linux_dsm_epyc7002/arch/csky/include/asm/cmpxchg.h
Guo Ren a0ae62806f csky: Atomic operations
This patch adds atomic, cmpxchg, spinlock files.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Andrea Parri <andrea.parri@amarulasolutions.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Peter Zijlstra <peterz@infradead.org>
2018-10-26 00:54:23 +08:00

74 lines
1.6 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_CSKY_CMPXCHG_H
#define __ASM_CSKY_CMPXCHG_H
#ifdef CONFIG_CPU_HAS_LDSTEX
#include <asm/barrier.h>
extern void __bad_xchg(void);
#define __xchg(new, ptr, size) \
({ \
__typeof__(ptr) __ptr = (ptr); \
__typeof__(new) __new = (new); \
__typeof__(*(ptr)) __ret; \
unsigned long tmp; \
switch (size) { \
case 4: \
smp_mb(); \
asm volatile ( \
"1: ldex.w %0, (%3) \n" \
" mov %1, %2 \n" \
" stex.w %1, (%3) \n" \
" bez %1, 1b \n" \
: "=&r" (__ret), "=&r" (tmp) \
: "r" (__new), "r"(__ptr) \
:); \
smp_mb(); \
break; \
default: \
__bad_xchg(); \
} \
__ret; \
})
#define xchg(ptr, x) (__xchg((x), (ptr), sizeof(*(ptr))))
#define __cmpxchg(ptr, old, new, size) \
({ \
__typeof__(ptr) __ptr = (ptr); \
__typeof__(new) __new = (new); \
__typeof__(new) __tmp; \
__typeof__(old) __old = (old); \
__typeof__(*(ptr)) __ret; \
switch (size) { \
case 4: \
smp_mb(); \
asm volatile ( \
"1: ldex.w %0, (%3) \n" \
" cmpne %0, %4 \n" \
" bt 2f \n" \
" mov %1, %2 \n" \
" stex.w %1, (%3) \n" \
" bez %1, 1b \n" \
"2: \n" \
: "=&r" (__ret), "=&r" (__tmp) \
: "r" (__new), "r"(__ptr), "r"(__old) \
:); \
smp_mb(); \
break; \
default: \
__bad_xchg(); \
} \
__ret; \
})
#define cmpxchg(ptr, o, n) \
(__cmpxchg((ptr), (o), (n), sizeof(*(ptr))))
#else
#include <asm-generic/cmpxchg.h>
#endif
#endif /* __ASM_CSKY_CMPXCHG_H */