xref: /freebsd/lib/libsys/powerpc64/__vdso_gettc.c (revision 1edb7116)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2020 Brandon Bergren <bdragon@FreeBSD.org>
5  *
6  * This software was developed by Konstantin Belousov
7  * under sponsorship from the FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/types.h>
32 #include <sys/elf.h>
33 #include <sys/time.h>
34 #include <sys/vdso.h>
35 
36 #include <machine/cpufunc.h>
37 
38 #include <errno.h>
39 
40 #include "libc_private.h"
41 
42 #pragma weak __vdso_gettc
43 int
44 __vdso_gettc(const struct vdso_timehands *th, u_int *tc)
45 {
46 	u_quad_t tb;
47 
48 	if (__predict_false(th->th_algo != VDSO_TH_ALGO_PPC_TB))
49 		return (ENOSYS);
50 
51 	__asm __volatile ("mftb %0" : "=r"(tb));
52 	*tc = tb;
53 	return (0);
54 }
55 
56 #pragma weak __vdso_gettimekeep
57 int
58 __vdso_gettimekeep(struct vdso_timekeep **tk)
59 {
60 
61 	return (_elf_aux_info(AT_TIMEKEEP, tk, sizeof(*tk)));
62 }
63