1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * CPU-agnostic ARM page table allocator.
4  *
5  * Copyright (C) 2014 ARM Limited
6  *
7  * Author: Will Deacon <will.deacon@arm.com>
8  */
9 
10 #define pr_fmt(fmt)	"arm-lpae io-pgtable: " fmt
11 
12 #include <linux/atomic.h>
13 #include <linux/bitops.h>
14 #include <linux/io-pgtable.h>
15 #include <linux/kernel.h>
16 #include <linux/sizes.h>
17 #include <linux/slab.h>
18 #include <linux/types.h>
19 #include <linux/dma-mapping.h>
20 
21 #include <asm/barrier.h>
22 
23 #include "io-pgtable-arm.h"
24 
25 #define ARM_LPAE_MAX_ADDR_BITS		52
26 #define ARM_LPAE_S2_MAX_CONCAT_PAGES	16
27 #define ARM_LPAE_MAX_LEVELS		4
28 
29 /* Struct accessors */
30 #define io_pgtable_to_data(x)						\
31 	container_of((x), struct arm_lpae_io_pgtable, iop)
32 
33 #define io_pgtable_ops_to_data(x)					\
34 	io_pgtable_to_data(io_pgtable_ops_to_pgtable(x))
35 
36 /*
37  * Calculate the right shift amount to get to the portion describing level l
38  * in a virtual address mapped by the pagetable in d.
39  */
40 #define ARM_LPAE_LVL_SHIFT(l,d)						\
41 	(((ARM_LPAE_MAX_LEVELS - (l)) * (d)->bits_per_level) +		\
42 	ilog2(sizeof(arm_lpae_iopte)))
43 
44 #define ARM_LPAE_GRANULE(d)						\
45 	(sizeof(arm_lpae_iopte) << (d)->bits_per_level)
46 #define ARM_LPAE_PGD_SIZE(d)						\
47 	(sizeof(arm_lpae_iopte) << (d)->pgd_bits)
48 
49 #define ARM_LPAE_PTES_PER_TABLE(d)					\
50 	(ARM_LPAE_GRANULE(d) >> ilog2(sizeof(arm_lpae_iopte)))
51 
52 /*
53  * Calculate the index at level l used to map virtual address a using the
54  * pagetable in d.
55  */
56 #define ARM_LPAE_PGD_IDX(l,d)						\
57 	((l) == (d)->start_level ? (d)->pgd_bits - (d)->bits_per_level : 0)
58 
59 #define ARM_LPAE_LVL_IDX(a,l,d)						\
60 	(((u64)(a) >> ARM_LPAE_LVL_SHIFT(l,d)) &			\
61 	 ((1 << ((d)->bits_per_level + ARM_LPAE_PGD_IDX(l,d))) - 1))
62 
63 /* Calculate the block/page mapping size at level l for pagetable in d. */
64 #define ARM_LPAE_BLOCK_SIZE(l,d)	(1ULL << ARM_LPAE_LVL_SHIFT(l,d))
65 
66 /* Page table bits */
67 #define ARM_LPAE_PTE_TYPE_SHIFT		0
68 #define ARM_LPAE_PTE_TYPE_MASK		0x3
69 
70 #define ARM_LPAE_PTE_TYPE_BLOCK		1
71 #define ARM_LPAE_PTE_TYPE_TABLE		3
72 #define ARM_LPAE_PTE_TYPE_PAGE		3
73 
74 #define ARM_LPAE_PTE_ADDR_MASK		GENMASK_ULL(47,12)
75 
76 #define ARM_LPAE_PTE_NSTABLE		(((arm_lpae_iopte)1) << 63)
77 #define ARM_LPAE_PTE_XN			(((arm_lpae_iopte)3) << 53)
78 #define ARM_LPAE_PTE_AF			(((arm_lpae_iopte)1) << 10)
79 #define ARM_LPAE_PTE_SH_NS		(((arm_lpae_iopte)0) << 8)
80 #define ARM_LPAE_PTE_SH_OS		(((arm_lpae_iopte)2) << 8)
81 #define ARM_LPAE_PTE_SH_IS		(((arm_lpae_iopte)3) << 8)
82 #define ARM_LPAE_PTE_NS			(((arm_lpae_iopte)1) << 5)
83 #define ARM_LPAE_PTE_VALID		(((arm_lpae_iopte)1) << 0)
84 
85 #define ARM_LPAE_PTE_ATTR_LO_MASK	(((arm_lpae_iopte)0x3ff) << 2)
86 /* Ignore the contiguous bit for block splitting */
87 #define ARM_LPAE_PTE_ATTR_HI_MASK	(((arm_lpae_iopte)6) << 52)
88 #define ARM_LPAE_PTE_ATTR_MASK		(ARM_LPAE_PTE_ATTR_LO_MASK |	\
89 					 ARM_LPAE_PTE_ATTR_HI_MASK)
90 /* Software bit for solving coherency races */
91 #define ARM_LPAE_PTE_SW_SYNC		(((arm_lpae_iopte)1) << 55)
92 
93 /* Stage-1 PTE */
94 #define ARM_LPAE_PTE_AP_UNPRIV		(((arm_lpae_iopte)1) << 6)
95 #define ARM_LPAE_PTE_AP_RDONLY		(((arm_lpae_iopte)2) << 6)
96 #define ARM_LPAE_PTE_ATTRINDX_SHIFT	2
97 #define ARM_LPAE_PTE_nG			(((arm_lpae_iopte)1) << 11)
98 
99 /* Stage-2 PTE */
100 #define ARM_LPAE_PTE_HAP_FAULT		(((arm_lpae_iopte)0) << 6)
101 #define ARM_LPAE_PTE_HAP_READ		(((arm_lpae_iopte)1) << 6)
102 #define ARM_LPAE_PTE_HAP_WRITE		(((arm_lpae_iopte)2) << 6)
103 #define ARM_LPAE_PTE_MEMATTR_OIWB	(((arm_lpae_iopte)0xf) << 2)
104 #define ARM_LPAE_PTE_MEMATTR_NC		(((arm_lpae_iopte)0x5) << 2)
105 #define ARM_LPAE_PTE_MEMATTR_DEV	(((arm_lpae_iopte)0x1) << 2)
106 
107 /* Register bits */
108 #define ARM_LPAE_VTCR_SL0_MASK		0x3
109 
110 #define ARM_LPAE_TCR_T0SZ_SHIFT		0
111 
112 #define ARM_LPAE_VTCR_PS_SHIFT		16
113 #define ARM_LPAE_VTCR_PS_MASK		0x7
114 
115 #define ARM_LPAE_MAIR_ATTR_SHIFT(n)	((n) << 3)
116 #define ARM_LPAE_MAIR_ATTR_MASK		0xff
117 #define ARM_LPAE_MAIR_ATTR_DEVICE	0x04
118 #define ARM_LPAE_MAIR_ATTR_NC		0x44
119 #define ARM_LPAE_MAIR_ATTR_INC_OWBRWA	0xf4
120 #define ARM_LPAE_MAIR_ATTR_WBRWA	0xff
121 #define ARM_LPAE_MAIR_ATTR_IDX_NC	0
122 #define ARM_LPAE_MAIR_ATTR_IDX_CACHE	1
123 #define ARM_LPAE_MAIR_ATTR_IDX_DEV	2
124 #define ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE	3
125 
126 #define ARM_MALI_LPAE_TTBR_ADRMODE_TABLE (3u << 0)
127 #define ARM_MALI_LPAE_TTBR_READ_INNER	BIT(2)
128 #define ARM_MALI_LPAE_TTBR_SHARE_OUTER	BIT(4)
129 
130 #define ARM_MALI_LPAE_MEMATTR_IMP_DEF	0x88ULL
131 #define ARM_MALI_LPAE_MEMATTR_WRITE_ALLOC 0x8DULL
132 
133 /* IOPTE accessors */
134 #define iopte_deref(pte,d) __va(iopte_to_paddr(pte, d))
135 
136 #define iopte_type(pte)					\
137 	(((pte) >> ARM_LPAE_PTE_TYPE_SHIFT) & ARM_LPAE_PTE_TYPE_MASK)
138 
139 #define iopte_prot(pte)	((pte) & ARM_LPAE_PTE_ATTR_MASK)
140 
141 struct arm_lpae_io_pgtable {
142 	struct io_pgtable	iop;
143 
144 	int			pgd_bits;
145 	int			start_level;
146 	int			bits_per_level;
147 
148 	void			*pgd;
149 };
150 
151 typedef u64 arm_lpae_iopte;
152 
iopte_leaf(arm_lpae_iopte pte,int lvl,enum io_pgtable_fmt fmt)153 static inline bool iopte_leaf(arm_lpae_iopte pte, int lvl,
