1 // SPDX-License-Identifier: GPL-2.0+
3 * EFI application tables support
5 * Copyright (c) 2016 Alexander Graf
9 #include <efi_loader.h>
13 static const efi_guid_t smbios_guid = SMBIOS_TABLE_GUID;
16 * Install the SMBIOS table as a configuration table.
20 efi_status_t efi_smbios_register(void)
22 /* Map within the low 32 bits, to allow for 32bit SMBIOS tables */
23 u64 dmi_addr = U32_MAX;
27 /* Reserve 4kiB page for SMBIOS */
28 ret = efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
29 EFI_RUNTIME_SERVICES_DATA, 1, &dmi_addr);
31 if (ret != EFI_SUCCESS) {
32 /* Could not find space in lowmem, use highmem instead */
33 ret = efi_allocate_pages(EFI_ALLOCATE_ANY_PAGES,
34 EFI_RUNTIME_SERVICES_DATA, 1,
37 if (ret != EFI_SUCCESS)
42 * Generate SMBIOS tables - we know that efi_allocate_pages() returns
43 * a 4k-aligned address, so it is safe to assume that
44 * write_smbios_table() will write the table at that address.
46 * Note that on sandbox, efi_allocate_pages() unfortunately returns a
47 * pointer even though it uses a uint64_t type. Convert it.
49 assert(!(dmi_addr & 0xf));
50 dmi = (void *)(uintptr_t)dmi_addr;
51 write_smbios_table(map_to_sysmem(dmi));
53 /* And expose them to our EFI payload */
54 return efi_install_configuration_table(&smbios_guid, dmi);