1*d55ef580Srobert /* $OpenBSD: usertc.c,v 1.5 2022/09/22 04:57:07 robert Exp $ */
2d82e6535Spirofti /*
3d82e6535Spirofti * Copyright (c) 2020 Paul Irofti <paul@irofti.net>
4d82e6535Spirofti *
5d82e6535Spirofti * Permission to use, copy, modify, and distribute this software for any
6d82e6535Spirofti * purpose with or without fee is hereby granted, provided that the above
7d82e6535Spirofti * copyright notice and this permission notice appear in all copies.
8d82e6535Spirofti *
9d82e6535Spirofti * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10d82e6535Spirofti * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11d82e6535Spirofti * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12d82e6535Spirofti * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13d82e6535Spirofti * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14d82e6535Spirofti * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15d82e6535Spirofti * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16d82e6535Spirofti */
17d82e6535Spirofti
18d82e6535Spirofti #include <sys/types.h>
19d82e6535Spirofti #include <sys/timetc.h>
20d82e6535Spirofti
21d82e6535Spirofti static inline u_int
rdtsc_lfence(void)22ce9a4ac3Scheloha rdtsc_lfence(void)
23d82e6535Spirofti {
24d82e6535Spirofti uint32_t hi, lo;
2578617c59Sjca __asm volatile("lfence; rdtsc" : "=a"(lo), "=d"(hi));
26d82e6535Spirofti return ((uint64_t)lo)|(((uint64_t)hi)<<32);
27d82e6535Spirofti }
28d82e6535Spirofti
29*d55ef580Srobert static inline u_int
rdtscp(void)30*d55ef580Srobert rdtscp(void)
31*d55ef580Srobert {
32*d55ef580Srobert uint32_t hi, lo;
33*d55ef580Srobert __asm volatile("rdtscp" : "=a"(lo), "=d"(hi) : : "ecx");
34*d55ef580Srobert return ((uint64_t)lo)|(((uint64_t)hi)<<32);
35*d55ef580Srobert }
36*d55ef580Srobert
37c8437fb9Skettenis static int
tc_get_timecount(struct timekeep * tk,u_int * tc)38d82e6535Spirofti tc_get_timecount(struct timekeep *tk, u_int *tc)
39d82e6535Spirofti {
40c8437fb9Skettenis switch (tk->tk_user) {
41*d55ef580Srobert case TC_TSC_LFENCE:
42ce9a4ac3Scheloha *tc = rdtsc_lfence();
43d82e6535Spirofti return 0;
44*d55ef580Srobert case TC_TSC_RDTSCP:
45*d55ef580Srobert *tc = rdtscp();
46*d55ef580Srobert return 0;
47d82e6535Spirofti }
48c8437fb9Skettenis
49c8437fb9Skettenis return -1;
50c8437fb9Skettenis }
51c8437fb9Skettenis
52c8437fb9Skettenis int (*const _tc_get_timecount)(struct timekeep *, u_int *) = tc_get_timecount;
53