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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_INC_OWBRANWA		0xe4ULL
122 #define ARM_LPAE_MAIR_ATTR_IWBRWA_OWBRANWA	0xefULL
123 #define ARM_LPAE_MAIR_ATTR_IDX_NC	0
124 #define ARM_LPAE_MAIR_ATTR_IDX_CACHE	1
125 #define ARM_LPAE_MAIR_ATTR_IDX_DEV	2
126 #define ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE	3
127 #define ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE_NWA		4
128 #define ARM_LPAE_MAIR_ATTR_IDX_ICACHE_OCACHE_NWA	5
129 
130 #define ARM_MALI_LPAE_TTBR_ADRMODE_TABLE (3u << 0)
131 #define ARM_MALI_LPAE_TTBR_READ_INNER	BIT(2)
132 #define ARM_MALI_LPAE_TTBR_SHARE_OUTER	BIT(4)
133 
134 #define ARM_MALI_LPAE_MEMATTR_IMP_DEF	0x88ULL
135 #define ARM_MALI_LPAE_MEMATTR_WRITE_ALLOC 0x8DULL
136 
137 #define APPLE_DART_PTE_PROT_NO_WRITE (1<<7)
138 #define APPLE_DART_PTE_PROT_NO_READ (1<<8)
139 
140 /* IOPTE accessors */
141 #define iopte_deref(pte,d) __va(iopte_to_paddr(pte, d))
142 
143 #define iopte_type(pte)					\
144 	(((pte) >> ARM_LPAE_PTE_TYPE_SHIFT) & ARM_LPAE_PTE_TYPE_MASK)
145 
146 #define iopte_prot(pte)	((pte) & ARM_LPAE_PTE_ATTR_MASK)
147 
148 struct arm_lpae_io_pgtable {
149 	struct io_pgtable	iop;
150 
151 	int			pgd_bits;
152 	int			start_level;
153 	int			bits_per_level;
154 
155 	void			*pgd;
156 };
157 
158 typedef u64 arm_lpae_iopte;
159 
iopte_leaf(arm_lpae_iopte pte,int lvl,enum io_pgtable_fmt fmt)160 static inline bool iopte_leaf(arm_lpae_iopte pte, int lvl,
161 			      enum io_pgtable_fmt fmt)
162 {
163 	if (lvl == (ARM_LPAE_MAX_LEVELS - 1) && fmt != ARM_MALI_LPAE)
164 		return iopte_type(pte) == ARM_LPAE_PTE_TYPE_PAGE;
165 
166 	return iopte_type(pte) == ARM_LPAE_PTE_TYPE_BLOCK;
167 }
168 
paddr_to_iopte(phys_addr_t paddr,struct arm_lpae_io_pgtable * data)169 static arm_lpae_iopte paddr_to_iopte(phys_addr_t paddr,
170 				     struct arm_lpae_io_pgtable *data)
171 {
172 	arm_lpae_iopte pte = paddr;
173 
174 	/* Of the bits which overlap, either 51:48 or 15:12 are always RES0 */
175 	return (pte | (pte >> (48 - 12))) & ARM_LPAE_PTE_ADDR_MASK;
176 }
177 
iopte_to_paddr(arm_lpae_iopte pte,struct arm_lpae_io_pgtable * data)178 static phys_addr_t iopte_to_paddr(arm_lpae_iopte pte,
179 				  struct arm_lpae_io_pgtable *data)
180 {
181 	u64 paddr = pte & ARM_LPAE_PTE_ADDR_MASK;
182 
183 	if (ARM_LPAE_GRANULE(data) < SZ_64K)
184 		return paddr;
185 
186 	/* Rotate the packed high-order bits back to the top */
187 	return (paddr | (paddr << (48 - 12))) & (ARM_LPAE_PTE_ADDR_MASK << 4);
188 }
189 
190 static bool selftest_running = false;
191 
__arm_lpae_dma_addr(void * pages)192 static dma_addr_t __arm_lpae_dma_addr(void *pages)
193 {
194 	return (dma_addr_t)virt_to_phys(pages);
195 }
196 
__arm_lpae_alloc_pages(size_t size,gfp_t gfp,struct io_pgtable_cfg * cfg)197 static void *__arm_lpae_alloc_pages(size_t size, gfp_t gfp,
198 				    struct io_pgtable_cfg *cfg)
199 {
200 	struct device *dev = cfg->iommu_dev;
201 	int order = get_order(size);
202 	struct page *p;
203 	dma_addr_t dma;
204 	void *pages;
205 
206 	VM_BUG_ON((gfp & __GFP_HIGHMEM));
207 	p = alloc_pages_node(dev ? dev_to_node(dev) : NUMA_NO_NODE,
208 			     gfp | __GFP_ZERO, order);
209 	if (!p)
210 		return NULL;
211 
212 	pages = page_address(p);
213 	if (!cfg->coherent_walk) {
214 		dma = dma_map_single(dev, pages, size, DMA_TO_DEVICE);
215 		if (dma_mapping_error(dev, dma))
216 			goto out_free;
217 		/*
218 		 * We depend on the IOMMU being able to work with any physical
219 		 * address directly, so if the DMA layer suggests otherwise by
220 		 * translating or truncating them, that bodes very badly...
221 		 */
222 		if (dma != virt_to_phys(pages))
223 			goto out_unmap;
224 	}
225 
226 	return pages;
227 
228 out_unmap:
229 	dev_err(dev, "Cannot accommodate DMA translation for IOMMU page tables\n");
230 	dma_unmap_single(dev, dma, size, DMA_TO_DEVICE);
231 out_free:
232 	__free_pages(p, order);
233 	return NULL;
234 }
235 
__arm_lpae_free_pages(void * pages,size_t size,struct io_pgtable_cfg * cfg)236 static void __arm_lpae_free_pages(void *pages, size_t size,
237 				  struct io_pgtable_cfg *cfg)
238 {
239 	if (!cfg->coherent_walk)
240 		dma_unmap_single(cfg->iommu_dev, __arm_lpae_dma_addr(pages),
241 				 size, DMA_TO_DEVICE);
242 	free_pages((unsigned long)pages, get_order(size));
243 }
244 
__arm_lpae_sync_pte(arm_lpae_iopte * ptep,int num_entries,struct io_pgtable_cfg * cfg)245 static void __arm_lpae_sync_pte(arm_lpae_iopte *ptep, int num_entries,
246 				struct io_pgtable_cfg *cfg)
247 {
248 	dma_sync_single_for_device(cfg->iommu_dev, __arm_lpae_dma_addr(ptep),
249 				   sizeof(*ptep) * num_entries, DMA_TO_DEVICE);
250 }
251 
__arm_lpae_clear_pte(arm_lpae_iopte * ptep,struct io_pgtable_cfg * cfg)252 static void __arm_lpae_clear_pte(arm_lpae_iopte *ptep, struct io_pgtable_cfg *cfg)
253 {
254 
255 	*ptep = 0;
256 
257 	if (!cfg->coherent_walk)
258 		__arm_lpae_sync_pte(ptep, 1, cfg);
259 }
260 
261 static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
262 			       struct iommu_iotlb_gather *gather,
263 			       unsigned long iova, size_t size, size_t pgcount,
264 			       int lvl, arm_lpae_iopte *ptep);
265 
__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)266 static void __arm_lpae_init_pte(struct arm_lpae_io_pgtable *data,
267 				phys_addr_t paddr, arm_lpae_iopte prot,
268 				int lvl, int num_entries, arm_lpae_iopte *ptep)
269 {
270 	arm_lpae_iopte pte = prot;
271 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
272 	size_t sz = ARM_LPAE_BLOCK_SIZE(lvl, data);
273 	int i;
274 
275 	if (data->iop.fmt != ARM_MALI_LPAE && lvl == ARM_LPAE_MAX_LEVELS - 1)
276 		pte |= ARM_LPAE_PTE_TYPE_PAGE;
277 	else
278 		pte |= ARM_LPAE_PTE_TYPE_BLOCK;
279 
280 	for (i = 0; i < num_entries; i++)
281 		ptep[i] = pte | paddr_to_iopte(paddr + i * sz, data);
282 
283 	if (!cfg->coherent_walk)
284 		__arm_lpae_sync_pte(ptep, num_entries, cfg);
285 }
286 
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)287 static int arm_lpae_init_pte(struct arm_lpae_io_pgtable *data,
288 			     unsigned long iova, phys_addr_t paddr,
289 			     arm_lpae_iopte prot, int lvl, int num_entries,
290 			     arm_lpae_iopte *ptep)
291 {
292 	int i;
293 
294 	for (i = 0; i < num_entries; i++)
295 		if (iopte_leaf(ptep[i], lvl, data->iop.fmt)) {
296 			/* We require an unmap first */
297 			WARN_ON(!selftest_running);
298 			return -EEXIST;
299 		} else if (iopte_type(ptep[i]) == ARM_LPAE_PTE_TYPE_TABLE) {
300 			/*
301 			 * We need to unmap and free the old table before
302 			 * overwriting it with a block entry.
