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 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 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 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 69 __vdso_gettimekeep(struct vdso_timekeep **tk) 70 { 71 72 return (_elf_aux_info(AT_TIMEKEEP, tk, sizeof(*tk))); 73 } 74