include/asm-mips64/system.h

   1 /* $Id: system.h,v 1.5 2000/01/27 07:48:08 kanoj Exp $
   2  *
   3  * This file is subject to the terms and conditions of the GNU General Public
   4  * License.  See the file "COPYING" in the main directory of this archive
   5  * for more details.
   6  *
   7  * Copyright (C) 1994, 1995, 1996, 1997, 1998, 1999 by Ralf Baechle
   8  * Modified further for R[236]000 by Paul M. Antoine, 1996
   9  * Copyright (C) 1999 Silicon Graphics
  10  */
  11 #ifndef _ASM_SYSTEM_H
  12 #define _ASM_SYSTEM_H
  13
  14 #include <linux/config.h>
  15
  16 #include <asm/sgidefs.h>
  17 #include <linux/kernel.h>
  18
  19 extern __inline__ void
  20 __sti(void)
  21 {
  22         __asm__ __volatile__(
  23                 ".set\tnoreorder\n\t"
  24                 ".set\tnoat\n\t"
  25                 "mfc0\t$1,$12\n\t"
  26                 "ori\t$1,0x1f\n\t"
  27                 "xori\t$1,0x1e\n\t"
  28                 "mtc0\t$1,$12\n\t"
  29                 ".set\tat\n\t"
  30                 ".set\treorder"
  31                 : /* no outputs */
  32                 : /* no inputs */
  33                 : "$1", "memory");
  34 }
  35
  36 /*
  37  * For cli() we have to insert nops to make shure that the new value
  38  * has actually arrived in the status register before the end of this
  39  * macro.
  40  * R4000/R4400 need three nops, the R4600 two nops and the R10000 needs
  41  * no nops at all.
  42  */
  43 extern __inline__ void
  44 __cli(void)
  45 {
  46         __asm__ __volatile__(
  47                 ".set\tnoreorder\n\t"
  48                 ".set\tnoat\n\t"
  49                 "mfc0\t$1,$12\n\t"
  50                 "ori\t$1,1\n\t"
  51                 "xori\t$1,1\n\t"
  52                 "mtc0\t$1,$12\n\t"
  53                 "nop\n\t"
  54                 "nop\n\t"
  55                 "nop\n\t"
  56                 ".set\tat\n\t"
  57                 ".set\treorder"
  58                 : /* no outputs */
  59                 : /* no inputs */
  60                 : "$1", "memory");
  61 }
  62
  63 #define __save_flags(x)                  \
  64 __asm__ __volatile__(                    \
  65         ".set\tnoreorder\n\t"            \
  66         "mfc0\t%0,$12\n\t"               \
  67         ".set\treorder"                  \
  68         : "=r" (x)                       \
  69         : /* no inputs */                \
  70         : "memory")
  71
  72 #define __save_and_cli(x)                \
  73 __asm__ __volatile__(                    \
  74         ".set\tnoreorder\n\t"            \
  75         ".set\tnoat\n\t"                 \
  76         "mfc0\t%0,$12\n\t"               \
  77         "ori\t$1,%0,1\n\t"               \
  78         "xori\t$1,1\n\t"                 \
  79         "mtc0\t$1,$12\n\t"               \
  80         "nop\n\t"                        \
  81         "nop\n\t"                        \
  82         "nop\n\t"                        \
  83         ".set\tat\n\t"                   \
  84         ".set\treorder"                  \
  85         : "=r" (x)                       \
  86         : /* no inputs */                \
  87         : "$1", "memory")
  88
  89 extern void __inline__
  90 __restore_flags(int flags)
  91 {
  92         __asm__ __volatile__(
  93                 ".set\tnoreorder\n\t"
  94                 "mfc0\t$8,$12\n\t"
  95                 "li\t$9,0xff00\n\t"
  96                 "and\t$8,$9\n\t"
  97                 "nor\t$9,$0,$9\n\t"
  98                 "and\t%0,$9\n\t"
  99                 "or\t%0,$8\n\t"
 100                 "mtc0\t%0,$12\n\t"
 101                 "nop\n\t"
 102                 "nop\n\t"
 103                 "nop\n\t"
 104                 ".set\treorder"
 105                 : /* no output */
 106                 : "r" (flags)
 107                 : "$8", "$9", "memory");
 108 }
 109
 110 #ifdef CONFIG_SMP
 111
 112 extern void __global_cli(void);
 113 extern void __global_sti(void);
 114 extern unsigned long __global_save_flags(void);
 115 extern void __global_restore_flags(unsigned long);
 116 #define cli() __global_cli()
 117 #define sti() __global_sti()
 118 #define save_flags(x) ((x)=__global_save_flags())
 119 #define restore_flags(x) __global_restore_flags(x)
 120 #define save_and_cli(x) do { save_flags(x); cli(); } while(0)
 121
 122 #else
 123
 124 #define cli() __cli()
 125 #define sti() __sti()
 126 #define save_flags(x) __save_flags(x)
 127 #define restore_flags(x) __restore_flags(x)
 128 #define save_and_cli(x) __save_and_cli(x)
 129
 130 #endif /* CONFIG_SMP */
 131
 132 /* For spinlocks etc */
 133 #define local_irq_save(x)       __save_and_cli(x);
 134 #define local_irq_restore(x)    __restore_flags(x);
 135 #define local_irq_disable()     __cli();
 136 #define local_irq_enable()      __sti();
 137
 138 /*
 139  * These are probably defined overly paranoid ...
