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Subject[PATCH -tip] x86: apic LVTT - use APIC_DIVISOR on 64bit mode
We use APIC_TDR_DIV_16 while setting APIC_TDCR (divisor)
it happened this moment is hidden from __setup_APIC_LVTT
caller. So we better increment caller 'clocks' value to
not change current behaviour and use APIC_DIVISOR
(as already done in 32bit version).

The main benefit - unified procedure code for 32/64bit modes.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
CC: "Maciej W. Rozycki" <macro@linux-mips.org>
---

Please review carefully. Any comments are welcome.
I'm _not_ 100% sure if this patch is safe.

Index: linux-2.6.git/arch/x86/kernel/apic_64.c
===================================================================
--- linux-2.6.git.orig/arch/x86/kernel/apic_64.c 2008-07-08 22:52:24.000000000 +0400
+++ linux-2.6.git/arch/x86/kernel/apic_64.c 2008-07-08 23:00:24.000000000 +0400
@@ -165,6 +165,9 @@ int lapic_get_maxlvt(void)
return maxlvt;
}

+/* Clock divisor is set to 16 */
+#define APIC_DIVISOR 16
+
/*
* This function sets up the local APIC timer, with a timeout of
* 'clocks' APIC bus clock. During calibration we actually call
@@ -197,7 +200,7 @@ static void __setup_APIC_LVTT(unsigned i
| APIC_TDR_DIV_16);

if (!oneshot)
- apic_write(APIC_TMICT, clocks);
+ apic_write(APIC_TMICT, clocks/APIC_DIVISOR);
}

/*
@@ -329,7 +332,7 @@ static void __init calibrate_APIC_clock(
*
* No interrupt enable !
*/
- __setup_APIC_LVTT(250000000, 0, 0);
+ __setup_APIC_LVTT(4000000000, 0, 0);

apic_start = apic_read(APIC_TMCCT);
#ifdef CONFIG_X86_PM_TIMER

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