154 			      enum io_pgtable_fmt fmt)
155 {
156 	if (lvl == (ARM_LPAE_MAX_LEVELS - 1) && fmt != ARM_MALI_LPAE)
157 		return iopte_type(pte) == ARM_LPAE_PTE_TYPE_PAGE;
158 
159 	return iopte_type(pte) == ARM_LPAE_PTE_TYPE_BLOCK;
160 }
161 
paddr_to_iopte(phys_addr_t paddr,struct arm_lpae_io_pgtable * data)162 static arm_lpae_iopte paddr_to_iopte(phys_addr_t paddr,
163 				     struct arm_lpae_io_pgtable *data)
164 {
165 	arm_lpae_iopte pte = paddr;
166 
167 	/* Of the bits which overlap, either 51:48 or 15:12 are always RES0 */
168 	return (pte | (pte >> (48 - 12))) & ARM_LPAE_PTE_ADDR_MASK;
169 }
170 
iopte_to_paddr(arm_lpae_iopte pte,struct arm_lpae_io_pgtable * data)171 static phys_addr_t iopte_to_paddr(arm_lpae_iopte pte,
172 				  struct arm_lpae_io_pgtable *data)
173 {
174 	u64 paddr = pte & ARM_LPAE_PTE_ADDR_MASK;
175 
176 	if (ARM_LPAE_GRANULE(data) < SZ_64K)
177 		return paddr;
178 
179 	/* Rotate the packed high-order bits back to the top */
180 	return (paddr | (paddr << (48 - 12))) & (ARM_LPAE_PTE_ADDR_MASK << 4);
181 }
182 
183 static bool selftest_running = false;
184 
__arm_lpae_dma_addr(void * pages)185 static dma_addr_t __arm_lpae_dma_addr(void *pages)
186 {
187 	return (dma_addr_t)virt_to_phys(pages);
188 }
189 
__arm_lpae_alloc_pages(size_t size,gfp_t gfp,struct io_pgtable_cfg * cfg)190 static void *__arm_lpae_alloc_pages(size_t size, gfp_t gfp,
191 				    struct io_pgtable_cfg *cfg)
192 {
193 	struct device *dev = cfg->iommu_dev;
194 	int order = get_order(size);
195 	struct page *p;
196 	dma_addr_t dma;
197 	void *pages;
198 
199 	VM_BUG_ON((gfp & __GFP_HIGHMEM));
200 	p = alloc_pages_node(dev_to_node(dev), gfp | __GFP_ZERO, order);
201 	if (!p)
202 		return NULL;
203 
204 	pages = page_address(p);
205 	if (!cfg->coherent_walk) {
206 		dma = dma_map_single(dev, pages, size, DMA_TO_DEVICE);
207 		if (dma_mapping_error(dev, dma))
208 			goto out_free;
209 		/*
210 		 * We depend on the IOMMU being able to work with any physical
211 		 * address directly, so if the DMA layer suggests otherwise by
212 		 * translating or truncating them, that bodes very badly...
213 		 */
214 		if (dma != virt_to_phys(pages))
215 			goto out_unmap;
216 	}
217 
218 	return pages;
219 
220 out_unmap:
221 	dev_err(dev, "Cannot accommodate DMA translation for IOMMU page tables\n");
222 	dma_unmap_single(dev, dma, size, DMA_TO_DEVICE);
223 out_free:
224 	__free_pages(p, order);
225 	return NULL;
226 }
227 
__arm_lpae_free_pages(void * pages,size_t size,struct io_pgtable_cfg * cfg)228 static void __arm_lpae_free_pages(void *pages, size_t size,
229 				  struct io_pgtable_cfg *cfg)
230 {
231 	if (!cfg->coherent_walk)
232 		dma_unmap_single(cfg->iommu_dev, __arm_lpae_dma_addr(pages),
233 				 size, DMA_TO_DEVICE);
234 	free_pages((unsigned long)pages, get_order(size));
235 }
236 
__arm_lpae_sync_pte(arm_lpae_iopte * ptep,int num_entries,struct io_pgtable_cfg * cfg)237 static void __arm_lpae_sync_pte(arm_lpae_iopte *ptep, int num_entries,
238 				struct io_pgtable_cfg *cfg)
239 {
240 	dma_sync_single_for_device(cfg->iommu_dev, __arm_lpae_dma_addr(ptep),
241 				   sizeof(*ptep) * num_entries, DMA_TO_DEVICE);
242 }
243 
__arm_lpae_clear_pte(arm_lpae_iopte * ptep,struct io_pgtable_cfg * cfg)244 static void __arm_lpae_clear_pte(arm_lpae_iopte *ptep, struct io_pgtable_cfg *cfg)
245 {
246 
247 	*ptep = 0;
248 
249 	if (!cfg->coherent_walk)
250 		__arm_lpae_sync_pte(ptep, 1, cfg);
251 }
252 
253 static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
254 			       struct iommu_iotlb_gather *gather,
255 			       unsigned long iova, size_t size, size_t pgcount,
256 			       int lvl, arm_lpae_iopte *ptep);
257 
__arm_lpae_init_pte(struct arm_lpae_io_pgtable * data,phys_addr_t paddr,arm_lpae_iopte prot,int lvl,int num_entries,arm_lpae_iopte * ptep)258 static void __arm_lpae_init_pte(struct arm_lpae_io_pgtable *data,
259 				phys_addr_t paddr, arm_lpae_iopte prot,
260 				int lvl, int num_entries, arm_lpae_iopte *ptep)
261 {
262 	arm_lpae_iopte pte = prot;
263 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
264 	size_t sz = ARM_LPAE_BLOCK_SIZE(lvl, data);
265 	int i;
266 
267 	if (data->iop.fmt != ARM_MALI_LPAE && lvl == ARM_LPAE_MAX_LEVELS - 1)
268 		pte |= ARM_LPAE_PTE_TYPE_PAGE;
269 	else
270 		pte |= ARM_LPAE_PTE_TYPE_BLOCK;
271 
272 	for (i = 0; i < num_entries; i++)
273 		ptep[i] = pte | paddr_to_iopte(paddr + i * sz, data);
274 
275 	if (!cfg->coherent_walk)
276 		__arm_lpae_sync_pte(ptep, num_entries, cfg);
277 }
278 
arm_lpae_init_pte(struct arm_lpae_io_pgtable * data,unsigned long iova,phys_addr_t paddr,arm_lpae_iopte prot,int lvl,int num_entries,arm_lpae_iopte * ptep)279 static int arm_lpae_init_pte(struct arm_lpae_io_pgtable *data,
280 			     unsigned long iova, phys_addr_t paddr,
281 			     arm_lpae_iopte prot, int lvl, int num_entries,
282 			     arm_lpae_iopte *ptep)
283 {
284 	int i;
285 
286 	for (i = 0; i < num_entries; i++)
287 		if (iopte_leaf(ptep[i], lvl, data->iop.fmt)) {
288 			/* We require an unmap first */
289 			WARN_ON(!selftest_running);
290 			return -EEXIST;
291 		} else if (iopte_type(ptep[i]) == ARM_LPAE_PTE_TYPE_TABLE) {
292 			/*
293 			 * We need to unmap and free the old table before
294 			 * overwriting it with a block entry.
