2 * linux/arch/arm/mm/mmu.c
4 * Copyright (C) 1995-2005 Russell King
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.
10 #include <linux/module.h>
11 #include <linux/kernel.h>
12 #include <linux/errno.h>
13 #include <linux/init.h>
14 #include <linux/bootmem.h>
15 #include <linux/mman.h>
16 #include <linux/nodemask.h>
18 #include <asm/mach-types.h>
19 #include <asm/setup.h>
20 #include <asm/sizes.h>
23 #include <asm/mach/arch.h>
24 #include <asm/mach/map.h>
28 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
30 extern void _stext, _etext, __data_start, _end;
31 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
34 * empty_zero_page is a special page that is used for
35 * zero-initialized data and COW.
37 struct page *empty_zero_page;
38 EXPORT_SYMBOL(empty_zero_page);
41 * The pmd table for the upper-most set of pages.
45 #define CPOLICY_UNCACHED 0
46 #define CPOLICY_BUFFERED 1
47 #define CPOLICY_WRITETHROUGH 2
48 #define CPOLICY_WRITEBACK 3
49 #define CPOLICY_WRITEALLOC 4
51 static unsigned int cachepolicy __initdata = CPOLICY_WRITEBACK;
52 static unsigned int ecc_mask __initdata = 0;
54 pgprot_t pgprot_kernel;
56 EXPORT_SYMBOL(pgprot_user);
57 EXPORT_SYMBOL(pgprot_kernel);
60 const char policy[16];
66 static struct cachepolicy cache_policies[] __initdata = {
70 .pmd = PMD_SECT_UNCACHED,
71 .pte = L_PTE_MT_UNCACHED,
75 .pmd = PMD_SECT_BUFFERED,
76 .pte = L_PTE_MT_BUFFERABLE,
78 .policy = "writethrough",
81 .pte = L_PTE_MT_WRITETHROUGH,
83 .policy = "writeback",
86 .pte = L_PTE_MT_WRITEBACK,
88 .policy = "writealloc",
91 .pte = L_PTE_MT_WRITEALLOC,
96 * These are useful for identifying cache coherency
97 * problems by allowing the cache or the cache and
98 * writebuffer to be turned off. (Note: the write
99 * buffer should not be on and the cache off).
101 static void __init early_cachepolicy(char **p)
105 for (i = 0; i < ARRAY_SIZE(cache_policies); i++) {
106 int len = strlen(cache_policies[i].policy);
108 if (memcmp(*p, cache_policies[i].policy, len) == 0) {
110 cr_alignment &= ~cache_policies[i].cr_mask;
111 cr_no_alignment &= ~cache_policies[i].cr_mask;
116 if (i == ARRAY_SIZE(cache_policies))
117 printk(KERN_ERR "ERROR: unknown or unsupported cache policy\n");
118 if (cpu_architecture() >= CPU_ARCH_ARMv6) {
119 printk(KERN_WARNING "Only cachepolicy=writeback supported on ARMv6 and later\n");
120 cachepolicy = CPOLICY_WRITEBACK;
123 set_cr(cr_alignment);
125 __early_param("cachepolicy=", early_cachepolicy);
127 static void __init early_nocache(char **__unused)
129 char *p = "buffered";
130 printk(KERN_WARNING "nocache is deprecated; use cachepolicy=%s\n", p);
131 early_cachepolicy(&p);
133 __early_param("nocache", early_nocache);
135 static void __init early_nowrite(char **__unused)
137 char *p = "uncached";
138 printk(KERN_WARNING "nowb is deprecated; use cachepolicy=%s\n", p);
139 early_cachepolicy(&p);
141 __early_param("nowb", early_nowrite);
143 static void __init early_ecc(char **p)
145 if (memcmp(*p, "on", 2) == 0) {
146 ecc_mask = PMD_PROTECTION;
148 } else if (memcmp(*p, "off", 3) == 0) {
153 __early_param("ecc=", early_ecc);
155 static int __init noalign_setup(char *__unused)
157 cr_alignment &= ~CR_A;
158 cr_no_alignment &= ~CR_A;
159 set_cr(cr_alignment);
162 __setup("noalign", noalign_setup);
165 void adjust_cr(unsigned long mask, unsigned long set)
173 local_irq_save(flags);
175 cr_no_alignment = (cr_no_alignment & ~mask) | set;
