[PATCH] x86_64: remove check for CONSTANT_TSC from time.c

From: Joerg Roedel
Date: Mon Jun 04 2007 - 14:10:00 EST


From: Joerg Roedel <joerg.roedel@xxxxxxx>

This patch removes the check for the CONSTANT_TSC cpu flag from time.c
on the x86_64 architecture. At the time this flag is checked at boot the
cpu init code was yet not executed and thus the check fails. At this
point the check for VENDOR_AMD and cpu family 0x10 is sufficient.

Signed-off-by: Joerg Roedel <joerg.roedel@xxxxxxx>

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diff --git a/arch/x86_64/kernel/time.c b/arch/x86_64/kernel/time.c
index 4a0895b..8b29928 100644
--- a/arch/x86_64/kernel/time.c
+++ b/arch/x86_64/kernel/time.c
@@ -394,9 +394,9 @@ void __init time_init(void)
}

cpu_khz = tsc_khz;
- if (cpu_has(&boot_cpu_data, X86_FEATURE_CONSTANT_TSC) &&
- boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
boot_cpu_data.x86 == 16)
+ /* AMD Family 0x10 processors have a constant tsc */
cpu_khz = tsc_calibrate_cpu_khz();

if (unsynchronized_tsc())