arch/m68k/include/asm/pgtable_mm.h

   1 #ifndef _M68K_PGTABLE_H
   2 #define _M68K_PGTABLE_H
   3
   4 #include <asm-generic/4level-fixup.h>
   5
   6 #include <asm/setup.h>
   7
   8 #ifndef __ASSEMBLY__
   9 #include <asm/processor.h>
  10 #include <linux/sched.h>
  11 #include <linux/threads.h>
  12
  13 /*
  14  * This file contains the functions and defines necessary to modify and use
  15  * the m68k page table tree.
  16  */
  17
  18 #include <asm/virtconvert.h>
  19
  20 /* Certain architectures need to do special things when pte's
  21  * within a page table are directly modified.  Thus, the following
  22  * hook is made available.
  23  */
  24 #define set_pte(pteptr, pteval)                                 \
  25         do{                                                     \
  26                 *(pteptr) = (pteval);                           \
  27         } while(0)
  28 #define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
  29
  30
  31 /* PMD_SHIFT determines the size of the area a second-level page table can map */
  32 #ifdef CONFIG_SUN3
  33 #define PMD_SHIFT       17
  34 #else
  35 #define PMD_SHIFT       22
  36 #endif
  37 #define PMD_SIZE        (1UL << PMD_SHIFT)
  38 #define PMD_MASK        (~(PMD_SIZE-1))
  39
  40 /* PGDIR_SHIFT determines what a third-level page table entry can map */
  41 #ifdef CONFIG_SUN3
  42 #define PGDIR_SHIFT     17
  43 #else
  44 #define PGDIR_SHIFT     25
  45 #endif
  46 #define PGDIR_SIZE      (1UL << PGDIR_SHIFT)
  47 #define PGDIR_MASK      (~(PGDIR_SIZE-1))
  48
  49 /*
  50  * entries per page directory level: the m68k is configured as three-level,
  51  * so we do have PMD level physically.
  52  */
  53 #ifdef CONFIG_SUN3
  54 #define PTRS_PER_PTE   16
  55 #define PTRS_PER_PMD   1
  56 #define PTRS_PER_PGD   2048
  57 #else
  58 #define PTRS_PER_PTE    1024
  59 #define PTRS_PER_PMD    8
  60 #define PTRS_PER_PGD    128
  61 #endif
  62 #define USER_PTRS_PER_PGD       (TASK_SIZE/PGDIR_SIZE)
  63 #define FIRST_USER_ADDRESS      0
  64
  65 /* Virtual address region for use by kernel_map() */
  66 #ifdef CONFIG_SUN3
  67 #define KMAP_START     0x0DC00000
  68 #define KMAP_END       0x0E000000
  69 #else
  70 #define KMAP_START      0xd0000000
  71 #define KMAP_END        0xf0000000
  72 #endif
  73
  74 #ifndef CONFIG_SUN3
  75 /* Just any arbitrary offset to the start of the vmalloc VM area: the
  76  * current 8MB value just means that there will be a 8MB "hole" after the
  77  * physical memory until the kernel virtual memory starts.  That means that
  78  * any out-of-bounds memory accesses will hopefully be caught.
  79  * The vmalloc() routines leaves a hole of 4kB between each vmalloced
  80  * area for the same reason. ;)
  81  */
  82 #define VMALLOC_OFFSET  (8*1024*1024)
  83 #define VMALLOC_START (((unsigned long) high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
  84 #define VMALLOC_END KMAP_START
  85 #else
  86 extern unsigned long vmalloc_end;
  87 #define VMALLOC_START 0x0f800000
  88 #define VMALLOC_END vmalloc_end
  89 #endif /* CONFIG_SUN3 */
  90
  91 /* zero page used for uninitialized stuff */
  92 extern void *empty_zero_page;
  93
  94 /*
  95  * ZERO_PAGE is a global shared page that is always zero: used
  96  * for zero-mapped memory areas etc..
  97  */
  98 #define ZERO_PAGE(vaddr)        (virt_to_page(empty_zero_page))
  99
 100 /* number of bits that fit into a memory pointer */
 101 #define BITS_PER_PTR                    (8*sizeof(unsigned long))
 102
 103 /* to align the pointer to a pointer address */
 104 #define PTR_MASK                        (~(sizeof(void*)-1))
 105
 106 /* sizeof(void*)==1<<SIZEOF_PTR_LOG2 */
 107 /* 64-bit machines, beware!  SRB. */
 108 #define SIZEOF_PTR_LOG2                        2
 109
 110 extern void kernel_set_cachemode(void *addr, unsigned long size, int cmode);
 111
 112 /*
 113  * The m68k doesn't have any external MMU info: the kernel page
 114  * tables contain all the necessary information.  The Sun3 does, but
 115  * they are updated on demand.
 116  */
 117 static inline void update_mmu_cache(struct vm_area_struct *vma,
 118                                     unsigned long address, pte_t pte)
 119 {
 120 }
 121
 122 #endif /* !__ASSEMBLY__ */
 123
 124 #define kern_addr_valid(addr)   (1)
 125
 126 #define io_remap_pfn_range(vma, vaddr, pfn, size, prot)         \
 127                 remap_pfn_range(vma, vaddr, pfn, size, prot)
 128
 129 /* MMU-specific headers */
 130
 131 #ifdef CONFIG_SUN3
 132 #include <asm/sun3_pgtable.h>
 133 #else
 134 #include <asm/motorola_pgtable.h>
 135 #endif
 136
 137 #ifndef __ASSEMBLY__
 138 /*
 139  * Macro to mark a page protection value as "uncacheable".
 140  */
 141 #ifdef SUN3_PAGE_NOCACHE
 142 # define __SUN3_PAGE_NOCACHE    SUN3_PAGE_NOCACHE
 143 #else
 144 # define __SUN3_PAGE_NOCACHE    0
 145 #endif
 146 #define pgprot_noncached(prot)                                                  \
 147         (MMU_IS_SUN3                                                            \
 148          ? (__pgprot(pgprot_val(prot) | __SUN3_PAGE_NOCACHE))                   \
 149          : ((MMU_IS_851 || MMU_IS_030)                                          \
 150             ? (__pgprot(pgprot_val(prot) | _PAGE_NOCACHE030))                   \
 151             : (MMU_IS_040 || MMU_IS_060)                                        \
 152             ? (__pgprot((pgprot_val(prot) & _CACHEMASK040) | _PAGE_NOCACHE_S))  \
 153             : (prot)))
 154
 155 #include <asm-generic/pgtable.h>
 156 #endif /* !__ASSEMBLY__ */
 157
 158 /*
 159  * No page table caches to initialise
 160  */
 161 #define pgtable_cache_init()    do { } while (0)
 162
 163 #define check_pgt_cache()       do { } while (0)
 164
 165 #endif /* _M68K_PGTABLE_H */