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Diffstat (limited to 'arch/powerpc/mm/pgtable_64.c')
| -rw-r--r-- | arch/powerpc/mm/pgtable_64.c | 330 |
1 files changed, 330 insertions, 0 deletions
diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c new file mode 100644 index 00000000..249a0631 --- /dev/null +++ b/arch/powerpc/mm/pgtable_64.c @@ -0,0 +1,330 @@ +/* + * This file contains ioremap and related functions for 64-bit machines. + * + * Derived from arch/ppc64/mm/init.c + * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) + * + * Modifications by Paul Mackerras (PowerMac) (paulus@samba.org) + * 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 + * + * Dave Engebretsen <engebret@us.ibm.com> + * Rework for PPC64 port. + * + * 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/signal.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/string.h> +#include <linux/export.h> +#include <linux/types.h> +#include <linux/mman.h> +#include <linux/mm.h> +#include <linux/swap.h> +#include <linux/stddef.h> +#include <linux/vmalloc.h> +#include <linux/init.h> +#include <linux/bootmem.h> +#include <linux/memblock.h> +#include <linux/slab.h> + +#include <asm/pgalloc.h> +#include <asm/page.h> +#include <asm/prom.h> +#include <asm/io.h> +#include <asm/mmu_context.h> +#include <asm/pgtable.h> +#include <asm/mmu.h> +#include <asm/smp.h> +#include <asm/machdep.h> +#include <asm/tlb.h> +#include <asm/processor.h> +#include <asm/cputable.h> +#include <asm/sections.h> +#include <asm/abs_addr.h> +#include <asm/firmware.h> + +#include "mmu_decl.h" + +unsigned long ioremap_bot = IOREMAP_BASE; + + +#ifdef CONFIG_PPC_MMU_NOHASH +static void *early_alloc_pgtable(unsigned long size) +{ + void *pt; + + if (init_bootmem_done) + pt = __alloc_bootmem(size, size, __pa(MAX_DMA_ADDRESS)); + else + pt = __va(memblock_alloc_base(size, size, + __pa(MAX_DMA_ADDRESS))); + memset(pt, 0, size); + + return pt; +} +#endif /* CONFIG_PPC_MMU_NOHASH */ + +/* + * map_kernel_page currently only called by __ioremap + * map_kernel_page adds an entry to the ioremap page table + * and adds an entry to the HPT, possibly bolting it + */ +int map_kernel_page(unsigned long ea, unsigned long pa, int flags) +{ + pgd_t *pgdp; + pud_t *pudp; + pmd_t *pmdp; + pte_t *ptep; + + if (slab_is_available()) { + pgdp = pgd_offset_k(ea); + pudp = pud_alloc(&init_mm, pgdp, ea); + if (!pudp) + return -ENOMEM; + pmdp = pmd_alloc(&init_mm, pudp, ea); + if (!pmdp) + return -ENOMEM; + ptep = pte_alloc_kernel(pmdp, ea); + if (!ptep) + return -ENOMEM; + set_pte_at(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT, + __pgprot(flags))); + } else { +#ifdef CONFIG_PPC_MMU_NOHASH + /* Warning ! This will blow up if bootmem is not initialized + * which our ppc64 code is keen to do that, we'll need to + * fix it and/or be more careful + */ + pgdp = pgd_offset_k(ea); +#ifdef PUD_TABLE_SIZE + if (pgd_none(*pgdp)) { + pudp = early_alloc_pgtable(PUD_TABLE_SIZE); + BUG_ON(pudp == NULL); + pgd_populate(&init_mm, pgdp, pudp); + } +#endif /* PUD_TABLE_SIZE */ + pudp = pud_offset(pgdp, ea); + if (pud_none(*pudp)) { + pmdp = early_alloc_pgtable(PMD_TABLE_SIZE); + BUG_ON(pmdp == NULL); + pud_populate(&init_mm, pudp, pmdp); + } + pmdp = pmd_offset(pudp, ea); + if (!pmd_present(*pmdp)) { + ptep = early_alloc_pgtable(PAGE_SIZE); + BUG_ON(ptep == NULL); + pmd_populate_kernel(&init_mm, pmdp, ptep); + } + ptep = pte_offset_kernel(pmdp, ea); + set_pte_at(&init_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT, + __pgprot(flags))); +#else /* CONFIG_PPC_MMU_NOHASH */ + /* + * If the mm subsystem is not fully up, we cannot create a + * linux page table entry for this mapping. Simply bolt an + * entry in the hardware page table. + * + */ + if (htab_bolt_mapping(ea, ea + PAGE_SIZE, pa, flags, + mmu_io_psize, mmu_kernel_ssize)) { + printk(KERN_ERR "Failed to do bolted mapping IO " + "memory at %016lx !