Merge tag 'lsk-android-14.03' into develop-3.10
[firefly-linux-kernel-4.4.55.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 #include <linux/sizes.h>
20
21 #include <asm/cp15.h>
22 #include <asm/cputype.h>
23 #include <asm/sections.h>
24 #include <asm/cachetype.h>
25 #include <asm/setup.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 #include <asm/mach/pci.h>
35
36 #include "mm.h"
37 #include "tcm.h"
38
39 /*
40  * empty_zero_page is a special page that is used for
41  * zero-initialized data and COW.
42  */
43 struct page *empty_zero_page;
44 EXPORT_SYMBOL(empty_zero_page);
45
46 /*
47  * The pmd table for the upper-most set of pages.
48  */
49 pmd_t *top_pmd;
50
51 #define CPOLICY_UNCACHED        0
52 #define CPOLICY_BUFFERED        1
53 #define CPOLICY_WRITETHROUGH    2
54 #define CPOLICY_WRITEBACK       3
55 #define CPOLICY_WRITEALLOC      4
56
57 static unsigned int cachepolicy __initdata = CPOLICY_WRITEBACK;
58 static unsigned int ecc_mask __initdata = 0;
59 pgprot_t pgprot_user;
60 pgprot_t pgprot_kernel;
61 pgprot_t pgprot_hyp_device;
62 pgprot_t pgprot_s2;
63 pgprot_t pgprot_s2_device;
64
65 EXPORT_SYMBOL(pgprot_user);
66 EXPORT_SYMBOL(pgprot_kernel);
67
68 struct cachepolicy {
69         const char      policy[16];
70         unsigned int    cr_mask;
71         pmdval_t        pmd;
72         pteval_t        pte;
73         pteval_t        pte_s2;
74 };
75
76 #ifdef CONFIG_ARM_LPAE
77 #define s2_policy(policy)       policy
78 #else
79 #define s2_policy(policy)       0
80 #endif
81
82 static struct cachepolicy cache_policies[] __initdata = {
83         {
84                 .policy         = "uncached",
85                 .cr_mask        = CR_W|CR_C,
86                 .pmd            = PMD_SECT_UNCACHED,
87                 .pte            = L_PTE_MT_UNCACHED,
88                 .pte_s2         = s2_policy(L_PTE_S2_MT_UNCACHED),
89         }, {
90                 .policy         = "buffered",
91                 .cr_mask        = CR_C,
92                 .pmd            = PMD_SECT_BUFFERED,
93                 .pte            = L_PTE_MT_BUFFERABLE,
94                 .pte_s2         = s2_policy(L_PTE_S2_MT_UNCACHED),
95         }, {
96                 .policy         = "writethrough",
97                 .cr_mask        = 0,
98                 .pmd            = PMD_SECT_WT,
99                 .pte            = L_PTE_MT_WRITETHROUGH,
100                 .pte_s2         = s2_policy(L_PTE_S2_MT_WRITETHROUGH),
101         }, {
102                 .policy         = "writeback",
103                 .cr_mask        = 0,
104                 .pmd            = PMD_SECT_WB,
105                 .pte            = L_PTE_MT_WRITEBACK,
106                 .pte_s2         = s2_policy(L_PTE_S2_MT_WRITEBACK),
107         }, {
108                 .policy         = "writealloc",
109                 .cr_mask        = 0,
110                 .pmd            = PMD_SECT_WBWA,
111                 .pte            = L_PTE_MT_WRITEALLOC,
112                 .pte_s2         = s2_policy(L_PTE_S2_MT_WRITEBACK),
113         }
114 };
115
116 #ifdef CONFIG_CPU_CP15
117 /*
118  * These are useful for identifying cache coherency
119  * problems by allowing the cache or the cache and
120  * writebuffer to be turned off.  (Note: the write
121  * buffer should not be on and the cache off).
122  */
123 static int __init early_cachepolicy(char *p)
124 {
125         int i;
126
127         for (i = 0; i < ARRAY_SIZE(cache_policies); i++) {
128                 int len = strlen(cache_policies[i].policy);
129
130                 if (memcmp(p, cache_policies[i].policy, len) == 0) {
131                         cachepolicy = i;
132                         cr_alignment &= ~cache_policies[i].cr_mask;
133                         cr_no_alignment &= ~cache_policies[i].cr_mask;
134                         break;
135                 }
136         }
137         if (i == ARRAY_SIZE(cache_policies))
138                 printk(KERN_ERR "ERROR: unknown or unsupported cache policy\n");
139         /*
140          * This restriction is partly to do with the way we boot; it is
141          * unpredictable to have memory mapped using two different sets of
142          * memory attributes (shared, type, and cache attribs).  We can not
143          * change these attributes once the initial assembly has setup the
144          * page tables.
145          */
146         if (cpu_architecture() >= CPU_ARCH_ARMv6) {
147                 printk(KERN_WARNING "Only cachepolicy=writeback supported on ARMv6 and later\n");
148                 cachepolicy = CPOLICY_WRITEBACK;
149         }
150         flush_cache_all();
151         set_cr(cr_alignment);
152         return 0;
153 }
154 early_param("cachepolicy", early_cachepolicy);
155
156 static int __init early_nocache(char *__unused)
157 {
158         char *p = "buffered";
159         printk(KERN_WARNING "nocache is deprecated; use cachepolicy=%s\n", p);
160         early_cachepolicy(p);
161         return 0;
162 }
163 early_param("nocache", early_nocache);
164
165 static int __init early_nowrite(char *__unused)
166 {
167         char *p = "uncached";
168         printk(KERN_WARNING "nowb is deprecated; use cachepolicy=%s\n", p);
169         early_cachepolicy(p);
170         return 0;
171 }
172 early_param("nowb", early_nowrite);
173
174 #ifndef CONFIG_ARM_LPAE
175 static int __init early_ecc(char *p)
176 {
177         if (memcmp(p, "on", 2) == 0)
178                 ecc_mask = PMD_PROTECTION;
179         else if (memcmp(p, "off", 3) == 0)
180                 ecc_mask = 0;
181         return 0;
182 }
183 early_param("ecc", early_ecc);
184 #endif
185
186 static int __init noalign_setup(char *__unused)
187 {
188         cr_alignment &= ~CR_A;
189         cr_no_alignment &= ~CR_A;
190         set_cr(cr_alignment);
191         return 1;
192 }
193 __setup("noalign", noalign_setup);
194
195 #ifndef CONFIG_SMP
196 void adjust_cr(unsigned long mask, unsigned long set)
197 {
198         unsigned long flags;
199
200         mask &= ~CR_A;
201
202         set &= mask;
203
204         local_irq_save(flags);
205
206         cr_no_alignment = (cr_no_alignment & ~mask) | set;
207         cr_alignment = (cr_alignment & ~mask) | set;
208
209         set_cr((get_cr() & ~mask) | set);
210
211         local_irq_restore(flags);
212 }
213 #endif
214
215 #else /* ifdef CONFIG_CPU_CP15 */
216
217 static int __init early_cachepolicy(char *p)
218 {
219         pr_warning("cachepolicy kernel parameter not supported without cp15\n");
220 }
