1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2013 The NetBSD Foundation, Inc. 5 * Copyright (c) 2013 Andrew Turner 6 * All rights reserved. 7 * 8 * This code is derived from software contributed to The NetBSD Foundation 9 * by Matt Thomas of 3am Software Foundry. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 * 32 * Bases on NetBSD lib/libc/arch/arm/misc/arm_initfini.c 33 * $NetBSD: arm_initfini.c,v 1.2 2013/01/31 06:47:55 matt Exp $ 34 */ 35 36 #include <sys/cdefs.h> 37 /* 38 * To properly implement setjmp/longjmp for the ARM AAPCS ABI, it has to be 39 * aware of whether there is a FPU is present or not. Regardless of whether 40 * the hard-float ABI is being used, setjmp needs to save D8-D15. But it can 41 * only do this if those instructions won't cause an exception. 42 */ 43 44 #include <sys/param.h> 45 #include <sys/sysctl.h> 46 47 #include <stdbool.h> 48 #include <stddef.h> 49 50 extern int __sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, 51 void *newp, size_t newlen); 52 53 int _libc_arm_fpu_present; 54 static bool _libc_aapcs_initialized; 55 56 void _libc_aapcs_init(void) __attribute__((__constructor__, __used__)); 57 58 void 59 _libc_aapcs_init(void) 60 { 61 int mib[2]; 62 size_t len; 63 64 if (_libc_aapcs_initialized) 65 return; 66 67 mib[0] = CTL_HW; 68 mib[1] = HW_FLOATINGPT; 69 70 len = sizeof(_libc_arm_fpu_present); 71 if (__sysctl(mib, 2, &_libc_arm_fpu_present, &len, NULL, 0) == -1 || 72 len != sizeof(_libc_arm_fpu_present)) { 73 /* sysctl failed, assume no vfp */ 74 _libc_arm_fpu_present = 0; 75 } 76 77 _libc_aapcs_initialized = true; 78 } 79