2 * CPU-agnostic ARM page table allocator.
4 * ARMv7 Short-descriptor format, supporting
5 * - Basic memory attributes
6 * - Simplified access permissions (AP[2:1] model)
7 * - Backwards-compatible TEX remap
8 * - Large pages/supersections (if indicated by the caller)
11 * - Legacy access permissions (AP[2:0] model)
13 * Almost certainly never supporting:
17 * This program is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License version 2 as
19 * published by the Free Software Foundation.
21 * This program is distributed in the hope that it will be useful,
22 * but WITHOUT ANY WARRANTY; without even the implied warranty of
23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
24 * GNU General Public License for more details.
26 * You should have received a copy of the GNU General Public License
27 * along with this program. If not, see <http://www.gnu.org/licenses/>.
29 * Copyright (C) 2014-2015 ARM Limited
30 * Copyright (c) 2014-2015 MediaTek Inc.
33 #define pr_fmt(fmt) "arm-v7s io-pgtable: " fmt
35 #include <linux/atomic.h>
36 #include <linux/dma-mapping.h>
37 #include <linux/gfp.h>
38 #include <linux/iommu.h>
39 #include <linux/kernel.h>
40 #include <linux/kmemleak.h>
41 #include <linux/sizes.h>
42 #include <linux/slab.h>
43 #include <linux/spinlock.h>
44 #include <linux/types.h>
46 #include <asm/barrier.h>
48 #include "io-pgtable.h"
50 /* Struct accessors */
51 #define io_pgtable_to_data(x) \
52 container_of((x), struct arm_v7s_io_pgtable, iop)
54 #define io_pgtable_ops_to_data(x) \
55 io_pgtable_to_data(io_pgtable_ops_to_pgtable(x))
58 * We have 32 bits total; 12 bits resolved at level 1, 8 bits at level 2,
59 * and 12 bits in a page. With some carefully-chosen coefficients we can
60 * hide the ugly inconsistencies behind these macros and at least let the
61 * rest of the code pretend to be somewhat sane.
63 #define ARM_V7S_ADDR_BITS 32
64 #define _ARM_V7S_LVL_BITS(lvl) (16 - (lvl) * 4)
65 #define ARM_V7S_LVL_SHIFT(lvl) (ARM_V7S_ADDR_BITS - (4 + 8 * (lvl)))
66 #define ARM_V7S_TABLE_SHIFT 10
68 #define ARM_V7S_PTES_PER_LVL(lvl) (1 << _ARM_V7S_LVL_BITS(lvl))
69 #define ARM_V7S_TABLE_SIZE(lvl) \
70 (ARM_V7S_PTES_PER_LVL(lvl) * sizeof(arm_v7s_iopte))
72 #define ARM_V7S_BLOCK_SIZE(lvl) (1UL << ARM_V7S_LVL_SHIFT(lvl))
73 #define ARM_V7S_LVL_MASK(lvl) ((u32)(~0U << ARM_V7S_LVL_SHIFT(lvl)))
74 #define ARM_V7S_TABLE_MASK ((u32)(~0U << ARM_V7S_TABLE_SHIFT))
75 #define _ARM_V7S_IDX_MASK(lvl) (ARM_V7S_PTES_PER_LVL(lvl) - 1)
76 #define ARM_V7S_LVL_IDX(addr, lvl) ({ \
78 ((u32)(addr) >> ARM_V7S_LVL_SHIFT(_l)) & _ARM_V7S_IDX_MASK(_l); \
82 * Large page/supersection entries are effectively a block of 16 page/section
83 * entries, along the lines of the LPAE contiguous hint, but all with the
84 * same output address. For want of a better common name we'll call them
85 * "contiguous" versions of their respective page/section entries here, but
86 * noting the distinction (WRT to TLB maintenance) that they represent *one*
87 * entry repeated 16 times, not 16 separate entries (as in the LPAE case).
