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-rw-r--r--arch/arm/mm/mmu-cma.c1080
1 files changed, 1080 insertions, 0 deletions
diff --git a/arch/arm/mm/mmu-cma.c b/arch/arm/mm/mmu-cma.c
new file mode 100644
index 0000000..d5a0a0b
--- /dev/null
+++ b/arch/arm/mm/mmu-cma.c
@@ -0,0 +1,1080 @@
+/*
+ * linux/arch/arm/mm/mmu.c
+ *
+ * Copyright (C) 1995-2005 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/mman.h>
+#include <linux/nodemask.h>
+#include <linux/memblock.h>
+#include <linux/fs.h>
+
+#include <asm/cputype.h>
+#include <asm/sections.h>
+#include <asm/cachetype.h>
+#include <asm/setup.h>
+#include <asm/sizes.h>
+#include <asm/smp_plat.h>
+#include <asm/tlb.h>
+#include <asm/highmem.h>
+#include <asm/traps.h>
+
+#include <asm/mach/arch.h>
+#include <asm/mach/map.h>
+
+#include "mm.h"
+
+/*
+ * empty_zero_page is a special page that is used for
+ * zero-initialized data and COW.
+ */
+struct page *empty_zero_page;
+EXPORT_SYMBOL(empty_zero_page);
+
+/*
+ * The pmd table for the upper-most set of pages.
+ */
+pmd_t *top_pmd;
+
+#define CPOLICY_UNCACHED 0
+#define CPOLICY_BUFFERED 1
+#define CPOLICY_WRITETHROUGH 2
+#define CPOLICY_WRITEBACK 3
+#define CPOLICY_WRITEALLOC 4
+
+static unsigned int cachepolicy __initdata = CPOLICY_WRITEBACK;
+static unsigned int ecc_mask = 0;
+pgprot_t pgprot_user;
+EXPORT_SYMBOL(pgprot_user);
+pgprot_t pgprot_kernel;
+EXPORT_SYMBOL(pgprot_kernel);
+
+struct cachepolicy {
+ const char policy[16];
+ unsigned int cr_mask;
+ unsigned int pmd;
+ pteval_t pte;
+};
+
+static struct cachepolicy cache_policies[] __initdata = {
+ {
+ .policy = "uncached",
+ .cr_mask = CR_W|CR_C,
+ .pmd = PMD_SECT_UNCACHED,
+ .pte = L_PTE_MT_UNCACHED,
+ }, {
+ .policy = "buffered",
+ .cr_mask = CR_C,
+ .pmd = PMD_SECT_BUFFERED,
+ .pte = L_PTE_MT_BUFFERABLE,
+ }, {
+ .policy = "writethrough",
+ .cr_mask = 0,
+ .pmd = PMD_SECT_WT,
+ .pte = L_PTE_MT_WRITETHROUGH,
+ }, {
+ .policy = "writeback",
+ .cr_mask = 0,
+ .pmd = PMD_SECT_WB,
+ .pte = L_PTE_MT_WRITEBACK,
+ }, {
+ .policy = "writealloc",
+ .cr_mask = 0,
+ .pmd = PMD_SECT_WBWA,
+ .pte = L_PTE_MT_WRITEALLOC,
+ }
+};
+
+/*
+ * These are useful for identifying cache coherency
+ * problems by allowing the cache or the cache and
+ * writebuffer to be turned off. (Note: the write
+ * buffer should not be on and the cache off).
+ */
+static int __init early_cachepolicy(char *p)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(cache_policies); i++) {
+ int len = strlen(cache_policies[i].policy);
+
+ if (memcmp(p, cache_policies[i].policy, len) == 0) {
+ cachepolicy = i;
+ cr_alignment &= ~cache_policies[i].cr_mask;
+ cr_no_alignment &= ~cache_policies[i].cr_mask;
+ break;
+ }
+ }
+ if (i == ARRAY_SIZE(cache_policies))
+ printk(KERN_ERR "ERROR: unknown or unsupported cache policy\n");
+ /*
+ * This restriction is partly to do with the way we boot; it is
+ * unpredictable to have memory mapped using two different sets of
+ * memory attributes (shared, type, and cache attribs). We can not
+ * change these attributes once the initial assembly has setup the
+ * page tables.
