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1/*
2 * linux/arch/arm/mm/mmu.c
3 *
4 * Copyright (C) 1995-2005 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10#include <linux/module.h>
11#include <linux/kernel.h>
12#include <linux/errno.h>
13#include <linux/init.h>
14#include <linux/mman.h>
15#include <linux/nodemask.h>
16#include <linux/memblock.h>
17#include <linux/fs.h>
18#include <linux/vmalloc.h>
19#include <linux/sizes.h>
20
21#include <asm/cp15.h>
22#include <asm/cputype.h>
23#include <asm/sections.h>
24#include <asm/cachetype.h>
25#include <asm/fixmap.h>
26#include <asm/sections.h>
27#include <asm/setup.h>
28#include <asm/smp_plat.h>
29#include <asm/tlb.h>
30#include <asm/highmem.h>
31#include <asm/system_info.h>
32#include <asm/traps.h>
33#include <asm/procinfo.h>
34#include <asm/memory.h>
35
36#include <asm/mach/arch.h>
37#include <asm/mach/map.h>
38#include <asm/mach/pci.h>
39#include <asm/fixmap.h>
40
41#include "fault.h"
42#include "mm.h"
43#include "tcm.h"
44
45/*
46 * empty_zero_page is a special page that is used for
47 * zero-initialized data and COW.
48 */
49struct page *empty_zero_page;
50EXPORT_SYMBOL(empty_zero_page);
51
52/*
53 * The pmd table for the upper-most set of pages.
54 */
55pmd_t *top_pmd;
56
57pmdval_t user_pmd_table = _PAGE_USER_TABLE;
58
59#define CPOLICY_UNCACHED 0
60#define CPOLICY_BUFFERED 1
61#define CPOLICY_WRITETHROUGH 2
62#define CPOLICY_WRITEBACK 3
63#define CPOLICY_WRITEALLOC 4
64
65static unsigned int cachepolicy __initdata = CPOLICY_WRITEBACK;
66static unsigned int ecc_mask __initdata = 0;
67pgprot_t pgprot_user;
68pgprot_t pgprot_kernel;
69pgprot_t pgprot_hyp_device;
70pgprot_t pgprot_s2;
71pgprot_t pgprot_s2_device;
72
73EXPORT_SYMBOL(pgprot_user);
74EXPORT_SYMBOL(pgprot_kernel);
75
76struct cachepolicy {
77 const char policy[16];
78 unsigned int cr_mask;
79 pmdval_t pmd;
80 pteval_t pte;
81 pteval_t pte_s2;
82};
83
84#ifdef CONFIG_ARM_LPAE
85#define s2_policy(policy) policy
86#else
87#define s2_policy(policy) 0
88#endif
89
90unsigned long kimage_voffset __ro_after_init;
91
92static struct cachepolicy cache_policies[] __initdata = {
93 {
94 .policy = "uncached",
95 .cr_mask = CR_W|CR_C,
96 .pmd = PMD_SECT_UNCACHED,
97 .pte = L_PTE_MT_UNCACHED,
98 .pte_s2 = s2_policy(L_PTE_S2_MT_UNCACHED),
99 }, {
100 .policy = "buffered",
101 .cr_mask = CR_C,
102 .pmd = PMD_SECT_BUFFERED,
103 .pte = L_PTE_MT_BUFFERABLE,
104 .pte_s2 = s2_policy(L_PTE_S2_MT_UNCACHED),
105 }, {
106 .policy = "writethrough",
107 .cr_mask = 0,
108 .pmd = PMD_SECT_WT,
109 .pte = L_PTE_MT_WRITETHROUGH,
110 .pte_s2 = s2_policy(L_PTE_S2_MT_WRITETHROUGH),
111 }, {
112 .policy = "writeback",
113 .cr_mask = 0,
114 .pmd = PMD_SECT_WB,
115 .pte = L_PTE_MT_WRITEBACK,
116 .pte_s2 = s2_policy(L_PTE_S2_MT_WRITEBACK),
117 }, {
118 .policy = "writealloc",
119 .cr_mask = 0,
120 .pmd = PMD_SECT_WBWA,
121 .pte = L_PTE_MT_WRITEALLOC,
122 .pte_s2 = s2_policy(L_PTE_S2_MT_WRITEBACK),
123 }
124};
125
126#ifdef CONFIG_CPU_CP15
127static unsigned long initial_pmd_value __initdata = 0;
128
129/*
130 * Initialise the cache_policy variable with the initial state specified
131 * via the "pmd" value. This is used to ensure that on ARMv6 and later,
132 * the C code sets the page tables up with the same policy as the head
133 * assembly code, which avoids an illegal state where the TLBs can get
134 * confused. See comments in early_cachepolicy() for more information.
135 */
136void __init init_default_cache_policy(unsigned long pmd)
137{
138 int i;
139
140 initial_pmd_value = pmd;
141
142 pmd &= PMD_SECT_CACHE_MASK;
143
144 for (i = 0; i < ARRAY_SIZE(cache_policies); i++)
145 if (cache_policies[i].pmd == pmd) {
146 cachepolicy = i;
147 break;
148 }
149
150 if (i == ARRAY_SIZE(cache_policies))
151 pr_err("ERROR: could not find cache policy\n");
152}
153
154/*
155 * These are useful for identifying cache coherency problems by allowing
156 * the cache or the cache and writebuffer to be turned off. (Note: the
157 * write buffer should not be on and the cache off).
158 */
159static int __init early_cachepolicy(char *p)
160{
161 int i, selected = -1;
162
163 for (i = 0; i < ARRAY_SIZE(cache_policies); i++) {
164 int len = strlen(cache_policies[i].policy);
165
166 if (memcmp(p, cache_policies[i].policy, len) == 0) {
167 selected = i;
168 break;
169 }
170 }
171
172 if (selected == -1)
173 pr_err("ERROR: unknown or unsupported cache policy\n");
174
175 /*
176 * This restriction is partly to do with the way we boot; it is
177 * unpredictable to have memory mapped using two different sets of
178 * memory attributes (shared, type, and cache attribs). We can not
179 * change these attributes once the initial assembly has setup the
180 * page tables.
181 */
182 if (cpu_architecture() >= CPU_ARCH_ARMv6 && selected != cachepolicy) {
183 pr_warn("Only cachepolicy=%s supported on ARMv6 and later\n",
184 cache_policies[cachepolicy].policy);
185 return 0;
186 }
187
188 if (selected != cachepolicy) {
189 unsigned long cr = __clear_cr(cache_policies[selected].cr_mask);
190 cachepolicy = selected;
191 flush_cache_all();
192 set_cr(cr);
193 }
194 return 0;
195}
196early_param("cachepolicy", early_cachepolicy);
197
198static int __init early_nocache(char *__unused)
199{
200 char *p = "buffered";
201 pr_warn("nocache is deprecated; use cachepolicy=%s\n", p);
202 early_cachepolicy(p);
203 return 0;
204}
205early_param("nocache", early_nocache);
206
207static int __init early_nowrite(char *__unused)
208{
209 char *p = "uncached";
210 pr_warn("nowb is deprecated; use cachepolicy=%s\n", p);
211 early_cachepolicy(p);
212 return 0;
213}
214early_param("nowb", early_nowrite);
215
216#ifndef CONFIG_ARM_LPAE
217static int __init early_ecc(char *p)
218{
219 if (memcmp(p, "on", 2) == 0)
220 ecc_mask = PMD_PROTECTION;
221 else if (memcmp(p, "off", 3) == 0)
222 ecc_mask = 0;
223 return 0;
224}
225early_param("ecc", early_ecc);
226#endif
227
228#else /* ifdef CONFIG_CPU_CP15 */
229
230static int __init early_cachepolicy(char *p)
231{
232 pr_warn("cachepolicy kernel parameter not supported without cp15\n");
233}
234early_param("cachepolicy", early_cachepolicy);
235
236static int __init noalign_setup(char *__unused)
237{
238 pr_warn("noalign kernel parameter not supported without cp15\n");
239}
240__setup("noalign", noalign_setup);
241
242#endif /* ifdef CONFIG_CPU_CP15 / else */
243
244#define PROT_PTE_DEVICE L_PTE_PRESENT|L_PTE_YOUNG|L_PTE_DIRTY|L_PTE_XN
245#define PROT_PTE_S2_DEVICE PROT_PTE_DEVICE
246#define PROT_SECT_DEVICE PMD_TYPE_SECT|PMD_SECT_AP_WRITE
247
248static struct mem_type mem_types[] __ro_after_init = {
249 [MT_DEVICE] = { /* Strongly ordered / ARMv6 shared device */
250 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_SHARED |
251 L_PTE_SHARED,
252 .prot_pte_s2 = s2_policy(PROT_PTE_S2_DEVICE) |
253 s2_policy(L_PTE_S2_MT_DEV_SHARED) |
254 L_PTE_SHARED,
255 .prot_l1 = PMD_TYPE_TABLE,
256 .prot_sect = PROT_SECT_DEVICE | PMD_SECT_S,
257 .domain = DOMAIN_IO,
258 },
259 [MT_DEVICE_NONSHARED] = { /* ARMv6 non-shared device */
260 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_NONSHARED,
261 .prot_l1 = PMD_TYPE_TABLE,
262 .prot_sect = PROT_SECT_DEVICE,
263 .domain = DOMAIN_IO,
264 },
265 [MT_DEVICE_CACHED] = { /* ioremap_cached */
266 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_CACHED,
267 .prot_l1 = PMD_TYPE_TABLE,
268 .prot_sect = PROT_SECT_DEVICE | PMD_SECT_WB,
269 .domain = DOMAIN_IO,
270 },
271 [MT_DEVICE_WC] = { /* ioremap_wc */
272 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_WC,
273 .prot_l1 = PMD_TYPE_TABLE,
274 .prot_sect = PROT_SECT_DEVICE,
275 .domain = DOMAIN_IO,
276 },
277 [MT_UNCACHED] = {
278 .prot_pte = PROT_PTE_DEVICE,
279 .prot_l1 = PMD_TYPE_TABLE,
280 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
281 .domain = DOMAIN_IO,
282 },
283 [MT_CACHECLEAN] = {
284 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
285 .domain = DOMAIN_KERNEL,
286 },
287#ifndef CONFIG_ARM_LPAE
288 [MT_MINICLEAN] = {
289 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN | PMD_SECT_MINICACHE,
290 .domain = DOMAIN_KERNEL,
291 },
292#endif
293 [MT_LOW_VECTORS] = {
294 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
295 L_PTE_RDONLY,
296 .prot_l1 = PMD_TYPE_TABLE,
297 .domain = DOMAIN_VECTORS,
298 },
299 [MT_HIGH_VECTORS] = {
300 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
301 L_PTE_USER | L_PTE_RDONLY,
302 .prot_l1 = PMD_TYPE_TABLE,
303 .domain = DOMAIN_VECTORS,
304 },
305 [MT_MEMORY_RWX] = {
306 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
307 .prot_l1 = PMD_TYPE_TABLE,
308 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
309 .domain = DOMAIN_KERNEL,
310 },
311 [MT_MEMORY_RW] = {
312 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
313 L_PTE_XN,
314 .prot_l1 = PMD_TYPE_TABLE,
315 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
316 .domain = DOMAIN_KERNEL,
317 },
318 [MT_ROM] = {
319 .prot_sect = PMD_TYPE_SECT,
320 .domain = DOMAIN_KERNEL,
321 },
322 [MT_MEMORY_RWX_NONCACHED] = {
323 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
324 L_PTE_MT_BUFFERABLE,
325 .prot_l1 = PMD_TYPE_TABLE,
326 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
327 .domain = DOMAIN_KERNEL,
328 },
329 [MT_MEMORY_RW_DTCM] = {
330 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
331 L_PTE_XN,
332 .prot_l1 = PMD_TYPE_TABLE,
333 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
334 .domain = DOMAIN_KERNEL,
335 },
336 [MT_MEMORY_RWX_ITCM] = {
337 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
338 .prot_l1 = PMD_TYPE_TABLE,
339 .domain = DOMAIN_KERNEL,
340 },
341 [MT_MEMORY_RW_SO] = {
342 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
343 L_PTE_MT_UNCACHED | L_PTE_XN,
344 .prot_l1 = PMD_TYPE_TABLE,
345 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_SECT_S |
346 PMD_SECT_UNCACHED | PMD_SECT_XN,
347 .domain = DOMAIN_KERNEL,
348 },
349 [MT_MEMORY_DMA_READY] = {
350 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
351 L_PTE_XN,
352 .prot_l1 = PMD_TYPE_TABLE,
353 .domain = DOMAIN_KERNEL,
354 },
355};
356
357const struct mem_type *get_mem_type(unsigned int type)
358{
359 return type < ARRAY_SIZE(mem_types) ? &mem_types[type] : NULL;
360}
361EXPORT_SYMBOL(get_mem_type);
362
363static pte_t *(*pte_offset_fixmap)(pmd_t *dir, unsigned long addr);
364
365static pte_t bm_pte[PTRS_PER_PTE + PTE_HWTABLE_PTRS]
366 __aligned(PTE_HWTABLE_OFF + PTE_HWTABLE_SIZE) __initdata;
367
368static pte_t * __init pte_offset_early_fixmap(pmd_t *dir, unsigned long addr)
369{
370 return &bm_pte[pte_index(addr)];
371}
372
373static pte_t *pte_offset_late_fixmap(pmd_t *dir, unsigned long addr)
374{
375 return pte_offset_kernel(dir, addr);
376}
377
378static inline pmd_t * __init fixmap_pmd(unsigned long addr)
379{
380 pgd_t *pgd = pgd_offset_k(addr);
381 pud_t *pud = pud_offset(pgd, addr);
382 pmd_t *pmd = pmd_offset(pud, addr);
383
384 return pmd;
385}
386
387void __init early_fixmap_init(void)
388{
389 pmd_t *pmd;
390
391 /*
392 * The early fixmap range spans multiple pmds, for which
393 * we are not prepared:
394 */
395 BUILD_BUG_ON((__fix_to_virt(__end_of_early_ioremap_region) >> PMD_SHIFT)
396 != FIXADDR_TOP >> PMD_SHIFT);
397
398 pmd = fixmap_pmd(FIXADDR_TOP);
399 pmd_populate_kernel(&init_mm, pmd, bm_pte);
400
401 pte_offset_fixmap = pte_offset_early_fixmap;
402}
403
404/*
405 * To avoid TLB flush broadcasts, this uses local_flush_tlb_kernel_range().
406 * As a result, this can only be called with preemption disabled, as under
407 * stop_machine().
408 */
409void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
410{
411 unsigned long vaddr = __fix_to_virt(idx);
412 pte_t *pte = pte_offset_fixmap(pmd_off_k(vaddr), vaddr);
413
414 /* Make sure fixmap region does not exceed available allocation. */
415 BUILD_BUG_ON(FIXADDR_START + (__end_of_fixed_addresses * PAGE_SIZE) >
416 FIXADDR_END);
417 BUG_ON(idx >= __end_of_fixed_addresses);
418
419 /* we only support device mappings until pgprot_kernel has been set */
420 if (WARN_ON(pgprot_val(prot) != pgprot_val(FIXMAP_PAGE_IO) &&
421 pgprot_val(pgprot_kernel) == 0))
422 return;
423
424 if (pgprot_val(prot))
425 set_pte_at(NULL, vaddr, pte,
426 pfn_pte(phys >> PAGE_SHIFT, prot));
427 else
428 pte_clear(NULL, vaddr, pte);
429 local_flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE);
430}
431
432/*
433 * Adjust the PMD section entries according to the CPU in use.
434 */
435static void __init build_mem_type_table(void)
436{
437 struct cachepolicy *cp;
438 unsigned int cr = get_cr();
439 pteval_t user_pgprot, kern_pgprot, vecs_pgprot;
440 pteval_t hyp_device_pgprot, s2_pgprot, s2_device_pgprot;
441 int cpu_arch = cpu_architecture();
442 int i;
443
444 if (cpu_arch < CPU_ARCH_ARMv6) {
445#if defined(CONFIG_CPU_DCACHE_DISABLE)
446 if (cachepolicy > CPOLICY_BUFFERED)
447 cachepolicy = CPOLICY_BUFFERED;
448#elif defined(CONFIG_CPU_DCACHE_WRITETHROUGH)
449 if (cachepolicy > CPOLICY_WRITETHROUGH)
450 cachepolicy = CPOLICY_WRITETHROUGH;
451#endif
452 }
453 if (cpu_arch < CPU_ARCH_ARMv5) {
454 if (cachepolicy >= CPOLICY_WRITEALLOC)
455 cachepolicy = CPOLICY_WRITEBACK;
456 ecc_mask = 0;
457 }
458
459 if (is_smp()) {
460 if (cachepolicy != CPOLICY_WRITEALLOC) {
461 pr_warn("Forcing write-allocate cache policy for SMP\n");
462 cachepolicy = CPOLICY_WRITEALLOC;
463 }
464 if (!(initial_pmd_value & PMD_SECT_S)) {
465 pr_warn("Forcing shared mappings for SMP\n");
466 initial_pmd_value |= PMD_SECT_S;
467 }
468 }
469
470 /*
471 * Strip out features not present on earlier architectures.
