LXR linux/arch/mn10300/mm/cache.c

   1/* MN10300 Cache flushing routines
   2 *
   3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
   4 * Written by David Howells (dhowells@redhat.com)
   5 *
   6 * This program is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU General Public Licence
   8 * as published by the Free Software Foundation; either version
   9 * 2 of the Licence, or (at your option) any later version.
  10 */
  11#include <linux/module.h>
  12#include <linux/mm.h>
  13#include <linux/mman.h>
  14#include <linux/threads.h>
  15#include <asm/page.h>
  16#include <asm/pgtable.h>
  17#include <asm/processor.h>
  18#include <asm/cacheflush.h>
  19#include <asm/io.h>
  20#include <asm/uaccess.h>
  21
  22EXPORT_SYMBOL(mn10300_icache_inv);
  23EXPORT_SYMBOL(mn10300_dcache_inv);
  24EXPORT_SYMBOL(mn10300_dcache_inv_range);
  25EXPORT_SYMBOL(mn10300_dcache_inv_range2);
  26EXPORT_SYMBOL(mn10300_dcache_inv_page);
  27
  28#ifdef CONFIG_MN10300_CACHE_WBACK
  29EXPORT_SYMBOL(mn10300_dcache_flush);
  30EXPORT_SYMBOL(mn10300_dcache_flush_inv);
  31EXPORT_SYMBOL(mn10300_dcache_flush_inv_range);
  32EXPORT_SYMBOL(mn10300_dcache_flush_inv_range2);
  33EXPORT_SYMBOL(mn10300_dcache_flush_inv_page);
  34EXPORT_SYMBOL(mn10300_dcache_flush_range);
  35EXPORT_SYMBOL(mn10300_dcache_flush_range2);
  36EXPORT_SYMBOL(mn10300_dcache_flush_page);
  37#endif
  38
  39/*
  40 * write a page back from the dcache and invalidate the icache so that we can
  41 * run code from it that we've just written into it
  42 */
  43void flush_icache_page(struct vm_area_struct *vma, struct page *page)
  44{
  45        mn10300_dcache_flush_page(page_to_phys(page));
  46        mn10300_icache_inv();
  47}
  48EXPORT_SYMBOL(flush_icache_page);
  49
  50/*
  51 * write some code we've just written back from the dcache and invalidate the
  52 * icache so that we can run that code
  53 */
  54void flush_icache_range(unsigned long start, unsigned long end)
  55{
  56#ifdef CONFIG_MN10300_CACHE_WBACK
  57        unsigned long addr, size, off;
  58        struct page *page;
  59        pgd_t *pgd;
  60        pud_t *pud;
  61        pmd_t *pmd;
  62        pte_t *ppte, pte;
  63
  64        for (; start < end; start += size) {
  65                /* work out how much of the page to flush */
  66                off = start & (PAGE_SIZE - 1);
  67
  68                size = end - start;
  69                if (size > PAGE_SIZE - off)
  70                        size = PAGE_SIZE - off;
  71
  72                /* get the physical address the page is mapped to from the page
  73                 * tables */
  74                pgd = pgd_offset(current->mm, start);
  75                if (!pgd || !pgd_val(*pgd))
  76                        continue;
  77
  78                pud = pud_offset(pgd, start);
  79                if (!pud || !pud_val(*pud))
  80                        continue;
  81
  82                pmd = pmd_offset(pud, start);
  83                if (!pmd || !pmd_val(*pmd))
  84                        continue;
  85
  86                ppte = pte_offset_map(pmd, start);
  87                if (!ppte)
  88                        continue;
  89                pte = *ppte;
  90                pte_unmap(ppte);
  91
  92                if (pte_none(pte))
  93                        continue;
  94
  95                page = pte_page(pte);
  96                if (!page)
  97                        continue;
  98
  99                addr = page_to_phys(page);
 100
 101                /* flush the dcache and invalidate the icache coverage on that
 102                 * region */
 103                mn10300_dcache_flush_range2(addr + off, size);
 104        }
 105#endif
 106
 107        mn10300_icache_inv();
 108}
 109EXPORT_SYMBOL(flush_icache_range);
 110
 111/*
 112 * allow userspace to flush the instruction cache
 113 */
 114asmlinkage long sys_cacheflush(unsigned long start, unsigned long end)
 115{
 116        if (end < start)
 117                return -EINVAL;
 118
 119        flush_icache_range(start, end);
 120        return 0;
 121}
 122