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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 #define ARM_LPAE_MAX_ADDR_BITS		52
24 #define ARM_LPAE_S2_MAX_CONCAT_PAGES	16
25 #define ARM_LPAE_MAX_LEVELS		4
26 
27 /* Struct accessors */
28 #define io_pgtable_to_data(x)						\
29 	container_of((x), struct arm_lpae_io_pgtable, iop)
30 
31 #define io_pgtable_ops_to_data(x)					\
32 	io_pgtable_to_data(io_pgtable_ops_to_pgtable(x))
33 
34 /*
35  * For consistency with the architecture, we always consider
36  * ARM_LPAE_MAX_LEVELS levels, with the walk starting at level n >=0
37  */
38 #define ARM_LPAE_START_LVL(d)		(ARM_LPAE_MAX_LEVELS - (d)->levels)
39 
40 /*
41  * Calculate the right shift amount to get to the portion describing level l
42  * in a virtual address mapped by the pagetable in d.
43  */
44 #define ARM_LPAE_LVL_SHIFT(l,d)						\
45 	((((d)->levels - ((l) - ARM_LPAE_START_LVL(d) + 1))		\
46 	  * (d)->bits_per_level) + (d)->pg_shift)
47 
48 #define ARM_LPAE_GRANULE(d)		(1UL << (d)->pg_shift)
49 
50 #define ARM_LPAE_PAGES_PER_PGD(d)					\
51 	DIV_ROUND_UP((d)->pgd_size, ARM_LPAE_GRANULE(d))
52 
53 /*
54  * Calculate the index at level l used to map virtual address a using the
55  * pagetable in d.
56  */
57 #define ARM_LPAE_PGD_IDX(l,d)						\
58 	((l) == ARM_LPAE_START_LVL(d) ? ilog2(ARM_LPAE_PAGES_PER_PGD(d)) : 0)
59 
60 #define ARM_LPAE_LVL_IDX(a,l,d)						\
61 	(((u64)(a) >> ARM_LPAE_LVL_SHIFT(l,d)) &			\
62 	 ((1 << ((d)->bits_per_level + ARM_LPAE_PGD_IDX(l,d))) - 1))
63 
64 /* Calculate the block/page mapping size at level l for pagetable in d. */
65 #define ARM_LPAE_BLOCK_SIZE(l,d)					\
66 	(1ULL << (ilog2(sizeof(arm_lpae_iopte)) +			\
67 		((ARM_LPAE_MAX_LEVELS - (l)) * (d)->bits_per_level)))
68 
69 /* Page table bits */
70 #define ARM_LPAE_PTE_TYPE_SHIFT		0
71 #define ARM_LPAE_PTE_TYPE_MASK		0x3
72 
73 #define ARM_LPAE_PTE_TYPE_BLOCK		1
74 #define ARM_LPAE_PTE_TYPE_TABLE		3
75 #define ARM_LPAE_PTE_TYPE_PAGE		3
76 
77 #define ARM_LPAE_PTE_ADDR_MASK		GENMASK_ULL(47,12)
78 
79 #define ARM_LPAE_PTE_NSTABLE		(((arm_lpae_iopte)1) << 63)
80 #define ARM_LPAE_PTE_XN			(((arm_lpae_iopte)3) << 53)
81 #define ARM_LPAE_PTE_AF			(((arm_lpae_iopte)1) << 10)
82 #define ARM_LPAE_PTE_SH_NS		(((arm_lpae_iopte)0) << 8)
83 #define ARM_LPAE_PTE_SH_OS		(((arm_lpae_iopte)2) << 8)
84 #define ARM_LPAE_PTE_SH_IS		(((arm_lpae_iopte)3) << 8)
85 #define ARM_LPAE_PTE_NS			(((arm_lpae_iopte)1) << 5)
86 #define ARM_LPAE_PTE_VALID		(((arm_lpae_iopte)1) << 0)
87 
88 #define ARM_LPAE_PTE_ATTR_LO_MASK	(((arm_lpae_iopte)0x3ff) << 2)
89 /* Ignore the contiguous bit for block splitting */
90 #define ARM_LPAE_PTE_ATTR_HI_MASK	(((arm_lpae_iopte)6) << 52)
91 #define ARM_LPAE_PTE_ATTR_MASK		(ARM_LPAE_PTE_ATTR_LO_MASK |	\
92 					 ARM_LPAE_PTE_ATTR_HI_MASK)
93 /* Software bit for solving coherency races */
94 #define ARM_LPAE_PTE_SW_SYNC		(((arm_lpae_iopte)1) << 55)
95 
96 /* Stage-1 PTE */
97 #define ARM_LPAE_PTE_AP_UNPRIV		(((arm_lpae_iopte)1) << 6)
98 #define ARM_LPAE_PTE_AP_RDONLY		(((arm_lpae_iopte)2) << 6)
99 #define ARM_LPAE_PTE_ATTRINDX_SHIFT	2
100 #define ARM_LPAE_PTE_nG			(((arm_lpae_iopte)1) << 11)
101 
102 /* Stage-2 PTE */
103 #define ARM_LPAE_PTE_HAP_FAULT		(((arm_lpae_iopte)0) << 6)
104 #define ARM_LPAE_PTE_HAP_READ		(((arm_lpae_iopte)1) << 6)
105 #define ARM_LPAE_PTE_HAP_WRITE		(((arm_lpae_iopte)2) << 6)
106 #define ARM_LPAE_PTE_MEMATTR_OIWB	(((arm_lpae_iopte)0xf) << 2)
107 #define ARM_LPAE_PTE_MEMATTR_NC		(((arm_lpae_iopte)0x5) << 2)
108 #define ARM_LPAE_PTE_MEMATTR_DEV	(((arm_lpae_iopte)0x1) << 2)
109 
110 /* Register bits */
111 #define ARM_32_LPAE_TCR_EAE		(1 << 31)
112 #define ARM_64_LPAE_S2_TCR_RES1		(1 << 31)
113 
114 #define ARM_LPAE_TCR_EPD1		(1 << 23)
115 
116 #define ARM_LPAE_TCR_TG0_4K		(0 << 14)
117 #define ARM_LPAE_TCR_TG0_64K		(1 << 14)
118 #define ARM_LPAE_TCR_TG0_16K		(2 << 14)
119 
120 #define ARM_LPAE_TCR_SH0_SHIFT		12
121 #define ARM_LPAE_TCR_SH0_MASK		0x3
122 #define ARM_LPAE_TCR_SH_NS		0
123 #define ARM_LPAE_TCR_SH_OS		2
124 #define ARM_LPAE_TCR_SH_IS		3
125 
126 #define ARM_LPAE_TCR_ORGN0_SHIFT	10
127 #define ARM_LPAE_TCR_IRGN0_SHIFT	8
128 #define ARM_LPAE_TCR_RGN_MASK		0x3
129 #define ARM_LPAE_TCR_RGN_NC		0