303 			 */
304 			arm_lpae_iopte *tblp;
305 			size_t sz = ARM_LPAE_BLOCK_SIZE(lvl, data);
306 
307 			tblp = ptep - ARM_LPAE_LVL_IDX(iova, lvl, data);
308 			if (__arm_lpae_unmap(data, NULL, iova + i * sz, sz, 1,
309 					     lvl, tblp) != sz) {
310 				WARN_ON(1);
311 				return -EINVAL;
312 			}
313 		}
314 
315 	__arm_lpae_init_pte(data, paddr, prot, lvl, num_entries, ptep);
316 	return 0;
317 }
318 
arm_lpae_install_table(arm_lpae_iopte * table,arm_lpae_iopte * ptep,arm_lpae_iopte curr,struct arm_lpae_io_pgtable * data)319 static arm_lpae_iopte arm_lpae_install_table(arm_lpae_iopte *table,
320 					     arm_lpae_iopte *ptep,
321 					     arm_lpae_iopte curr,
322 					     struct arm_lpae_io_pgtable *data)
323 {
324 	arm_lpae_iopte old, new;
325 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
326 
327 	new = paddr_to_iopte(__pa(table), data) | ARM_LPAE_PTE_TYPE_TABLE;
328 	if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS)
329 		new |= ARM_LPAE_PTE_NSTABLE;
330 
331 	/*
332 	 * Ensure the table itself is visible before its PTE can be.
333 	 * Whilst we could get away with cmpxchg64_release below, this
334 	 * doesn't have any ordering semantics when !CONFIG_SMP.
335 	 */
336 	dma_wmb();
337 
338 	old = cmpxchg64_relaxed(ptep, curr, new);
339 
340 	if (cfg->coherent_walk || (old & ARM_LPAE_PTE_SW_SYNC))
341 		return old;
342 
343 	/* Even if it's not ours, there's no point waiting; just kick it */
344 	__arm_lpae_sync_pte(ptep, 1, cfg);
345 	if (old == curr)
346 		WRITE_ONCE(*ptep, new | ARM_LPAE_PTE_SW_SYNC);
347 
348 	return old;
349 }
350 
__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)351 static int __arm_lpae_map(struct arm_lpae_io_pgtable *data, unsigned long iova,
352 			  phys_addr_t paddr, size_t size, size_t pgcount,
353 			  arm_lpae_iopte prot, int lvl, arm_lpae_iopte *ptep,
354 			  gfp_t gfp, size_t *mapped)
355 {
356 	arm_lpae_iopte *cptep, pte;
357 	size_t block_size = ARM_LPAE_BLOCK_SIZE(lvl, data);
358 	size_t tblsz = ARM_LPAE_GRANULE(data);
359 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
360 	int ret = 0, num_entries, max_entries, map_idx_start;
361 
362 	/* Find our entry at the current level */
363 	map_idx_start = ARM_LPAE_LVL_IDX(iova, lvl, data);
364 	ptep += map_idx_start;
365 
366 	/* If we can install a leaf entry at this level, then do so */
367 	if (size == block_size) {
368 		max_entries = ARM_LPAE_PTES_PER_TABLE(data) - map_idx_start;
369 		num_entries = min_t(int, pgcount, max_entries);
370 		ret = arm_lpae_init_pte(data, iova, paddr, prot, lvl, num_entries, ptep);
371 		if (!ret && mapped)
372 			*mapped += num_entries * size;
373 
374 		return ret;
375 	}
376 
377 	/* We can't allocate tables at the final level */
378 	if (WARN_ON(lvl >= ARM_LPAE_MAX_LEVELS - 1))
379 		return -EINVAL;
380 
381 	/* Grab a pointer to the next level */
382 	pte = READ_ONCE(*ptep);
383 	if (!pte) {
384 		cptep = __arm_lpae_alloc_pages(tblsz, gfp, cfg);
385 		if (!cptep)
386 			return -ENOMEM;
387 
388 		pte = arm_lpae_install_table(cptep, ptep, 0, data);
389 		if (pte)
390 			__arm_lpae_free_pages(cptep, tblsz, cfg);
391 	} else if (!cfg->coherent_walk && !(pte & ARM_LPAE_PTE_SW_SYNC)) {
392 		__arm_lpae_sync_pte(ptep, 1, cfg);
393 	}
394 
395 	if (pte && !iopte_leaf(pte, lvl, data->iop.fmt)) {
396 		cptep = iopte_deref(pte, data);
397 	} else if (pte) {
398 		/* We require an unmap first */
399 		WARN_ON(!selftest_running);
400 		return -EEXIST;
401 	}
402 
403 	/* Rinse, repeat */
404 	return __arm_lpae_map(data, iova, paddr, size, pgcount, prot, lvl + 1,
405 			      cptep, gfp, mapped);
406 }
407 
arm_lpae_prot_to_pte(struct arm_lpae_io_pgtable * data,int prot)408 static arm_lpae_iopte arm_lpae_prot_to_pte(struct arm_lpae_io_pgtable *data,
409 					   int prot)
410 {
411 	arm_lpae_iopte pte;
412 
413 	if (data->iop.fmt == APPLE_DART) {
414 		pte = 0;
415 		if (!(prot & IOMMU_WRITE))
416 			pte |= APPLE_DART_PTE_PROT_NO_WRITE;
417 		if (!(prot & IOMMU_READ))
418 			pte |= APPLE_DART_PTE_PROT_NO_READ;
419 		return pte;
420 	}
421 
422 	if (data->iop.fmt == ARM_64_LPAE_S1 ||
423 	    data->iop.fmt == ARM_32_LPAE_S1) {
424 		pte = ARM_LPAE_PTE_nG;
425 		if (!(prot & IOMMU_WRITE) && (prot & IOMMU_READ))
426 			pte |= ARM_LPAE_PTE_AP_RDONLY;
427 		if (!(prot & IOMMU_PRIV))
428 			pte |= ARM_LPAE_PTE_AP_UNPRIV;
429 	} else {
430 		pte = ARM_LPAE_PTE_HAP_FAULT;
431 		if (prot & IOMMU_READ)
432 			pte |= ARM_LPAE_PTE_HAP_READ;
433 		if (prot & IOMMU_WRITE)
434 			pte |= ARM_LPAE_PTE_HAP_WRITE;
435 	}
436 
437 	/*
438 	 * Note that this logic is structured to accommodate Mali LPAE
439 	 * having stage-1-like attributes but stage-2-like permissions.
