freebsd-skq/sys/x86/include/pvclock.h
bryanv 7a68cf4e59 Add interface to derive a TSC frequency from the pvclock
This can later use this to determine the TSC frequency like is done with
VMware, instead of using a DELAY loop that is not always accurate in an VM.

MFC after:	1 month
2015-02-04 08:33:04 +00:00

60 lines
2.0 KiB
C

/*-
* Copyright (c) 2014, Bryan Venteicher <bryanv@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef X86_PVCLOCK
#define X86_PVCLOCK
struct pvclock_vcpu_time_info {
uint32_t version;
uint32_t pad0;
uint64_t tsc_timestamp;
uint64_t system_time;
uint32_t tsc_to_system_mul;
int8_t tsc_shift;
uint8_t flags;
uint8_t pad[2];
};
#define PVCLOCK_FLAG_TSC_STABLE 0x01
#define PVCLOCK_FLAG_GUEST_PASUED 0x02
struct pvclock_wall_clock {
uint32_t version;
uint32_t sec;
uint32_t nsec;
};
void pvclock_resume(void);
uint64_t pvclock_get_last_cycles(void);
uint64_t pvclock_tsc_freq(struct pvclock_vcpu_time_info *ti);
uint64_t pvclock_get_timecount(struct pvclock_vcpu_time_info *ti);
void pvclock_get_wallclock(struct pvclock_wall_clock *wc,
struct timespec *ts);
#endif