130 #define ARM_LPAE_TCR_RGN_WBWA		1
131 #define ARM_LPAE_TCR_RGN_WT		2
132 #define ARM_LPAE_TCR_RGN_WB		3
133 
134 #define ARM_LPAE_TCR_SL0_SHIFT		6
135 #define ARM_LPAE_TCR_SL0_MASK		0x3
136 
137 #define ARM_LPAE_TCR_T0SZ_SHIFT		0
138 #define ARM_LPAE_TCR_SZ_MASK		0xf
139 
140 #define ARM_LPAE_TCR_PS_SHIFT		16
141 #define ARM_LPAE_TCR_PS_MASK		0x7
142 
143 #define ARM_LPAE_TCR_IPS_SHIFT		32
144 #define ARM_LPAE_TCR_IPS_MASK		0x7
145 
146 #define ARM_LPAE_TCR_PS_32_BIT		0x0ULL
147 #define ARM_LPAE_TCR_PS_36_BIT		0x1ULL
148 #define ARM_LPAE_TCR_PS_40_BIT		0x2ULL
149 #define ARM_LPAE_TCR_PS_42_BIT		0x3ULL
150 #define ARM_LPAE_TCR_PS_44_BIT		0x4ULL
151 #define ARM_LPAE_TCR_PS_48_BIT		0x5ULL
152 #define ARM_LPAE_TCR_PS_52_BIT		0x6ULL
153 
154 #define ARM_LPAE_MAIR_ATTR_SHIFT(n)	((n) << 3)
155 #define ARM_LPAE_MAIR_ATTR_MASK		0xff
156 #define ARM_LPAE_MAIR_ATTR_DEVICE	0x04
157 #define ARM_LPAE_MAIR_ATTR_NC		0x44
158 #define ARM_LPAE_MAIR_ATTR_INC_OWBRWA	0xf4
159 #define ARM_LPAE_MAIR_ATTR_WBRWA	0xff
160 #define ARM_LPAE_MAIR_ATTR_IDX_NC	0
161 #define ARM_LPAE_MAIR_ATTR_IDX_CACHE	1
162 #define ARM_LPAE_MAIR_ATTR_IDX_DEV	2
163 #define ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE	3
164 
165 #define ARM_MALI_LPAE_TTBR_ADRMODE_TABLE (3u << 0)
166 #define ARM_MALI_LPAE_TTBR_READ_INNER	BIT(2)
167 #define ARM_MALI_LPAE_TTBR_SHARE_OUTER	BIT(4)
168 
169 #define ARM_MALI_LPAE_MEMATTR_IMP_DEF	0x88ULL
170 #define ARM_MALI_LPAE_MEMATTR_WRITE_ALLOC 0x8DULL
171 
172 /* IOPTE accessors */
173 #define iopte_deref(pte,d) __va(iopte_to_paddr(pte, d))
174 
175 #define iopte_type(pte,l)					\
176 	(((pte) >> ARM_LPAE_PTE_TYPE_SHIFT) & ARM_LPAE_PTE_TYPE_MASK)
177 
178 #define iopte_prot(pte)	((pte) & ARM_LPAE_PTE_ATTR_MASK)
179 
180 struct arm_lpae_io_pgtable {
181 	struct io_pgtable	iop;
182 
183 	int			levels;
184 	size_t			pgd_size;
185 	unsigned long		pg_shift;
186 	unsigned long		bits_per_level;
187 
188 	void			*pgd;
189 };
190 
191 typedef u64 arm_lpae_iopte;
192 
iopte_leaf(arm_lpae_iopte pte,int lvl,enum io_pgtable_fmt fmt)193 static inline bool iopte_leaf(arm_lpae_iopte pte, int lvl,
194 			      enum io_pgtable_fmt fmt)
195 {
196 	if (lvl == (ARM_LPAE_MAX_LEVELS - 1) && fmt != ARM_MALI_LPAE)
197 		return iopte_type(pte, lvl) == ARM_LPAE_PTE_TYPE_PAGE;
198 
199 	return iopte_type(pte, lvl) == ARM_LPAE_PTE_TYPE_BLOCK;
200 }
201 
paddr_to_iopte(phys_addr_t paddr,struct arm_lpae_io_pgtable * data)202 static arm_lpae_iopte paddr_to_iopte(phys_addr_t paddr,
203 				     struct arm_lpae_io_pgtable *data)
204 {
205 	arm_lpae_iopte pte = paddr;
206 
207 	/* Of the bits which overlap, either 51:48 or 15:12 are always RES0 */
208 	return (pte | (pte >> (48 - 12))) & ARM_LPAE_PTE_ADDR_MASK;
209 }
210 
iopte_to_paddr(arm_lpae_iopte pte,struct arm_lpae_io_pgtable * data)211 static phys_addr_t iopte_to_paddr(arm_lpae_iopte pte,
212 				  struct arm_lpae_io_pgtable *data)
213 {
214 	u64 paddr = pte & ARM_LPAE_PTE_ADDR_MASK;
215 
216 	if (data->pg_shift < 16)
217 		return paddr;
218 
219 	/* Rotate the packed high-order bits back to the top */
220 	return (paddr | (paddr << (48 - 12))) & (ARM_LPAE_PTE_ADDR_MASK << 4);
221 }
222 
223 static bool selftest_running = false;
224 
__arm_lpae_dma_addr(void * pages)225 static dma_addr_t __arm_lpae_dma_addr(void *pages)
226 {
227 	return (dma_addr_t)virt_to_phys(pages);
228 }
229 
__arm_lpae_alloc_pages(size_t size,gfp_t gfp,struct io_pgtable_cfg * cfg,void * cookie)230 static void *__arm_lpae_alloc_pages(size_t size, gfp_t gfp,
231 				    struct io_pgtable_cfg *cfg, void *cookie)
232 {
233 	struct device *dev = cfg->iommu_dev;
234 	int order = get_order(size);
235 	dma_addr_t dma;
236 	void *pages;
237 
238 	VM_BUG_ON((gfp & __GFP_HIGHMEM));
239 	pages = io_pgtable_alloc_pages(cfg, cookie, order, gfp | __GFP_ZERO);
240 	if (!pages)
241 		return NULL;
242 
243 	if (!cfg->coherent_walk) {
244 		dma = dma_map_single(dev, pages, size, DMA_TO_DEVICE);
245 		if (dma_mapping_error(dev, dma))
246 			goto out_free;
247 		/*
248 		 * We depend on the IOMMU being able to work with any physical
249 		 * address directly, so if the DMA layer suggests otherwise by
250 		 * translating or truncating them, that bodes very badly...