+ */
+ if (cpu_architecture() >= CPU_ARCH_ARMv6) {
+ printk(KERN_WARNING "Only cachepolicy=writeback supported on ARMv6 and later\n");
+ cachepolicy = CPOLICY_WRITEBACK;
+ }
+ flush_cache_all();
+ set_cr(cr_alignment);
+ return 0;
+}
+early_param("cachepolicy", early_cachepolicy);
+
+static int __init early_nocache(char *__unused)
+{
+ char *p = "buffered";
+ printk(KERN_WARNING "nocache is deprecated; use cachepolicy=%s\n", p);
+ early_cachepolicy(p);
+ return 0;
+}
+early_param("nocache", early_nocache);
+
+static int __init early_nowrite(char *__unused)
+{
+ char *p = "uncached";
+ printk(KERN_WARNING "nowb is deprecated; use cachepolicy=%s\n", p);
+ early_cachepolicy(p);
+ return 0;
+}
+early_param("nowb", early_nowrite);
+
+static int __init early_ecc(char *p)
+{
+ if (memcmp(p, "on", 2) == 0)
+ ecc_mask = PMD_PROTECTION;
+ else if (memcmp(p, "off", 3) == 0)
+ ecc_mask = 0;
+ return 0;
+}
+early_param("ecc", early_ecc);
+
+static int __init noalign_setup(char *__unused)
+{
+ cr_alignment &= ~CR_A;
+ cr_no_alignment &= ~CR_A;
+ set_cr(cr_alignment);
+ return 1;
+}
+__setup("noalign", noalign_setup);
+
+#ifndef CONFIG_SMP
+void adjust_cr(unsigned long mask, unsigned long set)
+{
+ unsigned long flags;
+
+ mask &= ~CR_A;
+
+ set &= mask;
+
+ local_irq_save(flags);
+
+ cr_no_alignment = (cr_no_alignment & ~mask) | set;
+ cr_alignment = (cr_alignment & ~mask) | set;
+
+ set_cr((get_cr() & ~mask) | set);
+
+ local_irq_restore(flags);
+}
+#endif
+
+#define PROT_PTE_DEVICE (L_PTE_PRESENT|L_PTE_YOUNG|L_PTE_DIRTY|L_PTE_XN)
+#define PROT_SECT_DEVICE (PMD_TYPE_SECT|PMD_SECT_AP_WRITE)
+
+static struct mem_type mem_types[] = {
+ [MT_DEVICE] = { /* Strongly ordered / ARMv6 shared device */
+ .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_SHARED |
+ L_PTE_SHARED,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .prot_sect = PROT_SECT_DEVICE | PMD_SECT_S,
+ .domain = DOMAIN_IO,
+ },
+ [MT_DEVICE_NONSHARED] = { /* ARMv6 non-shared device */
+ .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_NONSHARED,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .prot_sect = PROT_SECT_DEVICE,
+ .domain = DOMAIN_IO,
+ },
+ [MT_DEVICE_CACHED] = { /* ioremap_cached */
+ .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_CACHED,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .prot_sect = PROT_SECT_DEVICE | PMD_SECT_WB,
+ .domain = DOMAIN_IO,
+ },
+ [MT_DEVICE_WC] = { /* ioremap_wc */
+ .prot_pte = PROT_PTE_DEVICE | L_PTE_MT_DEV_WC,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .prot_sect = PROT_SECT_DEVICE,
+ .domain = DOMAIN_IO,
+ },
+ [MT_UNCACHED] = {
+ .prot_pte = PROT_PTE_DEVICE,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
+ .domain = DOMAIN_IO,
+ },
+ [MT_CACHECLEAN] = {
+ .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
+ .domain = DOMAIN_KERNEL,
+ },
+ [MT_MINICLEAN] = {
+ .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN | PMD_SECT_MINICACHE,
+ .domain = DOMAIN_KERNEL,
+ },
+ [MT_LOW_VECTORS] = {
+ .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
+ L_PTE_RDONLY,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .domain = DOMAIN_USER,
+ },
+ [MT_HIGH_VECTORS] = {
+ .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
+ L_PTE_USER | L_PTE_RDONLY,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .domain = DOMAIN_USER,
+ },
+ [MT_MEMORY] = {
+ .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
+ .domain = DOMAIN_KERNEL,
+ },
+ [MT_ROM] = {
+ .prot_sect = PMD_TYPE_SECT,
+ .domain = DOMAIN_KERNEL,
+ },
+ [MT_MEMORY_NONCACHED] = {
+ .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
+ L_PTE_MT_BUFFERABLE,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
+ .domain = DOMAIN_KERNEL,
+ },
+ [MT_MEMORY_DTCM] = {
+ .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
+ L_PTE_XN,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN,
+ .domain = DOMAIN_KERNEL,
+ },
+ [MT_MEMORY_ITCM] = {
+ .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .domain = DOMAIN_KERNEL,
+ },
+ [MT_MEMORY_SO] = {
+ .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
+ L_PTE_MT_UNCACHED,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_SECT_S |
+ PMD_SECT_UNCACHED | PMD_SECT_XN,
+ .domain = DOMAIN_KERNEL,
+ },
+ [MT_MEMORY_DMA_READY] = {
+ .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .domain = DOMAIN_KERNEL,
+ },
+};
+
+const struct mem_type *get_mem_type(unsigned int type)
+{
+ return type < ARRAY_SIZE(mem_types) ? &mem_types[type] : NULL;
+}
+EXPORT_SYMBOL(get_mem_type);
+
+/*
+ * Adjust the PMD section entries according to the CPU in use.
