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Merge tag 'usb-3.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / arm / mm / mmu.c
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
20 #include <asm/cp15.h>
21 #include <asm/cputype.h>
22 #include <asm/sections.h>
23 #include <asm/cachetype.h>
24 #include <asm/setup.h>
25 #include <asm/sizes.h>
26 #include <asm/smp_plat.h>
27 #include <asm/tlb.h>
28 #include <asm/highmem.h>
29 #include <asm/system_info.h>
30 #include <asm/traps.h>
31
32 #include <asm/mach/arch.h>
33 #include <asm/mach/map.h>
34
35 #include "mm.h"
36
37 /*
38 * empty_zero_page is a special page that is used for
39 * zero-initialized data and COW.
40 */
41 struct page *empty_zero_page;
42 EXPORT_SYMBOL(empty_zero_page);
43
44 /*
45 * The pmd table for the upper-most set of pages.
46 */
47 pmd_t *top_pmd;
48
49 #define CPOLICY_UNCACHED 0
50 #define CPOLICY_BUFFERED 1
51 #define CPOLICY_WRITETHROUGH 2
52 #define CPOLICY_WRITEBACK 3
53 #define CPOLICY_WRITEALLOC 4
54
55 static unsigned int cachepolicy __initdata = CPOLICY_WRITEBACK;
56 static unsigned int ecc_mask __initdata = 0;
57 pgprot_t pgprot_user;
58 pgprot_t pgprot_kernel;
59
60 EXPORT_SYMBOL(pgprot_user);
61 EXPORT_SYMBOL(pgprot_kernel);
62
63 struct cachepolicy {
64 const char policy[16];
65 unsigned int cr_mask;
66 pmdval_t pmd;
67 pteval_t pte;
68 };
69
70 static struct cachepolicy cache_policies[] __initdata = {
71 {
72 .policy = "uncached",
73 .cr_mask = CR_W|CR_C,
74 .pmd = PMD_SECT_UNCACHED,
75 .pte = L_PTE_MT_UNCACHED,
76 }, {
77 .policy = "buffered",
78 .cr_mask = CR_C,
79 .pmd = PMD_SECT_BUFFERED,
80 .pte = L_PTE_MT_BUFFERABLE,
81 }, {
82 .policy = "writethrough",
83 .cr_mask = 0,
84 .pmd = PMD_SECT_WT,
85 .pte = L_PTE_MT_WRITETHROUGH,
86 }, {
87 .policy = "writeback",
88 .cr_mask = 0,
89 .pmd = PMD_SECT_WB,
90 .pte = L_PTE_MT_WRITEBACK,
91 }, {
92 .policy = "writealloc",
93 .cr_mask = 0,
94 .pmd = PMD_SECT_WBWA,
95 .pte = L_PTE_MT_WRITEALLOC,
96 }
97 };
98
99 /*
100 * These are useful for identifying cache coherency
101 * problems by allowing the cache or the cache and
102 * writebuffer to be turned off. (Note: the write
103 * buffer should not be on and the cache off).
104 */
105 static int __init early_cachepolicy(char *p)
106 {
107 int i;
108
109 for (i = 0; i < ARRAY_SIZE(cache_policies); i++) {
110 int len = strlen(cache_policies[i].policy);
111
112 if (memcmp(p, cache_policies[i].policy, len) == 0) {
113 cachepolicy = i;
114 cr_alignment &= ~cache_policies[i].cr_mask;
115 cr_no_alignment &= ~cache_policies[i].cr_mask;
116 break;
117 }
118 }
119 if (i == ARRAY_SIZE(cache_policies))
120 printk(KERN_ERR "ERROR: unknown or unsupported cache policy\n");
121 /*
122 * This restriction is partly to do with the way we boot; it is
123 * unpredictable to have memory mapped using two different sets of
124 * memory attributes (shared, type, and cache attribs). We can not
125 * change these attributes once the initial assembly has setup the
126 * page tables.
127 */
128 if (cpu_architecture() >= CPU_ARCH_ARMv6) {
129 printk(KERN_WARNING "Only cachepolicy=writeback supported on ARMv6 and later\n");
130 cachepolicy = CPOLICY_WRITEBACK;
131 }
132 flush_cache_all();
133 set_cr(cr_alignment);
134 return 0;
135 }
136 early_param("cachepolicy", early_cachepolicy);
137
138 static int __init early_nocache(char *__unused)
139 {
140 char *p = "buffered";
141 printk(KERN_WARNING "nocache is deprecated; use cachepolicy=%s\n", p);
142 early_cachepolicy(p);
143 return 0;
144 }
145 early_param("nocache", early_nocache);
146
147 static int __init early_nowrite(char *__unused)
148 {
149 char *p = "uncached";
150 printk(KERN_WARNING "nowb is deprecated; use cachepolicy=%s\n", p);
151 early_cachepolicy(p);
152 return 0;
153 }
154 early_param("nowb", early_nowrite);
155
156 #ifndef CONFIG_ARM_LPAE
157 static int __init early_ecc(char *p)
158 {
159 if (memcmp(p, "on", 2) == 0)
160 ecc_mask = PMD_PROTECTION;
161 else if (memcmp(p, "off", 3) == 0)
162 ecc_mask = 0;
163 return 0;
164 }
165 early_param("ecc", early_ecc);
166 #endif
167
168 static int __init noalign_setup(char *__unused)
169 {
170 cr_alignment &= ~CR_A;
171 cr_no_alignment &= ~CR_A;
172 set_cr(cr_alignment);
173 return 1;
174 }
175 __setup("noalign", noalign_setup);
176
177 #ifndef CONFIG_SMP
178 void adjust_cr(unsigned long mask, unsigned long set)
179 {
180 unsigned long flags;
181
182 mask &= ~CR_A;
183
184 set &= mask;
185
186 local_irq_save(flags);
187
