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