cmpxchg.h

  1/* SPDX-License-Identifier: GPL-2.0 */
  2
  3#ifndef __ASM_CSKY_CMPXCHG_H
  4#define __ASM_CSKY_CMPXCHG_H
  5
  6#ifdef CONFIG_SMP
  7#include <linux/bug.h>
  8#include <asm/barrier.h>
  9#include <linux/cmpxchg-emu.h>
 10
 11#define __xchg_relaxed(new, ptr, size)				\
 12({								\
 13	__typeof__(ptr) __ptr = (ptr);				\
 14	__typeof__(new) __new = (new);				\
 15	__typeof__(*(ptr)) __ret;				\
 16	unsigned long tmp;					\
 17	switch (size) {						\
 18	case 2: {						\
 19		u32 ret;					\
 20		u32 shif = ((ulong)__ptr & 2) ? 16 : 0;		\
 21		u32 mask = 0xffff << shif;			\
 22		__ptr = (__typeof__(ptr))((ulong)__ptr & ~2);	\
 23		__asm__ __volatile__ (				\
 24			"1:	ldex.w %0, (%4)\n"		\
 25			"	and    %1, %0, %2\n"		\
 26			"	or     %1, %1, %3\n"		\
 27			"	stex.w %1, (%4)\n"		\
 28			"	bez    %1, 1b\n"		\
 29			: "=&r" (ret), "=&r" (tmp)		\
 30			: "r" (~mask),				\
 31			  "r" ((u32)__new << shif),		\
 32			  "r" (__ptr)				\
 33			: "memory");				\
 34		__ret = (__typeof__(*(ptr)))			\
 35			((ret & mask) >> shif);			\
 36		break;						\
 37	}							\
 38	case 4:							\
 39		asm volatile (					\
 40		"1:	ldex.w		%0, (%3) \n"		\
 41		"	mov		%1, %2   \n"		\
 42		"	stex.w		%1, (%3) \n"		\
 43		"	bez		%1, 1b   \n"		\
 44			: "=&r" (__ret), "=&r" (tmp)		\
 45			: "r" (__new), "r"(__ptr)		\
 46			:);					\
 47		break;						\
 48	default:						\
 49		BUILD_BUG();					\
 50	}							\
 51	__ret;							\
 52})
 53
 54#define arch_xchg_relaxed(ptr, x) \
 55		(__xchg_relaxed((x), (ptr), sizeof(*(ptr))))
 56
 57#define __cmpxchg_relaxed(ptr, old, new, size)			\
 58({								\
 59	__typeof__(ptr) __ptr = (ptr);				\
 60	__typeof__(new) __new = (new);				\
 61	__typeof__(new) __tmp;					\
 62	__typeof__(old) __old = (old);				\
 63	__typeof__(*(ptr)) __ret;				\
 64	switch (size) {						\
 65	case 1:							\
 66		__ret = (__typeof__(*(ptr)))cmpxchg_emu_u8((volatile u8 *)__ptr, (uintptr_t)__old, (uintptr_t)__new); \
 67		break;						\
 68	case 4:							\
 69		asm volatile (					\
 70		"1:	ldex.w		%0, (%3) \n"		\
 71		"	cmpne		%0, %4   \n"		\
 72		"	bt		2f       \n"		\
 73		"	mov		%1, %2   \n"		\
 74		"	stex.w		%1, (%3) \n"		\
 75		"	bez		%1, 1b   \n"		\
 76		"2:				 \n"		\
 77			: "=&r" (__ret), "=&r" (__tmp)		\
 78			: "r" (__new), "r"(__ptr), "r"(__old)	\
 79			:);					\
 80		break;						\
 81	default:						\
 82		BUILD_BUG();					\
 83	}							\
 84	__ret;							\
 85})
 86
 87#define arch_cmpxchg_relaxed(ptr, o, n) \
 88	(__cmpxchg_relaxed((ptr), (o), (n), sizeof(*(ptr))))
 89
 90#define __cmpxchg_acquire(ptr, old, new, size)			\
 91({								\
 92	__typeof__(ptr) __ptr = (ptr);				\
 93	__typeof__(new) __new = (new);				\
 94	__typeof__(new) __tmp;					\
 95	__typeof__(old) __old = (old);				\
 96	__typeof__(*(ptr)) __ret;				\
 97	switch (size) {						\
 98	case 1:							\
 99		__ret = (__typeof__(*(ptr)))cmpxchg_emu_u8((volatile u8 *)__ptr, (uintptr_t)__old, (uintptr_t)__new); \
100		break;						\
101	case 4:							\
102		asm volatile (					\
103		"1:	ldex.w		%0, (%3) \n"		\
104		"	cmpne		%0, %4   \n"		\
105		"	bt		2f       \n"		\
106		"	mov		%1, %2   \n"		\
107		"	stex.w		%1, (%3) \n"		\
108		"	bez		%1, 1b   \n"		\
109		ACQUIRE_FENCE					\
110		"2:				 \n"		\
111			: "=&r" (__ret), "=&r" (__tmp)		\
112			: "r" (__new), "r"(__ptr), "r"(__old)	\
113			:);					\
114		break;						\
115	default:						\
116		BUILD_BUG();					\
117	}							\
118	__ret;							\
119})
120
121#define arch_cmpxchg_acquire(ptr, o, n) \
122	(__cmpxchg_acquire((ptr), (o), (n), sizeof(*(ptr))))
123
124#define __cmpxchg(ptr, old, new, size)				\
125({								\
126	__typeof__(ptr) __ptr = (ptr);				\
127	__typeof__(new) __new = (new);				\
128	__typeof__(new) __tmp;					\
129	__typeof__(old) __old = (old);				\
130	__typeof__(*(ptr)) __ret;				\
131	switch (size) {						\
132	case 1:							\
133		__ret = (__typeof__(*(ptr)))cmpxchg_emu_u8((volatile u8 *)__ptr, (uintptr_t)__old, (uintptr_t)__new); \
134		break;						\
135	case 4:							\
136		asm volatile (					\
137		RELEASE_FENCE					\
138		"1:	ldex.w		%0, (%3) \n"		\
139		"	cmpne		%0, %4   \n"		\
140		"	bt		2f       \n"		\
141		"	mov		%1, %2   \n"		\
142		"	stex.w		%1, (%3) \n"		\
143		"	bez		%1, 1b   \n"		\
144		FULL_FENCE					\
145		"2:				 \n"		\
146			: "=&r" (__ret), "=&r" (__tmp)		\
147			: "r" (__new), "r"(__ptr), "r"(__old)	\
148			:);					\
149		break;						\
150	default:						\
151		BUILD_BUG();					\
152	}							\
153	__ret;							\
154})
155
156#define arch_cmpxchg(ptr, o, n)					\
157	(__cmpxchg((ptr), (o), (n), sizeof(*(ptr))))
158
159#define arch_cmpxchg_local(ptr, o, n)				\
160	(__cmpxchg_relaxed((ptr), (o), (n), sizeof(*(ptr))))
161#else
162#include <asm-generic/cmpxchg.h>
163#endif
164
165#endif /* __ASM_CSKY_CMPXCHG_H */