include/asm-ppc/system.h

   1 /*
   2  * Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
   3  */
   4 #ifndef __PPC_SYSTEM_H
   5 #define __PPC_SYSTEM_H
   6
   7 #include <linux/kernel.h>
   8
   9 #include <asm/hw_irq.h>
  10
  11 /*
  12  * Memory barrier.
  13  * The sync instruction guarantees that all memory accesses initiated
  14  * by this processor have been performed (with respect to all other
  15  * mechanisms that access memory).  The eieio instruction is a barrier
  16  * providing an ordering (separately) for (a) cacheable stores and (b)
  17  * loads and stores to non-cacheable memory (e.g. I/O devices).
  18  *
  19  * mb() prevents loads and stores being reordered across this point.
  20  * rmb() prevents loads being reordered across this point.
  21  * wmb() prevents stores being reordered across this point.
  22  * read_barrier_depends() prevents data-dependent loads being reordered
  23  *      across this point (nop on PPC).
  24  *
  25  * We can use the eieio instruction for wmb, but since it doesn't
  26  * give any ordering guarantees about loads, we have to use the
  27  * stronger but slower sync instruction for mb and rmb.
  28  */
  29 #define mb()  __asm__ __volatile__ ("sync" : : : "memory")
  30 #define rmb()  __asm__ __volatile__ ("sync" : : : "memory")
  31 #define wmb()  __asm__ __volatile__ ("eieio" : : : "memory")
  32 #define read_barrier_depends()  do { } while(0)
  33
  34 #define set_mb(var, value)      do { var = value; mb(); } while (0)
  35
  36 #ifdef CONFIG_SMP
  37 #define smp_mb()        mb()
  38 #define smp_rmb()       rmb()
  39 #define smp_wmb()       __asm__ __volatile__ ("eieio" : : : "memory")
  40 #define smp_read_barrier_depends()      read_barrier_depends()
  41 #else
  42 #define smp_mb()        barrier()
  43 #define smp_rmb()       barrier()
  44 #define smp_wmb()       barrier()
  45 #define smp_read_barrier_depends()      do { } while(0)
  46 #endif /* CONFIG_SMP */
  47
  48 #ifdef __KERNEL__
  49 struct task_struct;
  50 struct pt_regs;
  51
  52 extern void print_backtrace(unsigned long *);
  53 extern void show_regs(struct pt_regs * regs);
  54 extern void flush_instruction_cache(void);
  55 extern void hard_reset_now(void);
  56 extern void poweroff_now(void);
  57 #ifdef CONFIG_6xx
  58 extern long _get_L2CR(void);
  59 extern long _get_L3CR(void);
  60 extern void _set_L2CR(unsigned long);
  61 extern void _set_L3CR(unsigned long);
  62 #else
  63 #define _get_L2CR()     0L
  64 #define _get_L3CR()     0L
  65 #define _set_L2CR(val)  do { } while(0)
  66 #define _set_L3CR(val)  do { } while(0)
  67 #endif
  68 extern void via_cuda_init(void);
  69 extern void pmac_nvram_init(void);
  70 extern void chrp_nvram_init(void);
  71 extern void read_rtc_time(void);
  72 extern void pmac_find_display(void);
  73 extern void giveup_fpu(struct task_struct *);
  74 extern void disable_kernel_fp(void);
  75 extern void enable_kernel_fp(void);
  76 extern void flush_fp_to_thread(struct task_struct *);
  77 extern void enable_kernel_altivec(void);
  78 extern void giveup_altivec(struct task_struct *);
  79 extern void load_up_altivec(struct task_struct *);
  80 extern int emulate_altivec(struct pt_regs *);
  81 extern void giveup_spe(struct task_struct *);
  82 extern void load_up_spe(struct task_struct *);
  83 extern int fix_alignment(struct pt_regs *);
  84 extern void cvt_fd(float *from, double *to, struct thread_struct *thread);
  85 extern void cvt_df(double *from, float *to, struct thread_struct *thread);
  86
  87 #ifndef CONFIG_SMP
  88 extern void discard_lazy_cpu_state(void);
  89 #else
  90 static inline void discard_lazy_cpu_state(void)
  91 {
  92 }
  93 #endif
  94
  95 #ifdef CONFIG_ALTIVEC
  96 extern void flush_altivec_to_thread(struct task_struct *);
  97 #else
  98 static inline void flush_altivec_to_thread(struct task_struct *t)
  99 {
 100 }
 101 #endif
 102
 103 #ifdef CONFIG_SPE
 104 extern void flush_spe_to_thread(struct task_struct *);
 105 #else
 106 static inline void flush_spe_to_thread(struct task_struct *t)
 107 {
 108 }
 109 #endif
 110
 111 extern int call_rtas(const char *, int, int, unsigned long *, ...);
 112 extern void cacheable_memzero(void *p, unsigned int nb);
 113 extern void *cacheable_memcpy(void *, const void *, unsigned int);
 114 extern int do_page_fault(struct pt_regs *, unsigned long, unsigned long);
 115 extern void bad_page_fault(struct pt_regs *, unsigned long, int);
 116 extern int die(const char *, struct pt_regs *, long);
 117 extern void _exception(int, struct pt_regs *, int, unsigned long);
 118 void _nmask_and_or_msr(unsigned long nmask, unsigned long or_val);
 119
 120 #ifdef CONFIG_BOOKE_WDT
 121 extern u32 booke_wdt_enabled;
 122 extern u32 booke_wdt_period;
 123 #endif /* CONFIG_BOOKE_WDT */
 124
 125 struct device_node;
 126 extern void note_scsi_host(struct device_node *, void *);
 127
 128 extern struct task_struct *__switch_to(struct task_struct *,
 129         struct task_struct *);
 130 #define switch_to(prev, next, last)     ((last) = __switch_to((prev), (next)))
 131
 132 /*
 133  * On SMP systems, when the scheduler does migration-cost autodetection,
 134  * it needs a way to flush as much of the CPU's caches as possible.