89 #define ARM_V7S_CONT_PAGES 16
91 /* PTE type bits: these are all mixed up with XN/PXN bits in most cases */
92 #define ARM_V7S_PTE_TYPE_TABLE 0x1
93 #define ARM_V7S_PTE_TYPE_PAGE 0x2
94 #define ARM_V7S_PTE_TYPE_CONT_PAGE 0x1
96 #define ARM_V7S_PTE_IS_VALID(pte) (((pte) & 0x3) != 0)
97 #define ARM_V7S_PTE_IS_TABLE(pte, lvl) \
98 ((lvl) == 1 && (((pte) & 0x3) == ARM_V7S_PTE_TYPE_TABLE))
100 /* Page table bits */
101 #define ARM_V7S_ATTR_XN(lvl) BIT(4 * (2 - (lvl)))
102 #define ARM_V7S_ATTR_B BIT(2)
103 #define ARM_V7S_ATTR_C BIT(3)
104 #define ARM_V7S_ATTR_NS_TABLE BIT(3)
105 #define ARM_V7S_ATTR_NS_SECTION BIT(19)
107 #define ARM_V7S_CONT_SECTION BIT(18)
108 #define ARM_V7S_CONT_PAGE_XN_SHIFT 15
111 * The attribute bits are consistently ordered*, but occupy bits [17:10] of
112 * a level 1 PTE vs. bits [11:4] at level 2. Thus we define the individual
113 * fields relative to that 8-bit block, plus a total shift relative to the PTE.
115 #define ARM_V7S_ATTR_SHIFT(lvl) (16 - (lvl) * 6)
117 #define ARM_V7S_ATTR_MASK 0xff
118 #define ARM_V7S_ATTR_AP0 BIT(0)
119 #define ARM_V7S_ATTR_AP1 BIT(1)
120 #define ARM_V7S_ATTR_AP2 BIT(5)
121 #define ARM_V7S_ATTR_S BIT(6)
122 #define ARM_V7S_ATTR_NG BIT(7)
123 #define ARM_V7S_TEX_SHIFT 2
124 #define ARM_V7S_TEX_MASK 0x7
125 #define ARM_V7S_ATTR_TEX(val) (((val) & ARM_V7S_TEX_MASK) << ARM_V7S_TEX_SHIFT)
127 #define ARM_V7S_ATTR_MTK_4GB BIT(9) /* MTK extend it for 4GB mode */
129 /* *well, except for TEX on level 2 large pages, of course :( */
130 #define ARM_V7S_CONT_PAGE_TEX_SHIFT 6
131 #define ARM_V7S_CONT_PAGE_TEX_MASK (ARM_V7S_TEX_MASK << ARM_V7S_CONT_PAGE_TEX_SHIFT)
133 /* Simplified access permissions */
134 #define ARM_V7S_PTE_AF ARM_V7S_ATTR_AP0
135 #define ARM_V7S_PTE_AP_UNPRIV ARM_V7S_ATTR_AP1
136 #define ARM_V7S_PTE_AP_RDONLY ARM_V7S_ATTR_AP2
139 #define ARM_V7S_RGN_NC 0
140 #define ARM_V7S_RGN_WBWA 1
141 #define ARM_V7S_RGN_WT 2
142 #define ARM_V7S_RGN_WB 3
144 #define ARM_V7S_PRRR_TYPE_DEVICE 1
145 #define ARM_V7S_PRRR_TYPE_NORMAL 2
146 #define ARM_V7S_PRRR_TR(n, type) (((type) & 0x3) << ((n) * 2))
147 #define ARM_V7S_PRRR_DS0 BIT(16)
148 #define ARM_V7S_PRRR_DS1 BIT(17)
149 #define ARM_V7S_PRRR_NS0 BIT(18)
150 #define ARM_V7S_PRRR_NS1 BIT(19)
151 #define ARM_V7S_PRRR_NOS(n) BIT((n) + 24)
153 #define ARM_V7S_NMRR_IR(n, attr) (((attr) & 0x3) << ((n) * 2))
154 #define ARM_V7S_NMRR_OR(n, attr) (((attr) & 0x3) << ((n) * 2 + 16))
156 #define ARM_V7S_TTBR_S BIT(1)
157 #define ARM_V7S_TTBR_NOS BIT(5)
158 #define ARM_V7S_TTBR_ORGN_ATTR(attr) (((attr) & 0x3) << 3)
159 #define ARM_V7S_TTBR_IRGN_ATTR(attr) \
160 ((((attr) & 0x1) << 6) | (((attr) & 0x2) >> 1))
162 #define ARM_V7S_TCR_PD1 BIT(5)
164 #ifdef CONFIG_ZONE_DMA32
165 #define ARM_V7S_TABLE_GFP_DMA GFP_DMA32
166 #define ARM_V7S_TABLE_SLAB_FLAGS SLAB_CACHE_DMA32
168 #define ARM_V7S_TABLE_GFP_DMA GFP_DMA
169 #define ARM_V7S_TABLE_SLAB_FLAGS SLAB_CACHE_DMA
172 typedef u32 arm_v7s_iopte;
174 static bool selftest_running;
176 struct arm_v7s_io_pgtable {
177 struct io_pgtable iop;
180 struct kmem_cache *l2_tables;