440 	 */
441 	if (data->iop.fmt == ARM_64_LPAE_S2 ||
442 	    data->iop.fmt == ARM_32_LPAE_S2) {
443 		if (prot & IOMMU_MMIO)
444 			pte |= ARM_LPAE_PTE_MEMATTR_DEV;
445 		else if (prot & IOMMU_CACHE)
446 			pte |= ARM_LPAE_PTE_MEMATTR_OIWB;
447 		else
448 			pte |= ARM_LPAE_PTE_MEMATTR_NC;
449 	} else {
450 		if (prot & IOMMU_MMIO)
451 			pte |= (ARM_LPAE_MAIR_ATTR_IDX_DEV
452 				<< ARM_LPAE_PTE_ATTRINDX_SHIFT);
453 		else if ((prot & IOMMU_CACHE) && (prot & IOMMU_SYS_CACHE_NWA))
454 			pte |= (ARM_LPAE_MAIR_ATTR_IDX_ICACHE_OCACHE_NWA
455 				<< ARM_LPAE_PTE_ATTRINDX_SHIFT);
456 		/* IOMMU_CACHE + IOMMU_SYS_CACHE equivalent to IOMMU_CACHE */
457 		else if (prot & IOMMU_CACHE)
458 			pte |= (ARM_LPAE_MAIR_ATTR_IDX_CACHE
459 				<< ARM_LPAE_PTE_ATTRINDX_SHIFT);
460 		else if (prot & IOMMU_SYS_CACHE)
461 			pte |= (ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE
462 				<< ARM_LPAE_PTE_ATTRINDX_SHIFT);
463 		else if (prot & IOMMU_SYS_CACHE_NWA)
464 			pte |= (ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE_NWA
465 				<< ARM_LPAE_PTE_ATTRINDX_SHIFT);
466 	}
467 
468 	/*
469 	 * Also Mali has its own notions of shareability wherein its Inner
470 	 * domain covers the cores within the GPU, and its Outer domain is
471 	 * "outside the GPU" (i.e. either the Inner or System domain in CPU
472 	 * terms, depending on coherency).
473 	 */
474 	if (prot & IOMMU_CACHE && data->iop.fmt != ARM_MALI_LPAE)
475 		pte |= ARM_LPAE_PTE_SH_IS;
476 	else
477 		pte |= ARM_LPAE_PTE_SH_OS;
478 
479 	if (prot & IOMMU_NOEXEC)
480 		pte |= ARM_LPAE_PTE_XN;
481 
482 	if (data->iop.cfg.quirks & IO_PGTABLE_QUIRK_ARM_NS)
483 		pte |= ARM_LPAE_PTE_NS;
484 
485 	if (data->iop.fmt != ARM_MALI_LPAE)
486 		pte |= ARM_LPAE_PTE_AF;
487 
488 	return pte;
489 }
490 
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)491 static int arm_lpae_map_pages(struct io_pgtable_ops *ops, unsigned long iova,
492 			      phys_addr_t paddr, size_t pgsize, size_t pgcount,
493 			      int iommu_prot, gfp_t gfp, size_t *mapped)
494 {
495 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
496 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
497 	arm_lpae_iopte *ptep = data->pgd;
498 	int ret, lvl = data->start_level;
499 	arm_lpae_iopte prot;
500 	long iaext = (s64)iova >> cfg->ias;
501 
502 	if (WARN_ON(!pgsize || (pgsize & cfg->pgsize_bitmap) != pgsize))
503 		return -EINVAL;
504 
505 	if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_TTBR1)
506 		iaext = ~iaext;
507 	if (WARN_ON(iaext || paddr >> cfg->oas))
508 		return -ERANGE;
509 
510 	/* If no access, then nothing to do */
511 	if (!(iommu_prot & (IOMMU_READ | IOMMU_WRITE)))
512 		return 0;
513 
514 	prot = arm_lpae_prot_to_pte(data, iommu_prot);
515 	ret = __arm_lpae_map(data, iova, paddr, pgsize, pgcount, prot, lvl,
516 			     ptep, gfp, mapped);
517 	/*
518 	 * Synchronise all PTE updates for the new mapping before there's
519 	 * a chance for anything to kick off a table walk for the new iova.
