1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2021 Vladimir Kondratyev <wulf@FreeBSD.org> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 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 ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #ifndef _LINUXKPI_LINUX_EFI_H_ 29 #define _LINUXKPI_LINUX_EFI_H_ 30 31 #include <sys/param.h> 32 #include <sys/linker.h> 33 #include <sys/systm.h> 34 35 #include <machine/md_var.h> 36 #include <machine/metadata.h> 37 38 #define EFI_BOOT 0 39 40 static inline bool 41 __efi_enabled(int feature) 42 { 43 #if defined(MODINFOMD_EFI_MAP) && !defined(__amd64__) 44 caddr_t kmdp; 45 #endif 46 bool enabled = false; 47 48 switch (feature) { 49 case EFI_BOOT: 50 #ifdef __amd64__ 51 /* Use cached value on amd64 */ 52 enabled = efi_boot; 53 #elif defined(MODINFOMD_EFI_MAP) 54 kmdp = preload_search_by_type("elf kernel"); 55 if (kmdp == NULL) 56 kmdp = preload_search_by_type("elf64 kernel"); 57 enabled = preload_search_info(kmdp, 58 MODINFO_METADATA | MODINFOMD_EFI_MAP) != NULL; 59 #endif 60 break; 61 default: 62 break; 63 } 64 65 return (enabled); 66 } 67 68 #define efi_enabled(x) ({ \ 69 _Static_assert((x) == EFI_BOOT, "unsupported feature"); \ 70 __efi_enabled(x); \ 71 }) 72 73 #endif /* _LINUXKPI_LINUX_EFI_H_ */ 74