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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
19#include <asm/cputype.h>
20#include <asm/sections.h>
21#include <asm/cachetype.h>
22#include <asm/setup.h>
23#include <asm/sizes.h>
24#include <asm/smp_plat.h>
25#include <asm/tlb.h>
26#include <asm/highmem.h>
27#include <asm/traps.h>
28
29#include <asm/mach/arch.h>
30#include <asm/mach/map.h>
31
32#include "mm.h"
33
34/*
35 * empty_zero_page is a special page that is used for
36 * zero-initialized data and COW.
37 */
38struct page *empty_zero_page;
39EXPORT_SYMBOL(empty_zero_page);
40
41/*
42 * The pmd table for the upper-most set of pages.
43 */
44pmd_t *top_pmd;
45
46#define CPOLICY_UNCACHED 0
47#define CPOLICY_BUFFERED 1
48#define CPOLICY_WRITETHROUGH 2
49#define CPOLICY_WRITEBACK 3
50#define CPOLICY_WRITEALLOC 4
51
52static unsigned int cachepolicy __initdata = CPOLICY_WRITEBACK;
53static unsigned int ecc_mask __initdata = 0;
54pgprot_t pgprot_user;
55pgprot_t pgprot_kernel;
56
57EXPORT_SYMBOL(pgprot_user);
58EXPORT_SYMBOL(pgprot_kernel);
59
60struct cachepolicy {
61 const char policy[16];
62 unsigned int cr_mask;
63 unsigned int pmd;
64 pteval_t pte;
65};
66
67static struct cachepolicy cache_policies[] __initdata = {
68 {
69 .policy = "uncached",
70 .cr_mask = CR_W|CR_C,
71 .pmd = PMD_SECT_UNCACHED,
72 .pte = L_PTE_MT_UNCACHED,
73 }, {
74 .policy = "buffered",
75 .cr_mask = CR_C,
76 .pmd = PMD_SECT_BUFFERED,
77 .pte = L_PTE_MT_BUFFERABLE,
78 }, {
79 .policy = "writethrough",
80 .cr_mask = 0,
81 .pmd = PMD_SECT_WT,
82 .pte = L_PTE_MT_WRITETHROUGH,
83 }, {
84 .policy = "writeback",
85 .cr_mask = 0,
86 .pmd = PMD_SECT_WB,
87 .pte = L_PTE_MT_WRITEBACK,
88 }, {
89 .policy = "writealloc",
90 .cr_mask = 0,
91 .pmd = PMD_SECT_WBWA,
92 .pte = L_PTE_MT_WRITEALLOC,
93 }
94};
95
96/*
97 * These are useful for identifying cache coherency
98 * problems by allowing the cache or the cache and
99 * writebuffer to be turned off. (Note: the write
100 * buffer should not be on and the cache off).
101 */
102static int __init early_cachepolicy(char *p)
103{
104 int i;
105
106 for (i = 0; i < ARRAY_SIZE(cache_policies); i++) {
107 int len = strlen(cache_policies[i].policy);
108
109 if (memcmp(p, cache_policies[i].policy, len) == 0) {
110 cachepolicy = i;
111 cr_alignment &= ~cache_policies[i].cr_mask;
112 cr_no_alignment &= ~cache_policies[i].cr_mask;
113 break;
114 }
115 }
116 if (i == ARRAY_SIZE(cache_policies))
117 printk(KERN_ERR "ERROR: unknown or unsupported cache policy\n");
118 /*
119 * This restriction is partly to do with the way we boot; it is
120 * unpredictable to have memory mapped using two different sets of
121 * memory attributes (shared, type, and cache attribs). We can not
122 * change these attributes once the initial assembly has setup the
123 * page tables.
124 */
125 if (cpu_architecture() >= CPU_ARCH_ARMv6) {
126 printk(KERN_WARNING "Only cachepolicy=writeback supported on ARMv6 and later\n");
127 cachepolicy = CPOLICY_WRITEBACK;
128 }
129 flush_cache_all();
130 set_cr(cr_alignment);
131 return 0;
132}
133early_param("cachepolicy", early_cachepolicy);
134
135static int __init early_nocache(char *__unused)
136{
137 char *p = "buffered";
138 printk(KERN_WARNING "nocache is deprecated; use cachepolicy=%s\n", p);
139 early_cachepolicy(p);
140 return 0;
141}
142early_param("nocache", early_nocache);
143
144static int __init early_nowrite(char *__unused)
145{
146 char *p = "uncached";
147 printk(KERN_WARNING "nowb is deprecated; use cachepolicy=%s\n", p);
148 early_cachepolicy(p);
149 return 0;
150}
151early_param("nowb", early_nowrite);
152
153static int __init early_ecc(char *p)
154{
155 if (memcmp(p, "on", 2) == 0)
156 ecc_mask = PMD_PROTECTION;
157 else if (memcmp(p, "off", 3) == 0)
158 ecc_mask = 0;
159 return 0;
160}
161early_param("ecc", early_ecc);
162
163static int __init noalign_setup(char *__unused)
164{
165 cr_alignment &= ~CR_A;
166 cr_no_alignment &= ~CR_A;
167 set_cr(cr_alignment);
168 return 1;
169}
170__setup("noalign", noalign_setup);
171
172#ifndef CONFIG_SMP
173void adjust_cr(unsigned long mask, unsigned long set)
174{
175 unsigned long flags;
176
177 mask &= ~CR_A;
178
179 set &= mask;
180
181 local_irq_save(flags);
182
183 cr_no_alignment = (cr_no_alignment & ~mask) | set;
184 cr_alignment = (cr_alignment & ~mask) | set;
185
186 set_cr((get_cr() & ~mask) | set);
187
188 local_irq_restore(flags);
189}
190#endif
191
192#define PROT_PTE_DEVICE L_PTE_PRESENT|L_PTE_YOUNG|L_PTE_DIRTY|L_PTE_XN
193#define PROT_SECT_DEVICE PMD_TYPE_SECT|PMD_SECT_AP_WRITE
194
195static struct mem_type mem_types[] = {
196 [MT_DEVICE] = { /* Strongly ordered / ARMv6 shared device */
197 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_SHARED |
198 L_PTE_SHARED,
199 .prot_l1 = PMD_TYPE_TABLE,
200 .prot_sect = PROT_SECT_DEVICE | PMD_SECT_S,
201 .domain = DOMAIN_IO,
202 },
203 [MT_DEVICE_NONSHARED] = { /* ARMv6 non-shared device */
204 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_NONSHARED,
205 .prot_l1 = PMD_TYPE_TABLE,
206 .prot_sect = PROT_SECT_DEVICE,
207 .domain = DOMAIN_IO,
208 },
209 [MT_DEVICE_CACHED] = { /* ioremap_cached */
210 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_CACHED,
211 .prot_l1 = PMD_TYPE_TABLE,
212 .prot_sect = PROT_SECT_DEVICE | PMD_SECT_WB,
213 .domain = DOMAIN_IO,
214 },
215 [MT_DEVICE_WC] = { /* ioremap_wc */
216 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_WC,
217 .prot_l1 = PMD_TYPE_TABLE,
218 .prot_sect = PROT_SECT_DEVICE,
219 .domain = DOMAIN_IO,
220 },
221 [MT_UNCACHED] = {
222 .prot_pte = PROT_PTE_DEVICE,
223 .prot_l1 = PMD_TYPE_TABLE,
224 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
225 .domain = DOMAIN_IO,
226 },
227 [MT_CACHECLEAN] = {
228 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
229 .domain = DOMAIN_KERNEL,
230 },
231 [MT_MINICLEAN] = {
232 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN | PMD_SECT_MINICACHE,
233 .domain = DOMAIN_KERNEL,
234 },
235 [MT_LOW_VECTORS] = {
236 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
237 L_PTE_RDONLY,
238 .prot_l1 = PMD_TYPE_TABLE,
239 .domain = DOMAIN_USER,
240 },
241 [MT_HIGH_VECTORS] = {
242 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
243 L_PTE_USER | L_PTE_RDONLY,
244 .prot_l1 = PMD_TYPE_TABLE,
245 .domain = DOMAIN_USER,
246 },
247 [MT_MEMORY] = {
248 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
249 .prot_l1 = PMD_TYPE_TABLE,
250 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
251 .domain = DOMAIN_KERNEL,
252 },
253 [MT_ROM] = {
254 .prot_sect = PMD_TYPE_SECT,
255 .domain = DOMAIN_KERNEL,
256 },
257 [MT_MEMORY_NONCACHED] = {
258 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
259 L_PTE_MT_BUFFERABLE,
260 .prot_l1 = PMD_TYPE_TABLE,
261 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
262 .domain = DOMAIN_KERNEL,
263 },
264 [MT_MEMORY_DTCM] = {
265 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
266 L_PTE_XN,
267 .prot_l1 = PMD_TYPE_TABLE,
268 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
269 .domain = DOMAIN_KERNEL,
270 },
271 [MT_MEMORY_ITCM] = {
272 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
273 .prot_l1 = PMD_TYPE_TABLE,
274 .domain = DOMAIN_KERNEL,
275 },
276};
277
278const struct mem_type *get_mem_type(unsigned int type)
279{
280 return type < ARRAY_SIZE(mem_types) ? &mem_types[type] : NULL;
281}
282EXPORT_SYMBOL(get_mem_type);
283
284/*
285 * Adjust the PMD section entries according to the CPU in use.
286 */
287static void __init build_mem_type_table(void)
288{
289 struct cachepolicy *cp;
290 unsigned int cr = get_cr();
291 unsigned int user_pgprot, kern_pgprot, vecs_pgprot;
292 int cpu_arch = cpu_architecture();
293 int i;
294
295 if (cpu_arch < CPU_ARCH_ARMv6) {
296#if defined(CONFIG_CPU_DCACHE_DISABLE)
297 if (cachepolicy > CPOLICY_BUFFERED)
298 cachepolicy = CPOLICY_BUFFERED;
299#elif defined(CONFIG_CPU_DCACHE_WRITETHROUGH)
300 if (cachepolicy > CPOLICY_WRITETHROUGH)
301 cachepolicy = CPOLICY_WRITETHROUGH;
302#endif
303 }
304 if (cpu_arch < CPU_ARCH_ARMv5) {
305 if (cachepolicy >= CPOLICY_WRITEALLOC)
306 cachepolicy = CPOLICY_WRITEBACK;
307 ecc_mask = 0;
308 }
309 if (is_smp())
310 cachepolicy = CPOLICY_WRITEALLOC;
311
312 /*
313 * Strip out features not present on earlier architectures.
314 * Pre-ARMv5 CPUs don't have TEX bits. Pre-ARMv6 CPUs or those
315 * without extended page tables don't have the 'Shared' bit.
316 */
317 if (cpu_arch < CPU_ARCH_ARMv5)
318 for (i = 0; i < ARRAY_SIZE(mem_types); i++)
319 mem_types[i].prot_sect &= ~PMD_SECT_TEX(7);
320 if ((cpu_arch < CPU_ARCH_ARMv6 || !(cr & CR_XP)) && !cpu_is_xsc3())
321 for (i = 0; i < ARRAY_SIZE(mem_types); i++)
322 mem_types[i].prot_sect &= ~PMD_SECT_S;
323
324 /*
325 * ARMv5 and lower, bit 4 must be set for page tables (was: cache
326 * "update-able on write" bit on ARM610). However, Xscale and
327 * Xscale3 require this bit to be cleared.
328 */
329 if (cpu_is_xscale() || cpu_is_xsc3()) {
330 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
331 mem_types[i].prot_sect &= ~PMD_BIT4;
332 mem_types[i].prot_l1 &= ~PMD_BIT4;
333 }
334 } else if (cpu_arch < CPU_ARCH_ARMv6) {
335 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
336 if (mem_types[i].prot_l1)
337 mem_types[i].prot_l1 |= PMD_BIT4;
338 if (mem_types[i].prot_sect)
339 mem_types[i].prot_sect |= PMD_BIT4;
340 }
341 }
342
343 /*
344 * Mark the device areas according to the CPU/architecture.
345 */
346 if (cpu_is_xsc3() || (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP))) {
347 if (!cpu_is_xsc3()) {
348 /*
349 * Mark device regions on ARMv6+ as execute-never
350 * to prevent speculative instruction fetches.
