aboutsummaryrefslogtreecommitdiff
path: root/arch/h8300/include/asm/delay.h
diff options
context:
space:
mode:
authorJames Morris <jmorris@namei.org>2008-08-28 10:47:34 +1000
committerJames Morris <jmorris@namei.org>2008-08-28 10:47:34 +1000
commit86d688984deefa3ae5a802880c11f2b408b5d6cf (patch)
tree7ea5e8189b0a774626d3ed7c3c87df2495a4c4a0 /arch/h8300/include/asm/delay.h
parent93c06cbbf9fea5d5be1778febb7fa9ab1a74e5f5 (diff)
parent4c246edd2550304df5b766cc841584b2bb058843 (diff)
Merge branch 'master' into next
Diffstat (limited to 'arch/h8300/include/asm/delay.h')
-rw-r--r--arch/h8300/include/asm/delay.h38
1 files changed, 38 insertions, 0 deletions
diff --git a/arch/h8300/include/asm/delay.h b/arch/h8300/include/asm/delay.h
new file mode 100644
index 00000000000..743beba70f8
--- /dev/null
+++ b/arch/h8300/include/asm/delay.h
@@ -0,0 +1,38 @@
+#ifndef _H8300_DELAY_H
+#define _H8300_DELAY_H
+
+#include <asm/param.h>
+
+/*
+ * Copyright (C) 2002 Yoshinori Sato <ysato@sourceforge.jp>
+ *
+ * Delay routines, using a pre-computed "loops_per_second" value.
+ */
+
+static inline void __delay(unsigned long loops)
+{
+ __asm__ __volatile__ ("1:\n\t"
+ "dec.l #1,%0\n\t"
+ "bne 1b"
+ :"=r" (loops):"0"(loops));
+}
+
+/*
+ * Use only for very small delays ( < 1 msec). Should probably use a
+ * lookup table, really, as the multiplications take much too long with
+ * short delays. This is a "reasonable" implementation, though (and the
+ * first constant multiplications gets optimized away if the delay is
+ * a constant)
+ */
+
+extern unsigned long loops_per_jiffy;
+
+static inline void udelay(unsigned long usecs)
+{
+ usecs *= 4295; /* 2**32 / 1000000 */
+ usecs /= (loops_per_jiffy*HZ);
+ if (usecs)
+ __delay(usecs);
+}
+
+#endif /* _H8300_DELAY_H */