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 <inttypes.h> 11 #include <smbios.h> 12 13 static const efi_guid_t smbios_guid = SMBIOS_TABLE_GUID; 14 15 /* 16 * Install the SMBIOS table as a configuration table. 17 * 18 * @return status code 19 */ 20 efi_status_t efi_smbios_register(void) 21 { 22 /* Map within the low 32 bits, to allow for 32bit SMBIOS tables */ 23 u64 dmi = U32_MAX; 24 efi_status_t ret; 25 26 /* Reserve 4kiB page for SMBIOS */ 27 ret = efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS, 28 EFI_RUNTIME_SERVICES_DATA, 1, &dmi); 29 30 if (ret != EFI_SUCCESS) { 31 /* Could not find space in lowmem, use highmem instead */ 32 ret = efi_allocate_pages(EFI_ALLOCATE_ANY_PAGES, 33 EFI_RUNTIME_SERVICES_DATA, 1, &dmi); 34 35 if (ret != EFI_SUCCESS) 36 return ret; 37 } 38 39 /* 40 * Generate SMBIOS tables - we know that efi_allocate_pages() returns 41 * a 4k-aligned address, so it is safe to assume that 42 * write_smbios_table() will write the table at that address. 43 */ 44 assert(!(dmi & 0xf)); 45 write_smbios_table(dmi); 46 47 /* And expose them to our EFI payload */ 48 return efi_install_configuration_table(&smbios_guid, 49 (void *)(uintptr_t)dmi); 50 } 51