[PATCH] x86-64: fix cpu MHz reporting on constant_tsc cpus

This patch fixes the reporting of cpu_mhz in /proc/cpuinfo on CPUs with
a constant TSC rate and a kernel with disabled cpufreq.

Signed-off-by: Mark Langsdorf <mark.langsdorf@amd.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Andi Kleen <ak@suse.de>

 arch/x86_64/kernel/apic.c     |    2 -
 arch/x86_64/kernel/time.c     |   58 +++++++++++++++++++++++++++++++++++++++---
 arch/x86_64/kernel/tsc.c      |   12 +++++---
 arch/x86_64/kernel/tsc_sync.c |    2 -
 include/asm-x86_64/proto.h    |    1
 5 files changed, 65 insertions(+), 10 deletions(-)
diff --git a/include/asm-x86_64/proto.h b/include/asm-x86_64/proto.h
index f64949f..7842702 100644
--- a/include/asm-x86_64/proto.h
+++ b/include/asm-x86_64/proto.h
@@ -92,6 +92,7 @@
 
 extern int exception_trace;
 extern unsigned cpu_khz;
+extern unsigned tsc_khz;
 
 extern void no_iommu_init(void);
 extern int force_iommu, no_iommu;