181 spinlock_t split_lock;
184 static dma_addr_t __arm_v7s_dma_addr(void *pages)
186 return (dma_addr_t)virt_to_phys(pages);
189 static arm_v7s_iopte *iopte_deref(arm_v7s_iopte pte, int lvl)
191 if (ARM_V7S_PTE_IS_TABLE(pte, lvl))
192 pte &= ARM_V7S_TABLE_MASK;
194 pte &= ARM_V7S_LVL_MASK(lvl);
195 return phys_to_virt(pte);
198 static void *__arm_v7s_alloc_table(int lvl, gfp_t gfp,
199 struct arm_v7s_io_pgtable *data)
201 struct io_pgtable_cfg *cfg = &data->iop.cfg;
202 struct device *dev = cfg->iommu_dev;
205 size_t size = ARM_V7S_TABLE_SIZE(lvl);
209 table = (void *)__get_free_pages(
210 __GFP_ZERO | ARM_V7S_TABLE_GFP_DMA, get_order(size));
212 table = kmem_cache_zalloc(data->l2_tables, gfp);
213 phys = virt_to_phys(table);
214 if (phys != (arm_v7s_iopte)phys) {
215 /* Doesn't fit in PTE */
216 dev_err(dev, "Page table does not fit in PTE: %pa", &phys);
219 if (table && !(cfg->quirks & IO_PGTABLE_QUIRK_NO_DMA)) {
220 dma = dma_map_single(dev, table, size, DMA_TO_DEVICE);
221 if (dma_mapping_error(dev, dma))
224 * We depend on the IOMMU being able to work with any physical
225 * address directly, so if the DMA layer suggests otherwise by
226 * translating or truncating them, that bodes very badly...
232 kmemleak_ignore(table);
236 dev_err(dev, "Cannot accommodate DMA translation for IOMMU page tables\n");
237 dma_unmap_single(dev, dma, size, DMA_TO_DEVICE);
240 free_pages((unsigned long)table, get_order(size));
242 kmem_cache_free(data->l2_tables, table);
246 static void __arm_v7s_free_table(void *table, int lvl,
247 struct arm_v7s_io_pgtable *data)
249 struct io_pgtable_cfg *cfg = &data->iop.cfg;
250 struct device *dev = cfg->iommu_dev;
251 size_t size = ARM_V7S_TABLE_SIZE(lvl);
253 if (!(cfg->quirks & IO_PGTABLE_QUIRK_NO_DMA))
254 dma_unmap_single(dev, __arm_v7s_dma_addr(table), size,
257 free_pages((unsigned long)table, get_order(size));
259 kmem_cache_free(data->l2_tables, table);
262 static void __arm_v7s_pte_sync(arm_v7s_iopte *ptep, int num_entries,
263 struct io_pgtable_cfg *cfg)
265 if (cfg->quirks & IO_PGTABLE_QUIRK_NO_DMA)
268 dma_sync_single_for_device(cfg->iommu_dev, __arm_v7s_dma_addr(ptep),
269 num_entries * sizeof(*ptep), DMA_TO_DEVICE);
271 static void __arm_v7s_set_pte(arm_v7s_iopte *ptep, arm_v7s_iopte pte,
272 int num_entries, struct io_pgtable_cfg *cfg)
276 for (i = 0; i < num_entries; i++)
279 __arm_v7s_pte_sync(ptep, num_entries, cfg);
282 static arm_v7s_iopte arm_v7s_prot_to_pte(int prot, int lvl,
283 struct io_pgtable_cfg *cfg)
285 bool ap = !(cfg->quirks & IO_PGTABLE_QUIRK_NO_PERMS);
286 arm_v7s_iopte pte = ARM_V7S_ATTR_NG | ARM_V7S_ATTR_S;
288 if (!(prot & IOMMU_MMIO))
289 pte |= ARM_V7S_ATTR_TEX(1);
291 pte |= ARM_V7S_PTE_AF;
292 if (!(prot & IOMMU_PRIV))
293 pte |= ARM_V7S_PTE_AP_UNPRIV;
294 if (!(prot & IOMMU_WRITE))
295 pte |= ARM_V7S_PTE_AP_RDONLY;
297 pte <<= ARM_V7S_ATTR_SHIFT(lvl);
299 if ((prot & IOMMU_NOEXEC) && ap)
300 pte |= ARM_V7S_ATTR_XN(lvl);
301 if (prot & IOMMU_MMIO)
302 pte |= ARM_V7S_ATTR_B;
303 else if (prot & IOMMU_CACHE)