221 early_param("cachepolicy", early_cachepolicy);
222
223 static int __init noalign_setup(char *__unused)
224 {
225         pr_warning("noalign kernel parameter not supported without cp15\n");
226 }
227 __setup("noalign", noalign_setup);
228
229 #endif /* ifdef CONFIG_CPU_CP15 / else */
230
231 #define PROT_PTE_DEVICE         L_PTE_PRESENT|L_PTE_YOUNG|L_PTE_DIRTY|L_PTE_XN
232 #define PROT_SECT_DEVICE        PMD_TYPE_SECT|PMD_SECT_AP_WRITE
233
234 static struct mem_type mem_types[] = {
235         [MT_DEVICE] = {           /* Strongly ordered / ARMv6 shared device */
236                 .prot_pte       = PROT_PTE_DEVICE | L_PTE_MT_DEV_SHARED |
237                                   L_PTE_SHARED,
238                 .prot_l1        = PMD_TYPE_TABLE,
239                 .prot_sect      = PROT_SECT_DEVICE | PMD_SECT_S,
240                 .domain         = DOMAIN_IO,
241         },
242         [MT_DEVICE_NONSHARED] = { /* ARMv6 non-shared device */
243                 .prot_pte       = PROT_PTE_DEVICE | L_PTE_MT_DEV_NONSHARED,
244                 .prot_l1        = PMD_TYPE_TABLE,
245                 .prot_sect      = PROT_SECT_DEVICE,
246                 .domain         = DOMAIN_IO,
247         },
248         [MT_DEVICE_CACHED] = {    /* ioremap_cached */
249                 .prot_pte       = PROT_PTE_DEVICE | L_PTE_MT_DEV_CACHED,
250                 .prot_l1        = PMD_TYPE_TABLE,
251                 .prot_sect      = PROT_SECT_DEVICE | PMD_SECT_WB,
252                 .domain         = DOMAIN_IO,
253         },
254         [MT_DEVICE_WC] = {      /* ioremap_wc */
255                 .prot_pte       = PROT_PTE_DEVICE | L_PTE_MT_DEV_WC,
256                 .prot_l1        = PMD_TYPE_TABLE,
257                 .prot_sect      = PROT_SECT_DEVICE,
258                 .domain         = DOMAIN_IO,
259         },
260         [MT_UNCACHED] = {
261                 .prot_pte       = PROT_PTE_DEVICE,
262                 .prot_l1        = PMD_TYPE_TABLE,
263                 .prot_sect      = PMD_TYPE_SECT | PMD_SECT_XN,
264                 .domain         = DOMAIN_IO,
265         },
266         [MT_CACHECLEAN] = {
267                 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
268                 .domain    = DOMAIN_KERNEL,
269         },
270 #ifndef CONFIG_ARM_LPAE
271         [MT_MINICLEAN] = {
272                 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN | PMD_SECT_MINICACHE,
273                 .domain    = DOMAIN_KERNEL,
274         },
275 #endif
276         [MT_LOW_VECTORS] = {
277                 .prot_pte  = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
278                                 L_PTE_RDONLY,
279                 .prot_l1   = PMD_TYPE_TABLE,
280                 .domain    = DOMAIN_USER,
281         },
282         [MT_HIGH_VECTORS] = {
283                 .prot_pte  = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
284                                 L_PTE_USER | L_PTE_RDONLY,
285                 .prot_l1   = PMD_TYPE_TABLE,
286                 .domain    = DOMAIN_USER,
287         },
288         [MT_MEMORY] = {
289                 .prot_pte  = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
290                 .prot_l1   = PMD_TYPE_TABLE,
291                 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
292                 .domain    = DOMAIN_KERNEL,
293         },
294         [MT_ROM] = {
295                 .prot_sect = PMD_TYPE_SECT,
296                 .domain    = DOMAIN_KERNEL,
297         },
298         [MT_MEMORY_NONCACHED] = {
299                 .prot_pte  = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
300                                 L_PTE_MT_BUFFERABLE,
301                 .prot_l1   = PMD_TYPE_TABLE,
302                 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
303                 .domain    = DOMAIN_KERNEL,
304         },
305         [MT_MEMORY_DTCM] = {
306                 .prot_pte  = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
307                                 L_PTE_XN,
308                 .prot_l1   = PMD_TYPE_TABLE,
309                 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
310                 .domain    = DOMAIN_KERNEL,
311         },
312         [MT_MEMORY_ITCM] = {
313                 .prot_pte  = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
314                 .prot_l1   = PMD_TYPE_TABLE,
315                 .domain    = DOMAIN_KERNEL,
316         },
317         [MT_MEMORY_SO] = {
318                 .prot_pte  = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
319                                 L_PTE_MT_UNCACHED | L_PTE_XN,
320                 .prot_l1   = PMD_TYPE_TABLE,
321                 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_SECT_S |
322                                 PMD_SECT_UNCACHED | PMD_SECT_XN,
323                 .domain    = DOMAIN_KERNEL,
324         },
325         [MT_MEMORY_DMA_READY] = {
326                 .prot_pte  = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
327                 .prot_l1   = PMD_TYPE_TABLE,
328                 .domain    = DOMAIN_KERNEL,
329         },
330 };
331
332 const struct mem_type *get_mem_type(unsigned int type)
333 {
334         return type < ARRAY_SIZE(mem_types) ? &mem_types[type] : NULL;
335 }
336 EXPORT_SYMBOL(get_mem_type);
337
338 /*
339  * Adjust the PMD section entries according to the CPU in use.
340  */
341 static void __init build_mem_type_table(void)
342 {
343         struct cachepolicy *cp;
344         unsigned int cr = get_cr();
345         pteval_t user_pgprot, kern_pgprot, vecs_pgprot;
346         pteval_t hyp_device_pgprot, s2_pgprot, s2_device_pgprot;
347         int cpu_arch = cpu_architecture();
348         int i;
349
350         if (cpu_arch < CPU_ARCH_ARMv6) {
351 #if defined(CONFIG_CPU_DCACHE_DISABLE)
352                 if (cachepolicy > CPOLICY_BUFFERED)
353                         cachepolicy = CPOLICY_BUFFERED;
354 #elif defined(CONFIG_CPU_DCACHE_WRITETHROUGH)
355                 if (cachepolicy > CPOLICY_WRITETHROUGH)
356                         cachepolicy = CPOLICY_WRITETHROUGH;
357 #endif
358         }
359         if (cpu_arch < CPU_ARCH_ARMv5) {
360                 if (cachepolicy >= CPOLICY_WRITEALLOC)
361                         cachepolicy = CPOLICY_WRITEBACK;
362                 ecc_mask = 0;
363         }
364         if (is_smp())
365                 cachepolicy = CPOLICY_WRITEALLOC;
366
367         /*
368          * Strip out features not present on earlier architectures.
