summaryrefslogtreecommitdiffstats
path: root/arch/arm/lib/changebit.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/lib/changebit.S')
-rw-r--r--arch/arm/lib/changebit.S28
1 files changed, 28 insertions, 0 deletions
diff --git a/arch/arm/lib/changebit.S b/arch/arm/lib/changebit.S
new file mode 100644
index 00000000000..3af45cab70e
--- /dev/null
+++ b/arch/arm/lib/changebit.S
@@ -0,0 +1,28 @@
+/*
+ * linux/arch/arm/lib/changebit.S
+ *
+ * Copyright (C) 1995-1996 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+ .text
+
+/* Purpose : Function to change a bit
+ * Prototype: int change_bit(int bit, void *addr)
+ */
+ENTRY(_change_bit_be)
+ eor r0, r0, #0x18 @ big endian byte ordering
+ENTRY(_change_bit_le)
+ and r2, r0, #7
+ mov r3, #1
+ mov r3, r3, lsl r2
+ save_and_disable_irqs ip, r2
+ ldrb r2, [r1, r0, lsr #3]
+ eor r2, r2, r3
+ strb r2, [r1, r0, lsr #3]
+ restore_irqs ip
+ RETINSTR(mov,pc,lr)