u-boot/arch/sh/include/asm/bitops.h

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#ifndef __ASM_SH_BITOPS_H
#define __ASM_SH_BITOPS_H
#ifdef __KERNEL__
#include <asm/irqflags.h>
/* For __swab32 */
#include <asm/byteorder.h>
static inline void set_bit(int nr, volatile void * addr)
{
int mask;
volatile unsigned int *a = addr;
unsigned long flags;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
local_irq_save(flags);
*a |= mask;
local_irq_restore(flags);
}
/*
* clear_bit() doesn't provide any barrier for the compiler.
*/
#define smp_mb__before_clear_bit() barrier()
#define smp_mb__after_clear_bit() barrier()
static inline void clear_bit(int nr, volatile void * addr)
{
int mask;
volatile unsigned int *a = addr;
unsigned long flags;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
local_irq_save(flags);
*a &= ~mask;
local_irq_restore(flags);
}
static inline void change_bit(int nr, volatile void * addr)
{
int mask;
volatile unsigned int *a = addr;
unsigned long flags;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
local_irq_save(flags);
*a ^= mask;
local_irq_restore(flags);
}
static inline int test_and_set_bit(int nr, volatile void * addr)
{
int mask, retval;
volatile unsigned int *a = addr;
unsigned long flags;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
local_irq_save(flags);
retval = (mask & *a) != 0;
*a |= mask;
local_irq_restore(flags);
return retval;
}
static inline int test_and_clear_bit(int nr, volatile void * addr)
{
int mask, retval;
volatile unsigned int *a = addr;
unsigned long flags;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
local_irq_save(flags);
retval = (mask & *a) != 0;
*a &= ~mask;
local_irq_restore(flags);
return retval;
}
static inline int test_and_change_bit(int nr, volatile void * addr)
{
int mask, retval;
volatile unsigned int *a = addr;
unsigned long flags;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
local_irq_save(flags);
retval = (mask & *a) != 0;
*a ^= mask;
local_irq_restore(flags);
return retval;
}
static inline unsigned long ffz(unsigned long word)
{
unsigned long result;
__asm__("1:\n\t"
"shlr %1\n\t"
"bt/s 1b\n\t"
" add #1, %0"
: "=r" (result), "=r" (word)
: "0" (~0L), "1" (word)
: "t");
return result;
}
/**
* ffs - find first bit in word.
* @word: The word to search
*
* Undefined if no bit exists, so code should check against 0 first.
*/
static inline int 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;
}
#define PLATFORM_FFS
#endif /* __KERNEL__ */
#endif /* __ASM_SH_BITOPS_H */