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 <linux/config.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  task_t *__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 #define set_wmb(var, value) do { var = value; wmb(); } while (0)
 106
 107 /* Interrupt Control */
 108 static __inline__ void local_irq_enable(void)
 109 {
 110         unsigned long __dummy0, __dummy1;
 111
 112         __asm__ __volatile__("stc       sr, %0\n\t"
 113                              "and       %1, %0\n\t"
 114                              "stc       r6_bank, %1\n\t"
 115                              "or        %1, %0\n\t"
 116                              "ldc       %0, sr"
 117                              : "=&r" (__dummy0), "=r" (__dummy1)
 118                              : "1" (~0x000000f0)
 119                              : "memory");
 120 }
 121
 122 static __inline__ void local_irq_disable(void)
 123 {
 124         unsigned long __dummy;
 125         __asm__ __volatile__("stc       sr, %0\n\t"
 126                              "or        #0xf0, %0\n\t"
 127                              "ldc       %0, sr"
 128                              : "=&z" (__dummy)
 129                              : /* no inputs */
 130                              : "memory");
 131 }
 132
 133 #define local_save_flags(x) \
 134         __asm__("stc sr, %0; and #0xf0, %0" : "=&z" (x) :/**/: "memory" )
 135
 136 #define irqs_disabled()                 \
 137 ({                                      \
 138         unsigned long flags;            \
 139         local_save_flags(flags);        \
 140         (flags != 0);                   \
 141 })
 142
 143 static __inline__ unsigned long local_irq_save(void)
 144 {
 145         unsigned long flags, __dummy;
 146
 147         __asm__ __volatile__("stc       sr, %1\n\t"
 148                              "mov       %1, %0\n\t"
 149                              "or        #0xf0, %0\n\t"
 150                              "ldc       %0, sr\n\t"
 151                              "mov       %1, %0\n\t"
 152                              "and       #0xf0, %0"
 153                              : "=&z" (flags), "=&r" (__dummy)
 154                              :/**/
 155                              : "memory" );
 156         return flags;
 157 }
 158
 159 #ifdef DEBUG_CLI_STI
 160 static __inline__ void  local_irq_restore(unsigned long x)
 161 {
 162         if ((x & 0x000000f0) != 0x000000f0)
 163                 local_irq_enable();
 164         else {
 165                 unsigned long flags;
 166                 local_save_flags(flags);
 167
 168                 if (flags == 0) {
 169                         extern void dump_stack(void);
 170                         printk(KERN_ERR "BUG!\n");
 171                         dump_stack();
 172                         local_irq_disable();
 173                 }
 174         }
 175 }
 176 #else
 177 #define local_irq_restore(x) do {                       \
 178         if ((x & 0x000000f0) != 0x000000f0)             \
 179                 local_irq_enable();                             \
 180 } while (0)
 181 #endif
 182
 183 #define really_restore_flags(x) do {                    \
 184         if ((x & 0x000000f0) != 0x000000f0)             \
 185                 local_irq_enable();                             \
 186         else                                            \
 187                 local_irq_disable();                            \
 188 } while (0)
 189
 190 /*
 191  * Jump to P2 area.
 192  * When handling TLB or caches, we need to do it from P2 area.
 193  */
 194 #define jump_to_P2()                    \
 195 do {                                    \
 196         unsigned long __dummy;          \
 197         __asm__ __volatile__(           \
 198                 "mov.l  1f, %0\n\t"     \
 199                 "or     %1, %0\n\t"     \
 200                 "jmp    @%0\n\t"        \
 201                 " nop\n\t"              \
 202                 ".balign 4\n"           \
 203                 "1:     .long 2f\n"     \
 204                 "2:"                    \
 205                 : "=&r" (__dummy)       \
 206                 : "r" (0x20000000));    \
 207 } while (0)
 208
 209 /*
 210  * Back to P1 area.
 211  */
 212 #define back_to_P1()                                    \
 213 do {                                                    \
 214         unsigned long __dummy;                          \
 215         __asm__ __volatile__(                           \
 216                 "nop;nop;nop;nop;nop;nop;nop\n\t"       \
 217                 "mov.l  1f, %0\n\t"                     \
 218                 "jmp    @%0\n\t"                        \
 219                 " nop\n\t"                              \
 220                 ".balign 4\n"                           \
 221                 "1:     .long 2f\n"                     \
 222                 "2:"                                    \
 223                 : "=&r" (__dummy));                     \
 224 } while (0)
 225
 226 /* For spinlocks etc */
 227 #define local_irq_save(x)       x = local_irq_save()
 228
 229 static __inline__ unsigned long xchg_u32(volatile int * m, unsigned long val)
 230 {
 231         unsigned long flags, retval;
 232
 233         local_irq_save(flags);
 234         retval = *m;
 235         *m = val;
 236         local_irq_restore(flags);
 237         return retval;
 238 }
 239
 240 static __inline__ unsigned long xchg_u8(volatile unsigned char * m, unsigned long val)
 241 {
 242         unsigned long flags, retval;
 243
 244         local_irq_save(flags);
 245         retval = *m;
 246         *m = val & 0xff;
 247         local_irq_restore(flags);
 248         return retval;
 249 }
 250
 251 static __inline__ unsigned long __xchg(unsigned long x, volatile void * ptr, int size)
 252 {
 253         switch (size) {
 254         case 4:
 255                 return xchg_u32(ptr, x);
 256                 break;
 257         case 1:
 258                 return xchg_u8(ptr, x);
 259                 break;
 260         }
 261         __xchg_called_with_bad_pointer();
 262         return x;
 263 }
 264
 265 /* XXX
 266  * disable hlt during certain critical i/o operations
 267  */
 268 #define HAVE_DISABLE_HLT
 269 void disable_hlt(void);
 270 void enable_hlt(void);
 271
 272 #define arch_align_stack(x) (x)
 273
 274 #endif