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