295 			 */
296 			arm_lpae_iopte *tblp;
297 			size_t sz = ARM_LPAE_BLOCK_SIZE(lvl, data);
298 
299 			tblp = ptep - ARM_LPAE_LVL_IDX(iova, lvl, data);
300 			if (__arm_lpae_unmap(data, NULL, iova + i * sz, sz, 1,
301 					     lvl, tblp) != sz) {
302 				WARN_ON(1);
303 				return -EINVAL;
304 			}
305 		}
306 
307 	__arm_lpae_init_pte(data, paddr, prot, lvl, num_entries, ptep);
308 	return 0;
309 }
310 
arm_lpae_install_table(arm_lpae_iopte * table,arm_lpae_iopte * ptep,arm_lpae_iopte curr,struct arm_lpae_io_pgtable * data)311 static arm_lpae_iopte arm_lpae_install_table(arm_lpae_iopte *table,
312 					     arm_lpae_iopte *ptep,
313 					     arm_lpae_iopte curr,
314 					     struct arm_lpae_io_pgtable *data)
315 {
316 	arm_lpae_iopte old, new;
317 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
318 
319 	new = paddr_to_iopte(__pa(table), data) | ARM_LPAE_PTE_TYPE_TABLE;
320 	if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS)
321 		new |= ARM_LPAE_PTE_NSTABLE;
322 
323 	/*
324 	 * Ensure the table itself is visible before its PTE can be.
325 	 * Whilst we could get away with cmpxchg64_release below, this
326 	 * doesn't have any ordering semantics when !CONFIG_SMP.
327 	 */
328 	dma_wmb();
329 
330 	old = cmpxchg64_relaxed(ptep, curr, new);
331 
332 	if (cfg->coherent_walk || (old & ARM_LPAE_PTE_SW_SYNC))
333 		return old;
334 
335 	/* Even if it's not ours, there's no point waiting; just kick it */
336 	__arm_lpae_sync_pte(ptep, 1, cfg);
337 	if (old == curr)
338 		WRITE_ONCE(*ptep, new | ARM_LPAE_PTE_SW_SYNC);
339 
340 	return old;
341 }
342 
__arm_lpae_map(struct arm_lpae_io_pgtable * data,unsigned long iova,phys_addr_t paddr,size_t size,size_t pgcount,arm_lpae_iopte prot,int lvl,arm_lpae_iopte * ptep,gfp_t gfp,size_t * mapped)343 static int __arm_lpae_map(struct arm_lpae_io_pgtable *data, unsigned long iova,
344 			  phys_addr_t paddr, size_t size, size_t pgcount,
345 			  arm_lpae_iopte prot, int lvl, arm_lpae_iopte *ptep,
346 			  gfp_t gfp, size_t *mapped)
347 {
348 	arm_lpae_iopte *cptep, pte;
349 	size_t block_size = ARM_LPAE_BLOCK_SIZE(lvl, data);
350 	size_t tblsz = ARM_LPAE_GRANULE(data);
351 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
352 	int ret = 0, num_entries, max_entries, map_idx_start;
353 
354 	/* Find our entry at the current level */
355 	map_idx_start = ARM_LPAE_LVL_IDX(iova, lvl, data);
356 	ptep += map_idx_start;
357 
358 	/* If we can install a leaf entry at this level, then do so */
359 	if (size == block_size) {
360 		max_entries = ARM_LPAE_PTES_PER_TABLE(data) - map_idx_start;
361 		num_entries = min_t(int, pgcount, max_entries);
362 		ret = arm_lpae_init_pte(data, iova, paddr, prot, lvl, num_entries, ptep);
363 		if (!ret)
364 			*mapped += num_entries * size;
365 
366 		return ret;
367 	}
368 
369 	/* We can't allocate tables at the final level */
370 	if (WARN_ON(lvl >= ARM_LPAE_MAX_LEVELS - 1))
371 		return -EINVAL;
372 
373 	/* Grab a pointer to the next level */
374 	pte = READ_ONCE(*ptep);
375 	if (!pte) {
376 		cptep = __arm_lpae_alloc_pages(tblsz, gfp, cfg);
377 		if (!cptep)
378 			return -ENOMEM;
379 
380 		pte = arm_lpae_install_table(cptep, ptep, 0, data);
381 		if (pte)
382 			__arm_lpae_free_pages(cptep, tblsz, cfg);
383 	} else if (!cfg->coherent_walk && !(pte & ARM_LPAE_PTE_SW_SYNC)) {
384 		__arm_lpae_sync_pte(ptep, 1, cfg);
385 	}
386 
387 	if (pte && !iopte_leaf(pte, lvl, data->iop.fmt)) {
388 		cptep = iopte_deref(pte, data);
389 	} else if (pte) {
390 		/* We require an unmap first */
391 		WARN_ON(!selftest_running);
392 		return -EEXIST;
393 	}
394 
395 	/* Rinse, repeat */
396 	return __arm_lpae_map(data, iova, paddr, size, pgcount, prot, lvl + 1,
397 			      cptep, gfp, mapped);
398 }
399 
arm_lpae_prot_to_pte(struct arm_lpae_io_pgtable * data,int prot)400 static arm_lpae_iopte arm_lpae_prot_to_pte(struct arm_lpae_io_pgtable *data,
401 					   int prot)
402 {
403 	arm_lpae_iopte pte;
404 
405 	if (data->iop.fmt == ARM_64_LPAE_S1 ||
406 	    data->iop.fmt == ARM_32_LPAE_S1) {
407 		pte = ARM_LPAE_PTE_nG;
408 		if (!(prot & IOMMU_WRITE) && (prot & IOMMU_READ))
409 			pte |= ARM_LPAE_PTE_AP_RDONLY;
410 		if (!(prot & IOMMU_PRIV))
411 			pte |= ARM_LPAE_PTE_AP_UNPRIV;
412 	} else {
413 		pte = ARM_LPAE_PTE_HAP_FAULT;
414 		if (prot & IOMMU_READ)
415 			pte |= ARM_LPAE_PTE_HAP_READ;
416 		if (prot & IOMMU_WRITE)
417 			pte |= ARM_LPAE_PTE_HAP_WRITE;
418 	}
419 
420 	/*
421 	 * Note that this logic is structured to accommodate Mali LPAE
422 	 * having stage-1-like attributes but stage-2-like permissions.
