arch/sparc/include/asm/pgtsrmmu.h

   1 /*
   2  * pgtsrmmu.h:  SRMMU page table defines and code.
   3  *
   4  * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
   5  */
   6
   7 #ifndef _SPARC_PGTSRMMU_H
   8 #define _SPARC_PGTSRMMU_H
   9
  10 #include <asm/page.h>
  11
  12 #ifdef __ASSEMBLY__
  13 #include <asm/thread_info.h>    /* TI_UWINMASK for WINDOW_FLUSH */
  14 #endif
  15
  16 /* Number of contexts is implementation-dependent; 64k is the most we support */
  17 #define SRMMU_MAX_CONTEXTS      65536
  18
  19 /* PMD_SHIFT determines the size of the area a second-level page table entry can map */
  20 #define SRMMU_REAL_PMD_SHIFT            18
  21 #define SRMMU_REAL_PMD_SIZE             (1UL << SRMMU_REAL_PMD_SHIFT)
  22 #define SRMMU_REAL_PMD_MASK             (~(SRMMU_REAL_PMD_SIZE-1))
  23 #define SRMMU_REAL_PMD_ALIGN(__addr)    (((__addr)+SRMMU_REAL_PMD_SIZE-1)&SRMMU_REAL_PMD_MASK)
  24
  25 /* PGDIR_SHIFT determines what a third-level page table entry can map */
  26 #define SRMMU_PGDIR_SHIFT       24
  27 #define SRMMU_PGDIR_SIZE        (1UL << SRMMU_PGDIR_SHIFT)
  28 #define SRMMU_PGDIR_MASK        (~(SRMMU_PGDIR_SIZE-1))
  29 #define SRMMU_PGDIR_ALIGN(addr) (((addr)+SRMMU_PGDIR_SIZE-1)&SRMMU_PGDIR_MASK)
  30
  31 #define SRMMU_REAL_PTRS_PER_PTE 64
  32 #define SRMMU_REAL_PTRS_PER_PMD 64
  33 #define SRMMU_PTRS_PER_PGD      256
  34
  35 #define SRMMU_REAL_PTE_TABLE_SIZE       (SRMMU_REAL_PTRS_PER_PTE*4)
  36 #define SRMMU_PMD_TABLE_SIZE            (SRMMU_REAL_PTRS_PER_PMD*4)
  37 #define SRMMU_PGD_TABLE_SIZE            (SRMMU_PTRS_PER_PGD*4)
  38
  39 /*
  40  * To support pagetables in highmem, Linux introduces APIs which
  41  * return struct page* and generally manipulate page tables when
  42  * they are not mapped into kernel space. Our hardware page tables
  43  * are smaller than pages. We lump hardware tabes into big, page sized
  44  * software tables.
  45  *
  46  * PMD_SHIFT determines the size of the area a second-level page table entry
  47  * can map, and our pmd_t is 16 times larger than normal.  The values which
  48  * were once defined here are now generic for 4c and srmmu, so they're
  49  * found in pgtable.h.
  50  */
  51 #define SRMMU_PTRS_PER_PMD      4
  52
  53 /* Definition of the values in the ET field of PTD's and PTE's */
  54 #define SRMMU_ET_MASK         0x3
  55 #define SRMMU_ET_INVALID      0x0
  56 #define SRMMU_ET_PTD          0x1
  57 #define SRMMU_ET_PTE          0x2
  58 #define SRMMU_ET_REPTE        0x3 /* AIEEE, SuperSparc II reverse endian page! */
  59
  60 /* Physical page extraction from PTP's and PTE's. */
  61 #define SRMMU_CTX_PMASK    0xfffffff0
  62 #define SRMMU_PTD_PMASK    0xfffffff0
  63 #define SRMMU_PTE_PMASK    0xffffff00
  64
  65 /* The pte non-page bits.  Some notes:
  66  * 1) cache, dirty, valid, and ref are frobbable
  67  *    for both supervisor and user pages.
  68  * 2) exec and write will only give the desired effect
  69  *    on user pages
  70  * 3) use priv and priv_readonly for changing the
  71  *    characteristics of supervisor ptes
  72  */
  73 #define SRMMU_CACHE        0x80
  74 #define SRMMU_DIRTY        0x40
  75 #define SRMMU_REF          0x20
  76 #define SRMMU_NOREAD       0x10
  77 #define SRMMU_EXEC         0x08
  78 #define SRMMU_WRITE        0x04
  79 #define SRMMU_VALID        0x02 /* SRMMU_ET_PTE */
  80 #define SRMMU_PRIV         0x1c
  81 #define SRMMU_PRIV_RDONLY  0x18
  82
  83 #define SRMMU_FILE         0x40 /* Implemented in software */
  84
  85 #define SRMMU_PTE_FILE_SHIFT     8      /* == 32-PTE_FILE_MAX_BITS */
  86
  87 #define SRMMU_CHG_MASK    (0xffffff00 | SRMMU_REF | SRMMU_DIRTY)
  88
  89 /* SRMMU swap entry encoding
  90  *
  91  * We use 5 bits for the type and 19 for the offset.  This gives us
  92  * 32 swapfiles of 4GB each.  Encoding looks like:
  93  *
  94  * oooooooooooooooooootttttRRRRRRRR
  95  * fedcba9876543210fedcba9876543210
  96  *
  97  * The bottom 8 bits are reserved for protection and status bits, especially
  98  * FILE and PRESENT.
