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-rw-r--r--include/asm-h8300/delay.h38
1 files changed, 38 insertions, 0 deletions
diff --git a/include/asm-h8300/delay.h b/include/asm-h8300/delay.h
new file mode 100644
index 000000000000..cbccbbdd640f
--- /dev/null
+++ b/include/asm-h8300/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.
+ */
+
+extern __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;
+
+extern __inline__ void udelay(unsigned long usecs)
+{
+ usecs *= 4295; /* 2**32 / 1000000 */
+ usecs /= (loops_per_jiffy*HZ);
+ if (usecs)
+ __delay(usecs);
+}
+
+#endif /* _H8300_DELAY_H */