+ */
+static void __init build_mem_type_table(void)
+{
+ struct cachepolicy *cp;
+ unsigned int cr = get_cr();
+ unsigned int user_pgprot, kern_pgprot, vecs_pgprot;
+ int cpu_arch = cpu_architecture();
+ int i;
+
+ if (cpu_arch < CPU_ARCH_ARMv6) {
+#if defined(CONFIG_CPU_DCACHE_DISABLE)
+ if (cachepolicy > CPOLICY_BUFFERED)
+ cachepolicy = CPOLICY_BUFFERED;
+#elif defined(CONFIG_CPU_DCACHE_WRITETHROUGH)
+ if (cachepolicy > CPOLICY_WRITETHROUGH)
+ cachepolicy = CPOLICY_WRITETHROUGH;
+#endif
+ }
+ if (cpu_arch < CPU_ARCH_ARMv5) {
+ if (cachepolicy >= CPOLICY_WRITEALLOC)
+ cachepolicy = CPOLICY_WRITEBACK;
+ ecc_mask = 0;
+ }
+ if (is_smp())
+ cachepolicy = CPOLICY_WRITEALLOC;
+
+ /*
+ * Strip out features not present on earlier architectures.
+ * Pre-ARMv5 CPUs don't have TEX bits. Pre-ARMv6 CPUs or those
+ * without extended page tables don't have the 'Shared' bit.
+ */
+ if (cpu_arch < CPU_ARCH_ARMv5)
+ for (i = 0; i < ARRAY_SIZE(mem_types); i++)
+ mem_types[i].prot_sect &= ~PMD_SECT_TEX(7);
+ if ((cpu_arch < CPU_ARCH_ARMv6 || !(cr & CR_XP)) && !cpu_is_xsc3())
+ for (i = 0; i < ARRAY_SIZE(mem_types); i++)
+ mem_types[i].prot_sect &= ~PMD_SECT_S;
+
+ /*
+ * ARMv5 and lower, bit 4 must be set for page tables (was: cache
+ * "update-able on write" bit on ARM610). However, Xscale and
+ * Xscale3 require this bit to be cleared.
+ */
+ if (cpu_is_xscale() || cpu_is_xsc3()) {
+ for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
+ mem_types[i].prot_sect &= ~PMD_BIT4;
+ mem_types[i].prot_l1 &= ~PMD_BIT4;
+ }
+ } else if (cpu_arch < CPU_ARCH_ARMv6) {
+ for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
+ if (mem_types[i].prot_l1)
+ mem_types[i].prot_l1 |= PMD_BIT4;
+ if (mem_types[i].prot_sect)
+ mem_types[i].prot_sect |= PMD_BIT4;
+ }
+ }
+
+ /*
+ * Mark the device areas according to the CPU/architecture.
+ */
+ if (cpu_is_xsc3() || (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP))) {
+ if (!cpu_is_xsc3()) {
+ /*
+ * Mark device regions on ARMv6+ as execute-never
+ * to prevent speculative instruction fetches.
+ */
+ mem_types[MT_DEVICE].prot_sect |= PMD_SECT_XN;
+ mem_types[MT_DEVICE_NONSHARED].prot_sect |= PMD_SECT_XN;
+ mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_XN;
+ mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_XN;
+ }
+ if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
+ /*
+ * For ARMv7 with TEX remapping,
+ * - shared device is SXCB=1100
+ * - nonshared device is SXCB=0100
+ * - write combine device mem is SXCB=0001
+ * (Uncached Normal memory)
+ */
+ mem_types[MT_DEVICE].prot_sect |= PMD_SECT_TEX(1);
+ mem_types[MT_DEVICE_NONSHARED].prot_sect
+ |= PMD_SECT_TEX(1);
+ mem_types[MT_DEVICE_WC].prot_sect
+ |= PMD_SECT_BUFFERABLE;
+ } else if (cpu_is_xsc3()) {
+ /*
+ * For Xscale3,
+ * - shared device is TEXCB=00101
+ * - nonshared device is TEXCB=01000
+ * - write combine device mem is TEXCB=00100
+ * (Inner/Outer Uncacheable in xsc3 parlance)
+ */
+ mem_types[MT_DEVICE].prot_sect |= PMD_SECT_TEX(1)
+ | PMD_SECT_BUFFERED;
+ mem_types[MT_DEVICE_NONSHARED].prot_sect
+ |= PMD_SECT_TEX(2);
+ mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1);
+ } else {
+ /*
+ * For ARMv6 and ARMv7 without TEX remapping,
+ * - shared device is TEXCB=00001
+ * - nonshared device is TEXCB=01000
+ * - write combine device mem is TEXCB=00100
+ * (Uncached Normal in ARMv6 parlance).
+ */
+ mem_types[MT_DEVICE].prot_sect |= PMD_SECT_BUFFERED;
+ mem_types[MT_DEVICE_NONSHARED].prot_sect
+ |= PMD_SECT_TEX(2);
+ mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_TEX(1);
+ }
+ } else {
+ /*
+ * On others, write combining is "Uncached/Buffered"
+ */
+ mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_BUFFERABLE;
+ }
+
+ /*
+ * Now deal with the memory-type mappings
+ */
+ cp = &cache_policies[cachepolicy];
+ vecs_pgprot = kern_pgprot = user_pgprot = cp->pte;
+
+ /*
+ * Only use write-through for non-SMP systems
+ */
+ if (!is_smp() && cpu_arch >= CPU_ARCH_ARMv5
+ && cachepolicy > CPOLICY_WRITETHROUGH)
+ vecs_pgprot = cache_policies[CPOLICY_WRITETHROUGH].pte;
+
+ /*
+ * Enable CPU-specific coherency if supported.
