1 // SPDX-License-Identifier: GPL-2.0+
5 * Copyright (c) 2016 Google, Inc
6 * Written by Simon Glass <sjg@chromium.org>
8 * This program demonstrates calling a boottime service.
9 * It writes a greeting and the load options to the console.
15 static const efi_guid_t loaded_image_guid = LOADED_IMAGE_GUID;
16 static const efi_guid_t fdt_guid = EFI_FDT_GUID;
17 static const efi_guid_t acpi_guid = EFI_ACPI_TABLE_GUID;
18 static const efi_guid_t smbios_guid = SMBIOS_TABLE_GUID;
20 static int hw_memcmp(const void *buf1, const void *buf2, size_t length)
22 const u8 *pos1 = buf1;
23 const u8 *pos2 = buf2;
25 for (; length; --length) {
35 * Entry point of the EFI application.
37 * @handle handle of the loaded image
38 * @systable system table
41 efi_status_t EFIAPI efi_main(efi_handle_t handle,
42 struct efi_system_table *systable)
44 struct efi_simple_text_output_protocol *con_out = systable->con_out;
45 struct efi_boot_services *boottime = systable->boottime;
46 struct efi_loaded_image *loaded_image;
51 con_out->output_string(con_out, L"Hello, world!\n");
53 /* Print the revision number */
54 rev[0] = (systable->hdr.revision >> 16) + '0';
55 rev[4] = systable->hdr.revision & 0xffff;
56 for (; rev[4] >= 10;) {
60 /* Third digit is only to be shown if non-zero */
66 con_out->output_string(con_out, L"Running on UEFI ");
67 con_out->output_string(con_out, rev);
68 con_out->output_string(con_out, L"\n");
70 /* Get the loaded image protocol */
71 ret = boottime->handle_protocol(handle, &loaded_image_guid,
72 (void **)&loaded_image);
73 if (ret != EFI_SUCCESS) {
74 con_out->output_string(con_out,
75 L"Cannot open loaded image protocol\n");
78 /* Find configuration tables */
79 for (i = 0; i < systable->nr_tables; ++i) {
80 if (!hw_memcmp(&systable->tables[i].guid, &fdt_guid,
82 con_out->output_string(con_out, L"Have device tree\n");
83 if (!hw_memcmp(&systable->tables[i].guid, &acpi_guid,
85 con_out->output_string(con_out, L"Have ACPI 2.0 table\n");
86 if (!hw_memcmp(&systable->tables[i].guid, &smbios_guid,
88 con_out->output_string(con_out, L"Have SMBIOS table\n");
90 /* Output the load options */
91 con_out->output_string(con_out, L"Load options: ");
92 if (loaded_image->load_options_size && loaded_image->load_options)
93 con_out->output_string(con_out,
94 (u16 *)loaded_image->load_options);
96 con_out->output_string(con_out, L"<none>");
97 con_out->output_string(con_out, L"\n");
100 boottime->exit(handle, ret, 0, NULL);
102 /* We should never arrive here */