summaryrefslogtreecommitdiffstats
path: root/arch/arm/lib/testclearbit.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/lib/testclearbit.S')
-rw-r--r--arch/arm/lib/testclearbit.S25
1 files changed, 25 insertions, 0 deletions
diff --git a/arch/arm/lib/testclearbit.S b/arch/arm/lib/testclearbit.S
new file mode 100644
index 000000000..431865302
--- /dev/null
+++ b/arch/arm/lib/testclearbit.S
@@ -0,0 +1,25 @@
+/*
+ * linux/arch/arm/lib/testclearbit.S
+ *
+ * Copyright (C) 1995-1996 Russell King
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+ .text
+
+ENTRY(test_and_clear_bit)
+ add r1, r1, r0, lsr #3 @ Get byte offset
+ and r3, r0, #7 @ Get bit offset
+ mov r0, #1
+ SAVEIRQS(ip)
+ DISABLEIRQS(ip)
+ ldrb r2, [r1]
+ tst r2, r0, lsl r3
+ bic r2, r2, r0, lsl r3
+ moveq r0, #0
+ strb r2, [r1]
+ RESTOREIRQS(ip)
+ RETINSTR(mov,pc,lr)
+
+