diff options
Diffstat (limited to 'kernel/arch/powerpc/mm/pgtable_32.c')
| -rw-r--r-- | kernel/arch/powerpc/mm/pgtable_32.c | 466 |
1 files changed, 466 insertions, 0 deletions
diff --git a/kernel/arch/powerpc/mm/pgtable_32.c b/kernel/arch/powerpc/mm/pgtable_32.c new file mode 100644 index 000000000..7692d1bb1 --- /dev/null +++ b/kernel/arch/powerpc/mm/pgtable_32.c @@ -0,0 +1,466 @@ +/* + * This file contains the routines setting up the linux page tables. + * -- paulus + * + * Derived from arch/ppc/mm/init.c: + * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) + * + * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) + * and Cort Dougan (PReP) (cort@cs.nmt.edu) + * Copyright (C) 1996 Paul Mackerras + * + * Derived from "arch/i386/mm/init.c" + * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/types.h> +#include <linux/mm.h> +#include <linux/vmalloc.h> +#include <linux/init.h> +#include <linux/highmem.h> +#include <linux/memblock.h> +#include <linux/slab.h> + +#include <asm/pgtable.h> +#include <asm/pgalloc.h> +#include <asm/fixmap.h> +#include <asm/io.h> +#include <asm/setup.h> + +#include "mmu_decl.h" + +unsigned long ioremap_base; +unsigned long ioremap_bot; +EXPORT_SYMBOL(ioremap_bot); /* aka VMALLOC_END */ + +#ifdef CONFIG_6xx +#define HAVE_BATS 1 +#endif + +#if defined(CONFIG_FSL_BOOKE) +#define HAVE_TLBCAM 1 +#endif + +extern char etext[], _stext[]; + +#ifdef HAVE_BATS +extern phys_addr_t v_mapped_by_bats(unsigned long va); +extern unsigned long p_mapped_by_bats(phys_addr_t pa); +#else /* !HAVE_BATS */ +#define v_mapped_by_bats(x) (0UL) +#define p_mapped_by_bats(x) (0UL) +#endif /* HAVE_BATS */ + +#ifdef HAVE_TLBCAM +extern phys_addr_t v_mapped_by_tlbcam(unsigned long va); +extern unsigned long p_mapped_by_tlbcam(phys_addr_t pa); +#else /* !HAVE_TLBCAM */ +#define v_mapped_by_tlbcam(x) (0UL) +#define p_mapped_by_tlbcam(x) (0UL) +#endif /* HAVE_TLBCAM */ + +#define PGDIR_ORDER (32 + PGD_T_LOG2 - PGDIR_SHIFT) + +#ifndef CONFIG_PPC_4K_PAGES +static struct kmem_cache *pgtable_cache; + +void pgtable_cache_init(void) +{ + pgtable_cache = kmem_cache_create("PGDIR cache", 1 << PGDIR_ORDER, + 1 << PGDIR_ORDER, 0, NULL); + if (pgtable_cache == NULL) + panic("Couldn't allocate pgtable caches"); +} +#endif + +pgd_t *pgd_alloc(struct mm_struct *mm) +{ + pgd_t *ret; + + /* pgdir take page or two with 4K pages and a page fraction otherwise */ +#ifndef CONFIG_PPC_4K_PAGES + ret = kmem_cache_alloc(pgtable_cache, GFP_KERNEL | __GFP_ZERO); +#else + ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO, + PGDIR_ORDER - PAGE_SHIFT); +#endif + return ret; +} + +void pgd_free(struct mm_struct *mm, pgd_t *pgd) +{ +#ifndef CONFIG_PPC_4K_PAGES + kmem_cache_free(pgtable_cache, (void *)pgd); +#else + free_pages((unsigned long)pgd, PGDIR_ORDER - PAGE_SHIFT); +#endif +} + +__init_refok pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address) +{ + pte_t *pte; + + if (slab_is_available()) { + pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO); + } else { + pte = __va(memblock_alloc(PAGE_SIZE, PAGE_SIZE)); + if (pte) + clear_page(pte); + } + return pte; +} + +pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address) +{ + struct page *ptepage; + + gfp_t flags = GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO; + + ptepage = alloc_pages(flags, 0); + if (!ptepage) + return NULL; + if (!pgtable_page_ctor(ptepage)) { + __free_page(ptepage); + return NULL; + } + return ptepage; +} + +void __iomem * +ioremap(phys_addr_t addr, unsigned long size) +{ + return __ioremap_caller(addr, size, _PAGE_NO_CACHE | _PAGE_GUARDED, + __builtin_return_address(0)); +} +EXPORT_SYMBOL(ioremap); + +void __iomem * +ioremap_wc(phys_addr_t addr, unsigned long size) +{ + return __ioremap_caller(addr, size, _PAGE_NO_CACHE, + __builtin_return_address(0)); +} +EXPORT_SYMBOL(ioremap_wc); + +void __iomem * +ioremap_prot(phys_addr_t addr, unsigned long size, unsigned long flags) +{ + /* writeable implies dirty for kernel addresses */ + if ((flags & (_PAGE_RW | _PAGE_RO)) != _PAGE_RO) + flags |= _PAGE_DIRTY | _PAGE_HWWRITE; + + /* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */ + flags &= ~(_PAGE_USER | _PAGE_EXEC); + +#ifdef _PAGE_BAP_SR + /* _PAGE_USER contains _PAGE_BAP_SR on BookE using the new PTE format + * which means that we just cleared supervisor access... oops ;-) This + * restores it + */ + flags |= _PAGE_BAP_SR; +#endif + + return __ioremap_caller(addr, size, flags, __builtin_return_address(0)); +} +EXPORT_SYMBOL(ioremap_prot); + +void __iomem * +__ioremap(phys_addr_t addr, unsigned long size, unsigned long flags) +{ + return __ioremap_caller(addr, size, flags, __builtin_return_address(0)); +} + +void __iomem * +__ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags, + void *caller) +{ + unsigned long v, i; + phys_addr_t p; + int err; + + /* Make sure we have the base flags */ + if ((flags & _PAGE_PRESENT) == 0) + flags |= pgprot_val(PAGE_KERNEL); + + /* Non-cacheable page cannot be coherent */ + if (flags & _PAGE_NO_CACHE) + flags &= ~_PAGE_COHERENT; + + /* + * Choose an address to map it to. + * Once the vmalloc system is running, we use it. + * Before then, we use space going down from ioremap_base + * (ioremap_bot records where we're up to). + */ + p = addr & PAGE_MASK; + size = PAGE_ALIGN(addr + size) - p; + + /* + * If the address lies within the first 16 MB, assume it's in ISA + * memory space + */ + if (p < 16*1024*1024) + p += _ISA_MEM_BASE; + +#ifndef CONFIG_CRASH_DUMP + /* + * Don't allow anybody to remap normal RAM that we're using. + * mem_init() sets high_memory so only do the check after that. + */ + if (slab_is_available() && (p < virt_to_phys(high_memory)) && + !(__allow_ioremap_reserved && memblock_is_region_reserved(p, size))) { + printk("__ioremap(): phys addr 0x%llx is RAM lr %ps\n", + (unsigned long long)p, __builtin_return_address(0)); + return NULL; + } +#endif + + if (size == 0) + return NULL; + + /* + * Is it already mapped? Perhaps overlapped by a previous + * BAT mapping. If the whole area is mapped then we're done, + * otherwise remap it since we want to keep the virt addrs for + * each request contiguous. + * + * We make the assumption here that if the bottom and top + * of the range we want are mapped then it's mapped to the + * same virt address (and this is contiguous). + * -- Cort + */ + if ((v = p_mapped_by_bats(p)) /*&& p_mapped_by_bats(p+size-1)*/ ) + goto out; + + if ((v = p_mapped_by_tlbcam(p))) + goto out; + + if (slab_is_available()) { + struct vm_struct *area; + area = get_vm_area_caller(size, VM_IOREMAP, caller); + if (area == 0) + return NULL; + area->phys_addr = p; + v = (unsigned long) area->addr; + } else { + v = (ioremap_bot -= size); + } + + /* + * Should check if it is a candidate for a BAT mapping + */ + + err = 0; + for (i = 0; i < size && err == 0; i += PAGE_SIZE) + err = map_page(v+i, p+i, flags); + if (err) { + if (slab_is_available()) + vunmap((void *)v); + return NULL; + } + +out: + return (void __iomem *) (v + ((unsigned long)addr & ~PAGE_MASK)); +} +EXPORT_SYMBOL(__ioremap); + +void iounmap(volatile void __iomem *addr) +{ + /* + * If mapped by BATs then there is nothing to do. + * Calling vfree() generates a benign warning. + */ + if (v_mapped_by_bats((unsigned long)addr)) return; + + if (addr > high_memory && (unsigned long) addr < ioremap_bot) + vunmap((void *) (PAGE_MASK & (unsigned long)addr)); +} +EXPORT_SYMBOL(iounmap); + +int map_page(unsigned long va, phys_addr_t pa, int flags) +{ + pmd_t *pd; + pte_t *pg; + int err = -ENOMEM; + + /* Use upper 10 bits of VA to index the first level map */ + pd = pmd_offset(pud_offset(pgd_offset_k(va), va), va); + /* Use middle 10 bits of VA to index the second-level map */ + pg = pte_alloc_kernel(pd, va); + if (pg != 0) { + err = 0; + /* The PTE should never be already set nor present in the + * hash table + */ + BUG_ON((pte_val(*pg) & (_PAGE_PRESENT | _PAGE_HASHPTE)) && + flags); + set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT, + __pgprot(flags))); + } + smp_wmb(); + return err; +} + +/* + * Map in a chunk of physical memory starting at start. + */ +void __init __mapin_ram_chunk(unsigned long offset, unsigned long top) +{ + unsigned long v, s, f; + phys_addr_t p; + int ktext; + + s = offset; + v = PAGE_OFFSET + s; + p = memstart_addr + s; + for (; s < top; s += PAGE_SIZE) { + ktext = ((char *) v >= _stext && (char *) v < etext); + f = ktext ? pgprot_val(PAGE_KERNEL_TEXT) : pgprot_val(PAGE_KERNEL); + map_page(v, p, f); +#ifdef CONFIG_PPC_STD_MMU_32 + if (ktext) + hash_preload(&init_mm, v, 0, 0x300); +#endif + v += PAGE_SIZE; + p += PAGE_SIZE; + } +} + +void __init mapin_ram(void) +{ + unsigned long s, top; + +#ifndef CONFIG_WII + top = total_lowmem; + s = mmu_mapin_ram(top); + __mapin_ram_chunk(s, top); +#else + if (!wii_hole_size) { + s = mmu_mapin_ram(total_lowmem); + __mapin_ram_chunk(s, total_lowmem); + } else { + top = wii_hole_start; + s = mmu_mapin_ram(top); + __mapin_ram_chunk(s, top); + + top = memblock_end_of_DRAM(); + s = wii_mmu_mapin_mem2(top); + __mapin_ram_chunk(s, top); + } +#endif +} + +/* Scan the real Linux page tables and return a PTE pointer for + * a virtual address in a context. + * Returns true (1) if PTE was found, zero otherwise. The pointer to + * the PTE pointer is unmodified if PTE is not found. + */ +int +get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep, pmd_t **pmdp) +{ + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + pte_t *pte; + int retval = 0; + + pgd = pgd_offset(mm, addr & PAGE_MASK); + if (pgd) { + pud = pud_offset(pgd, addr & PAGE_MASK); + if (pud && pud_present(*pud)) { + pmd = pmd_offset(pud, addr & PAGE_MASK); + if (pmd_present(*pmd)) { + pte = pte_offset_map(pmd, addr & PAGE_MASK); + if (pte) { + retval = 1; + *ptep = pte; + if (pmdp) + *pmdp = pmd; + /* XXX caller needs to do pte_unmap, yuck */ + } + } + } + } + return(retval); +} + +#ifdef CONFIG_DEBUG_PAGEALLOC + +static int __change_page_attr(struct page *page, pgprot_t prot) +{ + pte_t *kpte; + pmd_t *kpmd; + unsigned long address; + + BUG_ON(PageHighMem(page)); + address = (unsigned long)page_address(page); + + if (v_mapped_by_bats(address) || v_mapped_by_tlbcam(address)) + return 0; + if (!get_pteptr(&init_mm, address, &kpte, &kpmd)) + return -EINVAL; + __set_pte_at(&init_mm, address, kpte, mk_pte(page, prot), 0); + wmb(); + flush_tlb_page(NULL, address); + pte_unmap(kpte); + + return 0; +} + +/* + * Change the page attributes of an page in the linear mapping. + * + * THIS CONFLICTS WITH BAT MAPPINGS, DEBUG USE ONLY + */ +static int change_page_attr(struct page *page, int numpages, pgprot_t prot) +{ + int i, err = 0; + unsigned long flags; + + local_irq_save(flags); + for (i = 0; i < numpages; i++, page++) { + err = __change_page_attr(page, prot); + if (err) + break; + } + local_irq_restore(flags); + return err; +} + + +void __kernel_map_pages(struct page *page, int numpages, int enable) +{ + if (PageHighMem(page)) + return; + + change_page_attr(page, numpages, enable ? PAGE_KERNEL : __pgprot(0)); +} +#endif /* CONFIG_DEBUG_PAGEALLOC */ + +static int fixmaps; + +void __set_fixmap (enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags) +{ + unsigned long address = __fix_to_virt(idx); + + if (idx >= __end_of_fixed_addresses) { + BUG(); + return; + } + + map_page(address, phys, pgprot_val(flags)); + fixmaps++; +} + +void __this_fixmap_does_not_exist(void) +{ + WARN_ON(1); +} |