520 	 */
521 	wmb();
522 
523 	return ret;
524 }
525 
arm_lpae_map(struct io_pgtable_ops * ops,unsigned long iova,phys_addr_t paddr,size_t size,int iommu_prot,gfp_t gfp)526 static int arm_lpae_map(struct io_pgtable_ops *ops, unsigned long iova,
527 			phys_addr_t paddr, size_t size, int iommu_prot, gfp_t gfp)
528 {
529 	return arm_lpae_map_pages(ops, iova, paddr, size, 1, iommu_prot, gfp,
530 				  NULL);
531 }
532 
__arm_lpae_free_pgtable(struct arm_lpae_io_pgtable * data,int lvl,arm_lpae_iopte * ptep)533 static void __arm_lpae_free_pgtable(struct arm_lpae_io_pgtable *data, int lvl,
534 				    arm_lpae_iopte *ptep)
535 {
536 	arm_lpae_iopte *start, *end;
537 	unsigned long table_size;
538 
539 	if (lvl == data->start_level)
540 		table_size = ARM_LPAE_PGD_SIZE(data);
541 	else
542 		table_size = ARM_LPAE_GRANULE(data);
543 
544 	start = ptep;
545 
546 	/* Only leaf entries at the last level */
547 	if (lvl == ARM_LPAE_MAX_LEVELS - 1)
548 		end = ptep;
549 	else
550 		end = (void *)ptep + table_size;
551 
552 	while (ptep != end) {
553 		arm_lpae_iopte pte = *ptep++;
554 
555 		if (!pte || iopte_leaf(pte, lvl, data->iop.fmt))
556 			continue;
557 
558 		__arm_lpae_free_pgtable(data, lvl + 1, iopte_deref(pte, data));
559 	}
560 
561 	__arm_lpae_free_pages(start, table_size, &data->iop.cfg);
562 }
563 
arm_lpae_free_pgtable(struct io_pgtable * iop)564 static void arm_lpae_free_pgtable(struct io_pgtable *iop)
565 {
566 	struct arm_lpae_io_pgtable *data = io_pgtable_to_data(iop);
567 
568 	__arm_lpae_free_pgtable(data, data->start_level, data->pgd);
569 	kfree(data);
570 }
571 
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)572 static size_t arm_lpae_split_blk_unmap(struct arm_lpae_io_pgtable *data,
573 				       struct iommu_iotlb_gather *gather,
574 				       unsigned long iova, size_t size,
575 				       arm_lpae_iopte blk_pte, int lvl,
576 				       arm_lpae_iopte *ptep, size_t pgcount)
577 {
578 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
579 	arm_lpae_iopte pte, *tablep;
580 	phys_addr_t blk_paddr;
581 	size_t tablesz = ARM_LPAE_GRANULE(data);
582 	size_t split_sz = ARM_LPAE_BLOCK_SIZE(lvl, data);
583 	int ptes_per_table = ARM_LPAE_PTES_PER_TABLE(data);
584 	int i, unmap_idx_start = -1, num_entries = 0, max_entries;
585 
586 	if (WARN_ON(lvl == ARM_LPAE_MAX_LEVELS))
587 		return 0;
588 
589 	tablep = __arm_lpae_alloc_pages(tablesz, GFP_ATOMIC, cfg);
590 	if (!tablep)
591 		return 0; /* Bytes unmapped */
592 
593 	if (size == split_sz) {
594 		unmap_idx_start = ARM_LPAE_LVL_IDX(iova, lvl, data);
595 		max_entries = ptes_per_table - unmap_idx_start;
596 		num_entries = min_t(int, pgcount, max_entries);
597 	}
598 
599 	blk_paddr = iopte_to_paddr(blk_pte, data);
600 	pte = iopte_prot(blk_pte);
601 
602 	for (i = 0; i < ptes_per_table; i++, blk_paddr += split_sz) {
603 		/* Unmap! */
604 		if (i >= unmap_idx_start && i < (unmap_idx_start + num_entries))
605 			continue;
606 
607 		__arm_lpae_init_pte(data, blk_paddr, pte, lvl, 1, &tablep[i]);
608 	}
609 
610 	pte = arm_lpae_install_table(tablep, ptep, blk_pte, data);
611 	if (pte != blk_pte) {
612 		__arm_lpae_free_pages(tablep, tablesz, cfg);
613 		/*
614 		 * We may race against someone unmapping another part of this
615 		 * block, but anything else is invalid. We can't misinterpret
616 		 * a page entry here since we're never at the last level.
617 		 */
618 		if (iopte_type(pte) != ARM_LPAE_PTE_TYPE_TABLE)
619 			return 0;
620 
621 		tablep = iopte_deref(pte, data);
622 	} else if (unmap_idx_start >= 0) {
623 		for (i = 0; i < num_entries; i++)
624 			io_pgtable_tlb_add_page(&data->iop, gather, iova + i * size, size);
625 
626 		return num_entries * size;
627 	}
628 
629 	return __arm_lpae_unmap(data, gather, iova, size, pgcount, lvl, tablep);
630 }
631 
__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)632 static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
633 			       struct iommu_iotlb_gather *gather,
634 			       unsigned long iova, size_t size, size_t pgcount,
635 			       int lvl, arm_lpae_iopte *ptep)
636 {
637 	arm_lpae_iopte pte;
638 	struct io_pgtable *iop = &data->iop;
639 	int i = 0, num_entries, max_entries, unmap_idx_start;
640 
641 	/* Something went horribly wrong and we ran out of page table */
642 	if (WARN_ON(lvl == ARM_LPAE_MAX_LEVELS))
643 		return 0;
644 
645 	unmap_idx_start = ARM_LPAE_LVL_IDX(iova, lvl, data);
646 	ptep += unmap_idx_start;
647 	pte = READ_ONCE(*ptep);
648 	if (WARN_ON(!pte))
649 		return 0;
650 
651 	/* If the size matches this level, we're in the right place */
652 	if (size == ARM_LPAE_BLOCK_SIZE(lvl, data)) {
653 		max_entries = ARM_LPAE_PTES_PER_TABLE(data) - unmap_idx_start;
654 		num_entries = min_t(int, pgcount, max_entries);
655 
656 		while (i < num_entries) {
657 			pte = READ_ONCE(*ptep);
658 			if (WARN_ON(!pte))
659 				break;
660 
661 			__arm_lpae_clear_pte(ptep, &iop->cfg);
662 
663 			if (!iopte_leaf(pte, lvl, iop->fmt)) {
664 				/* Also flush any partial walks */
665 				io_pgtable_tlb_flush_walk(iop, iova + i * size, size,
666 							  ARM_LPAE_GRANULE(data));
667 				__arm_lpae_free_pgtable(data, lvl + 1, iopte_deref(pte, data));
668 			} else if (!iommu_iotlb_gather_queued(gather)) {
669 				io_pgtable_tlb_add_page(iop, gather, iova + i * size, size);
670 			}
671 
672 			ptep++;
673 			i++;
674 		}
675 
676 		return i * size;
677 	} else if (iopte_leaf(pte, lvl, iop->fmt)) {
678 		/*
679 		 * Insert a table at the next level to map the old region,
680 		 * minus the part we want to unmap
681 		 */
682 		return arm_lpae_split_blk_unmap(data, gather, iova, size, pte,
683 						lvl + 1, ptep, pgcount);
684 	}
685 
686 	/* Keep on walkin' */
687 	ptep = iopte_deref(pte, data);
688 	return __arm_lpae_unmap(data, gather, iova, size, pgcount, lvl + 1, ptep);
689 }
690 
arm_lpae_unmap_pages(struct io_pgtable_ops * ops,unsigned long iova,size_t pgsize,size_t pgcount,struct iommu_iotlb_gather * gather)691 static size_t arm_lpae_unmap_pages(struct io_pgtable_ops *ops, unsigned long iova,
692 				   size_t pgsize, size_t pgcount,
693 				   struct iommu_iotlb_gather *gather)
694 {
695 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
696 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
697 	arm_lpae_iopte *ptep = data->pgd;
698 	long iaext = (s64)iova >> cfg->ias;
699 
700 	if (WARN_ON(!pgsize || (pgsize & cfg->pgsize_bitmap) != pgsize || !pgcount))
701 		return 0;
702 
703 	if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_TTBR1)
704 		iaext = ~iaext;
705 	if (WARN_ON(iaext))
706 		return 0;
707 
708 	return __arm_lpae_unmap(data, gather, iova, pgsize, pgcount,
709 				data->start_level, ptep);
710 }
711 
arm_lpae_unmap(struct io_pgtable_ops * ops,unsigned long iova,size_t size,struct iommu_iotlb_gather * gather)712 static size_t arm_lpae_unmap(struct io_pgtable_ops *ops, unsigned long iova,
713 			     size_t size, struct iommu_iotlb_gather *gather)
714 {
715 	return arm_lpae_unmap_pages(ops, iova, size, 1, gather);
716 }
717 
arm_lpae_iova_to_phys(struct io_pgtable_ops * ops,unsigned long iova)718 static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops,
719 					 unsigned long iova)
720 {
721 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
722 	arm_lpae_iopte pte, *ptep = data->pgd;
723 	int lvl = data->start_level;
724 
725 	do {
726 		/* Valid IOPTE pointer? */
727 		if (!ptep)
728 			return 0;
729 
730 		/* Grab the IOPTE we're interested in */
731 		ptep += ARM_LPAE_LVL_IDX(iova, lvl, data);
732 		pte = READ_ONCE(*ptep);
733 
734 		/* Valid entry? */
735 		if (!pte)
736 			return 0;
737 
738 		/* Leaf entry? */
739 		if (iopte_leaf(pte, lvl, data->iop.fmt))
740 			goto found_translation;
741 
742 		/* Take it to the next level */
743 		ptep = iopte_deref(pte, data);
744 	} while (++lvl < ARM_LPAE_MAX_LEVELS);
745 
746 	/* Ran out of page tables to walk */
747 	return 0;
748 
749 found_translation:
750 	iova &= (ARM_LPAE_BLOCK_SIZE(lvl, data) - 1);
751 	return iopte_to_paddr(pte, data) | iova;
752 }
753 
arm_lpae_restrict_pgsizes(struct io_pgtable_cfg * cfg)754 static void arm_lpae_restrict_pgsizes(struct io_pgtable_cfg *cfg)
755 {
756 	unsigned long granule, page_sizes;
757 	unsigned int max_addr_bits = 48;
758 
759 	/*
760 	 * We need to restrict the supported page sizes to match the
761 	 * translation regime for a particular granule. Aim to match
762 	 * the CPU page size if possible, otherwise prefer smaller sizes.
