src/soc/amd/stoneyridge/monotonic_timer.c


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25

/* SPDX-License-Identifier: GPL-2.0-only */

#include <cpu/x86/msr.h>
#include <timer.h>
#include <timestamp.h>

#define CU_PTSC_MSR	0xc0010280
#define PTSC_FREQ_MHZ	100

void timer_monotonic_get(struct mono_time *mt)
{
	mono_time_set_usecs(mt, timestamp_get());
}

uint64_t timestamp_get(void)
{
	unsigned long long val;
	msr_t msr;

	msr = rdmsr(CU_PTSC_MSR);

	val = ((unsigned long long)msr.hi << 32) | msr.lo;

	return val / PTSC_FREQ_MHZ;
}