without init was called we
801 	 * won't cause kernel panic. This can happen for example if we fail
802 	 * during hard reset code at certain points
803 	 */
804 	*pool = NULL;
805 }
806 
807 /**
808  * hl_mmu_hr_init() - initialize the MMU module.
809  * @hdev: habanalabs device structure.
810  * @hr_priv: MMU HR private data.
811  * @hop_table_size: HOP table size.
812  * @pgt_size: memory size allocated for the page table
813  *
814  * @return 0 on success otherwise non-zero error code
815  *
816  * This function does the following:
817  * - Create a pool of pages for pgt_infos.
818  * - Create a shadow table for pgt
819  */
820 int hl_mmu_hr_init(struct hl_device *hdev, struct hl_mmu_hr_priv *hr_priv, u32 hop_table_size,
821 			u64 pgt_size)
822 {
823 	struct asic_fixed_properties *prop = &hdev->asic_prop;
824 	size_t pool_chunk_size = SZ_4M;
825 	struct pgt_info *hop0_pgt;
826 	dma_addr_t dma_addr;
827 	u64 virt_addr;
828 	int i, rc;
829 
830 	/*
831 	 * we set alloc size as PAGE_SIZE (sine dma_alloc_coherent allocation order/size is
832 	 * PAGE_SHIFT/PAGE_SIZE) in order to be able to control the allocations alignment.
833 	 * This way we can call "DMA alloc align" according to dma_alloc granularity and supply
834 	 * allocations with higher-order alignment restrictions
835 	 */
836 	hr_priv->mmu_pgt_pool = gen_pool_create(PAGE_SHIFT, -1);
837 	if (ZERO_OR_NULL_PTR(hr_priv->mmu_pgt_pool)) {
838 		dev_err(hdev->dev, "Failed to create hr page pool\n");
839 		return -ENOMEM;
840 	}
841 
842 	hr_priv->mmu_asid_hop0 = kvcalloc(prop->max_asid, sizeof(struct pgt_info), GFP_KERNEL);
843 	if (ZERO_OR_NULL_PTR(hr_priv->mmu_asid_hop0)) {
844 		dev_err(hdev->dev, "Failed to allocate hr-mmu hop0 table\n");
845 		rc = -ENOMEM;
846 		goto destroy_mmu_pgt_pool;
847 	}
848 
849 	for (i = 0 ; i < pgt_size ; i += pool_chunk_size) {
850 		virt_addr = (uintptr_t) hl_asic_dma_alloc_coherent(hdev, pool_chunk_size,
851 									&dma_addr,
852 									GFP_KERNEL | __GFP_ZERO);
853 		if (ZERO_OR_NULL_PTR(virt_addr)) {
854 			dev_err(hdev->dev,
855 				"Failed to allocate memory for host-resident page pool\n");
856 			rc = -ENOMEM;
857 			goto destroy_mmu_pgt_pool;
858 		}
859 
860 		rc = gen_pool_add_virt(hr_priv->mmu_pgt_pool, virt_addr, (phys_addr_t) dma_addr,
861 						pool_chunk_size, -1);
862 		if (rc) {
863 			dev_err(hdev->dev, "Failed to fill host-resident page pool\n");
864 			goto destroy_mmu_pgt_pool;
865 		}
866 	}
867 
868 	for (i = 0 ; i < prop->max_asid ; i++) {
869 		hop0_pgt = &hr_priv->mmu_asid_hop0[i];
870 		hop0_pgt->virt_addr = (uintptr_t)
871 					gen_pool_dma_zalloc_align(hr_priv->mmu_pgt_pool,
872 								hop_table_size,
873 								(dma_addr_t *) &hop0_pgt->phys_addr,
874 								hop_table_size);
875 		if (!hop0_pgt->virt_addr) {
876 			dev_err(hdev->dev, "Failed to allocate HOP from pgt pool\n");
877 			rc = -ENOMEM;
878 			goto destroy_mmu_pgt_pool;
879 		}
880 	}
881 
882 	/* MMU H/W init will be done in device hw_init() */
883 
884 	return 0;
885 
886 destroy_mmu_pgt_pool:
887 	hl_mmu_hr_pool_destroy(hdev, hr_priv, hop_table_size);
888 	if (!ZERO_OR_NULL_PTR(hr_priv->mmu_asid_hop0))
889 		kvfree(hr_priv->mmu_asid_hop0);
890 
891 	return rc;
892 }
893 
894 /**
895  * hl_mmu_hr_fini() - release the MMU module.
