system.h

来自「Linux Kernel 2.6.9 for OMAP1710」· C头文件 代码 · 共 625 行 · 第 1/2 页

#define local_irq_save(flags)	do { (flags) = swpipl(IPL_MAX); barrier(); } while(0)
#define local_irq_restore(flags)	do { barrier(); setipl(flags); barrier(); } while(0)

#define irqs_disabled()	(getipl() == IPL_MAX)

/*
 * TB routines..
 */
#define __tbi(nr,arg,arg1...)					\
({								\
	register unsigned long __r16 __asm__("$16") = (nr);	\
	register unsigned long __r17 __asm__("$17"); arg;	\
	__asm__ __volatile__(					\
		"call_pal %3 #__tbi"				\
		:"=r" (__r16),"=r" (__r17)			\
		:"0" (__r16),"i" (PAL_tbi) ,##arg1		\
		:"$0", "$1", "$22", "$23", "$24", "$25");	\
})

#define tbi(x,y)	__tbi(x,__r17=(y),"1" (__r17))
#define tbisi(x)	__tbi(1,__r17=(x),"1" (__r17))
#define tbisd(x)	__tbi(2,__r17=(x),"1" (__r17))
#define tbis(x)		__tbi(3,__r17=(x),"1" (__r17))
#define tbiap()		__tbi(-1, /* no second argument */)
#define tbia()		__tbi(-2, /* no second argument */)

/*
 * Atomic exchange.
 * Since it can be used to implement critical sections
 * it must clobber "memory" (also for interrupts in UP).
 */

static inline unsigned long
__xchg_u8(volatile char *m, unsigned long val)
{
	unsigned long ret, tmp, addr64;

	__asm__ __volatile__(
	"	andnot	%4,7,%3\n"
	"	insbl	%1,%4,%1\n"
	"1:	ldq_l	%2,0(%3)\n"
	"	extbl	%2,%4,%0\n"
	"	mskbl	%2,%4,%2\n"
	"	or	%1,%2,%2\n"
	"	stq_c	%2,0(%3)\n"
	"	beq	%2,2f\n"
#ifdef CONFIG_SMP
	"	mb\n"
#endif
	".subsection 2\n"
	"2:	br	1b\n"
	".previous"
	: "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64)
	: "r" ((long)m), "1" (val) : "memory");

	return ret;
}

static inline unsigned long
__xchg_u16(volatile short *m, unsigned long val)
{
	unsigned long ret, tmp, addr64;

	__asm__ __volatile__(
	"	andnot	%4,7,%3\n"
	"	inswl	%1,%4,%1\n"
	"1:	ldq_l	%2,0(%3)\n"
	"	extwl	%2,%4,%0\n"
	"	mskwl	%2,%4,%2\n"
	"	or	%1,%2,%2\n"
	"	stq_c	%2,0(%3)\n"
	"	beq	%2,2f\n"
#ifdef CONFIG_SMP
	"	mb\n"
#endif
	".subsection 2\n"
	"2:	br	1b\n"
	".previous"
	: "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64)
	: "r" ((long)m), "1" (val) : "memory");

	return ret;
}

static inline unsigned long
__xchg_u32(volatile int *m, unsigned long val)
{
	unsigned long dummy;

	__asm__ __volatile__(
	"1:	ldl_l %0,%4\n"
	"	bis $31,%3,%1\n"
	"	stl_c %1,%2\n"
	"	beq %1,2f\n"
#ifdef CONFIG_SMP
	"	mb\n"
#endif
	".subsection 2\n"
	"2:	br 1b\n"
	".previous"
	: "=&r" (val), "=&r" (dummy), "=m" (*m)
	: "rI" (val), "m" (*m) : "memory");

	return val;
}

static inline unsigned long
__xchg_u64(volatile long *m, unsigned long val)
{
	unsigned long dummy;

	__asm__ __volatile__(
	"1:	ldq_l %0,%4\n"
	"	bis $31,%3,%1\n"
	"	stq_c %1,%2\n"
	"	beq %1,2f\n"
#ifdef CONFIG_SMP
	"	mb\n"
#endif
	".subsection 2\n"
	"2:	br 1b\n"
	".previous"
	: "=&r" (val), "=&r" (dummy), "=m" (*m)
	: "rI" (val), "m" (*m) : "memory");

	return val;
}

/* This function doesn't exist, so you'll get a linker error
   if something tries to do an invalid xchg().  */
extern void __xchg_called_with_bad_pointer(void);

static inline unsigned long
__xchg(volatile void *ptr, unsigned long x, int size)
{
	switch (size) {
		case 1:
			return __xchg_u8(ptr, x);
		case 2:
			return __xchg_u16(ptr, x);
		case 4:
			return __xchg_u32(ptr, x);
		case 8:
			return __xchg_u64(ptr, x);
	}
	__xchg_called_with_bad_pointer();
	return x;
}