304 pte |= ARM_V7S_ATTR_B | ARM_V7S_ATTR_C;
306 pte |= ARM_V7S_PTE_TYPE_PAGE;
307 if (lvl == 1 && (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS))
308 pte |= ARM_V7S_ATTR_NS_SECTION;
310 if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_MTK_4GB)
311 pte |= ARM_V7S_ATTR_MTK_4GB;
316 static int arm_v7s_pte_to_prot(arm_v7s_iopte pte, int lvl)
318 int prot = IOMMU_READ;
319 arm_v7s_iopte attr = pte >> ARM_V7S_ATTR_SHIFT(lvl);
321 if (!(attr & ARM_V7S_PTE_AP_RDONLY))
323 if (!(attr & ARM_V7S_PTE_AP_UNPRIV))
325 if ((attr & (ARM_V7S_TEX_MASK << ARM_V7S_TEX_SHIFT)) == 0)
327 else if (pte & ARM_V7S_ATTR_C)
329 if (pte & ARM_V7S_ATTR_XN(lvl))
330 prot |= IOMMU_NOEXEC;
335 static arm_v7s_iopte arm_v7s_pte_to_cont(arm_v7s_iopte pte, int lvl)
338 pte |= ARM_V7S_CONT_SECTION;
339 } else if (lvl == 2) {
340 arm_v7s_iopte xn = pte & ARM_V7S_ATTR_XN(lvl);
341 arm_v7s_iopte tex = pte & ARM_V7S_CONT_PAGE_TEX_MASK;
343 pte ^= xn | tex | ARM_V7S_PTE_TYPE_PAGE;
344 pte |= (xn << ARM_V7S_CONT_PAGE_XN_SHIFT) |
345 (tex << ARM_V7S_CONT_PAGE_TEX_SHIFT) |
346 ARM_V7S_PTE_TYPE_CONT_PAGE;
351 static arm_v7s_iopte arm_v7s_cont_to_pte(arm_v7s_iopte pte, int lvl)
354 pte &= ~ARM_V7S_CONT_SECTION;
355 } else if (lvl == 2) {
356 arm_v7s_iopte xn = pte & BIT(ARM_V7S_CONT_PAGE_XN_SHIFT);
357 arm_v7s_iopte tex = pte & (ARM_V7S_CONT_PAGE_TEX_MASK <<
358 ARM_V7S_CONT_PAGE_TEX_SHIFT);
360 pte ^= xn | tex | ARM_V7S_PTE_TYPE_CONT_PAGE;
361 pte |= (xn >> ARM_V7S_CONT_PAGE_XN_SHIFT) |
362 (tex >> ARM_V7S_CONT_PAGE_TEX_SHIFT) |
363 ARM_V7S_PTE_TYPE_PAGE;
368 static bool arm_v7s_pte_is_cont(arm_v7s_iopte pte, int lvl)
370 if (lvl == 1 && !ARM_V7S_PTE_IS_TABLE(pte, lvl))
371 return pte & ARM_V7S_CONT_SECTION;
373 return !(pte & ARM_V7S_PTE_TYPE_PAGE);
377 static size_t __arm_v7s_unmap(struct arm_v7s_io_pgtable *, unsigned long,
378 size_t, int, arm_v7s_iopte *);
380 static int arm_v7s_init_pte(struct arm_v7s_io_pgtable *data,
381 unsigned long iova, phys_addr_t paddr, int prot,
382 int lvl, int num_entries, arm_v7s_iopte *ptep)
384 struct io_pgtable_cfg *cfg = &data->iop.cfg;
388 for (i = 0; i < num_entries; i++)
389 if (ARM_V7S_PTE_IS_TABLE(ptep[i], lvl)) {
391 * We need to unmap and free the old table before
392 * overwriting it with a block entry.
395 size_t sz = ARM_V7S_BLOCK_SIZE(lvl);
397 tblp = ptep - ARM_V7S_LVL_IDX(iova, lvl);
398 if (WARN_ON(__arm_v7s_unmap(data, iova + i * sz,
399 sz, lvl, tblp) != sz))
401 } else if (ptep[i]) {
402 /* We require an unmap first */
403 WARN_ON(!selftest_running);
407 pte = arm_v7s_prot_to_pte(prot, lvl, cfg);
409 pte = arm_v7s_pte_to_cont(pte, lvl);
411 pte |= paddr & ARM_V7S_LVL_MASK(lvl);
413 __arm_v7s_set_pte(ptep, pte, num_entries, cfg);
417 static arm_v7s_iopte arm_v7s_install_table(arm_v7s_iopte *table,
420 struct io_pgtable_cfg *cfg)
422 arm_v7s_iopte old, new;
424 new = virt_to_phys(table) | ARM_V7S_PTE_TYPE_TABLE;
425 if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS)
426 new |= ARM_V7S_ATTR_NS_TABLE;
429 * Ensure the table itself is visible before its PTE can be.