896  * @hdev: habanalabs device structure.
897  * @hr_priv: MMU host resident private info.
898  * @hop_table_size: HOP table size
899  *
900  * This function does the following:
901  * - Disable MMU in H/W.
902  * - Free the pgt_infos pool.
903  *
904  * All contexts should be freed before calling this function.
905  */
906 void hl_mmu_hr_fini(struct hl_device *hdev, struct hl_mmu_hr_priv *hr_priv, u32 hop_table_size)
907 {
908 	/* MMU H/W fini was already done in device hw_fini() */
909 
910 	hl_mmu_hr_pool_destroy(hdev, hr_priv, hop_table_size);
911 
912 	if (!ZERO_OR_NULL_PTR(hr_priv->mmu_asid_hop0)) {
913 		kvfree(hr_priv->mmu_asid_hop0);
914 
915 		/* Make sure that if we arrive here again without init was
916 		 * called we won't cause kernel panic. This can happen for
917 		 * example if we fail during hard reset code at certain points
918 		 */
919 		hr_priv->mmu_asid_hop0 = NULL;
920 	}
921 }
922 
923 /**
924  * hl_mmu_hr_free_hop_remove_pgt() - free HOP and remove PGT from hash
925  * @pgt_info: page table info structure.
926  * @hr_priv: MMU HR private data.
927  * @hop_table_size: HOP table size.
928  */
929 void hl_mmu_hr_free_hop_remove_pgt(struct pgt_info *pgt_info, struct hl_mmu_hr_priv *hr_priv,
930 					u32 hop_table_size)
931 {
932 	gen_pool_free(hr_priv->mmu_pgt_pool, pgt_info->virt_addr, hop_table_size);
933 	hash_del(&pgt_info->node);
934 	kfree(pgt_info);
935 }
936 
937 /**
938  * hl_mmu_hr_pte_phys_to_virt() - translate PTE phys addr to virt addr
939  * @ctx: pointer to the context structure
940  * @pgt: pgt_info for the HOP hosting the PTE
941  * @phys_pte_addr: phys address of the PTE
942  * @hop_table_size: HOP table size
943  *
944  * @return PTE virtual address
945  *
946  * The function use the pgt_info to get HOP base virt addr and obtain the PTE's virt addr
947  * by adding the PTE offset.
948  */
949 u64 hl_mmu_hr_pte_phys_to_virt(struct hl_ctx *ctx, struct pgt_info *pgt,
950 							u64 phys_pte_addr, u32 hop_table_size)
951 {
952 	u64 page_mask = (hop_table_size - 1);
953 	u64 pte_offset = phys_pte_addr & page_mask;
954 
955 	return pgt->virt_addr + pte_offset;
956 }
957 
958 /**
959  * hl_mmu_hr_write_pte() - write HR PTE
960  * @ctx: pointer to the context structure
961  * @pgt_info: HOP's page table info structure
962  * @phys_pte_addr: phys PTE address
963  * @val: raw PTE data
964  * @hop_table_size: HOP table size
965  */
966 void hl_mmu_hr_write_pte(struct hl_ctx *ctx, struct pgt_info *pgt_info, u64 phys_pte_addr,
967 								u64 val, u32 hop_table_size)
968 {
969 	/*
970 	 * The value to write is the phys address of the next hop +
971 	 * flags at the 12 LSBs.
