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/* 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());
}
/* The TSC has a non-constant rate before the microcode update is applied, so it can't be used
in timestamp_get before that. Instead, the Performance Time Stamp Counter is used. */
uint64_t timestamp_get(void)
{
msr_t msr;
msr = rdmsr(CU_PTSC_MSR);
return msr.raw / PTSC_FREQ_MHZ;
}
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