pgtable-bits.h 1.0 KB

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  1. /*
  2. * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
  3. * Copyright (C) 2009 Wind River Systems Inc
  4. *
  5. * This file is subject to the terms and conditions of the GNU General Public
  6. * License. See the file "COPYING" in the main directory of this archive
  7. * for more details.
  8. */
  9. #ifndef _ASM_NIOS2_PGTABLE_BITS_H
  10. #define _ASM_NIOS2_PGTABLE_BITS_H
  11. /*
  12. * These are actual hardware defined protection bits in the tlbacc register
  13. * which looks like this:
  14. *
  15. * 31 30 ... 26 25 24 23 22 21 20 19 18 ... 1 0
  16. * ignored........ C R W X G PFN............
  17. */
  18. #define _PAGE_GLOBAL (1<<20)
  19. #define _PAGE_EXEC (1<<21)
  20. #define _PAGE_WRITE (1<<22)
  21. #define _PAGE_READ (1<<23)
  22. #define _PAGE_CACHED (1<<24) /* C: data access cacheable */
  23. /*
  24. * Software defined bits. They are ignored by the hardware and always read back
  25. * as zero, but can be written as non-zero.
  26. */
  27. #define _PAGE_PRESENT (1<<25) /* PTE contains a translation */
  28. #define _PAGE_ACCESSED (1<<26) /* page referenced */
  29. #define _PAGE_DIRTY (1<<27) /* dirty page */
  30. #endif /* _ASM_NIOS2_PGTABLE_BITS_H */