\n", pa); + return -ENOMEM; + } +#endif /* !CONFIG_PPC_MMU_NOHASH */ + } + return 0; +} + + +/** + * __ioremap_at - Low level function to establish the page tables + * for an IO mapping + */ +void __iomem * __ioremap_at(phys_addr_t pa, void *ea, unsigned long size, + unsigned long flags) +{ + unsigned long i; + + /* 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; + + /* We don't support the 4K PFN hack with ioremap */ + if (flags & _PAGE_4K_PFN) + return NULL; + + WARN_ON(pa & ~PAGE_MASK); + WARN_ON(((unsigned long)ea) & ~PAGE_MASK); + WARN_ON(size & ~PAGE_MASK); + + for (i = 0; i < size; i += PAGE_SIZE) + if (map_kernel_page((unsigned long)ea+i, pa+i, flags)) + return NULL; + + return (void __iomem *)ea; +} + +/** + * __iounmap_from - Low level function to tear down the page tables + * for an IO mapping. This is used for mappings that + * are manipulated manually, like partial unmapping of + * PCI IOs or ISA space. + */ +void __iounmap_at(void *ea, unsigned long size) +{ + WARN_ON(((unsigned long)ea) & ~PAGE_MASK); + WARN_ON(size & ~PAGE_MASK); + + unmap_kernel_range((unsigned long)ea, size); +} + +void __iomem * __ioremap_caller(phys_addr_t addr, unsigned long size, + unsigned long flags, void *caller) +{ + phys_addr_t paligned; + void __iomem *ret; + + /* + * Choose an address to map it to. + * Once the imalloc system is running, we use it. + * Before that, we map using addresses going + * up from ioremap_bot. imalloc will use + * the addresses from ioremap_bot through + * IMALLOC_END + * + */ + paligned = addr & PAGE_MASK; + size = PAGE_ALIGN(addr + size) - paligned; + + if ((size == 0) || (paligned == 0)) + return NULL; + + if (mem_init_done) { + struct vm_struct *area; + + area = __get_vm_area_caller(size, VM_IOREMAP, + ioremap_bot, IOREMAP_END, + caller); + if (area == NULL) + return NULL; + + area->phys_addr = paligned; + ret = __ioremap_at(paligned, area->addr, size, flags); + if (!ret) + vunmap(area->addr); + } else { + ret = __ioremap_at(paligned, (void *)ioremap_bot, size, flags); + if (ret) + ioremap_bot += size; + } + + if (ret) + ret += addr & ~PAGE_MASK; + return ret; +} + +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(phys_addr_t addr, unsigned long size) +{ + unsigned long flags = _PAGE_NO_CACHE | _PAGE_GUARDED; + void *caller = __builtin_return_address(0); + + if (ppc_md.ioremap) + return ppc_md.ioremap(addr, size, flags, caller); + return __ioremap_caller(addr, size, flags, caller); +} + +void __iomem * ioremap_wc(phys_addr_t addr, unsigned long size) +{ + unsigned long flags = _PAGE_NO_CACHE; + void *caller = __builtin_return_address(0); + + if (ppc_md.ioremap) + return ppc_md.ioremap(addr, size, flags, caller); + return __ioremap_caller(addr, size, flags, caller); +} + +void __iomem * ioremap_prot(phys_addr_t addr, unsigned long size, + unsigned long flags) +{ + void *caller = __builtin_return_address(0); + + /* writeable implies dirty for kernel addresses */ + if (flags & _PAGE_RW) + flags |= _PAGE_DIRTY; + + /* 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 + + if (ppc_md.ioremap) + return ppc_md.ioremap(addr, size, flags, caller); + return __ioremap_caller(addr, size, flags, caller); +} + + +/* + * Unmap an IO region and remove it from imalloc'd list. + * Access to IO memory should be serialized by driver. + */ +void __iounmap(volatile void __iomem *token) +{ + void *addr; + + if (!mem_init_done) + return; + + addr = (void *) ((unsigned long __force) + PCI_FIX_ADDR(token) & PAGE_MASK); + if ((unsigned long)addr < ioremap_bot) { + printk(KERN_WARNING "Attempt to iounmap early bolted mapping" + " at 0x%p\n", addr); + return; + } + vunmap(addr); +} + +void iounmap(volatile void __iomem *token) +{ + if (ppc_md.iounmap) + ppc_md.iounmap(token); + else + __iounmap(token); +} + +EXPORT_SYMBOL(ioremap); +EXPORT_SYMBOL(ioremap_wc); +EXPORT_SYMBOL(ioremap_prot); +EXPORT_SYMBOL(__ioremap); +EXPORT_SYMBOL(__ioremap_at); +EXPORT_SYMBOL(iounmap); +EXPORT_SYMBOL(__iounmap); +EXPORT_SYMBOL(__iounmap_at); |