423 	 */
424 	if (data->iop.fmt == ARM_64_LPAE_S2 ||
425 	    data->iop.fmt == ARM_32_LPAE_S2) {
426 		if (prot & IOMMU_MMIO)
427 			pte |= ARM_LPAE_PTE_MEMATTR_DEV;
428 		else if (prot & IOMMU_CACHE)
429 			pte |= ARM_LPAE_PTE_MEMATTR_OIWB;
430 		else
431 			pte |= ARM_LPAE_PTE_MEMATTR_NC;
432 	} else {
433 		if (prot & IOMMU_MMIO)
434 			pte |= (ARM_LPAE_MAIR_ATTR_IDX_DEV
435 				<< ARM_LPAE_PTE_ATTRINDX_SHIFT);
436 		else if (prot & IOMMU_CACHE)
437 			pte |= (ARM_LPAE_MAIR_ATTR_IDX_CACHE
438 				<< ARM_LPAE_PTE_ATTRINDX_SHIFT);
439 	}
440 
441 	/*
442 	 * Also Mali has its own notions of shareability wherein its Inner
443 	 * domain covers the cores within the GPU, and its Outer domain is
444 	 * "outside the GPU" (i.e. either the Inner or System domain in CPU
445 	 * terms, depending on coherency).
446 	 */
447 	if (prot & IOMMU_CACHE && data->iop.fmt != ARM_MALI_LPAE)
448 		pte |= ARM_LPAE_PTE_SH_IS;
449 	else
450 		pte |= ARM_LPAE_PTE_SH_OS;
451 
452 	if (prot & IOMMU_NOEXEC)
453 		pte |= ARM_LPAE_PTE_XN;
454 
455 	if (data->iop.cfg.quirks & IO_PGTABLE_QUIRK_ARM_NS)
456 		pte |= ARM_LPAE_PTE_NS;
457 
458 	if (data->iop.fmt != ARM_MALI_LPAE)
459 		pte |= ARM_LPAE_PTE_AF;
460 
461 	return pte;
462 }
463 
arm_lpae_map_pages(struct io_pgtable_ops * ops,unsigned long iova,phys_addr_t paddr,size_t pgsize,size_t pgcount,int iommu_prot,gfp_t gfp,size_t * mapped)464 static int arm_lpae_map_pages(struct io_pgtable_ops *ops, unsigned long iova,
465 			      phys_addr_t paddr, size_t pgsize, size_t pgcount,
466 			      int iommu_prot, gfp_t gfp, size_t *mapped)
467 {
468 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
469 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
470 	arm_lpae_iopte *ptep = data->pgd;
471 	int ret, lvl = data->start_level;
472 	arm_lpae_iopte prot;
473 	long iaext = (s64)iova >> cfg->ias;
474 
475 	if (WARN_ON(!pgsize || (pgsize & cfg->pgsize_bitmap) != pgsize))
476 		return -EINVAL;
477 
478 	if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_TTBR1)
479 		iaext = ~iaext;
480 	if (WARN_ON(iaext || paddr >> cfg->oas))
481 		return -ERANGE;
482 
483 	/* If no access, then nothing to do */
484 	if (!(iommu_prot & (IOMMU_READ | IOMMU_WRITE)))
485 		return 0;
486 
487 	prot = arm_lpae_prot_to_pte(data, iommu_prot);
488 	ret = __arm_lpae_map(data, iova, paddr, pgsize, pgcount, prot, lvl,
489 			     ptep, gfp, mapped);
490 	/*
491 	 * Synchronise all PTE updates for the new mapping before there's
492 	 * a chance for anything to kick off a table walk for the new iova.
493 	 */
494 	wmb();
495 
496 	return ret;
497 }
498 
__arm_lpae_free_pgtable(struct arm_lpae_io_pgtable * data,int lvl,arm_lpae_iopte * ptep)499 static void __arm_lpae_free_pgtable(struct arm_lpae_io_pgtable *data, int lvl,
500 				    arm_lpae_iopte *ptep)
501 {
502 	arm_lpae_iopte *start, *end;
503 	unsigned long table_size;
504 
505 	if (lvl == data->start_level)
506 		table_size = ARM_LPAE_PGD_SIZE(data);
507 	else
508 		table_size = ARM_LPAE_GRANULE(data);
509 
510 	start = ptep;
511 
512 	/* Only leaf entries at the last level */
513 	if (lvl == ARM_LPAE_MAX_LEVELS - 1)
514 		end = ptep;
515 	else
516 		end = (void *)ptep + table_size;
517 
518 	while (ptep != end) {
519 		arm_lpae_iopte pte = *ptep++;
520 
521 		if (!pte || iopte_leaf(pte, lvl, data->iop.fmt))
522 			continue;
523 
524 		__arm_lpae_free_pgtable(data, lvl + 1, iopte_deref(pte, data));
525 	}
526 
527 	__arm_lpae_free_pages(start, table_size, &data->iop.cfg);
528 }
529 
arm_lpae_free_pgtable(struct io_pgtable * iop)530 static void arm_lpae_free_pgtable(struct io_pgtable *iop)
531 {
532 	struct arm_lpae_io_pgtable *data = io_pgtable_to_data(iop);
533 
534 	__arm_lpae_free_pgtable(data, data->start_level, data->pgd);
535 	kfree(data);
536 }
537 
arm_lpae_split_blk_unmap(struct arm_lpae_io_pgtable * data,struct iommu_iotlb_gather * gather,unsigned long iova,size_t size,arm_lpae_iopte blk_pte,int lvl,arm_lpae_iopte * ptep,size_t pgcount)538 static size_t arm_lpae_split_blk_unmap(struct arm_lpae_io_pgtable *data,
539 				       struct iommu_iotlb_gather *gather,
540 				       unsigned long iova, size_t size,
541 				       arm_lpae_iopte blk_pte, int lvl,
542 				       arm_lpae_iopte *ptep, size_t pgcount)
543 {
544 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
545 	arm_lpae_iopte pte, *tablep;
546 	phys_addr_t blk_paddr;
547 	size_t tablesz = ARM_LPAE_GRANULE(data);
548 	size_t split_sz = ARM_LPAE_BLOCK_SIZE(lvl, data);
549 	int ptes_per_table = ARM_LPAE_PTES_PER_TABLE(data);
550 	int i, unmap_idx_start = -1, num_entries = 0, max_entries;
551 
552 	if (WARN_ON(lvl == ARM_LPAE_MAX_LEVELS))
553 		return 0;
554 
555 	tablep = __arm_lpae_alloc_pages(tablesz, GFP_ATOMIC, cfg);
556 	if (!tablep)
557 		return 0; /* Bytes unmapped */
558 
559 	if (size == split_sz) {
560 		unmap_idx_start = ARM_LPAE_LVL_IDX(iova, lvl, data);
561 		max_entries = ptes_per_table - unmap_idx_start;
562 		num_entries = min_t(int, pgcount, max_entries);
563 	}
564 
565 	blk_paddr = iopte_to_paddr(blk_pte, data);
566 	pte = iopte_prot(blk_pte);
567 
568 	for (i = 0; i < ptes_per_table; i++, blk_paddr += split_sz) {
569 		/* Unmap! */
570 		if (i >= unmap_idx_start && i < (unmap_idx_start + num_entries))
571 			continue;
572 
573 		__arm_lpae_init_pte(data, blk_paddr, pte, lvl, 1, &tablep[i]);
574 	}
575 
576 	pte = arm_lpae_install_table(tablep, ptep, blk_pte, data);
577 	if (pte != blk_pte) {
578 		__arm_lpae_free_pages(tablep, tablesz, cfg);
579 		/*
580 		 * We may race against someone unmapping another part of this
581 		 * block, but anything else is invalid. We can't misinterpret
582 		 * a page entry here since we're never at the last level.