430 * Whilst we could get away with cmpxchg64_release below, this
431 * doesn't have any ordering semantics when !CONFIG_SMP.
435 old = cmpxchg_relaxed(ptep, curr, new);
436 __arm_v7s_pte_sync(ptep, 1, cfg);
441 static int __arm_v7s_map(struct arm_v7s_io_pgtable *data, unsigned long iova,
442 phys_addr_t paddr, size_t size, int prot,
443 int lvl, arm_v7s_iopte *ptep)
445 struct io_pgtable_cfg *cfg = &data->iop.cfg;
446 arm_v7s_iopte pte, *cptep;
447 int num_entries = size >> ARM_V7S_LVL_SHIFT(lvl);
449 /* Find our entry at the current level */
450 ptep += ARM_V7S_LVL_IDX(iova, lvl);
452 /* If we can install a leaf entry at this level, then do so */
454 return arm_v7s_init_pte(data, iova, paddr, prot,
455 lvl, num_entries, ptep);
457 /* We can't allocate tables at the final level */
458 if (WARN_ON(lvl == 2))
461 /* Grab a pointer to the next level */
462 pte = READ_ONCE(*ptep);
464 cptep = __arm_v7s_alloc_table(lvl + 1, GFP_ATOMIC, data);
468 pte = arm_v7s_install_table(cptep, ptep, 0, cfg);
470 __arm_v7s_free_table(cptep, lvl + 1, data);
472 /* We've no easy way of knowing if it's synced yet, so... */
473 __arm_v7s_pte_sync(ptep, 1, cfg);
476 if (ARM_V7S_PTE_IS_TABLE(pte, lvl)) {
477 cptep = iopte_deref(pte, lvl);
479 /* We require an unmap first */
480 WARN_ON(!selftest_running);
485 return __arm_v7s_map(data, iova, paddr, size, prot, lvl + 1, cptep);
488 static int arm_v7s_map(struct io_pgtable_ops *ops, unsigned long iova,
489 phys_addr_t paddr, size_t size, int prot)
491 struct arm_v7s_io_pgtable *data = io_pgtable_ops_to_data(ops);
492 struct io_pgtable *iop = &data->iop;
495 /* If no access, then nothing to do */
496 if (!(prot & (IOMMU_READ | IOMMU_WRITE)))
499 if (WARN_ON(upper_32_bits(iova) || upper_32_bits(paddr)))
502 ret = __arm_v7s_map(data, iova, paddr, size, prot, 1, data->pgd);
504 * Synchronise all PTE updates for the new mapping before there's
505 * a chance for anything to kick off a table walk for the new iova.
507 if (iop->cfg.quirks & IO_PGTABLE_QUIRK_TLBI_ON_MAP) {
508 io_pgtable_tlb_add_flush(iop, iova, size,
509 ARM_V7S_BLOCK_SIZE(2), false);
510 io_pgtable_tlb_sync(iop);
518 static void arm_v7s_free_pgtable(struct io_pgtable *iop)
520 struct arm_v7s_io_pgtable *data = io_pgtable_to_data(iop);
523 for (i = 0; i < ARM_V7S_PTES_PER_LVL(1); i++) {
524 arm_v7s_iopte pte = data->pgd[i];
526 if (ARM_V7S_PTE_IS_TABLE(pte, 1))
527 __arm_v7s_free_table(iopte_deref(pte, 1), 2, data);
529 __arm_v7s_free_table(data->pgd, 1, data);
530 kmem_cache_destroy(data->l2_tables);
534 static arm_v7s_iopte arm_v7s_split_cont(struct arm_v7s_io_pgtable *data,
