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 #define nop() __asm__ __volatile__ ("nop")
  61
  62
  63 #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
  64
  65 static __inline__ unsigned long tas(volatile int *m)
  66 { /* #define tas(ptr) (xchg((ptr),1)) */
  67         unsigned long retval;
  68
  69         __asm__ __volatile__ ("tas.b    @%1\n\t"
  70                               "movt     %0"
  71                               : "=r" (retval): "r" (m): "t", "memory");
  72         return retval;
  73 }
  74
  75 extern void __xchg_called_with_bad_pointer(void);
  76
  77 #define mb()    __asm__ __volatile__ ("": : :"memory")
  78 #define rmb()   mb()
  79 #define wmb()   __asm__ __volatile__ ("": : :"memory")
  80 #define read_barrier_depends()  do { } while(0)
  81
  82 #ifdef CONFIG_SMP
  83 #define smp_mb()        mb()
  84 #define smp_rmb()       rmb()
  85 #define smp_wmb()       wmb()
  86 #define smp_read_barrier_depends()      read_barrier_depends()
  87 #else
  88 #define smp_mb()        barrier()
  89 #define smp_rmb()       barrier()
  90 #define smp_wmb()       barrier()
  91 #define smp_read_barrier_depends()      do { } while(0)
  92 #endif
  93
  94 #define set_mb(var, value) do { xchg(&var, value); } while (0)
  95 #define set_wmb(var, value) do { var = value; wmb(); } while (0)
  96
  97 /* Interrupt Control */
  98 static __inline__ void local_irq_enable(void)
  99 {
 100         unsigned long __dummy0, __dummy1;
 101
 102         __asm__ __volatile__("stc       sr, %0\n\t"
 103                              "and       %1, %0\n\t"
 104                              "stc       r6_bank, %1\n\t"
 105                              "or        %1, %0\n\t"
 106                              "ldc       %0, sr"
 107                              : "=&r" (__dummy0), "=r" (__dummy1)
 108                              : "1" (~0x000000f0)
 109                              : "memory");
 110 }
 111
 112 static __inline__ void local_irq_disable(void)
 113 {
 114         unsigned long __dummy;
 115         __asm__ __volatile__("stc       sr, %0\n\t"
 116                              "or        #0xf0, %0\n\t"
 117                              "ldc       %0, sr"
 118                              : "=&z" (__dummy)
 119                              : /* no inputs */
 120                              : "memory");
 121 }
 122
 123 #define local_save_flags(x) \
 124         __asm__("stc sr, %0; and #0xf0, %0" : "=&z" (x) :/**/: "memory" )
 125
 126 #define irqs_disabled()                 \
 127 ({                                      \
 128         unsigned long flags;            \
 129         local_save_flags(flags);        \
 130         (flags != 0);                   \
 131 })
 132
 133 static __inline__ unsigned long local_irq_save(void)
 134 {
 135         unsigned long flags, __dummy;
 136
 137         __asm__ __volatile__("stc       sr, %1\n\t"
 138                              "mov       %1, %0\n\t"
 139                              "or        #0xf0, %0\n\t"
 140                              "ldc       %0, sr\n\t"
 141                              "mov       %1, %0\n\t"
 142                              "and       #0xf0, %0"
 143                              : "=&z" (flags), "=&r" (__dummy)
 144                              :/**/
 145                              : "memory" );
 146         return flags;
 147 }
 148
 149 #ifdef DEBUG_CLI_STI
 150 static __inline__ void  local_irq_restore(unsigned long x)
 151 {
 152         if ((x & 0x000000f0) != 0x000000f0)
 153                 local_irq_enable();
 154         else {
 155                 unsigned long flags;
 156                 local_save_flags(flags);
 157
 158                 if (flags == 0) {
 159                         extern void dump_stack(void);
 160                         printk(KERN_ERR "BUG!\n");
 161                         dump_stack();
 162                         local_irq_disable();
 163                 }
 164         }
 165 }
 166 #else
 167 #define local_irq_restore(x) do {                       \
 168         if ((x & 0x000000f0) != 0x000000f0)             \
 169                 local_irq_enable();                             \
 170 } while (0)
 171 #endif
 172
 173 #define really_restore_flags(x) do {                    \
 174         if ((x & 0x000000f0) != 0x000000f0)             \
 175                 local_irq_enable();                             \
 176         else                                            \
 177                 local_irq_disable();                            \
 178 } while (0)
 179
 180 /*
 181  * Jump to P2 area.
 182  * When handling TLB or caches, we need to do it from P2 area.
 183  */
 184 #define jump_to_P2()                    \
 185 do {                                    \
 186         unsigned long __dummy;          \
 187         __asm__ __volatile__(           \
 188                 "mov.l  1f, %0\n\t"     \
 189                 "or     %1, %0\n\t"     \
 190                 "jmp    @%0\n\t"        \
 191                 " nop\n\t"              \
 192                 ".balign 4\n"           \
 193                 "1:     .long 2f\n"     \
 194                 "2:"                    \
 195                 : "=&r" (__dummy)       \
 196                 : "r" (0x20000000));    \
 197 } while (0)
 198
 199 /*
 200  * Back to P1 area.
 201  */
 202 #define back_to_P1()                                    \
 203 do {                                                    \
 204         unsigned long __dummy;                          \
 205         __asm__ __volatile__(                           \
 206                 "nop;nop;nop;nop;nop;nop;nop\n\t"       \
 207                 "mov.l  1f, %0\n\t"                     \
 208                 "jmp    @%0\n\t"                        \
 209                 " nop\n\t"                              \
 210                 ".balign 4\n"                           \
 211                 "1:     .long 2f\n"                     \
 212                 "2:"                                    \
 213                 : "=&r" (__dummy));                     \
 214 } while (0)
 215
 216 /* For spinlocks etc */
 217 #define local_irq_save(x)       x = local_irq_save()
 218
 219 static __inline__ unsigned long xchg_u32(volatile int * m, unsigned long val)
 220 {
 221         unsigned long flags, retval;
 222
 223         local_irq_save(flags);
 224         retval = *m;
 225         *m = val;
 226         local_irq_restore(flags);
 227         return retval;
 228 }
 229
 230 static __inline__ unsigned long xchg_u8(volatile unsigned char * m, unsigned long val)
 231 {
 232         unsigned long flags, retval;
 233
 234         local_irq_save(flags);
 235         retval = *m;
 236         *m = val & 0xff;
 237         local_irq_restore(flags);
 238         return retval;
 239 }
 240
 241 static __inline__ unsigned long __xchg(unsigned long x, volatile void * ptr, int size)
 242 {
 243         switch (size) {
 244         case 4:
 245                 return xchg_u32(ptr, x);
 246                 break;
 247         case 1:
 248                 return xchg_u8(ptr, x);
 249                 break;
 250         }
 251         __xchg_called_with_bad_pointer();
 252         return x;
 253 }
 254
 255 /* XXX
 256  * disable hlt during certain critical i/o operations
 257  */
 258 #define HAVE_DISABLE_HLT
 259 void disable_hlt(void);
 260 void enable_hlt(void);
 261
 262 #define arch_align_stack(x) (x)
 263
 264 #endif