xref: /openbmc/u-boot/lib/efi_loader/efi_smbios.c (revision 90c08fa0)
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 	if (ret != EFI_SUCCESS)
30 		return ret;
31 
32 	/*
33 	 * Generate SMBIOS tables - we know that efi_allocate_pages() returns
34 	 * a 4k-aligned address, so it is safe to assume that
35 	 * write_smbios_table() will write the table at that address.
36 	 */
37 	assert(!(dmi & 0xf));
38 	write_smbios_table(dmi);
39 
40 	/* And expose them to our EFI payload */
41 	return efi_install_configuration_table(&smbios_guid,
42 					       (void *)(uintptr_t)dmi);
43 }
44