763 	 * While we're at it, restrict the block sizes to match the
764 	 * chosen granule.
765 	 */
766 	if (cfg->pgsize_bitmap & PAGE_SIZE)
767 		granule = PAGE_SIZE;
768 	else if (cfg->pgsize_bitmap & ~PAGE_MASK)
769 		granule = 1UL << __fls(cfg->pgsize_bitmap & ~PAGE_MASK);
770 	else if (cfg->pgsize_bitmap & PAGE_MASK)
771 		granule = 1UL << __ffs(cfg->pgsize_bitmap & PAGE_MASK);
772 	else
773 		granule = 0;
774 
775 	switch (granule) {
776 	case SZ_4K:
777 		page_sizes = (SZ_4K | SZ_2M | SZ_1G);
778 		break;
779 	case SZ_16K:
780 		page_sizes = (SZ_16K | SZ_32M);
781 		break;
782 	case SZ_64K:
783 		max_addr_bits = 52;
784 		page_sizes = (SZ_64K | SZ_512M);
785 		if (cfg->oas > 48)
786 			page_sizes |= 1ULL << 42; /* 4TB */
787 		break;
788 	default:
789 		page_sizes = 0;
790 	}
791 
792 	cfg->pgsize_bitmap &= page_sizes;
793 	cfg->ias = min(cfg->ias, max_addr_bits);
794 	cfg->oas = min(cfg->oas, max_addr_bits);
795 }
796 
797 static struct arm_lpae_io_pgtable *
arm_lpae_alloc_pgtable(struct io_pgtable_cfg * cfg)798 arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg)
799 {
800 	struct arm_lpae_io_pgtable *data;
801 	int levels, va_bits, pg_shift;
802 
803 	arm_lpae_restrict_pgsizes(cfg);
804 
805 	if (!(cfg->pgsize_bitmap & (SZ_4K | SZ_16K | SZ_64K)))
806 		return NULL;
807 
808 	if (cfg->ias > ARM_LPAE_MAX_ADDR_BITS)
809 		return NULL;
810 
811 	if (cfg->oas > ARM_LPAE_MAX_ADDR_BITS)
812 		return NULL;
813 
814 	data = kmalloc(sizeof(*data), GFP_KERNEL);
815 	if (!data)
816 		return NULL;
817 
818 	pg_shift = __ffs(cfg->pgsize_bitmap);
819 	data->bits_per_level = pg_shift - ilog2(sizeof(arm_lpae_iopte));
820 
821 	va_bits = cfg->ias - pg_shift;
822 	levels = DIV_ROUND_UP(va_bits, data->bits_per_level);
823 	data->start_level = ARM_LPAE_MAX_LEVELS - levels;
824 
825 	/* Calculate the actual size of our pgd (without concatenation) */
826 	data->pgd_bits = va_bits - (data->bits_per_level * (levels - 1));
827 
828 	data->iop.ops = (struct io_pgtable_ops) {
829 		.map		= arm_lpae_map,
830 		.map_pages	= arm_lpae_map_pages,
831 		.unmap		= arm_lpae_unmap,
832 		.unmap_pages	= arm_lpae_unmap_pages,
833 		.iova_to_phys	= arm_lpae_iova_to_phys,
834 	};
835 
836 	return data;
837 }
838 
839 static struct io_pgtable *
arm_64_lpae_alloc_pgtable_s1(struct io_pgtable_cfg * cfg,void * cookie)840 arm_64_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie)
841 {
842 	u64 reg;
843 	struct arm_lpae_io_pgtable *data;
844 	typeof(&cfg->arm_lpae_s1_cfg.tcr) tcr = &cfg->arm_lpae_s1_cfg.tcr;
845 	bool tg1;
846 
847 	if (cfg->quirks & ~(IO_PGTABLE_QUIRK_ARM_NS |
848 			    IO_PGTABLE_QUIRK_ARM_TTBR1 |
849 			    IO_PGTABLE_QUIRK_ARM_OUTER_WBWA))
850 		return NULL;
851 
852 	data = arm_lpae_alloc_pgtable(cfg);
853 	if (!data)
854 		return NULL;
855 
856 	/* TCR */
857 	if (cfg->coherent_walk) {
858 		tcr->sh = ARM_LPAE_TCR_SH_IS;
859 		tcr->irgn = ARM_LPAE_TCR_RGN_WBWA;
860 		tcr->orgn = ARM_LPAE_TCR_RGN_WBWA;
861 		if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_OUTER_WBWA)
862 			goto out_free_data;
863 	} else {
864 		tcr->sh = ARM_LPAE_TCR_SH_OS;
865 		tcr->irgn = ARM_LPAE_TCR_RGN_NC;
866 		if (!(cfg->quirks & IO_PGTABLE_QUIRK_ARM_OUTER_WBWA))
867 			tcr->orgn = ARM_LPAE_TCR_RGN_NC;
868 		else
869 			tcr->orgn = ARM_LPAE_TCR_RGN_WBWA;
870 	}
871 
872 	tg1 = cfg->quirks & IO_PGTABLE_QUIRK_ARM_TTBR1;
873 	switch (ARM_LPAE_GRANULE(data)) {
874 	case SZ_4K:
875 		tcr->tg = tg1 ? ARM_LPAE_TCR_TG1_4K : ARM_LPAE_TCR_TG0_4K;
876 		break;
877 	case SZ_16K:
878 		tcr->tg = tg1 ? ARM_LPAE_TCR_TG1_16K : ARM_LPAE_TCR_TG0_16K;
879 		break;
880 	case SZ_64K:
881 		tcr->tg = tg1 ? ARM_LPAE_TCR_TG1_64K : ARM_LPAE_TCR_TG0_64K;
882 		break;
883 	}
884 
885 	switch (cfg->oas) {
886 	case 32:
887 		tcr->ips = ARM_LPAE_TCR_PS_32_BIT;
888 		break;
889 	case 36:
890 		tcr->ips = ARM_LPAE_TCR_PS_36_BIT;
891 		break;
892 	case 40:
893 		tcr->ips = ARM_LPAE_TCR_PS_40_BIT;
894 		break;
895 	case 42:
896 		tcr->ips = ARM_LPAE_TCR_PS_42_BIT;
897 		break;
898 	case 44:
899 		tcr->ips = ARM_LPAE_TCR_PS_44_BIT;
900 		break;
901 	case 48:
902 		tcr->ips = ARM_LPAE_TCR_PS_48_BIT;
903 		break;
904 	case 52:
905 		tcr->ips = ARM_LPAE_TCR_PS_52_BIT;
906 		break;
907 	default:
908 		goto out_free_data;
909 	}
910 
911 	tcr->tsz = 64ULL - cfg->ias;
912 
913 	/* MAIRs */
914 	reg = (ARM_LPAE_MAIR_ATTR_NC
915 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_NC)) |
916 	      (ARM_LPAE_MAIR_ATTR_WBRWA
917 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_CACHE)) |
918 	      (ARM_LPAE_MAIR_ATTR_DEVICE
919 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_DEV)) |
920 	      (ARM_LPAE_MAIR_ATTR_INC_OWBRWA
921 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE)) |
922 	      (ARM_LPAE_MAIR_ATTR_INC_OWBRANWA
923 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE_NWA)) |
924 	      (ARM_LPAE_MAIR_ATTR_IWBRWA_OWBRANWA
925 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_ICACHE_OCACHE_NWA));
926 
927 	cfg->arm_lpae_s1_cfg.mair = reg;
