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authorSteven Whitehouse <swhiteho@redhat.com>2006-09-28 08:29:59 -0400
committerSteven Whitehouse <swhiteho@redhat.com>2006-09-28 08:29:59 -0400
commit185a257f2f73bcd89050ad02da5bedbc28fc43fa (patch)
tree5e32586114534ed3f2165614cba3d578f5d87307 /include/asm-avr32/timex.h
parent3f1a9aaeffd8d1cbc5ab9776c45cbd66af1c9699 (diff)
parenta77c64c1a641950626181b4857abb701d8f38ccc (diff)
downloadlinux-rt-185a257f2f73bcd89050ad02da5bedbc28fc43fa.tar.gz
Merge branch 'master' into gfs2
Diffstat (limited to 'include/asm-avr32/timex.h')
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diff --git a/include/asm-avr32/timex.h b/include/asm-avr32/timex.h
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+/*
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * 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.
+ */
+#ifndef __ASM_AVR32_TIMEX_H
+#define __ASM_AVR32_TIMEX_H
+
+/*
+ * This is the frequency of the timer used for Linux's timer interrupt.
+ * The value should be defined as accurate as possible or under certain
+ * circumstances Linux timekeeping might become inaccurate or fail.
+ *
+ * For many system the exact clockrate of the timer isn't known but due to
+ * the way this value is used we can get away with a wrong value as long
+ * as this value is:
+ *
+ * - a multiple of HZ
+ * - a divisor of the actual rate
+ *
+ * 500000 is a good such cheat value.
+ *
+ * The obscure number 1193182 is the same as used by the original i8254
+ * time in legacy PC hardware; the chip is never found in AVR32 systems.
+ */
+#define CLOCK_TICK_RATE 500000 /* Underlying HZ */
+
+typedef unsigned long cycles_t;
+
+static inline cycles_t get_cycles (void)
+{
+ return 0;
+}
+
+extern int read_current_timer(unsigned long *timer_value);
+#define ARCH_HAS_READ_CURRENT_TIMER 1
+
+#endif /* __ASM_AVR32_TIMEX_H */