472 * Pre-ARMv5 CPUs don't have TEX bits. Pre-ARMv6 CPUs or those
473 * without extended page tables don't have the 'Shared' bit.
474 */
475 if (cpu_arch < CPU_ARCH_ARMv5)
476 for (i = 0; i < ARRAY_SIZE(mem_types); i++)
477 mem_types[i].prot_sect &= ~PMD_SECT_TEX(7);
478 if ((cpu_arch < CPU_ARCH_ARMv6 || !(cr & CR_XP)) && !cpu_is_xsc3())
479 for (i = 0; i < ARRAY_SIZE(mem_types); i++)
480 mem_types[i].prot_sect &= ~PMD_SECT_S;
481
482 /*
483 * ARMv5 and lower, bit 4 must be set for page tables (was: cache
484 * "update-able on write" bit on ARM610). However, Xscale and
485 * Xscale3 require this bit to be cleared.
486 */
487 if (cpu_is_xscale_family()) {
488 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
489 mem_types[i].prot_sect &= ~PMD_BIT4;
490 mem_types[i].prot_l1 &= ~PMD_BIT4;
491 }
492 } else if (cpu_arch < CPU_ARCH_ARMv6) {
493 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
494 if (mem_types[i].prot_l1)
495 mem_types[i].prot_l1 |= PMD_BIT4;
496 if (mem_types[i].prot_sect)
497 mem_types[i].prot_sect |= PMD_BIT4;
498 }
499 }
500
501 /*
502 * Mark the device areas according to the CPU/architecture.
503 */
504 if (cpu_is_xsc3() || (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP))) {
505 if (!cpu_is_xsc3()) {
506 /*
507 * Mark device regions on ARMv6+ as execute-never
508 * to prevent speculative instruction fetches.
509 */
510 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_XN;
511 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_XN;
512 mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_XN;
513 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_XN;
514
515 /* Also setup NX memory mapping */
516 mem_types[MT_MEMORY_RW].prot_sect |= PMD_SECT_XN;
517 }
518 if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
519 /*
520 * For ARMv7 with TEX remapping,
521 * - shared device is SXCB=1100
522 * - nonshared device is SXCB=0100
523 * - write combine device mem is SXCB=0001
524 * (Uncached Normal memory)
525 */
526 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_TEX(1);
527 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(1);
528 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_BUFFERABLE;
529 } else if (cpu_is_xsc3()) {
530 /*
531 * For Xscale3,
532 * - shared device is TEXCB=00101
533 * - nonshared device is TEXCB=01000
534 * - write combine device mem is TEXCB=00100
535 * (Inner/Outer Uncacheable in xsc3 parlance)
536 */
537 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_TEX(1) | PMD_SECT_BUFFERED;
538 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(2);
539 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1);
540 } else {
541 /*
542 * For ARMv6 and ARMv7 without TEX remapping,
543 * - shared device is TEXCB=00001
544 * - nonshared device is TEXCB=01000
545 * - write combine device mem is TEXCB=00100
546 * (Uncached Normal in ARMv6 parlance).
547 */
548 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_BUFFERED;
549 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(2);
550 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1);
551 }
552 } else {
553 /*
554 * On others, write combining is "Uncached/Buffered"
555 */
556 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_BUFFERABLE;
557 }
558
559 /*
560 * Now deal with the memory-type mappings
561 */
562 cp = &cache_policies[cachepolicy];
563 vecs_pgprot = kern_pgprot = user_pgprot = cp->pte;
564 s2_pgprot = cp->pte_s2;
565 hyp_device_pgprot = mem_types[MT_DEVICE].prot_pte;
566 s2_device_pgprot = mem_types[MT_DEVICE].prot_pte_s2;
567
568#ifndef CONFIG_ARM_LPAE
569 /*
570 * We don't use domains on ARMv6 (since this causes problems with
571 * v6/v7 kernels), so we must use a separate memory type for user
572 * r/o, kernel r/w to map the vectors page.
573 */
574 if (cpu_arch == CPU_ARCH_ARMv6)
575 vecs_pgprot |= L_PTE_MT_VECTORS;
576
577 /*
578 * Check is it with support for the PXN bit
579 * in the Short-descriptor translation table format descriptors.
580 */
581 if (cpu_arch == CPU_ARCH_ARMv7 &&
582 (read_cpuid_ext(CPUID_EXT_MMFR0) & 0xF) >= 4) {
583 user_pmd_table |= PMD_PXNTABLE;
584 }
585#endif
586
587 /*
588 * ARMv6 and above have extended page tables.
589 */
590 if (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP)) {
591#ifndef CONFIG_ARM_LPAE
592 /*
593 * Mark cache clean areas and XIP ROM read only
594 * from SVC mode and no access from userspace.
595 */
596 mem_types[MT_ROM].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
597 mem_types[MT_MINICLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
598 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
599#endif
600
601 /*
602 * If the initial page tables were created with the S bit
603 * set, then we need to do the same here for the same
604 * reasons given in early_cachepolicy().
605 */
606 if (initial_pmd_value & PMD_SECT_S) {
607 user_pgprot |= L_PTE_SHARED;
608 kern_pgprot |= L_PTE_SHARED;
609 vecs_pgprot |= L_PTE_SHARED;
610 s2_pgprot |= L_PTE_SHARED;
611 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_S;
612 mem_types[MT_DEVICE_WC].prot_pte |= L_PTE_SHARED;
613 mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_S;
614 mem_types[MT_DEVICE_CACHED].prot_pte |= L_PTE_SHARED;
615 mem_types[MT_MEMORY_RWX].prot_sect |= PMD_SECT_S;
616 mem_types[MT_MEMORY_RWX].prot_pte |= L_PTE_SHARED;
617 mem_types[MT_MEMORY_RW].prot_sect |= PMD_SECT_S;
618 mem_types[MT_MEMORY_RW].prot_pte |= L_PTE_SHARED;
619 mem_types[MT_MEMORY_DMA_READY].prot_pte |= L_PTE_SHARED;
620 mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |= PMD_SECT_S;
621 mem_types[MT_MEMORY_RWX_NONCACHED].prot_pte |= L_PTE_SHARED;
622 }
623 }
624
625 /*
626 * Non-cacheable Normal - intended for memory areas that must
627 * not cause dirty cache line writebacks when used
628 */
629 if (cpu_arch >= CPU_ARCH_ARMv6) {
630 if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
631 /* Non-cacheable Normal is XCB = 001 */
632 mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |=
633 PMD_SECT_BUFFERED;
634 } else {
635 /* For both ARMv6 and non-TEX-remapping ARMv7 */
636 mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |=
637 PMD_SECT_TEX(1);
638 }
639 } else {
640 mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |= PMD_SECT_BUFFERABLE;
641 }
642
643#ifdef CONFIG_ARM_LPAE
644 /*
645 * Do not generate access flag faults for the kernel mappings.
646 */
647 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
648 mem_types[i].prot_pte |= PTE_EXT_AF;
649 if (mem_types[i].prot_sect)
650 mem_types[i].prot_sect |= PMD_SECT_AF;
651 }
652 kern_pgprot |= PTE_EXT_AF;
653 vecs_pgprot |= PTE_EXT_AF;
654
655 /*
656 * Set PXN for user mappings
657 */
658 user_pgprot |= PTE_EXT_PXN;
659#endif
660
661 for (i = 0; i < 16; i++) {
662 pteval_t v = pgprot_val(protection_map[i]);
663 protection_map[i] = __pgprot(v | user_pgprot);
664 }
665
666 mem_types[MT_LOW_VECTORS].prot_pte |= vecs_pgprot;
667 mem_types[MT_HIGH_VECTORS].prot_pte |= vecs_pgprot;
668
669 pgprot_user = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | user_pgprot);
670 pgprot_kernel = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG |
671 L_PTE_DIRTY | kern_pgprot);
672 pgprot_s2 = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | s2_pgprot);
673 pgprot_s2_device = __pgprot(s2_device_pgprot);
674 pgprot_hyp_device = __pgprot(hyp_device_pgprot);
675
676 mem_types[MT_LOW_VECTORS].prot_l1 |= ecc_mask;
677 mem_types[MT_HIGH_VECTORS].prot_l1 |= ecc_mask;
678 mem_types[MT_MEMORY_RWX].prot_sect |= ecc_mask | cp->pmd;
679 mem_types[MT_MEMORY_RWX].prot_pte |= kern_pgprot;
680 mem_types[MT_MEMORY_RW].prot_sect |= ecc_mask | cp->pmd;
681 mem_types[MT_MEMORY_RW].prot_pte |= kern_pgprot;
682 mem_types[MT_MEMORY_DMA_READY].prot_pte |= kern_pgprot;
683 mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |= ecc_mask;
684 mem_types[MT_ROM].prot_sect |= cp->pmd;
685
686 switch (cp->pmd) {
687 case PMD_SECT_WT:
688 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WT;
689 break;
690 case PMD_SECT_WB:
691 case PMD_SECT_WBWA:
692 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WB;
693 break;
694 }
695 pr_info("Memory policy: %sData cache %s\n",
696 ecc_mask ? "ECC enabled, " : "", cp->policy);
697
698 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
699 struct mem_type *t = &mem_types[i];
700 if (t->prot_l1)
701 t->prot_l1 |= PMD_DOMAIN(t->domain);
702 if (t->prot_sect)
703 t->prot_sect |= PMD_DOMAIN(t->domain);
704 }
705}
706
707#ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
708pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
709 unsigned long size, pgprot_t vma_prot)
710{
711 if (!pfn_valid(pfn))
712 return pgprot_noncached(vma_prot);
713 else if (file->f_flags & O_SYNC)
714 return pgprot_writecombine(vma_prot);
715 return vma_prot;
716}
717EXPORT_SYMBOL(phys_mem_access_prot);
718#endif
719
720#define vectors_base() (vectors_high() ? 0xffff0000 : 0)
721
722static void __init *early_alloc_aligned(unsigned long sz, unsigned long align)
723{
724 void *ptr = __va(memblock_alloc(sz, align));
725 memset(ptr, 0, sz);
726 return ptr;
727}
728
729static void __init *early_alloc(unsigned long sz)
730{
731 return early_alloc_aligned(sz, sz);
732}
733
734static void *__init late_alloc(unsigned long sz)
735{
736 void *ptr = (void *)__get_free_pages(PGALLOC_GFP, get_order(sz));
737
738 if (!ptr || !pgtable_page_ctor(virt_to_page(ptr)))
739 BUG();
740 return ptr;
741}
742
743static pte_t * __init arm_pte_alloc(pmd_t *pmd, unsigned long addr,
744 unsigned long prot,
745 void *(*alloc)(unsigned long sz))
746{
747 if (pmd_none(*pmd)) {
748 pte_t *pte = alloc(PTE_HWTABLE_OFF + PTE_HWTABLE_SIZE);
749 __pmd_populate(pmd, __pa(pte), prot);
750 }
751 BUG_ON(pmd_bad(*pmd));
752 return pte_offset_kernel(pmd, addr);
753}
754
755static pte_t * __init early_pte_alloc(pmd_t *pmd, unsigned long addr,
756 unsigned long prot)
757{
758 return arm_pte_alloc(pmd, addr, prot, early_alloc);
759}
760
761static void __init alloc_init_pte(pmd_t *pmd, unsigned long addr,
762 unsigned long end, unsigned long pfn,
763 const struct mem_type *type,
764 void *(*alloc)(unsigned long sz),
765 bool ng)
766{
767 pte_t *pte = arm_pte_alloc(pmd, addr, type->prot_l1, alloc);
768 do {
769 set_pte_ext(pte, pfn_pte(pfn, __pgprot(type->prot_pte)),
770 ng ? PTE_EXT_NG : 0);
771 pfn++;
772 } while (pte++, addr += PAGE_SIZE, addr != end);
773}
774
775static void __init __map_init_section(pmd_t *pmd, unsigned long addr,
776 unsigned long end, phys_addr_t phys,
777 const struct mem_type *type, bool ng)
778{
779 pmd_t *p = pmd;
780
781#ifndef CONFIG_ARM_LPAE
782 /*
783 * In classic MMU format, puds and pmds are folded in to
784 * the pgds. pmd_offset gives the PGD entry. PGDs refer to a
785 * group of L1 entries making up one logical pointer to
786 * an L2 table (2MB), where as PMDs refer to the individual
787 * L1 entries (1MB). Hence increment to get the correct
788 * offset for odd 1MB sections.
789 * (See arch/arm/include/asm/pgtable-2level.h)
790 */
791 if (addr & SECTION_SIZE)
792 pmd++;
793#endif
794 do {
795 *pmd = __pmd(phys | type->prot_sect | (ng ? PMD_SECT_nG : 0));
796 phys += SECTION_SIZE;
797 } while (pmd++, addr += SECTION_SIZE, addr != end);
798
799 flush_pmd_entry(p);
800}
801
802static void __init alloc_init_pmd(pud_t *pud, unsigned long addr,
803 unsigned long end, phys_addr_t phys,
804 const struct mem_type *type,
805 void *(*alloc)(unsigned long sz), bool ng)
806{
807 pmd_t *pmd = pmd_offset(pud, addr);
808 unsigned long next;
809
810 do {
811 /*
812 * With LPAE, we must loop over to map
813 * all the pmds for the given range.
814 */
815 next = pmd_addr_end(addr, end);
816
817 /*
818 * Try a section mapping - addr, next and phys must all be
819 * aligned to a section boundary.
820 */
821 if (type->prot_sect &&
822 ((addr | next | phys) & ~SECTION_MASK) == 0) {
823 __map_init_section(pmd, addr, next, phys, type, ng);
824 } else {
825 alloc_init_pte(pmd, addr, next,
826 __phys_to_pfn(phys), type, alloc, ng);
827 }
828
829 phys += next - addr;
830
831 } while (pmd++, addr = next, addr != end);
832}
833
834static void __init alloc_init_pud(pgd_t *pgd, unsigned long addr,
835 unsigned long end, phys_addr_t phys,
836 const struct mem_type *type,
837 void *(*alloc)(unsigned long sz), bool ng)
838{
839 pud_t *pud = pud_offset(pgd, addr);
840 unsigned long next;
841
842 do {
843 next = pud_addr_end(addr, end);
844 alloc_init_pmd(pud, addr, next, phys, type, alloc, ng);
845 phys += next - addr;
846 } while (pud++, addr = next, addr != end);
847}
848
849#ifndef CONFIG_ARM_LPAE
850static void __init create_36bit_mapping(struct mm_struct *mm,
851 struct map_desc *md,
852 const struct mem_type *type,
853 bool ng)
854{
855 unsigned long addr, length, end;
856 phys_addr_t phys;
857 pgd_t *pgd;
858
859 addr = md->virtual;
860 phys = __pfn_to_phys(md->pfn);
861 length = PAGE_ALIGN(md->length);
862
863 if (!(cpu_architecture() >= CPU_ARCH_ARMv6 || cpu_is_xsc3())) {
864 pr_err("MM: CPU does not support supersection mapping for 0x%08llx at 0x%08lx\n",
865 (long long)__pfn_to_phys((u64)md->pfn), addr);
866 return;
867 }
868
869 /* N.B. ARMv6 supersections are only defined to work with domain 0.
870 * Since domain assignments can in fact be arbitrary, the
871 * 'domain == 0' check below is required to insure that ARMv6
872 * supersections are only allocated for domain 0 regardless
873 * of the actual domain assignments in use.
