1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * EFI hello world 4 * 5 * Copyright (c) 2016 Google, Inc 6 * Written by Simon Glass <sjg@chromium.org> 7 * 8 * This program demonstrates calling a boottime service. 9 * It writes a greeting and the load options to the console. 10 */ 11 12 #include <common.h> 13 #include <efi_api.h> 14 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; 19 20 /** 21 * efi_main() - entry point of the EFI application. 22 * 23 * @handle: handle of the loaded image 24 * @systable: system table 25 * @return: status code 26 */ 27 efi_status_t EFIAPI efi_main(efi_handle_t handle, 28 struct efi_system_table *systable) 29 { 30 struct efi_simple_text_output_protocol *con_out = systable->con_out; 31 struct efi_boot_services *boottime = systable->boottime; 32 struct efi_loaded_image *loaded_image; 33 efi_status_t ret; 34 efi_uintn_t i; 35 u16 rev[] = L"0.0.0"; 36 37 /* UEFI requires CR LF */ 38 con_out->output_string(con_out, L"Hello, world!\r\n"); 39 40 /* Print the revision number */ 41 rev[0] = (systable->hdr.revision >> 16) + '0'; 42 rev[4] = systable->hdr.revision & 0xffff; 43 for (; rev[4] >= 10;) { 44 rev[4] -= 10; 45 ++rev[2]; 46 } 47 /* Third digit is only to be shown if non-zero */ 48 if (rev[4]) 49 rev[4] += '0'; 50 else 51 rev[3] = 0; 52 53 con_out->output_string(con_out, L"Running on UEFI "); 54 con_out->output_string(con_out, rev); 55 con_out->output_string(con_out, L"\r\n"); 56 57 /* Get the loaded image protocol */ 58 ret = boottime->handle_protocol(handle, &loaded_image_guid, 59 (void **)&loaded_image); 60 if (ret != EFI_SUCCESS) { 61 con_out->output_string 62 (con_out, L"Cannot open loaded image protocol\r\n"); 63 goto out; 64 } 65 /* Find configuration tables */ 66 for (i = 0; i < systable->nr_tables; ++i) { 67 if (!memcmp(&systable->tables[i].guid, &fdt_guid, 68 sizeof(efi_guid_t))) 69 con_out->output_string 70 (con_out, L"Have device tree\r\n"); 71 if (!memcmp(&systable->tables[i].guid, &acpi_guid, 72 sizeof(efi_guid_t))) 73 con_out->output_string 74 (con_out, L"Have ACPI 2.0 table\r\n"); 75 if (!memcmp(&systable->tables[i].guid, &smbios_guid, 76 sizeof(efi_guid_t))) 77 con_out->output_string 78 (con_out, L"Have SMBIOS table\r\n"); 79 } 80 /* Output the load options */ 81 con_out->output_string(con_out, L"Load options: "); 82 if (loaded_image->load_options_size && loaded_image->load_options) 83 con_out->output_string(con_out, 84 (u16 *)loaded_image->load_options); 85 else 86 con_out->output_string(con_out, L"<none>"); 87 con_out->output_string(con_out, L"\r\n"); 88 89 out: 90 boottime->exit(handle, ret, 0, NULL); 91 92 /* We should never arrive here */ 93 return ret; 94 } 95