[J-u-boot.git] / include / linux / bitops.h

#ifndef _LINUX_BITOPS_H
#define _LINUX_BITOPS_H

#include <asm/types.h>

/*
 * 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).
 */

static inline int generic_ffs(int x)
{
	int r = 1;

	if (!x)
		return 0;
	if (!(x & 0xffff)) {
		x >>= 16;
		r += 16;
	}
	if (!(x & 0xff)) {
		x >>= 8;
		r += 8;
	}
	if (!(x & 0xf)) {
		x >>= 4;
		r += 4;
	}
	if (!(x & 3)) {
		x >>= 2;
		r += 2;
	}
	if (!(x & 1)) {
		x >>= 1;
		r += 1;
	}
	return r;
}

/**
 * fls - find last (most-significant) bit set
 * @x: the word to search
 *
 * This is defined the same way as ffs.
 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
 */
static inline int generic_fls(int x)
{
	int r = 32;

	if (!x)
		return 0;
	if (!(x & 0xffff0000u)) {
		x <<= 16;
		r -= 16;
	}
	if (!(x & 0xff000000u)) {
		x <<= 8;
		r -= 8;
	}
	if (!(x & 0xf0000000u)) {
		x <<= 4;
		r -= 4;
	}
	if (!(x & 0xc0000000u)) {
		x <<= 2;
		r -= 2;
	}
	if (!(x & 0x80000000u)) {
		x <<= 1;
		r -= 1;
	}
	return r;
}


/*
 * hweightN: returns the hamming weight (i.e. the number
 * of bits set) of a N-bit word
 */

static inline unsigned int generic_hweight32(unsigned int w)
{
	unsigned int res = (w & 0x55555555) + ((w >> 1) & 0x55555555);
	res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
	res = (res & 0x0F0F0F0F) + ((res >> 4) & 0x0F0F0F0F);
	res = (res & 0x00FF00FF) + ((res >> 8) & 0x00FF00FF);
	return (res & 0x0000FFFF) + ((res >> 16) & 0x0000FFFF);
}

static inline unsigned int generic_hweight16(unsigned int w)
{
	unsigned int res = (w & 0x5555) + ((w >> 1) & 0x5555);
	res = (res & 0x3333) + ((res >> 2) & 0x3333);
	res = (res & 0x0F0F) + ((res >> 4) & 0x0F0F);
	return (res & 0x00FF) + ((res >> 8) & 0x00FF);
}

static inline unsigned int generic_hweight8(unsigned int w)
{
	unsigned int res = (w & 0x55) + ((w >> 1) & 0x55);
	res = (res & 0x33) + ((res >> 2) & 0x33);
	return (res & 0x0F) + ((res >> 4) & 0x0F);
}

#define BIT_MASK(nr)		(1UL << ((nr) % BITS_PER_LONG))
#define BIT_WORD(nr)		((nr) / BITS_PER_LONG)

#include <asm/bitops.h>

/* linux/include/asm-generic/bitops/non-atomic.h */

#ifndef PLATFORM__SET_BIT
# define __set_bit generic_set_bit
#endif

#ifndef PLATFORM__CLEAR_BIT
# define __clear_bit generic_clear_bit
#endif

#ifndef PLATFORM_FFS
# define ffs generic_ffs
#endif

#ifndef PLATFORM_FLS
# define fls generic_fls
#endif

/**
 * __set_bit - Set a bit in memory
 * @nr: the bit to set
 * @addr: the address to start counting from
 *
 * Unlike set_bit(), this function is non-atomic and may be reordered.
 * If it's called on the same region of memory simultaneously, the effect
 * may be that only one operation succeeds.
 */
static inline void generic_set_bit(int nr, volatile unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);

	*p  |= mask;
}

static inline void generic_clear_bit(int nr, volatile unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);