+ * (Only available on XSC3 at the moment.)
+ */
+ if (arch_is_coherent() && cpu_is_xsc3()) {
+ mem_types[MT_MEMORY].prot_sect |= PMD_SECT_S;
+ mem_types[MT_MEMORY].prot_pte |= L_PTE_SHARED;
+ mem_types[MT_MEMORY_DMA_READY].prot_pte |= L_PTE_SHARED;
+ mem_types[MT_MEMORY_NONCACHED].prot_sect |= PMD_SECT_S;
+ mem_types[MT_MEMORY_NONCACHED].prot_pte |= L_PTE_SHARED;
+ }
+ /*
+ * ARMv6 and above have extended page tables.
+ */
+ if (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP)) {
+ /*
+ * Mark cache clean areas and XIP ROM read only
+ * from SVC mode and no access from userspace.
+ */
+ mem_types[MT_ROM].prot_sect |= PMD_SECT_APX
+ | PMD_SECT_AP_WRITE;
+ mem_types[MT_MINICLEAN].prot_sect |= PMD_SECT_APX
+ | PMD_SECT_AP_WRITE;
+ mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_APX
+ | PMD_SECT_AP_WRITE;
+
+ if (is_smp()) {
+ /*
+ * Mark memory with the "shared" attribute
+ * for SMP systems
+ */
+ user_pgprot |= L_PTE_SHARED;
+ kern_pgprot |= L_PTE_SHARED;
+ vecs_pgprot |= L_PTE_SHARED;
+ mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_S;
+ mem_types[MT_DEVICE_WC].prot_pte |= L_PTE_SHARED;
+ mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_S;
+ mem_types[MT_DEVICE_CACHED].prot_pte |= L_PTE_SHARED;
+ mem_types[MT_MEMORY].prot_sect |= PMD_SECT_S;
+ mem_types[MT_MEMORY].prot_pte |= L_PTE_SHARED;
+ mem_types[MT_MEMORY_DMA_READY].prot_pte |= L_PTE_SHARED;
+ mem_types[MT_MEMORY_NONCACHED].prot_sect |= PMD_SECT_S;
+ mem_types[MT_MEMORY_NONCACHED].prot_pte |= L_PTE_SHARED;
+ }
+ }
+
+ /*
+ * Non-cacheable Normal - intended for memory areas that must
+ * not cause dirty cache line writebacks when used
+ */
+ if (cpu_arch >= CPU_ARCH_ARMv6) {
+ if (cpu_arch >= CPU_ARCH_ARMv7 && (cr & CR_TRE)) {
+ /* Non-cacheable Normal is XCB = 001 */
+ mem_types[MT_MEMORY_NONCACHED].prot_sect |=
+ PMD_SECT_BUFFERED;
+ } else {
+ /* For both ARMv6 and non-TEX-remapping ARMv7 */
+ mem_types[MT_MEMORY_NONCACHED].prot_sect |=
+ PMD_SECT_TEX(1);
+ }
+ } else {
+ mem_types[MT_MEMORY_NONCACHED].prot_sect |= PMD_SECT_BUFFERABLE;
+ }
+
+ for (i = 0; i < 16; i++) {
+ unsigned long v = pgprot_val(protection_map[i]);
+ protection_map[i] = __pgprot(v | user_pgprot);
+ }
+
+ mem_types[MT_LOW_VECTORS].prot_pte |= vecs_pgprot;
+ mem_types[MT_HIGH_VECTORS].prot_pte |= vecs_pgprot;
+
+ pgprot_user = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | user_pgprot);
+ pgprot_kernel = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG |
+ L_PTE_DIRTY | kern_pgprot);
+
+ mem_types[MT_LOW_VECTORS].prot_l1 |= ecc_mask;
+ mem_types[MT_HIGH_VECTORS].prot_l1 |= ecc_mask;
+ mem_types[MT_MEMORY].prot_sect |= ecc_mask | cp->pmd;
+ mem_types[MT_MEMORY].prot_pte |= kern_pgprot;
+ mem_types[MT_MEMORY_DMA_READY].prot_pte |= kern_pgprot;
+ mem_types[MT_MEMORY_NONCACHED].prot_sect |= ecc_mask;
+ mem_types[MT_ROM].prot_sect |= cp->pmd;
+
+ switch (cp->pmd) {
+ case PMD_SECT_WT:
+ mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WT;
+ break;
+ case PMD_SECT_WB:
+ case PMD_SECT_WBWA:
+ mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WB;
+ break;
+ }
+ printk(KERN_INFO "Memory policy: ECC %sabled, Data cache %s\n",
+ ecc_mask ? "en" : "dis", cp->policy);
+
+ for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
+ struct mem_type *t = &mem_types[i];
+ if (t->prot_l1)