583 		 */
584 		if (iopte_type(pte) != ARM_LPAE_PTE_TYPE_TABLE)
585 			return 0;
586 
587 		tablep = iopte_deref(pte, data);
588 	} else if (unmap_idx_start >= 0) {
589 		for (i = 0; i < num_entries; i++)
590 			io_pgtable_tlb_add_page(&data->iop, gather, iova + i * size, size);
591 
592 		return num_entries * size;
593 	}
594 
595 	return __arm_lpae_unmap(data, gather, iova, size, pgcount, lvl, tablep);
596 }
597 
__arm_lpae_unmap(struct arm_lpae_io_pgtable * data,struct iommu_iotlb_gather * gather,unsigned long iova,size_t size,size_t pgcount,int lvl,arm_lpae_iopte * ptep)598 static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
599 			       struct iommu_iotlb_gather *gather,
600 			       unsigned long iova, size_t size, size_t pgcount,
601 			       int lvl, arm_lpae_iopte *ptep)
602 {
603 	arm_lpae_iopte pte;
604 	struct io_pgtable *iop = &data->iop;
605 	int i = 0, num_entries, max_entries, unmap_idx_start;
606 
607 	/* Something went horribly wrong and we ran out of page table */
608 	if (WARN_ON(lvl == ARM_LPAE_MAX_LEVELS))
609 		return 0;
610 
611 	unmap_idx_start = ARM_LPAE_LVL_IDX(iova, lvl, data);
612 	ptep += unmap_idx_start;
613 	pte = READ_ONCE(*ptep);
614 	if (WARN_ON(!pte))
615 		return 0;
616 
617 	/* If the size matches this level, we're in the right place */
618 	if (size == ARM_LPAE_BLOCK_SIZE(lvl, data)) {
619 		max_entries = ARM_LPAE_PTES_PER_TABLE(data) - unmap_idx_start;
620 		num_entries = min_t(int, pgcount, max_entries);
621 
622 		while (i < num_entries) {
623 			pte = READ_ONCE(*ptep);
624 			if (WARN_ON(!pte))
625 				break;
626 
627 			__arm_lpae_clear_pte(ptep, &iop->cfg);
628 
629 			if (!iopte_leaf(pte, lvl, iop->fmt)) {
630 				/* Also flush any partial walks */
631 				io_pgtable_tlb_flush_walk(iop, iova + i * size, size,
632 							  ARM_LPAE_GRANULE(data));
633 				__arm_lpae_free_pgtable(data, lvl + 1, iopte_deref(pte, data));
634 			} else if (!iommu_iotlb_gather_queued(gather)) {
635 				io_pgtable_tlb_add_page(iop, gather, iova + i * size, size);
636 			}
637 
638 			ptep++;
639 			i++;
640 		}
641 
642 		return i * size;
643 	} else if (iopte_leaf(pte, lvl, iop->fmt)) {
644 		/*
645 		 * Insert a table at the next level to map the old region,
646 		 * minus the part we want to unmap
647 		 */
648 		return arm_lpae_split_blk_unmap(data, gather, iova, size, pte,
649 						lvl + 1, ptep, pgcount);
650 	}
651 
652 	/* Keep on walkin' */
653 	ptep = iopte_deref(pte, data);
654 	return __arm_lpae_unmap(data, gather, iova, size, pgcount, lvl + 1, ptep);
655 }
656 
arm_lpae_unmap_pages(struct io_pgtable_ops * ops,unsigned long iova,size_t pgsize,size_t pgcount,struct iommu_iotlb_gather * gather)657 static size_t arm_lpae_unmap_pages(struct io_pgtable_ops *ops, unsigned long iova,
658 				   size_t pgsize, size_t pgcount,
659 				   struct iommu_iotlb_gather *gather)
660 {
661 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
662 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
663 	arm_lpae_iopte *ptep = data->pgd;
664 	long iaext = (s64)iova >> cfg->ias;
665 
666 	if (WARN_ON(!pgsize || (pgsize & cfg->pgsize_bitmap) != pgsize || !pgcount))
667 		return 0;
668 
669 	if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_TTBR1)
670 		iaext = ~iaext;
671 	if (WARN_ON(iaext))
672 		return 0;
673 
674 	return __arm_lpae_unmap(data, gather, iova, pgsize, pgcount,
675 				data->start_level, ptep);
676 }
677 
arm_lpae_iova_to_phys(struct io_pgtable_ops * ops,unsigned long iova)678 static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops,
679 					 unsigned long iova)
680 {
681 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
682 	arm_lpae_iopte pte, *ptep = data->pgd;
683 	int lvl = data->start_level;
684 
685 	do {
686 		/* Valid IOPTE pointer? */
687 		if (!ptep)
688 			return 0;
689 
690 		/* Grab the IOPTE we're interested in */
691 		ptep += ARM_LPAE_LVL_IDX(iova, lvl, data);
692 		pte = READ_ONCE(*ptep);
693 
694 		/* Valid entry? */
695 		if (!pte)
696 			return 0;
697 
698 		/* Leaf entry? */
699 		if (iopte_leaf(pte, lvl, data->iop.fmt))
700 			goto found_translation;
701 
702 		/* Take it to the next level */
703 		ptep = iopte_deref(pte, data);
704 	} while (++lvl < ARM_LPAE_MAX_LEVELS);
705 
706 	/* Ran out of page tables to walk */
707 	return 0;
708 
709 found_translation:
710 	iova &= (ARM_LPAE_BLOCK_SIZE(lvl, data) - 1);
711 	return iopte_to_paddr(pte, data) | iova;
712 }
713 
arm_lpae_restrict_pgsizes(struct io_pgtable_cfg * cfg)714 static void arm_lpae_restrict_pgsizes(struct io_pgtable_cfg *cfg)
715 {
716 	unsigned long granule, page_sizes;
717 	unsigned int max_addr_bits = 48;
718 
719 	/*
720 	 * We need to restrict the supported page sizes to match the
721 	 * translation regime for a particular granule. Aim to match
722 	 * the CPU page size if possible, otherwise prefer smaller sizes.
723 	 * While we're at it, restrict the block sizes to match the
724 	 * chosen granule.