972 	 */
973 	u64 virt_addr = hl_mmu_hr_pte_phys_to_virt(ctx, pgt_info, phys_pte_addr, hop_table_size);
974 
975 	*((u64 *) (uintptr_t) virt_addr) = val;
976 }
977 
978 /**
979  * hl_mmu_hr_clear_pte() - clear HR PTE
980  * @ctx: pointer to the context structure
981  * @pgt_info: HOP's page table info structure
982  * @phys_pte_addr: phys PTE address
983  * @hop_table_size: HOP table size
984  */
985 void hl_mmu_hr_clear_pte(struct hl_ctx *ctx, struct pgt_info *pgt_info, u64 phys_pte_addr,
986 						u32 hop_table_size)
987 {
988 	/* no need to transform the value to physical address */
989 	hl_mmu_hr_write_pte(ctx, pgt_info, phys_pte_addr, 0, hop_table_size);
990 }
991 
992 /**
993  * hl_mmu_hr_put_pte() - put HR PTE and remove it if necessary (no more PTEs)
994  * @ctx: pointer to the context structure
995  * @pgt_info: HOP's page table info structure
996  * @hr_priv: HR MMU private info
997  * @hop_table_size: HOP table size
998  *
999  * @return number of PTEs still in the HOP
1000  */
1001 int hl_mmu_hr_put_pte(struct hl_ctx *ctx, struct pgt_info *pgt_info,
1002 						struct hl_mmu_hr_priv *hr_priv,
1003 						u32 hop_table_size)
1004 {
1005 	int num_of_ptes_left;
1006 
1007 	pgt_info->num_of_ptes--;
1008 
1009 	/*
1010 	 * Need to save the number of ptes left because free_hop might free
1011 	 * the pgt_info
1012 	 */
1013 	num_of_ptes_left = pgt_info->num_of_ptes;
1014 	if (!num_of_ptes_left)
1015 		hl_mmu_hr_free_hop_remove_pgt(pgt_info, hr_priv, hop_table_size);
1016 
1017 	return num_of_ptes_left;
1018 }
1019 
1020 /**
1021  * hl_mmu_hr_get_pte() - increase PGT PTE count
1022  * @ctx: pointer to the context structure
1023  * @hr_func: host resident functions
1024  * @phys_hop_addr: HOP phys address
1025  */
1026 void hl_mmu_hr_get_pte(struct hl_ctx *ctx, struct hl_hr_mmu_funcs *hr_func, u64 phys_hop_addr)
1027 {
1028 	hr_func->get_pgt_info(ctx, phys_hop_addr)->num_of_ptes++;
1029 }
1030 
1031 /**
1032  * hl_mmu_hr_get_next_hop_pgt_info() - get pgt_info structure for the next HOP
1033  * @ctx: pointer to the context structure.
1034  * @hr_func: host resident functions.
1035  * @curr_pte: current PTE value.
1036  *
1037  * @return pgt_info structure on success, otherwise NULL.
1038  */
1039 struct pgt_info *hl_mmu_hr_get_next_hop_pgt_info(struct hl_ctx *ctx,
1040 							struct hl_hr_mmu_funcs *hr_func,
1041 							u64 curr_pte)
1042 {
1043 	u64 next_hop_phys_addr = hl_mmu_get_next_hop_addr(ctx, curr_pte);
1044 
1045 	if (next_hop_phys_addr == ULLONG_MAX)
1046 		return NULL;
1047 
1048 	return hr_func->get_pgt_info(ctx, next_hop_phys_addr);
1049 }
1050 
1051 /**
1052  * hl_mmu_hr_alloc_hop() - allocate HOP
1053  * @ctx: pointer to the context structure.
1054  * @hr_priv: host resident private info structure.
1055  * @hr_func: host resident functions.
1056  * @mmu_prop: MMU properties.
1057  *
1058  * @return pgt_info structure associated with the allocated HOP on success, otherwise NULL.