369          * Pre-ARMv5 CPUs don't have TEX bits.  Pre-ARMv6 CPUs or those
370          * without extended page tables don't have the 'Shared' bit.
371          */
372         if (cpu_arch < CPU_ARCH_ARMv5)
373                 for (i = 0; i < ARRAY_SIZE(mem_types); i++)
374                         mem_types[i].prot_sect &= ~PMD_SECT_TEX(7);
375         if ((cpu_arch < CPU_ARCH_ARMv6 || !(cr & CR_XP)) && !cpu_is_xsc3())
376                 for (i = 0; i < ARRAY_SIZE(mem_types); i++)
377                         mem_types[i].prot_sect &= ~PMD_SECT_S;
378
379         /*
380          * ARMv5 and lower, bit 4 must be set for page tables (was: cache
381          * "update-able on write" bit on ARM610).  However, Xscale and
382          * Xscale3 require this bit to be cleared.
383          */
384         if (cpu_is_xscale() || cpu_is_xsc3()) {
385                 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
386                         mem_types[i].prot_sect &= ~PMD_BIT4;
387                         mem_types[i].prot_l1 &= ~PMD_BIT4;
388                 }
389         } else if (cpu_arch < CPU_ARCH_ARMv6) {
390                 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
391                         if (mem_types[i].prot_l1)
392                                 mem_types[i].prot_l1 |= PMD_BIT4;
393                         if (mem_types[i].prot_sect)
394                                 mem_types[i].prot_sect |= PMD_BIT4;
395                 }
396         }
397
398         /*
399          * Mark the device areas according to the CPU/architecture.
400          */
401         if (cpu_is_xsc3() || (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP))) {
402                 if (!cpu_is_xsc3()) {
403                         /*
404                          * Mark device regions on ARMv6+ as execute-never
405                          * to prevent speculative instruction fetches.
406                          */
407                         mem_types[MT_DEVICE].prot_sect |= PMD_SECT_XN;
408                         mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_XN;
409                         mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_XN;
410                         mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_XN;
411                 }
412                 if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
413                         /*
414                          * For ARMv7 with TEX remapping,
415                          * - shared device is SXCB=1100
416                          * - nonshared device is SXCB=0100
417                          * - write combine device mem is SXCB=0001
418                          * (Uncached Normal memory)
419                          */
420                         mem_types[MT_DEVICE].prot_sect |= PMD_SECT_TEX(1);
421                         mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(1);
422                         mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_BUFFERABLE;
423                 } else if (cpu_is_xsc3()) {
424                         /*
425                          * For Xscale3,
426                          * - shared device is TEXCB=00101
427                          * - nonshared device is TEXCB=01000
428                          * - write combine device mem is TEXCB=00100
429                          * (Inner/Outer Uncacheable in xsc3 parlance)
430                          */
431                         mem_types[MT_DEVICE].prot_sect |= PMD_SECT_TEX(1) | PMD_SECT_BUFFERED;
432                         mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(2);
433                         mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1);
434                 } else {
435                         /*
436                          * For ARMv6 and ARMv7 without TEX remapping,
437                          * - shared device is TEXCB=00001
438                          * - nonshared device is TEXCB=01000
439                          * - write combine device mem is TEXCB=00100
440                          * (Uncached Normal in ARMv6 parlance).
441                          */
442                         mem_types[MT_DEVICE].prot_sect |= PMD_SECT_BUFFERED;
443                         mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_TEX(2);
444                         mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1);
445                 }
446         } else {
447                 /*
448                  * On others, write combining is "Uncached/Buffered"
449                  */
450                 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_BUFFERABLE;
451         }
452
453         /*
454          * Now deal with the memory-type mappings
455          */
456         cp = &cache_policies[cachepolicy];
457         vecs_pgprot = kern_pgprot = user_pgprot = cp->pte;
458         s2_pgprot = cp->pte_s2;
459         hyp_device_pgprot = s2_device_pgprot = mem_types[MT_DEVICE].prot_pte;
460
461         /*
462          * ARMv6 and above have extended page tables.
463          */
464         if (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP)) {
465 #ifndef CONFIG_ARM_LPAE
466                 /*
467                  * Mark cache clean areas and XIP ROM read only
468                  * from SVC mode and no access from userspace.
469                  */
470                 mem_types[MT_ROM].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
471                 mem_types[MT_MINICLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
472                 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
473 #endif
474
475                 if (is_smp()) {
476                         /*
477                          * Mark memory with the "shared" attribute
478                          * for SMP systems
479                          */
480                         user_pgprot |= L_PTE_SHARED;
481                         kern_pgprot |= L_PTE_SHARED;
482                         vecs_pgprot |= L_PTE_SHARED;
483                         s2_pgprot |= L_PTE_SHARED;
484                         mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_S;
485                         mem_types[MT_DEVICE_WC].prot_pte |= L_PTE_SHARED;
486                         mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_S;
487                         mem_types[MT_DEVICE_CACHED].prot_pte |= L_PTE_SHARED;
488                         mem_types[MT_MEMORY].prot_sect |= PMD_SECT_S;
489                         mem_types[MT_MEMORY].prot_pte |= L_PTE_SHARED;
490                         mem_types[MT_MEMORY_DMA_READY].prot_pte |= L_PTE_SHARED;
491                         mem_types[MT_MEMORY_NONCACHED].prot_sect |= PMD_SECT_S;
492                         mem_types[MT_MEMORY_NONCACHED].prot_pte |= L_PTE_SHARED;
493                 }
494         }
495
496         /*
497          * Non-cacheable Normal - intended for memory areas that must
498          * not cause dirty cache line writebacks when used
499          */
500         if (cpu_arch >= CPU_ARCH_ARMv6) {
501                 if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
502                         /* Non-cacheable Normal is XCB = 001 */
503                         mem_types[MT_MEMORY_NONCACHED].prot_sect |=
504                                 PMD_SECT_BUFFERED;
505                 } else {
506                         /* For both ARMv6 and non-TEX-remapping ARMv7 */
507                         mem_types[MT_MEMORY_NONCACHED].prot_sect |=
508                                 PMD_SECT_TEX(1);
509                 }
510         } else {
511                 mem_types[MT_MEMORY_NONCACHED].prot_sect |= PMD_SECT_BUFFERABLE;
512         }
513
514 #ifdef CONFIG_ARM_LPAE
515         /*
516          * Do not generate access flag faults for the kernel mappings.