 135  *
 136  * TODO: fill this in!
 137  */
 138 static inline void sched_cacheflush(void)
 139 {
 140 }
 141
 142 struct thread_struct;
 143 extern struct task_struct *_switch(struct thread_struct *prev,
 144                                    struct thread_struct *next);
 145
 146 extern unsigned int rtas_data;
 147
 148 static __inline__ unsigned long
 149 xchg_u32(volatile void *p, unsigned long val)
 150 {
 151         unsigned long prev;
 152
 153         __asm__ __volatile__ ("\n\
 154 1:      lwarx   %0,0,%2 \n"
 155         PPC405_ERR77(0,%2)
 156 "       stwcx.  %3,0,%2 \n\
 157         bne-    1b"
 158         : "=&r" (prev), "=m" (*(volatile unsigned long *)p)
 159         : "r" (p), "r" (val), "m" (*(volatile unsigned long *)p)
 160         : "cc", "memory");
 161
 162         return prev;
 163 }
 164
 165 /*
 166  * This function doesn't exist, so you'll get a linker error
 167  * if something tries to do an invalid xchg().
 168  */
 169 extern void __xchg_called_with_bad_pointer(void);
 170
 171 #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
 172
 173 static inline unsigned long __xchg(unsigned long x, volatile void *ptr, int size)
 174 {
 175         switch (size) {
 176         case 4:
 177                 return (unsigned long) xchg_u32(ptr, x);
 178 #if 0   /* xchg_u64 doesn't exist on 32-bit PPC */
 179         case 8:
 180                 return (unsigned long) xchg_u64(ptr, x);
 181 #endif /* 0 */
 182         }
 183         __xchg_called_with_bad_pointer();
 184         return x;
 185
 186
 187 }
 188
 189 extern inline void * xchg_ptr(void * m, void * val)
 190 {
 191         return (void *) xchg_u32(m, (unsigned long) val);
 192 }
 193
 194
 195 #define __HAVE_ARCH_CMPXCHG     1
 196
 197 static __inline__ unsigned long
 198 __cmpxchg_u32(volatile unsigned int *p, unsigned int old, unsigned int new)
 199 {
 200         unsigned int prev;
 201
 202         __asm__ __volatile__ ("\n\
 203 1:      lwarx   %0,0,%2 \n\
 204         cmpw    0,%0,%3 \n\
 205         bne     2f \n"
 206         PPC405_ERR77(0,%2)
 207 "       stwcx.  %4,0,%2 \n\
 208         bne-    1b\n"
 209 #ifdef CONFIG_SMP
 210 "       sync\n"
 211 #endif /* CONFIG_SMP */
 212 "2:"
 213         : "=&r" (prev), "=m" (*p)
 214         : "r" (p), "r" (old), "r" (new), "m" (*p)
 215         : "cc", "memory");
 216
 217         return prev;
 218 }
 219
 220 /* This function doesn't exist, so you'll get a linker error
 221    if something tries to do an invalid cmpxchg().  */
 222 extern void __cmpxchg_called_with_bad_pointer(void);
 223
 224 static __inline__ unsigned long
 225 __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
 226 {
 227         switch (size) {
 228         case 4:
 229                 return __cmpxchg_u32(ptr, old, new);
 230 #if 0   /* we don't have __cmpxchg_u64 on 32-bit PPC */
 231         case 8:
 232                 return __cmpxchg_u64(ptr, old, new);
 233 #endif /* 0 */
 234         }
 235         __cmpxchg_called_with_bad_pointer();
 236         return old;
 237 }
 238
 239 #define cmpxchg(ptr,o,n)                                                 \
 240   ({                                                                     \
 241      __typeof__(*(ptr)) _o_ = (o);                                       \
 242      __typeof__(*(ptr)) _n_ = (n);                                       \
 243      (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,           \
 244                                     (unsigned long)_n_, sizeof(*(ptr))); \
 245   })
 246
 247 #define arch_align_stack(x) (x)
 248
 249 #endif /* __KERNEL__ */
 250 #endif /* __PPC_SYSTEM_H */