1059  */
1060 struct pgt_info *hl_mmu_hr_alloc_hop(struct hl_ctx *ctx, struct hl_mmu_hr_priv *hr_priv,
1061 							struct hl_hr_mmu_funcs *hr_func,
1062 							struct hl_mmu_properties *mmu_prop)
1063 {
1064 	struct hl_device *hdev = ctx->hdev;
1065 	struct pgt_info *pgt_info;
1066 	dma_addr_t phys_addr;
1067 	void *virt_addr;
1068 	int i, retry = 1;
1069 
1070 	pgt_info = kmalloc(sizeof(*pgt_info), GFP_KERNEL);
1071 	if (!pgt_info)
1072 		return NULL;
1073 
1074 	for (i = 0; i <= retry; i++) {
1075 		virt_addr = gen_pool_dma_zalloc_align(hr_priv->mmu_pgt_pool,
1076 							mmu_prop->hop_table_size,
1077 							&phys_addr,
1078 							mmu_prop->hop_table_size);
1079 		if (virt_addr)
1080 			break;
1081 
1082 		/* No memory in pool - get some and try again */
1083 		virt_addr = hl_asic_dma_alloc_coherent(hdev, SZ_2M, &phys_addr,
1084 							GFP_KERNEL | __GFP_ZERO);
1085 		if (ZERO_OR_NULL_PTR(virt_addr))
1086 			break;
1087 
1088 		if (gen_pool_add_virt(hr_priv->mmu_pgt_pool, (unsigned long)virt_addr,
1089 								phys_addr, SZ_2M, -1)) {
1090 			hl_asic_dma_free_coherent(hdev, SZ_2M, virt_addr, phys_addr);
1091 			virt_addr = NULL;
1092 			break;
1093 		}
1094 	}
1095 
1096 	if (ZERO_OR_NULL_PTR(virt_addr)) {
1097 		dev_err(hdev->dev, "failed to allocate page\n");
1098 		goto pool_alloc_err;
1099 	}
1100 
1101 	pgt_info->phys_addr = phys_addr;
1102 	pgt_info->shadow_addr = (unsigned long) NULL;
1103 	pgt_info->virt_addr = (unsigned long)virt_addr;
1104 	pgt_info->ctx = ctx;
1105 	pgt_info->num_of_ptes = 0;
1106 	hr_func->add_pgt_info(ctx, pgt_info, phys_addr);
1107 
1108 	return pgt_info;
1109 
1110 pool_alloc_err:
1111 	kfree(pgt_info);
1112 
1113 	return NULL;
1114 }
1115 
1116 /**
1117  * hl_mmu_hr_get_alloc_next_hop() - get the next HOP, allocate it if it does not exist
1118  * @ctx: pointer to the context structure.
1119  * @hr_priv: host resident private info structure.
1120  * @hr_func: host resident functions.
1121  * @mmu_prop: MMU properties.
1122  * @curr_pte: current PTE value.
1123  * @is_new_hop: set to true if HOP is new (caller responsibility to set it to false).
1124  *
1125  * @return pgt_info structure associated with the allocated HOP on success, otherwise NULL.
1126  */
1127 struct pgt_info *hl_mmu_hr_get_alloc_next_hop(struct hl_ctx *ctx,
1128 							struct hl_mmu_hr_priv *hr_priv,
1129 							struct hl_hr_mmu_funcs *hr_func,
1130 							struct hl_mmu_properties *mmu_prop,
1131 							u64 curr_pte, bool *is_new_hop)
1132 {
1133 	u64 hop_addr = hl_mmu_get_next_hop_addr(ctx, curr_pte);
1134 
1135 	if (hop_addr != ULLONG_MAX)
1136 		return hr_func->get_pgt_info(ctx, hop_addr);
1137 
1138 	*is_new_hop = true;
1139 	return hl_mmu_hr_alloc_hop(ctx, hr_priv, hr_func, mmu_prop);
1140 }
1141 
1142 /**
1143  * hl_mmu_hr_get_tlb_info() - get the TLB info (info for a specific mapping)
1144  * @ctx: pointer to the context structure.
1145  * @virt_addr: the virt address for which to get info.
1146  * @hops: HOPs info structure.
1147  * @hr_func: host resident functions.
1148  *
1149  * @return 0 on success, otherwise non 0 error code..
