arch/ppc/include/asm/bitops.h - barebox/mindspeed - Git at Google

 /*
  * bitops.h: Bit string operations on the ppc
  */

 #ifndef _PPC_BITOPS_H
 #define _PPC_BITOPS_H

 #include <asm/byteorder.h>

 extern void set_bit(int nr, volatile void *addr);
 extern void clear_bit(int nr, volatile void *addr);
 extern void change_bit(int nr, volatile void *addr);
 extern int test_and_set_bit(int nr, volatile void *addr);
 extern int test_and_clear_bit(int nr, volatile void *addr);
 extern int test_and_change_bit(int nr, volatile void *addr);

 /*
  * Arguably these bit operations don't imply any memory barrier or
  * SMP ordering, but in fact a lot of drivers expect them to imply
  * both, since they do on x86 cpus.
  */
 #ifdef CONFIG_SMP
 #define SMP_WMB		"eieio\n"
 #define SMP_MB		"\nsync"
 #else
 #define SMP_WMB
 #define SMP_MB
 #endif /* CONFIG_SMP */

 #define __INLINE_BITOPS	1

 #if __INLINE_BITOPS
 /*
  * These used to be if'd out here because using : "cc" as a constraint
  * resulted in errors from egcs.  Things may be OK with gcc-2.95.
  */
 extern __inline__ void set_bit(int nr, volatile void * addr)
 {
 	unsigned long old;
 	unsigned long mask = 1 << (nr & 0x1f);
 	unsigned long *p = ((unsigned long *)addr) + (nr >> 5);

 	__asm__ __volatile__(SMP_WMB "\
 1:	lwarx	%0,0,%3\n\
 	or	%0,%0,%2\n\
 	stwcx.	%0,0,%3\n\
 	bne	1b"
 	SMP_MB
 	: "=&r" (old), "=m" (*p)
 	: "r" (mask), "r" (p), "m" (*p)
 	: "cc" );
 }

 extern __inline__ void clear_bit(int nr, volatile void *addr)
 {
 	unsigned long old;
 	unsigned long mask = 1 << (nr & 0x1f);
 	unsigned long *p = ((unsigned long *)addr) + (nr >> 5);

 	__asm__ __volatile__(SMP_WMB "\
 1:	lwarx	%0,0,%3\n\
 	andc	%0,%0,%2\n\
 	stwcx.	%0,0,%3\n\
 	bne	1b"
 	SMP_MB
 	: "=&r" (old), "=m" (*p)
 	: "r" (mask), "r" (p), "m" (*p)
 	: "cc");
 }

 extern __inline__ void change_bit(int nr, volatile void *addr)
 {
 	unsigned long old;
 	unsigned long mask = 1 << (nr & 0x1f);
 	unsigned long *p = ((unsigned long *)addr) + (nr >> 5);

 	__asm__ __volatile__(SMP_WMB "\
 1:	lwarx	%0,0,%3\n\
 	xor	%0,%0,%2\n\
 	stwcx.	%0,0,%3\n\
 	bne	1b"
 	SMP_MB
 	: "=&r" (old), "=m" (*p)
 	: "r" (mask), "r" (p), "m" (*p)
 	: "cc");
 }

 extern __inline__ int test_and_set_bit(int nr, volatile void *addr)
 {
 	unsigned int old, t;
 	unsigned int mask = 1 << (nr & 0x1f);
 	volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);

 	__asm__ __volatile__(SMP_WMB "\
 1:	lwarx	%0,0,%4\n\
 	or	%1,%0,%3\n\
 	stwcx.	%1,0,%4\n\
 	bne	1b"
 	SMP_MB
 	: "=&r" (old), "=&r" (t), "=m" (*p)
 	: "r" (mask), "r" (p), "m" (*p)
 	: "cc");

 	return (old & mask) != 0;
 }

 extern __inline__ int test_and_clear_bit(int nr, volatile void *addr)
 {
 	unsigned int old, t;
 	unsigned int mask = 1 << (nr & 0x1f);
 	volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);

