src/cpu/intel/haswell/tsc_freq.c


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/*
 * This file is part of the coreboot project.
 *
 * Copyright (C) 2013 Google, Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <stdint.h>
#include <cpu/x86/msr.h>
#include <cpu/x86/tsc.h>
#include "cpu/intel/haswell/haswell.h"

unsigned long tsc_freq_mhz(void)
{
	msr_t platform_info;

	platform_info = rdmsr(MSR_PLATFORM_INFO);
	return HASWELL_BCLK * ((platform_info.lo >> 8) & 0xff);
}