1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * EFI application tables support 4 * 5 * Copyright (c) 2016 Alexander Graf 6 */ 7 8 #include <common.h> 9 #include <efi_loader.h> 10 #include <smbios.h> 11 12 static const efi_guid_t smbios_guid = SMBIOS_TABLE_GUID; 13 14 /* 15 * Install the SMBIOS table as a configuration table. 16 * 17 * @return status code 18 */ 19 efi_status_t efi_smbios_register(void) 20 { 21 /* Map within the low 32 bits, to allow for 32bit SMBIOS tables */ 22 u64 dmi = U32_MAX; 23 efi_status_t ret; 24 25 /* Reserve 4kiB page for SMBIOS */ 26 ret = efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS, 27 EFI_RUNTIME_SERVICES_DATA, 1, &dmi); 28 29 if (ret != EFI_SUCCESS) { 30 /* Could not find space in lowmem, use highmem instead */ 31 ret = efi_allocate_pages(EFI_ALLOCATE_ANY_PAGES, 32 EFI_RUNTIME_SERVICES_DATA, 1, &dmi); 33 34 if (ret != EFI_SUCCESS) 35 return ret; 36 } 37 38 /* 39 * Generate SMBIOS tables - we know that efi_allocate_pages() returns 40 * a 4k-aligned address, so it is safe to assume that 41 * write_smbios_table() will write the table at that address. 42 */ 43 assert(!(dmi & 0xf)); 44 write_smbios_table(dmi); 45 46 /* And expose them to our EFI payload */ 47 return efi_install_configuration_table(&smbios_guid, 48 (void *)(uintptr_t)dmi); 49 } 50