diff options
Diffstat (limited to 'arch/arm/mm/mmu.c')
| -rw-r--r-- | arch/arm/mm/mmu.c | 1536 |
1 files changed, 1536 insertions, 0 deletions
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c new file mode 100644 index 000000000..718638267 --- /dev/null +++ b/arch/arm/mm/mmu.c @@ -0,0 +1,1536 @@ +/* + * 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 <linux/vmalloc.h> +#include <linux/sizes.h> + +#include <asm/cp15.h> +#include <asm/cputype.h> +#include <asm/sections.h> +#include <asm/cachetype.h> +#include <asm/fixmap.h> +#include <asm/sections.h> +#include <asm/setup.h> +#include <asm/smp_plat.h> +#include <asm/tlb.h> +#include <asm/highmem.h> +#include <asm/system_info.h> +#include <asm/traps.h> +#include <asm/procinfo.h> +#include <asm/memory.h> + +#include <asm/mach/arch.h> +#include <asm/mach/map.h> +#include <asm/mach/pci.h> +#include <asm/fixmap.h> + +#include "mm.h" +#include "tcm.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; + +pmdval_t user_pmd_table = _PAGE_USER_TABLE; + +#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 __initdata = 0; +pgprot_t pgprot_user; +pgprot_t pgprot_kernel; +pgprot_t pgprot_hyp_device; +pgprot_t pgprot_s2; +pgprot_t pgprot_s2_device; + +EXPORT_SYMBOL(pgprot_user); +EXPORT_SYMBOL(pgprot_kernel); + +struct cachepolicy { + const char policy[16]; + unsigned int cr_mask; + pmdval_t pmd; + pteval_t pte; + pteval_t pte_s2; +}; + +#ifdef CONFIG_ARM_LPAE +#define s2_policy(policy) policy +#else +#define s2_policy(policy) 0 +#endif + +static struct cachepolicy cache_policies[] __initdata = { + { + .policy = "uncached", + .cr_mask = CR_W|CR_C, + .pmd = PMD_SECT_UNCACHED, + .pte = L_PTE_MT_UNCACHED, + .pte_s2 = s2_policy(L_PTE_S2_MT_UNCACHED), + }, { + .policy = "buffered", + .cr_mask = CR_C, + .pmd = PMD_SECT_BUFFERED, + .pte = L_PTE_MT_BUFFERABLE, + .pte_s2 = s2_policy(L_PTE_S2_MT_UNCACHED), + }, { + .policy = "writethrough", + .cr_mask = 0, + .pmd = PMD_SECT_WT, + .pte = L_PTE_MT_WRITETHROUGH, + .pte_s2 = s2_policy(L_PTE_S2_MT_WRITETHROUGH), + }, { + .policy = "writeback", + .cr_mask = 0, + .pmd = PMD_SECT_WB, + .pte = L_PTE_MT_WRITEBACK, + .pte_s2 = s2_policy(L_PTE_S2_MT_WRITEBACK), + }, { + .policy = "writealloc", + .cr_mask = 0, + .pmd = PMD_SECT_WBWA, + .pte = L_PTE_MT_WRITEALLOC, + .pte_s2 = s2_policy(L_PTE_S2_MT_WRITEBACK), + } +}; + +#ifdef CONFIG_CPU_CP15 +static unsigned long initial_pmd_value __initdata = 0; + +/* + * Initialise the cache_policy variable with the initial state specified + * via the "pmd" value. This is used to ensure that on ARMv6 and later, + * the C code sets the page tables up with the same policy as the head + * assembly code, which avoids an illegal state where the TLBs can get + * confused. See comments in early_cachepolicy() for more information. + */ +void __init init_default_cache_policy(unsigned long pmd) +{ + int i; + + initial_pmd_value = pmd; + + pmd &= PMD_SECT_TEX(1) | PMD_SECT_BUFFERABLE | PMD_SECT_CACHEABLE; + + for (i = 0; i < ARRAY_SIZE(cache_policies); i++) + if (cache_policies[i].pmd == pmd) { + cachepolicy = i; + break; + } + + if (i == ARRAY_SIZE(cache_policies)) + pr_err("ERROR: could not find cache policy\n"); +} + +/* + * 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, selected = -1; + + 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) { + selected = i; + break; + } + } + + if (selected == -1) + pr_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 && selected != cachepolicy) { + pr_warn("Only cachepolicy=%s supported on ARMv6 and later\n", + cache_policies[cachepolicy].policy); + return 0; + } + + if (selected != cachepolicy) { + unsigned long cr = __clear_cr(cache_policies[selected].cr_mask); + cachepolicy = selected; + flush_cache_all(); + set_cr(cr); + } + return 0; +} +early_param("cachepolicy", early_cachepolicy); + +static int __init early_nocache(char *__unused) +{ + char *p = "buffered"; + pr_warn("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"; + pr_warn("nowb is deprecated; use cachepolicy=%s\n", p); + early_cachepolicy(p); + return 0; +} +early_param("nowb", early_nowrite); + +#ifndef CONFIG_ARM_LPAE +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); +#endif + +#else /* ifdef CONFIG_CPU_CP15 */ + +static int __init early_cachepolicy(char *p) +{ + pr_warn("cachepolicy kernel parameter not supported without cp15\n"); +} +early_param("cachepolicy", early_cachepolicy); + +static int __init noalign_setup(char *__unused) +{ + pr_warn("noalign kernel parameter not supported without cp15\n"); +} +__setup("noalign", noalign_setup); + +#endif /* ifdef CONFIG_CPU_CP15 / else */ + +#define PROT_PTE_DEVICE L_PTE_PRESENT|L_PTE_YOUNG|L_PTE_DIRTY|L_PTE_XN +#define PROT_PTE_S2_DEVICE PROT_PTE_DEVICE +#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_pte_s2 = s2_policy(PROT_PTE_S2_DEVICE) | + s2_policy(L_PTE_S2_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, + }, +#ifndef CONFIG_ARM_LPAE + [MT_MINICLEAN] = { + .prot_sect = PMD_TYPE_SECT | PMD_SECT_XN | PMD_SECT_MINICACHE, + .domain = DOMAIN_KERNEL, + }, +#endif + [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_RWX] = { + .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_MEMORY_RW] = { + .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_AP_WRITE, + .domain = DOMAIN_KERNEL, + }, + [MT_ROM] = { + .prot_sect = PMD_TYPE_SECT, + .domain = DOMAIN_KERNEL, + }, + [MT_MEMORY_RWX_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_RW_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_RWX_ITCM] = { + .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY, + .prot_l1 = PMD_TYPE_TABLE, + .domain = DOMAIN_KERNEL, + }, + [MT_MEMORY_RW_SO] = { + .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY | + L_PTE_MT_UNCACHED | L_PTE_XN, + .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 | + L_PTE_XN, + .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); + +/* + * To avoid TLB flush broadcasts, this uses local_flush_tlb_kernel_range(). + * As a result, this can only be called with preemption disabled, as under + * stop_machine(). + */ +void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot) +{ + unsigned long vaddr = __fix_to_virt(idx); + pte_t *pte = pte_offset_kernel(pmd_off_k(vaddr), vaddr); + + /* Make sure fixmap region does not exceed available allocation. */ + BUILD_BUG_ON(FIXADDR_START + (__end_of_fixed_addresses * PAGE_SIZE) > + FIXADDR_END); + BUG_ON(idx >= __end_of_fixed_addresses); + + if (pgprot_val(prot)) + set_pte_at(NULL, vaddr, pte, + pfn_pte(phys >> PAGE_SHIFT, prot)); + else + pte_clear(NULL, vaddr, pte); + local_flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE); +} + +/* + * 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(); + pteval_t user_pgprot, kern_pgprot, vecs_pgprot; + pteval_t hyp_device_pgprot, s2_pgprot, s2_device_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()) { + if (cachepolicy != CPOLICY_WRITEALLOC) { + pr_warn("Forcing write-allocate cache policy for SMP\n"); + cachepolicy = CPOLICY_WRITEALLOC; + } + if (!(initial_pmd_value & PMD_SECT_S)) { + pr_warn("Forcing shared mappings for SMP\n"); + initial_pmd_value |= PMD_SECT_S; + } + } + + /* + * 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; + + /* Also setup NX memory mapping */ + mem_types[MT_MEMORY_RW].