include/asm-sh/system.h

   1 #ifndef __ASM_SH_SYSTEM_H
   2 #define __ASM_SH_SYSTEM_H
   3
   4 /*
   5  * Copyright (C) 1999, 2000  Niibe Yutaka  &  Kaz Kojima
   6  * Copyright (C) 2002 Paul Mundt
   7  */
   8
   9 #include <asm/types.h>
  10
  11 /*
  12  *      switch_to() should switch tasks to task nr n, first
  13  */
  14
  15 #define switch_to(prev, next, last) do {                                \
  16  struct task_struct *__last;                                            \
  17  register unsigned long *__ts1 __asm__ ("r1") = &prev->thread.sp;       \
  18  register unsigned long *__ts2 __asm__ ("r2") = &prev->thread.pc;       \
  19  register unsigned long *__ts4 __asm__ ("r4") = (unsigned long *)prev;  \
  20  register unsigned long *__ts5 __asm__ ("r5") = (unsigned long *)next;  \
  21  register unsigned long *__ts6 __asm__ ("r6") = &next->thread.sp;       \
  22  register unsigned long __ts7 __asm__ ("r7") = next->thread.pc;         \
  23  __asm__ __volatile__ (".balign 4\n\t"                                  \
  24                        "stc.l   gbr, @-r15\n\t"                         \
  25                        "sts.l   pr, @-r15\n\t"                          \
  26                        "mov.l   r8, @-r15\n\t"                          \
  27                        "mov.l   r9, @-r15\n\t"                          \
  28                        "mov.l   r10, @-r15\n\t"                         \
  29                        "mov.l   r11, @-r15\n\t"                         \
  30                        "mov.l   r12, @-r15\n\t"                         \
  31                        "mov.l   r13, @-r15\n\t"                         \
  32                        "mov.l   r14, @-r15\n\t"                         \
  33                        "mov.l   r15, @r1        ! save SP\n\t"          \
  34                        "mov.l   @r6, r15        ! change to new stack\n\t" \
  35                        "mova    1f, %0\n\t"                             \
  36                        "mov.l   %0, @r2         ! save PC\n\t"          \
  37                        "mov.l   2f, %0\n\t"                             \
  38                        "jmp     @%0             ! call __switch_to\n\t" \
  39                        " lds    r7, pr          !  with return to new PC\n\t" \
  40                        ".balign 4\n"                                    \
  41                        "2:\n\t"                                         \
  42                        ".long   __switch_to\n"                          \
  43                        "1:\n\t"                                         \
  44                        "mov.l   @r15+, r14\n\t"                         \
  45                        "mov.l   @r15+, r13\n\t"                         \
  46                        "mov.l   @r15+, r12\n\t"                         \
  47                        "mov.l   @r15+, r11\n\t"                         \
  48                        "mov.l   @r15+, r10\n\t"                         \
  49                        "mov.l   @r15+, r9\n\t"                          \
  50                        "mov.l   @r15+, r8\n\t"                          \
  51                        "lds.l   @r15+, pr\n\t"                          \
  52                        "ldc.l   @r15+, gbr\n\t"                         \
  53                        : "=z" (__last)                                  \
  54                        : "r" (__ts1), "r" (__ts2), "r" (__ts4),         \
  55                          "r" (__ts5), "r" (__ts6), "r" (__ts7)          \
  56                        : "r3", "t");                                    \
  57         last = __last;                                                  \
  58 } while (0)
  59
  60 /*
  61  * On SMP systems, when the scheduler does migration-cost autodetection,
  62  * it needs a way to flush as much of the CPU's caches as possible.
  63  *
  64  * TODO: fill this in!