1150  */
1151 int hl_mmu_hr_get_tlb_info(struct hl_ctx *ctx, u64 virt_addr, struct hl_mmu_hop_info *hops,
1152 								struct hl_hr_mmu_funcs *hr_func)
1153 {
1154 	/* using 6 HOPs as this is the maximum number of HOPs */
1155 	struct pgt_info *hops_pgt_info[MMU_ARCH_6_HOPS] = { NULL };
1156 	struct hl_device *hdev = ctx->hdev;
1157 	struct hl_mmu_properties *mmu_prop;
1158 	int rc, i, used_hops;
1159 	bool is_huge;
1160 
1161 	rc = hr_func->get_tlb_mapping_params(hdev, &mmu_prop, hops, virt_addr, &is_huge);
1162 	if (rc)
1163 		return rc;
1164 
1165 	used_hops = mmu_prop->num_hops;
1166 
1167 	/* huge pages use one less hop */
1168 	if (is_huge)
1169 		used_hops--;
1170 
1171 	hops->scrambled_vaddr = hdev->asic_funcs->scramble_addr(hdev, virt_addr);
1172 
1173 	for (i = 0 ; i < used_hops ; i++) {
1174 		if (i == 0)
1175 			hops_pgt_info[i] = hr_func->get_hop0_pgt_info(ctx);
1176 		else
1177 			hops_pgt_info[i] = hl_mmu_hr_get_next_hop_pgt_info(ctx, hr_func,
1178 								hops->hop_info[i - 1].hop_pte_val);
1179 
1180 		if (!hops_pgt_info[i])
1181 			return -EFAULT;
1182 
1183 		hops->hop_info[i].hop_addr = hops_pgt_info[i]->phys_addr;
1184 		hops->hop_info[i].hop_pte_addr =
1185 				hl_mmu_get_hop_pte_phys_addr(ctx, mmu_prop, i,
1186 								hops->hop_info[i].hop_addr,
1187 								hops->scrambled_vaddr);
1188 		hops->hop_info[i].hop_pte_val = *(u64 *) (uintptr_t)
1189 						hl_mmu_hr_pte_phys_to_virt(ctx, hops_pgt_info[i],
1190 								hops->hop_info[i].hop_pte_addr,
1191 								mmu_prop->hop_table_size);
1192 
1193 		if (!(hops->hop_info[i].hop_pte_val & PAGE_PRESENT_MASK))
1194 			return -EFAULT;
1195 
1196 		if (hops->hop_info[i].hop_pte_val & mmu_prop->last_mask)
1197 			break;
1198 	}
1199 
1200 	/* if passed over all hops then no last hop was found */
1201 	if (i == mmu_prop->num_hops)
1202 		return -EFAULT;
1203 
1204 	if (hops->scrambled_vaddr != virt_addr)
1205 		hops->unscrambled_paddr = hdev->asic_funcs->descramble_addr
1206 				(hdev, hops->hop_info[i].hop_pte_val);
1207 	else
1208 		hops->unscrambled_paddr = hops->hop_info[i].hop_pte_val;
1209 
1210 	hops->used_hops = i + 1;
1211 
1212 	return 0;
1213 }
1214 
1215 struct pgt_info *hl_mmu_dr_get_pgt_info(struct hl_ctx *ctx, u64 hop_addr)
1216 {
1217 	struct pgt_info *pgt_info = NULL;
1218 
1219 	hash_for_each_possible(ctx->mmu_shadow_hash, pgt_info, node,
1220 			(unsigned long) hop_addr)
1221 		if (hop_addr == pgt_info->shadow_addr)
1222 			break;
1223 
1224 	return pgt_info;
1225 }
1226 
1227 void hl_mmu_dr_free_hop(struct hl_ctx *ctx, u64 hop_addr)
1228 {
1229 	struct pgt_info *pgt_info = hl_mmu_dr_get_pgt_info(ctx, hop_addr);
1230 
1231 	hl_mmu_dr_free_pgt_node(ctx, pgt_info);
1232 }
1233 
1234 void hl_mmu_dr_free_pgt_node(struct hl_ctx *ctx, struct pgt_info *pgt_info)
1235 {
1236 	struct hl_device *hdev = ctx->hdev;
1237 
1238 	gen_pool_free(hdev->mmu_priv.dr.mmu_pgt_pool, pgt_info->phys_addr,
1239 			hdev->asic_prop.dmmu.hop_table_size);
