summaryrefslogtreecommitdiff
path: root/arch/nios2/include/asm/cmpxchg.h
diff options
context:
space:
mode:
authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/nios2/include/asm/cmpxchg.h
Initial import
Diffstat (limited to 'arch/nios2/include/asm/cmpxchg.h')
-rw-r--r--arch/nios2/include/asm/cmpxchg.h61
1 files changed, 61 insertions, 0 deletions
diff --git a/arch/nios2/include/asm/cmpxchg.h b/arch/nios2/include/asm/cmpxchg.h
new file mode 100644
index 000000000..859387115
--- /dev/null
+++ b/arch/nios2/include/asm/cmpxchg.h
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_CMPXCHG_H
+#define _ASM_NIOS2_CMPXCHG_H
+
+#include <linux/irqflags.h>
+
+#define xchg(ptr, x) \
+ ((__typeof__(*(ptr)))__xchg((unsigned long)(x), (ptr), sizeof(*(ptr))))
+
+struct __xchg_dummy { unsigned long a[100]; };
+#define __xg(x) ((volatile struct __xchg_dummy *)(x))
+
+static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
+ int size)
+{
+ unsigned long tmp, flags;
+
+ local_irq_save(flags);
+
+ switch (size) {
+ case 1:
+ __asm__ __volatile__(
+ "ldb %0, %2\n"
+ "stb %1, %2\n"
+ : "=&r" (tmp)
+ : "r" (x), "m" (*__xg(ptr))
+ : "memory");
+ break;
+ case 2:
+ __asm__ __volatile__(
+ "ldh %0, %2\n"
+ "sth %1, %2\n"
+ : "=&r" (tmp)
+ : "r" (x), "m" (*__xg(ptr))
+ : "memory");
+ break;
+ case 4:
+ __asm__ __volatile__(
+ "ldw %0, %2\n"
+ "stw %1, %2\n"
+ : "=&r" (tmp)
+ : "r" (x), "m" (*__xg(ptr))
+ : "memory");
+ break;
+ }
+
+ local_irq_restore(flags);
+ return tmp;
+}
+
+#include <asm-generic/cmpxchg.h>
+#include <asm-generic/cmpxchg-local.h>
+
+#endif /* _ASM_NIOS2_CMPXCHG_H */