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; + s2_pgprot = cp->pte_s2; + hyp_device_pgprot = mem_types[MT_DEVICE].prot_pte; + s2_device_pgprot = mem_types[MT_DEVICE].prot_pte_s2; + +#ifndef CONFIG_ARM_LPAE + /* + * We don't use domains on ARMv6 (since this causes problems with + * v6/v7 kernels), so we must use a separate memory type for user + * r/o, kernel r/w to map the vectors page. + */ + if (cpu_arch == CPU_ARCH_ARMv6) + vecs_pgprot |= L_PTE_MT_VECTORS; + + /* + * Check is it with support for the PXN bit + * in the Short-descriptor translation table format descriptors. + */ + if (cpu_arch == CPU_ARCH_ARMv7 && + (read_cpuid_ext(CPUID_EXT_MMFR0) & 0xF) == 4) { + user_pmd_table |= PMD_PXNTABLE; + } +#endif + + /* + * ARMv6 and above have extended page tables. + */ + if (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP)) { +#ifndef CONFIG_ARM_LPAE + /* + * 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; +#endif + + /* + * If the initial page tables were created with the S bit + * set, then we need to do the same here for the same + * reasons given in early_cachepolicy(). + */ + if (initial_pmd_value & PMD_SECT_S) { + user_pgprot |= L_PTE_SHARED; + kern_pgprot |= L_PTE_SHARED; + vecs_pgprot |= L_PTE_SHARED; + s2_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_RWX].prot_sect |= PMD_SECT_S; + mem_types[MT_MEMORY_RWX].prot_pte |= L_PTE_SHARED; + mem_types[MT_MEMORY_RW].prot_sect |= PMD_SECT_S; + mem_types[MT_MEMORY_RW].prot_pte |= L_PTE_SHARED; + mem_types[MT_MEMORY_DMA_READY].prot_pte |= L_PTE_SHARED; + mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |= PMD_SECT_S; + mem_types[MT_MEMORY_RWX_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_RWX_NONCACHED].prot_sect |= + PMD_SECT_BUFFERED; + } else { + /* For both ARMv6 and non-TEX-remapping ARMv7 */ + mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |= + PMD_SECT_TEX(1); + } + } else { + mem_types[MT_MEMORY_RWX_NONCACHED].prot_sect |= PMD_SECT_BUFFERABLE; + } + +#ifdef CONFIG_ARM_LPAE + /* + * Do not generate access flag faults for the kernel mappings. + */ + for (i = 0; i < ARRAY_SIZE(mem_types); i++) { + mem_types[i].prot_pte |= PTE_EXT_AF; + if (mem_types[i].prot_sect) + mem_types[i].prot_sect |= PMD_SECT_AF; + } + kern_pgprot |= PTE_EXT_AF; + vecs_pgprot |= PTE_EXT_AF; + + /* + * Set PXN for user mappings + */ + user_pgprot |= PTE_EXT_PXN; +#endif + + for (i = 0; i < 16; i++) { + pteval_t 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); + pgprot_s2 = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | s2_pgprot); + pgprot_s2_device = __pgprot(s2_device_pgprot); + pgprot_hyp_device = __pgprot(hyp_device_pgprot); + + mem_types[MT_LOW_VECTORS].prot_l1 |= ecc_mask; + mem_types[MT_HIGH_VECTORS].prot_l1 |= ecc_mask; + mem_types[MT_MEMORY_RWX].prot_sect |= ecc_mask | cp->pmd; + mem_types[MT_MEMORY_RWX].prot_pte |= kern_pgprot; + mem_types[MT_MEMORY_RW].prot_sect |= ecc_mask | cp->pmd; + mem_types[MT_MEMORY_RW].prot_pte |= kern_pgprot; + mem_types[MT_MEMORY_DMA_READY].prot_pte |= kern_pgprot; + mem_types[MT_MEMORY_RWX_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; + } + pr_info("Memory policy: %sData cache %s\n", + ecc_mask ? "ECC enabled, " : "", 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_aligned(unsigned long sz, unsigned long align) +{ + void *ptr = __va(memblock_alloc(sz, align)); + memset(ptr, 0, sz); + return ptr; +} + +static void __init *early_alloc(unsigned long sz) +{ + return early_alloc_aligned(sz, sz); +} + +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 __map_init_section(pmd_t *pmd, unsigned long addr, + unsigned long end, phys_addr_t phys, + const struct mem_type *type) +{ + pmd_t *p = pmd; + +#ifndef CONFIG_ARM_LPAE + /* + * In classic MMU format, puds and pmds are folded in to + * the pgds. pmd_offset gives the PGD entry. PGDs refer to a + * group of L1 entries making up one logical pointer to + * an L2 table (2MB), where as PMDs refer to the individual + * L1 entries (1MB). Hence increment to get the correct + * offset for odd 1MB sections. + * (See arch/arm/include/asm/pgtable-2level.h) + */ + if (addr & SECTION_SIZE) + pmd++; +#endif + do { + *pmd = __pmd(phys | type->prot_sect); + phys += SECTION_SIZE; + } while (pmd++, addr += SECTION_SIZE, addr != end); + + flush_pmd_entry(p); +} + +static void __init alloc_init_pmd(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); + unsigned long next; + + do { + /* + * With LPAE, we must loop over to map + * all the pmds for the given range. + */ + next = pmd_addr_end(addr, end); + + /* + * Try a section mapping - addr, next and phys must all be + * aligned to a section boundary. + */ + if (type->prot_sect && + ((addr | next | phys) & ~SECTION_MASK) == 0) { + __map_init_section(pmd, addr, next, phys, type); + } else { + alloc_init_pte(pmd, addr, next, + __phys_to_pfn(phys), type); + } + + phys += next - addr; + + } while (pmd++, addr = next, addr != end); +} + +static void __init alloc_init_pud(pgd_t *pgd, unsigned long addr, + unsigned long end, phys_addr_t 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_pmd(pud, addr, next, phys, type); + phys += next - addr; + } while (pud++, addr = next, addr != end); +} + +#ifndef CONFIG_ARM_LPAE +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())) { + pr_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) { + pr_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) { + pr_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); +} +#endif /* !CONFIG_ARM_LPAE */ + +/* + * 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) { + pr_warn("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_START || md->virtual >= VMALLOC_END)) { + pr_warn("BUG: mapping for 0x%08llx at 0x%08lx out of vmalloc space\n", + (long long)__pfn_to_phys((u64)md->pfn), md->virtual); + } + + type = &mem_types[md->type]; + +#ifndef CONFIG_ARM_LPAE + /* + * Catch 36-bit addresses + */ + if (md->pfn >= 0x100000) { + create_36bit_mapping(md, type); + return; + } +#endif + + 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)) { + pr_warn("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) +{ + struct map_desc *md; + struct vm_struct *vm; + struct static_vm *svm; + + if (!nr) + return; + + svm = early_alloc_aligned(sizeof(*svm) * nr, __alignof__(*svm)); + + for (md = io_desc; nr; md++, nr--) { + create_mapping(md); + + vm = &svm->vm; + vm->addr = (void *)(md->virtual & PAGE_MASK); + vm->size = PAGE_ALIGN(md->length + (md->virtual & ~PAGE_MASK)); + vm->phys_addr = __pfn_to_phys(md->pfn); + vm->flags = VM_IOREMAP | VM_ARM_STATIC_MAPPING; + vm->flags |= VM_ARM_MTYPE(md->type); + vm->caller = iotable_init; + add_static_vm_early(svm++); + } +} + +void __init vm_reserve_area_early(unsigned long addr, unsigned long size, + void *caller) +{ + struct vm_struct *vm; + struct static_vm *svm; + + svm = early_alloc_aligned(sizeof(*svm), __alignof__(*svm)); + + vm = &svm->vm; + vm->addr = (void *)addr; + vm->size = size; + vm->flags = VM_IOREMAP | VM_ARM_EMPTY_MAPPING; + vm->caller = caller; + add_static_vm_early(svm); +} + +#ifndef CONFIG_ARM_LPAE + +/* + * The Linux PMD is made of two consecutive section entries covering 2MB + * (see definition in include/asm/pgtable-2level.h). However a call to + * create_mapping() may optimize static mappings by using individual + * 1MB section mappings. This leaves the actual PMD potentially half + * initialized if the top or bottom section entry isn't used, leaving it + * open to problems if a subsequent ioremap() or vmalloc() tries to use + * the virtual space left free by that unused section entry. + * + * Let's avoid the issue by inserting dummy vm entries covering the unused + * PMD halves once the static mappings are in place. + */ + +static void __init pmd_empty_section_gap(unsigned long addr) +{ + vm_reserve_area_early(addr, SECTION_SIZE, pmd_empty_section_gap); +} + +static void __init fill_pmd_gaps(void) +{ + struct static_vm *svm; + struct vm_struct *vm; + unsigned long addr, next = 0; + pmd_t *pmd; + + list_for_each_entry(svm, &static_vmlist, list) { + vm = &svm->vm; + addr = (unsigned long)vm->addr; + if (addr < next) + continue; + + /* + * Check if this vm starts on an odd section boundary. + * If so and the first section entry for this PMD is free + * then we block the corresponding virtual address. + */ + if ((addr & ~PMD_MASK) == SECTION_SIZE) { + pmd = pmd_off_k(addr); + if (pmd_none(*pmd)) + pmd_empty_section_gap(addr & PMD_MASK); + } + + /* + * Then check if this vm ends on an odd section boundary. + * If so and the second section entry for this PMD is empty + * then we block the corresponding virtual address. + */ + addr += vm->size; + if ((addr & ~PMD_MASK) == SECTION_SIZE) { + pmd = pmd_off_k(addr) + 1; + if (pmd_none(*pmd)) + pmd_empty_section_gap(addr); + } + + /* no need to look at any vm entry until we hit the next PMD */ + next = (addr + PMD_SIZE - 1) & PMD_MASK; + } +} + +#else +#define fill_pmd_gaps() do { } while (0) +#endif + +#if defined(CONFIG_PCI) && !defined(CONFIG_NEED_MACH_IO_H) +static void __init pci_reserve_io(void) +{ + struct static_vm *svm; + + svm = find_static_vm_vaddr((void *)PCI_IO_VIRT_BASE); + if (svm) + return; + + vm_reserve_area_early(PCI_IO_VIRT_BASE, SZ_2M, pci_reserve_io); +} +#else +#define pci_reserve_io() do { } while (0) +#endif + +#ifdef CONFIG_DEBUG_LL +void __init debug_ll_io_init(void) +{ + struct map_desc map; + + debug_ll_addr(&map.pfn, &map.virtual); + if (!map.pfn || !map.virtual) + return; + map.pfn = __phys_to_pfn(map.pfn); + map.virtual &= PAGE_MASK; + map.length = PAGE_SIZE; + map.type = MT_DEVICE; + iotable_init(&map, 1); +} +#endif + +static void * __initdata vmalloc_min = + (void *)(VMALLOC_END - (240 << 20) - VMALLOC_OFFSET); + +/* + * 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 240m. + */ +static int __init early_vmalloc(char *arg) +{ + unsigned long vmalloc_reserve = memparse(arg, NULL); + + if (vmalloc_reserve < SZ_16M) { + vmalloc_reserve = SZ_16M; + pr_warn("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); + pr_warn("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 __initdata = 0; + +void __init sanity_check_meminfo(void) +{ + phys_addr_t memblock_limit = 0; + int highmem = 0; + phys_addr_t vmalloc_limit = __pa(vmalloc_min - 1) + 1; + struct memblock_region *reg; + + for_each_memblock(memory, reg) { + phys_addr_t block_start = reg->base; + phys_addr_t block_end = reg->base + reg->size; + phys_addr_t size_limit = reg->size; + + if (reg->base >= vmalloc_limit) + highmem = 1; + else + size_limit = vmalloc_limit - reg->base; + + + if (!IS_ENABLED(CONFIG_HIGHMEM) || cache_is_vipt_aliasing()) { + + if (highmem) { + pr_notice("Ignoring RAM at %pa-%pa (!CONFIG_HIGHMEM)\n", + &block_start, &block_end); + memblock_remove(reg->base, reg->size); + continue; + } + + if (reg->size > size_limit) { + phys_addr_t overlap_size = reg->size - size_limit; + + pr_notice("Truncating RAM at %pa-%pa to -%pa", + &block_start, &block_end, &vmalloc_limit); + memblock_remove(vmalloc_limit, overlap_size); + block_end = vmalloc_limit; + } + } + + if (!highmem) { + if (block_end > arm_lowmem_limit) { + if (reg->size > size_limit) + arm_lowmem_limit = vmalloc_limit; + else + arm_lowmem_limit = block_end; + } + + /* + * Find the first non-pmd-aligned page, and point + * memblock_limit at it. This relies on rounding the + * limit down to be pmd-aligned, which happens at the + * end of this function. + * + * With this algorithm, the start or end of almost any + * bank can be non-pmd-aligned. The only exception is + * that the start of the bank 0 must be section- + * aligned, since otherwise memory would need to be + * allocated when mapping the start of bank 0, which + * occurs before any free memory is mapped. + */ + if (!memblock_limit) { + if (!IS_ALIGNED(block_start, PMD_SIZE)) + memblock_limit = block_start; + else if (!IS_ALIGNED(block_end, PMD_SIZE)) + memblock_limit = arm_lowmem_limit; + } + + } + } + + high_memory = __va(arm_lowmem_limit - 1) + 1; + + /* + * Round the memblock limit down to a pmd size. This + * helps to ensure that we will allocate memory from the + * last full pmd, which should be mapped. + */ + if (memblock_limit) + memblock_limit = round_down(memblock_limit, PMD_SIZE); + if (!memblock_limit) + memblock_limit = arm_lowmem_limit; + + memblock_set_current_limit(memblock_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 += PMD_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 + PMD_SIZE - 1) & PMD_MASK; +#endif + for ( ; addr < PAGE_OFFSET; addr += PMD_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 vmalloc region. + */ + for (addr = __phys_to_virt(end); + addr < VMALLOC_START; addr += PMD_SIZE) + pmd_clear(pmd_off_k(addr)); +} + +#ifdef CONFIG_ARM_LPAE +/* the first page is reserved for pgd */ +#define SWAPPER_PG_DIR_SIZE (PAGE_SIZE + \ + PTRS_PER_PGD * PTRS_PER_PMD * sizeof(pmd_t)) +#else +#define SWAPPER_PG_DIR_SIZE (PTRS_PER_PGD * sizeof(pgd_t)) +#endif + +/* + * 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), SWAPPER_PG_DIR_SIZE); + +#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 the device mappings. Since we clear out the page tables for all + * mappings above VMALLOC_START, 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(const struct machine_desc *mdesc) +{ + struct map_desc map; + unsigned long addr; + void *vectors; + + /* + * Allocate the vector page early. + */ + vectors = early_alloc(PAGE_SIZE * 2); + + early_trap_init(vectors); + + for (addr = VMALLOC_START; addr; addr += PMD_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)); + map.virtual = 0xffff0000; + map.length = PAGE_SIZE; +#ifdef CONFIG_KUSER_HELPERS + map.type = MT_HIGH_VECTORS; +#else + map.type = MT_LOW_VECTORS; +#endif + create_mapping(&map); + + if (!vectors_high()) { + map.virtual = 0; + map.length = PAGE_SIZE * 2; + map.type = MT_LOW_VECTORS; + create_mapping(&map); + } + + /* Now create a kernel read-only mapping */ + map.pfn += 1; + map.virtual = 0xffff0000 + PAGE_SIZE; + map.length = PAGE_SIZE; + 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(); + else + debug_ll_io_init(); + fill_pmd_gaps(); + + /* Reserve fixed i/o space in VMALLOC region */ + pci_reserve_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 + + early_pte_alloc(pmd_off_k(FIXADDR_START), FIXADDR_START, + _PAGE_KERNEL_TABLE); +} + +static void __init map_lowmem(void) +{ + struct memblock_region *reg; + phys_addr_t kernel_x_start = round_down(__pa(_stext), SECTION_SIZE); + phys_addr_t kernel_x_end = round_up(__pa(__init_end), SECTION_SIZE); + + /* 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; + + if (end < kernel_x_start) { + map.pfn = __phys_to_pfn(start); + map.virtual = __phys_to_virt(start); + map.length = end - start; + map.type = MT_MEMORY_RWX; + + create_mapping(&map); + } else if (start >= kernel_x_end) { + map.pfn = __phys_to_pfn(start); + map.virtual = __phys_to_virt(start); + map.length = end - start; + map.type = MT_MEMORY_RW; + + create_mapping(&map); + } else { + /* This better cover the entire kernel */ + if (start < kernel_x_start) { + map.pfn = __phys_to_pfn(start); + map.virtual = __phys_to_virt(start); + map.length = kernel_x_start - start; + map.type = MT_MEMORY_RW; + + create_mapping(&map); + } + + map.pfn = __phys_to_pfn(kernel_x_start); + map.virtual = __phys_to_virt(kernel_x_start); + map.length = kernel_x_end - kernel_x_start; + map.type = MT_MEMORY_RWX; + + create_mapping(&map); + + if (kernel_x_end < end) { + map.pfn = __phys_to_pfn(kernel_x_end); + map.virtual = __phys_to_virt(kernel_x_end); + map.length = end - kernel_x_end; + map.type = MT_MEMORY_RW; + + create_mapping(&map); + } + } + } +} + +#ifdef CONFIG_ARM_LPAE +/* + * early_paging_init() recreates boot time page table setup, allowing machines + * to switch over to a high (>4G) address space on LPAE systems + */ +void __init early_paging_init(const struct machine_desc *mdesc, + struct proc_info_list *procinfo) +{ + pmdval_t pmdprot = procinfo->__cpu_mm_mmu_flags; + unsigned long map_start, map_end; + pgd_t *pgd0, *pgdk; + pud_t *pud0, *pudk, *pud_start; + pmd_t *pmd0, *pmdk; + phys_addr_t phys; + int i; + + if (!