928 
929 	/* Looking good; allocate a pgd */
930 	data->pgd = __arm_lpae_alloc_pages(ARM_LPAE_PGD_SIZE(data),
931 					   GFP_KERNEL, cfg);
932 	if (!data->pgd)
933 		goto out_free_data;
934 
935 	/* Ensure the empty pgd is visible before any actual TTBR write */
936 	wmb();
937 
938 	/* TTBR */
939 	cfg->arm_lpae_s1_cfg.ttbr = virt_to_phys(data->pgd);
940 	return &data->iop;
941 
942 out_free_data:
943 	kfree(data);
944 	return NULL;
945 }
946 
947 static struct io_pgtable *
arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg * cfg,void * cookie)948 arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
949 {
950 	u64 sl;
951 	struct arm_lpae_io_pgtable *data;
952 	typeof(&cfg->arm_lpae_s2_cfg.vtcr) vtcr = &cfg->arm_lpae_s2_cfg.vtcr;
953 
954 	/* The NS quirk doesn't apply at stage 2 */
955 	if (cfg->quirks)
956 		return NULL;
957 
958 	data = arm_lpae_alloc_pgtable(cfg);
959 	if (!data)
960 		return NULL;
961 
962 	/*
963 	 * Concatenate PGDs at level 1 if possible in order to reduce
964 	 * the depth of the stage-2 walk.
965 	 */
966 	if (data->start_level == 0) {
967 		unsigned long pgd_pages;
968 
969 		pgd_pages = ARM_LPAE_PGD_SIZE(data) / sizeof(arm_lpae_iopte);
970 		if (pgd_pages <= ARM_LPAE_S2_MAX_CONCAT_PAGES) {
971 			data->pgd_bits += data->bits_per_level;
972 			data->start_level++;
973 		}
974 	}
975 
976 	/* VTCR */
977 	if (cfg->coherent_walk) {
978 		vtcr->sh = ARM_LPAE_TCR_SH_IS;
979 		vtcr->irgn = ARM_LPAE_TCR_RGN_WBWA;
980 		vtcr->orgn = ARM_LPAE_TCR_RGN_WBWA;
981 	} else {
982 		vtcr->sh = ARM_LPAE_TCR_SH_OS;
983 		vtcr->irgn = ARM_LPAE_TCR_RGN_NC;
984 		vtcr->orgn = ARM_LPAE_TCR_RGN_NC;
985 	}
986 
987 	sl = data->start_level;
988 
989 	switch (ARM_LPAE_GRANULE(data)) {
990 	case SZ_4K:
991 		vtcr->tg = ARM_LPAE_TCR_TG0_4K;
992 		sl++; /* SL0 format is different for 4K granule size */
993 		break;
994 	case SZ_16K:
995 		vtcr->tg = ARM_LPAE_TCR_TG0_16K;
996 		break;
997 	case SZ_64K:
998 		vtcr->tg = ARM_LPAE_TCR_TG0_64K;
999 		break;
1000 	}
1001 
1002 	switch (cfg->oas) {
1003 	case 32:
1004 		vtcr->ps = ARM_LPAE_TCR_PS_32_BIT;
1005 		break;
1006 	case 36:
1007 		vtcr->ps = ARM_LPAE_TCR_PS_36_BIT;
1008 		break;
1009 	case 40:
1010 		vtcr->ps = ARM_LPAE_TCR_PS_40_BIT;
1011 		break;
1012 	case 42:
1013 		vtcr->ps = ARM_LPAE_TCR_PS_42_BIT;
1014 		break;
1015 	case 44:
1016 		vtcr->ps = ARM_LPAE_TCR_PS_44_BIT;
1017 		break;
1018 	case 48:
1019 		vtcr->ps = ARM_LPAE_TCR_PS_48_BIT;
1020 		break;
1021 	case 52:
1022 		vtcr->ps = ARM_LPAE_TCR_PS_52_BIT;
1023 		break;
1024 	default:
1025 		goto out_free_data;
1026 	}
1027 
1028 	vtcr->tsz = 64ULL - cfg->ias;
1029 	vtcr->sl = ~sl & ARM_LPAE_VTCR_SL0_MASK;
1030 
1031 	/* Allocate pgd pages */
1032 	data->pgd = __arm_lpae_alloc_pages(ARM_LPAE_PGD_SIZE(data),
1033 					   GFP_KERNEL, cfg);
1034 	if (!data->pgd)
1035 		goto out_free_data;
1036 
1037 	/* Ensure the empty pgd is visible before any actual TTBR write */
1038 	wmb();
1039 
1040 	/* VTTBR */
1041 	cfg->arm_lpae_s2_cfg.vttbr = virt_to_phys(data->pgd);
1042 	return &data->iop;
1043 
1044 out_free_data:
1045 	kfree(data);
1046 	return NULL;
1047 }
1048 
1049 static struct io_pgtable *
arm_32_lpae_alloc_pgtable_s1(struct io_pgtable_cfg * cfg,void * cookie)1050 arm_32_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie)
1051 {
1052 	if (cfg->ias > 32 || cfg->oas > 40)
1053 		return NULL;
1054 
1055 	cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
1056 	return arm_64_lpae_alloc_pgtable_s1(cfg, cookie);
1057 }
1058 
1059 static struct io_pgtable *
arm_32_lpae_alloc_pgtable_s2(struct io_pgtable_cfg * cfg,void * cookie)1060 arm_32_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
1061 {
1062 	if (cfg->ias > 40 || cfg->oas > 40)
1063 		return NULL;
1064 
1065 	cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
1066 	return arm_64_lpae_alloc_pgtable_s2(cfg, cookie);
1067 }
1068 
1069 static struct io_pgtable *
arm_mali_lpae_alloc_pgtable(struct io_pgtable_cfg * cfg,void * cookie)1070 arm_mali_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)
1071 {
1072 	struct arm_lpae_io_pgtable *data;
1073 
1074 	/* No quirks for Mali (hopefully) */
1075 	if (cfg->quirks)
1076 		return NULL;
1077 
1078 	if (cfg->ias > 48 || cfg->oas > 40)
1079 		return NULL;
1080 
1081 	cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
1082 
1083 	data = arm_lpae_alloc_pgtable(cfg);
1084 	if (!data)
1085 		return NULL;
1086 
1087 	/* Mali seems to need a full 4-level table regardless of IAS */
1088 	if (data->start_level > 0) {
1089 		data->start_level = 0;
1090 		data->pgd_bits = 0;
1091 	}
1092 	/*
1093 	 * MEMATTR: Mali has no actual notion of a non-cacheable type, so the
1094 	 * best we can do is mimic the out-of-tree driver and hope that the
1095 	 * "implementation-defined caching policy" is good enough. Similarly,
1096 	 * we'll use it for the sake of a valid attribute for our 'device'
1097 	 * index, although callers should never request that in practice.