517          */
518         for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
519                 mem_types[i].prot_pte |= PTE_EXT_AF;
520                 if (mem_types[i].prot_sect)
521                         mem_types[i].prot_sect |= PMD_SECT_AF;
522         }
523         kern_pgprot |= PTE_EXT_AF;
524         vecs_pgprot |= PTE_EXT_AF;
525 #endif
526
527         for (i = 0; i < 16; i++) {
528                 pteval_t v = pgprot_val(protection_map[i]);
529                 protection_map[i] = __pgprot(v | user_pgprot);
530         }
531
532         mem_types[MT_LOW_VECTORS].prot_pte |= vecs_pgprot;
533         mem_types[MT_HIGH_VECTORS].prot_pte |= vecs_pgprot;
534
535         pgprot_user   = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | user_pgprot);
536         pgprot_kernel = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG |
537                                  L_PTE_DIRTY | kern_pgprot);
538         pgprot_s2  = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | s2_pgprot);
539         pgprot_s2_device  = __pgprot(s2_device_pgprot);
540         pgprot_hyp_device  = __pgprot(hyp_device_pgprot);
541
542         mem_types[MT_LOW_VECTORS].prot_l1 |= ecc_mask;
543         mem_types[MT_HIGH_VECTORS].prot_l1 |= ecc_mask;
544         mem_types[MT_MEMORY].prot_sect |= ecc_mask | cp->pmd;
545         mem_types[MT_MEMORY].prot_pte |= kern_pgprot;
546         mem_types[MT_MEMORY_DMA_READY].prot_pte |= kern_pgprot;
547         mem_types[MT_MEMORY_NONCACHED].prot_sect |= ecc_mask;
548         mem_types[MT_ROM].prot_sect |= cp->pmd;
549
550         switch (cp->pmd) {
551         case PMD_SECT_WT:
552                 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WT;
553                 break;
554         case PMD_SECT_WB:
555         case PMD_SECT_WBWA:
556                 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WB;
557                 break;
558         }
559         printk("Memory policy: ECC %sabled, Data cache %s\n",
560                 ecc_mask ? "en" : "dis", cp->policy);
561
562         for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
563                 struct mem_type *t = &mem_types[i];
564                 if (t->prot_l1)
565                         t->prot_l1 |= PMD_DOMAIN(t->domain);
566                 if (t->prot_sect)
567                         t->prot_sect |= PMD_DOMAIN(t->domain);
568         }
569 }
570
571 #ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
572 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
573                               unsigned long size, pgprot_t vma_prot)
574 {
575         if (!pfn_valid(pfn))
576                 return pgprot_noncached(vma_prot);
577         else if (file->f_flags & O_SYNC)
578                 return pgprot_writecombine(vma_prot);
579         return vma_prot;
580 }
581 EXPORT_SYMBOL(phys_mem_access_prot);
582 #endif
583
584 #define vectors_base()  (vectors_high() ? 0xffff0000 : 0)
585
586 static void __init *early_alloc_aligned(unsigned long sz, unsigned long align)
587 {
588         void *ptr = __va(memblock_alloc(sz, align));
589         memset(ptr, 0, sz);
590         return ptr;
591 }
592
593 static void __init *early_alloc(unsigned long sz)
594 {
595         return early_alloc_aligned(sz, sz);
596 }
597
598 static pte_t * __init early_pte_alloc(pmd_t *pmd)
599 {
600         if (pmd_none(*pmd) || pmd_bad(*pmd))
601                 return early_alloc(PTE_HWTABLE_OFF + PTE_HWTABLE_SIZE);
602         return pmd_page_vaddr(*pmd);
603 }
604
605 static void __init early_pte_install(pmd_t *pmd, pte_t *pte, unsigned long prot)
606 {
607         __pmd_populate(pmd, __pa(pte), prot);
608         BUG_ON(pmd_bad(*pmd));
609 }
610
611 static pte_t * __init early_pte_alloc_and_install(pmd_t *pmd,
612         unsigned long addr, unsigned long prot)
613 {
614         if (pmd_none(*pmd)) {
615                 pte_t *pte = early_pte_alloc(pmd);
616                 early_pte_install(pmd, pte, prot);
617         }
618         BUG_ON(pmd_bad(*pmd));
619         return pte_offset_kernel(pmd, addr);
620 }
621
622 static void __init alloc_init_pte(pmd_t *pmd, unsigned long addr,
623                                   unsigned long end, unsigned long pfn,
624                                   const struct mem_type *type)
625 {
626         pte_t *start_pte = early_pte_alloc(pmd);
627         pte_t *pte = start_pte + pte_index(addr);
628
629         /* If replacing a section mapping, the whole section must be replaced */
630         BUG_ON(!pmd_none(*pmd) && pmd_bad(*pmd) && ((addr | end) & ~PMD_MASK));
631
632         do {
633                 set_pte_ext(pte, pfn_pte(pfn, __pgprot(type->prot_pte)), 0);
634                 pfn++;
635         } while (pte++, addr += PAGE_SIZE, addr != end);
636         early_pte_install(pmd, start_pte, type->prot_l1);
637 }
638
639 static void __init __map_init_section(pmd_t *pmd, unsigned long addr,
640                         unsigned long end, phys_addr_t phys,
641                         const struct mem_type *type)
642 {
643         pmd_t *p = pmd;
644
645 #ifndef CONFIG_ARM_LPAE
646         /*
647          * In classic MMU format, puds and pmds are folded in to
648          * the pgds. pmd_offset gives the PGD entry. PGDs refer to a
649          * group of L1 entries making up one logical pointer to
650          * an L2 table (2MB), where as PMDs refer to the individual
651          * L1 entries (1MB). Hence increment to get the correct
652          * offset for odd 1MB sections.
653          * (See arch/arm/include/asm/pgtable-2level.h)
654          */
655         if (addr & SECTION_SIZE)
656                 pmd++;
657 #endif
658         do {
659                 *pmd = __pmd(phys | type->prot_sect);
660                 phys += SECTION_SIZE;
661         } while (pmd++, addr += SECTION_SIZE, addr != end);
662
663         flush_pmd_entry(p);
664 }
665
666 static void __init alloc_init_pmd(pud_t *pud, unsigned long addr,
667                                       unsigned long end, phys_addr_t phys,
668                                       const struct mem_type *type,
669                                       bool force_pages)
670 {
671         pmd_t *pmd = pmd_offset(pud, addr);
672         unsigned long next;
673
674         do {
675                 /*
676                  * With LPAE, we must loop over to map
677                  * all the pmds for the given range.
678                  */
679                 next = pmd_addr_end(addr, end);
680
681                 /*
682                  * Try a section mapping - addr, next and phys must all be
683                  * aligned to a section boundary.