874 */
875 if (type->domain) {
876 pr_err("MM: invalid domain in supersection mapping for 0x%08llx at 0x%08lx\n",
877 (long long)__pfn_to_phys((u64)md->pfn), addr);
878 return;
879 }
880
881 if ((addr | length | __pfn_to_phys(md->pfn)) & ~SUPERSECTION_MASK) {
882 pr_err("MM: cannot create mapping for 0x%08llx at 0x%08lx invalid alignment\n",
883 (long long)__pfn_to_phys((u64)md->pfn), addr);
884 return;
885 }
886
887 /*
888 * Shift bits [35:32] of address into bits [23:20] of PMD
889 * (See ARMv6 spec).
890 */
891 phys |= (((md->pfn >> (32 - PAGE_SHIFT)) & 0xF) << 20);
892
893 pgd = pgd_offset(mm, addr);
894 end = addr + length;
895 do {
896 pud_t *pud = pud_offset(pgd, addr);
897 pmd_t *pmd = pmd_offset(pud, addr);
898 int i;
899
900 for (i = 0; i < 16; i++)
901 *pmd++ = __pmd(phys | type->prot_sect | PMD_SECT_SUPER |
902 (ng ? PMD_SECT_nG : 0));
903
904 addr += SUPERSECTION_SIZE;
905 phys += SUPERSECTION_SIZE;
906 pgd += SUPERSECTION_SIZE >> PGDIR_SHIFT;
907 } while (addr != end);
908}
909#endif /* !CONFIG_ARM_LPAE */
910
911static void __init __create_mapping(struct mm_struct *mm, struct map_desc *md,
912 void *(*alloc)(unsigned long sz),
913 bool ng)
914{
915 unsigned long addr, length, end;
916 phys_addr_t phys;
917 const struct mem_type *type;
918 pgd_t *pgd;
919
920 type = &mem_types[md->type];
921
922#ifndef CONFIG_ARM_LPAE
923 /*
924 * Catch 36-bit addresses
925 */
926 if (md->pfn >= 0x100000) {
927 create_36bit_mapping(mm, md, type, ng);
928 return;
929 }
930#endif
931
932 addr = md->virtual & PAGE_MASK;
933 phys = __pfn_to_phys(md->pfn);
934 length = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK));
935
936 if (type->prot_l1 == 0 && ((addr | phys | length) & ~SECTION_MASK)) {
937 pr_warn("BUG: map for 0x%08llx at 0x%08lx can not be mapped using pages, ignoring.\n",
938 (long long)__pfn_to_phys(md->pfn), addr);
939 return;
940 }
941
942 pgd = pgd_offset(mm, addr);
943 end = addr + length;
944 do {
945 unsigned long next = pgd_addr_end(addr, end);
946
947 alloc_init_pud(pgd, addr, next, phys, type, alloc, ng);
948
949 phys += next - addr;
950 addr = next;
951 } while (pgd++, addr != end);
952}
953
954/*
955 * Create the page directory entries and any necessary
956 * page tables for the mapping specified by `md'. We
957 * are able to cope here with varying sizes and address
958 * offsets, and we take full advantage of sections and
959 * supersections.
960 */
961static void __init create_mapping(struct map_desc *md)
962{
963 if (md->virtual != vectors_base() && md->virtual < TASK_SIZE) {
964 pr_warn("BUG: not creating mapping for 0x%08llx at 0x%08lx in user region\n",
965 (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
966 return;
967 }
968
969 if ((md->type == MT_DEVICE || md->type == MT_ROM) &&
970 md->virtual >= PAGE_OFFSET && md->virtual < FIXADDR_START &&
971 (md->virtual < VMALLOC_START || md->virtual >= VMALLOC_END)) {
972 pr_warn("BUG: mapping for 0x%08llx at 0x%08lx out of vmalloc space\n",
973 (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
974 }
975
976 __create_mapping(&init_mm, md, early_alloc, false);
977}
978
979void __init create_mapping_late(struct mm_struct *mm, struct map_desc *md,
980 bool ng)
981{
982#ifdef CONFIG_ARM_LPAE
983 pud_t *pud = pud_alloc(mm, pgd_offset(mm, md->virtual), md->virtual);
984 if (WARN_ON(!pud))
985 return;
986 pmd_alloc(mm, pud, 0);
987#endif
988 __create_mapping(mm, md, late_alloc, ng);
989}
990
991/*
992 * Create the architecture specific mappings
993 */
994void __init iotable_init(struct map_desc *io_desc, int nr)
995{
996 struct map_desc *md;
997 struct vm_struct *vm;
998 struct static_vm *svm;
999
1000 if (!nr)
1001 return;
1002
1003 svm = early_alloc_aligned(sizeof(*svm) * nr, __alignof__(*svm));
1004
1005 for (md = io_desc; nr; md++, nr--) {
1006 create_mapping(md);
1007
1008 vm = &svm->vm;
1009 vm->addr = (void *)(md->virtual & PAGE_MASK);
1010 vm->size = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK));
1011 vm->phys_addr = __pfn_to_phys(md->pfn);
1012 vm->flags = VM_IOREMAP | VM_ARM_STATIC_MAPPING;
1013 vm->flags |= VM_ARM_MTYPE(md->type);
1014 vm->caller = iotable_init;
1015 add_static_vm_early(svm++);
1016 }
1017}
1018
1019void __init vm_reserve_area_early(unsigned long addr, unsigned long size,
1020 void *caller)
1021{
1022 struct vm_struct *vm;
1023 struct static_vm *svm;
1024
1025 svm = early_alloc_aligned(sizeof(*svm), __alignof__(*svm));
1026
1027 vm = &svm->vm;
1028 vm->addr = (void *)addr;
1029 vm->size = size;
1030 vm->flags = VM_IOREMAP | VM_ARM_EMPTY_MAPPING;
1031 vm->caller = caller;
1032 add_static_vm_early(svm);
1033}
1034
1035#ifndef CONFIG_ARM_LPAE
1036
1037/*
1038 * The Linux PMD is made of two consecutive section entries covering 2MB
1039 * (see definition in include/asm/pgtable-2level.h). However a call to
1040 * create_mapping() may optimize static mappings by using individual
1041 * 1MB section mappings. This leaves the actual PMD potentially half
1042 * initialized if the top or bottom section entry isn't used, leaving it
1043 * open to problems if a subsequent ioremap() or vmalloc() tries to use
1044 * the virtual space left free by that unused section entry.
1045 *
1046 * Let's avoid the issue by inserting dummy vm entries covering the unused
1047 * PMD halves once the static mappings are in place.
1048 */
1049
1050static void __init pmd_empty_section_gap(unsigned long addr)
1051{
1052 vm_reserve_area_early(addr, SECTION_SIZE, pmd_empty_section_gap);
1053}
1054
1055static void __init fill_pmd_gaps(void)
1056{
1057 struct static_vm *svm;
1058 struct vm_struct *vm;
1059 unsigned long addr, next = 0;
1060 pmd_t *pmd;
1061
1062 list_for_each_entry(svm, &static_vmlist, list) {
1063 vm = &svm->vm;
1064 addr = (unsigned long)vm->addr;
1065 if (addr < next)
1066 continue;
1067
1068 /*
1069 * Check if this vm starts on an odd section boundary.
1070 * If so and the first section entry for this PMD is free
1071 * then we block the corresponding virtual address.
1072 */
1073 if ((addr & ~PMD_MASK) == SECTION_SIZE) {
1074 pmd = pmd_off_k(addr);
1075 if (pmd_none(*pmd))
1076 pmd_empty_section_gap(addr & PMD_MASK);
1077 }
1078
1079 /*
1080 * Then check if this vm ends on an odd section boundary.
1081 * If so and the second section entry for this PMD is empty
1082 * then we block the corresponding virtual address.
1083 */
1084 addr += vm->size;
1085 if ((addr & ~PMD_MASK) == SECTION_SIZE) {
1086 pmd = pmd_off_k(addr) + 1;
1087 if (pmd_none(*pmd))
1088 pmd_empty_section_gap(addr);
1089 }
1090
1091 /* no need to look at any vm entry until we hit the next PMD */
1092 next = (addr + PMD_SIZE - 1) & PMD_MASK;
1093 }
1094}
1095
1096#else
1097#define fill_pmd_gaps() do { } while (0)
1098#endif
1099
1100#if defined(CONFIG_PCI) && !defined(CONFIG_NEED_MACH_IO_H)
1101static void __init pci_reserve_io(void)
1102{
1103 struct static_vm *svm;
1104
1105 svm = find_static_vm_vaddr((void *)PCI_IO_VIRT_BASE);
1106 if (svm)
1107 return;
1108
1109 vm_reserve_area_early(PCI_IO_VIRT_BASE, SZ_2M, pci_reserve_io);
1110}
1111#else
1112#define pci_reserve_io() do { } while (0)
1113#endif
1114
1115#ifdef CONFIG_DEBUG_LL
1116void __init debug_ll_io_init(void)
1117{
1118 struct map_desc map;
1119
1120 debug_ll_addr(&map.pfn, &map.virtual);
1121 if (!map.pfn || !map.virtual)
1122 return;
1123 map.pfn = __phys_to_pfn(map.pfn);
1124 map.virtual &= PAGE_MASK;
1125 map.length = PAGE_SIZE;
1126 map.type = MT_DEVICE;
1127 iotable_init(&map, 1);
1128}
1129#endif
1130
1131static void * __initdata vmalloc_min =
1132 (void *)(VMALLOC_END - (240 << 20) - VMALLOC_OFFSET);
1133
1134/*
1135 * vmalloc=size forces the vmalloc area to be exactly 'size'
1136 * bytes. This can be used to increase (or decrease) the vmalloc
1137 * area - the default is 240m.
1138 */
1139static int __init early_vmalloc(char *arg)
1140{
1141 unsigned long vmalloc_reserve = memparse(arg, NULL);
1142
1143 if (vmalloc_reserve < SZ_16M) {
1144 vmalloc_reserve = SZ_16M;
1145 pr_warn("vmalloc area too small, limiting to %luMB\n",
1146 vmalloc_reserve >> 20);
1147 }
1148
1149 if (vmalloc_reserve > VMALLOC_END - (PAGE_OFFSET + SZ_32M)) {
1150 vmalloc_reserve = VMALLOC_END - (PAGE_OFFSET + SZ_32M);
1151 pr_warn("vmalloc area is too big, limiting to %luMB\n",
1152 vmalloc_reserve >> 20);
1153 }
1154
1155 vmalloc_min = (void *)(VMALLOC_END - vmalloc_reserve);
1156 return 0;
1157}
1158early_param("vmalloc", early_vmalloc);
1159
1160phys_addr_t arm_lowmem_limit __initdata = 0;
1161
1162void __init adjust_lowmem_bounds(void)
1163{
1164 phys_addr_t memblock_limit = 0;
1165 u64 vmalloc_limit;
1166 struct memblock_region *reg;
1167 phys_addr_t lowmem_limit = 0;
1168
1169 /*
1170 * Let's use our own (unoptimized) equivalent of __pa() that is
1171 * not affected by wrap-arounds when sizeof(phys_addr_t) == 4.
1172 * The result is used as the upper bound on physical memory address
1173 * and may itself be outside the valid range for which phys_addr_t
1174 * and therefore __pa() is defined.
1175 */
1176 vmalloc_limit = (u64)(uintptr_t)vmalloc_min - PAGE_OFFSET + PHYS_OFFSET;
1177
1178 for_each_memblock(memory, reg) {
1179 phys_addr_t block_start = reg->base;
1180 phys_addr_t block_end = reg->base + reg->size;
1181
1182 if (reg->base < vmalloc_limit) {
1183 if (block_end > lowmem_limit)
1184 /*
1185 * Compare as u64 to ensure vmalloc_limit does
1186 * not get truncated. block_end should always
1187 * fit in phys_addr_t so there should be no
1188 * issue with assignment.
1189 */
1190 lowmem_limit = min_t(u64,
1191 vmalloc_limit,
1192 block_end);
1193
1194 /*
1195 * Find the first non-pmd-aligned page, and point
1196 * memblock_limit at it. This relies on rounding the
1197 * limit down to be pmd-aligned, which happens at the
1198 * end of this function.
1199 *
1200 * With this algorithm, the start or end of almost any
1201 * bank can be non-pmd-aligned. The only exception is
1202 * that the start of the bank 0 must be section-
1203 * aligned, since otherwise memory would need to be
1204 * allocated when mapping the start of bank 0, which
1205 * occurs before any free memory is mapped.
1206 */
1207 if (!memblock_limit) {
1208 if (!IS_ALIGNED(block_start, PMD_SIZE))
1209 memblock_limit = block_start;
1210 else if (!IS_ALIGNED(block_end, PMD_SIZE))
1211 memblock_limit = lowmem_limit;
1212 }
1213
1214 }
1215 }
1216
1217 arm_lowmem_limit = lowmem_limit;
1218
1219 high_memory = __va(arm_lowmem_limit - 1) + 1;
1220
1221 if (!memblock_limit)
1222 memblock_limit = arm_lowmem_limit;
1223
1224 /*
1225 * Round the memblock limit down to a pmd size. This
1226 * helps to ensure that we will allocate memory from the
1227 * last full pmd, which should be mapped.
1228 */
1229 memblock_limit = round_down(memblock_limit, PMD_SIZE);
1230
1231 if (!IS_ENABLED(CONFIG_HIGHMEM) || cache_is_vipt_aliasing()) {
1232 if (memblock_end_of_DRAM() > arm_lowmem_limit) {
1233 phys_addr_t end = memblock_end_of_DRAM();
1234
1235 pr_notice("Ignoring RAM at %pa-%pa\n",
1236 &memblock_limit, &end);
1237 pr_notice("Consider using a HIGHMEM enabled kernel.\n");
1238
1239 memblock_remove(memblock_limit, end - memblock_limit);
1240 }
1241 }
1242
1243 memblock_set_current_limit(memblock_limit);
1244}
1245
1246static inline void prepare_page_table(void)
1247{
1248 unsigned long addr;
1249 phys_addr_t end;
1250
1251 /*
1252 * Clear out all the mappings below the kernel image.
1253 */
1254 for (addr = 0; addr < MODULES_VADDR; addr += PMD_SIZE)
1255 pmd_clear(pmd_off_k(addr));
1256
1257#ifdef CONFIG_XIP_KERNEL
1258 /* The XIP kernel is mapped in the module area -- skip over it */
1259 addr = ((unsigned long)_exiprom + PMD_SIZE - 1) & PMD_MASK;
1260#endif
1261 for ( ; addr < PAGE_OFFSET; addr += PMD_SIZE)
1262 pmd_clear(pmd_off_k(addr));
1263
1264 /*
1265 * Find the end of the first block of lowmem.
1266 */
1267 end = memblock.memory.regions[0].base + memblock.memory.regions[0].size;
1268 if (end >= arm_lowmem_limit)
1269 end = arm_lowmem_limit;
1270
1271 /*
1272 * Clear out all the kernel space mappings, except for the first
1273 * memory bank, up to the vmalloc region.
1274 */
1275 for (addr = __phys_to_virt(end);
1276 addr < VMALLOC_START; addr += PMD_SIZE)
1277 pmd_clear(pmd_off_k(addr));
1278}
1279
1280#ifdef CONFIG_ARM_LPAE
1281/* the first page is reserved for pgd */
1282#define SWAPPER_PG_DIR_SIZE (PAGE_SIZE + \
1283 PTRS_PER_PGD * PTRS_PER_PMD * sizeof(pmd_t))
1284#else
1285#define SWAPPER_PG_DIR_SIZE (PTRS_PER_PGD * sizeof(pgd_t))
1286#endif
1287
1288/*
1289 * Reserve the special regions of memory
1290 */
1291void __init arm_mm_memblock_reserve(void)
1292{
1293 /*
1294 * Reserve the page tables. These are already in use,
1295 * and can only be in node 0.
1296 */
1297 memblock_reserve(__pa(swapper_pg_dir), SWAPPER_PG_DIR_SIZE);
1298
1299#ifdef CONFIG_SA1111
1300 /*
1301 * Because of the SA1111 DMA bug, we want to preserve our
1302 * precious DMA-able memory...
1303 */
1304 memblock_reserve(PHYS_OFFSET, __pa(swapper_pg_dir) - PHYS_OFFSET);
1305#endif
1306}
1307
1308/*
1309 * Set up the device mappings. Since we clear out the page tables for all
1310 * mappings above VMALLOC_START, except early fixmap, we might remove debug
1311 * device mappings. This means earlycon can be used to debug this function
1312 * Any other function or debugging method which may touch any device _will_
1313 * crash the kernel.