251 		 */
252 		if (dma != virt_to_phys(pages))
253 			goto out_unmap;
254 	}
255 
256 	return pages;
257 
258 out_unmap:
259 	dev_err(dev, "Cannot accommodate DMA translation for IOMMU page tables\n");
260 	dma_unmap_single(dev, dma, size, DMA_TO_DEVICE);
261 out_free:
262 	io_pgtable_free_pages(cfg, cookie, pages, order);
263 	return NULL;
264 }
265 
__arm_lpae_free_pages(void * pages,size_t size,struct io_pgtable_cfg * cfg,void * cookie)266 static void __arm_lpae_free_pages(void *pages, size_t size,
267 				  struct io_pgtable_cfg *cfg, void *cookie)
268 {
269 	if (!cfg->coherent_walk)
270 		dma_unmap_single(cfg->iommu_dev, __arm_lpae_dma_addr(pages),
271 				 size, DMA_TO_DEVICE);
272 	io_pgtable_free_pages(cfg, cookie, pages, get_order(size));
273 }
274 
__arm_lpae_sync_pte(arm_lpae_iopte * ptep,struct io_pgtable_cfg * cfg)275 static void __arm_lpae_sync_pte(arm_lpae_iopte *ptep,
276 				struct io_pgtable_cfg *cfg)
277 {
278 	dma_sync_single_for_device(cfg->iommu_dev, __arm_lpae_dma_addr(ptep),
279 				   sizeof(*ptep), DMA_TO_DEVICE);
280 }
281 
__arm_lpae_set_pte(arm_lpae_iopte * ptep,arm_lpae_iopte pte,struct io_pgtable_cfg * cfg)282 static void __arm_lpae_set_pte(arm_lpae_iopte *ptep, arm_lpae_iopte pte,
283 			       struct io_pgtable_cfg *cfg)
284 {
285 	*ptep = pte;
286 
287 	if (!cfg->coherent_walk)
288 		__arm_lpae_sync_pte(ptep, cfg);
289 }
290 
291 static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
292 			       struct iommu_iotlb_gather *gather,
293 			       unsigned long iova, size_t size, int lvl,
294 			       arm_lpae_iopte *ptep);
295 
__arm_lpae_init_pte(struct arm_lpae_io_pgtable * data,phys_addr_t paddr,arm_lpae_iopte prot,int lvl,arm_lpae_iopte * ptep)296 static void __arm_lpae_init_pte(struct arm_lpae_io_pgtable *data,
297 				phys_addr_t paddr, arm_lpae_iopte prot,
298 				int lvl, arm_lpae_iopte *ptep)
299 {
300 	arm_lpae_iopte pte = prot;
301 
302 	if (data->iop.cfg.quirks & IO_PGTABLE_QUIRK_ARM_NS)
303 		pte |= ARM_LPAE_PTE_NS;
304 
305 	if (data->iop.fmt != ARM_MALI_LPAE && lvl == ARM_LPAE_MAX_LEVELS - 1)
306 		pte |= ARM_LPAE_PTE_TYPE_PAGE;
307 	else
308 		pte |= ARM_LPAE_PTE_TYPE_BLOCK;
309 
310 	if (data->iop.fmt != ARM_MALI_LPAE)
311 		pte |= ARM_LPAE_PTE_AF;
312 	pte |= ARM_LPAE_PTE_SH_IS;
313 	pte |= paddr_to_iopte(paddr, data);
314 
315 	__arm_lpae_set_pte(ptep, pte, &data->iop.cfg);
316 }
317 
arm_lpae_init_pte(struct arm_lpae_io_pgtable * data,unsigned long iova,phys_addr_t paddr,arm_lpae_iopte prot,int lvl,arm_lpae_iopte * ptep)318 static int arm_lpae_init_pte(struct arm_lpae_io_pgtable *data,
319 			     unsigned long iova, phys_addr_t paddr,
320 			     arm_lpae_iopte prot, int lvl,
321 			     arm_lpae_iopte *ptep)
322 {
323 	arm_lpae_iopte pte = *ptep;
324 
325 	if (iopte_leaf(pte, lvl, data->iop.fmt)) {
326 		/* We require an unmap first */
327 		WARN_ON(!selftest_running);
328 		return -EEXIST;
329 	} else if (iopte_type(pte, lvl) == ARM_LPAE_PTE_TYPE_TABLE) {
330 		/*
331 		 * We need to unmap and free the old table before
332 		 * overwriting it with a block entry.
333 		 */
334 		arm_lpae_iopte *tblp;
335 		size_t sz = ARM_LPAE_BLOCK_SIZE(lvl, data);
336 
337 		tblp = ptep - ARM_LPAE_LVL_IDX(iova, lvl, data);
338 		if (__arm_lpae_unmap(data, NULL, iova, sz, lvl, tblp) != sz) {
339 			WARN_ON(1);
340 			return -EINVAL;
341 		}
342 	}
343 
344 	__arm_lpae_init_pte(data, paddr, prot, lvl, ptep);
345 	return 0;
346 }
347 
arm_lpae_install_table(arm_lpae_iopte * table,arm_lpae_iopte * ptep,arm_lpae_iopte curr,struct arm_lpae_io_pgtable * data)348 static arm_lpae_iopte arm_lpae_install_table(arm_lpae_iopte *table,
349 					     arm_lpae_iopte *ptep,
350 					     arm_lpae_iopte curr,
351 					     struct arm_lpae_io_pgtable *data)
352 {
353 	arm_lpae_iopte old, new;
354 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
355 
356 	new = paddr_to_iopte(__pa(table), data) | ARM_LPAE_PTE_TYPE_TABLE;
357 	if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS)
358 		new |= ARM_LPAE_PTE_NSTABLE;
359 
360 	/*
361 	 * Ensure the table itself is visible before its PTE can be.
362 	 * Whilst we could get away with cmpxchg64_release below, this
363 	 * doesn't have any ordering semantics when !CONFIG_SMP.
364 	 */
365 	dma_wmb();
366 
367 	old = cmpxchg64_relaxed(ptep, curr, new);
368 
369 	if (cfg->coherent_walk || (old & ARM_LPAE_PTE_SW_SYNC))
370 		return old;
371 
372 	/* Even if it's not ours, there's no point waiting; just kick it */
373 	__arm_lpae_sync_pte(ptep, cfg);
374 	if (old == curr)
375 		WRITE_ONCE(*ptep, new | ARM_LPAE_PTE_SW_SYNC);
376 
377 	return old;
378 }
379 
__arm_lpae_map(struct arm_lpae_io_pgtable * data,unsigned long iova,phys_addr_t paddr,size_t size,arm_lpae_iopte prot,int lvl,arm_lpae_iopte * ptep)380 static int __arm_lpae_map(struct arm_lpae_io_pgtable *data, unsigned long iova,
381 			  phys_addr_t paddr, size_t size, arm_lpae_iopte prot,
382 			  int lvl, arm_lpae_iopte *ptep)
383 {
384 	arm_lpae_iopte *cptep, pte;
385 	size_t block_size = ARM_LPAE_BLOCK_SIZE(lvl, data);
386 	size_t tblsz = ARM_LPAE_GRANULE(data);
387 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
388 	void *cookie = data->iop.cookie;
389 
390 	/* Find our entry at the current level */
391 	ptep += ARM_LPAE_LVL_IDX(iova, lvl, data);
392 
393 	/* If we can install a leaf entry at this level, then do so */
394 	if (size == block_size && (size & cfg->pgsize_bitmap))
395 		return arm_lpae_init_pte(data, iova, paddr, prot, lvl, ptep);
396 
397 	/* We can't allocate tables at the final level */
398 	if (WARN_ON(lvl >= ARM_LPAE_MAX_LEVELS - 1))
399 		return -EINVAL;
400 
401 	/* Grab a pointer to the next level */
402 	pte = READ_ONCE(*ptep);
403 	if (!pte) {
404 		cptep = __arm_lpae_alloc_pages(tblsz, GFP_ATOMIC, cfg, cookie);
405 		if (!cptep)
406 			return -ENOMEM;
407 
408 		pte = arm_lpae_install_table(cptep, ptep, 0, data);
409 		if (pte)
410 			__arm_lpae_free_pages(cptep, tblsz, cfg, cookie);
411 	} else if (!cfg->coherent_walk && !(pte & ARM_LPAE_PTE_SW_SYNC)) {
412 		__arm_lpae_sync_pte(ptep, cfg);
413 	}
414 
415 	if (pte && !iopte_leaf(pte, lvl, data->iop.fmt)) {
416 		cptep = iopte_deref(pte, data);
417 	} else if (pte) {
418 		/* We require an unmap first */
419 		WARN_ON(!selftest_running);
420 		return -EEXIST;
421 	}
422 
423 	/* Rinse, repeat */
424 	return __arm_lpae_map(data, iova, paddr, size, prot, lvl + 1, cptep);
425 }
426 
arm_lpae_prot_to_pte(struct arm_lpae_io_pgtable * data,int prot)427 static arm_lpae_iopte arm_lpae_prot_to_pte(struct arm_lpae_io_pgtable *data,
428 					   int prot)
429 {
430 	arm_lpae_iopte pte;
431 
432 	if (data->iop.fmt == ARM_64_LPAE_S1 ||
433 	    data->iop.fmt == ARM_32_LPAE_S1) {
434 		pte = ARM_LPAE_PTE_nG;
435 		if (!(prot & IOMMU_WRITE) && (prot & IOMMU_READ))
436 			pte |= ARM_LPAE_PTE_AP_RDONLY;
437 		if (!(prot & IOMMU_PRIV))
438 			pte |= ARM_LPAE_PTE_AP_UNPRIV;
439 	} else {
440 		pte = ARM_LPAE_PTE_HAP_FAULT;
441 		if (prot & IOMMU_READ)
442 			pte |= ARM_LPAE_PTE_HAP_READ;
443 		if (prot & IOMMU_WRITE)
444 			pte |= ARM_LPAE_PTE_HAP_WRITE;
445 	}
446 
447 	/*
448 	 * Note that this logic is structured to accommodate Mali LPAE
449 	 * having stage-1-like attributes but stage-2-like permissions.