+ t->prot_l1 |= PMD_DOMAIN(t->domain);
+ if (t->prot_sect)
+ t->prot_sect |= PMD_DOMAIN(t->domain);
+ }
+}
+
+#ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
+pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
+ unsigned long size, pgprot_t vma_prot)
+{
+ if (!pfn_valid(pfn))
+ return pgprot_noncached(vma_prot);
+ else if (file->f_flags & O_SYNC)
+ return pgprot_writecombine(vma_prot);
+ return vma_prot;
+}
+EXPORT_SYMBOL(phys_mem_access_prot);
+#endif
+
+#define vectors_base() (vectors_high() ? 0xffff0000 : 0)
+
+static void __init *early_alloc(unsigned long sz)
+{
+ void *ptr = __va(memblock_alloc(sz, sz));
+ memset(ptr, 0, sz);
+ return ptr;
+}
+
+static pte_t * __init early_pte_alloc(pmd_t *pmd, unsigned long addr,
+ unsigned long prot)
+{
+ if (pmd_none(*pmd)) {
+ pte_t *pte = early_alloc(PTE_HWTABLE_OFF + PTE_HWTABLE_SIZE);
+ __pmd_populate(pmd, __pa(pte), prot);
+ }
+ BUG_ON(pmd_bad(*pmd));
+ return pte_offset_kernel(pmd, addr);
+}
+
+static void __init alloc_init_pte(pmd_t *pmd, unsigned long addr,
+ unsigned long end, unsigned long pfn,
+ const struct mem_type *type)
+{
+ pte_t *pte = early_pte_alloc(pmd, addr, type->prot_l1);
+ do {
+ set_pte_ext(pte, pfn_pte(pfn, __pgprot(type->prot_pte)), 0);
+ pfn++;
+ } while (pte++, addr += PAGE_SIZE, addr != end);
+}
+
+static void __init alloc_init_section(pud_t *pud, unsigned long addr,
+ unsigned long end, phys_addr_t phys,
+ const struct mem_type *type)
+{
+ pmd_t *pmd = pmd_offset(pud, addr);
+
+ /*
+ * Try a section mapping - end, addr and phys must all be aligned
+ * to a section boundary. Note that PMDs refer to the individual
+ * L1 entries, whereas PGDs refer to a group of L1 entries making
+ * up one logical pointer to an L2 table.
+ */
+ if (type->prot_sect && ((addr | end | phys) & ~SECTION_MASK) == 0) {
+ pmd_t *p = pmd;
+
+ if (addr & SECTION_SIZE)
+ pmd++;
+
+ do {
+ *pmd = __pmd(phys | type->prot_sect);
+ phys += SECTION_SIZE;
+ } while (pmd++, addr += SECTION_SIZE, addr != end);
+
+ flush_pmd_entry(p);
+ } else {
+ /*
+ * No need to loop; pte's aren't interested in the
+ * individual L1 entries.
+ */
+ alloc_init_pte(pmd, addr, end, __phys_to_pfn(phys), type);
+ }
+}
+
+static void alloc_init_pud(pgd_t *pgd, unsigned long addr, unsigned long end,
+ unsigned long phys, const struct mem_type *type)
+{
+ pud_t *pud = pud_offset(pgd, addr);
+ unsigned long next;
+
+ do {
+ next = pud_addr_end(addr, end);
+ alloc_init_section(pud, addr, next, phys, type);
+ phys += next - addr;
+ } while (pud++, addr = next, addr != end);
+}
+
+static void __init create_36bit_mapping(struct map_desc *md,
+ const struct mem_type *type)
+{
+ unsigned long addr, length, end;
+ phys_addr_t phys;
+ pgd_t *pgd;
+
+ addr = md->virtual;
+ phys = __pfn_to_phys(md->pfn);
+ length = PAGE_ALIGN(md->length);
+
+ if (!(cpu_architecture() >= CPU_ARCH_ARMv6 || cpu_is_xsc3())) {
+ printk(KERN_ERR "MM: CPU does not support supersection "
+ "mapping for 0x%08llx at 0x%08lx\n",
+ (long long)__pfn_to_phys((u64)md->pfn), addr);
+ return;
+ }
+
+ /* N.B. ARMv6 supersections are only defined to work with domain 0.
+ * Since domain assignments can in fact be arbitrary, the
+ * 'domain == 0' check below is required to insure that ARMv6
+ * supersections are only allocated for domain 0 regardless
+ * of the actual domain assignments in use.