176 cr_alignment = (cr_alignment & ~mask) | set;
178 set_cr((get_cr() & ~mask) | set);
180 local_irq_restore(flags);
184 #define PROT_PTE_DEVICE L_PTE_PRESENT|L_PTE_YOUNG|L_PTE_DIRTY|L_PTE_WRITE
185 #define PROT_SECT_DEVICE PMD_TYPE_SECT|PMD_SECT_XN|PMD_SECT_AP_WRITE
187 static struct mem_type mem_types[] = {
188 [MT_DEVICE] = { /* Strongly ordered / ARMv6 shared device */
189 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_SHARED |
191 .prot_l1 = PMD_TYPE_TABLE,
192 .prot_sect = PROT_SECT_DEVICE | PMD_SECT_UNCACHED,
195 [MT_DEVICE_NONSHARED] = { /* ARMv6 non-shared device */
196 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_NONSHARED,
197 .prot_l1 = PMD_TYPE_TABLE,
198 .prot_sect = PROT_SECT_DEVICE | PMD_SECT_TEX(2),
201 [MT_DEVICE_CACHED] = { /* ioremap_cached */
202 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_CACHED,
203 .prot_l1 = PMD_TYPE_TABLE,
204 .prot_sect = PROT_SECT_DEVICE | PMD_SECT_WB,
207 [MT_DEVICE_IXP2000] = { /* IXP2400 requires XCB=101 for on-chip I/O */
208 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_IXP2000,
209 .prot_l1 = PMD_TYPE_TABLE,
210 .prot_sect = PROT_SECT_DEVICE | PMD_SECT_BUFFERABLE |
214 [MT_DEVICE_WC] = { /* ioremap_wc */
215 .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_WC,
216 .prot_l1 = PMD_TYPE_TABLE,
217 .prot_sect = PROT_SECT_DEVICE | PMD_SECT_BUFFERABLE,
221 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
222 .domain = DOMAIN_KERNEL,
225 .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN | PMD_SECT_MINICACHE,
226 .domain = DOMAIN_KERNEL,
229 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
231 .prot_l1 = PMD_TYPE_TABLE,
232 .domain = DOMAIN_USER,
234 [MT_HIGH_VECTORS] = {
235 .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
236 L_PTE_USER | L_PTE_EXEC,
237 .prot_l1 = PMD_TYPE_TABLE,
238 .domain = DOMAIN_USER,
241 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
242 .domain = DOMAIN_KERNEL,
245 .prot_sect = PMD_TYPE_SECT,
246 .domain = DOMAIN_KERNEL,
249 .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_SECT_UNCACHED,
250 .domain = DOMAIN_KERNEL,
254 const struct mem_type *get_mem_type(unsigned int type)
256 return type < ARRAY_SIZE(mem_types) ? &mem_types[type] : NULL;
260 * Adjust the PMD section entries according to the CPU in use.
262 static void __init build_mem_type_table(void)
264 struct cachepolicy *cp;
265 unsigned int cr = get_cr();
266 unsigned int user_pgprot, kern_pgprot, vecs_pgprot;
267 int cpu_arch = cpu_architecture();
270 if (cpu_arch < CPU_ARCH_ARMv6) {
271 #if defined(CONFIG_CPU_DCACHE_DISABLE)
272 if (cachepolicy > CPOLICY_BUFFERED)
273 cachepolicy = CPOLICY_BUFFERED;
274 #elif defined(CONFIG_CPU_DCACHE_WRITETHROUGH)
275 if (cachepolicy > CPOLICY_WRITETHROUGH)
276 cachepolicy = CPOLICY_WRITETHROUGH;
279 if (cpu_arch < CPU_ARCH_ARMv5) {
280 if (cachepolicy >= CPOLICY_WRITEALLOC)
281 cachepolicy = CPOLICY_WRITEBACK;
285 cachepolicy = CPOLICY_WRITEALLOC;
289 * On non-Xscale3 ARMv5-and-older systems, use CB=01
290 * (Uncached/Buffered) for ioremap_wc() mappings. On XScale3
291 * and ARMv6+, use TEXCB=00100 mappings (Inner/Outer Uncacheable
292 * in xsc3 parlance, Uncached Normal in ARMv6 parlance).
294 if (cpu_is_xsc3() || cpu_arch >= CPU_ARCH_ARMv6) {
295 mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1);
296 mem_types[MT_DEVICE_WC].prot_sect &= ~PMD_SECT_BUFFERABLE;
300 * ARMv5 and lower, bit 4 must be set for page tables.