 	__asm__ __volatile__(SMP_WMB "\
 1:	lwarx	%0,0,%4\n\
 	andc	%1,%0,%3\n\
 	stwcx.	%1,0,%4\n\
 	bne	1b"
 	SMP_MB
 	: "=&r" (old), "=&r" (t), "=m" (*p)
 	: "r" (mask), "r" (p), "m" (*p)
 	: "cc");

 	return (old & mask) != 0;
 }

 extern __inline__ int test_and_change_bit(int nr, volatile void *addr)
 {
 	unsigned int old, t;
 	unsigned int mask = 1 << (nr & 0x1f);
 	volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);

 	__asm__ __volatile__(SMP_WMB "\
 1:	lwarx	%0,0,%4\n\
 	xor	%1,%0,%3\n\
 	stwcx.	%1,0,%4\n\
 	bne	1b"
 	SMP_MB
 	: "=&r" (old), "=&r" (t), "=m" (*p)
 	: "r" (mask), "r" (p), "m" (*p)
 	: "cc");

 	return (old & mask) != 0;
 }
 #endif /* __INLINE_BITOPS */

 extern __inline__ int test_bit(int nr, __const__ volatile void *addr)
 {
 	__const__ unsigned int *p = (__const__ unsigned int *) addr;

 	return ((p[nr >> 5] >> (nr & 0x1f)) & 1) != 0;
 }

 /* Return the bit position of the most significant 1 bit in a word */
 extern __inline__ int __ilog2(unsigned int x)
 {
 	int lz;

 	asm ("cntlzw %0,%1" : "=r" (lz) : "r" (x));
 	return 31 - lz;
 }

 extern __inline__ int ffz(unsigned int x)
 {
 	if ((x = ~x) == 0)
 		return 32;
 	return __ilog2(x & -x);
 }

 #ifdef __KERNEL__

 /*
  * ffs: find first bit set. This is defined the same way as
  * the libc and compiler builtin ffs routines, therefore
  * differs in spirit from the above ffz (man ffs).
  */
 extern __inline__ int ffs(int x)
 {
 	return __ilog2(x & -x) + 1;
 }

 #include <asm-generic/bitops/hweight.h>

 #endif /* __KERNEL__ */

 /*
  * This implementation of find_{first,next}_zero_bit was stolen from
  * Linus' asm-alpha/bitops.h.
  */
 #define find_first_zero_bit(addr, size) \
 	find_next_zero_bit((addr), (size), 0)

 extern __inline__ unsigned long find_next_zero_bit(void * addr,
 	unsigned long size, unsigned long offset)
 {
 	unsigned int * p = ((unsigned int *) addr) + (offset >> 5);
 	unsigned int result = offset & ~31UL;
 	unsigned int tmp;

 	if (offset >= size)
 		return size;
 	size -= result;
 	offset &= 31UL;
 	if (offset) {
 		tmp = *p++;
 		tmp |= ~0UL >> (32-offset);
 		if (size < 32)
 			goto found_first;
 		if (tmp != ~0U)
 			goto found_middle;
 		size -= 32;
 		result += 32;
 	}
 	while (size >= 32) {
 		if ((tmp = *p++) != ~0U)
 			goto found_middle;
 		result += 32;
 		size -= 32;
 	}
 	if (!size)
 		return result;
 	tmp = *p;
 found_first:
 	tmp |= ~0UL << size;
 found_middle:
 	return result + ffz(tmp);
 }


 #define _EXT2_HAVE_ASM_BITOPS_

 #ifdef __KERNEL__
 /*
  * test_and_{set,clear}_bit guarantee atomicity without
  * disabling interrupts.
  */
 #define ext2_set_bit(nr, addr)		test_and_set_bit((nr) ^ 0x18, addr)
 #define ext2_clear_bit(nr, addr)	test_and_clear_bit((nr) ^ 0x18, addr)

