#ifndef __ASM_SYSTEM_H #define __ASM_SYSTEM_H #include #include #include #include #include /* for LOCK_PREFIX */ #ifdef __KERNEL__ struct task_struct; /* one of the stranger aspects of C forward declarations.. */ extern void FASTCALL(__switch_to(struct task_struct *prev, struct task_struct *next)); #define prepare_to_switch() do { } while(0) #define switch_to(prev,next,last) do { \ asm volatile("pushl %%esi\n\t" \ "pushl %%edi\n\t" \ "pushl %%ebp\n\t" \ "movl %%esp,%0\n\t" /* save ESP */ \ "movl %3,%%esp\n\t" /* restore ESP */ \ "movl $1f,%1\n\t" /* save EIP */ \ "pushl %4\n\t" /* restore EIP */ \ "jmp __switch_to\n" \ "1:\t" \ "popl %%ebp\n\t" \ "popl %%edi\n\t" \ "popl %%esi\n\t" \ :"=m" (prev->thread.esp),"=m" (prev->thread.eip), \ "=b" (last) \ :"m" (next->thread.esp),"m" (next->thread.eip), \ "a" (prev), "d" (next), \ "b" (prev)); \ } while (0) #define _set_base(addr,base) do { unsigned long __pr; \ __asm__ __volatile__ ("movw %%dx,%1\n\t" \ "rorl $16,%%edx\n\t" \ "movb %%dl,%2\n\t" \ "movb %%dh,%3" \ :"=&d" (__pr) \ :"m" (*((addr)+2)), \ "m" (*((addr)+4)), \ "m" (*((addr)+7)), \ "0" (base) \ ); } while(0) #define _set_limit(addr,limit) do { unsigned long __lr; \ __asm__ __volatile__ ("movw %%dx,%1\n\t" \ "rorl $16,%%edx\n\t" \ "movb %2,%%dh\n\t" \ "andb $0xf0,%%dh\n\t" \ "orb %%dh,%%dl\n\t" \ "movb %%dl,%2" \ :"=&d" (__lr) \ :"m" (*(addr)), \ "m" (*((addr)+6)), \ "0" (limit) \ ); } while(0) #define set_base(ldt,base) _set_base( ((char *)&(ldt)) , (base) ) #define set_limit(ldt,limit) _set_limit( ((char *)&(ldt)) , ((limit)-1)>>12 ) static inline unsigned long _get_base(char * addr) { unsigned long __base; __asm__("movb %3,%%dh\n\t" "movb %2,%%dl\n\t" "shll $16,%%edx\n\t" "movw %1,%%dx" :"=&d" (__base) :"m" (*((addr)+2)), "m" (*((addr)+4)), "m" (*((addr)+7))); return __base; } #define get_base(ldt) _get_base( ((char *)&(ldt)) ) /* * Load a segment. Fall back on loading the zero * segment if something goes wrong.. */ #define loadsegment(seg,value) \ asm volatile("\n" \ "1:\t" \ "mov %0,%%" #seg "\n" \ "2:\n" \ ".section .fixup,\"ax\"\n" \ "3:\t" \ "pushl $0\n\t" \ "popl %%" #seg "\n\t" \ "jmp 2b\n" \ ".previous\n" \ ".section __ex_table,\"a\"\n\t" \ ".align 4\n\t" \ ".long 1b,3b\n" \ ".previous" \ : :"m" (value)) /* * Clear and set 'TS' bit respectively */ #define clts() __asm__ __volatile__ ("clts") #define read_cr0() ({ \ unsigned int __dummy; \ __asm__( \ "movl %%cr0,%0\n\t" \ :"=r" (__dummy)); \ __dummy; \ }) #define write_cr0(x) \ __asm__("movl %0,%%cr0": :"r" (x)); #define read_cr4() ({ \ unsigned int __dummy; \ __asm__( \ "movl %%cr4,%0\n\t" \ :"=r" (__dummy)); \ __dummy; \ }) #define write_cr4(x) \ __asm__("movl %0,%%cr4": :"r" (x)); #define stts() write_cr0(8 | read_cr0()) #endif /* __KERNEL__ */ #define wbinvd() \ __asm__ __volatile__ ("wbinvd": : :"memory"); static inline unsigned long get_limit(unsigned long segment) { unsigned long __limit; __asm__("lsll %1,%0" :"=r" (__limit):"r" (segment)); return __limit+1; } #define nop() __asm__ __volatile__ ("nop") #define xchg(ptr,v) ((__typeof__(*(ptr)))__xchg((unsigned long)(v),(ptr),sizeof(*(ptr)))) #define tas(ptr) (xchg((ptr),1)) struct __xchg_dummy { unsigned long a[100]; }; #define __xg(x) ((struct __xchg_dummy *)(x)) /* * The semantics of XCHGCMP8B are a bit strange, this is why * there is a loop and the loading of %%eax and %%edx has to * be inside. This inlines well in most cases, the cached * cost is around ~38 cycles. (in the future we might want * to do an SIMD/3DNOW!