450 	 */
451 	if (data->iop.fmt == ARM_64_LPAE_S2 ||
452 	    data->iop.fmt == ARM_32_LPAE_S2) {
453 		if (prot & IOMMU_MMIO)
454 			pte |= ARM_LPAE_PTE_MEMATTR_DEV;
455 		else if (prot & IOMMU_CACHE)
456 			pte |= ARM_LPAE_PTE_MEMATTR_OIWB;
457 		else
458 			pte |= ARM_LPAE_PTE_MEMATTR_NC;
459 	} else {
460 		if (prot & IOMMU_MMIO)
461 			pte |= (ARM_LPAE_MAIR_ATTR_IDX_DEV
462 				<< ARM_LPAE_PTE_ATTRINDX_SHIFT);
463 		else if (prot & IOMMU_CACHE)
464 			pte |= (ARM_LPAE_MAIR_ATTR_IDX_CACHE
465 				<< ARM_LPAE_PTE_ATTRINDX_SHIFT);
466 		else if (prot & IOMMU_QCOM_SYS_CACHE)
467 			pte |= (ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE
468 				<< ARM_LPAE_PTE_ATTRINDX_SHIFT);
469 	}
470 
471 	if (prot & IOMMU_NOEXEC)
472 		pte |= ARM_LPAE_PTE_XN;
473 
474 	return pte;
475 }
476 
arm_lpae_map(struct io_pgtable_ops * ops,unsigned long iova,phys_addr_t paddr,size_t size,int iommu_prot)477 static int arm_lpae_map(struct io_pgtable_ops *ops, unsigned long iova,
478 			phys_addr_t paddr, size_t size, int iommu_prot)
479 {
480 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
481 	arm_lpae_iopte *ptep = data->pgd;
482 	int ret, lvl = ARM_LPAE_START_LVL(data);
483 	arm_lpae_iopte prot;
484 
485 	/* If no access, then nothing to do */
486 	if (!(iommu_prot & (IOMMU_READ | IOMMU_WRITE)))
487 		return 0;
488 
489 	if (WARN_ON(iova >= (1ULL << data->iop.cfg.ias) ||
490 		    paddr >= (1ULL << data->iop.cfg.oas)))
491 		return -ERANGE;
492 
493 	prot = arm_lpae_prot_to_pte(data, iommu_prot);
494 	ret = __arm_lpae_map(data, iova, paddr, size, prot, lvl, ptep);
495 	/*
496 	 * Synchronise all PTE updates for the new mapping before there's
497 	 * a chance for anything to kick off a table walk for the new iova.
498 	 */
499 	wmb();
500 
501 	return ret;
502 }
503 
__arm_lpae_free_pgtable(struct arm_lpae_io_pgtable * data,int lvl,arm_lpae_iopte * ptep)504 static void __arm_lpae_free_pgtable(struct arm_lpae_io_pgtable *data, int lvl,
505 				    arm_lpae_iopte *ptep)
506 {
507 	arm_lpae_iopte *start, *end;
508 	unsigned long table_size;
509 	void *cookie = data->iop.cookie;
510 
511 	if (lvl == ARM_LPAE_START_LVL(data))
512 		table_size = data->pgd_size;
513 	else
514 		table_size = ARM_LPAE_GRANULE(data);
515 
516 	start = ptep;
517 
518 	/* Only leaf entries at the last level */
519 	if (lvl == ARM_LPAE_MAX_LEVELS - 1)
520 		end = ptep;
521 	else
522 		end = (void *)ptep + table_size;
523 
524 	while (ptep != end) {
525 		arm_lpae_iopte pte = *ptep++;
526 
527 		if (!pte || iopte_leaf(pte, lvl, data->iop.fmt))
528 			continue;
529 
530 		__arm_lpae_free_pgtable(data, lvl + 1, iopte_deref(pte, data));
531 	}
532 
533 	__arm_lpae_free_pages(start, table_size, &data->iop.cfg, cookie);
534 }
535 
arm_lpae_free_pgtable(struct io_pgtable * iop)536 static void arm_lpae_free_pgtable(struct io_pgtable *iop)
537 {
538 	struct arm_lpae_io_pgtable *data = io_pgtable_to_data(iop);
539 
540 	__arm_lpae_free_pgtable(data, ARM_LPAE_START_LVL(data), data->pgd);
541 	kfree(data);
542 }
543 
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)544 static size_t arm_lpae_split_blk_unmap(struct arm_lpae_io_pgtable *data,
545 				       struct iommu_iotlb_gather *gather,
546 				       unsigned long iova, size_t size,
547 				       arm_lpae_iopte blk_pte, int lvl,
548 				       arm_lpae_iopte *ptep)
549 {
550 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
551 	arm_lpae_iopte pte, *tablep;
552 	phys_addr_t blk_paddr;
553 	size_t tablesz = ARM_LPAE_GRANULE(data);
554 	size_t split_sz = ARM_LPAE_BLOCK_SIZE(lvl, data);
555 	int i, unmap_idx = -1;
556 	void *cookie = data->iop.cookie;
557 
558 	if (WARN_ON(lvl == ARM_LPAE_MAX_LEVELS))
559 		return 0;
560 
561 	tablep = __arm_lpae_alloc_pages(tablesz, GFP_ATOMIC, cfg, cookie);
562 	if (!tablep)
563 		return 0; /* Bytes unmapped */
564 
565 	if (size == split_sz)
566 		unmap_idx = ARM_LPAE_LVL_IDX(iova, lvl, data);
567 
568 	blk_paddr = iopte_to_paddr(blk_pte, data);
569 	pte = iopte_prot(blk_pte);
570 
571 	for (i = 0; i < tablesz / sizeof(pte); i++, blk_paddr += split_sz) {
572 		/* Unmap! */
573 		if (i == unmap_idx)
574 			continue;
575 
576 		__arm_lpae_init_pte(data, blk_paddr, pte, lvl, &tablep[i]);
577 	}
578 
579 	pte = arm_lpae_install_table(tablep, ptep, blk_pte, data);
580 	if (pte != blk_pte) {
581 		__arm_lpae_free_pages(tablep, tablesz, cfg, cookie);
582 		/*
583 		 * We may race against someone unmapping another part of this
584 		 * block, but anything else is invalid. We can't misinterpret
585 		 * a page entry here since we're never at the last level.