+ */
+ if (type->domain) {
+ printk(KERN_ERR "MM: invalid domain in supersection "
+ "mapping for 0x%08llx at 0x%08lx\n",
+ (long long)__pfn_to_phys((u64)md->pfn), addr);
+ return;
+ }
+
+ if ((addr | length | __pfn_to_phys(md->pfn)) & ~SUPERSECTION_MASK) {
+ printk(KERN_ERR "MM: cannot create mapping for 0x%08llx"
+ " at 0x%08lx invalid alignment\n",
+ (long long)__pfn_to_phys((u64)md->pfn), addr);
+ return;
+ }
+
+ /*
+ * Shift bits [35:32] of address into bits [23:20] of PMD
+ * (See ARMv6 spec).
+ */
+ phys |= (((md->pfn >> (32 - PAGE_SHIFT)) & 0xF) << 20);
+
+ pgd = pgd_offset_k(addr);
+ end = addr + length;
+ do {
+ pud_t *pud = pud_offset(pgd, addr);
+ pmd_t *pmd = pmd_offset(pud, addr);
+ int i;
+
+ for (i = 0; i < 16; i++)
+ *pmd++ = __pmd(phys | type->prot_sect | PMD_SECT_SUPER);
+
+ addr += SUPERSECTION_SIZE;
+ phys += SUPERSECTION_SIZE;
+ pgd += SUPERSECTION_SIZE >> PGDIR_SHIFT;
+ } while (addr != end);
+}
+
+/*
+ * Create the page directory entries and any necessary
+ * page tables for the mapping specified by `md'. We
+ * are able to cope here with varying sizes and address
+ * offsets, and we take full advantage of sections and
+ * supersections.
+ */
+static void __init create_mapping(struct map_desc *md)
+{
+ unsigned long addr, length, end;
+ phys_addr_t phys;
+ const struct mem_type *type;
+ pgd_t *pgd;
+
+ if (md->virtual != vectors_base() && md->virtual < TASK_SIZE) {
+ printk(KERN_WARNING "BUG: not creating mapping for 0x%08llx"
+ " at 0x%08lx in user region\n",
+ (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
+ return;
+ }
+
+ if ((md->type == MT_DEVICE || md->type == MT_ROM) &&
+ md->virtual >= PAGE_OFFSET && md->virtual < VMALLOC_END) {
+ printk(KERN_WARNING "BUG: mapping for 0x%08llx"
+ " at 0x%08lx overlaps vmalloc space\n",
+ (long long)__pfn_to_phys((u64)md->pfn), md->virtual);
+ }
+
+ type = &mem_types[md->type];
+
+ /*
+ * Catch 36-bit addresses
+ */
+ if (md->pfn >= 0x100000) {
+ create_36bit_mapping(md, type);
+ return;
+ }
+
+ addr = md->virtual & PAGE_MASK;
+ phys = __pfn_to_phys(md->pfn);
+ length = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK));
+
+ if (type->prot_l1 == 0 && ((addr | phys | length) & ~SECTION_MASK)) {
+ printk(KERN_WARNING "BUG: map for 0x%08llx at 0x%08lx can not "
+ "be mapped using pages, ignoring.\n",
+ (long long)__pfn_to_phys(md->pfn), addr);
+ return;
+ }
+
+ pgd = pgd_offset_k(addr);
+ end = addr + length;
+ do {
+ unsigned long next = pgd_addr_end(addr, end);
+
+ alloc_init_pud(pgd, addr, next, phys, type);
+
+ phys += next - addr;
+ addr = next;
+ } while (pgd++, addr != end);
+}
+
+/*
+ * Create the architecture specific mappings
+ */
+void __init iotable_init(struct map_desc *io_desc, int nr)
+{
+ int i;
+
+ for (i = 0; i < nr; i++)
+ create_mapping(io_desc + i);
+}
+
+static void * __initdata vmalloc_min = (void *)(VMALLOC_END - SZ_128M);
+
+/*
+ * vmalloc=size forces the vmalloc area to be exactly 'size'
+ * bytes. This can be used to increase (or decrease) the vmalloc
+ * area - the default is 128m.
+ */
+static int __init early_vmalloc(char *arg)
+{
+ unsigned long vmalloc_reserve = memparse(arg, NULL);
+
+ if (vmalloc_reserve < SZ_16M) {
+ vmalloc_reserve = SZ_16M;
+ printk(KERN_WARNING
+ "vmalloc area too small, limiting to %luMB\n",
+ vmalloc_reserve >> 20);
+ }
+
+ if (vmalloc_reserve > VMALLOC_END - (PAGE_OFFSET + SZ_32M)) {
+ vmalloc_reserve = VMALLOC_END - (PAGE_OFFSET + SZ_32M);
+ printk(KERN_WARNING
+ "vmalloc area is too big, limiting to %luMB\n",
+ vmalloc_reserve >> 20);
+ }
+
+ vmalloc_min = (void *)(VMALLOC_END - vmalloc_reserve);
+ return 0;
+}
+early_param("vmalloc", early_vmalloc);
+
+phys_addr_t arm_lowmem_limit = 0;
+
+void __init sanity_check_meminfo(void)
+{
+ int i, j, highmem = 0;
+
+ for (i = 0, j = 0; i < meminfo.nr_banks; i++) {
+ struct membank *bank = &meminfo.bank[j];
+ *bank = meminfo.bank[i];
+
+#ifdef CONFIG_HIGHMEM
+ if (__va(bank->start) >= vmalloc_min ||
+ __va(bank->start) < (void *)PAGE_OFFSET)
+ highmem = 1;
+
+ bank->highmem = highmem;
+
+ /*
+ * Split those memory banks which are partially overlapping
+ * the vmalloc area greatly simplifying things later.