/MMX/FPU 64-bit store here, but that * might have an implicit FPU-save as a cost, so it's not * clear which path to go.) * * chmxchg8b must be used with the lock prefix here to allow * the instruction to be executed atomically, see page 3-102 * of the instruction set reference 24319102.pdf. We need * the reader side to see the coherent 64bit value. */ static inline void __set_64bit (unsigned long long * ptr, unsigned int low, unsigned int high) { __asm__ __volatile__ ( "\n1:\t" "movl (%0), %%eax\n\t" "movl 4(%0), %%edx\n\t" "lock cmpxchg8b (%0)\n\t" "jnz 1b" : /* no outputs */ : "D"(ptr), "b"(low), "c"(high) : "ax","dx","memory"); } static inline void __set_64bit_constant (unsigned long long *ptr, unsigned long long value) { __set_64bit(ptr,(unsigned int)(value), (unsigned int)((value)>>32ULL)); } #define ll_low(x) *(((unsigned int*)&(x))+0) #define ll_high(x) *(((unsigned int*)&(x))+1) static inline void __set_64bit_var (unsigned long long *ptr, unsigned long long value) { __set_64bit(ptr,ll_low(value), ll_high(value)); } #define set_64bit(ptr,value) \ (__builtin_constant_p(value) ? \ __set_64bit_constant(ptr, value) : \ __set_64bit_var(ptr, value) ) #define _set_64bit(ptr,value) \ (__builtin_constant_p(value) ? \ __set_64bit(ptr, (unsigned int)(value), (unsigned int)((value)>>32ULL) ) : \ __set_64bit(ptr, ll_low(value), ll_high(value)) ) /* * Note: no "lock" prefix even on SMP: xchg always implies lock anyway * Note 2: xchg has side effect, so that attribute volatile is necessary, * but generally the primitive is invalid, *ptr is output argument. --ANK */ static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) { switch (size) { case 1: __asm__ __volatile__("xchgb %b0,%1" :"=q" (x) :"m" (*__xg(ptr)), "0" (x) :"memory"); break; case 2: __asm__ __volatile__("xchgw %w0,%1" :"=r" (x) :"m" (*__xg(ptr)), "0" (x) :"memory"); break; case 4: __asm__ __volatile__("xchgl %0,%1" :"=r" (x) :"m" (*__xg(ptr)), "0" (x) :"memory"); break; } return x; } /* * Atomic compare and exchange. Compare OLD with MEM, if identical, * store NEW in MEM. Return the initial value in MEM. Success is * indicated by comparing RETURN with OLD. */ #ifdef CONFIG_X86_CMPXCHG #define __HAVE_ARCH_CMPXCHG 1 #endif static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size) { unsigned long prev; switch (size) { case 1: __asm__ __volatile__(LOCK_PREFIX "cmpxchgb %b1,%2" : "=a"(prev) : "q"(new), "m"(*__xg(ptr)), "0"(old) : "memory"); return prev; case 2: __asm__ __volatile__(LOCK_PREFIX "cmpxchgw %w1,%2" : "=a"(prev) : "q"(new), "m"(*__xg(ptr)), "0"(old) : "memory"); return prev; case 4: __asm__ __volatile__(LOCK_PREFIX "cmpxchgl %1,%2" : "=a"(prev) : "q"(new), "m"(*__xg(ptr)), "0"(old) : "memory"); return prev; } return old; } #define cmpxchg(ptr,o,n)\ ((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\ (unsigned long)(n),sizeof(*(ptr)))) /* * Force strict CPU ordering. * And yes, this is required