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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 | #ifndef _M68K_SYSTEM_H #define _M68K_SYSTEM_H #include <linux/config.h> /* get configuration macros */ #include <linux/linkage.h> #include <asm/segment.h> extern inline unsigned long rdusp(void) { unsigned long usp; __asm__ __volatile__("movec %/usp,%0" : "=d" (usp)); return usp; } extern inline void wrusp(unsigned long usp) { __asm__ __volatile__("movec %0,%/usp" : : "d" (usp)); } /* * switch_to(n) should switch tasks to task ptr, first checking that * ptr isn't the current task, in which case it does nothing. This * also clears the TS-flag if the task we switched to has used the * math co-processor latest. */ /* * switch_to() saves the extra registers, that are not saved * automatically by SAVE_SWITCH_STACK in resume(), ie. d0-d5 and * a0-a1. Some of these are used by schedule() and its predecessors * and so we might get see unexpected behaviors when a task returns * with unexpected register values. * * syscall stores these registers itself and none of them are used * by syscall after the function in the syscall has been called. * * Beware that resume now expects *next to be in d1 and the offset of * tss to be in a1. This saves a few instructions as we no longer have * to push them onto the stack and read them back right after. * * 02/17/96 - Jes Sorensen (jds@kom.auc.dk) * * Changed 96/09/19 by Andreas Schwab * pass prev in a0, next in a1, offset of tss in d1, and whether * the mm structures are shared in d2 (to avoid atc flushing). */ asmlinkage void resume(void); #define switch_to(prev,next) { \ register void *_prev __asm__ ("a0") = (prev); \ register void *_next __asm__ ("a1") = (next); \ register int _tssoff __asm__ ("d1") = (int)&((struct task_struct *)0)->tss; \ register char _shared __asm__ ("d2") = ((prev)->mm == (next)->mm); \ __asm__ __volatile__("jbsr " SYMBOL_NAME_STR(resume) "\n\t" \ : : "a" (_prev), "a" (_next), "d" (_tssoff), \ "d" (_shared) \ : "d0", "d1", "d2", "d3", "d4", "d5", "a0", "a1"); \ } #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr)))) #define tas(ptr) (xchg((ptr),1)) struct __xchg_dummy { unsigned long a[100]; }; #define __xg(x) ((volatile struct __xchg_dummy *)(x)) #if defined(CONFIG_ATARI) && !defined(CONFIG_AMIGA) && !defined(CONFIG_MAC) /* block out HSYNC on the atari */ #define sti() __asm__ __volatile__ ("andiw #0xfbff,%/sr": : : "memory") #else /* portable version */ #define sti() __asm__ __volatile__ ("andiw #0xf8ff,%/sr": : : "memory") #endif /* machine compilation types */ #define cli() __asm__ __volatile__ ("oriw #0x0700,%/sr": : : "memory") #define nop() __asm__ __volatile__ ("nop"::) #define mb() __asm__ __volatile__ ("" : : :"memory") #define save_flags(x) \ __asm__ __volatile__("movew %/sr,%0":"=d" (x) : /* no input */ :"memory") #define restore_flags(x) \ __asm__ __volatile__("movew %0,%/sr": /* no outputs */ :"d" (x) : "memory") #define iret() __asm__ __volatile__ ("rte": : :"memory", "sp", "cc") #ifndef CONFIG_RMW_INSNS static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) { unsigned long tmp, flags; save_flags(flags); cli(); switch (size) { case 1: __asm__ __volatile__ ("moveb %2,%0\n\t" "moveb %1,%2" : "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory"); break; case 2: __asm__ __volatile__ ("movew %2,%0\n\t" "movew %1,%2" : "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory"); break; case 4: __asm__ __volatile__ ("movel %2,%0\n\t" "movel %1,%2" : "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory"); break; } restore_flags(flags); return tmp; } #else static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) { switch (size) { case 1: __asm__ __volatile__ ("moveb %2,%0\n\t" "1:\n\t" "casb %0,%1,%2\n\t" "jne 1b" : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); break; case 2: __asm__ __volatile__ ("movew %2,%0\n\t" "1:\n\t" "casw %0,%1,%2\n\t" "jne 1b" : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); break; case 4: __asm__ __volatile__ ("movel %2,%0\n\t" "1:\n\t" "casl %0,%1,%2\n\t" "jne 1b" : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); break; } return x; } #endif #endif /* _M68K_SYSTEM_H */ |