1098 	 */
1099 	cfg->arm_mali_lpae_cfg.memattr =
1100 		(ARM_MALI_LPAE_MEMATTR_IMP_DEF
1101 		 << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_NC)) |
1102 		(ARM_MALI_LPAE_MEMATTR_WRITE_ALLOC
1103 		 << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_CACHE)) |
1104 		(ARM_MALI_LPAE_MEMATTR_IMP_DEF
1105 		 << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_DEV));
1106 
1107 	data->pgd = __arm_lpae_alloc_pages(ARM_LPAE_PGD_SIZE(data), GFP_KERNEL,
1108 					   cfg);
1109 	if (!data->pgd)
1110 		goto out_free_data;
1111 
1112 	/* Ensure the empty pgd is visible before TRANSTAB can be written */
1113 	wmb();
1114 
1115 	cfg->arm_mali_lpae_cfg.transtab = virt_to_phys(data->pgd) |
1116 					  ARM_MALI_LPAE_TTBR_READ_INNER |
1117 					  ARM_MALI_LPAE_TTBR_ADRMODE_TABLE;
1118 	if (cfg->coherent_walk)
1119 		cfg->arm_mali_lpae_cfg.transtab |= ARM_MALI_LPAE_TTBR_SHARE_OUTER;
1120 
1121 	return &data->iop;
1122 
1123 out_free_data:
1124 	kfree(data);
1125 	return NULL;
1126 }
1127 
1128 static struct io_pgtable *
apple_dart_alloc_pgtable(struct io_pgtable_cfg * cfg,void * cookie)1129 apple_dart_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)
1130 {
1131 	struct arm_lpae_io_pgtable *data;
1132 	int i;
1133 
1134 	if (cfg->oas > 36)
1135 		return NULL;
1136 
1137 	data = arm_lpae_alloc_pgtable(cfg);
1138 	if (!data)
1139 		return NULL;
1140 
1141 	/*
1142 	 * The table format itself always uses two levels, but the total VA
1143 	 * space is mapped by four separate tables, making the MMIO registers
1144 	 * an effective "level 1". For simplicity, though, we treat this
1145 	 * equivalently to LPAE stage 2 concatenation at level 2, with the
1146 	 * additional TTBRs each just pointing at consecutive pages.
1147 	 */
1148 	if (data->start_level < 1)
1149 		goto out_free_data;
1150 	if (data->start_level == 1 && data->pgd_bits > 2)
1151 		goto out_free_data;
1152 	if (data->start_level > 1)
1153 		data->pgd_bits = 0;
1154 	data->start_level = 2;
1155 	cfg->apple_dart_cfg.n_ttbrs = 1 << data->pgd_bits;
1156 	data->pgd_bits += data->bits_per_level;
1157 
1158 	data->pgd = __arm_lpae_alloc_pages(ARM_LPAE_PGD_SIZE(data), GFP_KERNEL,
1159 					   cfg);
1160 	if (!data->pgd)
1161 		goto out_free_data;
1162 
1163 	for (i = 0; i < cfg->apple_dart_cfg.n_ttbrs; ++i)
1164 		cfg->apple_dart_cfg.ttbr[i] =
1165 			virt_to_phys(data->pgd + i * ARM_LPAE_GRANULE(data));
1166 
1167 	return &data->iop;
1168 
1169 out_free_data:
1170 	kfree(data);
1171 	return NULL;
1172 }
1173 
1174 struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns = {
1175 	.alloc	= arm_64_lpae_alloc_pgtable_s1,
1176 	.free	= arm_lpae_free_pgtable,
1177 };
1178 
1179 struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns = {
1180 	.alloc	= arm_64_lpae_alloc_pgtable_s2,
1181 	.free	= arm_lpae_free_pgtable,
1182 };
1183 
1184 struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns = {
1185 	.alloc	= arm_32_lpae_alloc_pgtable_s1,
1186 	.free	= arm_lpae_free_pgtable,
1187 };
1188 
1189 struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns = {
1190 	.alloc	= arm_32_lpae_alloc_pgtable_s2,
1191 	.free	= arm_lpae_free_pgtable,
1192 };
1193 
1194 struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns = {
1195 	.alloc	= arm_mali_lpae_alloc_pgtable,
1196 	.free	= arm_lpae_free_pgtable,
1197 };
1198 
1199 struct io_pgtable_init_fns io_pgtable_apple_dart_init_fns = {
1200 	.alloc	= apple_dart_alloc_pgtable,
1201 	.free	= arm_lpae_free_pgtable,
1202 };
1203 
1204 #ifdef CONFIG_IOMMU_IO_PGTABLE_LPAE_SELFTEST
1205 
1206 static struct io_pgtable_cfg *cfg_cookie __initdata;
1207 
dummy_tlb_flush_all(void * cookie)1208 static void __init dummy_tlb_flush_all(void *cookie)
1209 {
1210 	WARN_ON(cookie != cfg_cookie);
1211 }
1212 
dummy_tlb_flush(unsigned long iova,size_t size,size_t granule,void * cookie)1213 static void __init dummy_tlb_flush(unsigned long iova, size_t size,
1214 				   size_t granule, void *cookie)
1215 {
1216 	WARN_ON(cookie != cfg_cookie);
1217 	WARN_ON(!(size & cfg_cookie->pgsize_bitmap));
1218 }
1219 
dummy_tlb_add_page(struct iommu_iotlb_gather * gather,unsigned long iova,size_t granule,void * cookie)1220 static void __init dummy_tlb_add_page(struct iommu_iotlb_gather *gather,
1221 				      unsigned long iova, size_t granule,
1222 				      void *cookie)
1223 {
1224 	dummy_tlb_flush(iova, granule, granule, cookie);
1225 }
1226 
1227 static const struct iommu_flush_ops dummy_tlb_ops __initconst = {
1228 	.tlb_flush_all	= dummy_tlb_flush_all,
1229 	.tlb_flush_walk	= dummy_tlb_flush,
1230 	.tlb_add_page	= dummy_tlb_add_page,
1231 };
1232 
