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x86: use standard PIT frequency

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the RDC and ELAN platforms use slighly different PIT clocks, resulting in
a timex.h hack that changes PIT_TICK_RATE during build time. But if a
tester enables any of these platform support .config options, the PIT
will be miscalibrated on standard PC platforms.

So use one frequency - in a subsequent patch we'll add a quirk to allow
x86 platforms to define different PIT frequencies.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Ingo Molnar
2009-01-25 16:57:00 +01:00
parent ff4ce8c332
commit e1b4d11436
1 changed files with 4 additions and 9 deletions
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13
arch/x86/include/asm/timex.h
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@@ -1,18 +1,13 @@
/* x86 architecture timex specifications */
#ifndef _ASM_X86_TIMEX_H #ifndef _ASM_X86_TIMEX_H
#define _ASM_X86_TIMEX_H #define _ASM_X86_TIMEX_H
#include <asm/processor.h> #include <asm/processor.h>
#include <asm/tsc.h> #include <asm/tsc.h>
#ifdef CONFIG_X86_ELAN /* The PIT ticks at this frequency (in HZ): */
# define PIT_TICK_RATE 1189200 /* AMD Elan has different frequency! */ #define PIT_TICK_RATE 1193182
#elif defined(CONFIG_X86_RDC321X)
# define PIT_TICK_RATE 1041667 /* Underlying HZ for R8610 */ #define CLOCK_TICK_RATE PIT_TICK_RATE
#else
# define PIT_TICK_RATE 1193182 /* Underlying HZ */
#endif
#define CLOCK_TICK_RATE PIT_TICK_RATE
#define ARCH_HAS_READ_CURRENT_TIMER #define ARCH_HAS_READ_CURRENT_TIMER