586 		 */
587 		if (iopte_type(pte, lvl - 1) != ARM_LPAE_PTE_TYPE_TABLE)
588 			return 0;
589 
590 		tablep = iopte_deref(pte, data);
591 	} else if (unmap_idx >= 0) {
592 		io_pgtable_tlb_add_page(&data->iop, gather, iova, size);
593 		return size;
594 	}
595 
596 	return __arm_lpae_unmap(data, gather, iova, size, lvl, tablep);
597 }
598 
__arm_lpae_unmap(struct arm_lpae_io_pgtable * data,struct iommu_iotlb_gather * gather,unsigned long iova,size_t size,int lvl,arm_lpae_iopte * ptep)599 static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
600 			       struct iommu_iotlb_gather *gather,
601 			       unsigned long iova, size_t size, int lvl,
602 			       arm_lpae_iopte *ptep)
603 {
604 	arm_lpae_iopte pte;
605 	struct io_pgtable *iop = &data->iop;
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 	ptep += ARM_LPAE_LVL_IDX(iova, lvl, data);
612 	pte = READ_ONCE(*ptep);
613 	if (WARN_ON(!pte))
614 		return 0;
615 
616 	/* If the size matches this level, we're in the right place */
617 	if (size == ARM_LPAE_BLOCK_SIZE(lvl, data)) {
618 		__arm_lpae_set_pte(ptep, 0, &iop->cfg);
619 
620 		if (!iopte_leaf(pte, lvl, iop->fmt)) {
621 			/* Also flush any partial walks */
622 			io_pgtable_tlb_flush_walk(iop, iova, size,
623 						  ARM_LPAE_GRANULE(data));
624 			ptep = iopte_deref(pte, data);
625 			__arm_lpae_free_pgtable(data, lvl + 1, ptep);
626 		} else if (iop->cfg.quirks & IO_PGTABLE_QUIRK_NON_STRICT) {
627 			/*
628 			 * Order the PTE update against queueing the IOVA, to
629 			 * guarantee that a flush callback from a different CPU
630 			 * has observed it before the TLBIALL can be issued.
631 			 */
632 			smp_wmb();
633 		} else {
634 			io_pgtable_tlb_add_page(iop, gather, iova, size);
635 		}
636 
637 		return size;
638 	} else if (iopte_leaf(pte, lvl, iop->fmt)) {
639 		/*
640 		 * Insert a table at the next level to map the old region,
641 		 * minus the part we want to unmap
642 		 */
643 		return arm_lpae_split_blk_unmap(data, gather, iova, size, pte,
644 						lvl + 1, ptep);
645 	}
646 
647 	/* Keep on walkin' */
648 	ptep = iopte_deref(pte, data);
649 	return __arm_lpae_unmap(data, gather, iova, size, lvl + 1, ptep);
650 }
651 
arm_lpae_unmap(struct io_pgtable_ops * ops,unsigned long iova,size_t size,struct iommu_iotlb_gather * gather)652 static size_t arm_lpae_unmap(struct io_pgtable_ops *ops, unsigned long iova,
653 			     size_t size, struct iommu_iotlb_gather *gather)
654 {
655 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
656 	arm_lpae_iopte *ptep = data->pgd;
657 	int lvl = ARM_LPAE_START_LVL(data);
658 
659 	if (WARN_ON(iova >= (1ULL << data->iop.cfg.ias)))
660 		return 0;
661 
662 	return __arm_lpae_unmap(data, gather, iova, size, lvl, ptep);
663 }
664 
arm_lpae_iova_to_phys(struct io_pgtable_ops * ops,unsigned long iova)665 static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops,
666 					 unsigned long iova)
667 {
668 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
669 	arm_lpae_iopte pte, *ptep = data->pgd;
670 	int lvl = ARM_LPAE_START_LVL(data);
671 
672 	do {
673 		/* Valid IOPTE pointer? */
674 		if (!ptep)
675 			return 0;
676 
677 		/* Grab the IOPTE we're interested in */
678 		ptep += ARM_LPAE_LVL_IDX(iova, lvl, data);
679 		pte = READ_ONCE(*ptep);
680 
681 		/* Valid entry? */
682 		if (!pte)
683 			return 0;
684 
685 		/* Leaf entry? */
686 		if (iopte_leaf(pte, lvl, data->iop.fmt))
687 			goto found_translation;
688 
689 		/* Take it to the next level */
690 		ptep = iopte_deref(pte, data);
691 	} while (++lvl < ARM_LPAE_MAX_LEVELS);
692 
693 	/* Ran out of page tables to walk */
694 	return 0;
695 
696 found_translation:
697 	iova &= (ARM_LPAE_BLOCK_SIZE(lvl, data) - 1);
698 	return iopte_to_paddr(pte, data) | iova;
699 }
700 
arm_lpae_restrict_pgsizes(struct io_pgtable_cfg * cfg)701 static void arm_lpae_restrict_pgsizes(struct io_pgtable_cfg *cfg)
702 {
703 	unsigned long granule, page_sizes;
704 	unsigned int max_addr_bits = 48;
705 
706 	/*
707 	 * We need to restrict the supported page sizes to match the
708 	 * translation regime for a particular granule. Aim to match
709 	 * the CPU page size if possible, otherwise prefer smaller sizes.
710 	 * While we're at it, restrict the block sizes to match the
711 	 * chosen granule.
712 	 */
713 	if (cfg->pgsize_bitmap & PAGE_SIZE)
714 		granule = PAGE_SIZE;
715 	else if (cfg->pgsize_bitmap & ~PAGE_MASK)
716 		granule = 1UL << __fls(cfg->pgsize_bitmap & ~PAGE_MASK);
717 	else if (cfg->pgsize_bitmap & PAGE_MASK)
718 		granule = 1UL << __ffs(cfg->pgsize_bitmap & PAGE_MASK);
719 	else
720 		granule = 0;
721 
722 	switch (granule) {
723 	case SZ_4K:
724 		page_sizes = (SZ_4K | SZ_2M | SZ_1G);
725 		break;
726 	case SZ_16K:
727 		page_sizes = (SZ_16K | SZ_32M);
728 		break;
729 	case SZ_64K:
730 		max_addr_bits = 52;
731 		page_sizes = (SZ_64K | SZ_512M);
732 		if (cfg->oas > 48)
733 			page_sizes |= 1ULL << 42; /* 4TB */
734 		break;
735 	default:
736 		page_sizes = 0;
737 	}
738 
739 	cfg->pgsize_bitmap &= page_sizes;
740 	cfg->ias = min(cfg->ias, max_addr_bits);
741 	cfg->oas = min(cfg->oas, max_addr_bits);