1314 */
1315static void __init devicemaps_init(const struct machine_desc *mdesc)
1316{
1317 struct map_desc map;
1318 unsigned long addr;
1319 void *vectors;
1320
1321 /*
1322 * Allocate the vector page early.
1323 */
1324 vectors = early_alloc(PAGE_SIZE * 2);
1325
1326 early_trap_init(vectors);
1327
1328 /*
1329 * Clear page table except top pmd used by early fixmaps
1330 */
1331 for (addr = VMALLOC_START; addr < (FIXADDR_TOP & PMD_MASK); addr += PMD_SIZE)
1332 pmd_clear(pmd_off_k(addr));
1333
1334 /*
1335 * Map the kernel if it is XIP.
1336 * It is always first in the modulearea.
1337 */
1338#ifdef CONFIG_XIP_KERNEL
1339 map.pfn = __phys_to_pfn(CONFIG_XIP_PHYS_ADDR & SECTION_MASK);
1340 map.virtual = MODULES_VADDR;
1341 map.length = ((unsigned long)_exiprom - map.virtual + ~SECTION_MASK) & SECTION_MASK;
1342 map.type = MT_ROM;
1343 create_mapping(&map);
1344#endif
1345
1346 /*
1347 * Map the cache flushing regions.
1348 */
1349#ifdef FLUSH_BASE
1350 map.pfn = __phys_to_pfn(FLUSH_BASE_PHYS);
1351 map.virtual = FLUSH_BASE;
1352 map.length = SZ_1M;
1353 map.type = MT_CACHECLEAN;
1354 create_mapping(&map);
1355#endif
1356#ifdef FLUSH_BASE_MINICACHE
1357 map.pfn = __phys_to_pfn(FLUSH_BASE_PHYS + SZ_1M);
1358 map.virtual = FLUSH_BASE_MINICACHE;
1359 map.length = SZ_1M;
1360 map.type = MT_MINICLEAN;
1361 create_mapping(&map);
1362#endif
1363
1364 /*
1365 * Create a mapping for the machine vectors at the high-vectors
1366 * location (0xffff0000). If we aren't using high-vectors, also
1367 * create a mapping at the low-vectors virtual address.
1368 */
1369 map.pfn = __phys_to_pfn(virt_to_phys(vectors));
1370 map.virtual = 0xffff0000;
1371 map.length = PAGE_SIZE;
1372#ifdef CONFIG_KUSER_HELPERS
1373 map.type = MT_HIGH_VECTORS;
1374#else
1375 map.type = MT_LOW_VECTORS;
1376#endif
1377 create_mapping(&map);
1378
1379 if (!vectors_high()) {
1380 map.virtual = 0;
1381 map.length = PAGE_SIZE * 2;
1382 map.type = MT_LOW_VECTORS;
1383 create_mapping(&map);
1384 }
1385
1386 /* Now create a kernel read-only mapping */
1387 map.pfn += 1;
1388 map.virtual = 0xffff0000 + PAGE_SIZE;
1389 map.length = PAGE_SIZE;
1390 map.type = MT_LOW_VECTORS;
1391 create_mapping(&map);
1392
1393 /*
1394 * Ask the machine support to map in the statically mapped devices.
1395 */
1396 if (mdesc->map_io)
1397 mdesc->map_io();
1398 else
1399 debug_ll_io_init();
1400 fill_pmd_gaps();
1401
1402 /* Reserve fixed i/o space in VMALLOC region */
1403 pci_reserve_io();
1404
1405 /*
1406 * Finally flush the caches and tlb to ensure that we're in a
1407 * consistent state wrt the writebuffer. This also ensures that
1408 * any write-allocated cache lines in the vector page are written
1409 * back. After this point, we can start to touch devices again.
1410 */
1411 local_flush_tlb_all();
1412 flush_cache_all();
1413
1414 /* Enable asynchronous aborts */
1415 early_abt_enable();
1416}
1417
1418static void __init kmap_init(void)
1419{
1420#ifdef CONFIG_HIGHMEM
1421 pkmap_page_table = early_pte_alloc(pmd_off_k(PKMAP_BASE),
1422 PKMAP_BASE, _PAGE_KERNEL_TABLE);
1423#endif
1424
1425 early_pte_alloc(pmd_off_k(FIXADDR_START), FIXADDR_START,
1426 _PAGE_KERNEL_TABLE);
1427}
1428
1429static void __init map_lowmem(void)
1430{
1431 struct memblock_region *reg;
1432 phys_addr_t kernel_x_start = round_down(__pa(KERNEL_START), SECTION_SIZE);
1433 phys_addr_t kernel_x_end = round_up(__pa(__init_end), SECTION_SIZE);
1434
1435 /* Map all the lowmem memory banks. */
1436 for_each_memblock(memory, reg) {
1437 phys_addr_t start = reg->base;
1438 phys_addr_t end = start + reg->size;
1439 struct map_desc map;
1440
1441 if (memblock_is_nomap(reg))
1442 continue;
1443
1444 if (end > arm_lowmem_limit)
1445 end = arm_lowmem_limit;
1446 if (start >= end)
1447 break;
1448
1449 if (end < kernel_x_start) {
1450 map.pfn = __phys_to_pfn(start);
1451 map.virtual = __phys_to_virt(start);
1452 map.length = end - start;
1453 map.type = MT_MEMORY_RWX;
1454
1455 create_mapping(&map);
1456 } else if (start >= kernel_x_end) {
1457 map.pfn = __phys_to_pfn(start);
1458 map.virtual = __phys_to_virt(start);
1459 map.length = end - start;
1460 map.type = MT_MEMORY_RW;
1461
1462 create_mapping(&map);
1463 } else {
1464 /* This better cover the entire kernel */
1465 if (start < kernel_x_start) {
1466 map.pfn = __phys_to_pfn(start);
1467 map.virtual = __phys_to_virt(start);
1468 map.length = kernel_x_start - start;
1469 map.type = MT_MEMORY_RW;
1470
1471 create_mapping(&map);
1472 }
1473
1474 map.pfn = __phys_to_pfn(kernel_x_start);
1475 map.virtual = __phys_to_virt(kernel_x_start);
1476 map.length = kernel_x_end - kernel_x_start;
1477 map.type = MT_MEMORY_RWX;
1478
1479 create_mapping(&map);
1480
1481 if (kernel_x_end < end) {
1482 map.pfn = __phys_to_pfn(kernel_x_end);
1483 map.virtual = __phys_to_virt(kernel_x_end);
1484 map.length = end - kernel_x_end;
1485 map.type = MT_MEMORY_RW;
1486
1487 create_mapping(&map);
1488 }
1489 }
1490 }
1491}
1492
1493#ifdef CONFIG_ARM_PV_FIXUP
1494extern unsigned long __atags_pointer;
1495typedef void pgtables_remap(long long offset, unsigned long pgd, void *bdata);
1496pgtables_remap lpae_pgtables_remap_asm;
1497
1498/*
1499 * early_paging_init() recreates boot time page table setup, allowing machines
1500 * to switch over to a high (>4G) address space on LPAE systems
1501 */
1502static void __init early_paging_init(const struct machine_desc *mdesc)
1503{
1504 pgtables_remap *lpae_pgtables_remap;
1505 unsigned long pa_pgd;
1506 unsigned int cr, ttbcr;
1507 long long offset;
1508 void *boot_data;
1509
1510 if (!mdesc->pv_fixup)
1511 return;
1512
1513 offset = mdesc->pv_fixup();
1514 if (offset == 0)
1515 return;
1516
1517 /*
1518 * Get the address of the remap function in the 1:1 identity
1519 * mapping setup by the early page table assembly code. We
1520 * must get this prior to the pv update. The following barrier
1521 * ensures that this is complete before we fixup any P:V offsets.
1522 */
1523 lpae_pgtables_remap = (pgtables_remap *)(unsigned long)__pa(lpae_pgtables_remap_asm);
1524 pa_pgd = __pa(swapper_pg_dir);
1525 boot_data = __va(__atags_pointer);
1526 barrier();
1527
1528 pr_info("Switching physical address space to 0x%08llx\n",
1529 (u64)PHYS_OFFSET + offset);
1530
1531 /* Re-set the phys pfn offset, and the pv offset */
1532 __pv_offset += offset;
1533 __pv_phys_pfn_offset += PFN_DOWN(offset);
1534
1535 /* Run the patch stub to update the constants */
1536 fixup_pv_table(&__pv_table_begin,
1537 (&__pv_table_end - &__pv_table_begin) << 2);
1538
1539 /*
1540 * We changing not only the virtual to physical mapping, but also
1541 * the physical addresses used to access memory. We need to flush
1542 * all levels of cache in the system with caching disabled to
1543 * ensure that all data is written back, and nothing is prefetched
1544 * into the caches. We also need to prevent the TLB walkers
1545 * allocating into the caches too. Note that this is ARMv7 LPAE
1546 * specific.
1547 */
1548 cr = get_cr();
1549 set_cr(cr & ~(CR_I | CR_C));
1550 asm("mrc p15, 0, %0, c2, c0, 2" : "=r" (ttbcr));
1551 asm volatile("mcr p15, 0, %0, c2, c0, 2"
1552 : : "r" (ttbcr & ~(3 << 8 | 3 << 10)));
1553 flush_cache_all();
1554
1555 /*
1556 * Fixup the page tables - this must be in the idmap region as
1557 * we need to disable the MMU to do this safely, and hence it
1558 * needs to be assembly. It's fairly simple, as we're using the
1559 * temporary tables setup by the initial assembly code.
1560 */
1561 lpae_pgtables_remap(offset, pa_pgd, boot_data);
1562
1563 /* Re-enable the caches and cacheable TLB walks */
1564 asm volatile("mcr p15, 0, %0, c2, c0, 2" : : "r" (ttbcr));
1565 set_cr(cr);
1566}
1567
1568#else
1569
1570static void __init early_paging_init(const struct machine_desc *mdesc)
1571{
1572 long long offset;
1573
1574 if (!mdesc->pv_fixup)
1575 return;
1576
1577 offset = mdesc->pv_fixup();
1578 if (offset == 0)
1579 return;
1580
1581 pr_crit("Physical address space modification is only to support Keystone2.\n");
1582 pr_crit("Please enable ARM_LPAE and ARM_PATCH_PHYS_VIRT support to use this\n");
1583 pr_crit("feature. Your kernel may crash now, have a good day.\n");
1584 add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
1585}
1586
1587#endif
1588
1589static void __init early_fixmap_shutdown(void)
1590{
1591 int i;
1592 unsigned long va = fix_to_virt(__end_of_permanent_fixed_addresses - 1);
1593
1594 pte_offset_fixmap = pte_offset_late_fixmap;
1595 pmd_clear(fixmap_pmd(va));
1596 local_flush_tlb_kernel_page(va);
1597
1598 for (i = 0; i < __end_of_permanent_fixed_addresses; i++) {
1599 pte_t *pte;
1600 struct map_desc map;
1601
1602 map.virtual = fix_to_virt(i);
1603 pte = pte_offset_early_fixmap(pmd_off_k(map.virtual), map.virtual);
1604
1605 /* Only i/o device mappings are supported ATM */
1606 if (pte_none(*pte) ||
1607 (pte_val(*pte) & L_PTE_MT_MASK) != L_PTE_MT_DEV_SHARED)
1608 continue;
1609
1610 map.pfn = pte_pfn(*pte);
1611 map.type = MT_DEVICE;
1612 map.length = PAGE_SIZE;
1613
1614 create_mapping(&map);
1615 }
1616}
1617
1618/*
1619 * paging_init() sets up the page tables, initialises the zone memory
1620 * maps, and sets up the zero page, bad page and bad page tables.
1621 */
1622void __init paging_init(const struct machine_desc *mdesc)
1623{
1624 void *zero_page;
1625
1626 prepare_page_table();
1627 map_lowmem();
1628 memblock_set_current_limit(arm_lowmem_limit);
1629 dma_contiguous_remap();
1630 early_fixmap_shutdown();
1631 devicemaps_init(mdesc);
1632 kmap_init();
1633 tcm_init();
1634
1635 top_pmd = pmd_off_k(0xffff0000);
1636
1637 /* allocate the zero page. */
1638 zero_page = early_alloc(PAGE_SIZE);
1639
1640 bootmem_init();
1641
1642 empty_zero_page = virt_to_page(zero_page);
1643 __flush_dcache_page(NULL, empty_zero_page);
1644
1645 /* Compute the virt/idmap offset, mostly for the sake of KVM */
1646 kimage_voffset = (unsigned long)&kimage_voffset - virt_to_idmap(&kimage_voffset);
1647}
1648
1649void __init early_mm_init(const struct machine_desc *mdesc)
1650{
1651 build_mem_type_table();
1652 early_paging_init(mdesc);
1653}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/arch/arm/mm/mmu.c
4 *
5 * Copyright (C) 1995-2005 Russell King
6 */
7#include <linux/module.h>
8#include <linux/kernel.h>
9#include <linux/errno.h>
10#include <linux/init.h>
11#include <linux/mman.h>
12#include <linux/nodemask.h>
13#include <linux/memblock.h>
14#include <linux/fs.h>
15#include <linux/vmalloc.h>
16#include <linux/sizes.h>
17
18#include <asm/cp15.h>
19#include <asm/cputype.h>
20#include <asm/cachetype.h>
21#include <asm/sections.h>
22#include <asm/setup.h>
23#include <asm/smp_plat.h>
24#include <asm/tcm.h>
25#include <asm/tlb.h>
26#include <asm/highmem.h>
27#include <asm/system_info.h>
28#include <asm/traps.h>
29#include <asm/procinfo.h>
30#include <asm/page.h>
31#include <asm/pgalloc.h>
32#include <asm/kasan_def.h>
33
34#include <asm/mach/arch.h>
35#include <asm/mach/map.h>
36#include <asm/mach/pci.h>
37#include <asm/fixmap.h>
38
39#include "fault.h"
40#include "mm.h"
41
42extern unsigned long __atags_pointer;
43
44/*
45 * empty_zero_page is a special page that is used for
46 * zero-initialized data and COW.
47 */
48struct page *empty_zero_page;
49EXPORT_SYMBOL(empty_zero_page);
50
51/*
52 * The pmd table for the upper-most set of pages.
53 */
54pmd_t *top_pmd;
55
56pmdval_t user_pmd_table = _PAGE_USER_TABLE;
57
58#define CPOLICY_UNCACHED 0
59#define CPOLICY_BUFFERED 1
60#define CPOLICY_WRITETHROUGH 2
61#define CPOLICY_WRITEBACK 3
62#define CPOLICY_WRITEALLOC 4
63
64static unsigned int cachepolicy __initdata = CPOLICY_WRITEBACK;
65static unsigned int ecc_mask __initdata = 0;
66pgprot_t pgprot_user;
67pgprot_t pgprot_kernel;
68
69EXPORT_SYMBOL(pgprot_user);
70EXPORT_SYMBOL(pgprot_kernel);
71
72struct cachepolicy {
73 const char policy[16];
74 unsigned int cr_mask;
75 pmdval_t pmd;
76 pteval_t pte;
77};
78
79static struct cachepolicy cache_policies[] __initdata = {
80 {
81 .policy = "uncached",
82 .cr_mask = CR_W|CR_C,
83 .pmd = PMD_SECT_UNCACHED,
84 .pte = L_PTE_MT_UNCACHED,
85 }, {
86 .policy = "buffered",
87 .cr_mask = CR_C,
88 .pmd = PMD_SECT_BUFFERED,
89 .pte = L_PTE_MT_BUFFERABLE,
90 }, {
91 .policy = "writethrough",
92 .cr_mask = 0,
93 .pmd = PMD_SECT_WT,
94 .pte = L_PTE_MT_WRITETHROUGH,
95 }, {
96 .policy = "writeback",
97 .cr_mask = 0,
98 .pmd = PMD_SECT_WB,
99 .pte = L_PTE_MT_WRITEBACK,
100 }, {
101 .policy = "writealloc",
102 .cr_mask = 0,
103 .pmd = PMD_SECT_WBWA,
104 .pte = L_PTE_MT_WRITEALLOC,
105 }
106};
107
108#ifdef CONFIG_CPU_CP15
109static unsigned long initial_pmd_value __initdata = 0;
110
111/*
112 * Initialise the cache_policy variable with the initial state specified
113 * via the "pmd" value. This is used to ensure that on ARMv6 and later,
114 * the C code sets the page tables up with the same policy as the head
115 * assembly code, which avoids an illegal state where the TLBs can get
116 * confused. See comments in early_cachepolicy() for more information.
