root/include/asm-alpha/system.h

/* */

INCLUDED FROM

DEFINITIONS

1. xchg_u32
2. xchg_u64
3. __xchg

   1 #ifndef __ALPHA_SYSTEM_H
   2 #define __ALPHA_SYSTEM_H
   3 
   4 #include <asm/pal.h>    /* for backwards compatibility... */
   5 
   6 /*
   7  * System defines.. Note that this is included both from .c and .S
   8  * files, so it does only defines, not any C code.
   9  */
  10 
  11 /*
  12  * We leave one page for the initial stack page, and one page for
  13  * the initial process structure. Also, the console eats 3 MB for
  14  * the initial bootloader (one of which we can reclaim later).
  15  * With a few other pages for various reasons, we'll use an initial
  16  * load address of 0xfffffc0000310000UL
  17  */
  18 #define BOOT_PCB        0x20000000
  19 #define BOOT_ADDR       0x20000000
  20 #define BOOT_SIZE       (16*1024)
  21 
  22 #define KERNEL_START    0xfffffc0000300000
  23 #define SWAPPER_PGD     0xfffffc0000300000
  24 #define INIT_STACK      0xfffffc0000302000
  25 #define EMPTY_PGT       0xfffffc0000304000
  26 #define EMPTY_PGE       0xfffffc0000308000
  27 #define ZERO_PGE        0xfffffc000030A000
  28 
  29 #define START_ADDR      0xfffffc0000310000
  30 #define START_SIZE      (2*1024*1024)
  31 
  32 #ifndef __ASSEMBLY__
  33 
  34 extern void wrent(void *, unsigned long);
  35 extern void wrkgp(unsigned long);
  36 extern void wrusp(unsigned long);
  37 extern unsigned long rdusp(void);
  38 extern unsigned long rdmces (void);
  39 extern void wrmces (unsigned long);
  40 
  41 #define halt() __asm__ __volatile__(".long 0");
  42 
  43 extern void alpha_switch_to(unsigned long pctxp);
  44 
  45 #define switch_to(p) do { \
  46         current = p; \
  47         alpha_switch_to((unsigned long) &(p)->tss - 0xfffffc0000000000); \
  48 } while (0)
  49 
  50 #define mb() \
  51 __asm__ __volatile__("mb": : :"memory")
  52 
  53 #define draina() \
  54 __asm__ __volatile__ ("call_pal %0" : : "i" (PAL_draina) : "memory")
  55 
  56 #define getipl() \
  57 ({ unsigned long __old_ipl; \
  58 __asm__ __volatile__( \
  59         "call_pal 54\n\t" \
  60         "bis $0,$0,%0" \
  61         : "=r" (__old_ipl) \
  62         : : "$0", "$1", "$16", "$22", "$23", "$24", "$25"); \
  63 __old_ipl; })
  64 
  65 #define setipl(__new_ipl) \
  66 __asm__ __volatile__( \
  67         "bis %0,%0,$16\n\t" \
  68         "call_pal 53" \
  69         : : "r" (__new_ipl) \
  70         : "$0", "$1", "$16", "$22", "$23", "$24", "$25")
  71 
  72 #define swpipl(__new_ipl) \
  73 ({ unsigned long __old_ipl; \
  74 __asm__ __volatile__( \
  75         "bis %1,%1,$16\n\t" \
  76         "call_pal 53\n\t" \
  77         "bis $0,$0,%0" \
  78         : "=r" (__old_ipl) \
  79         : "r" (__new_ipl) \
  80         : "$0", "$1", "$16", "$22", "$23", "$24", "$25"); \
  81 __old_ipl; })
  82 
  83 #define cli()                   setipl(7)
  84 #define sti()                   setipl(0)
  85 #define save_flags(flags)       do { flags = getipl(); } while (0)
  86 #define restore_flags(flags)    setipl(flags)
  87 
  88 extern inline unsigned long xchg_u32(volatile int * m, unsigned long val)
     /*  */
  89 {
  90         unsigned long dummy, dummy2;
  91 
  92         __asm__ __volatile__(
  93                 "\n1:\t"
  94                 "ldl_l %0,%1\n\t"
  95                 "bis %2,%2,%3\n\t"
  96                 "stl_c %3,%1\n\t"
  97                 "beq %3,1b\n"
  98                 : "=r" (val), "=m" (*m), "=r" (dummy), "=r" (dummy2)
  99                 : "1" (*m), "2" (val));
 100         return val;
 101 }
 102 
 103 extern inline unsigned long xchg_u64(volatile long * m, unsigned long val)
     /*  */
 104 {
 105         unsigned long dummy, dummy2;
 106 
 107         __asm__ __volatile__(
 108                 "\n1:\t"
 109                 "ldq_l %0,%1\n\t"
 110                 "bis %2,%2,%3\n\t"
 111                 "stq_c %3,%1\n\t"
 112                 "beq %3,1b\n"
 113                 : "=r" (val), "=m" (*m), "=r" (dummy), "=r" (dummy2)
 114                 : "1" (*m), "2" (val));
 115         return val;
 116 }
 117 
 118 #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
 119 #define tas(ptr) (xchg((ptr),1))
 120 
 121 /*
 122  * This function doesn't exist, so you'll get a linker error
 123  * if something tries to do an invalid xchg().
 124  *
 125  * This only works if the compiler isn't horribly bad at optimizing.
 126  * gcc-2.5.8 reportedly can't handle this, but as that doesn't work
 127  * too well on the alpha anyway..
 128  */
 129 extern void __xchg_called_with_bad_pointer(void);
 130 
 131 static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size)
     /*  */
 132 {
 133         switch (size) {
 134                 case 4:
 135                         return xchg_u32(ptr, x);
 136                 case 8:
 137                         return xchg_u64(ptr, x);
 138         }
 139         __xchg_called_with_bad_pointer();
 140         return x;
 141 }
 142 
 143 #endif /* __ASSEMBLY__ */
 144 
 145 #endif

/* */