684                  */
685                 if (type->prot_sect &&
686                                 ((addr | next | phys) & ~SECTION_MASK) == 0 &&
687                                 !force_pages) {
688                         __map_init_section(pmd, addr, next, phys, type);
689                 } else {
690                         alloc_init_pte(pmd, addr, next,
691                                                 __phys_to_pfn(phys), type);
692                 }
693
694                 phys += next - addr;
695
696         } while (pmd++, addr = next, addr != end);
697 }
698
699 static void __init alloc_init_pud(pgd_t *pgd, unsigned long addr,
700         unsigned long end, unsigned long phys, const struct mem_type *type,
701         bool force_pages)
702 {
703         pud_t *pud = pud_offset(pgd, addr);
704         unsigned long next;
705
706         do {
707                 next = pud_addr_end(addr, end);
708                 alloc_init_pmd(pud, addr, next, phys, type, force_pages);
709                 phys += next - addr;
710         } while (pud++, addr = next, addr != end);
711 }
712
713 #ifndef CONFIG_ARM_LPAE
714 static void __init create_36bit_mapping(struct map_desc *md,
715                                         const struct mem_type *type)
716 {
717         unsigned long addr, length, end;
718         phys_addr_t phys;
719         pgd_t *pgd;
720
721         addr = md->virtual;
722         phys = __pfn_to_phys(md->pfn);
723         length = PAGE_ALIGN(md->length);
724
725         if (!(cpu_architecture() >= CPU_ARCH_ARMv6 || cpu_is_xsc3())) {
726                 printk(KERN_ERR "MM: CPU does not support supersection "
727                        "mapping for 0x%08llx at 0x%08lx\n",
728                        (long long)__pfn_to_phys((u64)md->pfn), addr);
729                 return;
730         }
731
732         /* N.B. ARMv6 supersections are only defined to work with domain 0.
733          *      Since domain assignments can in fact be arbitrary, the
734          *      'domain == 0' check below is required to insure that ARMv6
735          *      supersections are only allocated for domain 0 regardless
736          *      of the actual domain assignments in use.
737          */
738         if (type->domain) {
739                 printk(KERN_ERR "MM: invalid domain in supersection "
740                        "mapping for 0x%08llx at 0x%08lx\n",
741                        (long long)__pfn_to_phys((u64)md->pfn), addr);
742                 return;
743         }
744
745         if ((addr | length | __pfn_to_phys(md->pfn)) & ~SUPERSECTION_MASK) {
746                 printk(KERN_ERR "MM: cannot create mapping for 0x%08llx"
747                        " at 0x%08lx invalid alignment\n",
748                        (long long)__pfn_to_phys((u64)md->pfn), addr);
749                 return;
750         }
751
752         /*
753          * Shift bits [35:32] of address into bits [23:20] of PMD
754          * (See ARMv6 spec).
755          */
756         phys |= (((md->pfn >> (32 - PAGE_SHIFT)) & 0xF) << 20);
757
758         pgd = pgd_offset_k(addr);
759         end = addr + length;
760         do {
761                 pud_t *pud = pud_offset(pgd, addr);
762                 pmd_t *pmd = pmd_offset(pud, addr);
763                 int i;
764
765                 for (i = 0; i < 16; i++)
766                         *pmd++ = __pmd(phys | type->prot_sect | PMD_SECT_SUPER);
767
768                 addr += SUPERSECTION_SIZE;
769                 phys += SUPERSECTION_SIZE;
770                 pgd += SUPERSECTION_SIZE >> PGDIR_SHIFT;
771         } while (addr != end);
772 }
773 #endif  /* !CONFIG_ARM_LPAE */
774
775 /*
776  * Create the page directory entries and any necessary
777  * page tables for the mapping specified by `md'.  We
778  * are able to cope here with varying sizes and address
779  * offsets, and we take full advantage of sections and
780  * supersections.
781  */
782 static void __init create_mapping(struct map_desc *md, bool force_pages)
783 {
784         unsigned long addr, length, end;
785         phys_addr_t phys;
786         const struct mem_type *type;
787         pgd_t *pgd;
788
789         if (md->virtual != vectors_base() && md->virtual < TASK_SIZE) {
790                 printk(KERN_WARNING "BUG: not creating mapping for 0x%08llx"
791                        " at 0x%08lx in user region\n",
792                        (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
793                 return;
794         }
795
796         if ((md->type == MT_DEVICE || md->type == MT_ROM) &&
797             md->virtual >= PAGE_OFFSET &&
798             (md->virtual < VMALLOC_START || md->virtual >= VMALLOC_END)) {
799                 printk(KERN_WARNING "BUG: mapping for 0x%08llx"
800                        " at 0x%08lx out of vmalloc space\n",
801                        (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
802         }
803
804         type = &mem_types[md->type];
805
806 #ifndef CONFIG_ARM_LPAE
807         /*
808          * Catch 36-bit addresses
809          */
810         if (md->pfn >= 0x100000) {
811                 create_36bit_mapping(md, type);
812                 return;
813         }
814 #endif
815
816         addr = md->virtual & PAGE_MASK;
817         phys = __pfn_to_phys(md->pfn);
818         length = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK));
819
820         if (type->prot_l1 == 0 && ((addr | phys | length) & ~SECTION_MASK)) {
821                 printk(KERN_WARNING "BUG: map for 0x%08llx at 0x%08lx can not "
822                        "be mapped using pages, ignoring.\n",
823                        (long long)__pfn_to_phys(md->pfn), addr);
824                 return;
825         }
826
827         pgd = pgd_offset_k(addr);
828         end = addr + length;
829         do {
830                 unsigned long next = pgd_addr_end(addr, end);
831
832                 alloc_init_pud(pgd, addr, next, phys, type, force_pages);
833
834                 phys += next - addr;
835                 addr = next;
836         } while (pgd++, addr != end);
837 }
838
839 /*
840  * Create the architecture specific mappings
841  */
842 void __init iotable_init(struct map_desc *io_desc, int nr)
843 {
844         struct map_desc *md;
845         struct vm_struct *vm;
846         struct static_vm *svm;
847
848         if (!nr)
849                 return;
850
851         svm = early_alloc_aligned(sizeof(*svm) * nr, __alignof__(*svm));
852
853         for (md = io_desc; nr; md++, nr--) {
854                 create_mapping(md, false);
855
856                 vm = &svm->vm;
857                 vm->addr = (void *)(md->virtual & PAGE_MASK);
858                 vm->size = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK));
859                 vm->phys_addr = __pfn_to_phys(md->pfn);
860                 vm->flags = VM_IOREMAP | VM_ARM_STATIC_MAPPING;
861                 vm->flags |= VM_ARM_MTYPE(md->type);
862                 vm->caller = iotable_init;
863                 add_static_vm_early(svm++);
864         }
865 }
866
867 void __init vm_reserve_area_early(unsigned long addr, unsigned long size,
868                                   void *caller)
869 {
870         struct vm_struct *vm;
871         struct static_vm *svm;
872
873         svm = early_alloc_aligned(sizeof(*svm), __alignof__(*svm));
874
875         vm = &svm->vm;
876         vm->addr = (void *)addr;
877         vm->size = size;
878         vm->flags = VM_IOREMAP | VM_ARM_EMPTY_MAPPING;
879         vm->caller = caller;
880         add_static_vm_early(svm);
881 }
882
883 #ifndef CONFIG_ARM_LPAE
884
885 /*
886  * The Linux PMD is made of two consecutive section entries covering 2MB
887  * (see definition in include/asm/pgtable-2level.h).  However a call to
888  * create_mapping() may optimize static mappings by using individual
889  * 1MB section mappings.  This leaves the actual PMD potentially half
890  * initialized if the top or bottom section entry isn't used, leaving it
891  * open to problems if a subsequent ioremap() or vmalloc() tries to use
892  * the virtual space left free by that unused section entry.