117 */
118void __init init_default_cache_policy(unsigned long pmd)
119{
120 int i;
121
122 initial_pmd_value = pmd;
123
124 pmd &= PMD_SECT_CACHE_MASK;
125
126 for (i = 0; i < ARRAY_SIZE(cache_policies); i++)
127 if (cache_policies[i].pmd == pmd) {
128 cachepolicy = i;
129 break;
130 }
131
132 if (i == ARRAY_SIZE(cache_policies))
133 pr_err("ERROR: could not find cache policy\n");
134}
135
136/*
137 * These are useful for identifying cache coherency problems by allowing
138 * the cache or the cache and writebuffer to be turned off. (Note: the
139 * write buffer should not be on and the cache off).
140 */
141static int __init early_cachepolicy(char *p)
142{
143 int i, selected = -1;
144
145 for (i = 0; i < ARRAY_SIZE(cache_policies); i++) {
146 int len = strlen(cache_policies[i].policy);
147
148 if (memcmp(p, cache_policies[i].policy, len) == 0) {
149 selected = i;
150 break;
151 }
152 }
153
154 if (selected == -1)
155 pr_err("ERROR: unknown or unsupported cache policy\n");
156
157 /*
158 * This restriction is partly to do with the way we boot; it is
159 * unpredictable to have memory mapped using two different sets of
160 * memory attributes (shared, type, and cache attribs). We can not
161 * change these attributes once the initial assembly has setup the
162 * page tables.
163 */
164 if (cpu_architecture() >= CPU_ARCH_ARMv6 && selected != cachepolicy) {
165 pr_warn("Only cachepolicy=%s supported on ARMv6 and later\n",
166 cache_policies[cachepolicy].policy);
167 return 0;
168 }
169
170 if (selected != cachepolicy) {
171 unsigned long cr = __clear_cr(cache_policies[selected].cr_mask);
172 cachepolicy = selected;
173 flush_cache_all();
174 set_cr(cr);
175 }
176 return 0;
177}
178early_param("cachepolicy", early_cachepolicy);
179
180static int __init early_nocache(char *__unused)
181{
182 char *p = "buffered";
183 pr_warn("nocache is deprecated; use cachepolicy=%s\n", p);
184 early_cachepolicy(p);
185 return 0;
186}
187early_param("nocache", early_nocache);
188
189static int __init early_nowrite(char *__unused)
190{
191 char *p = "uncached";
192 pr_warn("nowb is deprecated; use cachepolicy=%s\n", p);
193 early_cachepolicy(p);
194 return 0;
195}
196early_param("nowb", early_nowrite);
197
198#ifndef CONFIG_ARM_LPAE
199static int __init early_ecc(char *p)
200{
201 if (memcmp(p, "on", 2) == 0)
202 ecc_mask = PMD_PROTECTION;
203 else if (memcmp(p, "off", 3) == 0)
204 ecc_mask = 0;
205 return 0;
206}
207early_param("ecc", early_ecc);
208#endif
209
210#else /* ifdef CONFIG_CPU_CP15 */
211
212static int __init early_cachepolicy(char *p)
213{
214 pr_warn("cachepolicy kernel parameter not supported without cp15\n");
215 return 0;
216}
217early_param("cachepolicy", early_cachepolicy);
218
219static int __init noalign_setup(char *__unused)
220{
221 pr_warn("noalign kernel parameter not supported without cp15\n");
222 return 1;
223}
224__setup("noalign", noalign_setup);
225
226#endif /* ifdef CONFIG_CPU_CP15 / else */
227
228#define PROT_PTE_DEVICE L_PTE_PRESENT|L_PTE_YOUNG|L_PTE_DIRTY|L_PTE_XN
229#define PROT_PTE_S2_DEVICE PROT_PTE_DEVICE
230#define PROT_SECT_DEVICE PMD_TYPE_SECT|PMD_SECT_AP_WRITE
231
232static struct mem_type mem_types[] __ro_after_init = {
233 [MT_DEVICE] = { /* Strongly ordered / ARMv6 shared device */
234 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_SHARED |
235 L_PTE_SHARED,
236 .prot_l1 = PMD_TYPE_TABLE,
237 .prot_sect = PROT_SECT_DEVICE | PMD_SECT_S,
238 .domain = DOMAIN_IO,
239 },
240 [MT_DEVICE_NONSHARED] = { /* ARMv6 non-shared device */
241 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_NONSHARED,
242 .prot_l1 = PMD_TYPE_TABLE,
243 .prot_sect = PROT_SECT_DEVICE,
244 .domain = DOMAIN_IO,
245 },
246 [MT_DEVICE_CACHED] = { /* ioremap_cache */
247 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_CACHED,
248 .prot_l1 = PMD_TYPE_TABLE,
249 .prot_sect = PROT_SECT_DEVICE | PMD_SECT_WB,
250 .domain = DOMAIN_IO,
251 },
252 [MT_DEVICE_WC] = { /* ioremap_wc */
253 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_WC,
254 .prot_l1 = PMD_TYPE_TABLE,
255 .prot_sect = PROT_SECT_DEVICE,
256 .domain = DOMAIN_IO,
257 },
258 [MT_UNCACHED] = {
259 .prot_pte = PROT_PTE_DEVICE,
260 .prot_l1 = PMD_TYPE_TABLE,
261 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
262 .domain = DOMAIN_IO,
263 },
264 [MT_CACHECLEAN] = {
265 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
266 .domain = DOMAIN_KERNEL,
267 },
268#ifndef CONFIG_ARM_LPAE
269 [MT_MINICLEAN] = {
270 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN | PMD_SECT_MINICACHE,
271 .domain = DOMAIN_KERNEL,
272 },
273#endif
274 [MT_LOW_VECTORS] = {
275 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
276 L_PTE_RDONLY,
277 .prot_l1 = PMD_TYPE_TABLE,
278 .domain = DOMAIN_VECTORS,
279 },
280 [MT_HIGH_VECTORS] = {
281 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
282 L_PTE_USER | L_PTE_RDONLY,
283 .prot_l1 = PMD_TYPE_TABLE,
284 .domain = DOMAIN_VECTORS,
285 },
286 [MT_MEMORY_RWX] = {
287 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
288 .prot_l1 = PMD_TYPE_TABLE,
289 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
290 .domain = DOMAIN_KERNEL,
291 },
292 [MT_MEMORY_RW] = {
293 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
294 L_PTE_XN,
295 .prot_l1 = PMD_TYPE_TABLE,
296 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
297 .domain = DOMAIN_KERNEL,
298 },
299 [MT_MEMORY_RO] = {
300 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
301 L_PTE_XN | L_PTE_RDONLY,
302 .prot_l1 = PMD_TYPE_TABLE,
303#ifdef CONFIG_ARM_LPAE
304 .prot_sect = PMD_TYPE_SECT | L_PMD_SECT_RDONLY | PMD_SECT_AP2,
305#else
306 .prot_sect = PMD_TYPE_SECT,
307#endif
308 .domain = DOMAIN_KERNEL,
309 },
310 [MT_ROM] = {
311 .prot_sect = PMD_TYPE_SECT,
312 .domain = DOMAIN_KERNEL,
313 },
314 [MT_MEMORY_RWX_NONCACHED] = {
315 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
316 L_PTE_MT_BUFFERABLE,
317 .prot_l1 = PMD_TYPE_TABLE,
318 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
319 .domain = DOMAIN_KERNEL,
320 },
321 [MT_MEMORY_RW_DTCM] = {
322 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
323 L_PTE_XN,
324 .prot_l1 = PMD_TYPE_TABLE,
325 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
326 .domain = DOMAIN_KERNEL,
327 },
328 [MT_MEMORY_RWX_ITCM] = {
329 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
330 .prot_l1 = PMD_TYPE_TABLE,
331 .domain = DOMAIN_KERNEL,
332 },
333 [MT_MEMORY_RW_SO] = {
334 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
335 L_PTE_MT_UNCACHED | L_PTE_XN,
336 .prot_l1 = PMD_TYPE_TABLE,
337 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_SECT_S |
338 PMD_SECT_UNCACHED | PMD_SECT_XN,
339 .domain = DOMAIN_KERNEL,
340 },
341 [MT_MEMORY_DMA_READY] = {
342 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
343 L_PTE_XN,
344 .prot_l1 = PMD_TYPE_TABLE,
345 .domain = DOMAIN_KERNEL,
346 },
347};
348
349const struct mem_type *get_mem_type(unsigned int type)
350{
351 return type < ARRAY_SIZE(mem_types) ? &mem_types[type] : NULL;
352}
353EXPORT_SYMBOL(get_mem_type);
354
355static pte_t *(*pte_offset_fixmap)(pmd_t *dir, unsigned long addr);
356
357static pte_t bm_pte[PTRS_PER_PTE + PTE_HWTABLE_PTRS]
358 __aligned(PTE_HWTABLE_OFF + PTE_HWTABLE_SIZE) __initdata;
359
360static pte_t * __init pte_offset_early_fixmap(pmd_t *dir, unsigned long addr)
361{
362 return &bm_pte[pte_index(addr)];
363}
364
365static pte_t *pte_offset_late_fixmap(pmd_t *dir, unsigned long addr)
366{
367 return pte_offset_kernel(dir, addr);
368}
369
370static inline pmd_t * __init fixmap_pmd(unsigned long addr)
371{
372 return pmd_off_k(addr);
373}
374
375void __init early_fixmap_init(void)
376{
377 pmd_t *pmd;
378
379 /*
380 * The early fixmap range spans multiple pmds, for which
381 * we are not prepared:
382 */
383 BUILD_BUG_ON((__fix_to_virt(__end_of_early_ioremap_region) >> PMD_SHIFT)
384 != FIXADDR_TOP >> PMD_SHIFT);
385
386 pmd = fixmap_pmd(FIXADDR_TOP);
387 pmd_populate_kernel(&init_mm, pmd, bm_pte);
388
389 pte_offset_fixmap = pte_offset_early_fixmap;
390}
391
392/*
393 * To avoid TLB flush broadcasts, this uses local_flush_tlb_kernel_range().
394 * As a result, this can only be called with preemption disabled, as under
395 * stop_machine().
396 */
397void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
398{
399 unsigned long vaddr = __fix_to_virt(idx);
400 pte_t *pte = pte_offset_fixmap(pmd_off_k(vaddr), vaddr);
401
402 /* Make sure fixmap region does not exceed available allocation. */
403 BUILD_BUG_ON(__fix_to_virt(__end_of_fixed_addresses) < FIXADDR_START);
404 BUG_ON(idx >= __end_of_fixed_addresses);
405
406 /* We support only device mappings before pgprot_kernel is set. */
407 if (WARN_ON(pgprot_val(prot) != pgprot_val(FIXMAP_PAGE_IO) &&
408 pgprot_val(prot) && pgprot_val(pgprot_kernel) == 0))
409 return;
410
411 if (pgprot_val(prot))
412 set_pte_at(NULL, vaddr, pte,
413 pfn_pte(phys >> PAGE_SHIFT, prot));
414 else
415 pte_clear(NULL, vaddr, pte);
416 local_flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE);
417}
418
419static pgprot_t protection_map[16] __ro_after_init = {
420 [VM_NONE] = __PAGE_NONE,
421 [VM_READ] = __PAGE_READONLY,
422 [VM_WRITE] = __PAGE_COPY,
423 [VM_WRITE | VM_READ] = __PAGE_COPY,
424 [VM_EXEC] = __PAGE_READONLY_EXEC,
425 [VM_EXEC | VM_READ] = __PAGE_READONLY_EXEC,
426 [VM_EXEC | VM_WRITE] = __PAGE_COPY_EXEC,
427 [VM_EXEC | VM_WRITE | VM_READ] = __PAGE_COPY_EXEC,
428 [VM_SHARED] = __PAGE_NONE,
429 [VM_SHARED | VM_READ] = __PAGE_READONLY,
430 [VM_SHARED | VM_WRITE] = __PAGE_SHARED,
431 [VM_SHARED | VM_WRITE | VM_READ] = __PAGE_SHARED,
432 [VM_SHARED | VM_EXEC] = __PAGE_READONLY_EXEC,
433 [VM_SHARED | VM_EXEC | VM_READ] = __PAGE_READONLY_EXEC,
434 [VM_SHARED | VM_EXEC | VM_WRITE] = __PAGE_SHARED_EXEC,
435 [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = __PAGE_SHARED_EXEC
436};
437DECLARE_VM_GET_PAGE_PROT
438
439/*
440 * Adjust the PMD section entries according to the CPU in use.
441 */
442static void __init build_mem_type_table(void)
443{
444 struct cachepolicy *cp;
445 unsigned int cr = get_cr();
446 pteval_t user_pgprot, kern_pgprot, vecs_pgprot;
447 int cpu_arch = cpu_architecture();
448 int i;
449
450 if (cpu_arch < CPU_ARCH_ARMv6) {
451#if defined(CONFIG_CPU_DCACHE_DISABLE)
452 if (cachepolicy > CPOLICY_BUFFERED)
453 cachepolicy = CPOLICY_BUFFERED;
454#elif defined(CONFIG_CPU_DCACHE_WRITETHROUGH)
455 if (cachepolicy > CPOLICY_WRITETHROUGH)
456 cachepolicy = CPOLICY_WRITETHROUGH;
457#endif
458 }
459 if (cpu_arch < CPU_ARCH_ARMv5) {
460 if (cachepolicy >= CPOLICY_WRITEALLOC)
461 cachepolicy = CPOLICY_WRITEBACK;
462 ecc_mask = 0;
463 }
464
465 if (is_smp()) {
466 if (cachepolicy != CPOLICY_WRITEALLOC) {
467 pr_warn("Forcing write-allocate cache policy for SMP\n");
468 cachepolicy = CPOLICY_WRITEALLOC;
469 }
470 if (!(initial_pmd_value & PMD_SECT_S)) {
471 pr_warn("Forcing shared mappings for SMP\n");
472 initial_pmd_value |= PMD_SECT_S;
473 }
474 }
475
476 /*
477 * Strip out features not present on earlier architectures.
478 * Pre-ARMv5 CPUs don't have TEX bits. Pre-ARMv6 CPUs or those
479 * without extended page tables don't have the 'Shared' bit.
480 */
481 if (cpu_arch < CPU_ARCH_ARMv5)
482 for (i = 0; i < ARRAY_SIZE(mem_types); i++)
483 mem_types[i].prot_sect &= ~PMD_SECT_TEX(7);
484 if ((cpu_arch < CPU_ARCH_ARMv6 || !(cr & CR_XP)) && !cpu_is_xsc3())
485 for (i = 0; i < ARRAY_SIZE(mem_types); i++)
486 mem_types[i].prot_sect &= ~PMD_SECT_S;
487
488 /*
489 * ARMv5 and lower, bit 4 must be set for page tables (was: cache
490 * "update-able on write" bit on ARM610). However, Xscale and
491 * Xscale3 require this bit to be cleared.
492 */
493 if (cpu_is_xscale_family()) {
494 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
495 mem_types[i].prot_sect &= ~PMD_BIT4;
496 mem_types[i].prot_l1 &= ~PMD_BIT4;
497 }
498 } else if (cpu_arch < CPU_ARCH_ARMv6) {
499 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
500 if (mem_types[i].prot_l1)
501 mem_types[i].prot_l1 |= PMD_BIT4;
502 if (mem_types[i].prot_sect)
503 mem_types[i].prot_sect |= PMD_BIT4;
504 }
505 }
506
507 /*
508 * Mark the device areas according to the CPU/architecture.
509 */
510 if (cpu_is_xsc3() || (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP))) {
511 if (!cpu_is_xsc3()) {
512 /*
513 * Mark device regions on ARMv6+ as execute-never
514 * to prevent speculative instruction fetches.
515 */
516 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_XN;
517 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_XN;
518 mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_XN;
519 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_XN;
520
521 /* Also setup NX memory mapping */
522 mem_types[MT_MEMORY_RW].prot_sect |= PMD_SECT_XN;
523 mem_types[MT_MEMORY_RO].prot_sect |= PMD_SECT_XN;
524 }
525 if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
526 /*
527 * For ARMv7 with TEX remapping,
528 * - shared device is SXCB=1100
529 * - nonshared device is SXCB=0100
530 * - write combine device mem is SXCB=0001
531 * (Uncached Normal memory)
532 */
533 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_TEX(1);
534 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(1);
535 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_BUFFERABLE;
536 } else if (cpu_is_xsc3()) {
537 /*
538 * For Xscale3,
539 * - shared device is TEXCB=00101
540 * - nonshared device is TEXCB=01000
541 * - write combine device mem is TEXCB=00100
542 * (Inner/Outer Uncacheable in xsc3 parlance)
543 */
544 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_TEX(1) | PMD_SECT_BUFFERED;
545 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(2);
546 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1);
547 } else {
548 /*
549 * For ARMv6 and ARMv7 without TEX remapping,
550 * - shared device is TEXCB=00001
551 * - nonshared device is TEXCB=01000
552 * - write combine device mem is TEXCB=00100
553 * (Uncached Normal in ARMv6 parlance).