351 */
352 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_XN;
353 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_XN;
354 mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_XN;
355 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_XN;
356 }
357 if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
358 /*
359 * For ARMv7 with TEX remapping,
360 * - shared device is SXCB=1100
361 * - nonshared device is SXCB=0100
362 * - write combine device mem is SXCB=0001
363 * (Uncached Normal memory)
364 */
365 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_TEX(1);
366 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(1);
367 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_BUFFERABLE;
368 } else if (cpu_is_xsc3()) {
369 /*
370 * For Xscale3,
371 * - shared device is TEXCB=00101
372 * - nonshared device is TEXCB=01000
373 * - write combine device mem is TEXCB=00100
374 * (Inner/Outer Uncacheable in xsc3 parlance)
375 */
376 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_TEX(1) | PMD_SECT_BUFFERED;
377 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(2);
378 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1);
379 } else {
380 /*
381 * For ARMv6 and ARMv7 without TEX remapping,
382 * - shared device is TEXCB=00001
383 * - nonshared device is TEXCB=01000
384 * - write combine device mem is TEXCB=00100
385 * (Uncached Normal in ARMv6 parlance).
386 */
387 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_BUFFERED;
388 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(2);
389 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1);
390 }
391 } else {
392 /*
393 * On others, write combining is "Uncached/Buffered"
394 */
395 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_BUFFERABLE;
396 }
397
398 /*
399 * Now deal with the memory-type mappings
400 */
401 cp = &cache_policies[cachepolicy];
402 vecs_pgprot = kern_pgprot = user_pgprot = cp->pte;
403
404 /*
405 * Only use write-through for non-SMP systems
406 */
407 if (!is_smp() && cpu_arch >= CPU_ARCH_ARMv5 && cachepolicy > CPOLICY_WRITETHROUGH)
408 vecs_pgprot = cache_policies[CPOLICY_WRITETHROUGH].pte;
409
410 /*
411 * Enable CPU-specific coherency if supported.
412 * (Only available on XSC3 at the moment.)
413 */
414 if (arch_is_coherent() && cpu_is_xsc3()) {
415 mem_types[MT_MEMORY].prot_sect |= PMD_SECT_S;
416 mem_types[MT_MEMORY].prot_pte |= L_PTE_SHARED;
417 mem_types[MT_MEMORY_NONCACHED].prot_sect |= PMD_SECT_S;
418 mem_types[MT_MEMORY_NONCACHED].prot_pte |= L_PTE_SHARED;
419 }
420 /*
421 * ARMv6 and above have extended page tables.
422 */
423 if (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP)) {
424 /*
425 * Mark cache clean areas and XIP ROM read only
426 * from SVC mode and no access from userspace.
427 */
428 mem_types[MT_ROM].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
429 mem_types[MT_MINICLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
430 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
431
432 if (is_smp()) {
433 /*
434 * Mark memory with the "shared" attribute
435 * for SMP systems
436 */
437 user_pgprot |= L_PTE_SHARED;
438 kern_pgprot |= L_PTE_SHARED;
439 vecs_pgprot |= L_PTE_SHARED;
440 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_S;
441 mem_types[MT_DEVICE_WC].prot_pte |= L_PTE_SHARED;
442 mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_S;
443 mem_types[MT_DEVICE_CACHED].prot_pte |= L_PTE_SHARED;
444 mem_types[MT_MEMORY].prot_sect |= PMD_SECT_S;
445 mem_types[MT_MEMORY].prot_pte |= L_PTE_SHARED;
446 mem_types[MT_MEMORY_NONCACHED].prot_sect |= PMD_SECT_S;
447 mem_types[MT_MEMORY_NONCACHED].prot_pte |= L_PTE_SHARED;
448 }
449 }
450
451 /*
452 * Non-cacheable Normal - intended for memory areas that must
453 * not cause dirty cache line writebacks when used
454 */
455 if (cpu_arch >= CPU_ARCH_ARMv6) {
456 if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
457 /* Non-cacheable Normal is XCB = 001 */
458 mem_types[MT_MEMORY_NONCACHED].prot_sect |=
459 PMD_SECT_BUFFERED;
460 } else {
461 /* For both ARMv6 and non-TEX-remapping ARMv7 */
462 mem_types[MT_MEMORY_NONCACHED].prot_sect |=
463 PMD_SECT_TEX(1);
464 }
465 } else {
466 mem_types[MT_MEMORY_NONCACHED].prot_sect |= PMD_SECT_BUFFERABLE;
467 }
468
469 for (i = 0; i < 16; i++) {
470 unsigned long v = pgprot_val(protection_map[i]);
471 protection_map[i] = __pgprot(v | user_pgprot);
472 }
473
474 mem_types[MT_LOW_VECTORS].prot_pte |= vecs_pgprot;
475 mem_types[MT_HIGH_VECTORS].prot_pte |= vecs_pgprot;
476
477 pgprot_user = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | user_pgprot);
478 pgprot_kernel = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG |
479 L_PTE_DIRTY | kern_pgprot);
480
481 mem_types[MT_LOW_VECTORS].prot_l1 |= ecc_mask;
482 mem_types[MT_HIGH_VECTORS].prot_l1 |= ecc_mask;
483 mem_types[MT_MEMORY].prot_sect |= ecc_mask | cp->pmd;
484 mem_types[MT_MEMORY].prot_pte |= kern_pgprot;
485 mem_types[MT_MEMORY_NONCACHED].prot_sect |= ecc_mask;
486 mem_types[MT_ROM].prot_sect |= cp->pmd;
487
488 switch (cp->pmd) {
489 case PMD_SECT_WT:
490 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WT;
491 break;
492 case PMD_SECT_WB:
493 case PMD_SECT_WBWA:
494 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WB;
495 break;
496 }
497 printk("Memory policy: ECC %sabled, Data cache %s\n",
498 ecc_mask ? "en" : "dis", cp->policy);
499
500 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
501 struct mem_type *t = &mem_types[i];
502 if (t->prot_l1)
503 t->prot_l1 |= PMD_DOMAIN(t->domain);
504 if (t->prot_sect)
505 t->prot_sect |= PMD_DOMAIN(t->domain);
506 }
507}
508
509#ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
510pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
511 unsigned long size, pgprot_t vma_prot)
512{
513 if (!pfn_valid(pfn))
514 return pgprot_noncached(vma_prot);
515 else if (file->f_flags & O_SYNC)
516 return pgprot_writecombine(vma_prot);
517 return vma_prot;
518}
519EXPORT_SYMBOL(phys_mem_access_prot);
520#endif
521
522#define vectors_base() (vectors_high() ? 0xffff0000 : 0)
523
524static void __init *early_alloc(unsigned long sz)
525{
526 void *ptr = __va(memblock_alloc(sz, sz));
527 memset(ptr, 0, sz);
528 return ptr;
529}
530
531static pte_t * __init early_pte_alloc(pmd_t *pmd, unsigned long addr, unsigned long prot)
532{
533 if (pmd_none(*pmd)) {
534 pte_t *pte = early_alloc(PTE_HWTABLE_OFF + PTE_HWTABLE_SIZE);
535 __pmd_populate(pmd, __pa(pte), prot);
536 }
537 BUG_ON(pmd_bad(*pmd));
538 return pte_offset_kernel(pmd, addr);
539}
540
541static void __init alloc_init_pte(pmd_t *pmd, unsigned long addr,
542 unsigned long end, unsigned long pfn,
543 const struct mem_type *type)
544{
545 pte_t *pte = early_pte_alloc(pmd, addr, type->prot_l1);
546 do {
547 set_pte_ext(pte, pfn_pte(pfn, __pgprot(type->prot_pte)), 0);
548 pfn++;
549 } while (pte++, addr += PAGE_SIZE, addr != end);
550}
551
552static void __init alloc_init_section(pud_t *pud, unsigned long addr,
553 unsigned long end, phys_addr_t phys,
554 const struct mem_type *type)
555{
556 pmd_t *pmd = pmd_offset(pud, addr);
557
558 /*
559 * Try a section mapping - end, addr and phys must all be aligned
560 * to a section boundary. Note that PMDs refer to the individual
561 * L1 entries, whereas PGDs refer to a group of L1 entries making
562 * up one logical pointer to an L2 table.
563 */
564 if (((addr | end | phys) & ~SECTION_MASK) == 0) {
565 pmd_t *p = pmd;
566
567 if (addr & SECTION_SIZE)
568 pmd++;
569
570 do {
571 *pmd = __pmd(phys | type->prot_sect);
572 phys += SECTION_SIZE;
573 } while (pmd++, addr += SECTION_SIZE, addr != end);
574
575 flush_pmd_entry(p);
576 } else {
577 /*
578 * No need to loop; pte's aren't interested in the
579 * individual L1 entries.
580 */
581 alloc_init_pte(pmd, addr, end, __phys_to_pfn(phys), type);
582 }
583}
584
585static void alloc_init_pud(pgd_t *pgd, unsigned long addr, unsigned long end,
586 unsigned long phys, const struct mem_type *type)
587{
588 pud_t *pud = pud_offset(pgd, addr);
589 unsigned long next;
590
591 do {
592 next = pud_addr_end(addr, end);
593 alloc_init_section(pud, addr, next, phys, type);
594 phys += next - addr;
595 } while (pud++, addr = next, addr != end);
596}
597
598static void __init create_36bit_mapping(struct map_desc *md,
599 const struct mem_type *type)
600{
601 unsigned long addr, length, end;
602 phys_addr_t phys;
603 pgd_t *pgd;
604
605 addr = md->virtual;
606 phys = __pfn_to_phys(md->pfn);
607 length = PAGE_ALIGN(md->length);
608
609 if (!(cpu_architecture() >= CPU_ARCH_ARMv6 || cpu_is_xsc3())) {
610 printk(KERN_ERR "MM: CPU does not support supersection "
611 "mapping for 0x%08llx at 0x%08lx\n",
612 (long long)__pfn_to_phys((u64)md->pfn), addr);
613 return;
614 }
615
616 /* N.B. ARMv6 supersections are only defined to work with domain 0.
617 * Since domain assignments can in fact be arbitrary, the
618 * 'domain == 0' check below is required to insure that ARMv6
619 * supersections are only allocated for domain 0 regardless
620 * of the actual domain assignments in use.
621 */
622 if (type->domain) {
623 printk(KERN_ERR "MM: invalid domain in supersection "
624 "mapping for 0x%08llx at 0x%08lx\n",
625 (long long)__pfn_to_phys((u64)md->pfn), addr);
626 return;
627 }
628
629 if ((addr | length | __pfn_to_phys(md->pfn)) & ~SUPERSECTION_MASK) {
630 printk(KERN_ERR "MM: cannot create mapping for 0x%08llx"
631 " at 0x%08lx invalid alignment\n",
632 (long long)__pfn_to_phys((u64)md->pfn), addr);
633 return;
634 }
635
636 /*
637 * Shift bits [35:32] of address into bits [23:20] of PMD
638 * (See ARMv6 spec).
639 */
640 phys |= (((md->pfn >> (32 - PAGE_SHIFT)) & 0xF) << 20);
641
642 pgd = pgd_offset_k(addr);
643 end = addr + length;
644 do {
645 pud_t *pud = pud_offset(pgd, addr);
646 pmd_t *pmd = pmd_offset(pud, addr);
647 int i;
648
649 for (i = 0; i < 16; i++)
650 *pmd++ = __pmd(phys | type->prot_sect | PMD_SECT_SUPER);
651
652 addr += SUPERSECTION_SIZE;
653 phys += SUPERSECTION_SIZE;
654 pgd += SUPERSECTION_SIZE >> PGDIR_SHIFT;
655 } while (addr != end);
656}
657
658/*
659 * Create the page directory entries and any necessary
660 * page tables for the mapping specified by `md'. We
661 * are able to cope here with varying sizes and address
662 * offsets, and we take full advantage of sections and
663 * supersections.