725 	 */
726 	if (cfg->pgsize_bitmap & PAGE_SIZE)
727 		granule = PAGE_SIZE;
728 	else if (cfg->pgsize_bitmap & ~PAGE_MASK)
729 		granule = 1UL << __fls(cfg->pgsize_bitmap & ~PAGE_MASK);
730 	else if (cfg->pgsize_bitmap & PAGE_MASK)
731 		granule = 1UL << __ffs(cfg->pgsize_bitmap & PAGE_MASK);
732 	else
733 		granule = 0;
734 
735 	switch (granule) {
736 	case SZ_4K:
737 		page_sizes = (SZ_4K | SZ_2M | SZ_1G);
738 		break;
739 	case SZ_16K:
740 		page_sizes = (SZ_16K | SZ_32M);
741 		break;
742 	case SZ_64K:
743 		max_addr_bits = 52;
744 		page_sizes = (SZ_64K | SZ_512M);
745 		if (cfg->oas > 48)
746 			page_sizes |= 1ULL << 42; /* 4TB */
747 		break;
748 	default:
749 		page_sizes = 0;
750 	}
751 
752 	cfg->pgsize_bitmap &= page_sizes;
753 	cfg->ias = min(cfg->ias, max_addr_bits);
754 	cfg->oas = min(cfg->oas, max_addr_bits);
755 }
756 
757 static struct arm_lpae_io_pgtable *
arm_lpae_alloc_pgtable(struct io_pgtable_cfg * cfg)758 arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg)
759 {
760 	struct arm_lpae_io_pgtable *data;
761 	int levels, va_bits, pg_shift;
762 
763 	arm_lpae_restrict_pgsizes(cfg);
764 
765 	if (!(cfg->pgsize_bitmap & (SZ_4K | SZ_16K | SZ_64K)))
766 		return NULL;
767 
768 	if (cfg->ias > ARM_LPAE_MAX_ADDR_BITS)
769 		return NULL;
770 
771 	if (cfg->oas > ARM_LPAE_MAX_ADDR_BITS)
772 		return NULL;
773 
774 	data = kmalloc(sizeof(*data), GFP_KERNEL);
775 	if (!data)
776 		return NULL;
777 
778 	pg_shift = __ffs(cfg->pgsize_bitmap);
779 	data->bits_per_level = pg_shift - ilog2(sizeof(arm_lpae_iopte));
780 
781 	va_bits = cfg->ias - pg_shift;
782 	levels = DIV_ROUND_UP(va_bits, data->bits_per_level);
783 	data->start_level = ARM_LPAE_MAX_LEVELS - levels;
784 
785 	/* Calculate the actual size of our pgd (without concatenation) */
786 	data->pgd_bits = va_bits - (data->bits_per_level * (levels - 1));
787 
788 	data->iop.ops = (struct io_pgtable_ops) {
789 		.map_pages	= arm_lpae_map_pages,
790 		.unmap_pages	= arm_lpae_unmap_pages,
791 		.iova_to_phys	= arm_lpae_iova_to_phys,
792 	};
793 
794 	return data;
795 }
796 
797 static struct io_pgtable *
arm_64_lpae_alloc_pgtable_s1(struct io_pgtable_cfg * cfg,void * cookie)798 arm_64_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie)
799 {
800 	u64 reg;
801 	struct arm_lpae_io_pgtable *data;
802 	typeof(&cfg->arm_lpae_s1_cfg.tcr) tcr = &cfg->arm_lpae_s1_cfg.tcr;
803 	bool tg1;
804 
805 	if (cfg->quirks & ~(IO_PGTABLE_QUIRK_ARM_NS |
806 			    IO_PGTABLE_QUIRK_ARM_TTBR1 |
807 			    IO_PGTABLE_QUIRK_ARM_OUTER_WBWA))
808 		return NULL;
809 
810 	data = arm_lpae_alloc_pgtable(cfg);
811 	if (!data)
812 		return NULL;
813 
814 	/* TCR */
815 	if (cfg->coherent_walk) {
816 		tcr->sh = ARM_LPAE_TCR_SH_IS;
817 		tcr->irgn = ARM_LPAE_TCR_RGN_WBWA;
818 		tcr->orgn = ARM_LPAE_TCR_RGN_WBWA;
819 		if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_OUTER_WBWA)
820 			goto out_free_data;
821 	} else {
822 		tcr->sh = ARM_LPAE_TCR_SH_OS;
823 		tcr->irgn = ARM_LPAE_TCR_RGN_NC;
824 		if (!(cfg->quirks & IO_PGTABLE_QUIRK_ARM_OUTER_WBWA))
825 			tcr->orgn = ARM_LPAE_TCR_RGN_NC;
826 		else
827 			tcr->orgn = ARM_LPAE_TCR_RGN_WBWA;
828 	}
829 
830 	tg1 = cfg->quirks & IO_PGTABLE_QUIRK_ARM_TTBR1;
831 	switch (ARM_LPAE_GRANULE(data)) {
832 	case SZ_4K:
833 		tcr->tg = tg1 ? ARM_LPAE_TCR_TG1_4K : ARM_LPAE_TCR_TG0_4K;
834 		break;
835 	case SZ_16K:
836 		tcr->tg = tg1 ? ARM_LPAE_TCR_TG1_16K : ARM_LPAE_TCR_TG0_16K;
837 		break;
838 	case SZ_64K:
839 		tcr->tg = tg1 ? ARM_LPAE_TCR_TG1_64K : ARM_LPAE_TCR_TG0_64K;
840 		break;
841 	}
842 
843 	switch (cfg->oas) {
844 	case 32:
845 		tcr->ips = ARM_LPAE_TCR_PS_32_BIT;
846 		break;
847 	case 36:
848 		tcr->ips = ARM_LPAE_TCR_PS_36_BIT;
849 		break;
850 	case 40:
851 		tcr->ips = ARM_LPAE_TCR_PS_40_BIT;
852 		break;
853 	case 42:
854 		tcr->ips = ARM_LPAE_TCR_PS_42_BIT;
855 		break;
856 	case 44:
857 		tcr->ips = ARM_LPAE_TCR_PS_44_BIT;
858 		break;
859 	case 48:
860 		tcr->ips = ARM_LPAE_TCR_PS_48_BIT;
861 		break;
862 	case 52:
863 		tcr->ips = ARM_LPAE_TCR_PS_52_BIT;
864 		break;
865 	default:
866 		goto out_free_data;
867 	}
868 
869 	tcr->tsz = 64ULL - cfg->ias;
870 
871 	/* MAIRs */
872 	reg = (ARM_LPAE_MAIR_ATTR_NC
873 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_NC)) |
874 	      (ARM_LPAE_MAIR_ATTR_WBRWA
875 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_CACHE)) |
876 	      (ARM_LPAE_MAIR_ATTR_DEVICE
877 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_DEV)) |
878 	      (ARM_LPAE_MAIR_ATTR_INC_OWBRWA
879 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE));
880 
881 	cfg->arm_lpae_s1_cfg.mair = reg;
882 
883 	/* Looking good; allocate a pgd */
884 	data->pgd = __arm_lpae_alloc_pages(ARM_LPAE_PGD_SIZE(data),
885 					   GFP_KERNEL, cfg);
886 	if (!data->pgd)
887 		goto out_free_data;
888 
889 	/* Ensure the empty pgd is visible before any actual TTBR write */
890 	wmb();
891 
892 	/* TTBR */
893 	cfg->arm_lpae_s1_cfg.ttbr = virt_to_phys(data->pgd);
894 	return &data->iop;
895 
896 out_free_data:
897 	kfree(data);
898 	return NULL;
899 }
900 
901 static struct io_pgtable *
arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg * cfg,void * cookie)902 arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
903 {
904 	u64 sl;
905 	struct arm_lpae_io_pgtable *data;
906 	typeof(&cfg->arm_lpae_s2_cfg.vtcr) vtcr = &cfg->arm_lpae_s2_cfg.vtcr;
907 
908 	/* The NS quirk doesn't apply at stage 2 */
909 	if (cfg->quirks)
910 		return NULL;
911 
912 	data = arm_lpae_alloc_pgtable(cfg);
913 	if (!data)
914 		return NULL;
915 
916 	/*
917 	 * Concatenate PGDs at level 1 if possible in order to reduce
918 	 * the depth of the stage-2 walk.