(mdesc->init_meminfo)) + return; + + /* remap kernel code and data */ + map_start = init_mm.start_code & PMD_MASK; + map_end = ALIGN(init_mm.brk, PMD_SIZE); + + /* get a handle on things... */ + pgd0 = pgd_offset_k(0); + pud_start = pud0 = pud_offset(pgd0, 0); + pmd0 = pmd_offset(pud0, 0); + + pgdk = pgd_offset_k(map_start); + pudk = pud_offset(pgdk, map_start); + pmdk = pmd_offset(pudk, map_start); + + mdesc->init_meminfo(); + + /* Run the patch stub to update the constants */ + fixup_pv_table(&__pv_table_begin, + (&__pv_table_end - &__pv_table_begin) << 2); + + /* + * Cache cleaning operations for self-modifying code + * We should clean the entries by MVA but running a + * for loop over every pv_table entry pointer would + * just complicate the code. + */ + flush_cache_louis(); + dsb(ishst); + isb(); + + /* + * FIXME: This code is not architecturally compliant: we modify + * the mappings in-place, indeed while they are in use by this + * very same code. This may lead to unpredictable behaviour of + * the CPU. + * + * Even modifying the mappings in a separate page table does + * not resolve this. + * + * The architecture strongly recommends that when a mapping is + * changed, that it is changed by first going via an invalid + * mapping and back to the new mapping. This is to ensure that + * no TLB conflicts (caused by the TLB having more than one TLB + * entry match a translation) can occur. However, doing that + * here will result in unmapping the code we are running. + */ + pr_warn("WARNING: unsafe modification of in-place page tables - tainting kernel\n"); + add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK); + + /* + * Remap level 1 table. This changes the physical addresses + * used to refer to the level 2 page tables to the high + * physical address alias, leaving everything else the same. + */ + for (i = 0; i < PTRS_PER_PGD; pud0++, i++) { + set_pud(pud0, + __pud(__pa(pmd0) | PMD_TYPE_TABLE | L_PGD_SWAPPER)); + pmd0 += PTRS_PER_PMD; + } + + /* + * Remap the level 2 table, pointing the mappings at the high + * physical address alias of these pages. + */ + phys = __pa(map_start); + do { + *pmdk++ = __pmd(phys | pmdprot); + phys += PMD_SIZE; + } while (phys < map_end); + + /* + * Ensure that the above updates are flushed out of the cache. + * This is not strictly correct; on a system where the caches + * are coherent with each other, but the MMU page table walks + * may not be coherent, flush_cache_all() may be a no-op, and + * this will fail. + */ + flush_cache_all(); + + /* + * Re-write the TTBR values to point them at the high physical + * alias of the page tables. We expect __va() will work on + * cpu_get_pgd(), which returns the value of TTBR0. + */ + cpu_switch_mm(pgd0, &init_mm); + cpu_set_ttbr(1, __pa(pgd0) + TTBR1_OFFSET); + + /* Finally flush any stale TLB values. */ + local_flush_bp_all(); + local_flush_tlb_all(); +} + +#else + +void __init early_paging_init(const struct machine_desc *mdesc, + struct proc_info_list *procinfo) +{ + if (mdesc->init_meminfo) + mdesc->init_meminfo(); +} + +#endif + +/* + * 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(const struct machine_desc *mdesc) +{ + void *zero_page; + + build_mem_type_table(); + prepare_page_table(); + map_lowmem(); + dma_contiguous_remap(); + devicemaps_init(mdesc); + kmap_init(); + tcm_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); +} |