664 */
665static void __init create_mapping(struct map_desc *md)
666{
667 unsigned long addr, length, end;
668 phys_addr_t phys;
669 const struct mem_type *type;
670 pgd_t *pgd;
671
672 if (md->virtual != vectors_base() && md->virtual < TASK_SIZE) {
673 printk(KERN_WARNING "BUG: not creating mapping for 0x%08llx"
674 " at 0x%08lx in user region\n",
675 (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
676 return;
677 }
678
679 if ((md->type == MT_DEVICE || md->type == MT_ROM) &&
680 md->virtual >= PAGE_OFFSET && md->virtual < VMALLOC_END) {
681 printk(KERN_WARNING "BUG: mapping for 0x%08llx"
682 " at 0x%08lx overlaps vmalloc space\n",
683 (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
684 }
685
686 type = &mem_types[md->type];
687
688 /*
689 * Catch 36-bit addresses
690 */
691 if (md->pfn >= 0x100000) {
692 create_36bit_mapping(md, type);
693 return;
694 }
695
696 addr = md->virtual & PAGE_MASK;
697 phys = __pfn_to_phys(md->pfn);
698 length = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK));
699
700 if (type->prot_l1 == 0 && ((addr | phys | length) & ~SECTION_MASK)) {
701 printk(KERN_WARNING "BUG: map for 0x%08llx at 0x%08lx can not "
702 "be mapped using pages, ignoring.\n",
703 (long long)__pfn_to_phys(md->pfn), addr);
704 return;
705 }
706
707 pgd = pgd_offset_k(addr);
708 end = addr + length;
709 do {
710 unsigned long next = pgd_addr_end(addr, end);
711
712 alloc_init_pud(pgd, addr, next, phys, type);
713
714 phys += next - addr;
715 addr = next;
716 } while (pgd++, addr != end);
717}
718
719/*
720 * Create the architecture specific mappings
721 */
722void __init iotable_init(struct map_desc *io_desc, int nr)
723{
724 int i;
725
726 for (i = 0; i < nr; i++)
727 create_mapping(io_desc + i);
728}
729
730static void * __initdata vmalloc_min = (void *)(VMALLOC_END - SZ_128M);
731
732/*
733 * vmalloc=size forces the vmalloc area to be exactly 'size'
734 * bytes. This can be used to increase (or decrease) the vmalloc
735 * area - the default is 128m.
736 */
737static int __init early_vmalloc(char *arg)
738{
739 unsigned long vmalloc_reserve = memparse(arg, NULL);
740
741 if (vmalloc_reserve < SZ_16M) {
742 vmalloc_reserve = SZ_16M;
743 printk(KERN_WARNING
744 "vmalloc area too small, limiting to %luMB\n",
745 vmalloc_reserve >> 20);
746 }
747
748 if (vmalloc_reserve > VMALLOC_END - (PAGE_OFFSET + SZ_32M)) {
749 vmalloc_reserve = VMALLOC_END - (PAGE_OFFSET + SZ_32M);
750 printk(KERN_WARNING
751 "vmalloc area is too big, limiting to %luMB\n",
752 vmalloc_reserve >> 20);
753 }
754
755 vmalloc_min = (void *)(VMALLOC_END - vmalloc_reserve);
756 return 0;
757}
758early_param("vmalloc", early_vmalloc);
759
760static phys_addr_t lowmem_limit __initdata = 0;
761
762void __init sanity_check_meminfo(void)
763{
764 int i, j, highmem = 0;
765
766 for (i = 0, j = 0; i < meminfo.nr_banks; i++) {
767 struct membank *bank = &meminfo.bank[j];
768 *bank = meminfo.bank[i];
769
770#ifdef CONFIG_HIGHMEM
771 if (__va(bank->start) >= vmalloc_min ||
772 __va(bank->start) < (void *)PAGE_OFFSET)
773 highmem = 1;
774
775 bank->highmem = highmem;
776
777 /*
778 * Split those memory banks which are partially overlapping
779 * the vmalloc area greatly simplifying things later.
780 */
781 if (__va(bank->start) < vmalloc_min &&
782 bank->size > vmalloc_min - __va(bank->start)) {
783 if (meminfo.nr_banks >= NR_BANKS) {
784 printk(KERN_CRIT "NR_BANKS too low, "
785 "ignoring high memory\n");
786 } else {
787 memmove(bank + 1, bank,
788 (meminfo.nr_banks - i) * sizeof(*bank));
789 meminfo.nr_banks++;
790 i++;
791 bank[1].size -= vmalloc_min - __va(bank->start);
792 bank[1].start = __pa(vmalloc_min - 1) + 1;
793 bank[1].highmem = highmem = 1;
794 j++;
795 }
796 bank->size = vmalloc_min - __va(bank->start);
797 }
798#else
799 bank->highmem = highmem;
800
801 /*
802 * Check whether this memory bank would entirely overlap
803 * the vmalloc area.
804 */
805 if (__va(bank->start) >= vmalloc_min ||
806 __va(bank->start) < (void *)PAGE_OFFSET) {
807 printk(KERN_NOTICE "Ignoring RAM at %.8llx-%.8llx "
808 "(vmalloc region overlap).\n",
809 (unsigned long long)bank->start,
810 (unsigned long long)bank->start + bank->size - 1);
811 continue;
812 }
813
814 /*
815 * Check whether this memory bank would partially overlap
816 * the vmalloc area.
817 */
818 if (__va(bank->start + bank->size) > vmalloc_min ||
819 __va(bank->start + bank->size) < __va(bank->start)) {
820 unsigned long newsize = vmalloc_min - __va(bank->start);
821 printk(KERN_NOTICE "Truncating RAM at %.8llx-%.8llx "
822 "to -%.8llx (vmalloc region overlap).\n",
823 (unsigned long long)bank->start,
824 (unsigned long long)bank->start + bank->size - 1,
825 (unsigned long long)bank->start + newsize - 1);
826 bank->size = newsize;
827 }
828#endif
829 if (!bank->highmem && bank->start + bank->size > lowmem_limit)
830 lowmem_limit = bank->start + bank->size;
831
832 j++;
833 }
834#ifdef CONFIG_HIGHMEM
835 if (highmem) {
836 const char *reason = NULL;
837
838 if (cache_is_vipt_aliasing()) {
839 /*
840 * Interactions between kmap and other mappings
841 * make highmem support with aliasing VIPT caches
842 * rather difficult.
843 */
844 reason = "with VIPT aliasing cache";
845 }
846 if (reason) {
847 printk(KERN_CRIT "HIGHMEM is not supported %s, ignoring high memory\n",
848 reason);
849 while (j > 0 && meminfo.bank[j - 1].highmem)
850 j--;
851 }
852 }
853#endif
854 meminfo.nr_banks = j;
855 memblock_set_current_limit(lowmem_limit);
856}
857
858static inline void prepare_page_table(void)
859{
860 unsigned long addr;
861 phys_addr_t end;
862
863 /*
864 * Clear out all the mappings below the kernel image.
865 */
866 for (addr = 0; addr < MODULES_VADDR; addr += PGDIR_SIZE)
867 pmd_clear(pmd_off_k(addr));
868
869#ifdef CONFIG_XIP_KERNEL
870 /* The XIP kernel is mapped in the module area -- skip over it */
871 addr = ((unsigned long)_etext + PGDIR_SIZE - 1) & PGDIR_MASK;
872#endif
873 for ( ; addr < PAGE_OFFSET; addr += PGDIR_SIZE)
874 pmd_clear(pmd_off_k(addr));
875
876 /*
877 * Find the end of the first block of lowmem.
878 */
879 end = memblock.memory.regions[0].base + memblock.memory.regions[0].size;
880 if (end >= lowmem_limit)
881 end = lowmem_limit;
882
883 /*
884 * Clear out all the kernel space mappings, except for the first
885 * memory bank, up to the end of the vmalloc region.
886 */
887 for (addr = __phys_to_virt(end);
888 addr < VMALLOC_END; addr += PGDIR_SIZE)
889 pmd_clear(pmd_off_k(addr));
890}
891
892/*
893 * Reserve the special regions of memory
894 */
895void __init arm_mm_memblock_reserve(void)
896{
897 /*
898 * Reserve the page tables. These are already in use,
899 * and can only be in node 0.
900 */
901 memblock_reserve(__pa(swapper_pg_dir), PTRS_PER_PGD * sizeof(pgd_t));
902
903#ifdef CONFIG_SA1111
904 /*
905 * Because of the SA1111 DMA bug, we want to preserve our
906 * precious DMA-able memory...
907 */
908 memblock_reserve(PHYS_OFFSET, __pa(swapper_pg_dir) - PHYS_OFFSET);
909#endif
910}
911
912/*
913 * Set up device the mappings. Since we clear out the page tables for all
914 * mappings above VMALLOC_END, we will remove any debug device mappings.
915 * This means you have to be careful how you debug this function, or any
916 * called function. This means you can't use any function or debugging
917 * method which may touch any device, otherwise the kernel _will_ crash.
918 */
919static void __init devicemaps_init(struct machine_desc *mdesc)
920{
921 struct map_desc map;
922 unsigned long addr;
923
924 /*
925 * Allocate the vector page early.
926 */
927 vectors_page = early_alloc(PAGE_SIZE);
928
929 for (addr = VMALLOC_END; addr; addr += PGDIR_SIZE)
930 pmd_clear(pmd_off_k(addr));
931
932 /*
933 * Map the kernel if it is XIP.
934 * It is always first in the modulearea.
935 */
936#ifdef CONFIG_XIP_KERNEL
937 map.pfn = __phys_to_pfn(CONFIG_XIP_PHYS_ADDR & SECTION_MASK);
938 map.virtual = MODULES_VADDR;
939 map.length = ((unsigned long)_etext - map.virtual + ~SECTION_MASK) & SECTION_MASK;
940 map.type = MT_ROM;
941 create_mapping(&map);
942#endif
943
944 /*
945 * Map the cache flushing regions.
946 */
947#ifdef FLUSH_BASE
948 map.pfn = __phys_to_pfn(FLUSH_BASE_PHYS);
949 map.virtual = FLUSH_BASE;
950 map.length = SZ_1M;
951 map.type = MT_CACHECLEAN;
952 create_mapping(&map);
953#endif
954#ifdef FLUSH_BASE_MINICACHE
955 map.pfn = __phys_to_pfn(FLUSH_BASE_PHYS + SZ_1M);
956 map.virtual = FLUSH_BASE_MINICACHE;
957 map.length = SZ_1M;
958 map.type = MT_MINICLEAN;
959 create_mapping(&map);
960#endif
961
962 /*
963 * Create a mapping for the machine vectors at the high-vectors
964 * location (0xffff0000). If we aren't using high-vectors, also
965 * create a mapping at the low-vectors virtual address.
966 */
967 map.pfn = __phys_to_pfn(virt_to_phys(vectors_page));
968 map.virtual = 0xffff0000;
969 map.length = PAGE_SIZE;
970 map.type = MT_HIGH_VECTORS;
971 create_mapping(&map);
972
973 if (!vectors_high()) {
974 map.virtual = 0;
975 map.type = MT_LOW_VECTORS;
976 create_mapping(&map);
977 }
978
979 /*
980 * Ask the machine support to map in the statically mapped devices.
981 */
982 if (mdesc->map_io)
983 mdesc->map_io();
984
985 /*
986 * Finally flush the caches and tlb to ensure that we're in a
987 * consistent state wrt the writebuffer. This also ensures that
988 * any write-allocated cache lines in the vector page are written
989 * back. After this point, we can start to touch devices again.
990 */
991 local_flush_tlb_all();
992 flush_cache_all();
993}
994
995static void __init kmap_init(void)
996{
997#ifdef CONFIG_HIGHMEM
998 pkmap_page_table = early_pte_alloc(pmd_off_k(PKMAP_BASE),
999 PKMAP_BASE, _PAGE_KERNEL_TABLE);
1000#endif
1001}
1002
1003static void __init map_lowmem(void)
1004{
1005 struct memblock_region *reg;
1006
1007 /* Map all the lowmem memory banks. */
1008 for_each_memblock(memory, reg) {
1009 phys_addr_t start = reg->base;
1010 phys_addr_t end = start + reg->size;
1011 struct map_desc map;
1012
1013 if (end > lowmem_limit)
1014 end = lowmem_limit;
1015 if (start >= end)
1016 break;
1017
1018 map.pfn = __phys_to_pfn(start);
1019 map.virtual = __phys_to_virt(start);
1020 map.length = end - start;
1021 map.type = MT_MEMORY;
1022
1023 create_mapping(&map);
1024 }
1025}
1026
1027/*
1028 * paging_init() sets up the page tables, initialises the zone memory
1029 * maps, and sets up the zero page, bad page and bad page tables.
