LXR linux-bk/include/asm-parisc/mmu.h

   1/*
   2 * parisc mmu structures 
   3 */
   4
   5#ifndef _PARISC_MMU_H_
   6#define _PARISC_MMU_H_
   7
   8#ifndef __ASSEMBLY__
   9
  10/* Default "unsigned long" context */
  11typedef unsigned long mm_context_t;
  12
  13/* Hardware Page Table Entry */
  14typedef struct _PTE {
  15        unsigned long v:1;      /* Entry is valid */
  16        unsigned long tag:31;   /* Unique Tag */
  17
  18        unsigned long r:1;      /* referenced */
  19        unsigned long os_1:1;   /*  */
  20        unsigned long t:1;      /* page reference trap */
  21        unsigned long d:1;      /* dirty */
  22        unsigned long b:1;      /* break */
  23        unsigned long type:3;   /* access type */
  24        unsigned long pl1:2;    /* PL1 (execute) */
  25        unsigned long pl2:2;    /* PL2 (write) */
  26        unsigned long u:1;      /* uncacheable */
  27        unsigned long id:1;     /* access id */
  28        unsigned long os_2:1;   /*  */
  29
  30        unsigned long os_3:3;   /*  */
  31        unsigned long res_1:4;  /*  */
  32        unsigned long phys:20;  /* physical page number */
  33        unsigned long os_4:2;   /*  */
  34        unsigned long res_2:3;  /*  */
  35
  36        unsigned long next;     /* pointer to next page */
  37} PTE; 
  38
  39/*
  40 * Simulated two-level MMU.  This structure is used by the kernel
  41 * to keep track of MMU mappings and is used to update/maintain
  42 * the hardware HASH table which is really a cache of mappings.
  43 *
  44 * The simulated structures mimic the hardware available on other
  45 * platforms, notably the 80x86 and 680x0.
  46 */
  47
  48typedef struct _pte {
  49        unsigned long page_num:20;
  50        unsigned long flags:12;         /* Page flags (some unused bits) */
  51} pte;
  52
  53#define PD_SHIFT (10+12)                /* Page directory */
  54#define PD_MASK  0x02FF
  55#define PT_SHIFT (12)                   /* Page Table */
  56#define PT_MASK  0x02FF
  57#define PG_SHIFT (12)                   /* Page Entry */
  58
  59/* MMU context */
  60
  61typedef struct _MMU_context {
  62        long    pid[4];
  63        pte     **pmap;         /* Two-level page-map structure */
  64} MMU_context;
  65
  66#endif /* __ASSEMBLY__ */
  67
  68#endif /* _PARISC_MMU_H_ */
  69