include/asm-cris/arch-v10/mmu.h

   1 /*
   2  * CRIS MMU constants and PTE layout
   3  */
   4
   5 #ifndef _CRIS_ARCH_MMU_H
   6 #define _CRIS_ARCH_MMU_H
   7
   8 /* type used in struct mm to couple an MMU context to an active mm */
   9
  10 typedef unsigned int mm_context_t;
  11
  12 /* kernel memory segments */
  13
  14 #define KSEG_F 0xf0000000UL
  15 #define KSEG_E 0xe0000000UL
  16 #define KSEG_D 0xd0000000UL
  17 #define KSEG_C 0xc0000000UL
  18 #define KSEG_B 0xb0000000UL
  19 #define KSEG_A 0xa0000000UL
  20 #define KSEG_9 0x90000000UL
  21 #define KSEG_8 0x80000000UL
  22 #define KSEG_7 0x70000000UL
  23 #define KSEG_6 0x60000000UL
  24 #define KSEG_5 0x50000000UL
  25 #define KSEG_4 0x40000000UL
  26 #define KSEG_3 0x30000000UL
  27 #define KSEG_2 0x20000000UL
  28 #define KSEG_1 0x10000000UL
  29 #define KSEG_0 0x00000000UL
  30
  31 /* CRIS PTE bits (see R_TLB_LO in the register description)
  32  *
  33  *   Bit:  31-13 12-------4    3        2       1       0
  34  *         ________________________________________________
  35  *        | pfn | reserved | global | valid | kernel | we  |
  36  *        |_____|__________|________|_______|________|_____|
  37  *
  38  * (pfn = physical frame number)
  39  */
  40
  41 /* Real HW-based PTE bits. We use some synonym names so that
  42  * things become less confusing in combination with the SW-based
  43  * bits further below.
  44  *
  45  */
  46
  47 #define _PAGE_WE           (1<<0) /* page is write-enabled */
  48 #define _PAGE_SILENT_WRITE (1<<0) /* synonym */
  49 #define _PAGE_KERNEL       (1<<1) /* page is kernel only */
  50 #define _PAGE_VALID        (1<<2) /* page is valid */
  51 #define _PAGE_SILENT_READ  (1<<2) /* synonym */
  52 #define _PAGE_GLOBAL       (1<<3) /* global page - context is ignored */
  53
  54 /* Bits the HW doesn't care about but the kernel uses them in SW */
  55
  56 #define _PAGE_PRESENT   (1<<4)  /* page present in memory */
  57 #define _PAGE_FILE      (1<<5)  /* set: pagecache, unset: swap (when !PRESENT) */
  58 #define _PAGE_ACCESSED  (1<<5)  /* simulated in software using valid bit */
  59 #define _PAGE_MODIFIED  (1<<6)  /* simulated in software using we bit */
  60 #define _PAGE_READ      (1<<7)  /* read-enabled */
  61 #define _PAGE_WRITE     (1<<8)  /* write-enabled */
  62
  63 /* Define some higher level generic page attributes. */
  64
  65 #define __READABLE      (_PAGE_READ | _PAGE_SILENT_READ | _PAGE_ACCESSED)
  66 #define __WRITEABLE     (_PAGE_WRITE | _PAGE_SILENT_WRITE | _PAGE_MODIFIED)
  67
  68 #define _PAGE_TABLE     (_PAGE_PRESENT | __READABLE | __WRITEABLE)
  69 #define _PAGE_CHG_MASK  (PAGE_MASK | _PAGE_ACCESSED | _PAGE_MODIFIED)
  70
  71 #define PAGE_NONE       __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED)
  72 #define PAGE_SHARED     __pgprot(_PAGE_PRESENT | __READABLE | _PAGE_WRITE | \
  73                                  _PAGE_ACCESSED)
  74 #define PAGE_COPY       __pgprot(_PAGE_PRESENT | __READABLE)  // | _PAGE_COW
  75 #define PAGE_READONLY   __pgprot(_PAGE_PRESENT | __READABLE)
  76 #define PAGE_KERNEL     __pgprot(_PAGE_GLOBAL | _PAGE_KERNEL | \
  77                                  _PAGE_PRESENT | __READABLE | __WRITEABLE)
  78 #define _KERNPG_TABLE   (_PAGE_TABLE | _PAGE_KERNEL)
  79
  80 /*
  81  * CRIS can't do page protection for execute, and considers read the same.
  82  * Also, write permissions imply read permissions. This is the closest we can
  83  * get..
  84  */
  85
  86 #define __P000  PAGE_NONE
  87 #define __P001  PAGE_READONLY
  88 #define __P010  PAGE_COPY
  89 #define __P011  PAGE_COPY
  90 #define __P100  PAGE_READONLY
  91 #define __P101  PAGE_READONLY
  92 #define __P110  PAGE_COPY
  93 #define __P111  PAGE_COPY
  94
  95 #define __S000  PAGE_NONE
  96 #define __S001  PAGE_READONLY
  97 #define __S010  PAGE_SHARED
  98 #define __S011  PAGE_SHARED
  99 #define __S100  PAGE_READONLY
 100 #define __S101  PAGE_READONLY
 101 #define __S110  PAGE_SHARED
 102 #define __S111  PAGE_SHARED
 103
 104 #define PTE_FILE_MAX_BITS       26
 105
 106 #endif