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 #define AT_VECTOR_SIZE_ARCH 6 /* entries in ARCH_DLINFO */
  37 #ifdef CONFIG_SMP
  38 #define smp_mb()        mb()
  39 #define smp_rmb()       rmb()
  40 #define smp_wmb()       __asm__ __volatile__ ("eieio" : : : "memory")
  41 #define smp_read_barrier_depends()      read_barrier_depends()
  42 #else
  43 #define smp_mb()        barrier()
  44 #define smp_rmb()       barrier()
  45 #define smp_wmb()       barrier()
  46 #define smp_read_barrier_depends()      do { } while(0)
  47 #endif /* CONFIG_SMP */
  48
  49 #ifdef __KERNEL__
  50 struct task_struct;
  51 struct pt_regs;
  52
  53 extern void print_backtrace(unsigned long *);
  54 extern void show_regs(struct pt_regs * regs);
  55 extern void flush_instruction_cache(void);
  56 extern void hard_reset_now(void);
  57 extern void poweroff_now(void);
  58 extern int set_dabr(unsigned long dabr);
  59 #ifdef CONFIG_6xx
  60 extern long _get_L2CR(void);
  61 extern long _get_L3CR(void);
  62 extern void _set_L2CR(unsigned long);
  63 extern void _set_L3CR(unsigned long);
  64 #else
  65 #define _get_L2CR()     0L
  66 #define _get_L3CR()     0L
  67 #define _set_L2CR(val)  do { } while(0)
  68 #define _set_L3CR(val)  do { } while(0)
  69 #endif
  70 extern void via_cuda_init(void);
  71 extern void pmac_nvram_init(void);
  72 extern void chrp_nvram_init(void);
  73 extern void read_rtc_time(void);
  74 extern void pmac_find_display(void);
  75 extern void giveup_fpu(struct task_struct *);
  76 extern void disable_kernel_fp(void);
  77 extern void enable_kernel_fp(void);
  78 extern void flush_fp_to_thread(struct task_struct *);
  79 extern void enable_kernel_altivec(void);
  80 extern void giveup_altivec(struct task_struct *);
  81 extern void load_up_altivec(struct task_struct *);
  82 extern int emulate_altivec(struct pt_regs *);
  83 extern void giveup_spe(struct task_struct *);
  84 extern void load_up_spe(struct task_struct *);
  85 extern int fix_alignment(struct pt_regs *);
  86 extern void cvt_fd(float *from, double *to, struct thread_struct *thread);
  87 extern void cvt_df(double *from, float *to, struct thread_struct *thread);
  88
  89 #ifndef CONFIG_SMP
  90 extern void discard_lazy_cpu_state(void);
  91 #else
  92 static inline void discard_lazy_cpu_state(void)
  93 {
  94 }
  95 #endif
  96
  97 #ifdef CONFIG_ALTIVEC
  98 extern void flush_altivec_to_thread(struct task_struct *);
  99 #else
 100 static inline void flush_altivec_to_thread(struct task_struct *t)
 101 {
 102 }
 103 #endif
 104
 105 #ifdef CONFIG_SPE
 106 extern void flush_spe_to_thread(struct task_struct *);
 107 #else
 108 static inline void flush_spe_to_thread(struct task_struct *t)
 109 {
 110 }
 111 #endif
 112
 113 extern int call_rtas(const char *, int, int, unsigned long *, ...);
 114 extern void cacheable_memzero(void *p, unsigned int nb);
 115 extern void *cacheable_memcpy(void *, const void *, unsigned int);
 116 extern int do_page_fault(struct pt_regs *, unsigned long, unsigned long);
 117 extern void bad_page_fault(struct pt_regs *, unsigned long, int);
 118 extern int die(const char *, struct pt_regs *, long);
 119 extern void _exception(int, struct pt_regs *, int, unsigned long);
 120 void _nmask_and_or_msr(unsigned long nmask, unsigned long or_val);
 121
 122 #ifdef CONFIG_BOOKE_WDT
 123 extern u32 booke_wdt_enabled;
 124 extern u32 booke_wdt_period;
 125 #endif /* CONFIG_BOOKE_WDT */
 126
 127 struct device_node;
 128 extern void note_scsi_host(struct device_node *, void *);
 129
 130 extern struct task_struct *__switch_to(struct task_struct *,
 131         struct task_struct *);
 132 #define switch_to(prev, next, last)     ((last) = __switch_to((prev), (next)))
 133
 134 struct thread_struct;
 135 extern struct task_struct *_switch(struct thread_struct *prev,
 136                                    struct thread_struct *next);
 137
 138 extern unsigned int rtas_data;
 139
 140 static __inline__ unsigned long
 141 xchg_u32(volatile void *p, unsigned long val)
 142 {
 143         unsigned long prev;
 144
 145         __asm__ __volatile__ ("\n\
 146 1:      lwarx   %0,0,%2 \n"
 147         PPC405_ERR77(0,%2)
 148 "       stwcx.  %3,0,%2 \n\
 149         bne-    1b"
 150         : "=&r" (prev), "=m" (*(volatile unsigned long *)p)
 151         : "r" (p), "r" (val), "m" (*(volatile unsigned long *)p)
 152         : "cc", "memory");
 153
 154         return prev;
 155 }
 156
 157 /*
 158  * This function doesn't exist, so you'll get a linker error
 159  * if something tries to do an invalid xchg().
