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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-frv/delay.h
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'include/asm-frv/delay.h')
-rw-r--r--include/asm-frv/delay.h50
1 files changed, 50 insertions, 0 deletions
diff --git a/include/asm-frv/delay.h b/include/asm-frv/delay.h
new file mode 100644
index 000000000000..597b4ebf03b4
--- /dev/null
+++ b/include/asm-frv/delay.h
@@ -0,0 +1,50 @@
+/* delay.h: FRV delay code
+ *
+ * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _ASM_DELAY_H
+#define _ASM_DELAY_H
+
+#include <asm/param.h>
+#include <asm/timer-regs.h>
+
+/*
+ * delay loop - runs at __core_clock_speed_HZ / 2 [there are 2 insns in the loop]
+ */
+extern unsigned long __delay_loops_MHz;
+
+static inline void __delay(unsigned long loops)
+{
+ asm volatile("1: subicc %0,#1,%0,icc0 \n"
+ " bnc icc0,#2,1b \n"
+ : "=r" (loops)
+ : "0" (loops)
+ : "icc0"
+ );
+}
+
+/*
+ * 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)
+{
+ __delay(usecs * __delay_loops_MHz);
+}
+
+#define ndelay(n) udelay((n) * 5)
+
+#endif /* _ASM_DELAY_H */