  65  */
  66 static inline void sched_cacheflush(void)
  67 {
  68 }
  69
  70 #define nop() __asm__ __volatile__ ("nop")
  71
  72
  73 #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
  74
  75 static __inline__ unsigned long tas(volatile int *m)
  76 { /* #define tas(ptr) (xchg((ptr),1)) */
  77         unsigned long retval;
  78
  79         __asm__ __volatile__ ("tas.b    @%1\n\t"
  80                               "movt     %0"
  81                               : "=r" (retval): "r" (m): "t", "memory");
  82         return retval;
  83 }
  84
  85 extern void __xchg_called_with_bad_pointer(void);
  86
  87 #define mb()    __asm__ __volatile__ ("": : :"memory")
  88 #define rmb()   mb()
  89 #define wmb()   __asm__ __volatile__ ("": : :"memory")
  90 #define read_barrier_depends()  do { } while(0)
  91
  92 #ifdef CONFIG_SMP
  93 #define smp_mb()        mb()
  94 #define smp_rmb()       rmb()
  95 #define smp_wmb()       wmb()
  96 #define smp_read_barrier_depends()      read_barrier_depends()
  97 #else
  98 #define smp_mb()        barrier()
  99 #define smp_rmb()       barrier()
 100 #define smp_wmb()       barrier()
 101 #define smp_read_barrier_depends()      do { } while(0)
 102 #endif
 103
 104 #define set_mb(var, value) do { xchg(&var, value); } while (0)
 105
 106 /* Interrupt Control */
 107 static __inline__ void local_irq_enable(void)
 108 {
 109         unsigned long __dummy0, __dummy1;
 110
 111         __asm__ __volatile__("stc       sr, %0\n\t"
 112                              "and       %1, %0\n\t"
 113                              "stc       r6_bank, %1\n\t"
 114                              "or        %1, %0\n\t"
 115                              "ldc       %0, sr"
 116                              : "=&r" (__dummy0), "=r" (__dummy1)
 117                              : "1" (~0x000000f0)
 118                              : "memory");
 119 }
 120
 121 static __inline__ void local_irq_disable(void)
 122 {
 123         unsigned long __dummy;
 124         __asm__ __volatile__("stc       sr, %0\n\t"
 125                              "or        #0xf0, %0\n\t"
 126                              "ldc       %0, sr"
 127                              : "=&z" (__dummy)
 128                              : /* no inputs */
 129                              : "memory");
 130 }
 131
 132 #define local_save_flags(x) \
 133         __asm__("stc sr, %0; and #0xf0, %0" : "=&z" (x) :/**/: "memory" )
 134
 135 #define irqs_disabled()                 \
 136 ({                                      \
 137         unsigned long flags;            \
 138         local_save_flags(flags);        \
 139         (flags != 0);                   \
 140 })
 141
 142 static __inline__ unsigned long local_irq_save(void)
 143 {
 144         unsigned long flags, __dummy;
 145
 146         __asm__ __volatile__("stc       sr, %1\n\t"
 147                              "mov       %1, %0\n\t"
 148                              "or        #0xf0, %0\n\t"
 149                              "ldc       %0, sr\n\t"
 150                              "mov       %1, %0\n\t"
 151                              "and       #0xf0, %0"
 152                              : "=&z" (flags), "=&r" (__dummy)
 153                              :/**/
 154                              : "memory" );
 155         return flags;
 156 }
 157
 158 #ifdef DEBUG_CLI_STI
 159 static __inline__ void  local_irq_restore(unsigned long x)
 160 {
 161         if ((x & 0x000000f0) != 0x000000f0)
 162                 local_irq_enable();
 163         else {
 164                 unsigned long flags;
 165                 local_save_flags(flags);
 166
 167                 if (flags == 0) {
 168                         extern void dump_stack(void);
 169                         printk(KERN_ERR "BUG!\n");
 170                         dump_stack();
 171                         local_irq_disable();
 172                 }
 173         }
 174 }
 175 #else
 176 #define local_irq_restore(x) do {                       \
 177         if ((x & 0x000000f0) != 0x000000f0)             \
 178                 local_irq_enable();                             \
 179 } while (0)
 180 #endif
 181
 182 #define really_restore_flags(x) do {                    \
 183         if ((x & 0x000000f0) != 0x000000f0)             \
 184                 local_irq_enable();                             \
 185         else                                            \
 186                 local_irq_disable();                            \
 187 } while (0)
 188
 189 /*
 190  * Jump to P2 area.
 191  * When handling TLB or caches, we need to do it from P2 area.