1030 */
1031void __init paging_init(struct machine_desc *mdesc)
1032{
1033 void *zero_page;
1034
1035 memblock_set_current_limit(lowmem_limit);
1036
1037 build_mem_type_table();
1038 prepare_page_table();
1039 map_lowmem();
1040 devicemaps_init(mdesc);
1041 kmap_init();
1042
1043 top_pmd = pmd_off_k(0xffff0000);
1044
1045 /* allocate the zero page. */
1046 zero_page = early_alloc(PAGE_SIZE);
1047
1048 bootmem_init();
1049
1050 empty_zero_page = virt_to_page(zero_page);
1051 __flush_dcache_page(NULL, empty_zero_page);
1052}
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/sections.h>
21#include <asm/cachetype.h>
22#include <asm/fixmap.h>
23#include <asm/sections.h>
24#include <asm/setup.h>
25#include <asm/smp_plat.h>
26#include <asm/tlb.h>
27#include <asm/highmem.h>
28#include <asm/system_info.h>
29#include <asm/traps.h>
30#include <asm/procinfo.h>
31#include <asm/memory.h>
32
33#include <asm/mach/arch.h>
34#include <asm/mach/map.h>
35#include <asm/mach/pci.h>
36#include <asm/fixmap.h>
37
38#include "fault.h"
39#include "mm.h"
40#include "tcm.h"
41
42/*
43 * empty_zero_page is a special page that is used for
44 * zero-initialized data and COW.
45 */
46struct page *empty_zero_page;
47EXPORT_SYMBOL(empty_zero_page);
48
49/*
50 * The pmd table for the upper-most set of pages.
51 */
52pmd_t *top_pmd;
53
54pmdval_t user_pmd_table = _PAGE_USER_TABLE;
55
56#define CPOLICY_UNCACHED 0
57#define CPOLICY_BUFFERED 1
58#define CPOLICY_WRITETHROUGH 2
59#define CPOLICY_WRITEBACK 3
60#define CPOLICY_WRITEALLOC 4
61
62static unsigned int cachepolicy __initdata = CPOLICY_WRITEBACK;
63static unsigned int ecc_mask __initdata = 0;
64pgprot_t pgprot_user;
65pgprot_t pgprot_kernel;
66pgprot_t pgprot_hyp_device;
67pgprot_t pgprot_s2;
68pgprot_t pgprot_s2_device;
69
70EXPORT_SYMBOL(pgprot_user);
71EXPORT_SYMBOL(pgprot_kernel);
72
73struct cachepolicy {
74 const char policy[16];
75 unsigned int cr_mask;
76 pmdval_t pmd;
77 pteval_t pte;
78 pteval_t pte_s2;
79};
80
81#ifdef CONFIG_ARM_LPAE
82#define s2_policy(policy) policy
83#else
84#define s2_policy(policy) 0
85#endif
86
87unsigned long kimage_voffset __ro_after_init;
88
89static struct cachepolicy cache_policies[] __initdata = {
90 {
91 .policy = "uncached",
92 .cr_mask = CR_W|CR_C,
93 .pmd = PMD_SECT_UNCACHED,
94 .pte = L_PTE_MT_UNCACHED,
95 .pte_s2 = s2_policy(L_PTE_S2_MT_UNCACHED),
96 }, {
97 .policy = "buffered",
98 .cr_mask = CR_C,
99 .pmd = PMD_SECT_BUFFERED,
100 .pte = L_PTE_MT_BUFFERABLE,
101 .pte_s2 = s2_policy(L_PTE_S2_MT_UNCACHED),
102 }, {
103 .policy = "writethrough",
104 .cr_mask = 0,
105 .pmd = PMD_SECT_WT,
106 .pte = L_PTE_MT_WRITETHROUGH,
107 .pte_s2 = s2_policy(L_PTE_S2_MT_WRITETHROUGH),
108 }, {
109 .policy = "writeback",
110 .cr_mask = 0,
111 .pmd = PMD_SECT_WB,
112 .pte = L_PTE_MT_WRITEBACK,
113 .pte_s2 = s2_policy(L_PTE_S2_MT_WRITEBACK),
114 }, {
115 .policy = "writealloc",
116 .cr_mask = 0,
117 .pmd = PMD_SECT_WBWA,
118 .pte = L_PTE_MT_WRITEALLOC,
119 .pte_s2 = s2_policy(L_PTE_S2_MT_WRITEBACK),
120 }
121};
122
123#ifdef CONFIG_CPU_CP15
124static unsigned long initial_pmd_value __initdata = 0;
125
126/*
127 * Initialise the cache_policy variable with the initial state specified
128 * via the "pmd" value. This is used to ensure that on ARMv6 and later,
129 * the C code sets the page tables up with the same policy as the head
130 * assembly code, which avoids an illegal state where the TLBs can get
131 * confused. See comments in early_cachepolicy() for more information.
132 */
133void __init init_default_cache_policy(unsigned long pmd)
134{
135 int i;
136
137 initial_pmd_value = pmd;
138
139 pmd &= PMD_SECT_CACHE_MASK;
140
141 for (i = 0; i < ARRAY_SIZE(cache_policies); i++)
142 if (cache_policies[i].pmd == pmd) {
143 cachepolicy = i;
144 break;
145 }
146
147 if (i == ARRAY_SIZE(cache_policies))
148 pr_err("ERROR: could not find cache policy\n");
149}
150
151/*
152 * These are useful for identifying cache coherency problems by allowing
153 * the cache or the cache and writebuffer to be turned off. (Note: the
154 * write buffer should not be on and the cache off).
155 */
156static int __init early_cachepolicy(char *p)
157{
158 int i, selected = -1;
159
160 for (i = 0; i < ARRAY_SIZE(cache_policies); i++) {
161 int len = strlen(cache_policies[i].policy);
162
163 if (memcmp(p, cache_policies[i].policy, len) == 0) {
164 selected = i;
165 break;
166 }
167 }
168
169 if (selected == -1)
170 pr_err("ERROR: unknown or unsupported cache policy\n");
171
172 /*
173 * This restriction is partly to do with the way we boot; it is
174 * unpredictable to have memory mapped using two different sets of
175 * memory attributes (shared, type, and cache attribs). We can not
176 * change these attributes once the initial assembly has setup the
177 * page tables.
178 */
179 if (cpu_architecture() >= CPU_ARCH_ARMv6 && selected != cachepolicy) {
180 pr_warn("Only cachepolicy=%s supported on ARMv6 and later\n",
181 cache_policies[cachepolicy].policy);
182 return 0;
183 }
184
185 if (selected != cachepolicy) {
186 unsigned long cr = __clear_cr(cache_policies[selected].cr_mask);
187 cachepolicy = selected;
188 flush_cache_all();
189 set_cr(cr);
190 }
191 return 0;
192}
193early_param("cachepolicy", early_cachepolicy);
194
195static int __init early_nocache(char *__unused)
196{
197 char *p = "buffered";
198 pr_warn("nocache is deprecated; use cachepolicy=%s\n", p);
199 early_cachepolicy(p);
200 return 0;
201}
202early_param("nocache", early_nocache);
203
204static int __init early_nowrite(char *__unused)
205{
206 char *p = "uncached";
207 pr_warn("nowb is deprecated; use cachepolicy=%s\n", p);
208 early_cachepolicy(p);
209 return 0;
210}
211early_param("nowb", early_nowrite);
212
213#ifndef CONFIG_ARM_LPAE
214static int __init early_ecc(char *p)
215{
216 if (memcmp(p, "on", 2) == 0)
217 ecc_mask = PMD_PROTECTION;
218 else if (memcmp(p, "off", 3) == 0)
219 ecc_mask = 0;
220 return 0;
221}
222early_param("ecc", early_ecc);
223#endif
224
225#else /* ifdef CONFIG_CPU_CP15 */
226
227static int __init early_cachepolicy(char *p)
228{
229 pr_warn("cachepolicy kernel parameter not supported without cp15\n");
230}
231early_param("cachepolicy", early_cachepolicy);
232
233static int __init noalign_setup(char *__unused)
234{
235 pr_warn("noalign kernel parameter not supported without cp15\n");
236}
237__setup("noalign", noalign_setup);
238
239#endif /* ifdef CONFIG_CPU_CP15 / else */
240
241#define PROT_PTE_DEVICE L_PTE_PRESENT|L_PTE_YOUNG|L_PTE_DIRTY|L_PTE_XN
242#define PROT_PTE_S2_DEVICE PROT_PTE_DEVICE
243#define PROT_SECT_DEVICE PMD_TYPE_SECT|PMD_SECT_AP_WRITE
244
245static struct mem_type mem_types[] __ro_after_init = {
246 [MT_DEVICE] = { /* Strongly ordered / ARMv6 shared device */
247 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_SHARED |
248 L_PTE_SHARED,
249 .prot_pte_s2 = s2_policy(PROT_PTE_S2_DEVICE) |
250 s2_policy(L_PTE_S2_MT_DEV_SHARED) |
251 L_PTE_SHARED,
252 .prot_l1 = PMD_TYPE_TABLE,
253 .prot_sect = PROT_SECT_DEVICE | PMD_SECT_S,
254 .domain = DOMAIN_IO,
255 },
256 [MT_DEVICE_NONSHARED] = { /* ARMv6 non-shared device */
257 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_NONSHARED,
258 .prot_l1 = PMD_TYPE_TABLE,
259 .prot_sect = PROT_SECT_DEVICE,
260 .domain = DOMAIN_IO,
261 },
262 [MT_DEVICE_CACHED] = { /* ioremap_cached */
263 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_CACHED,
264 .prot_l1 = PMD_TYPE_TABLE,
265 .prot_sect = PROT_SECT_DEVICE | PMD_SECT_WB,
266 .domain = DOMAIN_IO,
267 },
268 [MT_DEVICE_WC] = { /* ioremap_wc */
269 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_WC,
270 .prot_l1 = PMD_TYPE_TABLE,
271 .prot_sect = PROT_SECT_DEVICE,
272 .domain = DOMAIN_IO,
273 },
274 [MT_UNCACHED] = {
275 .prot_pte = PROT_PTE_DEVICE,
276 .prot_l1 = PMD_TYPE_TABLE,
277 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
278 .domain = DOMAIN_IO,
279 },
280 [MT_CACHECLEAN] = {
281 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
282 .domain = DOMAIN_KERNEL,
283 },
284#ifndef CONFIG_ARM_LPAE
285 [MT_MINICLEAN] = {
286 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN | PMD_SECT_MINICACHE,
287 .domain = DOMAIN_KERNEL,
288 },
289#endif
290 [MT_LOW_VECTORS] = {
291 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
292 L_PTE_RDONLY,
293 .prot_l1 = PMD_TYPE_TABLE,
294 .domain = DOMAIN_VECTORS,
295 },
296 [MT_HIGH_VECTORS] = {
297 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
298 L_PTE_USER | L_PTE_RDONLY,
299 .prot_l1 = PMD_TYPE_TABLE,
300 .domain = DOMAIN_VECTORS,
301 },
302 [MT_MEMORY_RWX] = {
303 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
304 .prot_l1 = PMD_TYPE_TABLE,
305 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
306 .domain = DOMAIN_KERNEL,
307 },
308 [MT_MEMORY_RW] = {
309 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
310 L_PTE_XN,
311 .prot_l1 = PMD_TYPE_TABLE,
312 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
313 .domain = DOMAIN_KERNEL,
314 },
315 [MT_ROM] = {
316 .prot_sect = PMD_TYPE_SECT,
317 .domain = DOMAIN_KERNEL,
318 },
319 [MT_MEMORY_RWX_NONCACHED] = {
320 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
321 L_PTE_MT_BUFFERABLE,
322 .prot_l1 = PMD_TYPE_TABLE,
323 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
324 .domain = DOMAIN_KERNEL,
325 },
326 [MT_MEMORY_RW_DTCM] = {
327 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
328 L_PTE_XN,
329 .prot_l1 = PMD_TYPE_TABLE,
330 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
331 .domain = DOMAIN_KERNEL,
332 },
333 [MT_MEMORY_RWX_ITCM] = {
334 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
335 .prot_l1 = PMD_TYPE_TABLE,
336 .domain = DOMAIN_KERNEL,
337 },
338 [MT_MEMORY_RW_SO] = {
339 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
340 L_PTE_MT_UNCACHED | L_PTE_XN,
341 .prot_l1 = PMD_TYPE_TABLE,
342 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_SECT_S |
343 PMD_SECT_UNCACHED | PMD_SECT_XN,
344 .domain = DOMAIN_KERNEL,
345 },
346 [MT_MEMORY_DMA_READY] = {
347 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
348 L_PTE_XN,
349 .prot_l1 = PMD_TYPE_TABLE,
350 .domain = DOMAIN_KERNEL,
351 },
352};
353
354const struct mem_type *get_mem_type(unsigned int type)
355{
356 return type < ARRAY_SIZE(mem_types) ? &mem_types[type] : NULL;
357}
358EXPORT_SYMBOL(get_mem_type);
359
360static pte_t *(*pte_offset_fixmap)(pmd_t *dir, unsigned long addr);
361
362static pte_t bm_pte[PTRS_PER_PTE + PTE_HWTABLE_PTRS]
363 __aligned(PTE_HWTABLE_OFF + PTE_HWTABLE_SIZE) __initdata;
364
365static pte_t * __init pte_offset_early_fixmap(pmd_t *dir, unsigned long addr)
366{
367 return &bm_pte[pte_index(addr)];
368}
369
370static pte_t *pte_offset_late_fixmap(pmd_t *dir, unsigned long addr)
371{
372 return pte_offset_kernel(dir, addr);
373}
374
375static inline pmd_t * __init fixmap_pmd(unsigned long addr)
376{
377 pgd_t *pgd = pgd_offset_k(addr);
378 pud_t *pud = pud_offset(pgd, addr);
379 pmd_t *pmd = pmd_offset(pud, addr);
380
381 return pmd;
382}
383
384void __init early_fixmap_init(void)
385{
386 pmd_t *pmd;
387
388 /*
389 * The early fixmap range spans multiple pmds, for which
390 * we are not prepared:
391 */
392 BUILD_BUG_ON((__fix_to_virt(__end_of_early_ioremap_region) >> PMD_SHIFT)
393 != FIXADDR_TOP >> PMD_SHIFT);
394
395 pmd = fixmap_pmd(FIXADDR_TOP);
396 pmd_populate_kernel(&init_mm, pmd, bm_pte);
397
398 pte_offset_fixmap = pte_offset_early_fixmap;
399}
400
401/*
402 * To avoid TLB flush broadcasts, this uses local_flush_tlb_kernel_range().