554 */
555 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_BUFFERED;
556 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(2);
557 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1);
558 }
559 } else {
560 /*
561 * On others, write combining is "Uncached/Buffered"
562 */
563 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_BUFFERABLE;
564 }
565
566 /*
567 * Now deal with the memory-type mappings
568 */
569 cp = &cache_policies[cachepolicy];
570 vecs_pgprot = kern_pgprot = user_pgprot = cp->pte;
571
572#ifndef CONFIG_ARM_LPAE
573 /*
574 * We don't use domains on ARMv6 (since this causes problems with
575 * v6/v7 kernels), so we must use a separate memory type for user
576 * r/o, kernel r/w to map the vectors page.
577 */
578 if (cpu_arch == CPU_ARCH_ARMv6)
579 vecs_pgprot |= L_PTE_MT_VECTORS;
580
581 /*
582 * Check is it with support for the PXN bit
583 * in the Short-descriptor translation table format descriptors.
584 */
585 if (cpu_arch == CPU_ARCH_ARMv7 &&
586 (read_cpuid_ext(CPUID_EXT_MMFR0) & 0xF) >= 4) {
587 user_pmd_table |= PMD_PXNTABLE;
588 }
589#endif
590
591 /*
592 * ARMv6 and above have extended page tables.
593 */
594 if (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP)) {
595#ifndef CONFIG_ARM_LPAE
596 /*
597 * Mark cache clean areas and XIP ROM read only
598 * from SVC mode and no access from userspace.
599 */
600 mem_types[MT_ROM].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
601 mem_types[MT_MINICLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
602 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
603 mem_types[MT_MEMORY_RO].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
604#endif
605
606 /*
607 * If the initial page tables were created with the S bit
608 * set, then we need to do the same here for the same
609 * reasons given in early_cachepolicy().
610 */
611 if (initial_pmd_value & PMD_SECT_S) {
612 user_pgprot |= L_PTE_SHARED;
613 kern_pgprot |= L_PTE_SHARED;
614 vecs_pgprot |= L_PTE_SHARED;
615 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_S;
616 mem_types[MT_DEVICE_WC].prot_pte |= L_PTE_SHARED;
617 mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_S;
618 mem_types[MT_DEVICE_CACHED].prot_pte |= L_PTE_SHARED;
619 mem_types[MT_MEMORY_RWX].prot_sect |= PMD_SECT_S;
620 mem_types[MT_MEMORY_RWX].prot_pte |= L_PTE_SHARED;
621 mem_types[MT_MEMORY_RW].prot_sect |= PMD_SECT_S;
622 mem_types[MT_MEMORY_RW].prot_pte |= L_PTE_SHARED;
623 mem_types[MT_MEMORY_RO].prot_sect |= PMD_SECT_S;
624 mem_types[MT_MEMORY_RO].prot_pte |= L_PTE_SHARED;
625 mem_types[MT_MEMORY_DMA_READY].prot_pte |= L_PTE_SHARED;
626 mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |= PMD_SECT_S;
627 mem_types[MT_MEMORY_RWX_NONCACHED].prot_pte |= L_PTE_SHARED;
628 }
629 }
630
631 /*
632 * Non-cacheable Normal - intended for memory areas that must
633 * not cause dirty cache line writebacks when used
634 */
635 if (cpu_arch >= CPU_ARCH_ARMv6) {
636 if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
637 /* Non-cacheable Normal is XCB = 001 */
638 mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |=
639 PMD_SECT_BUFFERED;
640 } else {
641 /* For both ARMv6 and non-TEX-remapping ARMv7 */
642 mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |=
643 PMD_SECT_TEX(1);
644 }
645 } else {
646 mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |= PMD_SECT_BUFFERABLE;
647 }
648
649#ifdef CONFIG_ARM_LPAE
650 /*
651 * Do not generate access flag faults for the kernel mappings.
652 */
653 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
654 mem_types[i].prot_pte |= PTE_EXT_AF;
655 if (mem_types[i].prot_sect)
656 mem_types[i].prot_sect |= PMD_SECT_AF;
657 }
658 kern_pgprot |= PTE_EXT_AF;
659 vecs_pgprot |= PTE_EXT_AF;
660
661 /*
662 * Set PXN for user mappings
663 */
664 user_pgprot |= PTE_EXT_PXN;
665#endif
666
667 for (i = 0; i < 16; i++) {
668 pteval_t v = pgprot_val(protection_map[i]);
669 protection_map[i] = __pgprot(v | user_pgprot);
670 }
671
672 mem_types[MT_LOW_VECTORS].prot_pte |= vecs_pgprot;
673 mem_types[MT_HIGH_VECTORS].prot_pte |= vecs_pgprot;
674
675 pgprot_user = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | user_pgprot);
676 pgprot_kernel = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG |
677 L_PTE_DIRTY | kern_pgprot);
678
679 mem_types[MT_LOW_VECTORS].prot_l1 |= ecc_mask;
680 mem_types[MT_HIGH_VECTORS].prot_l1 |= ecc_mask;
681 mem_types[MT_MEMORY_RWX].prot_sect |= ecc_mask | cp->pmd;
682 mem_types[MT_MEMORY_RWX].prot_pte |= kern_pgprot;
683 mem_types[MT_MEMORY_RW].prot_sect |= ecc_mask | cp->pmd;
684 mem_types[MT_MEMORY_RW].prot_pte |= kern_pgprot;
685 mem_types[MT_MEMORY_RO].prot_sect |= ecc_mask | cp->pmd;
686 mem_types[MT_MEMORY_RO].prot_pte |= kern_pgprot;
687 mem_types[MT_MEMORY_DMA_READY].prot_pte |= kern_pgprot;
688 mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |= ecc_mask;
689 mem_types[MT_ROM].prot_sect |= cp->pmd;
690
691 switch (cp->pmd) {
692 case PMD_SECT_WT:
693 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WT;
694 break;
695 case PMD_SECT_WB:
696 case PMD_SECT_WBWA:
697 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WB;
698 break;
699 }
700 pr_info("Memory policy: %sData cache %s\n",
701 ecc_mask ? "ECC enabled, " : "", cp->policy);
702
703 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
704 struct mem_type *t = &mem_types[i];
705 if (t->prot_l1)
706 t->prot_l1 |= PMD_DOMAIN(t->domain);
707 if (t->prot_sect)
708 t->prot_sect |= PMD_DOMAIN(t->domain);
709 }
710}
711
712#ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
713pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
714 unsigned long size, pgprot_t vma_prot)
715{
716 if (!pfn_valid(pfn))
717 return pgprot_noncached(vma_prot);
718 else if (file->f_flags & O_SYNC)
719 return pgprot_writecombine(vma_prot);
720 return vma_prot;
721}
722EXPORT_SYMBOL(phys_mem_access_prot);
723#endif
724
725#define vectors_base() (vectors_high() ? 0xffff0000 : 0)
726
727static void __init *early_alloc(unsigned long sz)
728{
729 void *ptr = memblock_alloc(sz, sz);
730
731 if (!ptr)
732 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
733 __func__, sz, sz);
734
735 return ptr;
736}
737
738static void *__init late_alloc(unsigned long sz)
739{
740 void *ptdesc = pagetable_alloc(GFP_PGTABLE_KERNEL & ~__GFP_HIGHMEM,
741 get_order(sz));
742
743 if (!ptdesc || !pagetable_pte_ctor(ptdesc))
744 BUG();
745 return ptdesc_to_virt(ptdesc);
746}
747
748static pte_t * __init arm_pte_alloc(pmd_t *pmd, unsigned long addr,
749 unsigned long prot,
750 void *(*alloc)(unsigned long sz))
751{
752 if (pmd_none(*pmd)) {
753 pte_t *pte = alloc(PTE_HWTABLE_OFF + PTE_HWTABLE_SIZE);
754 __pmd_populate(pmd, __pa(pte), prot);
755 }
756 BUG_ON(pmd_bad(*pmd));
757 return pte_offset_kernel(pmd, addr);
758}
759
760static pte_t * __init early_pte_alloc(pmd_t *pmd, unsigned long addr,
761 unsigned long prot)
762{
763 return arm_pte_alloc(pmd, addr, prot, early_alloc);
764}
765
766static void __init alloc_init_pte(pmd_t *pmd, unsigned long addr,
767 unsigned long end, unsigned long pfn,
768 const struct mem_type *type,
769 void *(*alloc)(unsigned long sz),
770 bool ng)
771{
772 pte_t *pte = arm_pte_alloc(pmd, addr, type->prot_l1, alloc);
773 do {
774 set_pte_ext(pte, pfn_pte(pfn, __pgprot(type->prot_pte)),
775 ng ? PTE_EXT_NG : 0);
776 pfn++;
777 } while (pte++, addr += PAGE_SIZE, addr != end);
778}
779
780static void __init __map_init_section(pmd_t *pmd, unsigned long addr,
781 unsigned long end, phys_addr_t phys,
782 const struct mem_type *type, bool ng)
783{
784 pmd_t *p = pmd;
785
786#ifndef CONFIG_ARM_LPAE
787 /*
788 * In classic MMU format, puds and pmds are folded in to
789 * the pgds. pmd_offset gives the PGD entry. PGDs refer to a
790 * group of L1 entries making up one logical pointer to
791 * an L2 table (2MB), where as PMDs refer to the individual
792 * L1 entries (1MB). Hence increment to get the correct
793 * offset for odd 1MB sections.
794 * (See arch/arm/include/asm/pgtable-2level.h)
795 */
796 if (addr & SECTION_SIZE)
797 pmd++;
798#endif
799 do {
800 *pmd = __pmd(phys | type->prot_sect | (ng ? PMD_SECT_nG : 0));
801 phys += SECTION_SIZE;
802 } while (pmd++, addr += SECTION_SIZE, addr != end);
803
804 flush_pmd_entry(p);
805}
806
807static void __init alloc_init_pmd(pud_t *pud, unsigned long addr,
808 unsigned long end, phys_addr_t phys,
809 const struct mem_type *type,
810 void *(*alloc)(unsigned long sz), bool ng)
811{
812 pmd_t *pmd = pmd_offset(pud, addr);
813 unsigned long next;
814
815 do {
816 /*
817 * With LPAE, we must loop over to map
818 * all the pmds for the given range.
819 */
820 next = pmd_addr_end(addr, end);
821
822 /*
823 * Try a section mapping - addr, next and phys must all be
824 * aligned to a section boundary.
825 */
826 if (type->prot_sect &&
827 ((addr | next | phys) & ~SECTION_MASK) == 0) {
828 __map_init_section(pmd, addr, next, phys, type, ng);
829 } else {
830 alloc_init_pte(pmd, addr, next,
831 __phys_to_pfn(phys), type, alloc, ng);
832 }
833
834 phys += next - addr;
835
836 } while (pmd++, addr = next, addr != end);
837}
838
839static void __init alloc_init_pud(p4d_t *p4d, unsigned long addr,
840 unsigned long end, phys_addr_t phys,
841 const struct mem_type *type,
842 void *(*alloc)(unsigned long sz), bool ng)
843{
844 pud_t *pud = pud_offset(p4d, addr);
845 unsigned long next;
846
847 do {
848 next = pud_addr_end(addr, end);
849 alloc_init_pmd(pud, addr, next, phys, type, alloc, ng);
850 phys += next - addr;
851 } while (pud++, addr = next, addr != end);
852}
853
854static void __init alloc_init_p4d(pgd_t *pgd, unsigned long addr,
855 unsigned long end, phys_addr_t phys,
856 const struct mem_type *type,
857 void *(*alloc)(unsigned long sz), bool ng)
858{
859 p4d_t *p4d = p4d_offset(pgd, addr);
860 unsigned long next;
861
862 do {
863 next = p4d_addr_end(addr, end);
864 alloc_init_pud(p4d, addr, next, phys, type, alloc, ng);
865 phys += next - addr;
866 } while (p4d++, addr = next, addr != end);
867}
868
869#ifndef CONFIG_ARM_LPAE
870static void __init create_36bit_mapping(struct mm_struct *mm,
871 struct map_desc *md,
872 const struct mem_type *type,
873 bool ng)
874{
875 unsigned long addr, length, end;
876 phys_addr_t phys;
877 pgd_t *pgd;
878
879 addr = md->virtual;
880 phys = __pfn_to_phys(md->pfn);
881 length = PAGE_ALIGN(md->length);
882
883 if (!(cpu_architecture() >= CPU_ARCH_ARMv6 || cpu_is_xsc3())) {
884 pr_err("MM: CPU does not support supersection mapping for 0x%08llx at 0x%08lx\n",
885 (long long)__pfn_to_phys((u64)md->pfn), addr);
886 return;
887 }
888
889 /* N.B. ARMv6 supersections are only defined to work with domain 0.
890 * Since domain assignments can in fact be arbitrary, the
891 * 'domain == 0' check below is required to insure that ARMv6
892 * supersections are only allocated for domain 0 regardless
893 * of the actual domain assignments in use.
894 */
895 if (type->domain) {
896 pr_err("MM: invalid domain in supersection mapping for 0x%08llx at 0x%08lx\n",
897 (long long)__pfn_to_phys((u64)md->pfn), addr);
898 return;
899 }
900
901 if ((addr | length | __pfn_to_phys(md->pfn)) & ~SUPERSECTION_MASK) {
902 pr_err("MM: cannot create mapping for 0x%08llx at 0x%08lx invalid alignment\n",
903 (long long)__pfn_to_phys((u64)md->pfn), addr);
904 return;
905 }
906
907 /*
908 * Shift bits [35:32] of address into bits [23:20] of PMD
909 * (See ARMv6 spec).
910 */
911 phys |= (((md->pfn >> (32 - PAGE_SHIFT)) & 0xF) << 20);
912
913 pgd = pgd_offset(mm, addr);
914 end = addr + length;
915 do {
916 p4d_t *p4d = p4d_offset(pgd, addr);
917 pud_t *pud = pud_offset(p4d, addr);
918 pmd_t *pmd = pmd_offset(pud, addr);
919 int i;
920
921 for (i = 0; i < 16; i++)
922 *pmd++ = __pmd(phys | type->prot_sect | PMD_SECT_SUPER |
923 (ng ? PMD_SECT_nG : 0));
924
925 addr += SUPERSECTION_SIZE;
926 phys += SUPERSECTION_SIZE;
927 pgd += SUPERSECTION_SIZE >> PGDIR_SHIFT;
928 } while (addr != end);
929}
930#endif /* !CONFIG_ARM_LPAE */
931
932static void __init __create_mapping(struct mm_struct *mm, struct map_desc *md,
933 void *(*alloc)(unsigned long sz),
934 bool ng)
935{
936 unsigned long addr, length, end;
937 phys_addr_t phys;
938 const struct mem_type *type;
939 pgd_t *pgd;
940
941 type = &mem_types[md->type];
942
943#ifndef CONFIG_ARM_LPAE
944 /*
945 * Catch 36-bit addresses
946 */
947 if (md->pfn >= 0x100000) {
948 create_36bit_mapping(mm, md, type, ng);
949 return;
950 }
951#endif
952
953 addr = md->virtual & PAGE_MASK;
954 phys = __pfn_to_phys(md->pfn);
955 length = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK));
956
957 if (type->prot_l1 == 0 && ((addr | phys | length) & ~SECTION_MASK)) {
958 pr_warn("BUG: map for 0x%08llx at 0x%08lx can not be mapped using pages, ignoring.\n",
959 (long long)__pfn_to_phys(md->pfn), addr);
960 return;
961 }
962
963 pgd = pgd_offset(mm, addr);
964 end = addr + length;
965 do {
966 unsigned long next = pgd_addr_end(addr, end);
967
968 alloc_init_p4d(pgd, addr, next, phys, type, alloc, ng);
969
970 phys += next - addr;
971 addr = next;
972 } while (pgd++, addr != end);
973}
974
975/*
976 * Create the page directory entries and any necessary
977 * page tables for the mapping specified by `md'. We
978 * are able to cope here with varying sizes and address
979 * offsets, and we take full advantage of sections and
980 * supersections.
