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authorJeff Garzik <jeff@garzik.org>2006-09-26 19:13:19 +0200
committerJeff Garzik <jeff@garzik.org>2006-09-26 19:13:19 +0200
commitc226951b93f7cd7c3a10b17384535b617bd43fd0 (patch)
tree07b8796a5c99fbbf587b8d0dbcbc173cfe5e381e /include/asm-avr32/timex.h
parentMerge branch 'upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/linv... (diff)
parent[PATCH] s390: fix cmm kernel thread handling (diff)
downloadlinux-c226951b93f7cd7c3a10b17384535b617bd43fd0.tar.xz
linux-c226951b93f7cd7c3a10b17384535b617bd43fd0.zip
Merge branch 'master' into upstream
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 */