 #else
 extern __inline__ int ext2_set_bit(int nr, void * addr)
 {
 	int		mask;
 	unsigned char	*ADDR = (unsigned char *) addr;
 	int oldbit;

 	ADDR += nr >> 3;
 	mask = 1 << (nr & 0x07);
 	oldbit = (*ADDR & mask) ? 1 : 0;
 	*ADDR |= mask;
 	return oldbit;
 }

 extern __inline__ int ext2_clear_bit(int nr, void * addr)
 {
 	int		mask;
 	unsigned char	*ADDR = (unsigned char *) addr;
 	int oldbit;

 	ADDR += nr >> 3;
 	mask = 1 << (nr & 0x07);
 	oldbit = (*ADDR & mask) ? 1 : 0;
 	*ADDR = *ADDR & ~mask;
 	return oldbit;
 }
 #endif	/* __KERNEL__ */

 extern __inline__ int ext2_test_bit(int nr, __const__ void * addr)
 {
 	__const__ unsigned char	*ADDR = (__const__ unsigned char *) addr;

 	return (ADDR[nr >> 3] >> (nr & 7)) & 1;
 }

 /*
  * This implementation of ext2_find_{first,next}_zero_bit was stolen from
  * Linus' asm-alpha/bitops.h and modified for a big-endian machine.
  */

 #define ext2_find_first_zero_bit(addr, size) \
 	ext2_find_next_zero_bit((addr), (size), 0)

 #define ext2_find_next_zero_bit(addr, size, off) \
 	generic_find_next_zero_le_bit((unsigned long*)addr, size, off)

 /* Bitmap functions for the minix filesystem.  */
 #define minix_test_and_set_bit(nr,addr) ext2_set_bit(nr,addr)
 #define minix_set_bit(nr,addr) ((void)ext2_set_bit(nr,addr))
 #define minix_test_and_clear_bit(nr,addr) ext2_clear_bit(nr,addr)
 #define minix_test_bit(nr,addr) ext2_test_bit(nr,addr)
 #define minix_find_first_zero_bit(addr,size) ext2_find_first_zero_bit(addr,size)

 #endif /* _PPC_BITOPS_H */
	/*
	* bitops.h: Bit string operations on the ppc
	*/

	#ifndef _PPC_BITOPS_H
	#define _PPC_BITOPS_H

	#include <asm/byteorder.h>

	extern void set_bit(int nr, volatile void *addr);
	extern void clear_bit(int nr, volatile void *addr);
	extern void change_bit(int nr, volatile void *addr);
	extern int test_and_set_bit(int nr, volatile void *addr);
	extern int test_and_clear_bit(int nr, volatile void *addr);
	extern int test_and_change_bit(int nr, volatile void *addr);

	/*
	* Arguably these bit operations don't imply any memory barrier or
	* SMP ordering, but in fact a lot of drivers expect them to imply
	* both, since they do on x86 cpus.
	*/
	#ifdef CONFIG_SMP
	#define SMP_WMB "eieio\n"
	#define SMP_MB "\nsync"
	#else
	#define SMP_WMB
	#define SMP_MB
	#endif /* CONFIG_SMP */

	#define __INLINE_BITOPS 1

	#if __INLINE_BITOPS
	/*
	* These used to be if'd out here because using : "cc" as a constraint
	* resulted in errors from egcs. Things may be OK with gcc-2.95.
	*/
	extern __inline__ void set_bit(int nr, volatile void * addr)
	{
	unsigned long old;
	unsigned long mask = 1 << (nr & 0x1f);
	unsigned long p = ((unsigned long )addr) + (nr >> 5);

	__asm__ __volatile__(SMP_WMB "\
	1: lwarx %0,0,%3\n\
	or %0,%0,%2\n\
	stwcx. %0,0,%3\n\
	bne 1b"
	SMP_MB
	: "=&r" (old), "=m" (*p)
	: "r" (mask), "r" (p), "m" (*p)
	: "cc" );
	}

	extern __inline__ void clear_bit(int nr, volatile void *addr)
	{
	unsigned long old;
	unsigned long mask = 1 << (nr & 0x1f);
	unsigned long p = ((unsigned long )addr) + (nr >> 5);