	*p &= ~mask;
}

#endif
Commit	Line	Data
b15cbc0b WD	1	#ifndef _LINUX_BITOPS_H
	2	#define _LINUX_BITOPS_H
	3
02f99901	4	#include <asm/types.h>
b15cbc0b WD	5
	6	/*
	7	* ffs: find first bit set. This is defined the same way as
	8	* the libc and compiler builtin ffs routines, therefore
	9	* differs in spirit from the above ffz (man ffs).
	10	*/
	11
	12	static inline int generic_ffs(int x)
	13	{
	14	int r = 1;
	15
	16	if (!x)
	17	return 0;
	18	if (!(x & 0xffff)) {
	19	x >>= 16;
	20	r += 16;
	21	}
	22	if (!(x & 0xff)) {
	23	x >>= 8;
	24	r += 8;
	25	}
	26	if (!(x & 0xf)) {
	27	x >>= 4;
	28	r += 4;
	29	}
	30	if (!(x & 3)) {
	31	x >>= 2;
	32	r += 2;
	33	}
	34	if (!(x & 1)) {
	35	x >>= 1;
	36	r += 1;
	37	}
	38	return r;
	39	}
	40
52d61227 SK	41	/**
	42	* fls - find last (most-significant) bit set
	43	* @x: the word to search
	44	*
	45	* This is defined the same way as ffs.
	46	* Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
	47	*/
	48	static inline int generic_fls(int x)
	49	{
	50	int r = 32;
	51
	52	if (!x)
	53	return 0;
	54	if (!(x & 0xffff0000u)) {
	55	x <<= 16;
	56	r -= 16;
	57	}
	58	if (!(x & 0xff000000u)) {
	59	x <<= 8;
	60	r -= 8;
	61	}
	62	if (!(x & 0xf0000000u)) {
	63	x <<= 4;
	64	r -= 4;
	65	}
	66	if (!(x & 0xc0000000u)) {
	67	x <<= 2;
	68	r -= 2;
	69	}
	70	if (!(x & 0x80000000u)) {
	71	x <<= 1;
	72	r -= 1;
	73	}
	74	return r;
	75	}
	76
	77
b15cbc0b WD	78	/*
	79	* hweightN: returns the hamming weight (i.e. the number
	80	* of bits set) of a N-bit word
	81	*/
	82
	83	static inline unsigned int generic_hweight32(unsigned int w)
	84	{
8bde7f77 WD	85	unsigned int res = (w & 0x55555555) + ((w >> 1) & 0x55555555);
	86	res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
	87	res = (res & 0x0F0F0F0F) + ((res >> 4) & 0x0F0F0F0F);
	88	res = (res & 0x00FF00FF) + ((res >> 8) & 0x00FF00FF);
	89	return (res & 0x0000FFFF) + ((res >> 16) & 0x0000FFFF);
b15cbc0b WD	90	}
	91
	92	static inline unsigned int generic_hweight16(unsigned int w)
	93	{
8bde7f77 WD	94	unsigned int res = (w & 0x5555) + ((w >> 1) & 0x5555);
	95	res = (res & 0x3333) + ((res >> 2) & 0x3333);
	96	res = (res & 0x0F0F) + ((res >> 4) & 0x0F0F);
	97	return (res & 0x00FF) + ((res >> 8) & 0x00FF);
b15cbc0b WD	98	}
	99
	100	static inline unsigned int generic_hweight8(unsigned int w)
	101	{
8bde7f77 WD	102	unsigned int res = (w & 0x55) + ((w >> 1) & 0x55);
	103	res = (res & 0x33) + ((res >> 2) & 0x33);
	104	return (res & 0x0F) + ((res >> 4) & 0x0F);
b15cbc0b WD	105	}
b15cbc0b WD	106
02f99901 SK	107	#define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG))
	108	#define BIT_WORD(nr) ((nr) / BITS_PER_LONG)
	109
b15cbc0b WD	110	#include <asm/bitops.h>
b15cbc0b WD	111
02f99901 SK	112	/* linux/include/asm-generic/bitops/non-atomic.h */
02f99901 SK	113
0413cfec	114	#ifndef PLATFORM__SET_BIT
02f99901 SK	115	# define __set_bit generic_set_bit
	116	#endif
	117
0413cfec	118	#ifndef PLATFORM__CLEAR_BIT
02f99901 SK	119	# define __clear_bit generic_clear_bit
	120	#endif
	121
0413cfec	122	#ifndef PLATFORM_FFS
52d61227 SK	123	# define ffs generic_ffs
	124	#endif
	125
0413cfec	126	#ifndef PLATFORM_FLS
52d61227 SK	127	# define fls generic_fls
	128	#endif
	129
02f99901 SK	130	/**
	131	* __set_bit - Set a bit in memory
	132	* @nr: the bit to set
	133	* @addr: the address to start counting from
	134	*
	135	* Unlike set_bit(), this function is non-atomic and may be reordered.
	136	* If it's called on the same region of memory simultaneously, the effect
	137	* may be that only one operation succeeds.
	138	*/
	139	static inline void generic_set_bit(int nr, volatile unsigned long *addr)
	140	{
	141	unsigned long mask = BIT_MASK(nr);
	142	unsigned long p = ((unsigned long )addr) + BIT_WORD(nr);
	143
	144	*p \|= mask;
	145	}
	146
	147	static inline void generic_clear_bit(int nr, volatile unsigned long *addr)
	148	{
	149	unsigned long mask = BIT_MASK(nr);
	150	unsigned long p = ((unsigned long )addr) + BIT_WORD(nr);
	151
	152	*p &= ~mask;
	153	}
b15cbc0b WD	154
b15cbc0b WD	155	#endif