742 }
743 
744 static struct arm_lpae_io_pgtable *
arm_lpae_alloc_pgtable(struct io_pgtable_cfg * cfg)745 arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg)
746 {
747 	unsigned long va_bits, pgd_bits;
748 	struct arm_lpae_io_pgtable *data;
749 
750 	arm_lpae_restrict_pgsizes(cfg);
751 
752 	if (!(cfg->pgsize_bitmap & (SZ_4K | SZ_16K | SZ_64K)))
753 		return NULL;
754 
755 	if (cfg->ias > ARM_LPAE_MAX_ADDR_BITS)
756 		return NULL;
757 
758 	if (cfg->oas > ARM_LPAE_MAX_ADDR_BITS)
759 		return NULL;
760 
761 	if (!selftest_running && cfg->iommu_dev->dma_pfn_offset) {
762 		dev_err(cfg->iommu_dev, "Cannot accommodate DMA offset for IOMMU page tables\n");
763 		return NULL;
764 	}
765 
766 	data = kmalloc(sizeof(*data), GFP_KERNEL);
767 	if (!data)
768 		return NULL;
769 
770 	data->pg_shift = __ffs(cfg->pgsize_bitmap);
771 	data->bits_per_level = data->pg_shift - ilog2(sizeof(arm_lpae_iopte));
772 
773 	va_bits = cfg->ias - data->pg_shift;
774 	data->levels = DIV_ROUND_UP(va_bits, data->bits_per_level);
775 
776 	/* Calculate the actual size of our pgd (without concatenation) */
777 	pgd_bits = va_bits - (data->bits_per_level * (data->levels - 1));
778 	data->pgd_size = 1UL << (pgd_bits + ilog2(sizeof(arm_lpae_iopte)));
779 
780 	data->iop.ops = (struct io_pgtable_ops) {
781 		.map		= arm_lpae_map,
782 		.unmap		= arm_lpae_unmap,
783 		.iova_to_phys	= arm_lpae_iova_to_phys,
784 	};
785 
786 	return data;
787 }
788 
789 static struct io_pgtable *
arm_64_lpae_alloc_pgtable_s1(struct io_pgtable_cfg * cfg,void * cookie)790 arm_64_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie)
791 {
792 	u64 reg;
793 	struct arm_lpae_io_pgtable *data;
794 
795 	if (cfg->quirks & ~(IO_PGTABLE_QUIRK_ARM_NS |
796 			    IO_PGTABLE_QUIRK_NON_STRICT))
797 		return NULL;
798 
799 	data = arm_lpae_alloc_pgtable(cfg);
800 	if (!data)
801 		return NULL;
802 
803 	/* TCR */
804 	if (cfg->coherent_walk) {
805 		reg = (ARM_LPAE_TCR_SH_IS << ARM_LPAE_TCR_SH0_SHIFT) |
806 		      (ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_IRGN0_SHIFT) |
807 		      (ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_ORGN0_SHIFT);
808 	} else {
809 		reg = (ARM_LPAE_TCR_SH_OS << ARM_LPAE_TCR_SH0_SHIFT) |
810 		      (ARM_LPAE_TCR_RGN_NC << ARM_LPAE_TCR_IRGN0_SHIFT) |
811 		      (ARM_LPAE_TCR_RGN_NC << ARM_LPAE_TCR_ORGN0_SHIFT);
812 	}
813 
814 	switch (ARM_LPAE_GRANULE(data)) {
815 	case SZ_4K:
816 		reg |= ARM_LPAE_TCR_TG0_4K;
817 		break;
818 	case SZ_16K:
819 		reg |= ARM_LPAE_TCR_TG0_16K;
820 		break;
821 	case SZ_64K:
822 		reg |= ARM_LPAE_TCR_TG0_64K;
823 		break;
824 	}
825 
826 	switch (cfg->oas) {
827 	case 32:
828 		reg |= (ARM_LPAE_TCR_PS_32_BIT << ARM_LPAE_TCR_IPS_SHIFT);
829 		break;
830 	case 36:
831 		reg |= (ARM_LPAE_TCR_PS_36_BIT << ARM_LPAE_TCR_IPS_SHIFT);
832 		break;
833 	case 40:
834 		reg |= (ARM_LPAE_TCR_PS_40_BIT << ARM_LPAE_TCR_IPS_SHIFT);
835 		break;
836 	case 42:
837 		reg |= (ARM_LPAE_TCR_PS_42_BIT << ARM_LPAE_TCR_IPS_SHIFT);
838 		break;
839 	case 44:
840 		reg |= (ARM_LPAE_TCR_PS_44_BIT << ARM_LPAE_TCR_IPS_SHIFT);
841 		break;
842 	case 48:
843 		reg |= (ARM_LPAE_TCR_PS_48_BIT << ARM_LPAE_TCR_IPS_SHIFT);
844 		break;
845 	case 52:
846 		reg |= (ARM_LPAE_TCR_PS_52_BIT << ARM_LPAE_TCR_IPS_SHIFT);
847 		break;
848 	default:
849 		goto out_free_data;
850 	}
851 
852 	reg |= (64ULL - cfg->ias) << ARM_LPAE_TCR_T0SZ_SHIFT;
853 
854 	/* Disable speculative walks through TTBR1 */
855 	reg |= ARM_LPAE_TCR_EPD1;
856 	cfg->arm_lpae_s1_cfg.tcr = reg;
857 
858 	/* MAIRs */
859 	reg = (ARM_LPAE_MAIR_ATTR_NC
860 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_NC)) |
861 	      (ARM_LPAE_MAIR_ATTR_WBRWA
862 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_CACHE)) |
863 	      (ARM_LPAE_MAIR_ATTR_DEVICE
864 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_DEV)) |
865 	      (ARM_LPAE_MAIR_ATTR_INC_OWBRWA
866 	       << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_INC_OCACHE));
867 
868 	cfg->arm_lpae_s1_cfg.mair[0] = reg;
869 	cfg->arm_lpae_s1_cfg.mair[1] = 0;
870 
871 	/* Looking good; allocate a pgd */
872 	data->pgd = __arm_lpae_alloc_pages(data->pgd_size, GFP_KERNEL, cfg,
873 					   cookie);
874 	if (!data->pgd)
875 		goto out_free_data;
876 
877 	/* Ensure the empty pgd is visible before any actual TTBR write */
878 	wmb();
879 
880 	/* TTBRs */
881 	cfg->arm_lpae_s1_cfg.ttbr[0] = virt_to_phys(data->pgd);
882 	cfg->arm_lpae_s1_cfg.ttbr[1] = 0;
883 	return &data->iop;
884 
885 out_free_data:
886 	kfree(data);
887 	return NULL;
888 }
889 
890 static struct io_pgtable *
arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg * cfg,void * cookie)891 arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
892 {
893 	u64 reg, sl;
894 	struct arm_lpae_io_pgtable *data;
895 
896 	/* The NS quirk doesn't apply at stage 2 */
897 	if (cfg->quirks & ~(IO_PGTABLE_QUIRK_NON_STRICT))
898 		return NULL;
899 
900 	data = arm_lpae_alloc_pgtable(cfg);
901 	if (!data)
902 		return NULL;
903 
904 	/*
905 	 * Concatenate PGDs at level 1 if possible in order to reduce
906 	 * the depth of the stage-2 walk.