403 * As a result, this can only be called with preemption disabled, as under
404 * stop_machine().
405 */
406void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
407{
408 unsigned long vaddr = __fix_to_virt(idx);
409 pte_t *pte = pte_offset_fixmap(pmd_off_k(vaddr), vaddr);
410
411 /* Make sure fixmap region does not exceed available allocation. */
412 BUILD_BUG_ON(FIXADDR_START + (__end_of_fixed_addresses * PAGE_SIZE) >
413 FIXADDR_END);
414 BUG_ON(idx >= __end_of_fixed_addresses);
415
416 /* we only support device mappings until pgprot_kernel has been set */
417 if (WARN_ON(pgprot_val(prot) != pgprot_val(FIXMAP_PAGE_IO) &&
418 pgprot_val(pgprot_kernel) == 0))
419 return;
420
421 if (pgprot_val(prot))
422 set_pte_at(NULL, vaddr, pte,
423 pfn_pte(phys >> PAGE_SHIFT, prot));
424 else
425 pte_clear(NULL, vaddr, pte);
426 local_flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE);
427}
428
429/*
430 * Adjust the PMD section entries according to the CPU in use.
431 */
432static void __init build_mem_type_table(void)
433{
434 struct cachepolicy *cp;
435 unsigned int cr = get_cr();
436 pteval_t user_pgprot, kern_pgprot, vecs_pgprot;
437 pteval_t hyp_device_pgprot, s2_pgprot, s2_device_pgprot;
438 int cpu_arch = cpu_architecture();
439 int i;
440
441 if (cpu_arch < CPU_ARCH_ARMv6) {
442#if defined(CONFIG_CPU_DCACHE_DISABLE)
443 if (cachepolicy > CPOLICY_BUFFERED)
444 cachepolicy = CPOLICY_BUFFERED;
445#elif defined(CONFIG_CPU_DCACHE_WRITETHROUGH)
446 if (cachepolicy > CPOLICY_WRITETHROUGH)
447 cachepolicy = CPOLICY_WRITETHROUGH;
448#endif
449 }
450 if (cpu_arch < CPU_ARCH_ARMv5) {
451 if (cachepolicy >= CPOLICY_WRITEALLOC)
452 cachepolicy = CPOLICY_WRITEBACK;
453 ecc_mask = 0;
454 }
455
456 if (is_smp()) {
457 if (cachepolicy != CPOLICY_WRITEALLOC) {
458 pr_warn("Forcing write-allocate cache policy for SMP\n");
459 cachepolicy = CPOLICY_WRITEALLOC;
460 }
461 if (!(initial_pmd_value & PMD_SECT_S)) {
462 pr_warn("Forcing shared mappings for SMP\n");
463 initial_pmd_value |= PMD_SECT_S;
464 }
465 }
466
467 /*
468 * Strip out features not present on earlier architectures.
469 * Pre-ARMv5 CPUs don't have TEX bits. Pre-ARMv6 CPUs or those
470 * without extended page tables don't have the 'Shared' bit.
471 */
472 if (cpu_arch < CPU_ARCH_ARMv5)
473 for (i = 0; i < ARRAY_SIZE(mem_types); i++)
474 mem_types[i].prot_sect &= ~PMD_SECT_TEX(7);
475 if ((cpu_arch < CPU_ARCH_ARMv6 || !(cr & CR_XP)) && !cpu_is_xsc3())
476 for (i = 0; i < ARRAY_SIZE(mem_types); i++)
477 mem_types[i].prot_sect &= ~PMD_SECT_S;
478
479 /*
480 * ARMv5 and lower, bit 4 must be set for page tables (was: cache
481 * "update-able on write" bit on ARM610). However, Xscale and
482 * Xscale3 require this bit to be cleared.
483 */
484 if (cpu_is_xscale_family()) {
485 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
486 mem_types[i].prot_sect &= ~PMD_BIT4;
487 mem_types[i].prot_l1 &= ~PMD_BIT4;
488 }
489 } else if (cpu_arch < CPU_ARCH_ARMv6) {
490 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
491 if (mem_types[i].prot_l1)
492 mem_types[i].prot_l1 |= PMD_BIT4;
493 if (mem_types[i].prot_sect)
494 mem_types[i].prot_sect |= PMD_BIT4;
495 }
496 }
497
498 /*
499 * Mark the device areas according to the CPU/architecture.
500 */
501 if (cpu_is_xsc3() || (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP))) {
502 if (!cpu_is_xsc3()) {
503 /*
504 * Mark device regions on ARMv6+ as execute-never
505 * to prevent speculative instruction fetches.
506 */
507 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_XN;
508 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_XN;
509 mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_XN;
510 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_XN;
511
512 /* Also setup NX memory mapping */
513 mem_types[MT_MEMORY_RW].prot_sect |= PMD_SECT_XN;
514 }
515 if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
516 /*
517 * For ARMv7 with TEX remapping,
518 * - shared device is SXCB=1100
519 * - nonshared device is SXCB=0100
520 * - write combine device mem is SXCB=0001
521 * (Uncached Normal memory)
522 */
523 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_TEX(1);
524 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(1);
525 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_BUFFERABLE;
526 } else if (cpu_is_xsc3()) {
527 /*
528 * For Xscale3,
529 * - shared device is TEXCB=00101
530 * - nonshared device is TEXCB=01000
531 * - write combine device mem is TEXCB=00100
532 * (Inner/Outer Uncacheable in xsc3 parlance)
533 */
534 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_TEX(1) | PMD_SECT_BUFFERED;
535 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(2);
536 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1);
537 } else {
538 /*
539 * For ARMv6 and ARMv7 without TEX remapping,
540 * - shared device is TEXCB=00001
541 * - nonshared device is TEXCB=01000
542 * - write combine device mem is TEXCB=00100
543 * (Uncached Normal in ARMv6 parlance).
544 */
545 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_BUFFERED;
546 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(2);
547 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1);
548 }
549 } else {
550 /*
551 * On others, write combining is "Uncached/Buffered"
552 */
553 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_BUFFERABLE;
554 }
555
556 /*
557 * Now deal with the memory-type mappings
558 */
559 cp = &cache_policies[cachepolicy];
560 vecs_pgprot = kern_pgprot = user_pgprot = cp->pte;
561 s2_pgprot = cp->pte_s2;
562 hyp_device_pgprot = mem_types[MT_DEVICE].prot_pte;
563 s2_device_pgprot = mem_types[MT_DEVICE].prot_pte_s2;
564
565#ifndef CONFIG_ARM_LPAE
566 /*
567 * We don't use domains on ARMv6 (since this causes problems with
568 * v6/v7 kernels), so we must use a separate memory type for user
569 * r/o, kernel r/w to map the vectors page.
570 */
571 if (cpu_arch == CPU_ARCH_ARMv6)
572 vecs_pgprot |= L_PTE_MT_VECTORS;
573
574 /*
575 * Check is it with support for the PXN bit
576 * in the Short-descriptor translation table format descriptors.
577 */
578 if (cpu_arch == CPU_ARCH_ARMv7 &&
579 (read_cpuid_ext(CPUID_EXT_MMFR0) & 0xF) >= 4) {
580 user_pmd_table |= PMD_PXNTABLE;
581 }
582#endif
583
584 /*
585 * ARMv6 and above have extended page tables.
586 */
587 if (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP)) {
588#ifndef CONFIG_ARM_LPAE
589 /*
590 * Mark cache clean areas and XIP ROM read only
591 * from SVC mode and no access from userspace.
592 */
593 mem_types[MT_ROM].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
594 mem_types[MT_MINICLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
595 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
596#endif
597
598 /*
599 * If the initial page tables were created with the S bit
600 * set, then we need to do the same here for the same
601 * reasons given in early_cachepolicy().
602 */
603 if (initial_pmd_value & PMD_SECT_S) {
604 user_pgprot |= L_PTE_SHARED;
605 kern_pgprot |= L_PTE_SHARED;
606 vecs_pgprot |= L_PTE_SHARED;
607 s2_pgprot |= L_PTE_SHARED;
608 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_S;
609 mem_types[MT_DEVICE_WC].prot_pte |= L_PTE_SHARED;
610 mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_S;
611 mem_types[MT_DEVICE_CACHED].prot_pte |= L_PTE_SHARED;
612 mem_types[MT_MEMORY_RWX].prot_sect |= PMD_SECT_S;
613 mem_types[MT_MEMORY_RWX].prot_pte |= L_PTE_SHARED;
614 mem_types[MT_MEMORY_RW].prot_sect |= PMD_SECT_S;
615 mem_types[MT_MEMORY_RW].prot_pte |= L_PTE_SHARED;
616 mem_types[MT_MEMORY_DMA_READY].prot_pte |= L_PTE_SHARED;
617 mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |= PMD_SECT_S;
618 mem_types[MT_MEMORY_RWX_NONCACHED].prot_pte |= L_PTE_SHARED;
619 }
620 }
621
622 /*
623 * Non-cacheable Normal - intended for memory areas that must
624 * not cause dirty cache line writebacks when used
625 */
626 if (cpu_arch >= CPU_ARCH_ARMv6) {
627 if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
628 /* Non-cacheable Normal is XCB = 001 */
629 mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |=
630 PMD_SECT_BUFFERED;
631 } else {
632 /* For both ARMv6 and non-TEX-remapping ARMv7 */
633 mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |=
634 PMD_SECT_TEX(1);
635 }
636 } else {
637 mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |= PMD_SECT_BUFFERABLE;
638 }
639
640#ifdef CONFIG_ARM_LPAE
641 /*
642 * Do not generate access flag faults for the kernel mappings.
