include/asm-ppc/system.h

   1 /*
   2  * $Id: system.h,v 1.47 1999/08/22 12:31:08 paulus Exp $
   3  *
   4  * Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
   5  */
   6 #ifndef __PPC_SYSTEM_H
   7 #define __PPC_SYSTEM_H
   8
   9 #include <linux/kdev_t.h>
  10
  11 #include <asm/processor.h>
  12 #include <asm/atomic.h>
  13 #include <asm/irq_control.h>
  14
  15 /*
  16  * Memory barrier.
  17  * The sync instruction guarantees that all memory accesses initiated
  18  * by this processor have been performed (with respect to all other
  19  * mechanisms that access memory).  The eieio instruction is a barrier
  20  * providing an ordering (separately) for (a) cacheable stores and (b)
  21  * loads and stores to non-cacheable memory (e.g. I/O devices).
  22  *
  23  * mb() prevents loads and stores being reordered across this point.
  24  * rmb() prevents loads being reordered across this point.
  25  * wmb() prevents stores being reordered across this point.
  26  *
  27  * We can use the eieio instruction for wmb, but since it doesn't
  28  * give any ordering guarantees about loads, we have to use the
  29  * stronger but slower sync instruction for mb and rmb.
  30  */
  31 #define mb()  __asm__ __volatile__ ("sync" : : : "memory")
  32 #define rmb()  __asm__ __volatile__ ("sync" : : : "memory")
  33 #define wmb()  __asm__ __volatile__ ("eieio" : : : "memory")
  34
  35 extern void xmon_irq(int, void *, struct pt_regs *);
  36 extern void xmon(struct pt_regs *excp);
  37
  38
  39 /* Data cache block flush - write out the cache line containing the
  40    specified address and then invalidate it in the cache. */
  41 extern __inline__ void dcbf(void *line)
  42 {
  43         asm("dcbf %0,%1; sync" : : "r" (line), "r" (0));
  44 }
  45
  46 extern void print_backtrace(unsigned long *);
  47 extern void show_regs(struct pt_regs * regs);
  48 extern void flush_instruction_cache(void);
  49 extern void hard_reset_now(void);
  50 extern void poweroff_now(void);
  51 extern int _get_PVR(void);
  52 extern long _get_L2CR(void);
  53 extern void _set_L2CR(unsigned long);
  54 extern void via_cuda_init(void);
  55 extern void pmac_nvram_init(void);
  56 extern void read_rtc_time(void);
  57 extern void pmac_find_display(void);
  58 extern void giveup_fpu(struct task_struct *);
  59 extern void enable_kernel_fp(void);
  60 extern void cvt_fd(float *from, double *to, unsigned long *fpscr);
  61 extern void cvt_df(double *from, float *to, unsigned long *fpscr);
  62 extern int call_rtas(const char *, int, int, unsigned long *, ...);
  63
  64 struct device_node;
  65 extern void note_scsi_host(struct device_node *, void *);
  66
  67 struct task_struct;
  68 #define prepare_to_switch()     do { } while(0)
  69 #define switch_to(prev,next,last) _switch_to((prev),(next),&(last))
  70 extern void _switch_to(struct task_struct *, struct task_struct *,
  71                        struct task_struct **);
  72
  73 struct thread_struct;
  74 extern struct task_struct *_switch(struct thread_struct *prev,
  75                                    struct thread_struct *next);
  76
  77 extern unsigned int rtas_data;
  78
  79 struct pt_regs;
  80 extern void dump_regs(struct pt_regs *);
  81
  82 #ifndef __SMP__
  83
  84 #define cli()   __cli()
  85 #define sti()   __sti()
  86 #define save_flags(flags)       __save_flags(flags)
  87 #define restore_flags(flags)    __restore_flags(flags)
  88 #define save_and_cli(flags)     __save_and_cli(flags)
  89
  90 #else /* __SMP__ */
  91
  92 extern void __global_cli(void);
  93 extern void __global_sti(void);
  94 extern unsigned long __global_save_flags(void);
  95 extern void __global_restore_flags(unsigned long);
  96 #define cli() __global_cli()
  97 #define sti() __global_sti()
  98 #define save_flags(x) ((x)=__global_save_flags())
  99 #define restore_flags(x) __global_restore_flags(x)
 100
 101 #endif /* !__SMP__ */
 102
 103 #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
 104
 105 extern unsigned long xchg_u64(void *ptr, unsigned long val);
 106 extern unsigned long xchg_u32(void *ptr, unsigned long val);
 107
 108 /*
 109  * This function doesn't exist, so you'll get a linker error
 110  * if something tries to do an invalid xchg().
 111  *
 112  * This only works if the compiler isn't horribly bad at optimizing.
 113  * gcc-2.5.8 reportedly can't handle this, but as that doesn't work
 114  * too well on the alpha anyway..
 115  */
 116 extern void __xchg_called_with_bad_pointer(void);
 117
 118 #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
 119 #define tas(ptr) (xchg((ptr),1))
 120
 121 static inline unsigned long __xchg(unsigned long x, void * ptr, int size)
 122 {
 123         switch (size) {
 124         case 4:
 125                 return (unsigned long )xchg_u32(ptr, x);
 126         case 8:
 127                 return (unsigned long )xchg_u64(ptr, x);
 128         }
 129         __xchg_called_with_bad_pointer();
 130         return x;
 131
 132
 133 }
 134
 135 extern inline void * xchg_ptr(void * m, void * val)
 136 {
 137         return (void *) xchg_u32(m, (unsigned long) val);
 138 }
 139
 140 #endif