183d290c5STom Rini // SPDX-License-Identifier: GPL-2.0+ 2c7ae3dfdSSimon Glass /* 3c7ae3dfdSSimon Glass * EFI hello world 4c7ae3dfdSSimon Glass * 5c7ae3dfdSSimon Glass * Copyright (c) 2016 Google, Inc 6c7ae3dfdSSimon Glass * Written by Simon Glass <sjg@chromium.org> 7c7ae3dfdSSimon Glass * 8bbf75dd9SHeinrich Schuchardt * This program demonstrates calling a boottime service. 9bbf75dd9SHeinrich Schuchardt * It writes a greeting and the load options to the console. 10c7ae3dfdSSimon Glass */ 11c7ae3dfdSSimon Glass 12c7ae3dfdSSimon Glass #include <common.h> 13c7ae3dfdSSimon Glass #include <efi_api.h> 14c7ae3dfdSSimon Glass 15ae67dca5SAlexander Graf static const efi_guid_t loaded_image_guid = LOADED_IMAGE_GUID; 160aaabbb2SHeinrich Schuchardt static const efi_guid_t fdt_guid = EFI_FDT_GUID; 1747cae019SBin Meng static const efi_guid_t acpi_guid = EFI_ACPI_TABLE_GUID; 180aaabbb2SHeinrich Schuchardt static const efi_guid_t smbios_guid = SMBIOS_TABLE_GUID; 190aaabbb2SHeinrich Schuchardt 20*87fc275cSHeinrich Schuchardt /** 21*87fc275cSHeinrich Schuchardt * hw_memcmp() - compare memory areas 22*87fc275cSHeinrich Schuchardt * 23*87fc275cSHeinrich Schuchardt * @buf1: pointer to first area 24*87fc275cSHeinrich Schuchardt * @buf2: pointer to second area 25*87fc275cSHeinrich Schuchardt * @length: number of bytes to compare 26*87fc275cSHeinrich Schuchardt * Return: 0 if both memory areas are the same, otherwise the sign of the 27*87fc275cSHeinrich Schuchardt * result value is the same as the sign of ghe difference between 28*87fc275cSHeinrich Schuchardt * the first differing pair of bytes taken as u8. 29*87fc275cSHeinrich Schuchardt */ 300aaabbb2SHeinrich Schuchardt static int hw_memcmp(const void *buf1, const void *buf2, size_t length) 310aaabbb2SHeinrich Schuchardt { 320aaabbb2SHeinrich Schuchardt const u8 *pos1 = buf1; 330aaabbb2SHeinrich Schuchardt const u8 *pos2 = buf2; 340aaabbb2SHeinrich Schuchardt 350aaabbb2SHeinrich Schuchardt for (; length; --length) { 360aaabbb2SHeinrich Schuchardt if (*pos1 != *pos2) 370aaabbb2SHeinrich Schuchardt return *pos1 - *pos2; 380aaabbb2SHeinrich Schuchardt ++pos1; 390aaabbb2SHeinrich Schuchardt ++pos2; 400aaabbb2SHeinrich Schuchardt } 410aaabbb2SHeinrich Schuchardt return 0; 420aaabbb2SHeinrich Schuchardt } 43ae67dca5SAlexander Graf 44*87fc275cSHeinrich Schuchardt /** 45*87fc275cSHeinrich Schuchardt * efi_main() - entry point of the EFI application. 46bbf75dd9SHeinrich Schuchardt * 47*87fc275cSHeinrich Schuchardt * @handle: handle of the loaded image 48*87fc275cSHeinrich Schuchardt * @systable: system table 49*87fc275cSHeinrich Schuchardt * @return: status code 50bbf75dd9SHeinrich Schuchardt */ 51c7ae3dfdSSimon Glass efi_status_t EFIAPI efi_main(efi_handle_t handle, 52c7ae3dfdSSimon Glass struct efi_system_table *systable) 53c7ae3dfdSSimon Glass { 54c7ae3dfdSSimon Glass struct efi_simple_text_output_protocol *con_out = systable->con_out; 55c7ae3dfdSSimon Glass struct efi_boot_services *boottime = systable->boottime; 56bbf75dd9SHeinrich Schuchardt struct efi_loaded_image *loaded_image; 57bbf75dd9SHeinrich Schuchardt efi_status_t ret; 580aaabbb2SHeinrich Schuchardt efi_uintn_t i; 59f7c342f4SHeinrich Schuchardt u16 rev[] = L"0.0.0"; 60c7ae3dfdSSimon Glass 61*87fc275cSHeinrich Schuchardt /* UEFI requires CR LF */ 62*87fc275cSHeinrich Schuchardt con_out->output_string(con_out, L"Hello, world!