1240 	hash_del(&pgt_info->node);
1241 	kfree((u64 *) (uintptr_t) pgt_info->shadow_addr);
1242 	kfree(pgt_info);
1243 }
1244 
1245 u64 hl_mmu_dr_get_phys_hop0_addr(struct hl_ctx *ctx)
1246 {
1247 	return ctx->hdev->asic_prop.mmu_pgt_addr +
1248 			(ctx->asid * ctx->hdev->asic_prop.dmmu.hop_table_size);
1249 }
1250 
1251 u64 hl_mmu_dr_get_hop0_addr(struct hl_ctx *ctx)
1252 {
1253 	return (u64) (uintptr_t) ctx->hdev->mmu_priv.dr.mmu_shadow_hop0 +
1254 			(ctx->asid * ctx->hdev->asic_prop.dmmu.hop_table_size);
1255 }
1256 
1257 u64 hl_mmu_dr_get_phys_addr(struct hl_ctx *ctx, u64 shadow_addr)
1258 {
1259 	u64 page_mask = ctx->hdev->asic_prop.dmmu.hop_table_size - 1;
1260 	u64 shadow_hop_addr = shadow_addr & (~page_mask);
1261 	u64 pte_offset = shadow_addr & page_mask;
1262 	u64 phys_hop_addr;
1263 
1264 	if (shadow_hop_addr != hl_mmu_dr_get_hop0_addr(ctx))
1265 		phys_hop_addr = hl_mmu_dr_get_pgt_info(ctx, shadow_hop_addr)->phys_addr;
1266 	else
1267 		phys_hop_addr = hl_mmu_dr_get_phys_hop0_addr(ctx);
1268 
1269 	return phys_hop_addr + pte_offset;
1270 }
1271 
1272 void hl_mmu_dr_write_pte(struct hl_ctx *ctx, u64 shadow_pte_addr, u64 val)
1273 {
1274 	u64 phys_val = hl_mmu_dr_get_phys_addr(ctx, val);
1275 
1276 	ctx->hdev->asic_funcs->write_pte(ctx->hdev, hl_mmu_dr_get_phys_addr(ctx, shadow_pte_addr),
1277 					phys_val);
1278 
1279 	*(u64 *) (uintptr_t) shadow_pte_addr = val;
1280 }
1281 
1282 void hl_mmu_dr_write_final_pte(struct hl_ctx *ctx, u64 shadow_pte_addr, u64 val)
1283 {
1284 	ctx->hdev->asic_funcs->write_pte(ctx->hdev,
1285 				hl_mmu_dr_get_phys_addr(ctx, shadow_pte_addr), val);
1286 	*(u64 *) (uintptr_t) shadow_pte_addr = val;
1287 }
1288 
1289 void hl_mmu_dr_clear_pte(struct hl_ctx *ctx, u64 pte_addr)
1290 {
1291 	hl_mmu_dr_write_final_pte(ctx, pte_addr, 0);
1292 }
1293 
1294 void hl_mmu_dr_get_pte(struct hl_ctx *ctx, u64 hop_addr)
1295 {
1296 	hl_mmu_dr_get_pgt_info(ctx, hop_addr)->num_of_ptes++;
1297 }
1298 
1299 int hl_mmu_dr_put_pte(struct hl_ctx *ctx, u64 hop_addr)
1300 {
1301 	struct pgt_info *pgt_info = hl_mmu_dr_get_pgt_info(ctx, hop_addr);
1302 	int num_of_ptes_left;
1303 
1304 	pgt_info->num_of_ptes--;
1305 
1306 	/*
1307 	 * Need to save the number of ptes left because hl_mmu_free_hop might free
1308 	 * the pgt_info
1309 	 */
1310 	num_of_ptes_left = pgt_info->num_of_ptes;
1311 	if (!num_of_ptes_left)
1312 		hl_mmu_dr_free_pgt_node(ctx, pgt_info);
1313 
1314 	return num_of_ptes_left;
1315 }
1316 
1317 u64 hl_mmu_dr_alloc_hop(struct hl_ctx *ctx)
1318 {
1319 	struct hl_device *hdev = ctx->hdev;
1320 	struct asic_fixed_properties *prop = &hdev->asic_prop;
1321 	struct pgt_info *pgt_info;
1322 	u64 phys_addr, shadow_addr;
1323 
1324 	pgt_info = kmalloc(sizeof(*pgt_info), GFP_KERNEL);
1325 	if (!pgt_info)
1326 		return ULLONG_MAX;
1327 
1328 	phys_addr = (u64) gen_pool_alloc(hdev->mmu_priv.dr.mmu_pgt_pool,
1329 					prop->dmmu.hop_table_size);
1330 	if (!phys_addr) {
1331 		dev_err(hdev->dev, "failed to allocate page\n");
