src/soc/intel/broadwell/tsc_freq.c

   1 /*
   2  * This file is part of the coreboot project.
   3  *
   4  * Copyright (C) 2014 Google Inc.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; version 2 of the License.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #include <stdint.h>
  17 #include <cpu/x86/msr.h>
  18 #include <cpu/x86/tsc.h>
  19 #include <soc/cpu.h>
  20 #include <soc/msr.h>
  21
  22 unsigned long tsc_freq_mhz(void)
  23 {
  24         msr_t platform_info;
  25
  26         platform_info = rdmsr(MSR_PLATFORM_INFO);
  27         return CPU_BCLK * ((platform_info.lo >> 8) & 0xff);
  28 }