919 	 */
920 	if (data->start_level == 0) {
921 		unsigned long pgd_pages;
922 
923 		pgd_pages = ARM_LPAE_PGD_SIZE(data) / sizeof(arm_lpae_iopte);
924 		if (pgd_pages <= ARM_LPAE_S2_MAX_CONCAT_PAGES) {
925 			data->pgd_bits += data->bits_per_level;
926 			data->start_level++;
927 		}
928 	}
929 
930 	/* VTCR */
931 	if (cfg->coherent_walk) {
932 		vtcr->sh = ARM_LPAE_TCR_SH_IS;
933 		vtcr->irgn = ARM_LPAE_TCR_RGN_WBWA;
934 		vtcr->orgn = ARM_LPAE_TCR_RGN_WBWA;
935 	} else {
936 		vtcr->sh = ARM_LPAE_TCR_SH_OS;
937 		vtcr->irgn = ARM_LPAE_TCR_RGN_NC;
938 		vtcr->orgn = ARM_LPAE_TCR_RGN_NC;
939 	}
940 
941 	sl = data->start_level;
942 
943 	switch (ARM_LPAE_GRANULE(data)) {
944 	case SZ_4K:
945 		vtcr->tg = ARM_LPAE_TCR_TG0_4K;
946 		sl++; /* SL0 format is different for 4K granule size */
947 		break;
948 	case SZ_16K:
949 		vtcr->tg = ARM_LPAE_TCR_TG0_16K;
950 		break;
951 	case SZ_64K:
952 		vtcr->tg = ARM_LPAE_TCR_TG0_64K;
953 		break;
954 	}
955 
956 	switch (cfg->oas) {
957 	case 32:
958 		vtcr->ps = ARM_LPAE_TCR_PS_32_BIT;
959 		break;
960 	case 36:
961 		vtcr->ps = ARM_LPAE_TCR_PS_36_BIT;
962 		break;
963 	case 40:
964 		vtcr->ps = ARM_LPAE_TCR_PS_40_BIT;
965 		break;
966 	case 42:
967 		vtcr->ps = ARM_LPAE_TCR_PS_42_BIT;
968 		break;
969 	case 44:
970 		vtcr->ps = ARM_LPAE_TCR_PS_44_BIT;
971 		break;
972 	case 48:
973 		vtcr->ps = ARM_LPAE_TCR_PS_48_BIT;
974 		break;
975 	case 52:
976 		vtcr->ps = ARM_LPAE_TCR_PS_52_BIT;
977 		break;
978 	default:
979 		goto out_free_data;
980 	}
981 
982 	vtcr->tsz = 64ULL - cfg->ias;
983 	vtcr->sl = ~sl & ARM_LPAE_VTCR_SL0_MASK;
984 
985 	/* Allocate pgd pages */
986 	data->pgd = __arm_lpae_alloc_pages(ARM_LPAE_PGD_SIZE(data),
987 					   GFP_KERNEL, cfg);
988 	if (!data->pgd)
989 		goto out_free_data;
990 
991 	/* Ensure the empty pgd is visible before any actual TTBR write */
992 	wmb();
993 
994 	/* VTTBR */
995 	cfg->arm_lpae_s2_cfg.vttbr = virt_to_phys(data->pgd);
996 	return &data->iop;
997 
998 out_free_data:
999 	kfree(data);
1000 	return NULL;
1001 }
1002 
1003 static struct io_pgtable *
arm_32_lpae_alloc_pgtable_s1(struct io_pgtable_cfg * cfg,void * cookie)1004 arm_32_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie)
1005 {
1006 	if (cfg->ias > 32 || cfg->oas > 40)
1007 		return NULL;
1008 
1009 	cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
1010 	return arm_64_lpae_alloc_pgtable_s1(cfg, cookie);
1011 }
1012 
1013 static struct io_pgtable *
arm_32_lpae_alloc_pgtable_s2(struct io_pgtable_cfg * cfg,void * cookie)1014 arm_32_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
1015 {
1016 	if (cfg->ias > 40 || cfg->oas > 40)
1017 		return NULL;
1018 
1019 	cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
1020 	return arm_64_lpae_alloc_pgtable_s2(cfg, cookie);
1021 }
1022 
1023 static struct io_pgtable *
arm_mali_lpae_alloc_pgtable(struct io_pgtable_cfg * cfg,void * cookie)1024 arm_mali_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)
1025 {
1026 	struct arm_lpae_io_pgtable *data;
1027 
1028 	/* No quirks for Mali (hopefully) */
1029 	if (cfg->quirks)
1030 		return NULL;
1031 
1032 	if (cfg->ias > 48 || cfg->oas > 40)
1033 		return NULL;
1034 
1035 	cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
1036 
1037 	data = arm_lpae_alloc_pgtable(cfg);
1038 	if (!data)
1039 		return NULL;
1040 
1041 	/* Mali seems to need a full 4-level table regardless of IAS */
1042 	if (data->start_level > 0) {
1043 		data->start_level = 0;
1044 		data->pgd_bits = 0;
1045 	}
1046 	/*
1047 	 * MEMATTR: Mali has no actual notion of a non-cacheable type, so the
1048 	 * best we can do is mimic the out-of-tree driver and hope that the
1049 	 * "implementation-defined caching policy" is good enough. Similarly,
1050 	 * we'll use it for the sake of a valid attribute for our 'device'
1051 	 * index, although callers should never request that in practice.
1052 	 */
1053 	cfg->arm_mali_lpae_cfg.memattr =
1054 		(ARM_MALI_LPAE_MEMATTR_IMP_DEF
1055 		 << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_NC)) |
1056 		(ARM_MALI_LPAE_MEMATTR_WRITE_ALLOC
1057 		 << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_CACHE)) |
1058 		(ARM_MALI_LPAE_MEMATTR_IMP_DEF
1059 		 << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_DEV));
1060 
1061 	data->pgd = __arm_lpae_alloc_pages(ARM_LPAE_PGD_SIZE(data), GFP_KERNEL,
1062 					   cfg);
1063 	if (!data->pgd)
1064 		goto out_free_data;
1065 
1066 	/* Ensure the empty pgd is visible before TRANSTAB can be written */
1067 	wmb();
1068 
1069 	cfg->arm_mali_lpae_cfg.transtab = virt_to_phys(data->pgd) |
1070 					  ARM_MALI_LPAE_TTBR_READ_INNER |
1071 					  ARM_MALI_LPAE_TTBR_ADRMODE_TABLE;
1072 	if (cfg->coherent_walk)
1073 		cfg->arm_mali_lpae_cfg.transtab |= ARM_MALI_LPAE_TTBR_SHARE_OUTER;
1074 
1075 	return &data->iop;
1076 
1077 out_free_data:
1078 	kfree(data);
1079 	return NULL;
1080 }
1081 
1082 struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns = {
1083 	.alloc	= arm_64_lpae_alloc_pgtable_s1,
1084 	.free	= arm_lpae_free_pgtable,
1085 };
1086 
1087 struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns = {
1088 	.alloc	= arm_64_lpae_alloc_pgtable_s2,
1089 	.free	= arm_lpae_free_pgtable,
1090 };
1091 
1092 struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns = {
1093 	.alloc	= arm_32_lpae_alloc_pgtable_s1,
1094 	.free	= arm_lpae_free_pgtable,
1095 };
1096 
1097 struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns = {
1098 	.alloc	= arm_32_lpae_alloc_pgtable_s2,
1099 	.free	= arm_lpae_free_pgtable,
1100 };
1101 
1102 struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns = {
1103 	.alloc	= arm_mali_lpae_alloc_pgtable,
1104 	.free	= arm_lpae_free_pgtable,
1105 };
1106 
1107 #ifdef CONFIG_IOMMU_IO_PGTABLE_LPAE_SELFTEST
1108 
1109 static struct io_pgtable_cfg *cfg_cookie __initdata;
1110 
dummy_tlb_flush_all(void * cookie)1111 static void __init dummy_tlb_flush_all(void *cookie)
