1 /*-
2 * Copyright (c) 2015 The FreeBSD Foundation
3 *
4 * This software was developed by Konstantin Belousov
5 * under sponsorship from the FreeBSD Foundation.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/types.h>
30 #include <sys/elf.h>
31 #include <sys/time.h>
32 #include <sys/vdso.h>
33 #include <machine/cpufunc.h>
34 #include <errno.h>
35 #include "libc_private.h"
36
37 static inline uint64_t
cp15_cntvct_get(void)38 cp15_cntvct_get(void)
39 {
40 uint64_t reg;
41
42 __asm __volatile("mrs %0, cntvct_el0" : "=r" (reg));
43 return (reg);
44 }
45
46 static inline uint64_t
cp15_cntpct_get(void)47 cp15_cntpct_get(void)
48 {
49 uint64_t reg;
50
51 __asm __volatile("mrs %0, cntpct_el0" : "=r" (reg));
52 return (reg);
53 }
54
55 #pragma weak __vdso_gettc
56 int
__vdso_gettc(const struct vdso_timehands * th,u_int * tc)57 __vdso_gettc(const struct vdso_timehands *th, u_int *tc)
58 {
59
60 if (th->th_algo != VDSO_TH_ALGO_ARM_GENTIM)
61 return (ENOSYS);
62 __asm __volatile("isb" : : : "memory");
63 *tc = th->th_physical == 0 ? cp15_cntvct_get() : cp15_cntpct_get();
64 return (0);
65 }
66
67 #pragma weak __vdso_gettimekeep
68 int
__vdso_gettimekeep(struct vdso_timekeep ** tk)69 __vdso_gettimekeep(struct vdso_timekeep **tk)
70 {
71
72 return (_elf_aux_info(AT_TIMEKEEP, tk, sizeof(*tk)));
73 }
74