	__asm__ __volatile__(SMP_WMB "\
	1: lwarx %0,0,%3\n\
	andc %0,%0,%2\n\
	stwcx. %0,0,%3\n\
	bne 1b"
	SMP_MB
	: "=&r" (old), "=m" (*p)
	: "r" (mask), "r" (p), "m" (*p)
	: "cc");
	}

	extern __inline__ void change_bit(int nr, volatile void *addr)
	{
	unsigned long old;
	unsigned long mask = 1 << (nr & 0x1f);
	unsigned long p = ((unsigned long )addr) + (nr >> 5);

	__asm__ __volatile__(SMP_WMB "\
	1: lwarx %0,0,%3\n\
	xor %0,%0,%2\n\
	stwcx. %0,0,%3\n\
	bne 1b"
	SMP_MB
	: "=&r" (old), "=m" (*p)
	: "r" (mask), "r" (p), "m" (*p)
	: "cc");
	}

	extern __inline__ int test_and_set_bit(int nr, volatile void *addr)
	{
	unsigned int old, t;
	unsigned int mask = 1 << (nr & 0x1f);
	volatile unsigned int p = ((volatile unsigned int )addr) + (nr >> 5);

	__asm__ __volatile__(SMP_WMB "\
	1: lwarx %0,0,%4\n\
	or %1,%0,%3\n\
	stwcx. %1,0,%4\n\
	bne 1b"
	SMP_MB
	: "=&r" (old), "=&r" (t), "=m" (*p)
	: "r" (mask), "r" (p), "m" (*p)
	: "cc");

	return (old & mask) != 0;
	}

	extern __inline__ int test_and_clear_bit(int nr, volatile void *addr)
	{
	unsigned int old, t;
	unsigned int mask = 1 << (nr & 0x1f);
	volatile unsigned int p = ((volatile unsigned int )addr) + (nr >> 5);

	__asm__ __volatile__(SMP_WMB "\
	1: lwarx %0,0,%4\n\
	andc %1,%0,%3\n\
	stwcx. %1,0,%4\n\
	bne 1b"
	SMP_MB
	: "=&r" (old), "=&r" (t), "=m" (*p)
	: "r" (mask), "r" (p), "m" (*p)
	: "cc");

	return (old & mask) != 0;
	}

	extern __inline__ int test_and_change_bit(int nr, volatile void *addr)
	{
	unsigned int old, t;
	unsigned int mask = 1 << (nr & 0x1f);
	volatile unsigned int p = ((volatile unsigned int )addr) + (nr >> 5);

	__asm__ __volatile__(SMP_WMB "\
	1: lwarx %0,0,%4\n\
	xor %1,%0,%3\n\
	stwcx. %1,0,%4\n\
	bne 1b"
	SMP_MB
	: "=&r" (old), "=&r" (t), "=m" (*p)
	: "r" (mask), "r" (p), "m" (*p)
	: "cc");

	return (old & mask) != 0;
	}
	#endif /* __INLINE_BITOPS */

	extern __inline__ int test_bit(int nr, __const__ volatile void *addr)
	{
	__const__ unsigned int p = (__const__ unsigned int ) addr;

	return ((p[nr >> 5] >> (nr & 0x1f)) & 1) != 0;
	}

	/* Return the bit position of the most significant 1 bit in a word */
	extern __inline__ int __ilog2(unsigned int x)
	{
	int lz;

	asm ("cntlzw %0,%1" : "=r" (lz) : "r" (x));
	return 31 - lz;
	}

	extern __inline__ int ffz(unsigned int x)
	{
	if ((x = ~x) == 0)
	return 32;
	return __ilog2(x & -x);
	}

