uncached.c 940 B

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