893  *
894  * Let's avoid the issue by inserting dummy vm entries covering the unused
895  * PMD halves once the static mappings are in place.
896  */
897
898 static void __init pmd_empty_section_gap(unsigned long addr)
899 {
900         vm_reserve_area_early(addr, SECTION_SIZE, pmd_empty_section_gap);
901 }
902
903 static void __init fill_pmd_gaps(void)
904 {
905         struct static_vm *svm;
906         struct vm_struct *vm;
907         unsigned long addr, next = 0;
908         pmd_t *pmd;
909
910         list_for_each_entry(svm, &static_vmlist, list) {
911                 vm = &svm->vm;
912                 addr = (unsigned long)vm->addr;
913                 if (addr < next)
914                         continue;
915
916                 /*
917                  * Check if this vm starts on an odd section boundary.
918                  * If so and the first section entry for this PMD is free
919                  * then we block the corresponding virtual address.
920                  */
921                 if ((addr & ~PMD_MASK) == SECTION_SIZE) {
922                         pmd = pmd_off_k(addr);
923                         if (pmd_none(*pmd))
924                                 pmd_empty_section_gap(addr & PMD_MASK);
925                 }
926
927                 /*
928                  * Then check if this vm ends on an odd section boundary.
929                  * If so and the second section entry for this PMD is empty
930                  * then we block the corresponding virtual address.
931                  */
932                 addr += vm->size;
933                 if ((addr & ~PMD_MASK) == SECTION_SIZE) {
934                         pmd = pmd_off_k(addr) + 1;
935                         if (pmd_none(*pmd))
936                                 pmd_empty_section_gap(addr);
937                 }
938
939                 /* no need to look at any vm entry until we hit the next PMD */
940                 next = (addr + PMD_SIZE - 1) & PMD_MASK;
941         }
942 }
943
944 #else
945 #define fill_pmd_gaps() do { } while (0)
946 #endif
947
948 #if defined(CONFIG_PCI) && !defined(CONFIG_NEED_MACH_IO_H)
949 static void __init pci_reserve_io(void)
950 {
951         struct static_vm *svm;
952
953         svm = find_static_vm_vaddr((void *)PCI_IO_VIRT_BASE);
954         if (svm)
955                 return;
956
957         vm_reserve_area_early(PCI_IO_VIRT_BASE, SZ_2M, pci_reserve_io);
958 }
959 #else
960 #define pci_reserve_io() do { } while (0)
961 #endif
962
963 #ifdef CONFIG_DEBUG_LL
964 void __init debug_ll_io_init(void)
965 {
966         struct map_desc map;
967
968         debug_ll_addr(&map.pfn, &map.virtual);
969         if (!map.pfn || !map.virtual)
970                 return;
971         map.pfn = __phys_to_pfn(map.pfn);
972         map.virtual &= PAGE_MASK;
973         map.length = PAGE_SIZE;
974         map.type = MT_DEVICE;
975         create_mapping(&map, false);
976 }
977 #endif
978
979 static void * __initdata vmalloc_min =
980         (void *)(VMALLOC_END - (240 << 20) - VMALLOC_OFFSET);
981
982 /*
983  * vmalloc=size forces the vmalloc area to be exactly 'size'
984  * bytes. This can be used to increase (or decrease) the vmalloc
985  * area - the default is 240m.
986  */
987 static int __init early_vmalloc(char *arg)
988 {
989         unsigned long vmalloc_reserve = memparse(arg, NULL);
990
991         if (vmalloc_reserve < SZ_16M) {
992                 vmalloc_reserve = SZ_16M;
993                 printk(KERN_WARNING
994                         "vmalloc area too small, limiting to %luMB\n",
995                         vmalloc_reserve >> 20);
996         }
997
998         if (vmalloc_reserve > VMALLOC_END - (PAGE_OFFSET + SZ_32M)) {
999                 vmalloc_reserve = VMALLOC_END - (PAGE_OFFSET + SZ_32M);
1000                 printk(KERN_WARNING
1001                         "vmalloc area is too big, limiting to %luMB\n",
1002                         vmalloc_reserve >> 20);
1003         }
1004
1005         vmalloc_min = (void *)(VMALLOC_END - vmalloc_reserve);
1006         return 0;
1007 }
1008 early_param("vmalloc", early_vmalloc);
1009
1010 phys_addr_t arm_lowmem_limit __initdata = 0;
1011
1012 void __init sanity_check_meminfo(void)
1013 {
1014         int i, j, highmem = 0;
1015
1016         for (i = 0, j = 0; i < meminfo.nr_banks; i++) {
1017                 struct membank *bank = &meminfo.bank[j];
1018                 *bank = meminfo.bank[i];
1019
1020 #ifdef CONFIG_SPARSEMEM
1021                 if (pfn_to_section_nr(bank_pfn_start(bank)) !=
1022                     pfn_to_section_nr(bank_pfn_end(bank) - 1)) {
1023                         phys_addr_t sz;
1024                         unsigned long start_pfn = bank_pfn_start(bank);
1025                         unsigned long end_pfn = SECTION_ALIGN_UP(start_pfn + 1);
1026                         sz = ((phys_addr_t)(end_pfn - start_pfn) << PAGE_SHIFT);
1027
1028                         if (meminfo.nr_banks >= NR_BANKS) {
1029                                 pr_crit("NR_BANKS too low, ignoring %lld bytes of memory\n",
1030                                         (unsigned long long)(bank->size - sz));
1031                         } else {
1032                                 memmove(bank + 1, bank,
1033                                         (meminfo.nr_banks - i) * sizeof(*bank));
1034                                 meminfo.nr_banks++;
1035                                 bank[1].size -= sz;
1036                                 bank[1].start = __pfn_to_phys(end_pfn);
1037                         }
1038                         bank->size = sz;
1039                 }
1040 #endif
1041
1042                 if (bank->start > ULONG_MAX)
1043                         highmem = 1;
1044
1045 #ifdef CONFIG_HIGHMEM
1046                 if (__va(bank->start) >= vmalloc_min ||
1047                     __va(bank->start) < (void *)PAGE_OFFSET)
1048                         highmem = 1;
1049
1050                 bank->highmem = highmem;
1051
1052                 /*
1053                  * Split those memory banks which are partially overlapping
1054                  * the vmalloc area greatly simplifying things later.