535 unsigned long iova, int idx, int lvl,
538 struct io_pgtable *iop = &data->iop;
540 size_t size = ARM_V7S_BLOCK_SIZE(lvl);
543 /* Check that we didn't lose a race to get the lock */
545 if (!arm_v7s_pte_is_cont(pte, lvl))
548 ptep -= idx & (ARM_V7S_CONT_PAGES - 1);
549 pte = arm_v7s_cont_to_pte(pte, lvl);
550 for (i = 0; i < ARM_V7S_CONT_PAGES; i++)
551 ptep[i] = pte + i * size;
553 __arm_v7s_pte_sync(ptep, ARM_V7S_CONT_PAGES, &iop->cfg);
555 size *= ARM_V7S_CONT_PAGES;
556 io_pgtable_tlb_add_flush(iop, iova, size, size, true);
557 io_pgtable_tlb_sync(iop);
561 static size_t arm_v7s_split_blk_unmap(struct arm_v7s_io_pgtable *data,
562 unsigned long iova, size_t size,
563 arm_v7s_iopte blk_pte,
566 struct io_pgtable_cfg *cfg = &data->iop.cfg;
567 arm_v7s_iopte pte, *tablep;
568 int i, unmap_idx, num_entries, num_ptes;
570 tablep = __arm_v7s_alloc_table(2, GFP_ATOMIC, data);
572 return 0; /* Bytes unmapped */
574 num_ptes = ARM_V7S_PTES_PER_LVL(2);
575 num_entries = size >> ARM_V7S_LVL_SHIFT(2);
576 unmap_idx = ARM_V7S_LVL_IDX(iova, 2);
578 pte = arm_v7s_prot_to_pte(arm_v7s_pte_to_prot(blk_pte, 1), 2, cfg);
580 pte = arm_v7s_pte_to_cont(pte, 2);
582 for (i = 0; i < num_ptes; i += num_entries, pte += size) {
587 __arm_v7s_set_pte(&tablep[i], pte, num_entries, cfg);
590 pte = arm_v7s_install_table(tablep, ptep, blk_pte, cfg);
591 if (pte != blk_pte) {
592 __arm_v7s_free_table(tablep, 2, data);
594 if (!ARM_V7S_PTE_IS_TABLE(pte, 1))
597 tablep = iopte_deref(pte, 1);
598 return __arm_v7s_unmap(data, iova, size, 2, tablep);
601 io_pgtable_tlb_add_flush(&data->iop, iova, size, size, true);
605 static size_t __arm_v7s_unmap(struct arm_v7s_io_pgtable *data,
606 unsigned long iova, size_t size, int lvl,
609 arm_v7s_iopte pte[ARM_V7S_CONT_PAGES];
610 struct io_pgtable *iop = &data->iop;
611 int idx, i = 0, num_entries = size >> ARM_V7S_LVL_SHIFT(lvl);
613 /* Something went horribly wrong and we ran out of page table */
614 if (WARN_ON(lvl > 2))
617 idx = ARM_V7S_LVL_IDX(iova, lvl);
620 pte[i] = READ_ONCE(ptep[i]);
621 if (WARN_ON(!ARM_V7S_PTE_IS_VALID(pte[i])))
623 } while (++i < num_entries);
626 * If we've hit a contiguous 'large page' entry at this level, it
627 * needs splitting first, unless we're unmapping the whole lot.
629 * For splitting, we can't rewrite 16 PTEs atomically, and since we
630 * can't necessarily assume TEX remap we don't have a software bit to
631 * mark live entries being split. In practice (i.e. DMA API code), we
632 * will never be splitting large pages anyway, so just wrap this edge
633 * case in a lock for the sake of correctness and be done with it.
