LXR linux/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;                                                \
 13298:     ld      [%g6 + TI_UWINMASK], tmp2;                              \
 133        orcc    %g0, tmp2, %g0;                                         \
 134        add     tmp1, 1, tmp1;                                          \
 135        bne     98b;                                                    \
 136         save   %sp, -64, %sp;                                          \
 13799:     subcc   tmp1, 1, tmp1;                                          \
 138        bne     99b;                                                    \
 139         restore %g0, %g0, %g0;
 140
 141#ifndef __ASSEMBLY__
 142extern 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 */
 146extern 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. */
 152unsigned int srmmu_get_mmureg(void);
 153void srmmu_set_mmureg(unsigned long regval);
 154void srmmu_set_ctable_ptr(unsigned long paddr);
 155void srmmu_set_context(int context);
 156int srmmu_get_context(void);
 157unsigned int srmmu_get_fstatus(void);
 158unsigned int srmmu_get_faddr(void);
 159
 160/* This is guaranteed on all SRMMU's. */
 161static 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
 169static inline int
 170srmmu_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) */
 183