188 cr_no_alignment = (cr_no_alignment & ~mask) | set;
189 cr_alignment = (cr_alignment & ~mask) | set;
190
191 set_cr((get_cr() & ~mask) | set);
192
193 local_irq_restore(flags);
194 }
195 #endif
196
197 #define PROT_PTE_DEVICE L_PTE_PRESENT|L_PTE_YOUNG|L_PTE_DIRTY|L_PTE_XN
198 #define PROT_SECT_DEVICE PMD_TYPE_SECT|PMD_SECT_AP_WRITE
199
200 static struct mem_type mem_types[] = {
201 [MT_DEVICE] = { /* Strongly ordered / ARMv6 shared device */
202 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_SHARED |
203 L_PTE_SHARED,
204 .prot_l1 = PMD_TYPE_TABLE,
205 .prot_sect = PROT_SECT_DEVICE | PMD_SECT_S,
206 .domain = DOMAIN_IO,
207 },
208 [MT_DEVICE_NONSHARED] = { /* ARMv6 non-shared device */
209 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_NONSHARED,
210 .prot_l1 = PMD_TYPE_TABLE,
211 .prot_sect = PROT_SECT_DEVICE,
212 .domain = DOMAIN_IO,
213 },
214 [MT_DEVICE_CACHED] = { /* ioremap_cached */
215 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_CACHED,
216 .prot_l1 = PMD_TYPE_TABLE,
217 .prot_sect = PROT_SECT_DEVICE | PMD_SECT_WB,
218 .domain = DOMAIN_IO,
219 },
220 [MT_DEVICE_WC] = { /* ioremap_wc */
221 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_WC,
222 .prot_l1 = PMD_TYPE_TABLE,
223 .prot_sect = PROT_SECT_DEVICE,
224 .domain = DOMAIN_IO,
225 },
226 [MT_UNCACHED] = {
227 .prot_pte = PROT_PTE_DEVICE,
228 .prot_l1 = PMD_TYPE_TABLE,
229 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
230 .domain = DOMAIN_IO,
231 },
232 [MT_CACHECLEAN] = {
233 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
234 .domain = DOMAIN_KERNEL,
235 },
236 #ifndef CONFIG_ARM_LPAE
237 [MT_MINICLEAN] = {
238 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN | PMD_SECT_MINICACHE,
239 .domain = DOMAIN_KERNEL,
240 },
241 #endif
242 [MT_LOW_VECTORS] = {
243 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
244 L_PTE_RDONLY,
245 .prot_l1 = PMD_TYPE_TABLE,
246 .domain = DOMAIN_USER,
247 },
248 [MT_HIGH_VECTORS] = {
249 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
250 L_PTE_USER | L_PTE_RDONLY,
251 .prot_l1 = PMD_TYPE_TABLE,
252 .domain = DOMAIN_USER,
253 },
254 [MT_MEMORY] = {
255 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
256 .prot_l1 = PMD_TYPE_TABLE,
257 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
258 .domain = DOMAIN_KERNEL,
259 },
260 [MT_ROM] = {
261 .prot_sect = PMD_TYPE_SECT,
262 .domain = DOMAIN_KERNEL,
263 },
264 [MT_MEMORY_NONCACHED] = {
265 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
266 L_PTE_MT_BUFFERABLE,
267 .prot_l1 = PMD_TYPE_TABLE,
268 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
269 .domain = DOMAIN_KERNEL,
270 },
271 [MT_MEMORY_DTCM] = {
272 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
273 L_PTE_XN,
274 .prot_l1 = PMD_TYPE_TABLE,
275 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
276 .domain = DOMAIN_KERNEL,
277 },
278 [MT_MEMORY_ITCM] = {
279 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
280 .prot_l1 = PMD_TYPE_TABLE,
281 .domain = DOMAIN_KERNEL,
282 },
283 [MT_MEMORY_SO] = {
284 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
285 L_PTE_MT_UNCACHED,
286 .prot_l1 = PMD_TYPE_TABLE,
287 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_SECT_S |
288 PMD_SECT_UNCACHED | PMD_SECT_XN,
289 .domain = DOMAIN_KERNEL,
290 },
291 [MT_MEMORY_DMA_READY] = {
292 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
293 .prot_l1 = PMD_TYPE_TABLE,
294 .domain = DOMAIN_KERNEL,
295 },
296 };
297
298 const struct mem_type *get_mem_type(unsigned int type)
299 {
300 return type < ARRAY_SIZE(mem_types) ? &mem_types[type] : NULL;
301 }
302 EXPORT_SYMBOL(get_mem_type);
303
304 /*
305 * Adjust the PMD section entries according to the CPU in use.
306 */
307 static void __init build_mem_type_table(void)
308 {
309 struct cachepolicy *cp;
310 unsigned int cr = get_cr();
311 pteval_t user_pgprot, kern_pgprot, vecs_pgprot;
312 int cpu_arch = cpu_architecture();
313 int i;
314
315 if (cpu_arch < CPU_ARCH_ARMv6) {
316 #if defined(CONFIG_CPU_DCACHE_DISABLE)
317 if (cachepolicy > CPOLICY_BUFFERED)
318 cachepolicy = CPOLICY_BUFFERED;
319 #elif defined(CONFIG_CPU_DCACHE_WRITETHROUGH)
320 if (cachepolicy > CPOLICY_WRITETHROUGH)
321 cachepolicy = CPOLICY_WRITETHROUGH;
322 #endif
323 }
324 if (cpu_arch < CPU_ARCH_ARMv5) {
325 if (cachepolicy >= CPOLICY_WRITEALLOC)
326 cachepolicy = CPOLICY_WRITEBACK;
327 ecc_mask = 0;
328 }
329 if (is_smp())
330 cachepolicy = CPOLICY_WRITEALLOC;
331
332 /*
333 * Strip out features not present on earlier architectures.
