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#ifndef __ASM_SH_CMPXCHG_LLSC_H
#define __ASM_SH_CMPXCHG_LLSC_H
#include <linux/bitops.h>
#include <asm/byteorder.h>
static inline unsigned long xchg_u32(volatile u32 *m, unsigned long val)
{
unsigned long retval;
unsigned long tmp;
__asm__ __volatile__ (
"1: \n\t"
"movli.l @%2, %0 ! xchg_u32 \n\t"
"mov %0, %1 \n\t"
"mov %3, %0 \n\t"
"movco.l %0, @%2 \n\t"
"bf 1b \n\t"
"synco \n\t"
: "=&z"(tmp), "=&r" (retval)
: "r" (m), "r" (val)
: "t", "memory"
);
return retval;
}
static inline unsigned long
__cmpxchg_u32(volatile u32 *m, unsigned long old, unsigned long new)
{
unsigned long retval;
unsigned long tmp;
__asm__ __volatile__ (
"1: \n\t"
"movli.l @%2, %0 ! __cmpxchg_u32 \n\t"
"mov %0, %1 \n\t"
"cmp/eq %1, %3 \n\t"
"bf 2f \n\t"
"mov %4, %0 \n\t"
"2: \n\t"
"movco.l %0, @%2 \n\t"
"bf 1b \n\t"
"synco \n\t"
: "=&z" (tmp), "=&r" (retval)
: "r" (m), "r" (old), "r" (new)
: "t", "memory"
);
return retval;
}
static inline u32 __xchg_cmpxchg(volatile void *ptr, u32 x, int size)
{
int off = (unsigned long)ptr % sizeof(u32);
volatile u32 *p = ptr - off;
#ifdef __BIG_ENDIAN
int bitoff = (sizeof(u32) - 1 - off) * BITS_PER_BYTE;
#else
int bitoff = off * BITS_PER_BYTE;
#endif
u32 bitmask = ((0x1 << size * BITS_PER_BYTE) - 1) << bitoff;
u32 oldv, newv;
u32 ret;
do {
oldv = READ_ONCE(*p);
ret = (oldv & bitmask) >> bitoff;
newv = (oldv & ~bitmask) | (x << bitoff);
} while (__cmpxchg_u32(p, oldv, newv) != oldv);
return ret;
}
static inline unsigned long xchg_u16(volatile u16 *m, unsigned long val)
{
return __xchg_cmpxchg(m, val, sizeof *m);
}
static inline unsigned long xchg_u8(volatile u8 *m, unsigned long val)
{
return __xchg_cmpxchg(m, val, sizeof *m);
}
#endif /* __ASM_SH_CMPXCHG_LLSC_H */
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