301 * (was: cache "update-able on write" bit on ARM610)
302 * However, Xscale cores require this bit to be cleared.
304 if (cpu_is_xscale()) {
305 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
306 mem_types[i].prot_sect &= ~PMD_BIT4;
307 mem_types[i].prot_l1 &= ~PMD_BIT4;
309 } else if (cpu_arch < CPU_ARCH_ARMv6) {
310 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
311 if (mem_types[i].prot_l1)
312 mem_types[i].prot_l1 |= PMD_BIT4;
313 if (mem_types[i].prot_sect)
314 mem_types[i].prot_sect |= PMD_BIT4;
318 cp = &cache_policies[cachepolicy];
319 vecs_pgprot = kern_pgprot = user_pgprot = cp->pte;
323 * Only use write-through for non-SMP systems
325 if (cpu_arch >= CPU_ARCH_ARMv5 && cachepolicy > CPOLICY_WRITETHROUGH)
326 vecs_pgprot = cache_policies[CPOLICY_WRITETHROUGH].pte;
330 * Enable CPU-specific coherency if supported.
331 * (Only available on XSC3 at the moment.)
333 if (arch_is_coherent()) {
335 mem_types[MT_MEMORY].prot_sect |= PMD_SECT_S;
336 mem_types[MT_MEMORY].prot_pte |= L_PTE_SHARED;
341 * ARMv6 and above have extended page tables.
343 if (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP)) {
345 * Mark cache clean areas and XIP ROM read only
346 * from SVC mode and no access from userspace.
348 mem_types[MT_ROM].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
349 mem_types[MT_MINICLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
350 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
353 * Mark the device area as "shared device"
355 mem_types[MT_DEVICE].prot_sect |= PMD_SECT_BUFFERED;
359 * Mark memory with the "shared" attribute for SMP systems
361 user_pgprot |= L_PTE_SHARED;
362 kern_pgprot |= L_PTE_SHARED;
363 vecs_pgprot |= L_PTE_SHARED;
364 mem_types[MT_MEMORY].prot_sect |= PMD_SECT_S;
368 for (i = 0; i < 16; i++) {
369 unsigned long v = pgprot_val(protection_map[i]);
370 protection_map[i] = __pgprot(v | user_pgprot);
373 mem_types[MT_LOW_VECTORS].prot_pte |= vecs_pgprot;
374 mem_types[MT_HIGH_VECTORS].prot_pte |= vecs_pgprot;
376 if (cpu_arch < CPU_ARCH_ARMv5)
377 mem_types[MT_MINICLEAN].prot_sect &= ~PMD_SECT_TEX(1);
379 pgprot_user = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | user_pgprot);
380 pgprot_kernel = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG |
381 L_PTE_DIRTY | L_PTE_WRITE |
382 L_PTE_EXEC | kern_pgprot);
384 mem_types[MT_LOW_VECTORS].prot_l1 |= ecc_mask;
385 mem_types[MT_HIGH_VECTORS].prot_l1 |= ecc_mask;
386 mem_types[MT_MEMORY].prot_sect |= ecc_mask | cp->pmd;
387 mem_types[MT_ROM].prot_sect |= cp->pmd;
391 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WT;
395 mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WB;
398 printk("Memory policy: ECC %sabled, Data cache %s\n",
399 ecc_mask ? "en" : "dis", cp->policy);
401 for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
402 struct mem_type *t = &mem_types[i];
404 t->prot_l1 |= PMD_DOMAIN(t->domain);
406 t->prot_sect |= PMD_DOMAIN(t->domain);
410 #define vectors_base() (vectors_high() ? 0xffff0000 : 0)
412 static void __init alloc_init_pte(pmd_t *pmd, unsigned long addr,
413 unsigned long end, unsigned long pfn,
414 const struct mem_type *type)
418 if (pmd_none(*pmd)) {
419 pte = alloc_bootmem_low_pages(2 * PTRS_PER_PTE * sizeof(pte_t));
420 __pmd_populate(pmd, __pa(pte) | type->prot_l1);
423 pte = pte_offset_kernel(pmd, addr);
425 set_pte_ext(pte, pfn_pte(pfn, __pgprot(type->prot_pte)),
428 } while (pte++, addr += PAGE_SIZE, addr != end);
431 static void __init alloc_init_section(pgd_t *pgd, unsigned long addr,
432 unsigned long end, unsigned long phys,
433 const struct mem_type *type)
435 pmd_t *pmd = pmd_offset(pgd, addr);
438 * Try a section mapping - end, addr and phys must all be aligned
439 * to a section boundary. Note that PMDs refer to the individual
440 * L1 entries, whereas PGDs refer to a group of L1 entries making
441 * up one logical pointer to an L2 table.
