arch/riscv/include/asm/pgtable-bits.h

   1 /*
   2  * Copyright (C) 2012 Regents of the University of California
   3  *
   4  *   This program is free software; you can redistribute it and/or
   5  *   modify it under the terms of the GNU General Public License
   6  *   as published by the Free Software Foundation, version 2.
   7  *
   8  *   This program is distributed in the hope that it will be useful,
   9  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  *   GNU General Public License for more details.
  12  */
  13
  14 #ifndef _ASM_RISCV_PGTABLE_BITS_H
  15 #define _ASM_RISCV_PGTABLE_BITS_H
  16
  17 /*
  18  * PTE format:
  19  * | XLEN-1  10 | 9             8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
  20  *       PFN      reserved for SW   D   A   G   U   X   W   R   V
  21  */
  22
  23 #define _PAGE_ACCESSED_OFFSET 6
  24
  25 #define _PAGE_PRESENT   (1 << 0)
  26 #define _PAGE_READ      (1 << 1)    /* Readable */
  27 #define _PAGE_WRITE     (1 << 2)    /* Writable */
  28 #define _PAGE_EXEC      (1 << 3)    /* Executable */
  29 #define _PAGE_USER      (1 << 4)    /* User */
  30 #define _PAGE_GLOBAL    (1 << 5)    /* Global */
  31 #define _PAGE_ACCESSED  (1 << 6)    /* Set by hardware on any access */
  32 #define _PAGE_DIRTY     (1 << 7)    /* Set by hardware on any write */
  33 #define _PAGE_SOFT      (1 << 8)    /* Reserved for software */
  34
  35 #define _PAGE_SPECIAL   _PAGE_SOFT
  36 #define _PAGE_TABLE     _PAGE_PRESENT
  37
  38 #define _PAGE_PFN_SHIFT 10
  39
  40 /* Set of bits to preserve across pte_modify() */
  41 #define _PAGE_CHG_MASK  (~(unsigned long)(_PAGE_PRESENT | _PAGE_READ |  \
  42                                           _PAGE_WRITE | _PAGE_EXEC |    \
  43                                           _PAGE_USER | _PAGE_GLOBAL))
  44
  45 /* Advertise support for _PAGE_SPECIAL */
  46 #define __HAVE_ARCH_PTE_SPECIAL
  47
  48 #endif /* _ASM_RISCV_PGTABLE_BITS_H */