 140  */
 141 #define mb()                                            \
 142 __asm__ __volatile__(                                   \
 143         "# prevent instructions being moved around\n\t" \
 144         ".set\tnoreorder\n\t"                           \
 145         "# 8 nops to fool the R4400 pipeline\n\t"       \
 146         "nop;nop;nop;nop;nop;nop;nop;nop\n\t"           \
 147         ".set\treorder"                                 \
 148         : /* no output */                               \
 149         : /* no input */                                \
 150         : "memory")
 151 #define rmb() mb()
 152 #define wmb() mb()
 153
 154 #define set_mb(var, value) \
 155 do { var = value; mb(); } while (0)
 156
 157 #define set_wmb(var, value) \
 158 do { var = value; wmb(); } while (0)
 159
 160 #if !defined (_LANGUAGE_ASSEMBLY)
 161 /*
 162  * switch_to(n) should switch tasks to task nr n, first
 163  * checking that n isn't the current task, in which case it does nothing.
 164  */
 165 extern asmlinkage void *resume(void *last, void *next);
 166 #endif /* !defined (_LANGUAGE_ASSEMBLY) */
 167
 168 #define prepare_to_switch()     do { } while(0)
 169
 170 extern asmlinkage void lazy_fpu_switch(void *, void *);
 171 extern asmlinkage void init_fpu(void);
 172 extern asmlinkage void save_fp(void *);
 173
 174 #ifdef CONFIG_SMP
 175 #define SWITCH_DO_LAZY_FPU \
 176         if (prev->flags & PF_USEDFPU) { \
 177                 lazy_fpu_switch(prev, 0); \
 178                 set_cp0_status(ST0_CU1, ~ST0_CU1); \
 179                 prev->flags &= ~PF_USEDFPU; \
 180         }
 181 #else /* CONFIG_SMP */
 182 #define SWITCH_DO_LAZY_FPU      do { } while(0)
 183 #endif /* CONFIG_SMP */
 184
 185 #define switch_to(prev,next,last) \
 186 do { \
 187         SWITCH_DO_LAZY_FPU; \
 188         (last) = resume(prev, next); \
 189 } while(0)
 190
 191 extern __inline__ unsigned long xchg_u32(volatile int * m, unsigned long val)
 192 {
 193         unsigned long dummy;
 194
 195         __asm__ __volatile__(
 196                 ".set\tnoreorder\n\t"
 197                 ".set\tnoat\n\t"
 198                 "ll\t%0,(%1)\n"
 199                 "1:\tmove\t$1,%2\n\t"
 200                 "sc\t$1,(%1)\n\t"
 201                 "beqzl\t$1,1b\n\t"
 202                 "lld\t%0,(%1)\n\t"
 203                 ".set\tat\n\t"
 204                 ".set\treorder"
 205                 : "=r" (val), "=r" (m), "=r" (dummy)
 206                 : "1" (m), "2" (val)
 207                 : "memory");
 208
 209         return val;
 210 }
 211
 212 /*
 213  * Only used for 64 bit kernel.
 214  */
 215 extern __inline__ unsigned long xchg_u64(volatile long * m, unsigned long val)
 216 {
 217         unsigned long dummy;
 218
 219         __asm__ __volatile__(
 220                 ".set\tnoreorder\n\t"
 221                 ".set\tnoat\n\t"
 222                 "lld\t%0,(%1)\n"
 223                 "1:\tmove\t$1,%2\n\t"
 224                 "scd\t$1,(%1)\n\t"
 225                 "beqzl\t$1,1b\n\t"
 226                 "lld\t%0,(%1)\n\t"
 227                 ".set\tat\n\t"
 228                 ".set\treorder"
 229                 : "=r" (val), "=r" (m), "=r" (dummy)
 230                 : "1" (m), "2" (val)
 231                 : "memory");
 232
 233         return val;
 234 }
 235
 236 #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
 237 #define tas(ptr) (xchg((ptr),1))
 238
 239 /* This function doesn't exist, so you'll get a linker error if something
 240    tries to do an invalid xchg().  */
 241 extern void __xchg_called_with_bad_pointer(void);
 242
 243 static __inline__ unsigned long __xchg(unsigned long x, volatile void * ptr, int size)
 244 {
 245         switch (size) {
 246                 case 4:
 247                         return xchg_u32(ptr, x);
 248                 case 8:
 249                         return xchg_u64(ptr, x);
 250         }
 251         __xchg_called_with_bad_pointer();
 252         return x;
 253 }
 254
 255 extern void set_except_vector(int n, void *addr);
 256
 257 #endif /* _ASM_SYSTEM_H */