text: /* SPDX-License-Identifier: GPL-2.0 */
  
  #ifndef __ASM_CSKY_CMPXCHG_H
  #define __ASM_CSKY_CMPXCHG_H
  
  #ifdef CONFIG_SMP
  #include <asm/barrier.h>
  
  extern void __bad_xchg(void);
  
  #define __xchg_relaxed(new, ptr, size)				\
  ({								\
  	__typeof__(ptr) __ptr = (ptr);				\
  	__typeof__(new) __new = (new);				\
  	__typeof__(*(ptr)) __ret;				\
  	unsigned long tmp;					\
  	switch (size) {						\
  	case 4:							\
  		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)		\
  			:);					\
  		break;						\
  	default:						\
  		__bad_xchg();					\
  	}							\
  	__ret;							\
  })
  
  #define arch_xchg_relaxed(ptr, x) \
  		(__xchg_relaxed((x), (ptr), sizeof(*(ptr))))
  
  #define __cmpxchg_relaxed(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:							\
  		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)	\
  			:);					\
  		break;						\
  	default:						\
  		__bad_xchg();					\
  	}							\
  	__ret;							\
  })
  
  #define arch_cmpxchg_relaxed(ptr, o, n) \
  	(__cmpxchg_relaxed((ptr), (o), (n), sizeof(*(ptr))))
  
  #define arch_cmpxchg(ptr, o, n) 				\
  ({								\
  	__typeof__(*(ptr)) __ret;				\
  	__smp_release_fence();					\
  	__ret = arch_cmpxchg_relaxed(ptr, o, n);		\
  	__smp_acquire_fence();					\
  	__ret;							\
  })
  
  #else
  #include <asm-generic/cmpxchg.h>
  #endif
  
  #endif /* __ASM_CSKY_CMPXCHG_H */
  