443 if (((addr | end | phys) & ~SECTION_MASK) == 0) {
446 if (addr & SECTION_SIZE)
450 *pmd = __pmd(phys | type->prot_sect);
451 phys += SECTION_SIZE;
452 } while (pmd++, addr += SECTION_SIZE, addr != end);
457 * No need to loop; pte's aren't interested in the
458 * individual L1 entries.
460 alloc_init_pte(pmd, addr, end, __phys_to_pfn(phys), type);
464 static void __init create_36bit_mapping(struct map_desc *md,
465 const struct mem_type *type)
467 unsigned long phys, addr, length, end;
471 phys = (unsigned long)__pfn_to_phys(md->pfn);
472 length = PAGE_ALIGN(md->length);
474 if (!(cpu_architecture() >= CPU_ARCH_ARMv6 || cpu_is_xsc3())) {
475 printk(KERN_ERR "MM: CPU does not support supersection "
476 "mapping for 0x%08llx at 0x%08lx\n",
477 __pfn_to_phys((u64)md->pfn), addr);
481 /* N.B. ARMv6 supersections are only defined to work with domain 0.
482 * Since domain assignments can in fact be arbitrary, the
483 * 'domain == 0' check below is required to insure that ARMv6
484 * supersections are only allocated for domain 0 regardless
485 * of the actual domain assignments in use.
488 printk(KERN_ERR "MM: invalid domain in supersection "
489 "mapping for 0x%08llx at 0x%08lx\n",
490 __pfn_to_phys((u64)md->pfn), addr);
494 if ((addr | length | __pfn_to_phys(md->pfn)) & ~SUPERSECTION_MASK) {
495 printk(KERN_ERR "MM: cannot create mapping for "
496 "0x%08llx at 0x%08lx invalid alignment\n",
497 __pfn_to_phys((u64)md->pfn), addr);
502 * Shift bits [35:32] of address into bits [23:20] of PMD
505 phys |= (((md->pfn >> (32 - PAGE_SHIFT)) & 0xF) << 20);
507 pgd = pgd_offset_k(addr);
510 pmd_t *pmd = pmd_offset(pgd, addr);
513 for (i = 0; i < 16; i++)
514 *pmd++ = __pmd(phys | type->prot_sect | PMD_SECT_SUPER);
516 addr += SUPERSECTION_SIZE;
517 phys += SUPERSECTION_SIZE;
518 pgd += SUPERSECTION_SIZE >> PGDIR_SHIFT;
519 } while (addr != end);
523 * Create the page directory entries and any necessary
524 * page tables for the mapping specified by `md'. We
525 * are able to cope here with varying sizes and address
526 * offsets, and we take full advantage of sections and
529 void __init create_mapping(struct map_desc *md)
531 unsigned long phys, addr, length, end;
532 const struct mem_type *type;
535 if (md->virtual != vectors_base() && md->virtual < TASK_SIZE) {
536 printk(KERN_WARNING "BUG: not creating mapping for "
537 "0x%08llx at 0x%08lx in user region\n",
538 __pfn_to_phys((u64)md->pfn), md->virtual);
542 if ((md->type == MT_DEVICE || md->type == MT_ROM) &&
543 md->virtual >= PAGE_OFFSET && md->virtual < VMALLOC_END) {
544 printk(KERN_WARNING "BUG: mapping for 0x%08llx at 0x%08lx "
545 "overlaps vmalloc space\n",
546 __pfn_to_phys((u64)md->pfn), md->virtual);
549 type = &mem_types[md->type];
552 * Catch 36-bit addresses
554 if (md->pfn >= 0x100000) {
555 create_36bit_mapping(md, type);
559 addr = md->virtual & PAGE_MASK;
560 phys = (unsigned long)__pfn_to_phys(md->pfn);
561 length = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK));
563 if (type->prot_l1 == 0 && ((addr | phys | length) & ~SECTION_MASK)) {
564 printk(KERN_WARNING "BUG: map for 0x%08lx at 0x%08lx can not "
565 "be mapped using pages, ignoring.\n",
566 __pfn_to_phys(md->pfn), addr);
570 pgd = pgd_offset_k(addr);
573 unsigned long next = pgd_addr_end(addr, end);
575 alloc_init_section(pgd, addr, next, phys, type);
579 } while (pgd++, addr != end);
583 * Create the architecture specific mappings
585 void __init iotable_init(struct map_desc *io_desc, int nr)
589 for (i = 0; i < nr; i++)
590 create_mapping(io_desc + i);
593 static int __init check_membank_valid(struct membank *mb)
596 * Check whether this memory region has non-zero size.