arm_lpae_dump_ops(struct io_pgtable_ops * ops)1233 static void __init arm_lpae_dump_ops(struct io_pgtable_ops *ops)
1234 {
1235 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
1236 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
1237 
1238 	pr_err("cfg: pgsize_bitmap 0x%lx, ias %u-bit\n",
1239 		cfg->pgsize_bitmap, cfg->ias);
1240 	pr_err("data: %d levels, 0x%zx pgd_size, %u pg_shift, %u bits_per_level, pgd @ %p\n",
1241 		ARM_LPAE_MAX_LEVELS - data->start_level, ARM_LPAE_PGD_SIZE(data),
1242 		ilog2(ARM_LPAE_GRANULE(data)), data->bits_per_level, data->pgd);
1243 }
1244 
1245 #define __FAIL(ops, i)	({						\
1246 		WARN(1, "selftest: test failed for fmt idx %d\n", (i));	\
1247 		arm_lpae_dump_ops(ops);					\
1248 		selftest_running = false;				\
1249 		-EFAULT;						\
1250 })
1251 
arm_lpae_run_tests(struct io_pgtable_cfg * cfg)1252 static int __init arm_lpae_run_tests(struct io_pgtable_cfg *cfg)
1253 {
1254 	static const enum io_pgtable_fmt fmts[] __initconst = {
1255 		ARM_64_LPAE_S1,
1256 		ARM_64_LPAE_S2,
1257 	};
1258 
1259 	int i, j;
1260 	unsigned long iova;
1261 	size_t size;
1262 	struct io_pgtable_ops *ops;
1263 
1264 	selftest_running = true;
1265 
1266 	for (i = 0; i < ARRAY_SIZE(fmts); ++i) {
1267 		cfg_cookie = cfg;
1268 		ops = alloc_io_pgtable_ops(fmts[i], cfg, cfg);
1269 		if (!ops) {
1270 			pr_err("selftest: failed to allocate io pgtable ops\n");
1271 			return -ENOMEM;
1272 		}
1273 
1274 		/*
1275 		 * Initial sanity checks.
1276 		 * Empty page tables shouldn't provide any translations.
1277 		 */
1278 		if (ops->iova_to_phys(ops, 42))
1279 			return __FAIL(ops, i);
1280 
1281 		if (ops->iova_to_phys(ops, SZ_1G + 42))
1282 			return __FAIL(ops, i);
1283 
1284 		if (ops->iova_to_phys(ops, SZ_2G + 42))
1285 			return __FAIL(ops, i);
1286 
1287 		/*
1288 		 * Distinct mappings of different granule sizes.
1289 		 */
1290 		iova = 0;
1291 		for_each_set_bit(j, &cfg->pgsize_bitmap, BITS_PER_LONG) {
1292 			size = 1UL << j;
1293 
1294 			if (ops->map(ops, iova, iova, size, IOMMU_READ |
1295 							    IOMMU_WRITE |
1296 							    IOMMU_NOEXEC |
1297 							    IOMMU_CACHE, GFP_KERNEL))
1298 				return __FAIL(ops, i);
1299 
1300 			/* Overlapping mappings */
1301 			if (!ops->map(ops, iova, iova + size, size,
1302 				      IOMMU_READ | IOMMU_NOEXEC, GFP_KERNEL))
1303 				return __FAIL(ops, i);
1304 
1305 			if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
1306 				return __FAIL(ops, i);
1307 
1308 			iova += SZ_1G;
1309 		}
1310 
1311 		/* Partial unmap */
1312 		size = 1UL << __ffs(cfg->pgsize_bitmap);
1313 		if (ops->unmap(ops, SZ_1G + size, size, NULL) != size)
1314 			return __FAIL(ops, i);
1315 
1316 		/* Remap of partial unmap */
1317 		if (ops->map(ops, SZ_1G + size, size, size, IOMMU_READ, GFP_KERNEL))
1318 			return __FAIL(ops, i);
1319 
1320 		if (ops->iova_to_phys(ops, SZ_1G + size + 42) != (size + 42))
1321 			return __FAIL(ops, i);
1322 
1323 		/* Full unmap */
1324 		iova = 0;
1325 		for_each_set_bit(j, &cfg->pgsize_bitmap, BITS_PER_LONG) {
1326 			size = 1UL << j;
1327 
1328 			if (ops->unmap(ops, iova, size, NULL) != size)
1329 				return __FAIL(ops, i);
1330 
1331 			if (ops->iova_to_phys(ops, iova + 42))
1332 				return __FAIL(ops, i);
1333 
1334 			/* Remap full block */
1335 			if (ops->map(ops, iova, iova, size, IOMMU_WRITE, GFP_KERNEL))
1336 				return __FAIL(ops, i);
1337 
1338 			if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
1339 				return __FAIL(ops, i);
1340 
1341 			iova += SZ_1G;
1342 		}
1343 
1344 		free_io_pgtable_ops(ops);
1345 	}
1346 
1347 	selftest_running = false;
1348 	return 0;
1349 }
1350 
arm_lpae_do_selftests(void)1351 static int __init arm_lpae_do_selftests(void)
1352 {
1353 	static const unsigned long pgsize[] __initconst = {
1354 		SZ_4K | SZ_2M | SZ_1G,
1355 		SZ_16K | SZ_32M,
1356 		SZ_64K | SZ_512M,
1357 	};
1358 
1359 	static const unsigned int ias[] __initconst = {
1360 		32, 36, 40, 42, 44, 48,
1361 	};
1362 
1363 	int i, j, pass = 0, fail = 0;
1364 	struct io_pgtable_cfg cfg = {
1365 		.tlb = &dummy_tlb_ops,
1366 		.oas = 48,
1367 		.coherent_walk = true,
1368 	};
1369 
1370 	for (i = 0; i < ARRAY_SIZE(pgsize); ++i) {
1371 		for (j = 0; j < ARRAY_SIZE(ias); ++j) {
1372 			cfg.pgsize_bitmap = pgsize[i];
1373 			cfg.ias = ias[j];
1374 			pr_info("selftest: pgsize_bitmap 0x%08lx, IAS %u\n",
1375 				pgsize[i], ias[j]);
1376 			if (arm_lpae_run_tests(&cfg))
1377 				fail++;
1378 			else
1379 				pass++;
1380 		}
1381 	}
1382 
1383 	pr_info("selftest: completed with %d PASS %d FAIL\n", pass, fail);
1384 	return fail ? -EFAULT : 0;
1385 }
1386 subsys_initcall(arm_lpae_do_selftests);
1387 #endif
1388