334 * Pre-ARMv5 CPUs don't have TEX bits. Pre-ARMv6 CPUs or those
335 * without extended page tables don't have the 'Shared' bit.
336 */
337 if (cpu_arch < CPU_ARCH_ARMv5)
338 for (i = 0; i < ARRAY_SIZE(mem_types); i++)
339 mem_types[i].prot_sect &= ~PMD_SECT_TEX(7);
340 if ((cpu_arch < CPU_ARCH_ARMv6 || !(cr & CR_XP)) && !cpu_is_xsc3())
341 for (i = 0; i < ARRAY_SIZE(mem_types); i++)
342 mem_types[i].prot_sect &= ~PMD_SECT_S;
343
344 /*
345 * ARMv5 and lower, bit 4 must be set for page tables (was: cache
346 * "update-able on write" bit on ARM610). However, Xscale and
347 * Xscale3 require this bit to be cleared.
348 */
349 if (cpu_is_xscale() || cpu_is_xsc3()) {
350 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
351 mem_types[i].prot_sect &= ~PMD_BIT4;
352 mem_types[i].prot_l1 &= ~PMD_BIT4;
353 }
354 } else if (cpu_arch < CPU_ARCH_ARMv6) {
355 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
356 if (mem_types[i].prot_l1)
357 mem_types[i].prot_l1 |= PMD_BIT4;
358 if (mem_types[i].prot_sect)
359 mem_types[i].prot_sect |= PMD_BIT4;
360 }
361 }
362
363 /*
364 * Mark the device areas according to the CPU/architecture.
365 */
366 if (cpu_is_xsc3() || (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP))) {
367 if (!cpu_is_xsc3()) {
368 /*
369 * Mark device regions on ARMv6+ as execute-never
370 * to prevent speculative instruction fetches.
371 */
372 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_XN;
373 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_XN;
374 mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_XN;
375 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_XN;
376 }
377 if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
378 /*
379 * For ARMv7 with TEX remapping,
380 * - shared device is SXCB=1100
381 * - nonshared device is SXCB=0100
382 * - write combine device mem is SXCB=0001
383 * (Uncached Normal memory)
384 */
385 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_TEX(1);
386 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(1);
387 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_BUFFERABLE;
388 } else if (cpu_is_xsc3()) {
389 /*
390 * For Xscale3,
391 * - shared device is TEXCB=00101
392 * - nonshared device is TEXCB=01000
393 * - write combine device mem is TEXCB=00100
394 * (Inner/Outer Uncacheable in xsc3 parlance)
395 */
396 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_TEX(1) | PMD_SECT_BUFFERED;
397 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(2);
398 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1);
399 } else {
400 /*
401 * For ARMv6 and ARMv7 without TEX remapping,
402 * - shared device is TEXCB=00001
403 * - nonshared device is TEXCB=01000
404 * - write combine device mem is TEXCB=00100
405 * (Uncached Normal in ARMv6 parlance).
406 */
407 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_BUFFERED;
408 mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(2);
409 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1);
410 }
411 } else {
412 /*
413 * On others, write combining is "Uncached/Buffered"
414 */
415 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_BUFFERABLE;
416 }
417
418 /*
419 * Now deal with the memory-type mappings
420 */
421 cp = &cache_policies[cachepolicy];
422 vecs_pgprot = kern_pgprot = user_pgprot = cp->pte;
423
424 /*
425 * Only use write-through for non-SMP systems
426 */
427 if (!is_smp() && cpu_arch >= CPU_ARCH_ARMv5 && cachepolicy > CPOLICY_WRITETHROUGH)
428 vecs_pgprot = cache_policies[CPOLICY_WRITETHROUGH].pte;
429
430 /*
431 * Enable CPU-specific coherency if supported.
432 * (Only available on XSC3 at the moment.)
433 */
434 if (arch_is_coherent() && cpu_is_xsc3()) {
435 mem_types[MT_MEMORY].prot_sect |= PMD_SECT_S;
436 mem_types[MT_MEMORY].prot_pte |= L_PTE_SHARED;
437 mem_types[MT_MEMORY_DMA_READY].prot_pte |= L_PTE_SHARED;
438 mem_types[MT_MEMORY_NONCACHED].prot_sect |= PMD_SECT_S;
439 mem_types[MT_MEMORY_NONCACHED].prot_pte |= L_PTE_SHARED;
440 }
441 /*
442 * ARMv6 and above have extended page tables.
443 */
444 if (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP)) {
445 #ifndef CONFIG_ARM_LPAE
446 /*
447 * Mark cache clean areas and XIP ROM read only
448 * from SVC mode and no access from userspace.