602 * Check whether this memory region would entirely overlap
605 if (phys_to_virt(mb->start) >= VMALLOC_MIN) {
606 printk(KERN_NOTICE "Ignoring RAM at %.8lx-%.8lx "
607 "(vmalloc region overlap).\n",
608 mb->start, mb->start + mb->size - 1);
613 * Check whether this memory region would partially overlap
616 if (phys_to_virt(mb->start + mb->size) < phys_to_virt(mb->start) ||
617 phys_to_virt(mb->start + mb->size) > VMALLOC_MIN) {
618 unsigned long newsize = VMALLOC_MIN - phys_to_virt(mb->start);
620 printk(KERN_NOTICE "Truncating RAM at %.8lx-%.8lx "
621 "to -%.8lx (vmalloc region overlap).\n",
622 mb->start, mb->start + mb->size - 1,
623 mb->start + newsize - 1);
630 static void __init sanity_check_meminfo(struct meminfo *mi)
635 for (i = 0, j = 0; i < mi->nr_banks; i++) {
636 if (check_membank_valid(&mi->bank[i]))
637 mi->bank[j++] = mi->bank[i];
642 static inline void prepare_page_table(struct meminfo *mi)
647 * Clear out all the mappings below the kernel image.
649 for (addr = 0; addr < MODULE_START; addr += PGDIR_SIZE)
650 pmd_clear(pmd_off_k(addr));
652 #ifdef CONFIG_XIP_KERNEL
653 /* The XIP kernel is mapped in the module area -- skip over it */
654 addr = ((unsigned long)&_etext + PGDIR_SIZE - 1) & PGDIR_MASK;
656 for ( ; addr < PAGE_OFFSET; addr += PGDIR_SIZE)
657 pmd_clear(pmd_off_k(addr));
660 * Clear out all the kernel space mappings, except for the first
661 * memory bank, up to the end of the vmalloc region.
663 for (addr = __phys_to_virt(mi->bank[0].start + mi->bank[0].size);
664 addr < VMALLOC_END; addr += PGDIR_SIZE)
665 pmd_clear(pmd_off_k(addr));
669 * Reserve the various regions of node 0
671 void __init reserve_node_zero(pg_data_t *pgdat)
673 unsigned long res_size = 0;
676 * Register the kernel text and data with bootmem.
677 * Note that this can only be in node 0.
679 #ifdef CONFIG_XIP_KERNEL
680 reserve_bootmem_node(pgdat, __pa(&__data_start), &_end - &__data_start,
683 reserve_bootmem_node(pgdat, __pa(&_stext), &_end - &_stext,
688 * Reserve the page tables. These are already in use,
689 * and can only be in node 0.
691 reserve_bootmem_node(pgdat, __pa(swapper_pg_dir),
692 PTRS_PER_PGD * sizeof(pgd_t), BOOTMEM_DEFAULT);
695 * Hmm... This should go elsewhere, but we really really need to
696 * stop things allocating the low memory; ideally we need a better
697 * implementation of GFP_DMA which does not assume that DMA-able
698 * memory starts at zero.
700 if (machine_is_integrator() || machine_is_cintegrator())
701 res_size = __pa(swapper_pg_dir) - PHYS_OFFSET;
704 * These should likewise go elsewhere. They pre-reserve the
705 * screen memory region at the start of main system memory.
707 if (machine_is_edb7211())
708 res_size = 0x00020000;
709 if (machine_is_p720t())
710 res_size = 0x00014000;
712 /* H1940 and RX3715 need to reserve this for suspend */
714 if (machine_is_h1940() || machine_is_rx3715()) {
715 reserve_bootmem_node(pgdat, 0x30003000, 0x1000,
717 reserve_bootmem_node(pgdat, 0x30081000, 0x1000,
723 * Because of the SA1111 DMA bug, we want to preserve our
724 * precious DMA-able memory...