643 */
644 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
645 mem_types[i].prot_pte |= PTE_EXT_AF;
646 if (mem_types[i].prot_sect)
647 mem_types[i].prot_sect |= PMD_SECT_AF;
648 }
649 kern_pgprot |= PTE_EXT_AF;
650 vecs_pgprot |= PTE_EXT_AF;
651
652 /*
653 * Set PXN for user mappings
654 */
655 user_pgprot |= PTE_EXT_PXN;
656#endif
657
658 for (i = 0; i < 16; i++) {
659 pteval_t v = pgprot_val(protection_map[i]);
660 protection_map[i] = __pgprot(v | user_pgprot);
661 }
662
663 mem_types[MT_LOW_VECTORS].prot_pte |= vecs_pgprot;
664 mem_types[MT_HIGH_VECTORS].prot_pte |= vecs_pgprot;
665
666 pgprot_user = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | user_pgprot);
667 pgprot_kernel = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG |
668 L_PTE_DIRTY | kern_pgprot);
669 pgprot_s2 = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | s2_pgprot);
670 pgprot_s2_device = __pgprot(s2_device_pgprot);
671 pgprot_hyp_device = __pgprot(hyp_device_pgprot);
672
673 mem_types[MT_LOW_VECTORS].prot_l1 |= ecc_mask;
674 mem_types[MT_HIGH_VECTORS].prot_l1 |= ecc_mask;
675 mem_types[MT_MEMORY_RWX].prot_sect |= ecc_mask | cp->pmd;
676 mem_types[MT_MEMORY_RWX].prot_pte |= kern_pgprot;
677 mem_types[MT_MEMORY_RW].prot_sect |= ecc_mask | cp->pmd;
678 mem_types[MT_MEMORY_RW].prot_pte |= kern_pgprot;
679 mem_types[MT_MEMORY_DMA_READY].prot_pte |= kern_pgprot;
680 mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |= ecc_mask;
681 mem_types[MT_ROM].prot_sect |= cp->pmd;
682
683 switch (cp->pmd) {
684 case PMD_SECT_WT:
685 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WT;
686 break;
687 case PMD_SECT_WB:
688 case PMD_SECT_WBWA:
689 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WB;
690 break;
691 }
692 pr_info("Memory policy: %sData cache %s\n",
693 ecc_mask ? "ECC enabled, " : "", cp->policy);
694
695 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
696 struct mem_type *t = &mem_types[i];
697 if (t->prot_l1)
698 t->prot_l1 |= PMD_DOMAIN(t->domain);
699 if (t->prot_sect)
700 t->prot_sect |= PMD_DOMAIN(t->domain);
701 }
702}
703
704#ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
705pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
706 unsigned long size, pgprot_t vma_prot)
707{
708 if (!pfn_valid(pfn))
709 return pgprot_noncached(vma_prot);
710 else if (file->f_flags & O_SYNC)
711 return pgprot_writecombine(vma_prot);
712 return vma_prot;
713}
714EXPORT_SYMBOL(phys_mem_access_prot);
715#endif
716
717#define vectors_base() (vectors_high() ? 0xffff0000 : 0)
718
719static void __init *early_alloc(unsigned long sz)
720{
721 void *ptr = memblock_alloc(sz, sz);
722
723 if (!ptr)
724 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
725 __func__, sz, sz);
726
727 return ptr;
728}
729
730static void *__init late_alloc(unsigned long sz)
731{
732 void *ptr = (void *)__get_free_pages(GFP_PGTABLE_KERNEL, get_order(sz));
733
734 if (!ptr || !pgtable_pte_page_ctor(virt_to_page(ptr)))
735 BUG();
736 return ptr;
737}
738
739static pte_t * __init arm_pte_alloc(pmd_t *pmd, unsigned long addr,
740 unsigned long prot,
741 void *(*alloc)(unsigned long sz))
742{
743 if (pmd_none(*pmd)) {
744 pte_t *pte = alloc(PTE_HWTABLE_OFF + PTE_HWTABLE_SIZE);
745 __pmd_populate(pmd, __pa(pte), prot);
746 }
747 BUG_ON(pmd_bad(*pmd));
748 return pte_offset_kernel(pmd, addr);
749}
750
751static pte_t * __init early_pte_alloc(pmd_t *pmd, unsigned long addr,
752 unsigned long prot)
753{
754 return arm_pte_alloc(pmd, addr, prot, early_alloc);
755}
756
757static void __init alloc_init_pte(pmd_t *pmd, unsigned long addr,
758 unsigned long end, unsigned long pfn,
759 const struct mem_type *type,
760 void *(*alloc)(unsigned long sz),
761 bool ng)
762{
763 pte_t *pte = arm_pte_alloc(pmd, addr, type->prot_l1, alloc);
764 do {
765 set_pte_ext(pte, pfn_pte(pfn, __pgprot(type->prot_pte)),
766 ng ? PTE_EXT_NG : 0);
767 pfn++;
768 } while (pte++, addr += PAGE_SIZE, addr != end);
769}
770
771static void __init __map_init_section(pmd_t *pmd, unsigned long addr,
772 unsigned long end, phys_addr_t phys,
773 const struct mem_type *type, bool ng)
774{
775 pmd_t *p = pmd;
776
777#ifndef CONFIG_ARM_LPAE
778 /*
779 * In classic MMU format, puds and pmds are folded in to
780 * the pgds. pmd_offset gives the PGD entry. PGDs refer to a
781 * group of L1 entries making up one logical pointer to
782 * an L2 table (2MB), where as PMDs refer to the individual
783 * L1 entries (1MB). Hence increment to get the correct
784 * offset for odd 1MB sections.
785 * (See arch/arm/include/asm/pgtable-2level.h)
786 */
787 if (addr & SECTION_SIZE)
788 pmd++;
789#endif
790 do {
791 *pmd = __pmd(phys | type->prot_sect | (ng ? PMD_SECT_nG : 0));
792 phys += SECTION_SIZE;
793 } while (pmd++, addr += SECTION_SIZE, addr != end);
794
795 flush_pmd_entry(p);
796}
797
798static void __init alloc_init_pmd(pud_t *pud, unsigned long addr,
799 unsigned long end, phys_addr_t phys,
800 const struct mem_type *type,
801 void *(*alloc)(unsigned long sz), bool ng)
802{
803 pmd_t *pmd = pmd_offset(pud, addr);
804 unsigned long next;
805
806 do {
807 /*
808 * With LPAE, we must loop over to map
809 * all the pmds for the given range.
810 */
811 next = pmd_addr_end(addr, end);
812
813 /*
814 * Try a section mapping - addr, next and phys must all be
815 * aligned to a section boundary.
816 */
817 if (type->prot_sect &&
818 ((addr | next | phys) & ~SECTION_MASK) == 0) {
819 __map_init_section(pmd, addr, next, phys, type, ng);
820 } else {
821 alloc_init_pte(pmd, addr, next,
822 __phys_to_pfn(phys), type, alloc, ng);
823 }
824
825 phys += next - addr;
826
827 } while (pmd++, addr = next, addr != end);
828}
829
830static void __init alloc_init_pud(pgd_t *pgd, unsigned long addr,
831 unsigned long end, phys_addr_t phys,
832 const struct mem_type *type,
833 void *(*alloc)(unsigned long sz), bool ng)
834{
835 pud_t *pud = pud_offset(pgd, addr);
836 unsigned long next;
837
838 do {
839 next = pud_addr_end(addr, end);
840 alloc_init_pmd(pud, addr, next, phys, type, alloc, ng);
841 phys += next - addr;
842 } while (pud++, addr = next, addr != end);
843}
844
845#ifndef CONFIG_ARM_LPAE
846static void __init create_36bit_mapping(struct mm_struct *mm,
847 struct map_desc *md,
848 const struct mem_type *type,
849 bool ng)
850{
851 unsigned long addr, length, end;
852 phys_addr_t phys;
853 pgd_t *pgd;
854
855 addr = md->virtual;
856 phys = __pfn_to_phys(md->pfn);
857 length = PAGE_ALIGN(md->length);
858
859 if (!(cpu_architecture() >= CPU_ARCH_ARMv6 || cpu_is_xsc3())) {
860 pr_err("MM: CPU does not support supersection mapping for 0x%08llx at 0x%08lx\n",
861 (long long)__pfn_to_phys((u64)md->pfn), addr);
862 return;
863 }
864
865 /* N.B. ARMv6 supersections are only defined to work with domain 0.
866 * Since domain assignments can in fact be arbitrary, the
867 * 'domain == 0' check below is required to insure that ARMv6
868 * supersections are only allocated for domain 0 regardless
869 * of the actual domain assignments in use.
870 */
871 if (type->domain) {
872 pr_err("MM: invalid domain in supersection mapping for 0x%08llx at 0x%08lx\n",
873 (long long)__pfn_to_phys((u64)md->pfn), addr);
874 return;
875 }
876
877 if ((addr | length | __pfn_to_phys(md->pfn)) & ~SUPERSECTION_MASK) {
878 pr_err("MM: cannot create mapping for 0x%08llx at 0x%08lx invalid alignment\n",
879 (long long)__pfn_to_phys((u64)md->pfn), addr);
880 return;
881 }
882
883 /*
884 * Shift bits [35:32] of address into bits [23:20] of PMD
885 * (See ARMv6 spec).
886 */
887 phys |= (((md->pfn >> (32 - PAGE_SHIFT)) & 0xF) << 20);
888
889 pgd = pgd_offset(mm, addr);
890 end = addr + length;
891 do {
892 pud_t *pud = pud_offset(pgd, addr);
893 pmd_t *pmd = pmd_offset(pud, addr);
894 int i;
895
896 for (i = 0; i < 16; i++)
897 *pmd++ = __pmd(phys | type->prot_sect | PMD_SECT_SUPER |
898 (ng ? PMD_SECT_nG : 0));
899
900 addr += SUPERSECTION_SIZE;
901 phys += SUPERSECTION_SIZE;
902 pgd += SUPERSECTION_SIZE >> PGDIR_SHIFT;
903 } while (addr != end);
904}
905#endif /* !CONFIG_ARM_LPAE */
906
907static void __init __create_mapping(struct mm_struct *mm, struct map_desc *md,
908 void *(*alloc)(unsigned long sz),
909 bool ng)
910{
911 unsigned long addr, length, end;
912 phys_addr_t phys;
913 const struct mem_type *type;
914 pgd_t *pgd;
915
916 type = &mem_types[md->type];
917
918#ifndef CONFIG_ARM_LPAE
919 /*
920 * Catch 36-bit addresses
921 */
922 if (md->pfn >= 0x100000) {
923 create_36bit_mapping(mm, md, type, ng);
924 return;
925 }
926#endif
927
928 addr = md->virtual & PAGE_MASK;
929 phys = __pfn_to_phys(md->pfn);
930 length = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK));
931
932 if (type->prot_l1 == 0 && ((addr | phys | length) & ~SECTION_MASK)) {
933 pr_warn("BUG: map for 0x%08llx at 0x%08lx can not be mapped using pages, ignoring.\n",
934 (long long)__pfn_to_phys(md->pfn), addr);
935 return;
936 }
937
938 pgd = pgd_offset(mm, addr);
939 end = addr + length;
940 do {
941 unsigned long next = pgd_addr_end(addr, end);
942
943 alloc_init_pud(pgd, addr, next, phys, type, alloc, ng);
944
945 phys += next - addr;
946 addr = next;
947 } while (pgd++, addr != end);
948}
949
950/*
951 * Create the page directory entries and any necessary
952 * page tables for the mapping specified by `md'. We
953 * are able to cope here with varying sizes and address
954 * offsets, and we take full advantage of sections and
955 * supersections.
956 */
957static void __init create_mapping(struct map_desc *md)
958{
959 if (md->virtual != vectors_base() && md->virtual < TASK_SIZE) {
960 pr_warn("BUG: not creating mapping for 0x%08llx at 0x%08lx in user region\n",
961 (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
962 return;
963 }
964
965 if ((md->type == MT_DEVICE || md->type == MT_ROM) &&
966 md->virtual >= PAGE_OFFSET && md->virtual < FIXADDR_START &&
967 (md->virtual < VMALLOC_START || md->virtual >= VMALLOC_END)) {
968 pr_warn("BUG: mapping for 0x%08llx at 0x%08lx out of vmalloc space\n",
969 (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
970 }
971
972 __create_mapping(&init_mm, md, early_alloc, false);
973}
974
975void __init create_mapping_late(struct mm_struct *mm, struct map_desc *md,
976 bool ng)
977{
978#ifdef CONFIG_ARM_LPAE
979 pud_t *pud = pud_alloc(mm, pgd_offset(mm, md->virtual), md->virtual);
980 if (WARN_ON(!pud))
981 return;
982 pmd_alloc(mm, pud, 0);
983#endif
984 __create_mapping(mm, md, late_alloc, ng);
985}
986
987/*
988 * Create the architecture specific mappings
989 */
990void __init iotable_init(struct map_desc *io_desc, int nr)
991{
992 struct map_desc *md;
993 struct vm_struct *vm;
994 struct static_vm *svm;
995
996 if (!nr)
997 return;
998
999 svm = memblock_alloc(sizeof(*svm) * nr, __alignof__(*svm));
1000 if (!svm)
1001 panic("%s: Failed to allocate %zu bytes align=0x%zx\n",
1002 __func__, sizeof(*svm) * nr, __alignof__(*svm));
1003
1004 for (md = io_desc; nr; md++, nr--) {
1005 create_mapping(md);
1006
1007 vm = &svm->vm;
1008 vm->addr = (void *)(md->virtual & PAGE_MASK);
1009 vm->size = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK));
1010 vm->phys_addr = __pfn_to_phys(md->pfn);
1011 vm->flags = VM_IOREMAP | VM_ARM_STATIC_MAPPING;
1012 vm->flags |= VM_ARM_MTYPE(md->type);
1013 vm->caller = iotable_init;
1014 add_static_vm_early(svm++);
1015 }
1016}
1017
1018void __init vm_reserve_area_early(unsigned long addr, unsigned long size,
1019 void *caller)
1020{
1021 struct vm_struct *vm;
1022 struct static_vm *svm;
1023
1024 svm = memblock_alloc(sizeof(*svm), __alignof__(*svm));
1025 if (!svm)
1026 panic("%s: Failed to allocate %zu bytes align=0x%zx\n",
1027 __func__, sizeof(*svm), __alignof__(*svm));
1028
1029 vm = &svm->vm;
1030 vm->addr = (void *)addr;
1031 vm->size = size;
1032 vm->flags = VM_IOREMAP | VM_ARM_EMPTY_MAPPING;
1033 vm->caller = caller;
1034 add_static_vm_early(svm);
1035}
1036
1037#ifndef CONFIG_ARM_LPAE
1038
1039/*
1040 * The Linux PMD is made of two consecutive section entries covering 2MB
1041 * (see definition in include/asm/pgtable-2level.h). However a call to
1042 * create_mapping() may optimize static mappings by using individual
1043 * 1MB section mappings. This leaves the actual PMD potentially half
1044 * initialized if the top or bottom section entry isn't used, leaving it
1045 * open to problems if a subsequent ioremap() or vmalloc() tries to use
1046 * the virtual space left free by that unused section entry.