#define xchg(ptr,x)							     \
  ({									     \
     __typeof__(*(ptr)) _x_ = (x);					     \
     (__typeof__(*(ptr))) __xchg((ptr), (unsigned long)_x_, sizeof(*(ptr))); \
  })

#define tas(ptr) (xchg((ptr),1))


/* 
 * 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.
 *
 * The memory barrier should be placed in SMP only when we actually
 * make the change. If we don't change anything (so if the returned
 * prev is equal to old) then we aren't acquiring anything new and
 * we don't need any memory barrier as far I can tell.
 */

#define __HAVE_ARCH_CMPXCHG 1

static inline unsigned long
__cmpxchg_u8(volatile char *m, long old, long new)
{
	unsigned long prev, tmp, cmp, addr64;

	__asm__ __volatile__(
	"	andnot	%5,7,%4\n"
	"	insbl	%1,%5,%1\n"
	"1:	ldq_l	%2,0(%4)\n"
	"	extbl	%2,%5,%0\n"
	"	cmpeq	%0,%6,%3\n"
	"	beq	%3,2f\n"
	"	mskbl	%2,%5,%2\n"
	"	or	%1,%2,%2\n"
	"	stq_c	%2,0(%4)\n"
	"	beq	%2,3f\n"
#ifdef CONFIG_SMP
	"	mb\n"
#endif
	"2:\n"
	".subsection 2\n"
	"3:	br	1b\n"
	".previous"
	: "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64)
	: "r" ((long)m), "Ir" (old), "1" (new) : "memory");

	return prev;
}

static inline unsigned long
__cmpxchg_u16(volatile short *m, long old, long new)
{
	unsigned long prev, tmp, cmp, addr64;

	__asm__ __volatile__(
	"	andnot	%5,7,%4\n"
	"	inswl	%1,%5,%1\n"
	"1:	ldq_l	%2,0(%4)\n"
	"	extwl	%2,%5,%0\n"
	"	cmpeq	%0,%6,%3\n"
	"	beq	%3,2f\n"
	"	mskwl	%2,%5,%2\n"
	"	or	%1,%2,%2\n"
	"	stq_c	%2,0(%4)\n"
	"	beq	%2,3f\n"
#ifdef CONFIG_SMP
	"	mb\n"
#endif
	"2:\n"
	".subsection 2\n"
	"3:	br	1b\n"
	".previous"
	: "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64)
	: "r" ((long)m), "Ir" (old), "1" (new) : "memory");

	return prev;
}

static inline unsigned long
__cmpxchg_u32(volatile int *m, int old, int new)
{
	unsigned long prev, cmp;

	__asm__ __volatile__(
	"1:	ldl_l %0,%5\n"
	"	cmpeq %0,%3,%1\n"
	"	beq %1,2f\n"
	"	mov %4,%1\n"
	"	stl_c %1,%2\n"
	"	beq %1,3f\n"
#ifdef CONFIG_SMP
	"	mb\n"
#endif
	"2:\n"
	".subsection 2\n"
	"3:	br 1b\n"
	".previous"
	: "=&r"(prev), "=&r"(cmp), "=m"(*m)
	: "r"((long) old), "r"(new), "m"(*m) : "memory");

	return prev;
}

static inline unsigned long
__cmpxchg_u64(volatile long *m, unsigned long old, unsigned long new)
{
	unsigned long prev, cmp;

	__asm__ __volatile__(
	"1:	ldq_l %0,%5\n"
	"	cmpeq %0,%3,%1\n"
	"	beq %1,2f\n"
	"	mov %4,%1\n"
	"	stq_c %1,%2\n"
	"	beq %1,3f\n"
#ifdef CONFIG_SMP
	"	mb\n"
#endif
	"2:\n"
	".subsection 2\n"
	"3:	br 1b\n"
	".previous"
	: "=&r"(prev), "=&r"(cmp), "=m"(*m)
	: "r"((long) old), "r"(new), "m"(*m) : "memory");

	return prev;
}

/* This function doesn't exist, so you'll get a linker error
   if something tries to do an invalid cmpxchg().  */
extern void __cmpxchg_called_with_bad_pointer(void);

static inline unsigned long
__cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
{
	switch (size) {
		case 1:
			return __cmpxchg_u8(ptr, old, new);
		case 2:
			return __cmpxchg_u16(ptr, old, new);
		case 4:
			return __cmpxchg_u32(ptr, old, new);
		case 8:
			return __cmpxchg_u64(ptr, old, new);
	}
	__cmpxchg_called_with_bad_pointer();
	return old;
}

#define cmpxchg(ptr,o,n)						 \
  ({									 \
     __typeof__(*(ptr)) _o_ = (o);					 \
     __typeof__(*(ptr)) _n_ = (n);					 \
     (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,		 \
				    (unsigned long)_n_, sizeof(*(ptr))); \
  })

#endif /* __ASSEMBLY__ */

#endif