 192  */
 193 #define jump_to_P2()                    \
 194 do {                                    \
 195         unsigned long __dummy;          \
 196         __asm__ __volatile__(           \
 197                 "mov.l  1f, %0\n\t"     \
 198                 "or     %1, %0\n\t"     \
 199                 "jmp    @%0\n\t"        \
 200                 " nop\n\t"              \
 201                 ".balign 4\n"           \
 202                 "1:     .long 2f\n"     \
 203                 "2:"                    \
 204                 : "=&r" (__dummy)       \
 205                 : "r" (0x20000000));    \
 206 } while (0)
 207
 208 /*
 209  * Back to P1 area.
 210  */
 211 #define back_to_P1()                                    \
 212 do {                                                    \
 213         unsigned long __dummy;                          \
 214         __asm__ __volatile__(                           \
 215                 "nop;nop;nop;nop;nop;nop;nop\n\t"       \
 216                 "mov.l  1f, %0\n\t"                     \
 217                 "jmp    @%0\n\t"                        \
 218                 " nop\n\t"                              \
 219                 ".balign 4\n"                           \
 220                 "1:     .long 2f\n"                     \
 221                 "2:"                                    \
 222                 : "=&r" (__dummy));                     \
 223 } while (0)
 224
 225 /* For spinlocks etc */
 226 #define local_irq_save(x)       x = local_irq_save()
 227
 228 static __inline__ unsigned long xchg_u32(volatile int * m, unsigned long val)
 229 {
 230         unsigned long flags, retval;
 231
 232         local_irq_save(flags);
 233         retval = *m;
 234         *m = val;
 235         local_irq_restore(flags);
 236         return retval;
 237 }
 238
 239 static __inline__ unsigned long xchg_u8(volatile unsigned char * m, unsigned long val)
 240 {
 241         unsigned long flags, retval;
 242
 243         local_irq_save(flags);
 244         retval = *m;
 245         *m = val & 0xff;
 246         local_irq_restore(flags);
 247         return retval;
 248 }
 249
 250 static __inline__ unsigned long __xchg(unsigned long x, volatile void * ptr, int size)
 251 {
 252         switch (size) {
 253         case 4:
 254                 return xchg_u32(ptr, x);
 255                 break;
 256         case 1:
 257                 return xchg_u8(ptr, x);
 258                 break;
 259         }
 260         __xchg_called_with_bad_pointer();
 261         return x;
 262 }
 263
 264 static inline unsigned long __cmpxchg_u32(volatile int * m, unsigned long old,
 265         unsigned long new)
 266 {
 267         __u32 retval;
 268         unsigned long flags;
 269
 270         local_irq_save(flags);
 271         retval = *m;
 272         if (retval == old)
 273                 *m = new;
 274         local_irq_restore(flags);       /* implies memory barrier  */
 275         return retval;
 276 }
 277
 278 /* This function doesn't exist, so you'll get a linker error
 279  * if something tries to do an invalid cmpxchg(). */
 280 extern void __cmpxchg_called_with_bad_pointer(void);
 281
 282 #define __HAVE_ARCH_CMPXCHG 1
 283
 284 static inline unsigned long __cmpxchg(volatile void * ptr, unsigned long old,
 285                 unsigned long new, int size)
 286 {
 287         switch (size) {
 288         case 4:
 289                 return __cmpxchg_u32(ptr, old, new);
 290         }
 291         __cmpxchg_called_with_bad_pointer();
 292         return old;
 293 }
 294
 295 #define cmpxchg(ptr,o,n)                                                 \
 296   ({                                                                     \
 297      __typeof__(*(ptr)) _o_ = (o);                                       \
 298      __typeof__(*(ptr)) _n_ = (n);                                       \
 299      (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,           \
 300                                     (unsigned long)_n_, sizeof(*(ptr))); \
 301   })
 302
 303 /* XXX
 304  * disable hlt during certain critical i/o operations
 305  */
 306 #define HAVE_DISABLE_HLT
 307 void disable_hlt(void);
 308 void enable_hlt(void);
 309
 310 #define arch_align_stack(x) (x)
 311
 312 #endif