1055                  */
1056                 if (!highmem && __va(bank->start) < vmalloc_min &&
1057                     bank->size > vmalloc_min - __va(bank->start)) {
1058                         if (meminfo.nr_banks >= NR_BANKS) {
1059                                 printk(KERN_CRIT "NR_BANKS too low, "
1060                                                  "ignoring high memory\n");
1061                         } else {
1062                                 memmove(bank + 1, bank,
1063                                         (meminfo.nr_banks - i) * sizeof(*bank));
1064                                 meminfo.nr_banks++;
1065                                 i++;
1066                                 bank[1].size -= vmalloc_min - __va(bank->start);
1067                                 bank[1].start = __pa(vmalloc_min - 1) + 1;
1068                                 bank[1].highmem = highmem = 1;
1069                                 j++;
1070                         }
1071                         bank->size = vmalloc_min - __va(bank->start);
1072                 }
1073 #else
1074                 bank->highmem = highmem;
1075
1076                 /*
1077                  * Highmem banks not allowed with !CONFIG_HIGHMEM.
1078                  */
1079                 if (highmem) {
1080                         printk(KERN_NOTICE "Ignoring RAM at %.8llx-%.8llx "
1081                                "(!CONFIG_HIGHMEM).\n",
1082                                (unsigned long long)bank->start,
1083                                (unsigned long long)bank->start + bank->size - 1);
1084                         continue;
1085                 }
1086
1087                 /*
1088                  * Check whether this memory bank would entirely overlap
1089                  * the vmalloc area.
1090                  */
1091                 if (__va(bank->start) >= vmalloc_min ||
1092                     __va(bank->start) < (void *)PAGE_OFFSET) {
1093                         printk(KERN_NOTICE "Ignoring RAM at %.8llx-%.8llx "
1094                                "(vmalloc region overlap).\n",
1095                                (unsigned long long)bank->start,
1096                                (unsigned long long)bank->start + bank->size - 1);
1097                         continue;
1098                 }
1099
1100                 /*
1101                  * Check whether this memory bank would partially overlap
1102                  * the vmalloc area.
1103                  */
1104                 if (__va(bank->start + bank->size - 1) >= vmalloc_min ||
1105                     __va(bank->start + bank->size - 1) <= __va(bank->start)) {
1106                         unsigned long newsize = vmalloc_min - __va(bank->start);
1107                         printk(KERN_NOTICE "Truncating RAM at %.8llx-%.8llx "
1108                                "to -%.8llx (vmalloc region overlap).\n",
1109                                (unsigned long long)bank->start,
1110                                (unsigned long long)bank->start + bank->size - 1,
1111                                (unsigned long long)bank->start + newsize - 1);
1112                         bank->size = newsize;
1113                 }
1114 #endif
1115                 if (!bank->highmem && bank->start + bank->size > arm_lowmem_limit)
1116                         arm_lowmem_limit = bank->start + bank->size;
1117
1118                 j++;
1119         }
1120 #ifdef CONFIG_HIGHMEM
1121         if (highmem) {
1122                 const char *reason = NULL;
1123
1124                 if (cache_is_vipt_aliasing()) {
1125                         /*
1126                          * Interactions between kmap and other mappings
1127                          * make highmem support with aliasing VIPT caches
1128                          * rather difficult.
1129                          */
1130                         reason = "with VIPT aliasing cache";
1131                 }
1132                 if (reason) {
1133                         printk(KERN_CRIT "HIGHMEM is not supported %s, ignoring high memory\n",
1134                                 reason);
1135                         while (j > 0 && meminfo.bank[j - 1].highmem)
1136                                 j--;
1137                 }
1138         }
1139 #endif
1140         meminfo.nr_banks = j;
1141         high_memory = __va(arm_lowmem_limit - 1) + 1;
1142         memblock_set_current_limit(arm_lowmem_limit);
1143 }
1144
1145 static inline void prepare_page_table(void)
1146 {
1147         unsigned long addr;
1148         phys_addr_t end;
1149
1150         /*
1151          * Clear out all the mappings below the kernel image.
1152          */
1153         for (addr = 0; addr < MODULES_VADDR; addr += PMD_SIZE)
1154                 pmd_clear(pmd_off_k(addr));
1155
1156 #ifdef CONFIG_XIP_KERNEL
1157         /* The XIP kernel is mapped in the module area -- skip over it */
1158         addr = ((unsigned long)_etext + PMD_SIZE - 1) & PMD_MASK;
1159 #endif
1160         for ( ; addr < PAGE_OFFSET; addr += PMD_SIZE)
1161                 pmd_clear(pmd_off_k(addr));
1162
1163         /*
1164          * Find the end of the first block of lowmem.
1165          */
1166         end = memblock.memory.regions[0].base + memblock.memory.regions[0].size;
1167         if (end >= arm_lowmem_limit)
1168                 end = arm_lowmem_limit;
1169
1170         /*
1171          * Clear out all the kernel space mappings, except for the first
1172          * memory bank, up to the vmalloc region.
1173          */
1174         for (addr = __phys_to_virt(end);
1175              addr < VMALLOC_START; addr += PMD_SIZE)
1176                 pmd_clear(pmd_off_k(addr));
1177 }
1178
1179 #ifdef CONFIG_ARM_LPAE
1180 /* the first page is reserved for pgd */
1181 #define SWAPPER_PG_DIR_SIZE     (PAGE_SIZE + \
1182                                  PTRS_PER_PGD * PTRS_PER_PMD * sizeof(pmd_t))
1183 #else
1184 #define SWAPPER_PG_DIR_SIZE     (PTRS_PER_PGD * sizeof(pgd_t))
1185 #endif
1186
1187 /*
1188  * Reserve the special regions of memory
1189  */
1190 void __init arm_mm_memblock_reserve(void)
1191 {
1192         /*
1193          * Reserve the page tables.  These are already in use,
1194          * and can only be in node 0.
1195          */
1196         memblock_reserve(__pa(swapper_pg_dir), SWAPPER_PG_DIR_SIZE);
1197
1198 #ifdef CONFIG_SA1111
1199         /*
1200          * Because of the SA1111 DMA bug, we want to preserve our
1201          * precious DMA-able memory...
