1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2012 Konstantin Belousov <kib@FreeBSD.org> 5 * Copyright (c) 2021 Dmitry Chagin <dchagin@FreeBSD.org> 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 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include <sys/elf.h> 34 #include <sys/errno.h> 35 #include <sys/proc.h> 36 #include <sys/stddef.h> 37 #define _KERNEL 38 #include <sys/vdso.h> 39 #undef _KERNEL 40 #include <stdbool.h> 41 #include <strings.h> 42 43 #include <machine/atomic.h> 44 #include <machine/stdarg.h> 45 46 #include <arm64/linux/linux.h> 47 #include <arm64/linux/linux_syscall.h> 48 #include <compat/linux/linux_errno.h> 49 #include <compat/linux/linux_timer.h> 50 51 /* The kernel fixup this at vDSO install */ 52 uintptr_t *kern_timekeep_base = NULL; 53 uint32_t kern_tsc_selector = 0; 54 55 static int 56 write(int lfd, const void *lbuf, size_t lsize) 57 { 58 register long svc asm("x8") = LINUX_SYS_write; 59 register int fd asm("x0") = lfd; 60 register const char *buf asm("x1") = lbuf; 61 register long size asm("x2") = lsize; 62 register long res asm ("x0"); 63 64 asm volatile( 65 " svc #0\n" 66 : "=r" (res) 67 : "r" (fd), "r" (buf), "r" (size), "r" (svc) 68 : "memory"); 69 return (res); 70 } 71 72 static int 73 __vdso_clock_gettime_fallback(clockid_t clock_id, struct l_timespec *lts) 74 { 75 register long svc asm("x8") = LINUX_SYS_linux_clock_gettime; 76 register clockid_t clockid asm("x0") = clock_id; 77 register struct l_timespec *ts asm("x1") = lts; 78 register long res asm ("x0"); 79 80 asm volatile( 81 " svc #0\n" 82 : "=r" (res) 83 : "r" (clockid), "r" (ts), "r" (svc) 84 : "memory"); 85 return (res); 86 } 87 88 static int 89 __vdso_gettimeofday_fallback(l_timeval *ltv, struct timezone *ltz) 90 { 91 register long svc asm("x8") = LINUX_SYS_gettimeofday; 92 register l_timeval *tv asm("x0") = ltv; 93 register struct timezone *tz asm("x1") = ltz; 94 register long res asm ("x0"); 95 96 asm volatile( 97 " svc #0\n" 98 : "=r" (res) 99 : "r" (tv), "r" (tz), "r" (svc) 100 : "memory"); 101 return (res); 102 } 103 104 static int 105 __vdso_clock_getres_fallback(clockid_t clock_id, struct l_timespec *lts) 106 { 107 register long svc asm("x8") = LINUX_SYS_linux_clock_getres; 108 register clockid_t clockid asm("x0") = clock_id; 109 register struct l_timespec *ts asm("x1") = lts; 110 register long res asm ("x0"); 111 112 asm volatile( 113 " svc #0\n" 114 : "=r" (res) 115 : "r" (clockid), "r" (ts), "r" (svc) 116 : "memory"); 117 return (res); 118 } 119 120 /* 121 * copied from lib/libc/aarch64/sys/__vdso_gettc.c 122 */ 123 124 static inline uint64_t 125 cp15_cntvct_get(void) 126 { 127 uint64_t reg; 128 129 __asm __volatile("mrs %0, cntvct_el0" : "=r" (reg)); 130 return (reg); 131 } 132 133 static inline uint64_t 134 cp15_cntpct_get(void) 135 { 136 uint64_t reg; 137 138 __asm __volatile("mrs %0, cntpct_el0" : "=r" (reg)); 139 return (reg); 140 } 141 142 int 143 __vdso_gettc(const struct vdso_timehands *th, u_int *tc) 144 { 145 146 if (th->th_algo != VDSO_TH_ALGO_ARM_GENTIM) 147 return (ENOSYS); 148 __asm __volatile("isb" : : : "memory"); 149 *tc = th->th_physical == 0 ? cp15_cntvct_get() : cp15_cntpct_get(); 150 return (0); 151 } 152 153 #include <compat/linux/linux_vdso_gtod.inc> 154