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#ifndef __ASM_SYSTEM_H
#define __ASM_SYSTEM_H
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <asm/segment.h>
#include <linux/bitops.h> /* 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" \
"movl %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" (*(unsigned int *)&(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.)
*/
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"
"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
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))))
#else
/* Compiling for a 386 proper. Is it worth implementing via cli/sti? */
#endif
/*
* 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()
#else
#define smp_mb() barrier()
#define smp_rmb() barrier()
#define smp_wmb() barrier()
#endif
#define set_mb(var, value) do { xchg(&var, value); } while (0)
#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")
/* For spinlocks etc */
#define local_irq_save(x) __asm__ __volatile__("pushfl ; popl %0 ; cli":"=g" (x): /* no input */ :"memory")
#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)
#else
#define cli() __cli()
#define sti() __sti()
#define save_flags(x) __save_flags(x)
#define restore_flags(x) __restore_flags(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
#endif
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