include/asm-m68k/pgtable.h

   1 #ifndef _M68K_PGTABLE_H
   2 #define _M68K_PGTABLE_H
   3
   4 #include <asm-generic/4level-fixup.h>
   5
   6 #include <linux/config.h>
   7 #include <asm/setup.h>
   8
   9 #ifndef __ASSEMBLY__
  10 #include <asm/processor.h>
  11 #include <linux/sched.h>
  12 #include <linux/threads.h>
  13
  14 /*
  15  * This file contains the functions and defines necessary to modify and use
  16  * the m68k page table tree.
  17  */
  18
  19 #include <asm/virtconvert.h>
  20
  21 /* Certain architectures need to do special things when pte's
  22  * within a page table are directly modified.  Thus, the following
  23  * hook is made available.
  24  */
  25 #define set_pte(pteptr, pteval)                                 \
  26         do{                                                     \
  27                 *(pteptr) = (pteval);                           \
  28         } while(0)
  29 #define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
  30
  31
  32 /* PMD_SHIFT determines the size of the area a second-level page table can map */
  33 #ifdef CONFIG_SUN3
  34 #define PMD_SHIFT       17
  35 #else
  36 #define PMD_SHIFT       22
  37 #endif
  38 #define PMD_SIZE        (1UL << PMD_SHIFT)
  39 #define PMD_MASK        (~(PMD_SIZE-1))
  40
  41 /* PGDIR_SHIFT determines what a third-level page table entry can map */
  42 #ifdef CONFIG_SUN3
  43 #define PGDIR_SHIFT     17
  44 #else
  45 #define PGDIR_SHIFT     25
  46 #endif
  47 #define PGDIR_SIZE      (1UL << PGDIR_SHIFT)
  48 #define PGDIR_MASK      (~(PGDIR_SIZE-1))
  49
  50 /*
  51  * entries per page directory level: the m68k is configured as three-level,
  52  * so we do have PMD level physically.
  53  */
  54 #ifdef CONFIG_SUN3
  55 #define PTRS_PER_PTE   16
  56 #define PTRS_PER_PMD   1
  57 #define PTRS_PER_PGD   2048
  58 #else
  59 #define PTRS_PER_PTE    1024
  60 #define PTRS_PER_PMD    8
  61 #define PTRS_PER_PGD    128
  62 #endif
  63 #define USER_PTRS_PER_PGD       (TASK_SIZE/PGDIR_SIZE)
  64 #define FIRST_USER_ADDRESS      0
  65
  66 /* Virtual address region for use by kernel_map() */
  67 #ifdef CONFIG_SUN3
  68 #define KMAP_START     0x0DC00000
  69 #define KMAP_END       0x0E000000
  70 #else
  71 #define KMAP_START      0xd0000000
  72 #define KMAP_END        0xf0000000
  73 #endif
  74
  75 #ifndef CONFIG_SUN3
  76 /* Just any arbitrary offset to the start of the vmalloc VM area: the
  77  * current 8MB value just means that there will be a 8MB "hole" after the
  78  * physical memory until the kernel virtual memory starts.  That means that
  79  * any out-of-bounds memory accesses will hopefully be caught.
  80  * The vmalloc() routines leaves a hole of 4kB between each vmalloced
  81  * area for the same reason. ;)
  82  */
  83 #define VMALLOC_OFFSET  (8*1024*1024)
  84 #define VMALLOC_START (((unsigned long) high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
  85 #define VMALLOC_END KMAP_START
  86 #else
  87 extern unsigned long vmalloc_end;
  88 #define VMALLOC_START 0x0f800000
  89 #define VMALLOC_END vmalloc_end
  90 #endif /* CONFIG_SUN3 */
  91
  92 /* zero page used for uninitialized stuff */
  93 extern void *empty_zero_page;
  94
  95 /*
  96  * ZERO_PAGE is a global shared page that is always zero: used
  97  * for zero-mapped memory areas etc..
  98  */
  99 #define ZERO_PAGE(vaddr)        (virt_to_page(empty_zero_page))
 100
 101 /* number of bits that fit into a memory pointer */
 102 #define BITS_PER_PTR                    (8*sizeof(unsigned long))
 103
 104 /* to align the pointer to a pointer address */
 105 #define PTR_MASK                        (~(sizeof(void*)-1))
 106
 107 /* sizeof(void*)==1<<SIZEOF_PTR_LOG2 */
 108 /* 64-bit machines, beware!  SRB. */
 109 #define SIZEOF_PTR_LOG2                        2
 110
 111 /*
 112  * Check if the addr/len goes up to the end of a physical
 113  * memory chunk.  Used for DMA functions.
 114  */
 115 #ifdef CONFIG_SINGLE_MEMORY_CHUNK
 116 /*
 117  * It makes no sense to consider whether we cross a memory boundary if
 118  * we support just one physical chunk of memory.
 119  */
 120 static inline int mm_end_of_chunk(unsigned long addr, int len)
 121 {
 122         return 0;
 123 }
 124 #else
 125 int mm_end_of_chunk (unsigned long addr, int len);
 126 #endif
 127
 128 extern void kernel_set_cachemode(void *addr, unsigned long size, int cmode);
 129
 130 /*
 131  * The m68k doesn't have any external MMU info: the kernel page
 132  * tables contain all the necessary information.  The Sun3 does, but
 133  * they are updated on demand.
 134  */
 135 static inline void update_mmu_cache(struct vm_area_struct *vma,
 136                                     unsigned long address, pte_t pte)
 137 {
 138 }
 139
 140 #endif /* !__ASSEMBLY__ */
 141
 142 #define kern_addr_valid(addr)   (1)
 143
 144 #define io_remap_pfn_range(vma, vaddr, pfn, size, prot)         \
 145                 remap_pfn_range(vma, vaddr, pfn, size, prot)
 146
 147 #define MK_IOSPACE_PFN(space, pfn)      (pfn)
 148 #define GET_IOSPACE(pfn)                0
 149 #define GET_PFN(pfn)                    (pfn)
 150
 151 /* MMU-specific headers */
 152
 153 #ifdef CONFIG_SUN3
 154 #include <asm/sun3_pgtable.h>
 155 #else
 156 #include <asm/motorola_pgtable.h>
 157 #endif
 158
 159 #ifndef __ASSEMBLY__
 160 #include <asm-generic/pgtable.h>
 161
 162 /*
 163  * Macro to mark a page protection value as "uncacheable".
 164  */
 165 #ifdef SUN3_PAGE_NOCACHE
 166 # define __SUN3_PAGE_NOCACHE    SUN3_PAGE_NOCACHE
 167 #else
 168 # define __SUN3_PAGE_NOCACHE    0
 169 #endif
 170 #define pgprot_noncached(prot)                                                  \
 171         (MMU_IS_SUN3                                                            \
 172          ? (__pgprot(pgprot_val(prot) | __SUN3_PAGE_NOCACHE))                   \
 173          : ((MMU_IS_851 || MMU_IS_030)                                          \
 174             ? (__pgprot(pgprot_val(prot) | _PAGE_NOCACHE030))                   \
 175             : (MMU_IS_040 || MMU_IS_060)                                        \
 176             ? (__pgprot((pgprot_val(prot) & _CACHEMASK040) | _PAGE_NOCACHE_S))  \
 177             : (prot)))
 178
 179 #endif /* !__ASSEMBLY__ */
 180
 181 /*
 182  * No page table caches to initialise
 183  */
 184 #define pgtable_cache_init()    do { } while (0)
 185
 186 #define check_pgt_cache()       do { } while (0)
 187
 188 #endif /* _M68K_PGTABLE_H */