LXR linux/arch/sh/mm/uncached.c

   1#include <linux/init.h>
   2#include <linux/module.h>
   3#include <asm/sizes.h>
   4#include <asm/page.h>
   5#include <asm/addrspace.h>
   6
   7/*
   8 * This is the offset of the uncached section from its cached alias.
   9 *
  10 * Legacy platforms handle trivial transitions between cached and
  11 * uncached segments by making use of the 1:1 mapping relationship in
  12 * 512MB lowmem, others via a special uncached mapping.
  13 *
  14 * Default value only valid in 29 bit mode, in 32bit mode this will be
  15 * updated by the early PMB initialization code.
  16 */
  17unsigned long cached_to_uncached = SZ_512M;
  18unsigned long uncached_size = SZ_512M;
  19unsigned long uncached_start, uncached_end;
  20EXPORT_SYMBOL(uncached_start);
  21EXPORT_SYMBOL(uncached_end);
  22
  23int virt_addr_uncached(unsigned long kaddr)
  24{
  25        return (kaddr >= uncached_start) && (kaddr < uncached_end);
  26}
  27EXPORT_SYMBOL(virt_addr_uncached);
  28
  29void __init uncached_init(void)
  30{
  31#if defined(CONFIG_29BIT) || !defined(CONFIG_MMU)
  32        uncached_start = P2SEG;
  33#else
  34        uncached_start = memory_end;
  35#endif
  36        uncached_end = uncached_start + uncached_size;
  37}
  38
  39void __init uncached_resize(unsigned long size)
  40{
  41        uncached_size = size;
  42        uncached_end = uncached_start + uncached_size;
  43}
  44