+ */
+ if (__va(bank->start) < vmalloc_min &&
+ bank->size > vmalloc_min - __va(bank->start)) {
+ if (meminfo.nr_banks >= NR_BANKS) {
+ printk(KERN_CRIT "NR_BANKS too low, "
+ "ignoring high memory\n");
+ } else {
+ memmove(bank + 1, bank,
+ (meminfo.nr_banks - i) * sizeof(*bank));
+ meminfo.nr_banks++;
+ i++;
+ bank[1].size -= vmalloc_min - __va(bank->start);
+ bank[1].start = __pa(vmalloc_min - 1) + 1;
+ bank[1].highmem = highmem = 1;
+ j++;
+ }
+ bank->size = vmalloc_min - __va(bank->start);
+ }
+#else
+ bank->highmem = highmem;
+
+ /*
+ * Check whether this memory bank would entirely overlap
+ * the vmalloc area.
+ */
+ if (__va(bank->start) >= vmalloc_min ||
+ __va(bank->start) < (void *)PAGE_OFFSET) {
+ printk(KERN_NOTICE "Ignoring RAM at %.8llx-%.8llx "
+ "(vmalloc region overlap).\n",
+ (unsigned long long)bank->start,
+ (unsigned long long)bank->start + bank->size - 1);
+ continue;
+ }
+
+ /*
+ * Check whether this memory bank would partially overlap
+ * the vmalloc area.
+ */
+ if (__va(bank->start + bank->size) > vmalloc_min ||
+ __va(bank->start + bank->size) < __va(bank->start)) {
+ unsigned long newsize = vmalloc_min - __va(bank->start);
+ printk(KERN_NOTICE "Truncating RAM at %.8llx-%.8llx "
+ "to -%.8llx (vmalloc region overlap).\n",
+ (unsigned long long)bank->start,
+ (unsigned long long)bank->start + bank->size - 1,
+ (unsigned long long)bank->start + newsize - 1);
+ bank->size = newsize;
+ }
+#endif
+ if (!bank->highmem && bank->start + bank->size
+ > arm_lowmem_limit)
+ arm_lowmem_limit = bank->start + bank->size;
+
+ j++;
+ }
+#ifdef CONFIG_HIGHMEM
+ if (highmem) {
+ const char *reason = NULL;
+
+ if (cache_is_vipt_aliasing()) {
+ /*
+ * Interactions between kmap and other mappings
+ * make highmem support with aliasing VIPT caches
+ * rather difficult.
+ */
+ reason = "with VIPT aliasing cache";
+ }
+ if (reason) {
+ printk(KERN_CRIT "HIGHMEM is not supported %s,"
+ " ignoring high memory\n", reason);
+ while (j > 0 && meminfo.bank[j - 1].highmem)
+ j--;
+ }
+ }
+#endif
+ meminfo.nr_banks = j;
+ memblock_set_current_limit(arm_lowmem_limit);
+}
+
+static inline void prepare_page_table(void)
+{
+ unsigned long addr;
+ phys_addr_t end;
+
+ /*
+ * Clear out all the mappings below the kernel image.
+ */
+ for (addr = 0; addr < MODULES_VADDR; addr += PGDIR_SIZE)
+ pmd_clear(pmd_off_k(addr));
+
+#ifdef CONFIG_XIP_KERNEL
+ /* The XIP kernel is mapped in the module area -- skip over it */
+ addr = ((unsigned long)_etext + PGDIR_SIZE - 1) & PGDIR_MASK;
+#endif
+ for ( ; addr < PAGE_OFFSET; addr += PGDIR_SIZE)
+ pmd_clear(pmd_off_k(addr));
+
+ /*
+ * Find the end of the first block of lowmem.
+ */
+ end = memblock.memory.regions[0].base + memblock.memory.regions[0].size;
+ if (end >= arm_lowmem_limit)
+ end = arm_lowmem_limit;
+
+ /*
+ * Clear out all the kernel space mappings, except for the first
+ * memory bank, up to the end of the vmalloc region.
+ */
+ for (addr = __phys_to_virt(end);
+ addr < VMALLOC_END; addr += PGDIR_SIZE)
+ pmd_clear(pmd_off_k(addr));
+}
+
+/*
+ * Reserve the special regions of memory
+ */
+void __init arm_mm_memblock_reserve(void)
+{
+ /*
+ * Reserve the page tables. These are already in use,
+ * and can only be in node 0.
+ */
+ memblock_reserve(__pa(swapper_pg_dir), PTRS_PER_PGD * sizeof(pgd_t));
+
+#ifdef CONFIG_SA1111
+ /*
+ * Because of the SA1111 DMA bug, we want to preserve our
+ * precious DMA-able memory...