449 */
450 mem_types[MT_ROM].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
451 mem_types[MT_MINICLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
452 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
453 #endif
454
455 if (is_smp()) {
456 /*
457 * Mark memory with the "shared" attribute
458 * for SMP systems
459 */
460 user_pgprot |= L_PTE_SHARED;
461 kern_pgprot |= L_PTE_SHARED;
462 vecs_pgprot |= L_PTE_SHARED;
463 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_S;
464 mem_types[MT_DEVICE_WC].prot_pte |= L_PTE_SHARED;
465 mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_S;
466 mem_types[MT_DEVICE_CACHED].prot_pte |= L_PTE_SHARED;
467 mem_types[MT_MEMORY].prot_sect |= PMD_SECT_S;
468 mem_types[MT_MEMORY].prot_pte |= L_PTE_SHARED;
469 mem_types[MT_MEMORY_DMA_READY].prot_pte |= L_PTE_SHARED;
470 mem_types[MT_MEMORY_NONCACHED].prot_sect |= PMD_SECT_S;
471 mem_types[MT_MEMORY_NONCACHED].prot_pte |= L_PTE_SHARED;
472 }
473 }
474
475 /*
476 * Non-cacheable Normal - intended for memory areas that must
477 * not cause dirty cache line writebacks when used
478 */
479 if (cpu_arch >= CPU_ARCH_ARMv6) {
480 if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
481 /* Non-cacheable Normal is XCB = 001 */
482 mem_types[MT_MEMORY_NONCACHED].prot_sect |=
483 PMD_SECT_BUFFERED;
484 } else {
485 /* For both ARMv6 and non-TEX-remapping ARMv7 */
486 mem_types[MT_MEMORY_NONCACHED].prot_sect |=
487 PMD_SECT_TEX(1);
488 }
489 } else {
490 mem_types[MT_MEMORY_NONCACHED].prot_sect |= PMD_SECT_BUFFERABLE;
491 }
492
493 #ifdef CONFIG_ARM_LPAE
494 /*
495 * Do not generate access flag faults for the kernel mappings.
496 */
497 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
498 mem_types[i].prot_pte |= PTE_EXT_AF;
499 if (mem_types[i].prot_sect)
500 mem_types[i].prot_sect |= PMD_SECT_AF;
501 }
502 kern_pgprot |= PTE_EXT_AF;
503 vecs_pgprot |= PTE_EXT_AF;
504 #endif
505
506 for (i = 0; i < 16; i++) {
507 unsigned long v = pgprot_val(protection_map[i]);
508 protection_map[i] = __pgprot(v | user_pgprot);
509 }
510
511 mem_types[MT_LOW_VECTORS].prot_pte |= vecs_pgprot;
512 mem_types[MT_HIGH_VECTORS].prot_pte |= vecs_pgprot;
513
514 pgprot_user = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | user_pgprot);
515 pgprot_kernel = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG |
516 L_PTE_DIRTY | kern_pgprot);
517
518 mem_types[MT_LOW_VECTORS].prot_l1 |= ecc_mask;
519 mem_types[MT_HIGH_VECTORS].prot_l1 |= ecc_mask;
520 mem_types[MT_MEMORY].prot_sect |= ecc_mask | cp->pmd;
521 mem_types[MT_MEMORY].prot_pte |= kern_pgprot;
522 mem_types[MT_MEMORY_DMA_READY].prot_pte |= kern_pgprot;
523 mem_types[MT_MEMORY_NONCACHED].prot_sect |= ecc_mask;
524 mem_types[MT_ROM].prot_sect |= cp->pmd;
525
526 switch (cp->pmd) {
527 case PMD_SECT_WT:
528 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WT;
529 break;
530 case PMD_SECT_WB:
531 case PMD_SECT_WBWA:
532 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WB;
533 break;
534 }
535 printk("Memory policy: ECC %sabled, Data cache %s\n",
536 ecc_mask ? "en" : "dis", cp->policy);
537
538 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
539 struct mem_type *t = &mem_types[i];
540 if (t->prot_l1)
541 t->prot_l1 |= PMD_DOMAIN(t->domain);
542 if (t->prot_sect)
543 t->prot_sect |= PMD_DOMAIN(t->domain);
544 }
545 }
546
547 #ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
548 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
549 unsigned long size, pgprot_t vma_prot)
550 {
551 if (!pfn_valid(pfn))
552 return pgprot_noncached(vma_prot);
553 else if (file->f_flags & O_SYNC)
554 return pgprot_writecombine(vma_prot);
555 return vma_prot;
556 }
557 EXPORT_SYMBOL(phys_mem_access_prot);
558 #endif
559
560 #define vectors_base() (vectors_high() ? 0xffff0000 : 0)
561
562 static void __init *early_alloc_aligned(unsigned long sz, unsigned long align)
563 {
564 void *ptr = __va(memblock_alloc(sz, align));
565 memset(ptr, 0, sz);
566 return ptr;
567 }
568
569 static void __init *early_alloc(unsigned long sz)
570 {
571 return early_alloc_aligned(sz, sz);
572 }
573
574 static pte_t * __init early_pte_alloc(pmd_t *pmd, unsigned long addr, unsigned long prot)
575 {
576 if (pmd_none(*pmd)) {
577 pte_t *pte = early_alloc(PTE_HWTABLE_OFF + PTE_HWTABLE_SIZE);
578 __pmd_populate(pmd, __pa(pte), prot);
579 }
580 BUG_ON(pmd_bad(*pmd));
581 return pte_offset_kernel(pmd, addr);
582 }
583
584 static void __init alloc_init_pte(pmd_t *pmd, unsigned long addr,
585 unsigned long end, unsigned long pfn,
586 const struct mem_type *type)
587 {
588 pte_t *pte = early_pte_alloc(pmd, addr, type->prot_l1);
589 do {
590 set_pte_ext(pte, pfn_pte(pfn, __pgprot(type->prot_pte)), 0);
591 pfn++;
592 } while (pte++, addr += PAGE_SIZE, addr != end);
593 }
594
595 static void __init alloc_init_section(pud_t *pud, unsigned long addr,
596 unsigned long end, phys_addr_t phys,
597 const struct mem_type *type)
598 {
599 pmd_t *pmd = pmd_offset(pud, addr);
600
601 /*
602 * Try a section mapping - end, addr and phys must all be aligned
603 * to a section boundary. Note that PMDs refer to the individual
604 * L1 entries, whereas PGDs refer to a group of L1 entries making
605 * up one logical pointer to an L2 table.