on UP too when we're talking * to devices. * * For now, "wmb()" doesn't actually do anything, as all * Intel CPU's follow what Intel calls a *Processor Order*, * in which all writes are seen in the program order even * outside the CPU. * * I expect future Intel CPU's to have a weaker ordering, * but I'd also expect them to finally get their act together * and add some real memory barriers if so. * * Some non intel clones support out of order store. wmb() ceases to be a * nop for these. */ #define mb() __asm__ __volatile__ ("lock; addl $0,0(%%esp)": : :"memory") #define rmb() mb() #ifdef CONFIG_X86_OOSTORE #define wmb() __asm__ __volatile__ ("lock; addl $0,0(%%esp)": : :"memory") #else #define wmb() __asm__ __volatile__ ("": : :"memory") #endif #ifdef CONFIG_SMP #define smp_mb() mb() #define smp_rmb() rmb() #define smp_wmb() wmb() #define set_mb(var, value) do { (void) xchg(&var, value); } while (0) #else #define smp_mb() barrier() #define smp_rmb() barrier() #define smp_wmb() barrier() #define set_mb(var, value) do { var = value; barrier(); } while (0) #endif #define set_wmb(var, value) do { var = value; wmb(); } while (0) /* interrupt control.. */ #define __save_flags(x) __asm__ __volatile__("pushfl ; popl %0":"=g" (x): /* no input */) #define __restore_flags(x) __asm__ __volatile__("pushl %0 ; popfl": /* no output */ :"g" (x):"memory", "cc") #define __cli() __asm__ __volatile__("cli": : :"memory") #define __sti() __asm__ __volatile__("sti": : :"memory") /* used in the idle loop; sti takes one instruction cycle to complete */ #define safe_halt() __asm__ __volatile__("sti; hlt": : :"memory") #define __save_and_cli(x) do { __save_flags(x); __cli(); } while(0); #define __save_and_sti(x) do { __save_flags(x); __sti(); } while(0); /* For spinlocks etc */ #if 0 #define local_irq_save(x) __asm__ __volatile__("pushfl ; popl %0 ; cli":"=g" (x): /* no input */ :"memory") #define local_irq_set(x) __asm__ __volatile__("pushfl ; popl %0 ; sti":"=g" (x): /* no input */ :"memory") #else #define local_irq_save(x) __save_and_cli(x) #define local_irq_set(x) __save_and_sti(x) #endif #define local_irq_restore(x) __restore_flags(x) #define local_irq_disable() __cli() #define local_irq_enable() __sti() #ifdef CONFIG_SMP extern void __global_cli(void); extern void __global_sti(void); extern unsigned long __global_save_flags(void); extern void __global_restore_flags(unsigned long); #define cli() __global_cli() #define sti() __global_sti() #define save_flags(x) ((x)=__global_save_flags()) #define restore_flags(x) __global_restore_flags(x) #define save_and_cli(x) do { save_flags(x); cli(); } while(0); #define save_and_sti(x) do { save_flags(x); sti(); } while(0); #else #define cli() __cli() #define sti() __sti() #define save_flags(x) __save_flags(x) #define restore_flags(x) __restore_flags(x) #define save_and_cli(x) __save_and_cli(x) #define save_and_sti(x) __save_and_sti(x) #endif /* * disable hlt during certain critical i/o operations */ #define HAVE_DISABLE_HLT void disable_hlt(void); void enable_hlt(void); extern unsigned long dmi_broken; extern int is_sony_vaio_laptop; #define BROKEN_ACPI_Sx 0x0001 #define BROKEN_INIT_AFTER_S1 0x0002 #define BROKEN_PNP_BIOS 0x0004 #endif