1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2015 The FreeBSD Foundation 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 #include <machine/cpufunc.h> 36 #include <machine/acle-compat.h> 37 #include <errno.h> 38 #include "libc_private.h" 39 40 #if __ARM_ARCH >= 6 41 static inline uint64_t 42 cp15_cntvct_get(void) 43 { 44 uint64_t reg; 45 46 __asm __volatile("mrrc\tp15, 1, %Q0, %R0, c14" : "=r" (reg)); 47 return (reg); 48 } 49 50 static inline uint64_t 51 cp15_cntpct_get(void) 52 { 53 uint64_t reg; 54 55 __asm __volatile("mrrc\tp15, 0, %Q0, %R0, c14" : "=r" (reg)); 56 return (reg); 57 } 58 #endif 59 60 #pragma weak __vdso_gettc 61 int 62 __vdso_gettc(const struct vdso_timehands *th, u_int *tc) 63 { 64 65 if (th->th_algo != VDSO_TH_ALGO_ARM_GENTIM) 66 return (ENOSYS); 67 #if __ARM_ARCH >= 6 68 /* 69 * Userspace gettimeofday() is only enabled on ARMv7 CPUs, but 70 * libc is compiled for ARMv6. Due to clang issues, .arch 71 * armv7-a directive does not work. 72 */ 73 __asm __volatile(".word\t0xf57ff06f" : : : "memory"); /* isb */ 74 *tc = th->th_physical == 0 ? cp15_cntvct_get() : cp15_cntpct_get(); 75 return (0); 76 #else 77 *tc = 0; 78 return (ENOSYS); 79 #endif 80 } 81 82 #pragma weak __vdso_gettimekeep 83 int 84 __vdso_gettimekeep(struct vdso_timekeep **tk) 85 { 86 87 return (_elf_aux_info(AT_TIMEKEEP, tk, sizeof(*tk))); 88 } 89