606 */
607 if (type->prot_sect && ((addr | end | phys) & ~SECTION_MASK) == 0) {
608 pmd_t *p = pmd;
609
610 #ifndef CONFIG_ARM_LPAE
611 if (addr & SECTION_SIZE)
612 pmd++;
613 #endif
614
615 do {
616 *pmd = __pmd(phys | type->prot_sect);
617 phys += SECTION_SIZE;
618 } while (pmd++, addr += SECTION_SIZE, addr != end);
619
620 flush_pmd_entry(p);
621 } else {
622 /*
623 * No need to loop; pte's aren't interested in the
624 * individual L1 entries.
625 */
626 alloc_init_pte(pmd, addr, end, __phys_to_pfn(phys), type);
627 }
628 }
629
630 static void __init alloc_init_pud(pgd_t *pgd, unsigned long addr,
631 unsigned long end, unsigned long phys, const struct mem_type *type)
632 {
633 pud_t *pud = pud_offset(pgd, addr);
634 unsigned long next;
635
636 do {
637 next = pud_addr_end(addr, end);
638 alloc_init_section(pud, addr, next, phys, type);
639 phys += next - addr;
640 } while (pud++, addr = next, addr != end);
641 }
642
643 #ifndef CONFIG_ARM_LPAE
644 static void __init create_36bit_mapping(struct map_desc *md,
645 const struct mem_type *type)
646 {
647 unsigned long addr, length, end;
648 phys_addr_t phys;
649 pgd_t *pgd;
650
651 addr = md->virtual;
652 phys = __pfn_to_phys(md->pfn);
653 length = PAGE_ALIGN(md->length);
654
655 if (!(cpu_architecture() >= CPU_ARCH_ARMv6 || cpu_is_xsc3())) {
656 printk(KERN_ERR "MM: CPU does not support supersection "
657 "mapping for 0x%08llx at 0x%08lx\n",
658 (long long)__pfn_to_phys((u64)md->pfn), addr);
659 return;
660 }
661
662 /* N.B. ARMv6 supersections are only defined to work with domain 0.
663 * Since domain assignments can in fact be arbitrary, the
664 * 'domain == 0' check below is required to insure that ARMv6
665 * supersections are only allocated for domain 0 regardless
666 * of the actual domain assignments in use.
667 */
668 if (type->domain) {
669 printk(KERN_ERR "MM: invalid domain in supersection "
670 "mapping for 0x%08llx at 0x%08lx\n",
671 (long long)__pfn_to_phys((u64)md->pfn), addr);
672 return;
673 }
674
675 if ((addr | length | __pfn_to_phys(md->pfn)) & ~SUPERSECTION_MASK) {
676 printk(KERN_ERR "MM: cannot create mapping for 0x%08llx"
677 " at 0x%08lx invalid alignment\n",
678 (long long)__pfn_to_phys((u64)md->pfn), addr);
679 return;
680 }
681
682 /*
683 * Shift bits [35:32] of address into bits [23:20] of PMD
684 * (See ARMv6 spec).
685 */
686 phys |= (((md->pfn >> (32 - PAGE_SHIFT)) & 0xF) << 20);
687
688 pgd = pgd_offset_k(addr);
689 end = addr + length;
690 do {
691 pud_t *pud = pud_offset(pgd, addr);
692 pmd_t *pmd = pmd_offset(pud, addr);
693 int i;
694
695 for (i = 0; i < 16; i++)
696 *pmd++ = __pmd(phys | type->prot_sect | PMD_SECT_SUPER);
697
698 addr += SUPERSECTION_SIZE;
699 phys += SUPERSECTION_SIZE;
700 pgd += SUPERSECTION_SIZE >> PGDIR_SHIFT;
701 } while (addr != end);
702 }
703 #endif /* !CONFIG_ARM_LPAE */
704
705 /*
706 * Create the page directory entries and any necessary
707 * page tables for the mapping specified by `md'. We
708 * are able to cope here with varying sizes and address
709 * offsets, and we take full advantage of sections and
710 * supersections.
711 */
712 static void __init create_mapping(struct map_desc *md)
713 {
714 unsigned long addr, length, end;
715 phys_addr_t phys;
716 const struct mem_type *type;
717 pgd_t *pgd;
718
719 if (md->virtual != vectors_base() && md->virtual < TASK_SIZE) {
720 printk(KERN_WARNING "BUG: not creating mapping for 0x%08llx"
721 " at 0x%08lx in user region\n",
722 (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
723 return;
724 }
725
726 if ((md->type == MT_DEVICE || md->type == MT_ROM) &&
727 md->virtual >= PAGE_OFFSET &&
728 (md->virtual < VMALLOC_START || md->virtual >= VMALLOC_END)) {
729 printk(KERN_WARNING "BUG: mapping for 0x%08llx"
730 " at 0x%08lx out of vmalloc space\n",
731 (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
732 }
733
734 type = &mem_types[md->type];
735
736 #ifndef CONFIG_ARM_LPAE
737 /*
738 * Catch 36-bit addresses
739 */
740 if (md->pfn >= 0x100000) {
741 create_36bit_mapping(md, type);
742 return;
743 }
744 #endif
745
746 addr = md->virtual & PAGE_MASK;
747 phys = __pfn_to_phys(md->pfn);
748 length = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK));
749
750 if (type->prot_l1 == 0 && ((addr | phys | length) & ~SECTION_MASK)) {
751 printk(KERN_WARNING "BUG: map for 0x%08llx at 0x%08lx can not "
752 "be mapped using pages, ignoring.\n",
753 (long long)__pfn_to_phys(md->pfn), addr);
754 return;
755 }
756
757 pgd = pgd_offset_k(addr);
758 end = addr + length;
759 do {
760 unsigned long next = pgd_addr_end(addr, end);
761
762 alloc_init_pud(pgd, addr, next, phys, type);
763
764 phys += next - addr;
765 addr = next;
766 } while (pgd++, addr != end);
767 }
768
769 /*
770 * Create the architecture specific mappings
771 */
772 void __init iotable_init(struct map_desc *io_desc, int nr)
773 {
774 struct map_desc *md;
775 struct vm_struct *vm;
776
777 if (!nr)
778 return;
779
780 vm = early_alloc_aligned(sizeof(*vm) * nr, __alignof__(*vm));
781
782 for (md = io_desc; nr; md++, nr--) {
783 create_mapping(md);
784 vm->addr = (void *)(md->virtual & PAGE_MASK);
785 vm->size = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK));
786 vm->phys_addr = __pfn_to_phys(md->pfn);
787 vm->flags = VM_IOREMAP | VM_ARM_STATIC_MAPPING;
788 vm->flags |= VM_ARM_MTYPE(md->type);
789 vm->caller = iotable_init;
790 vm_area_add_early(vm++);
791 }
792 }
793
794 #ifndef CONFIG_ARM_LPAE
795
796 /*
797 * The Linux PMD is made of two consecutive section entries covering 2MB
798 * (see definition in include/asm/pgtable-2level.h). However a call to
799 * create_mapping() may optimize static mappings by using individual
800 * 1MB section mappings. This leaves the actual PMD potentially half
801 * initialized if the top or bottom section entry isn't used, leaving it
802 * open to problems if a subsequent ioremap() or vmalloc() tries to use
803 * the virtual space left free by that unused section entry.
