include/asm-mips/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/config.h>
  17 #include <linux/errno.h>
  18
  19 #ifdef CONFIG_MIPS32
  20 #define __PA_ADDR       ".word"
  21 #endif
  22 #ifdef CONFIG_MIPS64
  23 #define __PA_ADDR       ".dword"
  24 #endif
  25
  26 extern asmlinkage void handle_ibe(void);
  27 extern asmlinkage void handle_dbe(void);
  28
  29 #define put_dbe(x,ptr) __put_dbe((x),(ptr),sizeof(*(ptr)))
  30 #define get_dbe(x,ptr) __get_dbe((x),(ptr),sizeof(*(ptr)))
  31
  32 struct __large_pstruct { unsigned long buf[100]; };
  33 #define __mp(x) (*(struct __large_pstruct *)(x))
  34
  35 #define __get_dbe(x,ptr,size)                                           \
  36 ({                                                                      \
  37         long __gu_err;                                                  \
  38         __typeof(*(ptr)) __gu_val;                                      \
  39         unsigned long __gu_addr;                                        \
  40         __asm__("":"=r" (__gu_val));                                    \
  41         __gu_addr = (unsigned long) (ptr);                              \
  42         __asm__("":"=r" (__gu_err));                                    \
  43         switch (size) {                                                 \
  44         case 1: __get_dbe_asm("lb"); break;                             \
  45         case 2: __get_dbe_asm("lh"); break;                             \
  46         case 4: __get_dbe_asm("lw"); break;                             \
  47         case 8:  __get_dbe_asm("ld"); break;                            \
  48         default: __get_dbe_unknown(); break;                            \
  49         }                                                               \
  50         x = (__typeof__(*(ptr))) __gu_val;                              \
  51         __gu_err;                                                       \
  52 })
  53
  54 #define __get_dbe_asm(insn)                                             \
  55 ({                                                                      \
  56         __asm__ __volatile__(                                           \
  57         "1:\t" insn "\t%1,%2\n\t"                                       \
  58         "move\t%0,$0\n"                                                 \
  59         "2:\n\t"                                                        \
  60         ".section\t.fixup,\"ax\"\n"                                     \
  61         "3:\tli\t%0,%3\n\t"                                             \
  62         "move\t%1,$0\n\t"                                               \
  63         "j\t2b\n\t"                                                     \
  64         ".previous\n\t"                                                 \
  65         ".section\t__dbe_table,\"a\"\n\t"                               \
  66         __PA_ADDR "\t1b, 3b\n\t"                                        \
  67         ".previous"                                                     \
  68         :"=r" (__gu_err), "=r" (__gu_val)                               \
  69         :"o" (__mp(__gu_addr)), "i" (-EFAULT));                         \
  70 })
  71
  72 extern void __get_dbe_unknown(void);
  73
  74 #define __put_dbe(x,ptr,size)                                           \
  75 ({                                                                      \
  76         long __pu_err;                                                  \
  77         __typeof__(*(ptr)) __pu_val;                                    \
  78         long __pu_addr;                                                 \
  79         __pu_val = (x);                                                 \
  80         __pu_addr = (long) (ptr);                                       \
  81         __asm__("":"=r" (__pu_err));                                    \
  82         switch (size) {                                                 \
  83         case 1: __put_dbe_asm("sb"); break;                             \
  84         case 2: __put_dbe_asm("sh"); break;                             \
  85         case 4: __put_dbe_asm("sw"); break;                             \
  86         case 8: __put_dbe_asm("sd"); break;                             \
  87         default: __put_dbe_unknown(); break;                            \
  88         }                                                               \
  89         __pu_err;                                                       \
  90 })
  91
  92 #define __put_dbe_asm(insn)                                             \
  93 ({                                                                      \
  94         __asm__ __volatile__(                                           \
  95         "1:\t" insn "\t%1,%2\n\t"                                       \
  96         "move\t%0,$0\n"                                                 \
  97         "2:\n\t"                                                        \
  98         ".section\t.fixup,\"ax\"\n"                                     \
  99         "3:\tli\t%0,%3\n\t"                                             \
 100         "j\t2b\n\t"                                                     \
 101         ".previous\n\t"                                                 \
 102         ".section\t__dbe_table,\"a\"\n\t"                               \
 103         __PA_ADDR "\t1b, 3b\n\t"                                        \
 104         ".previous"                                                     \
 105         : "=r" (__pu_err)                                               \
 106         : "r" (__pu_val), "o" (__mp(__pu_addr)), "i" (-EFAULT));        \
 107 })
 108
 109 extern void __put_dbe_unknown(void);
 110
 111 extern unsigned long search_dbe_table(unsigned long addr);
 112
 113 #endif /* _ASM_PACCESS_H */