	#ifdef __KERNEL__

	/*
	* ffs: find first bit set. This is defined the same way as
	* the libc and compiler builtin ffs routines, therefore
	* differs in spirit from the above ffz (man ffs).
	*/
	extern __inline__ int ffs(int x)
	{
	return __ilog2(x & -x) + 1;
	}

	#include <asm-generic/bitops/hweight.h>

	#endif /* __KERNEL__ */

	/*
	* This implementation of find_{first,next}_zero_bit was stolen from
	* Linus' asm-alpha/bitops.h.
	*/
	#define find_first_zero_bit(addr, size) \
	find_next_zero_bit((addr), (size), 0)

	extern __inline__ unsigned long find_next_zero_bit(void * addr,
	unsigned long size, unsigned long offset)
	{
	unsigned int * p = ((unsigned int *) addr) + (offset >> 5);
	unsigned int result = offset & ~31UL;
	unsigned int tmp;

	if (offset >= size)
	return size;
	size -= result;
	offset &= 31UL;
	if (offset) {
	tmp = *p++;
	tmp \|= ~0UL >> (32-offset);
	if (size < 32)
	goto found_first;
	if (tmp != ~0U)
	goto found_middle;
	size -= 32;
	result += 32;
	}
	while (size >= 32) {
	if ((tmp = *p++) != ~0U)
	goto found_middle;
	result += 32;
	size -= 32;
	}
	if (!size)
	return result;
	tmp = *p;
	found_first:
	tmp \|= ~0UL << size;
	found_middle:
	return result + ffz(tmp);
	}


	#define _EXT2_HAVE_ASM_BITOPS_

	#ifdef __KERNEL__
	/*
	* test_and_{set,clear}_bit guarantee atomicity without
	* disabling interrupts.
	*/
	#define ext2_set_bit(nr, addr) test_and_set_bit((nr) ^ 0x18, addr)
	#define ext2_clear_bit(nr, addr) test_and_clear_bit((nr) ^ 0x18, addr)

	#else
	extern __inline__ int ext2_set_bit(int nr, void * addr)
	{
	int mask;
	unsigned char ADDR = (unsigned char ) addr;
	int oldbit;

	ADDR += nr >> 3;
	mask = 1 << (nr & 0x07);
	oldbit = (*ADDR & mask) ? 1 : 0;
	*ADDR \|= mask;
	return oldbit;
	}

	extern __inline__ int ext2_clear_bit(int nr, void * addr)
	{
	int mask;
	unsigned char ADDR = (unsigned char ) addr;
	int oldbit;

	ADDR += nr >> 3;
	mask = 1 << (nr & 0x07);
	oldbit = (*ADDR & mask) ? 1 : 0;
	ADDR = ADDR & ~mask;
	return oldbit;
	}
	#endif /* __KERNEL__ */

	extern __inline__ int ext2_test_bit(int nr, __const__ void * addr)
	{
	__const__ unsigned char ADDR = (__const__ unsigned char ) addr;

	return (ADDR[nr >> 3] >> (nr & 7)) & 1;
	}

	/*
	* This implementation of ext2_find_{first,next}_zero_bit was stolen from
	* Linus' asm-alpha/bitops.h and modified for a big-endian machine.
	*/

	#define ext2_find_first_zero_bit(addr, size) \
	ext2_find_next_zero_bit((addr), (size), 0)

	#define ext2_find_next_zero_bit(addr, size, off) \
	generic_find_next_zero_le_bit((unsigned long*)addr, size, off)

	/* Bitmap functions for the minix filesystem. */
	#define minix_test_and_set_bit(nr,addr) ext2_set_bit(nr,addr)
	#define minix_set_bit(nr,addr) ((void)ext2_set_bit(nr,addr))
	#define minix_test_and_clear_bit(nr,addr) ext2_clear_bit(nr,addr)
	#define minix_test_bit(nr,addr) ext2_test_bit(nr,addr)
	#define minix_find_first_zero_bit(addr,size) ext2_find_first_zero_bit(addr,size)

	#endif /* _PPC_BITOPS_H */