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Diffstat (limited to 'arch/loongarch/include/asm/cmpxchg.h')
-rw-r--r--arch/loongarch/include/asm/cmpxchg.h48
1 files changed, 37 insertions, 11 deletions
diff --git a/arch/loongarch/include/asm/cmpxchg.h b/arch/loongarch/include/asm/cmpxchg.h
index 979fde61bba8..0494c2ab553e 100644
--- a/arch/loongarch/include/asm/cmpxchg.h
+++ b/arch/loongarch/include/asm/cmpxchg.h
@@ -9,17 +9,33 @@
#include <linux/build_bug.h>
#include <asm/barrier.h>
-#define __xchg_asm(amswap_db, m, val) \
+#define __xchg_amo_asm(amswap_db, m, val) \
({ \
- __typeof(val) __ret; \
+ __typeof(val) __ret; \
\
- __asm__ __volatile__ ( \
- " "amswap_db" %1, %z2, %0 \n" \
- : "+ZB" (*m), "=&r" (__ret) \
- : "Jr" (val) \
- : "memory"); \
+ __asm__ __volatile__ ( \
+ " "amswap_db" %1, %z2, %0 \n" \
+ : "+ZB" (*m), "=&r" (__ret) \
+ : "Jr" (val) \
+ : "memory"); \
\
- __ret; \
+ __ret; \
+})
+
+#define __xchg_llsc_asm(ld, st, m, val) \
+({ \
+ __typeof(val) __ret, __tmp; \
+ \
+ asm volatile ( \
+ "1: ll.w %0, %3 \n" \
+ " move %1, %z4 \n" \
+ " sc.w %1, %2 \n" \
+ " beqz %1, 1b \n" \
+ : "=&r" (__ret), "=&r" (__tmp), "=ZC" (*m) \
+ : "ZC" (*m), "Jr" (val) \
+ : "memory"); \
+ \
+ __ret; \
})
static inline unsigned int __xchg_small(volatile void *ptr, unsigned int val,
@@ -67,13 +83,23 @@ __arch_xchg(volatile void *ptr, unsigned long x, int size)
switch (size) {
case 1:
case 2:
- return __xchg_small(ptr, x, size);
+ return __xchg_small((volatile void *)ptr, x, size);
case 4:
- return __xchg_asm("amswap_db.w", (volatile u32 *)ptr, (u32)x);
+#ifdef CONFIG_CPU_HAS_AMO
+ return __xchg_amo_asm("amswap_db.w", (volatile u32 *)ptr, (u32)x);
+#else
+ return __xchg_llsc_asm("ll.w", "sc.w", (volatile u32 *)ptr, (u32)x);
+#endif /* CONFIG_CPU_HAS_AMO */
+#ifdef CONFIG_64BIT
case 8:
- return __xchg_asm("amswap_db.d", (volatile u64 *)ptr, (u64)x);
+#ifdef CONFIG_CPU_HAS_AMO
+ return __xchg_amo_asm("amswap_db.d", (volatile u64 *)ptr, (u64)x);
+#else
+ return __xchg_llsc_asm("ll.d", "sc.d", (volatile u64 *)ptr, (u64)x);
+#endif /* CONFIG_CPU_HAS_AMO */
+#endif /* CONFIG_64BIT */
default:
BUILD_BUG();