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-rw-r--r--include/asm-mips/timex.h25
1 files changed, 5 insertions, 20 deletions
diff --git a/include/asm-mips/timex.h b/include/asm-mips/timex.h
index 87c68ae76ff8..5816ad1569d6 100644
--- a/include/asm-mips/timex.h
+++ b/include/asm-mips/timex.h
@@ -13,27 +13,12 @@
13#include <asm/mipsregs.h> 13#include <asm/mipsregs.h>
14 14
15/* 15/*
16 * This is the frequency of the timer used for Linux's timer interrupt. 16 * This is the clock rate of the i8253 PIT. A MIPS system may not have
17 * The value should be defined as accurate as possible or under certain 17 * a PIT by the symbol is used all over the kernel including some APIs.
18 * circumstances Linux timekeeping might become inaccurate or fail. 18 * So keeping it defined to the number for the PIT is the only sane thing
19 * 19 * for now.
20 * For many system the exact clockrate of the timer isn't known but due to
21 * the way this value is used we can get away with a wrong value as long
22 * as this value is:
23 *
24 * - a multiple of HZ
25 * - a divisor of the actual rate
26 *
27 * 500000 is a good such cheat value.
28 *
29 * The obscure number 1193182 is the same as used by the original i8254
30 * time in legacy PC hardware; the chip unfortunately also found in a
31 * bunch of MIPS systems. The last remaining user of the i8254 for the
32 * timer interrupt is the RM200; it's a very standard system so there is
33 * no reason to make this a separate architecture.
34 */ 20 */
35 21#define CLOCK_TICK_RATE 1193182
36#include <timex.h>
37 22
38/* 23/*
39 * Standard way to access the cycle counter. 24 * Standard way to access the cycle counter.