  99  */
 100 #define SRMMU_SWP_TYPE_MASK     0x1f
 101 #define SRMMU_SWP_TYPE_SHIFT    SRMMU_PTE_FILE_SHIFT
 102 #define SRMMU_SWP_OFF_MASK      0x7ffff
 103 #define SRMMU_SWP_OFF_SHIFT     (SRMMU_PTE_FILE_SHIFT + 5)
 104
 105 /* Some day I will implement true fine grained access bits for
 106  * user pages because the SRMMU gives us the capabilities to
 107  * enforce all the protection levels that vma's can have.
 108  * XXX But for now...
 109  */
 110 #define SRMMU_PAGE_NONE    __pgprot(SRMMU_CACHE | \
 111                                     SRMMU_PRIV | SRMMU_REF)
 112 #define SRMMU_PAGE_SHARED  __pgprot(SRMMU_VALID | SRMMU_CACHE | \
 113                                     SRMMU_EXEC | SRMMU_WRITE | SRMMU_REF)
 114 #define SRMMU_PAGE_COPY    __pgprot(SRMMU_VALID | SRMMU_CACHE | \
 115                                     SRMMU_EXEC | SRMMU_REF)
 116 #define SRMMU_PAGE_RDONLY  __pgprot(SRMMU_VALID | SRMMU_CACHE | \
 117                                     SRMMU_EXEC | SRMMU_REF)
 118 #define SRMMU_PAGE_KERNEL  __pgprot(SRMMU_VALID | SRMMU_CACHE | SRMMU_PRIV | \
 119                                     SRMMU_DIRTY | SRMMU_REF)
 120
 121 /* SRMMU Register addresses in ASI 0x4.  These are valid for all
 122  * current SRMMU implementations that exist.
 123  */
 124 #define SRMMU_CTRL_REG           0x00000000
 125 #define SRMMU_CTXTBL_PTR         0x00000100
 126 #define SRMMU_CTX_REG            0x00000200
 127 #define SRMMU_FAULT_STATUS       0x00000300
 128 #define SRMMU_FAULT_ADDR         0x00000400
 129
 130 #define WINDOW_FLUSH(tmp1, tmp2)                                        \
 131         mov     0, tmp1;                                                \
 132 98:     ld      [%g6 + TI_UWINMASK], tmp2;                              \
 133         orcc    %g0, tmp2, %g0;                                         \
 134         add     tmp1, 1, tmp1;                                          \
 135         bne     98b;                                                    \
 136          save   %sp, -64, %sp;                                          \
 137 99:     subcc   tmp1, 1, tmp1;                                          \
 138         bne     99b;                                                    \
 139          restore %g0, %g0, %g0;
 140
 141 #ifndef __ASSEMBLY__
 142 extern unsigned long last_valid_pfn;
 143
 144 /* This makes sense. Honest it does - Anton */
 145 /* XXX Yes but it's ugly as sin.  FIXME. -KMW */
 146 extern void *srmmu_nocache_pool;
 147 #define __nocache_pa(VADDR) (((unsigned long)VADDR) - SRMMU_NOCACHE_VADDR + __pa((unsigned long)srmmu_nocache_pool))
 148 #define __nocache_va(PADDR) (__va((unsigned long)PADDR) - (unsigned long)srmmu_nocache_pool + SRMMU_NOCACHE_VADDR)
 149 #define __nocache_fix(VADDR) __va(__nocache_pa(VADDR))
 150
 151 /* Accessing the MMU control register. */
 152 unsigned int srmmu_get_mmureg(void);
 153 void srmmu_set_mmureg(unsigned long regval);
 154 void srmmu_set_ctable_ptr(unsigned long paddr);
 155 void srmmu_set_context(int context);
 156 int srmmu_get_context(void);
 157 unsigned int srmmu_get_fstatus(void);
 158 unsigned int srmmu_get_faddr(void);
 159
 160 /* This is guaranteed on all SRMMU's. */
 161 static inline void srmmu_flush_whole_tlb(void)
 162 {
 163         __asm__ __volatile__("sta %%g0, [%0] %1\n\t": :
 164                              "r" (0x400),        /* Flush entire TLB!! */
 165                              "i" (ASI_M_FLUSH_PROBE) : "memory");
 166
 167 }
 168
 169 static inline int
 170 srmmu_get_pte (unsigned long addr)
 171 {
 172         register unsigned long entry;
 173
 174         __asm__ __volatile__("\n\tlda [%1] %2,%0\n\t" :
 175                                 "=r" (entry):
 176                                 "r" ((addr & 0xfffff000) | 0x400), "i" (ASI_M_FLUSH_PROBE));
 177         return entry;
 178 }
 179
 180 #endif /* !(__ASSEMBLY__) */
 181
 182 #endif /* !(_SPARC_PGTSRMMU_H) */