+ */
+ memblock_reserve(PHYS_OFFSET, __pa(swapper_pg_dir) - PHYS_OFFSET);
+#endif
+}
+
+/*
+ * Set up device the mappings. Since we clear out the page tables for all
+ * mappings above VMALLOC_END, we will remove any debug device mappings.
+ * This means you have to be careful how you debug this function, or any
+ * called function. This means you can't use any function or debugging
+ * method which may touch any device, otherwise the kernel _will_ crash.
+ */
+static void __init devicemaps_init(struct machine_desc *mdesc)
+{
+ struct map_desc map;
+ unsigned long addr;
+
+ /*
+ * Allocate the vector page early.
+ */
+ vectors_page = early_alloc(PAGE_SIZE);
+
+ for (addr = VMALLOC_END; addr; addr += PGDIR_SIZE)
+ pmd_clear(pmd_off_k(addr));
+
+ /*
+ * Map the kernel if it is XIP.
+ * It is always first in the modulearea.
+ */
+#ifdef CONFIG_XIP_KERNEL
+ map.pfn = __phys_to_pfn(CONFIG_XIP_PHYS_ADDR & SECTION_MASK);
+ map.virtual = MODULES_VADDR;
+ map.length = ((unsigned long)_etext - map.virtual + ~SECTION_MASK)
+ & SECTION_MASK;
+ map.type = MT_ROM;
+ create_mapping(&map);
+#endif
+
+ /*
+ * Map the cache flushing regions.
+ */
+#ifdef FLUSH_BASE
+ map.pfn = __phys_to_pfn(FLUSH_BASE_PHYS);
+ map.virtual = FLUSH_BASE;
+ map.length = SZ_1M;
+ map.type = MT_CACHECLEAN;
+ create_mapping(&map);
+#endif
+#ifdef FLUSH_BASE_MINICACHE
+ map.pfn = __phys_to_pfn(FLUSH_BASE_PHYS + SZ_1M);
+ map.virtual = FLUSH_BASE_MINICACHE;
+ map.length = SZ_1M;
+ map.type = MT_MINICLEAN;
+ create_mapping(&map);
+#endif
+
+ /*
+ * Create a mapping for the machine vectors at the high-vectors
+ * location (0xffff0000). If we aren't using high-vectors, also
+ * create a mapping at the low-vectors virtual address.
+ */
+ map.pfn = __phys_to_pfn(virt_to_phys(vectors_page));
+ map.virtual = 0xffff0000;
+ map.length = PAGE_SIZE;
+ map.type = MT_HIGH_VECTORS;
+ create_mapping(&map);
+
+ if (!vectors_high()) {
+ map.virtual = 0;
+ map.type = MT_LOW_VECTORS;
+ create_mapping(&map);
+ }
+
+ /*
+ * Ask the machine support to map in the statically mapped devices.
+ */
+ if (mdesc->map_io)
+ mdesc->map_io();
+
+ /*
+ * Finally flush the caches and tlb to ensure that we're in a
+ * consistent state wrt the writebuffer. This also ensures that
+ * any write-allocated cache lines in the vector page are written
+ * back. After this point, we can start to touch devices again.
+ */
+ local_flush_tlb_all();
+ flush_cache_all();
+}
+
+static void __init kmap_init(void)
+{
+#ifdef CONFIG_HIGHMEM
+ pkmap_page_table = early_pte_alloc(pmd_off_k(PKMAP_BASE),
+ PKMAP_BASE, _PAGE_KERNEL_TABLE);
+#endif
+}
+
+static void __init map_lowmem(void)
+{
+ struct memblock_region *reg;
+
+ /* Map all the lowmem memory banks. */
+ for_each_memblock(memory, reg) {
+ phys_addr_t start = reg->base;
+ phys_addr_t end = start + reg->size;
+ struct map_desc map;
+
+ if (end > arm_lowmem_limit)
+ end = arm_lowmem_limit;
+ if (start >= end)
+ break;
+
+ map.pfn = __phys_to_pfn(start);
+ map.virtual = __phys_to_virt(start);
+ map.length = end - start;
+ map.type = MT_MEMORY;
+
+ create_mapping(&map);
+ }
+}
+
+/*
+ * paging_init() sets up the page tables, initialises the zone memory
+ * maps, and sets up the zero page, bad page and bad page tables.
+ */
+void __init paging_init(struct machine_desc *mdesc)
+{
+ void *zero_page;
+
+ memblock_set_current_limit(arm_lowmem_limit);
+
+ build_mem_type_table();
+ prepare_page_table();
+ map_lowmem();
+ dma_contiguous_remap();
+ devicemaps_init(mdesc);
+ kmap_init();
+
+ top_pmd = pmd_off_k(0xffff0000);
+
+ /* allocate the zero page. */
+ zero_page = early_alloc(PAGE_SIZE);
+
+ bootmem_init();
+
+ empty_zero_page = virt_to_page(zero_page);
+ __flush_dcache_page(NULL, empty_zero_page);
+}