804 *
805 * Let's avoid the issue by inserting dummy vm entries covering the unused
806 * PMD halves once the static mappings are in place.
807 */
808
809 static void __init pmd_empty_section_gap(unsigned long addr)
810 {
811 struct vm_struct *vm;
812
813 vm = early_alloc_aligned(sizeof(*vm), __alignof__(*vm));
814 vm->addr = (void *)addr;
815 vm->size = SECTION_SIZE;
816 vm->flags = VM_IOREMAP | VM_ARM_STATIC_MAPPING;
817 vm->caller = pmd_empty_section_gap;
818 vm_area_add_early(vm);
819 }
820
821 static void __init fill_pmd_gaps(void)
822 {
823 struct vm_struct *vm;
824 unsigned long addr, next = 0;
825 pmd_t *pmd;
826
827 /* we're still single threaded hence no lock needed here */
828 for (vm = vmlist; vm; vm = vm->next) {
829 if (!(vm->flags & VM_ARM_STATIC_MAPPING))
830 continue;
831 addr = (unsigned long)vm->addr;
832 if (addr < next)
833 continue;
834
835 /*
836 * Check if this vm starts on an odd section boundary.
837 * If so and the first section entry for this PMD is free
838 * then we block the corresponding virtual address.
839 */
840 if ((addr & ~PMD_MASK) == SECTION_SIZE) {
841 pmd = pmd_off_k(addr);
842 if (pmd_none(*pmd))
843 pmd_empty_section_gap(addr & PMD_MASK);
844 }
845
846 /*
847 * Then check if this vm ends on an odd section boundary.
848 * If so and the second section entry for this PMD is empty
849 * then we block the corresponding virtual address.
850 */
851 addr += vm->size;
852 if ((addr & ~PMD_MASK) == SECTION_SIZE) {
853 pmd = pmd_off_k(addr) + 1;
854 if (pmd_none(*pmd))
855 pmd_empty_section_gap(addr);
856 }
857
858 /* no need to look at any vm entry until we hit the next PMD */
859 next = (addr + PMD_SIZE - 1) & PMD_MASK;
860 }
861 }
862
863 #else
864 #define fill_pmd_gaps() do { } while (0)
865 #endif
866
867 static void * __initdata vmalloc_min =
868 (void *)(VMALLOC_END - (240 << 20) - VMALLOC_OFFSET);
869
870 /*
871 * vmalloc=size forces the vmalloc area to be exactly 'size'
872 * bytes. This can be used to increase (or decrease) the vmalloc
873 * area - the default is 240m.
874 */
875 static int __init early_vmalloc(char *arg)
876 {
877 unsigned long vmalloc_reserve = memparse(arg, NULL);
878
879 if (vmalloc_reserve < SZ_16M) {
880 vmalloc_reserve = SZ_16M;
881 printk(KERN_WARNING
882 "vmalloc area too small, limiting to %luMB\n",
883 vmalloc_reserve >> 20);
884 }
885
886 if (vmalloc_reserve > VMALLOC_END - (PAGE_OFFSET + SZ_32M)) {
887 vmalloc_reserve = VMALLOC_END - (PAGE_OFFSET + SZ_32M);
888 printk(KERN_WARNING
889 "vmalloc area is too big, limiting to %luMB\n",
890 vmalloc_reserve >> 20);
891 }
892
893 vmalloc_min = (void *)(VMALLOC_END - vmalloc_reserve);
894 return 0;
895 }
896 early_param("vmalloc", early_vmalloc);
897
898 phys_addr_t arm_lowmem_limit __initdata = 0;
899
900 void __init sanity_check_meminfo(void)
901 {
902 int i, j, highmem = 0;
903
904 for (i = 0, j = 0; i < meminfo.nr_banks; i++) {
905 struct membank *bank = &meminfo.bank[j];
906 *bank = meminfo.bank[i];
907
908 if (bank->start > ULONG_MAX)
909 highmem = 1;
910
911 #ifdef CONFIG_HIGHMEM
912 if (__va(bank->start) >= vmalloc_min ||
913 __va(bank->start) < (void *)PAGE_OFFSET)
914 highmem = 1;
915
916 bank->highmem = highmem;
917
918 /*
919 * Split those memory banks which are partially overlapping
920 * the vmalloc area greatly simplifying things later.
