arch/m68k/mm/cache.c

   1 /*
   2  *  linux/arch/m68k/mm/cache.c
   3  *
   4  *  Instruction cache handling
   5  *
   6  *  Copyright (C) 1995  Hamish Macdonald
   7  */
   8
   9 #include <linux/module.h>
  10 #include <asm/pgalloc.h>
  11 #include <asm/traps.h>
  12
  13
  14 static unsigned long virt_to_phys_slow(unsigned long vaddr)
  15 {
  16         if (CPU_IS_060) {
  17                 unsigned long paddr;
  18
  19                 /* The PLPAR instruction causes an access error if the translation
  20                  * is not possible. To catch this we use the same exception mechanism
  21                  * as for user space accesses in <asm/uaccess.h>. */
  22                 asm volatile (".chip 68060\n"
  23                               "1: plpar (%0)\n"
  24                               ".chip 68k\n"
  25                               "2:\n"
  26                               ".section .fixup,\"ax\"\n"
  27                               "   .even\n"
  28                               "3: sub.l %0,%0\n"
  29                               "   jra 2b\n"
  30                               ".previous\n"
  31                               ".section __ex_table,\"a\"\n"
  32                               "   .align 4\n"
  33                               "   .long 1b,3b\n"
  34                               ".previous"
  35                               : "=a" (paddr)
  36                               : "0" (vaddr));
  37                 return paddr;
  38         } else if (CPU_IS_040) {
  39                 unsigned long mmusr;
  40
  41                 asm volatile (".chip 68040\n\t"
  42                               "ptestr (%1)\n\t"
  43                               "movec %%mmusr, %0\n\t"
  44                               ".chip 68k"
  45                               : "=r" (mmusr)
  46                               : "a" (vaddr));
  47
  48                 if (mmusr & MMU_R_040)
  49                         return (mmusr & PAGE_MASK) | (vaddr & ~PAGE_MASK);
  50         } else {
  51                 unsigned short mmusr;
  52                 unsigned long *descaddr;
  53
  54                 asm volatile ("ptestr %3,%2@,#7,%0\n\t"
  55                               "pmove %%psr,%1@"
  56                               : "=a&" (descaddr)
  57                               : "a" (&mmusr), "a" (vaddr), "d" (get_fs().seg));
  58                 if (mmusr & (MMU_I|MMU_B|MMU_L))
  59                         return 0;
  60                 descaddr = phys_to_virt((unsigned long)descaddr);
  61                 switch (mmusr & MMU_NUM) {
  62                 case 1:
  63                         return (*descaddr & 0xfe000000) | (vaddr & 0x01ffffff);
  64                 case 2:
  65                         return (*descaddr & 0xfffc0000) | (vaddr & 0x0003ffff);
  66                 case 3:
  67                         return (*descaddr & PAGE_MASK) | (vaddr & ~PAGE_MASK);
  68                 }
  69         }
  70         return 0;
  71 }
  72
  73 /* Push n pages at kernel virtual address and clear the icache */
  74 /* RZ: use cpush %bc instead of cpush %dc, cinv %ic */
  75 void flush_icache_range(unsigned long address, unsigned long endaddr)
  76 {
  77
  78         if (CPU_IS_040_OR_060) {
  79                 address &= PAGE_MASK;
  80
  81                 do {
  82                         asm volatile ("nop\n\t"
  83                                       ".chip 68040\n\t"
  84                                       "cpushp %%bc,(%0)\n\t"
  85                                       ".chip 68k"
  86                                       : : "a" (virt_to_phys_slow(address)));
  87                         address += PAGE_SIZE;
  88                 } while (address < endaddr);
  89         } else {
  90                 unsigned long tmp;
  91                 asm volatile ("movec %%cacr,%0\n\t"
  92                               "orw %1,%0\n\t"
  93                               "movec %0,%%cacr"
  94                               : "=&d" (tmp)
  95                               : "di" (FLUSH_I));
  96         }
  97 }
  98 EXPORT_SYMBOL(flush_icache_range);
  99
 100 void flush_icache_user_range(struct vm_area_struct *vma, struct page *page,
 101                              unsigned long addr, int len)
 102 {
 103         if (CPU_IS_040_OR_060) {
 104                 asm volatile ("nop\n\t"
 105                               ".chip 68040\n\t"
 106                               "cpushp %%bc,(%0)\n\t"
 107                               ".chip 68k"
 108                               : : "a" (page_to_phys(page)));
 109         } else {
 110                 unsigned long tmp;
 111                 asm volatile ("movec %%cacr,%0\n\t"
 112                               "orw %1,%0\n\t"
 113                               "movec %0,%%cacr"
 114                               : "=&d" (tmp)
 115                               : "di" (FLUSH_I));
 116         }
 117 }
 118