907 	 */
908 	if (data->levels == ARM_LPAE_MAX_LEVELS) {
909 		unsigned long pgd_pages;
910 
911 		pgd_pages = data->pgd_size >> ilog2(sizeof(arm_lpae_iopte));
912 		if (pgd_pages <= ARM_LPAE_S2_MAX_CONCAT_PAGES) {
913 			data->pgd_size = pgd_pages << data->pg_shift;
914 			data->levels--;
915 		}
916 	}
917 
918 	/* VTCR */
919 	reg = ARM_64_LPAE_S2_TCR_RES1 |
920 	     (ARM_LPAE_TCR_SH_IS << ARM_LPAE_TCR_SH0_SHIFT) |
921 	     (ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_IRGN0_SHIFT) |
922 	     (ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_ORGN0_SHIFT);
923 
924 	sl = ARM_LPAE_START_LVL(data);
925 
926 	switch (ARM_LPAE_GRANULE(data)) {
927 	case SZ_4K:
928 		reg |= ARM_LPAE_TCR_TG0_4K;
929 		sl++; /* SL0 format is different for 4K granule size */
930 		break;
931 	case SZ_16K:
932 		reg |= ARM_LPAE_TCR_TG0_16K;
933 		break;
934 	case SZ_64K:
935 		reg |= ARM_LPAE_TCR_TG0_64K;
936 		break;
937 	}
938 
939 	switch (cfg->oas) {
940 	case 32:
941 		reg |= (ARM_LPAE_TCR_PS_32_BIT << ARM_LPAE_TCR_PS_SHIFT);
942 		break;
943 	case 36:
944 		reg |= (ARM_LPAE_TCR_PS_36_BIT << ARM_LPAE_TCR_PS_SHIFT);
945 		break;
946 	case 40:
947 		reg |= (ARM_LPAE_TCR_PS_40_BIT << ARM_LPAE_TCR_PS_SHIFT);
948 		break;
949 	case 42:
950 		reg |= (ARM_LPAE_TCR_PS_42_BIT << ARM_LPAE_TCR_PS_SHIFT);
951 		break;
952 	case 44:
953 		reg |= (ARM_LPAE_TCR_PS_44_BIT << ARM_LPAE_TCR_PS_SHIFT);
954 		break;
955 	case 48:
956 		reg |= (ARM_LPAE_TCR_PS_48_BIT << ARM_LPAE_TCR_PS_SHIFT);
957 		break;
958 	case 52:
959 		reg |= (ARM_LPAE_TCR_PS_52_BIT << ARM_LPAE_TCR_PS_SHIFT);
960 		break;
961 	default:
962 		goto out_free_data;
963 	}
964 
965 	reg |= (64ULL - cfg->ias) << ARM_LPAE_TCR_T0SZ_SHIFT;
966 	reg |= (~sl & ARM_LPAE_TCR_SL0_MASK) << ARM_LPAE_TCR_SL0_SHIFT;
967 	cfg->arm_lpae_s2_cfg.vtcr = reg;
968 
969 	/* Allocate pgd pages */
970 	data->pgd = __arm_lpae_alloc_pages(data->pgd_size, GFP_KERNEL, cfg,
971 					   cookie);
972 	if (!data->pgd)
973 		goto out_free_data;
974 
975 	/* Ensure the empty pgd is visible before any actual TTBR write */
976 	wmb();
977 
978 	/* VTTBR */
979 	cfg->arm_lpae_s2_cfg.vttbr = virt_to_phys(data->pgd);
980 	return &data->iop;
981 
982 out_free_data:
983 	kfree(data);
984 	return NULL;
985 }
986 
987 static struct io_pgtable *
arm_32_lpae_alloc_pgtable_s1(struct io_pgtable_cfg * cfg,void * cookie)988 arm_32_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie)
989 {
990 	struct io_pgtable *iop;
991 
992 	if (cfg->ias > 32 || cfg->oas > 40)
993 		return NULL;
994 
995 	cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
996 	iop = arm_64_lpae_alloc_pgtable_s1(cfg, cookie);
997 	if (iop) {
998 		cfg->arm_lpae_s1_cfg.tcr |= ARM_32_LPAE_TCR_EAE;
999 		cfg->arm_lpae_s1_cfg.tcr &= 0xffffffff;
1000 	}
1001 
1002 	return iop;
1003 }
1004 
1005 static struct io_pgtable *
arm_32_lpae_alloc_pgtable_s2(struct io_pgtable_cfg * cfg,void * cookie)1006 arm_32_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
1007 {
1008 	struct io_pgtable *iop;
1009 
1010 	if (cfg->ias > 40 || cfg->oas > 40)
1011 		return NULL;
1012 
1013 	cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
1014 	iop = arm_64_lpae_alloc_pgtable_s2(cfg, cookie);
1015 	if (iop)
1016 		cfg->arm_lpae_s2_cfg.vtcr &= 0xffffffff;
1017 
1018 	return iop;
1019 }
1020 
1021 static struct io_pgtable *
arm_mali_lpae_alloc_pgtable(struct io_pgtable_cfg * cfg,void * cookie)1022 arm_mali_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)
1023 {
1024 	struct arm_lpae_io_pgtable *data;
1025 
1026 	/* No quirks for Mali (hopefully) */
1027 	if (cfg->quirks)
1028 		return NULL;
1029 
1030 	if (cfg->ias > 48 || cfg->oas > 40)
1031 		return NULL;
1032 
1033 	cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
1034 
1035 	data = arm_lpae_alloc_pgtable(cfg);
1036 	if (!data)
1037 		return NULL;
1038 
1039 	/* Mali seems to need a full 4-level table regardless of IAS */
1040 	if (data->levels < ARM_LPAE_MAX_LEVELS) {
1041 		data->levels = ARM_LPAE_MAX_LEVELS;
1042 		data->pgd_size = sizeof(arm_lpae_iopte);
1043 	}
1044 	/*
1045 	 * MEMATTR: Mali has no actual notion of a non-cacheable type, so the
1046 	 * best we can do is mimic the out-of-tree driver and hope that the
1047 	 * "implementation-defined caching policy" is good enough. Similarly,
1048 	 * we'll use it for the sake of a valid attribute for our 'device'
1049 	 * index, although callers should never request that in practice.
1050 	 */
1051 	cfg->arm_mali_lpae_cfg.memattr =
1052 		(ARM_MALI_LPAE_MEMATTR_IMP_DEF
1053 		 << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_NC)) |
1054 		(ARM_MALI_LPAE_MEMATTR_WRITE_ALLOC
1055 		 << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_CACHE)) |
1056 		(ARM_MALI_LPAE_MEMATTR_IMP_DEF
1057 		 << ARM_LPAE_MAIR_ATTR_SHIFT(ARM_LPAE_MAIR_ATTR_IDX_DEV));
1058 
1059 	data->pgd = __arm_lpae_alloc_pages(data->pgd_size, GFP_KERNEL, cfg,
1060 					   cookie);
1061 	if (!data->pgd)
1062 		goto out_free_data;
1063 
1064 	/* Ensure the empty pgd is visible before TRANSTAB can be written */
1065 	wmb();
1066 
1067 	cfg->arm_mali_lpae_cfg.transtab = virt_to_phys(data->pgd) |
1068 					  ARM_MALI_LPAE_TTBR_READ_INNER |
1069 					  ARM_MALI_LPAE_TTBR_ADRMODE_TABLE;
1070 	return &data->iop;
1071 
1072 out_free_data:
1073 	kfree(data);
1074 	return NULL;
1075 }
1076 
1077 struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns = {
1078 	.alloc	= arm_64_lpae_alloc_pgtable_s1,
1079 	.free	= arm_lpae_free_pgtable,
1080 };
1081 
1082 struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns = {
1083 	.alloc	= arm_64_lpae_alloc_pgtable_s2,
1084 	.free	= arm_lpae_free_pgtable,
1085 };
1086 
1087 struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns = {
1088 	.alloc	= arm_32_lpae_alloc_pgtable_s1,
1089 	.free	= arm_lpae_free_pgtable,
1090 };
1091 
1092 struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns = {
1093 	.alloc	= arm_32_lpae_alloc_pgtable_s2,
1094 	.free	= arm_lpae_free_pgtable,
1095 };
1096 
1097 struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns = {
1098 	.alloc	= arm_mali_lpae_alloc_pgtable,
1099 	.free	= arm_lpae_free_pgtable,
1100 };
1101 
1102 #ifdef CONFIG_IOMMU_IO_PGTABLE_LPAE_SELFTEST
1103 
1104 static struct io_pgtable_cfg *cfg_cookie;
1105 
dummy_tlb_flush_all(void * cookie)1106 static void dummy_tlb_flush_all(void *cookie)
1107 {
1108 	WARN_ON(cookie != cfg_cookie);
1109 }
1110 
dummy_tlb_flush(unsigned long iova,size_t size,size_t granule,void * cookie)1111 static void dummy_tlb_flush(unsigned long iova, size_t size, size_t granule,
1112 			    void *cookie)
1113 {
1114 	WARN_ON(cookie != cfg_cookie);
1115 	WARN_ON(!(size & cfg_cookie->pgsize_bitmap));
1116 }
1117 
dummy_tlb_add_page(struct iommu_iotlb_gather * gather,unsigned long iova,size_t granule,void * cookie)1118 static void dummy_tlb_add_page(struct iommu_iotlb_gather *gather,
1119 			       unsigned long iova, size_t granule, void *cookie)
1120 {
1121 	dummy_tlb_flush(iova, granule, granule, cookie);
1122 }
1123 
1124 static const struct iommu_flush_ops dummy_tlb_ops __initconst = {
1125 	.tlb_flush_all	= dummy_tlb_flush_all,
1126 	.tlb_flush_walk	= dummy_tlb_flush,
1127 	.tlb_flush_leaf	= dummy_tlb_flush,
1128 	.tlb_add_page	= dummy_tlb_add_page,
1129 };
1130 
arm_lpae_dump_ops(struct io_pgtable_ops * ops)1131 static void __init arm_lpae_dump_ops(struct io_pgtable_ops *ops)
1132 {
1133 	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
1134 	struct io_pgtable_cfg *cfg = &data->iop.cfg;
1135 
1136 	pr_err("cfg: pgsize_bitmap 0x%lx, ias %u-bit\n",
1137 		cfg->pgsize_bitmap, cfg->ias);
1138 	pr_err("data: %d levels, 0x%zx pgd_size, %lu pg_shift, %lu bits_per_level, pgd @ %p\n",
1139 		data->levels, data->pgd_size, data->pg_shift,
1140 		data->bits_per_level, data->pgd);
1141 }
1142 
1143 #define __FAIL(ops, i)	({						\
1144 		WARN(1, "selftest: test failed for fmt idx %d\n", (i));	\
1145 		arm_lpae_dump_ops(ops);					\
1146 		selftest_running = false;				\
1147 		-EFAULT;						\
1148 })
1149 
arm_lpae_run_tests(struct io_pgtable_cfg * cfg)1150 static int __init arm_lpae_run_tests(struct io_pgtable_cfg *cfg)
1151 {
1152 	static const enum io_pgtable_fmt fmts[] = {
1153 		ARM_64_LPAE_S1,
1154 		ARM_64_LPAE_S2,
1155 	};
1156 
1157 	int i, j;
1158 	unsigned long iova;
1159 	size_t size;
1160 	struct io_pgtable_ops *ops;
1161 
1162 	selftest_running = true;
1163 
1164 	for (i = 0; i < ARRAY_SIZE(fmts); ++i) {
1165 		cfg_cookie = cfg;
1166 		ops = alloc_io_pgtable_ops(fmts[i], cfg, cfg);
1167 		if (!ops) {
1168 			pr_err("selftest: failed to allocate io pgtable ops\n");
1169 			return -ENOMEM;
1170 		}
1171 
1172 		/*
1173 		 * Initial sanity checks.
1174 		 * Empty page tables shouldn't provide any translations.
1175 		 */
1176 		if (ops->iova_to_phys(ops, 42))
1177 			return __FAIL(ops, i);
1178 
1179 		if (ops->iova_to_phys(ops, SZ_1G + 42))
1180 			return __FAIL(ops, i);
1181 
1182 		if (ops->iova_to_phys(ops, SZ_2G + 42))
1183 			return __FAIL(ops, i);
1184 
1185 		/*
1186 		 * Distinct mappings of different granule sizes.
1187 		 */
1188 		iova = 0;
1189 		for_each_set_bit(j, &cfg->pgsize_bitmap, BITS_PER_LONG) {
1190 			size = 1UL << j;
1191 
1192 			if (ops->map(ops, iova, iova, size, IOMMU_READ |
1193 							    IOMMU_WRITE |
1194 							    IOMMU_NOEXEC |
1195 							    IOMMU_CACHE))
1196 				return __FAIL(ops, i);
1197 
1198 			/* Overlapping mappings */
1199 			if (!ops->map(ops, iova, iova + size, size,
1200 				      IOMMU_READ | IOMMU_NOEXEC))
1201 				return __FAIL(ops, i);
1202 
1203 			if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
1204 				return __FAIL(ops, i);
1205 
1206 			iova += SZ_1G;
1207 		}
1208 
1209 		/* Partial unmap */
1210 		size = 1UL << __ffs(cfg->pgsize_bitmap);
1211 		if (ops->unmap(ops, SZ_1G + size, size, NULL) != size)
1212 			return __FAIL(ops, i);
1213 
1214 		/* Remap of partial unmap */
1215 		if (ops->map(ops, SZ_1G + size, size, size, IOMMU_READ))
1216 			return __FAIL(ops, i);
1217 
1218 		if (ops->iova_to_phys(ops, SZ_1G + size + 42) != (size + 42))
1219 			return __FAIL(ops, i);
1220 
1221 		/* Full unmap */
1222 		iova = 0;
1223 		for_each_set_bit(j, &cfg->pgsize_bitmap, BITS_PER_LONG) {
1224 			size = 1UL << j;
1225 
1226 			if (ops->unmap(ops, iova, size, NULL) != size)
1227 				return __FAIL(ops, i);
1228 
1229 			if (ops->iova_to_phys(ops, iova + 42))
1230 				return __FAIL(ops, i);
1231 
1232 			/* Remap full block */
1233 			if (ops->map(ops, iova, iova, size, IOMMU_WRITE))
1234 				return __FAIL(ops, i);
1235 
1236 			if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
1237 				return __FAIL(ops, i);
1238 
1239 			iova += SZ_1G;
1240 		}
1241 
1242 		free_io_pgtable_ops(ops);
1243 	}
1244 
1245 	selftest_running = false;
1246 	return 0;
1247 }
1248 
arm_lpae_do_selftests(void)1249 static int __init arm_lpae_do_selftests(void)
1250 {
1251 	static const unsigned long pgsize[] = {
1252 		SZ_4K | SZ_2M | SZ_1G,
1253 		SZ_16K | SZ_32M,
1254 		SZ_64K | SZ_512M,
1255 	};
1256 
1257 	static const unsigned int ias[] = {
1258 		32, 36, 40, 42, 44, 48,
1259 	};
1260 
1261 	int i, j, pass = 0, fail = 0;
1262 	struct io_pgtable_cfg cfg = {
1263 		.tlb = &dummy_tlb_ops,
1264 		.oas = 48,
1265 		.coherent_walk = true,
1266 	};
1267 
1268 	for (i = 0; i < ARRAY_SIZE(pgsize); ++i) {
1269 		for (j = 0; j < ARRAY_SIZE(ias); ++j) {
1270 			cfg.pgsize_bitmap = pgsize[i];
1271 			cfg.ias = ias[j];
1272 			pr_info("selftest: pgsize_bitmap 0x%08lx, IAS %u\n",
1273 				pgsize[i], ias[j]);
1274 			if (arm_lpae_run_tests(&cfg))
1275 				fail++;
1276 			else
1277 				pass++;
1278 		}
1279 	}
1280 
1281 	pr_info("selftest: completed with %d PASS %d FAIL\n", pass, fail);
1282 	return fail ? -EFAULT : 0;
1283 }
1284 subsys_initcall(arm_lpae_do_selftests);
1285 #endif
1286