arch/mips/include/asm/paccess.h

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1996, 1997, 1998, 1999, 2000 by Ralf Baechle
   7  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
   8  *
   9  * Protected memory access.  Used for everything that might take revenge
  10  * by sending a DBE error like accessing possibly non-existant memory or
  11  * devices.
  12  */
  13 #ifndef _ASM_PACCESS_H
  14 #define _ASM_PACCESS_H
  15
  16 #include <linux/errno.h>
  17
  18 #ifdef CONFIG_32BIT
  19 #define __PA_ADDR       ".word"
  20 #endif
  21 #ifdef CONFIG_64BIT
  22 #define __PA_ADDR       ".dword"
  23 #endif
  24
  25 extern asmlinkage void handle_ibe(void);
  26 extern asmlinkage void handle_dbe(void);
  27
  28 #define put_dbe(x, ptr) __put_dbe((x), (ptr), sizeof(*(ptr)))
  29 #define get_dbe(x, ptr) __get_dbe((x), (ptr), sizeof(*(ptr)))
  30
  31 struct __large_pstruct { unsigned long buf[100]; };
  32 #define __mp(x) (*(struct __large_pstruct *)(x))
  33
  34 #define __get_dbe(x, ptr, size)                                         \
  35 ({                                                                      \
  36         long __gu_err;                                                  \
  37         __typeof__(*(ptr)) __gu_val;                                    \
  38         unsigned long __gu_addr;                                        \
  39         __asm__("":"=r" (__gu_val));                                    \
  40         __gu_addr = (unsigned long) (ptr);                              \
  41         __asm__("":"=r" (__gu_err));                                    \
  42         switch (size) {                                                 \
  43         case 1: __get_dbe_asm("lb"); break;                             \
  44         case 2: __get_dbe_asm("lh"); break;                             \
  45         case 4: __get_dbe_asm("lw"); break;                             \
  46         case 8:  __get_dbe_asm("ld"); break;                            \
  47         default: __get_dbe_unknown(); break;                            \
  48         }                                                               \
  49         x = (__typeof__(*(ptr))) __gu_val;                              \
  50         __gu_err;                                                       \
  51 })
  52
  53 #define __get_dbe_asm(insn)                                             \
  54 {                                                                       \
  55         __asm__ __volatile__(                                           \
  56         "1:\t" insn "\t%1,%2\n\t"                                       \
  57         "move\t%0,$0\n"                                                 \
  58         "2:\n\t"                                                        \
  59         ".section\t.fixup,\"ax\"\n"                                     \
  60         "3:\tli\t%0,%3\n\t"                                             \
  61         "move\t%1,$0\n\t"                                               \
  62         "j\t2b\n\t"                                                     \
  63         ".previous\n\t"                                                 \
  64         ".section\t__dbe_table,\"a\"\n\t"                               \
  65         __PA_ADDR "\t1b, 3b\n\t"                                        \
  66         ".previous"                                                     \
  67         :"=r" (__gu_err), "=r" (__gu_val)                               \
  68         :"o" (__mp(__gu_addr)), "i" (-EFAULT));                         \
  69 }
  70
  71 extern void __get_dbe_unknown(void);
  72
  73 #define __put_dbe(x, ptr, size)                                         \
  74 ({                                                                      \
  75         long __pu_err;                                                  \
  76         __typeof__(*(ptr)) __pu_val;                                    \
  77         long __pu_addr;                                                 \
  78         __pu_val = (x);                                                 \
  79         __pu_addr = (long) (ptr);                                       \
  80         __asm__("":"=r" (__pu_err));                                    \
  81         switch (size) {                                                 \
  82         case 1: __put_dbe_asm("sb"); break;                             \
  83         case 2: __put_dbe_asm("sh"); break;                             \
  84         case 4: __put_dbe_asm("sw"); break;                             \
  85         case 8: __put_dbe_asm("sd"); break;                             \
  86         default: __put_dbe_unknown(); break;                            \
  87         }                                                               \
  88         __pu_err;                                                       \
  89 })
  90
  91 #define __put_dbe_asm(insn)                                             \
  92 {                                                                       \
  93         __asm__ __volatile__(                                           \
  94         "1:\t" insn "\t%1,%2\n\t"                                       \
  95         "move\t%0,$0\n"                                                 \
  96         "2:\n\t"                                                        \
  97         ".section\t.fixup,\"ax\"\n"                                     \
  98         "3:\tli\t%0,%3\n\t"                                             \
  99         "j\t2b\n\t"                                                     \
 100         ".previous\n\t"                                                 \
 101         ".section\t__dbe_table,\"a\"\n\t"                               \
 102         __PA_ADDR "\t1b, 3b\n\t"                                        \
 103         ".previous"                                                     \
 104         : "=r" (__pu_err)                                               \
 105         : "r" (__pu_val), "o" (__mp(__pu_addr)), "i" (-EFAULT));        \
 106 }
 107
 108 extern void __put_dbe_unknown(void);
 109
 110 extern unsigned long search_dbe_table(unsigned long addr);
 111
 112 #endif /* _ASM_PACCESS_H */