921 */
922 if (!highmem && __va(bank->start) < vmalloc_min &&
923 bank->size > vmalloc_min - __va(bank->start)) {
924 if (meminfo.nr_banks >= NR_BANKS) {
925 printk(KERN_CRIT "NR_BANKS too low, "
926 "ignoring high memory\n");
927 } else {
928 memmove(bank + 1, bank,
929 (meminfo.nr_banks - i) * sizeof(*bank));
930 meminfo.nr_banks++;
931 i++;
932 bank[1].size -= vmalloc_min - __va(bank->start);
933 bank[1].start = __pa(vmalloc_min - 1) + 1;
934 bank[1].highmem = highmem = 1;
935 j++;
936 }
937 bank->size = vmalloc_min - __va(bank->start);
938 }
939 #else
940 bank->highmem = highmem;
941
942 /*
943 * Highmem banks not allowed with !CONFIG_HIGHMEM.
944 */
945 if (highmem) {
946 printk(KERN_NOTICE "Ignoring RAM at %.8llx-%.8llx "
947 "(!CONFIG_HIGHMEM).\n",
948 (unsigned long long)bank->start,
949 (unsigned long long)bank->start + bank->size - 1);
950 continue;
951 }
952
953 /*
954 * Check whether this memory bank would entirely overlap
955 * the vmalloc area.
956 */
957 if (__va(bank->start) >= vmalloc_min ||
958 __va(bank->start) < (void *)PAGE_OFFSET) {
959 printk(KERN_NOTICE "Ignoring RAM at %.8llx-%.8llx "
960 "(vmalloc region overlap).\n",
961 (unsigned long long)bank->start,
962 (unsigned long long)bank->start + bank->size - 1);
963 continue;
964 }
965
966 /*
967 * Check whether this memory bank would partially overlap
968 * the vmalloc area.
969 */
970 if (__va(bank->start + bank->size) > vmalloc_min ||
971 __va(bank->start + bank->size) < __va(bank->start)) {
972 unsigned long newsize = vmalloc_min - __va(bank->start);
973 printk(KERN_NOTICE "Truncating RAM at %.8llx-%.8llx "
974 "to -%.8llx (vmalloc region overlap).\n",
975 (unsigned long long)bank->start,
976 (unsigned long long)bank->start + bank->size - 1,
977 (unsigned long long)bank->start + newsize - 1);
978 bank->size = newsize;
979 }
980 #endif
981 if (!bank->highmem && bank->start + bank->size > arm_lowmem_limit)
982 arm_lowmem_limit = bank->start + bank->size;
983
984 j++;
985 }
986 #ifdef CONFIG_HIGHMEM
987 if (highmem) {
988 const char *reason = NULL;
989
990 if (cache_is_vipt_aliasing()) {
991 /*
992 * Interactions between kmap and other mappings
993 * make highmem support with aliasing VIPT caches
994 * rather difficult.
995 */
996 reason = "with VIPT aliasing cache";
997 }
998 if (reason) {
999 printk(KERN_CRIT "HIGHMEM is not supported %s, ignoring high memory\n",
1000 reason);
1001 while (j > 0 && meminfo.bank[j - 1].highmem)
1002 j--;
1003 }
1004 }
1005 #endif
1006 meminfo.nr_banks = j;
1007 high_memory = __va(arm_lowmem_limit - 1) + 1;
1008 memblock_set_current_limit(arm_lowmem_limit);
1009 }
1010
1011 static inline void prepare_page_table(void)
1012 {
1013 unsigned long addr;
1014 phys_addr_t end;
1015
1016 /*
1017 * Clear out all the mappings below the kernel image.
1018 */
1019 for (addr = 0; addr < MODULES_VADDR; addr += PMD_SIZE)
1020 pmd_clear(pmd_off_k(addr));
1021
1022 #ifdef CONFIG_XIP_KERNEL
1023 /* The XIP kernel is mapped in the module area -- skip over it */
1024 addr = ((unsigned long)_etext + PMD_SIZE - 1) & PMD_MASK;
1025 #endif
1026 for ( ; addr < PAGE_OFFSET; addr += PMD_SIZE)
1027 pmd_clear(pmd_off_k(addr));
1028
1029 /*
1030 * Find the end of the first block of lowmem.
1031 */
1032 end = memblock.memory.regions[0].base + memblock.memory.regions[0].size;
1033 if (end >= arm_lowmem_limit)
1034 end = arm_lowmem_limit;
1035
1036 /*
1037 * Clear out all the kernel space mappings, except for the first
1038 * memory bank, up to the vmalloc region.
1039 */
1040 for (addr = __phys_to_virt(end);
1041 addr < VMALLOC_START; addr += PMD_SIZE)
1042 pmd_clear(pmd_off_k(addr));
1043 }
1044
1045 #ifdef CONFIG_ARM_LPAE
1046 /* the first page is reserved for pgd */
1047 #define SWAPPER_PG_DIR_SIZE (PAGE_SIZE + \
1048 PTRS_PER_PGD * PTRS_PER_PMD * sizeof(pmd_t))
1049 #else
1050 #define SWAPPER_PG_DIR_SIZE (PTRS_PER_PGD * sizeof(pgd_t))
1051 #endif
1052
1053 /*
1054 * Reserve the special regions of memory
1055 */
1056 void __init arm_mm_memblock_reserve(void)
1057 {
1058 /*
1059 * Reserve the page tables. These are already in use,
1060 * and can only be in node 0.
