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