1047 *
1048 * Let's avoid the issue by inserting dummy vm entries covering the unused
1049 * PMD halves once the static mappings are in place.
1050 */
1051
1052static void __init pmd_empty_section_gap(unsigned long addr)
1053{
1054 vm_reserve_area_early(addr, SECTION_SIZE, pmd_empty_section_gap);
1055}
1056
1057static void __init fill_pmd_gaps(void)
1058{
1059 struct static_vm *svm;
1060 struct vm_struct *vm;
1061 unsigned long addr, next = 0;
1062 pmd_t *pmd;
1063
1064 list_for_each_entry(svm, &static_vmlist, list) {
1065 vm = &svm->vm;
1066 addr = (unsigned long)vm->addr;
1067 if (addr < next)
1068 continue;
1069
1070 /*
1071 * Check if this vm starts on an odd section boundary.
1072 * If so and the first section entry for this PMD is free
1073 * then we block the corresponding virtual address.
1074 */
1075 if ((addr & ~PMD_MASK) == SECTION_SIZE) {
1076 pmd = pmd_off_k(addr);
1077 if (pmd_none(*pmd))
1078 pmd_empty_section_gap(addr & PMD_MASK);
1079 }
1080
1081 /*
1082 * Then check if this vm ends on an odd section boundary.
1083 * If so and the second section entry for this PMD is empty
1084 * then we block the corresponding virtual address.
1085 */
1086 addr += vm->size;
1087 if ((addr & ~PMD_MASK) == SECTION_SIZE) {
1088 pmd = pmd_off_k(addr) + 1;
1089 if (pmd_none(*pmd))
1090 pmd_empty_section_gap(addr);
1091 }
1092
1093 /* no need to look at any vm entry until we hit the next PMD */
1094 next = (addr + PMD_SIZE - 1) & PMD_MASK;
1095 }
1096}
1097
1098#else
1099#define fill_pmd_gaps() do { } while (0)
1100#endif
1101
1102#if defined(CONFIG_PCI) && !defined(CONFIG_NEED_MACH_IO_H)
1103static void __init pci_reserve_io(void)
1104{
1105 struct static_vm *svm;
1106
1107 svm = find_static_vm_vaddr((void *)PCI_IO_VIRT_BASE);
1108 if (svm)
1109 return;
1110
1111 vm_reserve_area_early(PCI_IO_VIRT_BASE, SZ_2M, pci_reserve_io);
1112}
1113#else
1114#define pci_reserve_io() do { } while (0)
1115#endif
1116
1117#ifdef CONFIG_DEBUG_LL
1118void __init debug_ll_io_init(void)
1119{
1120 struct map_desc map;
1121
1122 debug_ll_addr(&map.pfn, &map.virtual);
1123 if (!map.pfn || !map.virtual)
1124 return;
1125 map.pfn = __phys_to_pfn(map.pfn);
1126 map.virtual &= PAGE_MASK;
1127 map.length = PAGE_SIZE;
1128 map.type = MT_DEVICE;
1129 iotable_init(&map, 1);
1130}
1131#endif
1132
1133static void * __initdata vmalloc_min =
1134 (void *)(VMALLOC_END - (240 << 20) - VMALLOC_OFFSET);
1135
1136/*
1137 * vmalloc=size forces the vmalloc area to be exactly 'size'
1138 * bytes. This can be used to increase (or decrease) the vmalloc
1139 * area - the default is 240m.
1140 */
1141static int __init early_vmalloc(char *arg)
1142{
1143 unsigned long vmalloc_reserve = memparse(arg, NULL);
1144
1145 if (vmalloc_reserve < SZ_16M) {
1146 vmalloc_reserve = SZ_16M;
1147 pr_warn("vmalloc area too small, limiting to %luMB\n",
1148 vmalloc_reserve >> 20);
1149 }
1150
1151 if (vmalloc_reserve > VMALLOC_END - (PAGE_OFFSET + SZ_32M)) {
1152 vmalloc_reserve = VMALLOC_END - (PAGE_OFFSET + SZ_32M);
1153 pr_warn("vmalloc area is too big, limiting to %luMB\n",
1154 vmalloc_reserve >> 20);
1155 }
1156
1157 vmalloc_min = (void *)(VMALLOC_END - vmalloc_reserve);
1158 return 0;
1159}
1160early_param("vmalloc", early_vmalloc);
1161
1162phys_addr_t arm_lowmem_limit __initdata = 0;
1163
1164void __init adjust_lowmem_bounds(void)
1165{
1166 phys_addr_t memblock_limit = 0;
1167 u64 vmalloc_limit;
1168 struct memblock_region *reg;
1169 phys_addr_t lowmem_limit = 0;
1170
1171 /*
1172 * Let's use our own (unoptimized) equivalent of __pa() that is
1173 * not affected by wrap-arounds when sizeof(phys_addr_t) == 4.
1174 * The result is used as the upper bound on physical memory address
1175 * and may itself be outside the valid range for which phys_addr_t
1176 * and therefore __pa() is defined.
1177 */
1178 vmalloc_limit = (u64)(uintptr_t)vmalloc_min - PAGE_OFFSET + PHYS_OFFSET;
1179
1180 /*
1181 * The first usable region must be PMD aligned. Mark its start
1182 * as MEMBLOCK_NOMAP if it isn't
1183 */
1184 for_each_memblock(memory, reg) {
1185 if (!memblock_is_nomap(reg)) {
1186 if (!IS_ALIGNED(reg->base, PMD_SIZE)) {
1187 phys_addr_t len;
1188
1189 len = round_up(reg->base, PMD_SIZE) - reg->base;
1190 memblock_mark_nomap(reg->base, len);
1191 }
1192 break;
1193 }
1194 }
1195
1196 for_each_memblock(memory, reg) {
1197 phys_addr_t block_start = reg->base;
1198 phys_addr_t block_end = reg->base + reg->size;
1199
1200 if (memblock_is_nomap(reg))
1201 continue;
1202
1203 if (reg->base < vmalloc_limit) {
1204 if (block_end > lowmem_limit)
1205 /*
1206 * Compare as u64 to ensure vmalloc_limit does
1207 * not get truncated. block_end should always
1208 * fit in phys_addr_t so there should be no
1209 * issue with assignment.
1210 */
1211 lowmem_limit = min_t(u64,
1212 vmalloc_limit,
1213 block_end);
1214
1215 /*
1216 * Find the first non-pmd-aligned page, and point
1217 * memblock_limit at it. This relies on rounding the
1218 * limit down to be pmd-aligned, which happens at the
1219 * end of this function.
1220 *
1221 * With this algorithm, the start or end of almost any
1222 * bank can be non-pmd-aligned. The only exception is
1223 * that the start of the bank 0 must be section-
1224 * aligned, since otherwise memory would need to be
1225 * allocated when mapping the start of bank 0, which
1226 * occurs before any free memory is mapped.
1227 */
1228 if (!memblock_limit) {
1229 if (!IS_ALIGNED(block_start, PMD_SIZE))
1230 memblock_limit = block_start;
1231 else if (!IS_ALIGNED(block_end, PMD_SIZE))
1232 memblock_limit = lowmem_limit;
1233 }
1234
1235 }
1236 }
1237
1238 arm_lowmem_limit = lowmem_limit;
1239
1240 high_memory = __va(arm_lowmem_limit - 1) + 1;
1241
1242 if (!memblock_limit)
1243 memblock_limit = arm_lowmem_limit;
1244
1245 /*
1246 * Round the memblock limit down to a pmd size. This
1247 * helps to ensure that we will allocate memory from the
1248 * last full pmd, which should be mapped.
1249 */
1250 memblock_limit = round_down(memblock_limit, PMD_SIZE);
1251
1252 if (!IS_ENABLED(CONFIG_HIGHMEM) || cache_is_vipt_aliasing()) {
1253 if (memblock_end_of_DRAM() > arm_lowmem_limit) {
1254 phys_addr_t end = memblock_end_of_DRAM();
1255
1256 pr_notice("Ignoring RAM at %pa-%pa\n",
1257 &memblock_limit, &end);
1258 pr_notice("Consider using a HIGHMEM enabled kernel.\n");
1259
1260 memblock_remove(memblock_limit, end - memblock_limit);
1261 }
1262 }
1263
1264 memblock_set_current_limit(memblock_limit);
1265}
1266
1267static inline void prepare_page_table(void)
1268{
1269 unsigned long addr;
1270 phys_addr_t end;
1271
1272 /*
1273 * Clear out all the mappings below the kernel image.
1274 */
1275 for (addr = 0; addr < MODULES_VADDR; addr += PMD_SIZE)
1276 pmd_clear(pmd_off_k(addr));
1277
1278#ifdef CONFIG_XIP_KERNEL
1279 /* The XIP kernel is mapped in the module area -- skip over it */
1280 addr = ((unsigned long)_exiprom + PMD_SIZE - 1) & PMD_MASK;
1281#endif
1282 for ( ; addr < PAGE_OFFSET; addr += PMD_SIZE)
1283 pmd_clear(pmd_off_k(addr));
1284
1285 /*
1286 * Find the end of the first block of lowmem.
1287 */
1288 end = memblock.memory.regions[0].base + memblock.memory.regions[0].size;
1289 if (end >= arm_lowmem_limit)
1290 end = arm_lowmem_limit;
1291
1292 /*
1293 * Clear out all the kernel space mappings, except for the first
1294 * memory bank, up to the vmalloc region.
1295 */
1296 for (addr = __phys_to_virt(end);
1297 addr < VMALLOC_START; addr += PMD_SIZE)
1298 pmd_clear(pmd_off_k(addr));
1299}
1300
1301#ifdef CONFIG_ARM_LPAE
1302/* the first page is reserved for pgd */
1303#define SWAPPER_PG_DIR_SIZE (PAGE_SIZE + \
1304 PTRS_PER_PGD * PTRS_PER_PMD * sizeof(pmd_t))
1305#else
1306#define SWAPPER_PG_DIR_SIZE (PTRS_PER_PGD * sizeof(pgd_t))
1307#endif
1308
1309/*
1310 * Reserve the special regions of memory
1311 */
1312void __init arm_mm_memblock_reserve(void)
1313{
1314 /*
1315 * Reserve the page tables. These are already in use,
1316 * and can only be in node 0.
1317 */
1318 memblock_reserve(__pa(swapper_pg_dir), SWAPPER_PG_DIR_SIZE);
1319
1320#ifdef CONFIG_SA1111
1321 /*
1322 * Because of the SA1111 DMA bug, we want to preserve our
1323 * precious DMA-able memory...
1324 */
1325 memblock_reserve(PHYS_OFFSET, __pa(swapper_pg_dir) - PHYS_OFFSET);
1326#endif
1327}
1328
1329/*
1330 * Set up the device mappings. Since we clear out the page tables for all
1331 * mappings above VMALLOC_START, except early fixmap, we might remove debug
1332 * device mappings. This means earlycon can be used to debug this function
1333 * Any other function or debugging method which may touch any device _will_
1334 * crash the kernel.
1335 */
1336static void __init devicemaps_init(const struct machine_desc *mdesc)
1337{
1338 struct map_desc map;
1339 unsigned long addr;
1340 void *vectors;
1341
1342 /*
1343 * Allocate the vector page early.
