src/soc/amd/stoneyridge/monotonic_timer.c

   1 /*
   2  * This file is part of the coreboot project.
   3  *
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <cpu/x86/msr.h>
  16 #include <timer.h>
  17 #include <timestamp.h>
  18
  19 #define CU_PTSC_MSR     0xc0010280
  20 #define PTSC_FREQ_MHZ   100
  21
  22 void timer_monotonic_get(struct mono_time *mt)
  23 {
  24         mono_time_set_usecs(mt, timestamp_get());
  25 }
  26
  27 uint64_t timestamp_get(void)
  28 {
  29         unsigned long long val;
  30         msr_t msr;
  31
  32         msr = rdmsr(CU_PTSC_MSR);
  33
  34         val = ((unsigned long long)msr.hi << 32) | msr.lo;
  35
  36         return val / PTSC_FREQ_MHZ;
  37 }