1202          */
1203         memblock_reserve(PHYS_OFFSET, __pa(swapper_pg_dir) - PHYS_OFFSET);
1204 #endif
1205 }
1206
1207 /*
1208  * Set up the device mappings.  Since we clear out the page tables for all
1209  * mappings above VMALLOC_START, we will remove any debug device mappings.
1210  * This means you have to be careful how you debug this function, or any
1211  * called function.  This means you can't use any function or debugging
1212  * method which may touch any device, otherwise the kernel _will_ crash.
1213  */
1214 static void __init devicemaps_init(struct machine_desc *mdesc)
1215 {
1216         struct map_desc map;
1217         unsigned long addr;
1218         void *vectors;
1219
1220         /*
1221          * Allocate the vector page early.
1222          */
1223         vectors = early_alloc(PAGE_SIZE * 2);
1224
1225         early_trap_init(vectors);
1226
1227         for (addr = VMALLOC_START; addr; addr += PMD_SIZE)
1228                 pmd_clear(pmd_off_k(addr));
1229
1230         /*
1231          * Map the kernel if it is XIP.
1232          * It is always first in the modulearea.
1233          */
1234 #ifdef CONFIG_XIP_KERNEL
1235         map.pfn = __phys_to_pfn(CONFIG_XIP_PHYS_ADDR & SECTION_MASK);
1236         map.virtual = MODULES_VADDR;
1237         map.length = ((unsigned long)_etext - map.virtual + ~SECTION_MASK) & SECTION_MASK;
1238         map.type = MT_ROM;
1239         create_mapping(&map, false);
1240 #endif
1241
1242         /*
1243          * Map the cache flushing regions.
1244          */
1245 #ifdef FLUSH_BASE
1246         map.pfn = __phys_to_pfn(FLUSH_BASE_PHYS);
1247         map.virtual = FLUSH_BASE;
1248         map.length = SZ_1M;
1249         map.type = MT_CACHECLEAN;
1250         create_mapping(&map, false);
1251 #endif
1252 #ifdef FLUSH_BASE_MINICACHE
1253         map.pfn = __phys_to_pfn(FLUSH_BASE_PHYS + SZ_1M);
1254         map.virtual = FLUSH_BASE_MINICACHE;
1255         map.length = SZ_1M;
1256         map.type = MT_MINICLEAN;
1257         create_mapping(&map, false);
1258 #endif
1259
1260         /*
1261          * Create a mapping for the machine vectors at the high-vectors
1262          * location (0xffff0000).  If we aren't using high-vectors, also
1263          * create a mapping at the low-vectors virtual address.
1264          */
1265         map.pfn = __phys_to_pfn(virt_to_phys(vectors));
1266         map.virtual = 0xffff0000;
1267         map.length = PAGE_SIZE;
1268 #ifdef CONFIG_KUSER_HELPERS
1269         map.type = MT_HIGH_VECTORS;
1270 #else
1271         map.type = MT_LOW_VECTORS;
1272 #endif
1273         create_mapping(&map, false);
1274
1275         if (!vectors_high()) {
1276                 map.virtual = 0;
1277                 map.length = PAGE_SIZE * 2;
1278                 map.type = MT_LOW_VECTORS;
1279                 create_mapping(&map, false);
1280         }
1281
1282         /* Now create a kernel read-only mapping */
1283         map.pfn += 1;
1284         map.virtual = 0xffff0000 + PAGE_SIZE;
1285         map.length = PAGE_SIZE;
1286         map.type = MT_LOW_VECTORS;
1287         create_mapping(&map, false);
1288
1289         /*
1290          * Ask the machine support to map in the statically mapped devices.
1291          */
1292         if (mdesc->map_io)
1293                 mdesc->map_io();
1294         fill_pmd_gaps();
1295
1296         /* Reserve fixed i/o space in VMALLOC region */
1297         pci_reserve_io();
1298
1299         /*
1300          * Finally flush the caches and tlb to ensure that we're in a
1301          * consistent state wrt the writebuffer.  This also ensures that
1302          * any write-allocated cache lines in the vector page are written
1303          * back.  After this point, we can start to touch devices again.
1304          */
1305         local_flush_tlb_all();
1306         flush_cache_all();
1307 }
1308
1309 static void __init kmap_init(void)
1310 {
1311 #ifdef CONFIG_HIGHMEM
1312         pkmap_page_table = early_pte_alloc_and_install(pmd_off_k(PKMAP_BASE),
1313                 PKMAP_BASE, _PAGE_KERNEL_TABLE);
1314 #endif
1315 }
1316
1317
1318 static void __init map_lowmem(void)
1319 {
1320         struct memblock_region *reg;
1321         phys_addr_t start;
1322         phys_addr_t end;
1323         struct map_desc map;
1324
1325         /* Map all the lowmem memory banks. */
1326         for_each_memblock(memory, reg) {
1327                 start = reg->base;
1328                 end = start + reg->size;
1329
1330                 if (end > arm_lowmem_limit)
1331                         end = arm_lowmem_limit;
1332                 if (start >= end)
1333                         break;
1334
1335                 map.pfn = __phys_to_pfn(start);
1336                 map.virtual = __phys_to_virt(start);
1337                 map.length = end - start;
1338                 map.type = MT_MEMORY;
1339
1340                 create_mapping(&map, false);
1341         }
1342
1343 #ifdef CONFIG_DEBUG_RODATA
1344         start = __pa(_stext) & PMD_MASK;
1345         end = ALIGN(__pa(__end_rodata), PMD_SIZE);
1346
1347         map.pfn = __phys_to_pfn(start);
1348         map.virtual = __phys_to_virt(start);
1349         map.length = end - start;
1350         map.type = MT_MEMORY;
1351
1352         create_mapping(&map, true);
1353 #endif
1354 }
1355
1356 /*
1357  * paging_init() sets up the page tables, initialises the zone memory
1358  * maps, and sets up the zero page, bad page and bad page tables.
1359  */
1360 void __init paging_init(struct machine_desc *mdesc)
1361 {
1362         void *zero_page;
1363
1364         memblock_set_current_limit(arm_lowmem_limit);
1365
1366         build_mem_type_table();
1367         prepare_page_table();
1368         map_lowmem();
1369         dma_contiguous_remap();
1370         devicemaps_init(mdesc);
1371         kmap_init();
1372         tcm_init();
1373
1374         top_pmd = pmd_off_k(0xffff0000);
1375
1376         /* allocate the zero page. */
1377         zero_page = early_alloc(PAGE_SIZE);
1378
1379         bootmem_init();
1380
1381         empty_zero_page = virt_to_page(zero_page);
1382         __flush_dcache_page(NULL, empty_zero_page);
1383 }