1344 */
1345 vectors = early_alloc(PAGE_SIZE * 2);
1346
1347 early_trap_init(vectors);
1348
1349 /*
1350 * Clear page table except top pmd used by early fixmaps
1351 */
1352 for (addr = VMALLOC_START; addr < (FIXADDR_TOP & PMD_MASK); addr += PMD_SIZE)
1353 pmd_clear(pmd_off_k(addr));
1354
1355 /*
1356 * Map the kernel if it is XIP.
1357 * It is always first in the modulearea.
1358 */
1359#ifdef CONFIG_XIP_KERNEL
1360 map.pfn = __phys_to_pfn(CONFIG_XIP_PHYS_ADDR & SECTION_MASK);
1361 map.virtual = MODULES_VADDR;
1362 map.length = ((unsigned long)_exiprom - map.virtual + ~SECTION_MASK) & SECTION_MASK;
1363 map.type = MT_ROM;
1364 create_mapping(&map);
1365#endif
1366
1367 /*
1368 * Map the cache flushing regions.
1369 */
1370#ifdef FLUSH_BASE
1371 map.pfn = __phys_to_pfn(FLUSH_BASE_PHYS);
1372 map.virtual = FLUSH_BASE;
1373 map.length = SZ_1M;
1374 map.type = MT_CACHECLEAN;
1375 create_mapping(&map);
1376#endif
1377#ifdef FLUSH_BASE_MINICACHE
1378 map.pfn = __phys_to_pfn(FLUSH_BASE_PHYS + SZ_1M);
1379 map.virtual = FLUSH_BASE_MINICACHE;
1380 map.length = SZ_1M;
1381 map.type = MT_MINICLEAN;
1382 create_mapping(&map);
1383#endif
1384
1385 /*
1386 * Create a mapping for the machine vectors at the high-vectors
1387 * location (0xffff0000). If we aren't using high-vectors, also
1388 * create a mapping at the low-vectors virtual address.
1389 */
1390 map.pfn = __phys_to_pfn(virt_to_phys(vectors));
1391 map.virtual = 0xffff0000;
1392 map.length = PAGE_SIZE;
1393#ifdef CONFIG_KUSER_HELPERS
1394 map.type = MT_HIGH_VECTORS;
1395#else
1396 map.type = MT_LOW_VECTORS;
1397#endif
1398 create_mapping(&map);
1399
1400 if (!vectors_high()) {
1401 map.virtual = 0;
1402 map.length = PAGE_SIZE * 2;
1403 map.type = MT_LOW_VECTORS;
1404 create_mapping(&map);
1405 }
1406
1407 /* Now create a kernel read-only mapping */
1408 map.pfn += 1;
1409 map.virtual = 0xffff0000 + PAGE_SIZE;
1410 map.length = PAGE_SIZE;
1411 map.type = MT_LOW_VECTORS;
1412 create_mapping(&map);
1413
1414 /*
1415 * Ask the machine support to map in the statically mapped devices.
1416 */
1417 if (mdesc->map_io)
1418 mdesc->map_io();
1419 else
1420 debug_ll_io_init();
1421 fill_pmd_gaps();
1422
1423 /* Reserve fixed i/o space in VMALLOC region */
1424 pci_reserve_io();
1425
1426 /*
1427 * Finally flush the caches and tlb to ensure that we're in a
1428 * consistent state wrt the writebuffer. This also ensures that
1429 * any write-allocated cache lines in the vector page are written
1430 * back. After this point, we can start to touch devices again.
1431 */
1432 local_flush_tlb_all();
1433 flush_cache_all();
1434
1435 /* Enable asynchronous aborts */
1436 early_abt_enable();
1437}
1438
1439static void __init kmap_init(void)
1440{
1441#ifdef CONFIG_HIGHMEM
1442 pkmap_page_table = early_pte_alloc(pmd_off_k(PKMAP_BASE),
1443 PKMAP_BASE, _PAGE_KERNEL_TABLE);
1444#endif
1445
1446 early_pte_alloc(pmd_off_k(FIXADDR_START), FIXADDR_START,
1447 _PAGE_KERNEL_TABLE);
1448}
1449
1450static void __init map_lowmem(void)
1451{
1452 struct memblock_region *reg;
1453 phys_addr_t kernel_x_start = round_down(__pa(KERNEL_START), SECTION_SIZE);
1454 phys_addr_t kernel_x_end = round_up(__pa(__init_end), SECTION_SIZE);
1455
1456 /* Map all the lowmem memory banks. */
1457 for_each_memblock(memory, reg) {
1458 phys_addr_t start = reg->base;
1459 phys_addr_t end = start + reg->size;
1460 struct map_desc map;
1461
1462 if (memblock_is_nomap(reg))
1463 continue;
1464
1465 if (end > arm_lowmem_limit)
1466 end = arm_lowmem_limit;
1467 if (start >= end)
1468 break;
1469
1470 if (end < kernel_x_start) {
1471 map.pfn = __phys_to_pfn(start);
1472 map.virtual = __phys_to_virt(start);
1473 map.length = end - start;
1474 map.type = MT_MEMORY_RWX;
1475
1476 create_mapping(&map);
1477 } else if (start >= kernel_x_end) {
1478 map.pfn = __phys_to_pfn(start);
1479 map.virtual = __phys_to_virt(start);
1480 map.length = end - start;
1481 map.type = MT_MEMORY_RW;
1482
1483 create_mapping(&map);
1484 } else {
1485 /* This better cover the entire kernel */
1486 if (start < kernel_x_start) {
1487 map.pfn = __phys_to_pfn(start);
1488 map.virtual = __phys_to_virt(start);
1489 map.length = kernel_x_start - start;
1490 map.type = MT_MEMORY_RW;
1491
1492 create_mapping(&map);
1493 }
1494
1495 map.pfn = __phys_to_pfn(kernel_x_start);
1496 map.virtual = __phys_to_virt(kernel_x_start);
1497 map.length = kernel_x_end - kernel_x_start;
1498 map.type = MT_MEMORY_RWX;
1499
1500 create_mapping(&map);
1501
1502 if (kernel_x_end < end) {
1503 map.pfn = __phys_to_pfn(kernel_x_end);
1504 map.virtual = __phys_to_virt(kernel_x_end);
1505 map.length = end - kernel_x_end;
1506 map.type = MT_MEMORY_RW;
1507
1508 create_mapping(&map);
1509 }
1510 }
1511 }
1512}
1513
1514#ifdef CONFIG_ARM_PV_FIXUP
1515extern unsigned long __atags_pointer;
1516typedef void pgtables_remap(long long offset, unsigned long pgd, void *bdata);
1517pgtables_remap lpae_pgtables_remap_asm;
1518
1519/*
1520 * early_paging_init() recreates boot time page table setup, allowing machines
1521 * to switch over to a high (>4G) address space on LPAE systems
1522 */
1523static void __init early_paging_init(const struct machine_desc *mdesc)
1524{
1525 pgtables_remap *lpae_pgtables_remap;
1526 unsigned long pa_pgd;
1527 unsigned int cr, ttbcr;
1528 long long offset;
1529 void *boot_data;
1530
1531 if (!mdesc->pv_fixup)
1532 return;
1533
1534 offset = mdesc->pv_fixup();
1535 if (offset == 0)
1536 return;
1537
1538 /*
1539 * Get the address of the remap function in the 1:1 identity
1540 * mapping setup by the early page table assembly code. We
1541 * must get this prior to the pv update. The following barrier
1542 * ensures that this is complete before we fixup any P:V offsets.
1543 */
1544 lpae_pgtables_remap = (pgtables_remap *)(unsigned long)__pa(lpae_pgtables_remap_asm);
1545 pa_pgd = __pa(swapper_pg_dir);
1546 boot_data = __va(__atags_pointer);
1547 barrier();
1548
1549 pr_info("Switching physical address space to 0x%08llx\n",
1550 (u64)PHYS_OFFSET + offset);
1551
1552 /* Re-set the phys pfn offset, and the pv offset */
1553 __pv_offset += offset;
1554 __pv_phys_pfn_offset += PFN_DOWN(offset);
1555
1556 /* Run the patch stub to update the constants */
1557 fixup_pv_table(&__pv_table_begin,
1558 (&__pv_table_end - &__pv_table_begin) << 2);
1559
1560 /*
1561 * We changing not only the virtual to physical mapping, but also
1562 * the physical addresses used to access memory. We need to flush
1563 * all levels of cache in the system with caching disabled to
1564 * ensure that all data is written back, and nothing is prefetched
1565 * into the caches. We also need to prevent the TLB walkers
1566 * allocating into the caches too. Note that this is ARMv7 LPAE
1567 * specific.
1568 */
1569 cr = get_cr();
1570 set_cr(cr & ~(CR_I | CR_C));
1571 asm("mrc p15, 0, %0, c2, c0, 2" : "=r" (ttbcr));
1572 asm volatile("mcr p15, 0, %0, c2, c0, 2"
1573 : : "r" (ttbcr & ~(3 << 8 | 3 << 10)));
1574 flush_cache_all();
1575
1576 /*
1577 * Fixup the page tables - this must be in the idmap region as
1578 * we need to disable the MMU to do this safely, and hence it
1579 * needs to be assembly. It's fairly simple, as we're using the
1580 * temporary tables setup by the initial assembly code.
1581 */
1582 lpae_pgtables_remap(offset, pa_pgd, boot_data);
1583
1584 /* Re-enable the caches and cacheable TLB walks */
1585 asm volatile("mcr p15, 0, %0, c2, c0, 2" : : "r" (ttbcr));
1586 set_cr(cr);
1587}
1588
1589#else
1590
1591static void __init early_paging_init(const struct machine_desc *mdesc)
1592{
1593 long long offset;
1594
1595 if (!mdesc->pv_fixup)
1596 return;
1597
1598 offset = mdesc->pv_fixup();
1599 if (offset == 0)
1600 return;
1601
1602 pr_crit("Physical address space modification is only to support Keystone2.\n");
1603 pr_crit("Please enable ARM_LPAE and ARM_PATCH_PHYS_VIRT support to use this\n");
1604 pr_crit("feature. Your kernel may crash now, have a good day.\n");
1605 add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
1606}
1607
1608#endif
1609
1610static void __init early_fixmap_shutdown(void)
1611{
1612 int i;
1613 unsigned long va = fix_to_virt(__end_of_permanent_fixed_addresses - 1);
1614
1615 pte_offset_fixmap = pte_offset_late_fixmap;
1616 pmd_clear(fixmap_pmd(va));
1617 local_flush_tlb_kernel_page(va);
1618
1619 for (i = 0; i < __end_of_permanent_fixed_addresses; i++) {
1620 pte_t *pte;
1621 struct map_desc map;
1622
1623 map.virtual = fix_to_virt(i);
1624 pte = pte_offset_early_fixmap(pmd_off_k(map.virtual), map.virtual);
1625
1626 /* Only i/o device mappings are supported ATM */
1627 if (pte_none(*pte) ||
1628 (pte_val(*pte) & L_PTE_MT_MASK) != L_PTE_MT_DEV_SHARED)
1629 continue;
1630
1631 map.pfn = pte_pfn(*pte);
1632 map.type = MT_DEVICE;
1633 map.length = PAGE_SIZE;
1634
1635 create_mapping(&map);
1636 }
1637}
1638
1639/*
1640 * paging_init() sets up the page tables, initialises the zone memory
1641 * maps, and sets up the zero page, bad page and bad page tables.
1642 */
1643void __init paging_init(const struct machine_desc *mdesc)
1644{
1645 void *zero_page;
1646
1647 prepare_page_table();
1648 map_lowmem();
1649 memblock_set_current_limit(arm_lowmem_limit);
1650 dma_contiguous_remap();
1651 early_fixmap_shutdown();
1652 devicemaps_init(mdesc);
1653 kmap_init();
1654 tcm_init();
1655
1656 top_pmd = pmd_off_k(0xffff0000);
1657
1658 /* allocate the zero page. */
1659 zero_page = early_alloc(PAGE_SIZE);
1660
1661 bootmem_init();
1662
1663 empty_zero_page = virt_to_page(zero_page);
1664 __flush_dcache_page(NULL, empty_zero_page);
1665
1666 /* Compute the virt/idmap offset, mostly for the sake of KVM */
1667 kimage_voffset = (unsigned long)&kimage_voffset - virt_to_idmap(&kimage_voffset);
1668}
1669
1670void __init early_mm_init(const struct machine_desc *mdesc)
1671{
1672 build_mem_type_table();
1673 early_paging_init(mdesc);
1674}