1112 {
1113 	WARN_ON(cookie != cfg_cookie);
1114 }
1115 
dummy_tlb_flush(unsigned long iova,size_t size,size_t granule,void * cookie)1116 static void __init dummy_tlb_flush(unsigned long iova, size_t size,
1117 				   size_t granule, void *cookie)
1118 {
1119 	WARN_ON(cookie != cfg_cookie);
1120 	WARN_ON(!(size & cfg_cookie->pgsize_bitmap));
1121 }
1122 
dummy_tlb_add_page(struct iommu_iotlb_gather * gather,unsigned long iova,size_t granule,void * cookie)1123 static void __init dummy_tlb_add_page(struct iommu_iotlb_gather *gather,
1124 				      unsigned long iova, size_t granule,
1125 				      void *cookie)
1126 {
1127 	dummy_tlb_flush(iova, granule, granule, cookie);
1128 }
1129 
1130 static const struct iommu_flush_ops dummy_tlb_ops __initconst = {
1131 	.tlb_flush_all	= dummy_tlb_flush_all,
1132 	.tlb_flush_walk	= dummy_tlb_flush,
1133 	.tlb_add_page	= dummy_tlb_add_page,
1134 };
1135 
arm_lpae_dump_ops(struct io_pgtable_ops * ops)1136 static void __init arm_lpae_dump_ops(struct io_pgtable_ops *ops)
1137 {
1138 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
1139 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
1140 
1141 	pr_err("cfg: pgsize_bitmap 0x%lx, ias %u-bit\n",
1142 		cfg->pgsize_bitmap, cfg->ias);
1143 	pr_err("data: %d levels, 0x%zx pgd_size, %u pg_shift, %u bits_per_level, pgd @ %p\n",
1144 		ARM_LPAE_MAX_LEVELS - data->start_level, ARM_LPAE_PGD_SIZE(data),
1145 		ilog2(ARM_LPAE_GRANULE(data)), data->bits_per_level, data->pgd);
1146 }
1147 
1148 #define __FAIL(ops, i)	({						\
1149 		WARN(1, "selftest: test failed for fmt idx %d\n", (i));	\
1150 		arm_lpae_dump_ops(ops);					\
1151 		selftest_running = false;				\
1152 		-EFAULT;						\
1153 })
1154 
arm_lpae_run_tests(struct io_pgtable_cfg * cfg)1155 static int __init arm_lpae_run_tests(struct io_pgtable_cfg *cfg)
1156 {
1157 	static const enum io_pgtable_fmt fmts[] __initconst = {
1158 		ARM_64_LPAE_S1,
1159 		ARM_64_LPAE_S2,
1160 	};
1161 
1162 	int i, j;
1163 	unsigned long iova;
1164 	size_t size, mapped;
1165 	struct io_pgtable_ops *ops;
1166 
1167 	selftest_running = true;
1168 
1169 	for (i = 0; i < ARRAY_SIZE(fmts); ++i) {
1170 		cfg_cookie = cfg;
1171 		ops = alloc_io_pgtable_ops(fmts[i], cfg, cfg);
1172 		if (!ops) {
1173 			pr_err("selftest: failed to allocate io pgtable ops\n");
1174 			return -ENOMEM;
1175 		}
1176 
1177 		/*
1178 		 * Initial sanity checks.
1179 		 * Empty page tables shouldn't provide any translations.
1180 		 */
1181 		if (ops->iova_to_phys(ops, 42))
1182 			return __FAIL(ops, i);
1183 
1184 		if (ops->iova_to_phys(ops, SZ_1G + 42))
1185 			return __FAIL(ops, i);
1186 
1187 		if (ops->iova_to_phys(ops, SZ_2G + 42))
1188 			return __FAIL(ops, i);
1189 
1190 		/*
1191 		 * Distinct mappings of different granule sizes.
1192 		 */
1193 		iova = 0;
1194 		for_each_set_bit(j, &cfg->pgsize_bitmap, BITS_PER_LONG) {
1195 			size = 1UL << j;
1196 
1197 			if (ops->map_pages(ops, iova, iova, size, 1,
1198 					   IOMMU_READ | IOMMU_WRITE |
1199 					   IOMMU_NOEXEC | IOMMU_CACHE,
1200 					   GFP_KERNEL, &mapped))
1201 				return __FAIL(ops, i);
1202 
1203 			/* Overlapping mappings */
1204 			if (!ops->map_pages(ops, iova, iova + size, size, 1,
1205 					    IOMMU_READ | IOMMU_NOEXEC,
1206 					    GFP_KERNEL, &mapped))
1207 				return __FAIL(ops, i);
1208 
1209 			if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
1210 				return __FAIL(ops, i);
1211 
1212 			iova += SZ_1G;
1213 		}
1214 
1215 		/* Partial unmap */
1216 		size = 1UL << __ffs(cfg->pgsize_bitmap);
1217 		if (ops->unmap_pages(ops, SZ_1G + size, size, 1, NULL) != size)
1218 			return __FAIL(ops, i);
1219 
1220 		/* Remap of partial unmap */
1221 		if (ops->map_pages(ops, SZ_1G + size, size, size, 1,
1222 				   IOMMU_READ, GFP_KERNEL, &mapped))
1223 			return __FAIL(ops, i);
1224 
1225 		if (ops->iova_to_phys(ops, SZ_1G + size + 42) != (size + 42))
1226 			return __FAIL(ops, i);
1227 
1228 		/* Full unmap */
1229 		iova = 0;
1230 		for_each_set_bit(j, &cfg->pgsize_bitmap, BITS_PER_LONG) {
1231 			size = 1UL << j;
1232 
1233 			if (ops->unmap_pages(ops, iova, size, 1, NULL) != size)
1234 				return __FAIL(ops, i);
1235 
1236 			if (ops->iova_to_phys(ops, iova + 42))
1237 				return __FAIL(ops, i);
1238 
1239 			/* Remap full block */
1240 			if (ops->map_pages(ops, iova, iova, size, 1,
1241 					   IOMMU_WRITE, GFP_KERNEL, &mapped))
1242 				return __FAIL(ops, i);
1243 
1244 			if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
1245 				return __FAIL(ops, i);
1246 
1247 			iova += SZ_1G;
1248 		}
1249 
1250 		free_io_pgtable_ops(ops);
1251 	}
1252 
1253 	selftest_running = false;
1254 	return 0;
1255 }
1256 
arm_lpae_do_selftests(void)1257 static int __init arm_lpae_do_selftests(void)
1258 {
1259 	static const unsigned long pgsize[] __initconst = {
1260 		SZ_4K | SZ_2M | SZ_1G,
1261 		SZ_16K | SZ_32M,
1262 		SZ_64K | SZ_512M,
1263 	};
1264 
1265 	static const unsigned int ias[] __initconst = {
1266 		32, 36, 40, 42, 44, 48,
1267 	};
1268 
1269 	int i, j, pass = 0, fail = 0;
1270 	struct device dev;
1271 	struct io_pgtable_cfg cfg = {
1272 		.tlb = &dummy_tlb_ops,
1273 		.oas = 48,
1274 		.coherent_walk = true,
1275 		.iommu_dev = &dev,
1276 	};
1277 
1278 	/* __arm_lpae_alloc_pages() merely needs dev_to_node() to work */
1279 	set_dev_node(&dev, NUMA_NO_NODE);
1280 
1281 	for (i = 0; i < ARRAY_SIZE(pgsize); ++i) {
1282 		for (j = 0; j < ARRAY_SIZE(ias); ++j) {
1283 			cfg.pgsize_bitmap = pgsize[i];
1284 			cfg.ias = ias[j];
1285 			pr_info("selftest: pgsize_bitmap 0x%08lx, IAS %u\n",
1286 				pgsize[i], ias[j]);
1287 			if (arm_lpae_run_tests(&cfg))
1288 				fail++;
1289 			else
1290 				pass++;
1291 		}
1292 	}
1293 
1294 	pr_info("selftest: completed with %d PASS %d FAIL\n", pass, fail);
1295 	return fail ? -EFAULT : 0;
1296 }
1297 subsys_initcall(arm_lpae_do_selftests);
1298 #endif
1299