981 */
982static void __init create_mapping(struct map_desc *md)
983{
984 if (md->virtual != vectors_base() && md->virtual < TASK_SIZE) {
985 pr_warn("BUG: not creating mapping for 0x%08llx at 0x%08lx in user region\n",
986 (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
987 return;
988 }
989
990 if (md->type == MT_DEVICE &&
991 md->virtual >= PAGE_OFFSET && md->virtual < FIXADDR_START &&
992 (md->virtual < VMALLOC_START || md->virtual >= VMALLOC_END)) {
993 pr_warn("BUG: mapping for 0x%08llx at 0x%08lx out of vmalloc space\n",
994 (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
995 }
996
997 __create_mapping(&init_mm, md, early_alloc, false);
998}
999
1000void __init create_mapping_late(struct mm_struct *mm, struct map_desc *md,
1001 bool ng)
1002{
1003#ifdef CONFIG_ARM_LPAE
1004 p4d_t *p4d;
1005 pud_t *pud;
1006
1007 p4d = p4d_alloc(mm, pgd_offset(mm, md->virtual), md->virtual);
1008 if (WARN_ON(!p4d))
1009 return;
1010 pud = pud_alloc(mm, p4d, md->virtual);
1011 if (WARN_ON(!pud))
1012 return;
1013 pmd_alloc(mm, pud, 0);
1014#endif
1015 __create_mapping(mm, md, late_alloc, ng);
1016}
1017
1018/*
1019 * Create the architecture specific mappings
1020 */
1021void __init iotable_init(struct map_desc *io_desc, int nr)
1022{
1023 struct map_desc *md;
1024 struct vm_struct *vm;
1025 struct static_vm *svm;
1026
1027 if (!nr)
1028 return;
1029
1030 svm = memblock_alloc(sizeof(*svm) * nr, __alignof__(*svm));
1031 if (!svm)
1032 panic("%s: Failed to allocate %zu bytes align=0x%zx\n",
1033 __func__, sizeof(*svm) * nr, __alignof__(*svm));
1034
1035 for (md = io_desc; nr; md++, nr--) {
1036 create_mapping(md);
1037
1038 vm = &svm->vm;
1039 vm->addr = (void *)(md->virtual & PAGE_MASK);
1040 vm->size = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK));
1041 vm->phys_addr = __pfn_to_phys(md->pfn);
1042 vm->flags = VM_IOREMAP | VM_ARM_STATIC_MAPPING;
1043 vm->flags |= VM_ARM_MTYPE(md->type);
1044 vm->caller = iotable_init;
1045 add_static_vm_early(svm++);
1046 }
1047}
1048
1049void __init vm_reserve_area_early(unsigned long addr, unsigned long size,
1050 void *caller)
1051{
1052 struct vm_struct *vm;
1053 struct static_vm *svm;
1054
1055 svm = memblock_alloc(sizeof(*svm), __alignof__(*svm));
1056 if (!svm)
1057 panic("%s: Failed to allocate %zu bytes align=0x%zx\n",
1058 __func__, sizeof(*svm), __alignof__(*svm));
1059
1060 vm = &svm->vm;
1061 vm->addr = (void *)addr;
1062 vm->size = size;
1063 vm->flags = VM_IOREMAP | VM_ARM_EMPTY_MAPPING;
1064 vm->caller = caller;
1065 add_static_vm_early(svm);
1066}
1067
1068#ifndef CONFIG_ARM_LPAE
1069
1070/*
1071 * The Linux PMD is made of two consecutive section entries covering 2MB
1072 * (see definition in include/asm/pgtable-2level.h). However a call to
1073 * create_mapping() may optimize static mappings by using individual
1074 * 1MB section mappings. This leaves the actual PMD potentially half
1075 * initialized if the top or bottom section entry isn't used, leaving it
1076 * open to problems if a subsequent ioremap() or vmalloc() tries to use
1077 * the virtual space left free by that unused section entry.
1078 *
1079 * Let's avoid the issue by inserting dummy vm entries covering the unused
1080 * PMD halves once the static mappings are in place.
1081 */
1082
1083static void __init pmd_empty_section_gap(unsigned long addr)
1084{
1085 vm_reserve_area_early(addr, SECTION_SIZE, pmd_empty_section_gap);
1086}
1087
1088static void __init fill_pmd_gaps(void)
1089{
1090 struct static_vm *svm;
1091 struct vm_struct *vm;
1092 unsigned long addr, next = 0;
1093 pmd_t *pmd;
1094
1095 list_for_each_entry(svm, &static_vmlist, list) {
1096 vm = &svm->vm;
1097 addr = (unsigned long)vm->addr;
1098 if (addr < next)
1099 continue;
1100
1101 /*
1102 * Check if this vm starts on an odd section boundary.
1103 * If so and the first section entry for this PMD is free
1104 * then we block the corresponding virtual address.
1105 */
1106 if ((addr & ~PMD_MASK) == SECTION_SIZE) {
1107 pmd = pmd_off_k(addr);
1108 if (pmd_none(*pmd))
1109 pmd_empty_section_gap(addr & PMD_MASK);
1110 }
1111
1112 /*
1113 * Then check if this vm ends on an odd section boundary.
1114 * If so and the second section entry for this PMD is empty
1115 * then we block the corresponding virtual address.
1116 */
1117 addr += vm->size;
1118 if ((addr & ~PMD_MASK) == SECTION_SIZE) {
1119 pmd = pmd_off_k(addr) + 1;
1120 if (pmd_none(*pmd))
1121 pmd_empty_section_gap(addr);
1122 }
1123
1124 /* no need to look at any vm entry until we hit the next PMD */
1125 next = (addr + PMD_SIZE - 1) & PMD_MASK;
1126 }
1127}
1128
1129#else
1130#define fill_pmd_gaps() do { } while (0)
1131#endif
1132
1133#if defined(CONFIG_PCI) && !defined(CONFIG_NEED_MACH_IO_H)
1134static void __init pci_reserve_io(void)
1135{
1136 struct static_vm *svm;
1137
1138 svm = find_static_vm_vaddr((void *)PCI_IO_VIRT_BASE);
1139 if (svm)
1140 return;
1141
1142 vm_reserve_area_early(PCI_IO_VIRT_BASE, SZ_2M, pci_reserve_io);
1143}
1144#else
1145#define pci_reserve_io() do { } while (0)
1146#endif
1147
1148#ifdef CONFIG_DEBUG_LL
1149void __init debug_ll_io_init(void)
1150{
1151 struct map_desc map;
1152
1153 debug_ll_addr(&map.pfn, &map.virtual);
1154 if (!map.pfn || !map.virtual)
1155 return;
1156 map.pfn = __phys_to_pfn(map.pfn);
1157 map.virtual &= PAGE_MASK;
1158 map.length = PAGE_SIZE;
1159 map.type = MT_DEVICE;
1160 iotable_init(&map, 1);
1161}
1162#endif
1163
1164static unsigned long __initdata vmalloc_size = 240 * SZ_1M;
1165
1166/*
1167 * vmalloc=size forces the vmalloc area to be exactly 'size'
1168 * bytes. This can be used to increase (or decrease) the vmalloc
1169 * area - the default is 240MiB.
1170 */
1171static int __init early_vmalloc(char *arg)
1172{
1173 unsigned long vmalloc_reserve = memparse(arg, NULL);
1174 unsigned long vmalloc_max;
1175
1176 if (vmalloc_reserve < SZ_16M) {
1177 vmalloc_reserve = SZ_16M;
1178 pr_warn("vmalloc area is too small, limiting to %luMiB\n",
1179 vmalloc_reserve >> 20);
1180 }
1181
1182 vmalloc_max = VMALLOC_END - (PAGE_OFFSET + SZ_32M + VMALLOC_OFFSET);
1183 if (vmalloc_reserve > vmalloc_max) {
1184 vmalloc_reserve = vmalloc_max;
1185 pr_warn("vmalloc area is too big, limiting to %luMiB\n",
1186 vmalloc_reserve >> 20);
1187 }
1188
1189 vmalloc_size = vmalloc_reserve;
1190 return 0;
1191}
1192early_param("vmalloc", early_vmalloc);
1193
1194phys_addr_t arm_lowmem_limit __initdata = 0;
1195
1196void __init adjust_lowmem_bounds(void)
1197{
1198 phys_addr_t block_start, block_end, memblock_limit = 0;
1199 u64 vmalloc_limit, i;
1200 phys_addr_t lowmem_limit = 0;
1201
1202 /*
1203 * Let's use our own (unoptimized) equivalent of __pa() that is
1204 * not affected by wrap-arounds when sizeof(phys_addr_t) == 4.
1205 * The result is used as the upper bound on physical memory address
1206 * and may itself be outside the valid range for which phys_addr_t
1207 * and therefore __pa() is defined.
1208 */
1209 vmalloc_limit = (u64)VMALLOC_END - vmalloc_size - VMALLOC_OFFSET -
1210 PAGE_OFFSET + PHYS_OFFSET;
1211
1212 /*
1213 * The first usable region must be PMD aligned. Mark its start
1214 * as MEMBLOCK_NOMAP if it isn't
1215 */
1216 for_each_mem_range(i, &block_start, &block_end) {
1217 if (!IS_ALIGNED(block_start, PMD_SIZE)) {
1218 phys_addr_t len;
1219
1220 len = round_up(block_start, PMD_SIZE) - block_start;
1221 memblock_mark_nomap(block_start, len);
1222 }
1223 break;
1224 }
1225
1226 for_each_mem_range(i, &block_start, &block_end) {
1227 if (block_start < vmalloc_limit) {
1228 if (block_end > lowmem_limit)
1229 /*
1230 * Compare as u64 to ensure vmalloc_limit does
1231 * not get truncated. block_end should always
1232 * fit in phys_addr_t so there should be no
1233 * issue with assignment.
1234 */
1235 lowmem_limit = min_t(u64,
1236 vmalloc_limit,
1237 block_end);
1238
1239 /*
1240 * Find the first non-pmd-aligned page, and point
1241 * memblock_limit at it. This relies on rounding the
1242 * limit down to be pmd-aligned, which happens at the
1243 * end of this function.
1244 *
1245 * With this algorithm, the start or end of almost any
1246 * bank can be non-pmd-aligned. The only exception is
1247 * that the start of the bank 0 must be section-
1248 * aligned, since otherwise memory would need to be
1249 * allocated when mapping the start of bank 0, which
1250 * occurs before any free memory is mapped.
1251 */
1252 if (!memblock_limit) {
1253 if (!IS_ALIGNED(block_start, PMD_SIZE))
1254 memblock_limit = block_start;
1255 else if (!IS_ALIGNED(block_end, PMD_SIZE))
1256 memblock_limit = lowmem_limit;
1257 }
1258
1259 }
1260 }
1261
1262 arm_lowmem_limit = lowmem_limit;
1263
1264 high_memory = __va(arm_lowmem_limit - 1) + 1;
1265
1266 if (!memblock_limit)
1267 memblock_limit = arm_lowmem_limit;
1268
1269 /*
1270 * Round the memblock limit down to a pmd size. This
1271 * helps to ensure that we will allocate memory from the
1272 * last full pmd, which should be mapped.
1273 */
1274 memblock_limit = round_down(memblock_limit, PMD_SIZE);
1275
1276 if (!IS_ENABLED(CONFIG_HIGHMEM) || cache_is_vipt_aliasing()) {
1277 if (memblock_end_of_DRAM() > arm_lowmem_limit) {
1278 phys_addr_t end = memblock_end_of_DRAM();
1279
1280 pr_notice("Ignoring RAM at %pa-%pa\n",
1281 &memblock_limit, &end);
1282 pr_notice("Consider using a HIGHMEM enabled kernel.\n");
1283
1284 memblock_remove(memblock_limit, end - memblock_limit);
1285 }
1286 }
1287
1288 memblock_set_current_limit(memblock_limit);
1289}
1290
1291static __init void prepare_page_table(void)
1292{
1293 unsigned long addr;
1294 phys_addr_t end;
1295
1296 /*
1297 * Clear out all the mappings below the kernel image.
1298 */
1299#ifdef CONFIG_KASAN
1300 /*
1301 * KASan's shadow memory inserts itself between the TASK_SIZE
1302 * and MODULES_VADDR. Do not clear the KASan shadow memory mappings.
1303 */
1304 for (addr = 0; addr < KASAN_SHADOW_START; addr += PMD_SIZE)
1305 pmd_clear(pmd_off_k(addr));
1306 /*
1307 * Skip over the KASan shadow area. KASAN_SHADOW_END is sometimes
1308 * equal to MODULES_VADDR and then we exit the pmd clearing. If we
1309 * are using a thumb-compiled kernel, there there will be 8MB more
1310 * to clear as KASan always offset to 16 MB below MODULES_VADDR.
1311 */
1312 for (addr = KASAN_SHADOW_END; addr < MODULES_VADDR; addr += PMD_SIZE)
1313 pmd_clear(pmd_off_k(addr));
1314#else
1315 for (addr = 0; addr < MODULES_VADDR; addr += PMD_SIZE)
1316 pmd_clear(pmd_off_k(addr));
1317#endif
1318
1319#ifdef CONFIG_XIP_KERNEL
1320 /* The XIP kernel is mapped in the module area -- skip over it */
1321 addr = ((unsigned long)_exiprom + PMD_SIZE - 1) & PMD_MASK;
1322#endif
1323 for ( ; addr < PAGE_OFFSET; addr += PMD_SIZE)
1324 pmd_clear(pmd_off_k(addr));
1325
1326 /*
1327 * Find the end of the first block of lowmem.
1328 */
1329 end = memblock.memory.regions[0].base + memblock.memory.regions[0].size;
1330 if (end >= arm_lowmem_limit)
1331 end = arm_lowmem_limit;
1332
1333 /*
1334 * Clear out all the kernel space mappings, except for the first
1335 * memory bank, up to the vmalloc region.
1336 */
1337 for (addr = __phys_to_virt(end);
1338 addr < VMALLOC_START; addr += PMD_SIZE)
1339 pmd_clear(pmd_off_k(addr));
1340}
1341
1342#ifdef CONFIG_ARM_LPAE
1343/* the first page is reserved for pgd */
1344#define SWAPPER_PG_DIR_SIZE (PAGE_SIZE + \
1345 PTRS_PER_PGD * PTRS_PER_PMD * sizeof(pmd_t))
1346#else
1347#define SWAPPER_PG_DIR_SIZE (PTRS_PER_PGD * sizeof(pgd_t))
1348#endif
1349
1350/*
1351 * Reserve the special regions of memory
1352 */
1353void __init arm_mm_memblock_reserve(void)
1354{
1355 /*
1356 * Reserve the page tables. These are already in use,
1357 * and can only be in node 0.
1358 */
1359 memblock_reserve(__pa(swapper_pg_dir), SWAPPER_PG_DIR_SIZE);
1360
1361#ifdef CONFIG_SA1111
1362 /*
1363 * Because of the SA1111 DMA bug, we want to preserve our
1364 * precious DMA-able memory...
1365 */
1366 memblock_reserve(PHYS_OFFSET, __pa(swapper_pg_dir) - PHYS_OFFSET);
1367#endif
1368}
1369
1370/*
1371 * Set up the device mappings. Since we clear out the page tables for all
1372 * mappings above VMALLOC_START, except early fixmap, we might remove debug
1373 * device mappings. This means earlycon can be used to debug this function
1374 * Any other function or debugging method which may touch any device _will_
1375 * crash the kernel.
1376 */
1377static void __init devicemaps_init(const struct machine_desc *mdesc)
1378{
1379 struct map_desc map;
1380 unsigned long addr;
1381 void *vectors;
1382
1383 /*
1384 * Allocate the vector page early.
1385 */
1386 vectors = early_alloc(PAGE_SIZE * 2);
1387
1388 early_trap_init(vectors);
1389
1390 /*
1391 * Clear page table except top pmd used by early fixmaps
1392 */
1393 for (addr = VMALLOC_START; addr < (FIXADDR_TOP & PMD_MASK); addr += PMD_SIZE)
1394 pmd_clear(pmd_off_k(addr));
1395
1396 if (__atags_pointer) {
1397 /* create a read-only mapping of the device tree */
1398 map.pfn = __phys_to_pfn(__atags_pointer & SECTION_MASK);
1399 map.virtual = FDT_FIXED_BASE;
1400 map.length = FDT_FIXED_SIZE;
1401 map.type = MT_MEMORY_RO;
1402 create_mapping(&map);
1403 }
1404
1405 /*
1406 * Map the kernel if it is XIP.