1061 */
1062 memblock_reserve(__pa(swapper_pg_dir), SWAPPER_PG_DIR_SIZE);
1063
1064 #ifdef CONFIG_SA1111
1065 /*
1066 * Because of the SA1111 DMA bug, we want to preserve our
1067 * precious DMA-able memory...
1068 */
1069 memblock_reserve(PHYS_OFFSET, __pa(swapper_pg_dir) - PHYS_OFFSET);
1070 #endif
1071 }
1072
1073 /*
1074 * Set up the device mappings. Since we clear out the page tables for all
1075 * mappings above VMALLOC_START, we will remove any debug device mappings.
1076 * This means you have to be careful how you debug this function, or any
1077 * called function. This means you can't use any function or debugging
1078 * method which may touch any device, otherwise the kernel _will_ crash.
1079 */
1080 static void __init devicemaps_init(struct machine_desc *mdesc)
1081 {
1082 struct map_desc map;
1083 unsigned long addr;
1084 void *vectors;
1085
1086 /*
1087 * Allocate the vector page early.
1088 */
1089 vectors = early_alloc(PAGE_SIZE);
1090
1091 early_trap_init(vectors);
1092
1093 for (addr = VMALLOC_START; addr; addr += PMD_SIZE)
1094 pmd_clear(pmd_off_k(addr));
1095
1096 /*
1097 * Map the kernel if it is XIP.
1098 * It is always first in the modulearea.
1099 */
1100 #ifdef CONFIG_XIP_KERNEL
1101 map.pfn = __phys_to_pfn(CONFIG_XIP_PHYS_ADDR & SECTION_MASK);
1102 map.virtual = MODULES_VADDR;
1103 map.length = ((unsigned long)_etext - map.virtual + ~SECTION_MASK) & SECTION_MASK;
1104 map.type = MT_ROM;
1105 create_mapping(&map);
1106 #endif
1107
1108 /*
1109 * Map the cache flushing regions.
1110 */
1111 #ifdef FLUSH_BASE
1112 map.pfn = __phys_to_pfn(FLUSH_BASE_PHYS);
1113 map.virtual = FLUSH_BASE;
1114 map.length = SZ_1M;
1115 map.type = MT_CACHECLEAN;
1116 create_mapping(&map);
1117 #endif
1118 #ifdef FLUSH_BASE_MINICACHE
1119 map.pfn = __phys_to_pfn(FLUSH_BASE_PHYS + SZ_1M);
1120 map.virtual = FLUSH_BASE_MINICACHE;
1121 map.length = SZ_1M;
1122 map.type = MT_MINICLEAN;
1123 create_mapping(&map);
1124 #endif
1125
1126 /*
1127 * Create a mapping for the machine vectors at the high-vectors
1128 * location (0xffff0000). If we aren't using high-vectors, also
1129 * create a mapping at the low-vectors virtual address.
1130 */
1131 map.pfn = __phys_to_pfn(virt_to_phys(vectors));
1132 map.virtual = 0xffff0000;
1133 map.length = PAGE_SIZE;
1134 map.type = MT_HIGH_VECTORS;
1135 create_mapping(&map);
1136
1137 if (!vectors_high()) {
1138 map.virtual = 0;
1139 map.type = MT_LOW_VECTORS;
1140 create_mapping(&map);
1141 }
1142
1143 /*
1144 * Ask the machine support to map in the statically mapped devices.
1145 */
1146 if (mdesc->map_io)
1147 mdesc->map_io();
1148 fill_pmd_gaps();
1149
1150 /*
1151 * Finally flush the caches and tlb to ensure that we're in a
1152 * consistent state wrt the writebuffer. This also ensures that
1153 * any write-allocated cache lines in the vector page are written
1154 * back. After this point, we can start to touch devices again.
1155 */
1156 local_flush_tlb_all();
1157 flush_cache_all();
1158 }
1159
1160 static void __init kmap_init(void)
1161 {
1162 #ifdef CONFIG_HIGHMEM
1163 pkmap_page_table = early_pte_alloc(pmd_off_k(PKMAP_BASE),
1164 PKMAP_BASE, _PAGE_KERNEL_TABLE);
1165 #endif
1166 }
1167
1168 static void __init map_lowmem(void)
1169 {
1170 struct memblock_region *reg;
1171
1172 /* Map all the lowmem memory banks. */
1173 for_each_memblock(memory, reg) {
1174 phys_addr_t start = reg->base;
1175 phys_addr_t end = start + reg->size;
1176 struct map_desc map;
1177
1178 if (end > arm_lowmem_limit)
1179 end = arm_lowmem_limit;
1180 if (start >= end)
1181 break;
1182
1183 map.pfn = __phys_to_pfn(start);
1184 map.virtual = __phys_to_virt(start);
1185 map.length = end - start;
1186 map.type = MT_MEMORY;
1187
1188 create_mapping(&map);
1189 }
1190 }
1191
1192 /*
1193 * paging_init() sets up the page tables, initialises the zone memory
1194 * maps, and sets up the zero page, bad page and bad page tables.
1195 */
1196 void __init paging_init(struct machine_desc *mdesc)
1197 {
1198 void *zero_page;
1199
1200 memblock_set_current_limit(arm_lowmem_limit);
1201
1202 build_mem_type_table();
1203 prepare_page_table();
1204 map_lowmem();
1205 dma_contiguous_remap();
1206 devicemaps_init(mdesc);
1207 kmap_init();
1208
1209 top_pmd = pmd_off_k(0xffff0000);
1210
1211 /* allocate the zero page. */
1212 zero_page = early_alloc(PAGE_SIZE);
1213
1214 bootmem_init();
1215
1216 empty_zero_page = virt_to_page(zero_page);
1217 __flush_dcache_page(NULL, empty_zero_page);
1218 }
kernel source for telekom puls (alcatel/mediatek)