 160  */
 161 extern void __xchg_called_with_bad_pointer(void);
 162
 163 #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
 164
 165 static inline unsigned long __xchg(unsigned long x, volatile void *ptr, int size)
 166 {
 167         switch (size) {
 168         case 4:
 169                 return (unsigned long) xchg_u32(ptr, x);
 170 #if 0   /* xchg_u64 doesn't exist on 32-bit PPC */
 171         case 8:
 172                 return (unsigned long) xchg_u64(ptr, x);
 173 #endif /* 0 */
 174         }
 175         __xchg_called_with_bad_pointer();
 176         return x;
 177
 178
 179 }
 180
 181 extern inline void * xchg_ptr(void * m, void * val)
 182 {
 183         return (void *) xchg_u32(m, (unsigned long) val);
 184 }
 185
 186
 187 #define __HAVE_ARCH_CMPXCHG     1
 188
 189 static __inline__ unsigned long
 190 __cmpxchg_u32(volatile unsigned int *p, unsigned int old, unsigned int new)
 191 {
 192         unsigned int prev;
 193
 194         __asm__ __volatile__ ("\n\
 195 1:      lwarx   %0,0,%2 \n\
 196         cmpw    0,%0,%3 \n\
 197         bne     2f \n"
 198         PPC405_ERR77(0,%2)
 199 "       stwcx.  %4,0,%2 \n\
 200         bne-    1b\n"
 201 #ifdef CONFIG_SMP
 202 "       sync\n"
 203 #endif /* CONFIG_SMP */
 204 "2:"
 205         : "=&r" (prev), "=m" (*p)
 206         : "r" (p), "r" (old), "r" (new), "m" (*p)
 207         : "cc", "memory");
 208
 209         return prev;
 210 }
 211
 212 static inline unsigned long
 213 __cmpxchg_u32_local(volatile unsigned int *p, unsigned int old,
 214         unsigned int new)
 215 {
 216         unsigned int prev;
 217
 218         __asm__ __volatile__ ("\n\
 219 1:      lwarx   %0,0,%2 \n\
 220         cmpw    0,%0,%3 \n\
 221         bne     2f \n"
 222         PPC405_ERR77(0,%2)
 223 "       stwcx.  %4,0,%2 \n\
 224         bne-    1b\n"
 225 "2:"
 226         : "=&r" (prev), "=m" (*p)
 227         : "r" (p), "r" (old), "r" (new), "m" (*p)
 228         : "cc", "memory");
 229
 230         return prev;
 231 }
 232
 233 /* This function doesn't exist, so you'll get a linker error
 234    if something tries to do an invalid cmpxchg().  */
 235 extern void __cmpxchg_called_with_bad_pointer(void);
 236
 237 static __inline__ unsigned long
 238 __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new,
 239         unsigned int size)
 240 {
 241         switch (size) {
 242         case 4:
 243                 return __cmpxchg_u32(ptr, old, new);
 244 #if 0   /* we don't have __cmpxchg_u64 on 32-bit PPC */
 245         case 8:
 246                 return __cmpxchg_u64(ptr, old, new);
 247 #endif /* 0 */
 248         }
 249         __cmpxchg_called_with_bad_pointer();
 250         return old;
 251 }
 252
 253 #define cmpxchg(ptr, o, n)                                               \
 254   ({                                                                     \
 255      __typeof__(*(ptr)) _o_ = (o);                                       \
 256      __typeof__(*(ptr)) _n_ = (n);                                       \
 257      (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,           \
 258                                     (unsigned long)_n_, sizeof(*(ptr))); \
 259   })
 260
 261 #include <asm-generic/cmpxchg-local.h>
 262
 263 static inline unsigned long __cmpxchg_local(volatile void *ptr,
 264                                       unsigned long old,
 265                                       unsigned long new, int size)
 266 {
 267         switch (size) {
 268         case 4:
 269                 return __cmpxchg_u32_local(ptr, old, new);
 270         default:
 271                 return __cmpxchg_local_generic(ptr, old, new, size);
 272         }
 273
 274         return old;
 275 }
 276
 277 /*
 278  * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
 279  * them available.
 280  */
 281 #define cmpxchg_local(ptr, o, n)                                        \
 282         ((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o), \
 283                         (unsigned long)(n), sizeof(*(ptr))))
 284 #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
 285
 286 #define arch_align_stack(x) (x)
 287
 288 #endif /* __KERNEL__ */
 289 #endif /* __PPC_SYSTEM_H */