\r\n"); 63c7ae3dfdSSimon Glass 64f7c342f4SHeinrich Schuchardt /* Print the revision number */ 65f7c342f4SHeinrich Schuchardt rev[0] = (systable->hdr.revision >> 16) + '0'; 66f7c342f4SHeinrich Schuchardt rev[4] = systable->hdr.revision & 0xffff; 67f7c342f4SHeinrich Schuchardt for (; rev[4] >= 10;) { 68f7c342f4SHeinrich Schuchardt rev[4] -= 10; 69f7c342f4SHeinrich Schuchardt ++rev[2]; 70f7c342f4SHeinrich Schuchardt } 71f7c342f4SHeinrich Schuchardt /* Third digit is only to be shown if non-zero */ 72f7c342f4SHeinrich Schuchardt if (rev[4]) 73f7c342f4SHeinrich Schuchardt rev[4] += '0'; 74f7c342f4SHeinrich Schuchardt else 75f7c342f4SHeinrich Schuchardt rev[3] = 0; 76f7c342f4SHeinrich Schuchardt 77f7c342f4SHeinrich Schuchardt con_out->output_string(con_out, L"Running on UEFI "); 78f7c342f4SHeinrich Schuchardt con_out->output_string(con_out, rev); 79*87fc275cSHeinrich Schuchardt con_out->output_string(con_out, L"\r\n"); 80f7c342f4SHeinrich Schuchardt 81bbf75dd9SHeinrich Schuchardt /* Get the loaded image protocol */ 82bbf75dd9SHeinrich Schuchardt ret = boottime->handle_protocol(handle, &loaded_image_guid, 83bbf75dd9SHeinrich Schuchardt (void **)&loaded_image); 84bbf75dd9SHeinrich Schuchardt if (ret != EFI_SUCCESS) { 85*87fc275cSHeinrich Schuchardt con_out->output_string 86*87fc275cSHeinrich Schuchardt (con_out, L"Cannot open loaded image protocol\r\n"); 87bbf75dd9SHeinrich Schuchardt goto out; 88bbf75dd9SHeinrich Schuchardt } 890aaabbb2SHeinrich Schuchardt /* Find configuration tables */ 900aaabbb2SHeinrich Schuchardt for (i = 0; i < systable->nr_tables; ++i) { 910aaabbb2SHeinrich Schuchardt if (!hw_memcmp(&systable->tables[i].guid, &fdt_guid, 920aaabbb2SHeinrich Schuchardt sizeof(efi_guid_t))) 93*87fc275cSHeinrich Schuchardt con_out->output_string 94*87fc275cSHeinrich Schuchardt (con_out, L"Have device tree\r\n"); 9547cae019SBin Meng if (!hw_memcmp(&systable->tables[i].guid, &acpi_guid, 9647cae019SBin Meng sizeof(efi_guid_t))) 97*87fc275cSHeinrich Schuchardt con_out->output_string 98*87fc275cSHeinrich Schuchardt (con_out, L"Have ACPI 2.0 table\r\n"); 990aaabbb2SHeinrich Schuchardt if (!hw_memcmp(&systable->tables[i].guid, &smbios_guid, 1000aaabbb2SHeinrich Schuchardt sizeof(efi_guid_t))) 101*87fc275cSHeinrich Schuchardt con_out->output_string 102*87fc275cSHeinrich Schuchardt (con_out, L"Have SMBIOS table\r\n"); 1030aaabbb2SHeinrich Schuchardt } 104bbf75dd9SHeinrich Schuchardt /* Output the load options */ 105bbf75dd9SHeinrich Schuchardt con_out->output_string(con_out, L"Load options: "); 106bbf75dd9SHeinrich Schuchardt if (loaded_image->load_options_size && loaded_image->load_options) 107bbf75dd9SHeinrich Schuchardt con_out->output_string(con_out, 108bbf75dd9SHeinrich Schuchardt (u16 *)loaded_image->load_options); 109bbf75dd9SHeinrich Schuchardt else 110bbf75dd9SHeinrich Schuchardt con_out->output_string(con_out, L"<none>"); 111*87fc275cSHeinrich Schuchardt con_out->output_string(con_out, L"\r\n"); 112bbf75dd9SHeinrich Schuchardt 113bbf75dd9SHeinrich Schuchardt out: 114bbf75dd9SHeinrich Schuchardt boottime->exit(handle, ret, 0, NULL); 115bbf75dd9SHeinrich Schuchardt 116bbf75dd9SHeinrich Schuchardt /* We should never arrive here */ 117bbf75dd9SHeinrich Schuchardt return ret; 118c7ae3dfdSSimon Glass } 119