1332 		goto pool_add_err;
1333 	}
1334 
1335 	shadow_addr = (u64) (uintptr_t) kzalloc(prop->dmmu.hop_table_size,
1336 						GFP_KERNEL);
1337 	if (!shadow_addr)
1338 		goto shadow_err;
1339 
1340 	pgt_info->phys_addr = phys_addr;
1341 	pgt_info->shadow_addr = shadow_addr;
1342 	pgt_info->ctx = ctx;
1343 	pgt_info->num_of_ptes = 0;
1344 	hash_add(ctx->mmu_shadow_hash, &pgt_info->node, shadow_addr);
1345 
1346 	return shadow_addr;
1347 
1348 shadow_err:
1349 	gen_pool_free(hdev->mmu_priv.dr.mmu_pgt_pool,
1350 			phys_addr, prop->dmmu.hop_table_size);
1351 pool_add_err:
1352 	kfree(pgt_info);
1353 
1354 	return ULLONG_MAX;
1355 }
1356 
1357 u64 hl_mmu_dr_get_alloc_next_hop_addr(struct hl_ctx *ctx, u64 curr_pte, bool *is_new_hop)
1358 {
1359 	u64 hop_addr = hl_mmu_get_next_hop_addr(ctx, curr_pte);
1360 
1361 	if (hop_addr == ULLONG_MAX) {
1362 		hop_addr = hl_mmu_dr_alloc_hop(ctx);
1363 		*is_new_hop = (hop_addr != ULLONG_MAX);
1364 	}
1365 
1366 	return hop_addr;
1367 }
1368 
1369 void hl_mmu_dr_flush(struct hl_ctx *ctx)
1370 {
1371 	/* flush all writes from all cores to reach PCI */
1372 	mb();
1373 	ctx->hdev->asic_funcs->read_pte(ctx->hdev, hl_mmu_dr_get_phys_hop0_addr(ctx));
1374 }
1375 
1376 int hl_mmu_dr_init(struct hl_device *hdev)
1377 {
1378 	struct asic_fixed_properties *prop = &hdev->asic_prop;
1379 	int rc;
1380 
1381 	hdev->mmu_priv.dr.mmu_pgt_pool =
1382 			gen_pool_create(__ffs(prop->dmmu.hop_table_size), -1);
1383 
1384 	if (!hdev->mmu_priv.dr.mmu_pgt_pool) {
1385 		dev_err(hdev->dev, "Failed to create page gen pool\n");
1386 		return -ENOMEM;
1387 	}
1388 
1389 	rc = gen_pool_add(hdev->mmu_priv.dr.mmu_pgt_pool, prop->mmu_pgt_addr +
1390 			prop->dmmu.hop0_tables_total_size,
1391 			prop->dmmu.pgt_size - prop->dmmu.hop0_tables_total_size,
1392 			-1);
1393 	if (rc) {
1394 		dev_err(hdev->dev, "Failed to add memory to page gen pool\n");
1395 		goto err_pool_add;
1396 	}
1397 
1398 	hdev->mmu_priv.dr.mmu_shadow_hop0 = kvcalloc(prop->max_asid,
1399 						prop->dmmu.hop_table_size, GFP_KERNEL);
1400 	if (ZERO_OR_NULL_PTR(hdev->mmu_priv.dr.mmu_shadow_hop0)) {
1401 		rc = -ENOMEM;
1402 		goto err_pool_add;
1403 	}
1404 
1405 	/* MMU H/W init will be done in device hw_init() */
1406 
1407 	return 0;
1408 
1409 err_pool_add:
1410 	gen_pool_destroy(hdev->mmu_priv.dr.mmu_pgt_pool);
1411 
1412 	return rc;
1413 }
1414 
1415 void hl_mmu_dr_fini(struct hl_device *hdev)
1416 {
1417 	/* MMU H/W fini was already done in device hw_fini() */
1418 
1419 	if (ZERO_OR_NULL_PTR(hdev->mmu_priv.dr.mmu_shadow_hop0))
1420 		return;
1421 
1422 	kvfree(hdev->mmu_priv.dr.mmu_shadow_hop0);
1423 	gen_pool_destroy(hdev->mmu_priv.dr.mmu_pgt_pool);
1424 
1425 	/* Make sure that if we arrive here again without init was
1426 	 * called we won't cause kernel panic. This can happen for
1427 	 * example if we fail during hard reset code at certain points
1428 	 */
1429 	hdev->mmu_priv.dr.mmu_shadow_hop0 = NULL;
1430 }
1431