635 if (num_entries <= 1 && arm_v7s_pte_is_cont(pte[0], lvl)) {
638 spin_lock_irqsave(&data->split_lock, flags);
639 pte[0] = arm_v7s_split_cont(data, iova, idx, lvl, ptep);
640 spin_unlock_irqrestore(&data->split_lock, flags);
643 /* If the size matches this level, we're in the right place */
645 size_t blk_size = ARM_V7S_BLOCK_SIZE(lvl);
647 __arm_v7s_set_pte(ptep, 0, num_entries, &iop->cfg);
649 for (i = 0; i < num_entries; i++) {
650 if (ARM_V7S_PTE_IS_TABLE(pte[i], lvl)) {
651 /* Also flush any partial walks */
652 io_pgtable_tlb_add_flush(iop, iova, blk_size,
653 ARM_V7S_BLOCK_SIZE(lvl + 1), false);
654 io_pgtable_tlb_sync(iop);
655 ptep = iopte_deref(pte[i], lvl);
656 __arm_v7s_free_table(ptep, lvl + 1, data);
658 io_pgtable_tlb_add_flush(iop, iova, blk_size,
664 } else if (lvl == 1 && !ARM_V7S_PTE_IS_TABLE(pte[0], lvl)) {
666 * Insert a table at the next level to map the old region,
667 * minus the part we want to unmap
669 return arm_v7s_split_blk_unmap(data, iova, size, pte[0], ptep);
672 /* Keep on walkin' */
673 ptep = iopte_deref(pte[0], lvl);
674 return __arm_v7s_unmap(data, iova, size, lvl + 1, ptep);
677 static size_t arm_v7s_unmap(struct io_pgtable_ops *ops, unsigned long iova,
680 struct arm_v7s_io_pgtable *data = io_pgtable_ops_to_data(ops);
682 if (WARN_ON(upper_32_bits(iova)))
685 return __arm_v7s_unmap(data, iova, size, 1, data->pgd);
688 static phys_addr_t arm_v7s_iova_to_phys(struct io_pgtable_ops *ops,
691 struct arm_v7s_io_pgtable *data = io_pgtable_ops_to_data(ops);
692 arm_v7s_iopte *ptep = data->pgd, pte;
697 ptep += ARM_V7S_LVL_IDX(iova, ++lvl);
698 pte = READ_ONCE(*ptep);
699 ptep = iopte_deref(pte, lvl);
700 } while (ARM_V7S_PTE_IS_TABLE(pte, lvl));
702 if (!ARM_V7S_PTE_IS_VALID(pte))
705 mask = ARM_V7S_LVL_MASK(lvl);
706 if (arm_v7s_pte_is_cont(pte, lvl))
707 mask *= ARM_V7S_CONT_PAGES;
708 return (pte & mask) | (iova & ~mask);
711 static struct io_pgtable *arm_v7s_alloc_pgtable(struct io_pgtable_cfg *cfg,
714 struct arm_v7s_io_pgtable *data;
717 if (upper_32_bits(PHYS_OFFSET))
720 if (cfg->ias > ARM_V7S_ADDR_BITS || cfg->oas > ARM_V7S_ADDR_BITS)
723 if (cfg->quirks & ~(IO_PGTABLE_QUIRK_ARM_NS |
724 IO_PGTABLE_QUIRK_NO_PERMS |
725 IO_PGTABLE_QUIRK_TLBI_ON_MAP |
726 IO_PGTABLE_QUIRK_ARM_MTK_4GB |
727 IO_PGTABLE_QUIRK_NO_DMA))
730 /* If ARM_MTK_4GB is enabled, the NO_PERMS is also expected. */
731 if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_MTK_4GB &&
732 !(cfg->quirks & IO_PGTABLE_QUIRK_NO_PERMS))
735 data = kmalloc(sizeof(*data), GFP_KERNEL);
739 spin_lock_init(&data->split_lock);
740 data->l2_tables = kmem_cache_create("io-pgtable_armv7s_l2",
741 ARM_V7S_TABLE_SIZE(2),
742 ARM_V7S_TABLE_SIZE(2),
743 ARM_V7S_TABLE_SLAB_FLAGS, NULL);
744 if (!data->l2_tables)
747 data->iop.ops = (struct io_pgtable_ops) {
749 .unmap = arm_v7s_unmap,
750 .iova_to_phys = arm_v7s_iova_to_phys,
753 /* We have to do this early for __arm_v7s_alloc_table to work... */
754 data->iop.cfg = *cfg;
757 * Unless the IOMMU driver indicates supersection support by
758 * having SZ_16M set in the initial bitmap, they won't be used.
760 cfg->pgsize_bitmap &= SZ_4K | SZ_64K | SZ_1M | SZ_16M;
762 /* TCR: T0SZ=0, disable TTBR1 */
763 cfg->arm_v7s_cfg.tcr = ARM_V7S_TCR_PD1;
766 * TEX remap: the indices used map to the closest equivalent types
767 * under the non-TEX-remap interpretation of those attribute bits,
768 * excepting various implementation-defined aspects of shareability.