726 res_size = __pa(swapper_pg_dir) - PHYS_OFFSET;
729 reserve_bootmem_node(pgdat, PHYS_OFFSET, res_size,
734 * Set up device the mappings. Since we clear out the page tables for all
735 * mappings above VMALLOC_END, we will remove any debug device mappings.
736 * This means you have to be careful how you debug this function, or any
737 * called function. This means you can't use any function or debugging
738 * method which may touch any device, otherwise the kernel _will_ crash.
740 static void __init devicemaps_init(struct machine_desc *mdesc)
747 * Allocate the vector page early.
749 vectors = alloc_bootmem_low_pages(PAGE_SIZE);
752 for (addr = VMALLOC_END; addr; addr += PGDIR_SIZE)
753 pmd_clear(pmd_off_k(addr));
756 * Map the kernel if it is XIP.
757 * It is always first in the modulearea.
759 #ifdef CONFIG_XIP_KERNEL
760 map.pfn = __phys_to_pfn(CONFIG_XIP_PHYS_ADDR & SECTION_MASK);
761 map.virtual = MODULE_START;
762 map.length = ((unsigned long)&_etext - map.virtual + ~SECTION_MASK) & SECTION_MASK;
764 create_mapping(&map);
768 * Map the cache flushing regions.
771 map.pfn = __phys_to_pfn(FLUSH_BASE_PHYS);
772 map.virtual = FLUSH_BASE;
774 map.type = MT_CACHECLEAN;
775 create_mapping(&map);
777 #ifdef FLUSH_BASE_MINICACHE
778 map.pfn = __phys_to_pfn(FLUSH_BASE_PHYS + SZ_1M);
779 map.virtual = FLUSH_BASE_MINICACHE;
781 map.type = MT_MINICLEAN;
782 create_mapping(&map);
786 * Create a mapping for the machine vectors at the high-vectors
787 * location (0xffff0000). If we aren't using high-vectors, also
788 * create a mapping at the low-vectors virtual address.
790 map.pfn = __phys_to_pfn(virt_to_phys(vectors));
791 map.virtual = 0xffff0000;
792 map.length = PAGE_SIZE;
793 map.type = MT_HIGH_VECTORS;
794 create_mapping(&map);
796 if (!vectors_high()) {
798 map.type = MT_LOW_VECTORS;
799 create_mapping(&map);
803 * Ask the machine support to map in the statically mapped devices.
809 * Finally flush the caches and tlb to ensure that we're in a
810 * consistent state wrt the writebuffer. This also ensures that
811 * any write-allocated cache lines in the vector page are written
812 * back. After this point, we can start to touch devices again.
814 local_flush_tlb_all();
819 * paging_init() sets up the page tables, initialises the zone memory
820 * maps, and sets up the zero page, bad page and bad page tables.
822 void __init paging_init(struct meminfo *mi, struct machine_desc *mdesc)
826 build_mem_type_table();
827 sanity_check_meminfo(mi);
828 prepare_page_table(mi);
830 devicemaps_init(mdesc);
832 top_pmd = pmd_off_k(0xffff0000);
835 * allocate the zero page. Note that we count on this going ok.
837 zero_page = alloc_bootmem_low_pages(PAGE_SIZE);
838 memzero(zero_page, PAGE_SIZE);
839 empty_zero_page = virt_to_page(zero_page);
840 flush_dcache_page(empty_zero_page);
844 * In order to soft-boot, we need to insert a 1:1 mapping in place of
845 * the user-mode pages. This will then ensure that we have predictable
846 * results when turning the mmu off
848 void setup_mm_for_reboot(char mode)
850 unsigned long base_pmdval;
854 if (current->mm && current->mm->pgd)
855 pgd = current->mm->pgd;
859 base_pmdval = PMD_SECT_AP_WRITE | PMD_SECT_AP_READ | PMD_TYPE_SECT;
860 if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale())
861 base_pmdval |= PMD_BIT4;
863 for (i = 0; i < FIRST_USER_PGD_NR + USER_PTRS_PER_PGD; i++, pgd++) {
864 unsigned long pmdval = (i << PGDIR_SHIFT) | base_pmdval;
867 pmd = pmd_off(pgd, i << PGDIR_SHIFT);
868 pmd[0] = __pmd(pmdval);
869 pmd[1] = __pmd(pmdval + (1 << (PGDIR_SHIFT - 1)));
870 flush_pmd_entry(pmd);