arch/sh/mm/uncached.c

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