770 cfg->arm_v7s_cfg.prrr = ARM_V7S_PRRR_TR(1, ARM_V7S_PRRR_TYPE_DEVICE) |
771 ARM_V7S_PRRR_TR(4, ARM_V7S_PRRR_TYPE_NORMAL) |
772 ARM_V7S_PRRR_TR(7, ARM_V7S_PRRR_TYPE_NORMAL) |
773 ARM_V7S_PRRR_DS0 | ARM_V7S_PRRR_DS1 |
774 ARM_V7S_PRRR_NS1 | ARM_V7S_PRRR_NOS(7);
775 cfg->arm_v7s_cfg.nmrr = ARM_V7S_NMRR_IR(7, ARM_V7S_RGN_WBWA) |
776 ARM_V7S_NMRR_OR(7, ARM_V7S_RGN_WBWA);
778 /* Looking good; allocate a pgd */
779 data->pgd = __arm_v7s_alloc_table(1, GFP_KERNEL, data);
783 /* Ensure the empty pgd is visible before any actual TTBR write */
787 cfg->arm_v7s_cfg.ttbr[0] = virt_to_phys(data->pgd) |
788 ARM_V7S_TTBR_S | ARM_V7S_TTBR_NOS |
789 ARM_V7S_TTBR_IRGN_ATTR(ARM_V7S_RGN_WBWA) |
790 ARM_V7S_TTBR_ORGN_ATTR(ARM_V7S_RGN_WBWA);
791 cfg->arm_v7s_cfg.ttbr[1] = 0;
795 kmem_cache_destroy(data->l2_tables);
800 struct io_pgtable_init_fns io_pgtable_arm_v7s_init_fns = {
801 .alloc = arm_v7s_alloc_pgtable,
802 .free = arm_v7s_free_pgtable,
805 #ifdef CONFIG_IOMMU_IO_PGTABLE_ARMV7S_SELFTEST
807 static struct io_pgtable_cfg *cfg_cookie;
809 static void dummy_tlb_flush_all(void *cookie)
811 WARN_ON(cookie != cfg_cookie);
814 static void dummy_tlb_add_flush(unsigned long iova, size_t size,
815 size_t granule, bool leaf, void *cookie)
817 WARN_ON(cookie != cfg_cookie);
818 WARN_ON(!(size & cfg_cookie->pgsize_bitmap));
821 static void dummy_tlb_sync(void *cookie)
823 WARN_ON(cookie != cfg_cookie);
826 static const struct iommu_gather_ops dummy_tlb_ops = {
827 .tlb_flush_all = dummy_tlb_flush_all,
828 .tlb_add_flush = dummy_tlb_add_flush,
829 .tlb_sync = dummy_tlb_sync,
832 #define __FAIL(ops) ({ \
833 WARN(1, "selftest: test failed\n"); \
834 selftest_running = false; \
838 static int __init arm_v7s_do_selftests(void)
840 struct io_pgtable_ops *ops;
841 struct io_pgtable_cfg cfg = {
842 .tlb = &dummy_tlb_ops,
845 .quirks = IO_PGTABLE_QUIRK_ARM_NS | IO_PGTABLE_QUIRK_NO_DMA,
846 .pgsize_bitmap = SZ_4K | SZ_64K | SZ_1M | SZ_16M,
848 unsigned int iova, size, iova_start;
849 unsigned int i, loopnr = 0;
851 selftest_running = true;
855 ops = alloc_io_pgtable_ops(ARM_V7S, &cfg, &cfg);
857 pr_err("selftest: failed to allocate io pgtable ops\n");
862 * Initial sanity checks.
863 * Empty page tables shouldn't provide any translations.
865 if (ops->iova_to_phys(ops, 42))
868 if (ops->iova_to_phys(ops, SZ_1G + 42))
871 if (ops->iova_to_phys(ops, SZ_2G + 42))
875 * Distinct mappings of different granule sizes.
878 for_each_set_bit(i, &cfg.pgsize_bitmap, BITS_PER_LONG) {
880 if (ops->map(ops, iova, iova, size, IOMMU_READ |
886 /* Overlapping mappings */
887 if (!ops->map(ops, iova, iova + size, size,
888 IOMMU_READ | IOMMU_NOEXEC))
891 if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
900 size = 1UL << __ffs(cfg.pgsize_bitmap);
902 iova_start = i * SZ_16M;
903 if (ops->unmap(ops, iova_start + size, size) != size)
906 /* Remap of partial unmap */
907 if (ops->map(ops, iova_start + size, size, size, IOMMU_READ))
910 if (ops->iova_to_phys(ops, iova_start + size + 42)
918 for_each_set_bit(i, &cfg.pgsize_bitmap, BITS_PER_LONG) {
921 if (ops->unmap(ops, iova, size) != size)
924 if (ops->iova_to_phys(ops, iova + 42))
927 /* Remap full block */
928 if (ops->map(ops, iova, iova, size, IOMMU_WRITE))
931 if (ops->iova_to_phys(ops, iova + 42) != (iova + 42))
937 free_io_pgtable_ops(ops);
939 selftest_running = false;
941 pr_info("self test ok\n");
944 subsys_initcall(arm_v7s_do_selftests);