1407 * It is always first in the modulearea.
1408 */
1409#ifdef CONFIG_XIP_KERNEL
1410 map.pfn = __phys_to_pfn(CONFIG_XIP_PHYS_ADDR & SECTION_MASK);
1411 map.virtual = MODULES_VADDR;
1412 map.length = ((unsigned long)_exiprom - map.virtual + ~SECTION_MASK) & SECTION_MASK;
1413 map.type = MT_ROM;
1414 create_mapping(&map);
1415#endif
1416
1417 /*
1418 * Map the cache flushing regions.
1419 */
1420#ifdef FLUSH_BASE
1421 map.pfn = __phys_to_pfn(FLUSH_BASE_PHYS);
1422 map.virtual = FLUSH_BASE;
1423 map.length = SZ_1M;
1424 map.type = MT_CACHECLEAN;
1425 create_mapping(&map);
1426#endif
1427#ifdef FLUSH_BASE_MINICACHE
1428 map.pfn = __phys_to_pfn(FLUSH_BASE_PHYS + SZ_1M);
1429 map.virtual = FLUSH_BASE_MINICACHE;
1430 map.length = SZ_1M;
1431 map.type = MT_MINICLEAN;
1432 create_mapping(&map);
1433#endif
1434
1435 /*
1436 * Create a mapping for the machine vectors at the high-vectors
1437 * location (0xffff0000). If we aren't using high-vectors, also
1438 * create a mapping at the low-vectors virtual address.
1439 */
1440 map.pfn = __phys_to_pfn(virt_to_phys(vectors));
1441 map.virtual = 0xffff0000;
1442 map.length = PAGE_SIZE;
1443#ifdef CONFIG_KUSER_HELPERS
1444 map.type = MT_HIGH_VECTORS;
1445#else
1446 map.type = MT_LOW_VECTORS;
1447#endif
1448 create_mapping(&map);
1449
1450 if (!vectors_high()) {
1451 map.virtual = 0;
1452 map.length = PAGE_SIZE * 2;
1453 map.type = MT_LOW_VECTORS;
1454 create_mapping(&map);
1455 }
1456
1457 /* Now create a kernel read-only mapping */
1458 map.pfn += 1;
1459 map.virtual = 0xffff0000 + PAGE_SIZE;
1460 map.length = PAGE_SIZE;
1461 map.type = MT_LOW_VECTORS;
1462 create_mapping(&map);
1463
1464 /*
1465 * Ask the machine support to map in the statically mapped devices.
1466 */
1467 if (mdesc->map_io)
1468 mdesc->map_io();
1469 else
1470 debug_ll_io_init();
1471 fill_pmd_gaps();
1472
1473 /* Reserve fixed i/o space in VMALLOC region */
1474 pci_reserve_io();
1475
1476 /*
1477 * Finally flush the caches and tlb to ensure that we're in a
1478 * consistent state wrt the writebuffer. This also ensures that
1479 * any write-allocated cache lines in the vector page are written
1480 * back. After this point, we can start to touch devices again.
1481 */
1482 local_flush_tlb_all();
1483 flush_cache_all();
1484
1485 /* Enable asynchronous aborts */
1486 early_abt_enable();
1487}
1488
1489static void __init kmap_init(void)
1490{
1491#ifdef CONFIG_HIGHMEM
1492 pkmap_page_table = early_pte_alloc(pmd_off_k(PKMAP_BASE),
1493 PKMAP_BASE, _PAGE_KERNEL_TABLE);
1494#endif
1495
1496 early_pte_alloc(pmd_off_k(FIXADDR_START), FIXADDR_START,
1497 _PAGE_KERNEL_TABLE);
1498}
1499
1500static void __init map_lowmem(void)
1501{
1502 phys_addr_t start, end;
1503 u64 i;
1504
1505 /* Map all the lowmem memory banks. */
1506 for_each_mem_range(i, &start, &end) {
1507 struct map_desc map;
1508
1509 pr_debug("map lowmem start: 0x%08llx, end: 0x%08llx\n",
1510 (long long)start, (long long)end);
1511 if (end > arm_lowmem_limit)
1512 end = arm_lowmem_limit;
1513 if (start >= end)
1514 break;
1515
1516 /*
1517 * If our kernel image is in the VMALLOC area we need to remove
1518 * the kernel physical memory from lowmem since the kernel will
1519 * be mapped separately.
1520 *
1521 * The kernel will typically be at the very start of lowmem,
1522 * but any placement relative to memory ranges is possible.
1523 *
1524 * If the memblock contains the kernel, we have to chisel out
1525 * the kernel memory from it and map each part separately. We
1526 * get 6 different theoretical cases:
1527 *
1528 * +--------+ +--------+
1529 * +-- start --+ +--------+ | Kernel | | Kernel |
1530 * | | | Kernel | | case 2 | | case 5 |
1531 * | | | case 1 | +--------+ | | +--------+
1532 * | Memory | +--------+ | | | Kernel |
1533 * | range | +--------+ | | | case 6 |
1534 * | | | Kernel | +--------+ | | +--------+
1535 * | | | case 3 | | Kernel | | |
1536 * +-- end ----+ +--------+ | case 4 | | |
1537 * +--------+ +--------+
1538 */
1539
1540 /* Case 5: kernel covers range, don't map anything, should be rare */
1541 if ((start > kernel_sec_start) && (end < kernel_sec_end))
1542 break;
1543
1544 /* Cases where the kernel is starting inside the range */
1545 if ((kernel_sec_start >= start) && (kernel_sec_start <= end)) {
1546 /* Case 6: kernel is embedded in the range, we need two mappings */
1547 if ((start < kernel_sec_start) && (end > kernel_sec_end)) {
1548 /* Map memory below the kernel */
1549 map.pfn = __phys_to_pfn(start);
1550 map.virtual = __phys_to_virt(start);
1551 map.length = kernel_sec_start - start;
1552 map.type = MT_MEMORY_RW;
1553 create_mapping(&map);
1554 /* Map memory above the kernel */
1555 map.pfn = __phys_to_pfn(kernel_sec_end);
1556 map.virtual = __phys_to_virt(kernel_sec_end);
1557 map.length = end - kernel_sec_end;
1558 map.type = MT_MEMORY_RW;
1559 create_mapping(&map);
1560 break;
1561 }
1562 /* Case 1: kernel and range start at the same address, should be common */
1563 if (kernel_sec_start == start)
1564 start = kernel_sec_end;
1565 /* Case 3: kernel and range end at the same address, should be rare */
1566 if (kernel_sec_end == end)
1567 end = kernel_sec_start;
1568 } else if ((kernel_sec_start < start) && (kernel_sec_end > start) && (kernel_sec_end < end)) {
1569 /* Case 2: kernel ends inside range, starts below it */
1570 start = kernel_sec_end;
1571 } else if ((kernel_sec_start > start) && (kernel_sec_start < end) && (kernel_sec_end > end)) {
1572 /* Case 4: kernel starts inside range, ends above it */
1573 end = kernel_sec_start;
1574 }
1575 map.pfn = __phys_to_pfn(start);
1576 map.virtual = __phys_to_virt(start);
1577 map.length = end - start;
1578 map.type = MT_MEMORY_RW;
1579 create_mapping(&map);
1580 }
1581}
1582
1583static void __init map_kernel(void)
1584{
1585 /*
1586 * We use the well known kernel section start and end and split the area in the
1587 * middle like this:
1588 * . .
1589 * | RW memory |
1590 * +----------------+ kernel_x_start
1591 * | Executable |
1592 * | kernel memory |
1593 * +----------------+ kernel_x_end / kernel_nx_start
1594 * | Non-executable |
1595 * | kernel memory |
1596 * +----------------+ kernel_nx_end
1597 * | RW memory |
1598 * . .
1599 *
1600 * Notice that we are dealing with section sized mappings here so all of this
1601 * will be bumped to the closest section boundary. This means that some of the
1602 * non-executable part of the kernel memory is actually mapped as executable.
1603 * This will only persist until we turn on proper memory management later on
1604 * and we remap the whole kernel with page granularity.
1605 */
1606 phys_addr_t kernel_x_start = kernel_sec_start;
1607 phys_addr_t kernel_x_end = round_up(__pa(__init_end), SECTION_SIZE);
1608 phys_addr_t kernel_nx_start = kernel_x_end;
1609 phys_addr_t kernel_nx_end = kernel_sec_end;
1610 struct map_desc map;
1611
1612 map.pfn = __phys_to_pfn(kernel_x_start);
1613 map.virtual = __phys_to_virt(kernel_x_start);
1614 map.length = kernel_x_end - kernel_x_start;
1615 map.type = MT_MEMORY_RWX;
1616 create_mapping(&map);
1617
1618 /* If the nx part is small it may end up covered by the tail of the RWX section */
1619 if (kernel_x_end == kernel_nx_end)
1620 return;
1621
1622 map.pfn = __phys_to_pfn(kernel_nx_start);
1623 map.virtual = __phys_to_virt(kernel_nx_start);
1624 map.length = kernel_nx_end - kernel_nx_start;
1625 map.type = MT_MEMORY_RW;
1626 create_mapping(&map);
1627}
1628
1629#ifdef CONFIG_ARM_PV_FIXUP
1630typedef void pgtables_remap(long long offset, unsigned long pgd);
1631pgtables_remap lpae_pgtables_remap_asm;
1632
1633/*
1634 * early_paging_init() recreates boot time page table setup, allowing machines
1635 * to switch over to a high (>4G) address space on LPAE systems
1636 */
1637static void __init early_paging_init(const struct machine_desc *mdesc)
1638{
1639 pgtables_remap *lpae_pgtables_remap;
1640 unsigned long pa_pgd;
1641 unsigned int cr, ttbcr;
1642 long long offset;
1643
1644 if (!mdesc->pv_fixup)
1645 return;
1646
1647 offset = mdesc->pv_fixup();
1648 if (offset == 0)
1649 return;
1650
1651 /*
1652 * Offset the kernel section physical offsets so that the kernel
1653 * mapping will work out later on.
1654 */
1655 kernel_sec_start += offset;
1656 kernel_sec_end += offset;
1657
1658 /*
1659 * Get the address of the remap function in the 1:1 identity
1660 * mapping setup by the early page table assembly code. We
1661 * must get this prior to the pv update. The following barrier
1662 * ensures that this is complete before we fixup any P:V offsets.
1663 */
1664 lpae_pgtables_remap = (pgtables_remap *)(unsigned long)__pa(lpae_pgtables_remap_asm);
1665 pa_pgd = __pa(swapper_pg_dir);
1666 barrier();
1667
1668 pr_info("Switching physical address space to 0x%08llx\n",
1669 (u64)PHYS_OFFSET + offset);
1670
1671 /* Re-set the phys pfn offset, and the pv offset */
1672 __pv_offset += offset;
1673 __pv_phys_pfn_offset += PFN_DOWN(offset);
1674
1675 /* Run the patch stub to update the constants */
1676 fixup_pv_table(&__pv_table_begin,
1677 (&__pv_table_end - &__pv_table_begin) << 2);
1678
1679 /*
1680 * We changing not only the virtual to physical mapping, but also
1681 * the physical addresses used to access memory. We need to flush
1682 * all levels of cache in the system with caching disabled to
1683 * ensure that all data is written back, and nothing is prefetched
1684 * into the caches. We also need to prevent the TLB walkers
1685 * allocating into the caches too. Note that this is ARMv7 LPAE
1686 * specific.
1687 */
1688 cr = get_cr();
1689 set_cr(cr & ~(CR_I | CR_C));
1690 asm("mrc p15, 0, %0, c2, c0, 2" : "=r" (ttbcr));
1691 asm volatile("mcr p15, 0, %0, c2, c0, 2"
1692 : : "r" (ttbcr & ~(3 << 8 | 3 << 10)));
1693 flush_cache_all();
1694
1695 /*
1696 * Fixup the page tables - this must be in the idmap region as
1697 * we need to disable the MMU to do this safely, and hence it
1698 * needs to be assembly. It's fairly simple, as we're using the
1699 * temporary tables setup by the initial assembly code.
1700 */
1701 lpae_pgtables_remap(offset, pa_pgd);
1702
1703 /* Re-enable the caches and cacheable TLB walks */
1704 asm volatile("mcr p15, 0, %0, c2, c0, 2" : : "r" (ttbcr));
1705 set_cr(cr);
1706}
1707
1708#else
1709
1710static void __init early_paging_init(const struct machine_desc *mdesc)
1711{
1712 long long offset;
1713
1714 if (!mdesc->pv_fixup)
1715 return;
1716
1717 offset = mdesc->pv_fixup();
1718 if (offset == 0)
1719 return;
1720
1721 pr_crit("Physical address space modification is only to support Keystone2.\n");
1722 pr_crit("Please enable ARM_LPAE and ARM_PATCH_PHYS_VIRT support to use this\n");
1723 pr_crit("feature. Your kernel may crash now, have a good day.\n");
1724 add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
1725}
1726
1727#endif
1728
1729static void __init early_fixmap_shutdown(void)
1730{
1731 int i;
1732 unsigned long va = fix_to_virt(__end_of_permanent_fixed_addresses - 1);
1733
1734 pte_offset_fixmap = pte_offset_late_fixmap;
1735 pmd_clear(fixmap_pmd(va));
1736 local_flush_tlb_kernel_page(va);
1737
1738 for (i = 0; i < __end_of_permanent_fixed_addresses; i++) {
1739 pte_t *pte;
1740 struct map_desc map;
1741
1742 map.virtual = fix_to_virt(i);
1743 pte = pte_offset_early_fixmap(pmd_off_k(map.virtual), map.virtual);
1744
1745 /* Only i/o device mappings are supported ATM */
1746 if (pte_none(*pte) ||
1747 (pte_val(*pte) & L_PTE_MT_MASK) != L_PTE_MT_DEV_SHARED)
1748 continue;
1749
1750 map.pfn = pte_pfn(*pte);
1751 map.type = MT_DEVICE;
1752 map.length = PAGE_SIZE;
1753
1754 create_mapping(&map);
1755 }
1756}
1757
1758/*
1759 * paging_init() sets up the page tables, initialises the zone memory
1760 * maps, and sets up the zero page, bad page and bad page tables.
1761 */
1762void __init paging_init(const struct machine_desc *mdesc)
1763{
1764 void *zero_page;
1765
1766 pr_debug("physical kernel sections: 0x%08llx-0x%08llx\n",
1767 kernel_sec_start, kernel_sec_end);
1768
1769 prepare_page_table();
1770 map_lowmem();
1771 memblock_set_current_limit(arm_lowmem_limit);
1772 pr_debug("lowmem limit is %08llx\n", (long long)arm_lowmem_limit);
1773 /*
1774 * After this point early_alloc(), i.e. the memblock allocator, can
1775 * be used
1776 */
1777 map_kernel();
1778 dma_contiguous_remap();
1779 early_fixmap_shutdown();
1780 devicemaps_init(mdesc);
1781 kmap_init();
1782 tcm_init();
1783
1784 top_pmd = pmd_off_k(0xffff0000);
1785
1786 /* allocate the zero page. */
1787 zero_page = early_alloc(PAGE_SIZE);
1788
1789 bootmem_init();
1790
1791 empty_zero_page = virt_to_page(zero_page);
1792 __flush_dcache_folio(NULL, page_folio(empty_zero_page));
1793}
1794
1795void __init early_mm_init(const struct machine_desc *mdesc)
1796{
1797 build_mem_type_table();
1798 early_paging_init(mdesc);
1799}
1800
1801void set_ptes(struct mm_struct *mm, unsigned long addr,
1802 pte_t *ptep, pte_t pteval, unsigned int nr)
1803{
1804 unsigned long ext = 0;
1805
1806 if (addr < TASK_SIZE && pte_valid_user(pteval)) {
1807 if (!pte_special(pteval))
1808 __sync_icache_dcache(pteval);
1809 ext |= PTE_EXT_NG;
1810 }
1811
1812 for (;;) {
1813 set_pte_ext(ptep, pteval, ext);
1814 if (--nr == 0)
1815 break;
1816 ptep++;
1817 pte_val(pteval) += PAGE_SIZE;
1818 }
1819}