include/asm-mips/interrupt.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) 1994, 95, 96, 97, 98, 99, 2003 by Ralf Baechle
   7  * Copyright (C) 1996 by Paul M. Antoine
   8  * Copyright (C) 1999 Silicon Graphics
   9  * Copyright (C) 2000 MIPS Technologies, Inc.
  10  */
  11 #ifndef _ASM_INTERRUPT_H
  12 #define _ASM_INTERRUPT_H
  13
  14 #include <linux/config.h>
  15 #include <asm/hazards.h>
  16
  17 __asm__ (
  18         "       .macro  local_irq_enable                                \n"
  19         "       .set    push                                            \n"
  20         "       .set    reorder                                         \n"
  21         "       .set    noat                                            \n"
  22 #ifdef CONFIG_CPU_MIPSR2
  23         "       .set    mips32r2                                        \n"
  24         "       ei                                                      \n"
  25         "       .set    mips0                                           \n"
  26 #else
  27         "       mfc0    $1,$12                                          \n"
  28         "       ori     $1,0x1f                                         \n"
  29         "       xori    $1,0x1e                                         \n"
  30         "       mtc0    $1,$12                                          \n"
  31 #endif
  32         "       irq_enable_hazard                                       \n"
  33         "       .set    pop                                             \n"
  34         "       .endm");
  35
  36 static inline void local_irq_enable(void)
  37 {
  38         __asm__ __volatile__(
  39                 "local_irq_enable"
  40                 : /* no outputs */
  41                 : /* no inputs */
  42                 : "memory");
  43 }
  44
  45 /*
  46  * For cli() we have to insert nops to make sure that the new value
  47  * has actually arrived in the status register before the end of this
  48  * macro.
  49  * R4000/R4400 need three nops, the R4600 two nops and the R10000 needs
  50  * no nops at all.
  51  */
  52 /*
  53  * For TX49, operating only IE bit is not enough.
  54  *
  55  * If mfc0 $12 follows store and the mfc0 is last instruction of a
  56  * page and fetching the next instruction causes TLB miss, the result
  57  * of the mfc0 might wrongly contain EXL bit.
  58  *
  59  * ERT-TX49H2-027, ERT-TX49H3-012, ERT-TX49HL3-006, ERT-TX49H4-008
  60  *
  61  * Workaround: mask EXL bit of the result or place a nop before mfc0.
  62  */
  63 __asm__ (
  64         "       .macro  local_irq_disable\n"
  65         "       .set    push                                            \n"
  66         "       .set    noat                                            \n"
  67 #ifdef CONFIG_CPU_MIPSR2
  68         "       .set    mips32r2                                        \n"
  69         "       di                                                      \n"
  70         "       .set    mips0                                           \n"
  71 #else
  72         "       mfc0    $1,$12                                          \n"
  73         "       ori     $1,0x1f                                         \n"
  74         "       xori    $1,0x1f                                         \n"
  75         "       .set    noreorder                                       \n"
  76         "       mtc0    $1,$12                                          \n"
  77 #endif
  78         "       irq_disable_hazard                                      \n"
  79         "       .set    pop                                             \n"
  80         "       .endm                                                   \n");
  81
  82 static inline void local_irq_disable(void)
  83 {
  84         __asm__ __volatile__(
  85                 "local_irq_disable"
  86                 : /* no outputs */
  87                 : /* no inputs */
  88                 : "memory");
  89 }
  90
  91 __asm__ (
  92         "       .macro  local_save_flags flags                          \n"
  93         "       .set    push                                            \n"
  94         "       .set    reorder                                         \n"
  95         "       mfc0    \\flags, $12                                    \n"
  96         "       .set    pop                                             \n"
  97         "       .endm                                                   \n");
  98
  99 #define local_save_flags(x)                                             \
 100 __asm__ __volatile__(                                                   \
 101         "local_save_flags %0"                                           \
 102         : "=r" (x))
 103
 104 __asm__ (
 105         "       .macro  local_irq_save result                           \n"
 106         "       .set    push                                            \n"
 107         "       .set    reorder                                         \n"
 108         "       .set    noat                                            \n"
 109 #ifdef CONFIG_CPU_MIPSR2
 110         "       .set    mips32r2                                        \n"
 111         "       di      \\result                                        \n"
 112         "       andi    \\result, 1                                     \n"
 113         "       .set    mips0                                           \n"
 114 #else
 115         "       mfc0    \\result, $12                                   \n"
 116         "       ori     $1, \\result, 0x1f                              \n"
 117         "       xori    $1, 0x1f                                        \n"
 118         "       .set    noreorder                                       \n"
 119         "       mtc0    $1, $12                                         \n"
 120 #endif
 121         "       irq_disable_hazard                                      \n"
 122         "       .set    pop                                             \n"
 123         "       .endm                                                   \n");
 124
 125 #define local_irq_save(x)                                               \
 126 __asm__ __volatile__(                                                   \
 127         "local_irq_save\t%0"                                            \
 128         : "=r" (x)                                                      \
 129         : /* no inputs */                                               \
 130         : "memory")
 131
 132 __asm__ (
 133         "       .macro  local_irq_restore flags                         \n"
 134         "       .set    push                                            \n"
 135         "       .set    noreorder                                       \n"
 136         "       .set    noat                                            \n"
 137 #if defined(CONFIG_CPU_MIPSR2) && defined(CONFIG_IRQ_CPU)
 138         /*
 139          * Slow, but doesn't suffer from a relativly unlikely race
 140          * condition we're having since days 1.
 141          */
 142         "       .set    mips32r2                                        \n"
 143         "       beqz    \\flags, 1f                                     \n"
 144         "        di                                                     \n"
 145         "       ei                                                      \n"
 146         "       .set    mips0                                           \n"
 147         "1:                                                             \n"
 148 #elif defined(CONFIG_CPU_MIPSR2)
 149         /*
 150          * Fast, dangerous.  Life is fun, life is good.
 151          */
 152         "       mfc0    $1, $12                                         \n"
 153         "       ins     $1, \\flags, 0, 1                               \n"
 154         "       mtc0    $1, $12                                         \n"
 155 #else
 156         "       mfc0    $1, $12                                         \n"
 157         "       andi    \\flags, 1                                      \n"
 158         "       ori     $1, 0x1f                                        \n"
 159         "       xori    $1, 0x1f                                        \n"
 160         "       or      \\flags, $1                                     \n"
 161         "       mtc0    \\flags, $12                                    \n"
 162 #endif
 163         "       irq_disable_hazard                                      \n"
 164         "       .set    pop                                             \n"
 165         "       .endm                                                   \n");
 166
 167 #define local_irq_restore(flags)                                        \
 168 do {                                                                    \
 169         unsigned long __tmp1;                                           \
 170                                                                         \
 171         __asm__ __volatile__(                                           \
 172                 "local_irq_restore\t%0"                                 \
 173                 : "=r" (__tmp1)                                         \
 174                 : "0" (flags)                                           \
 175                 : "memory");                                            \
 176 } while(0)
 177
 178 #define irqs_disabled()                                                 \
 179 ({                                                                      \
 180         unsigned long flags;                                            \
 181         local_save_flags(flags);                                        \
 182         !(flags & 1);                                                   \
 183 })
 184
 185 #endif /* _ASM_INTERRUPT_H */