diff options
Diffstat (limited to 'roms/u-boot/lib/efi_loader/efi_bootmgr.c')
| -rw-r--r-- | roms/u-boot/lib/efi_loader/efi_bootmgr.c | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/roms/u-boot/lib/efi_loader/efi_bootmgr.c b/roms/u-boot/lib/efi_loader/efi_bootmgr.c new file mode 100644 index 000000000..1fe19237f --- /dev/null +++ b/roms/u-boot/lib/efi_loader/efi_bootmgr.c @@ -0,0 +1,201 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * EFI boot manager + * + * Copyright (c) 2017 Rob Clark + */ + +#define LOG_CATEGORY LOGC_EFI + +#include <common.h> +#include <charset.h> +#include <log.h> +#include <malloc.h> +#include <efi_loader.h> +#include <efi_variable.h> +#include <asm/unaligned.h> + +static const struct efi_boot_services *bs; +static const struct efi_runtime_services *rs; + +/* + * bootmgr implements the logic of trying to find a payload to boot + * based on the BootOrder + BootXXXX variables, and then loading it. + * + * TODO detecting a special key held (f9?) and displaying a boot menu + * like you would get on a PC would be clever. + * + * TODO if we had a way to write and persist variables after the OS + * has started, we'd also want to check OsIndications to see if we + * should do normal or recovery boot. + */ + +/** + * try_load_entry() - try to load image for boot option + * + * Attempt to load load-option number 'n', returning device_path and file_path + * if successful. This checks that the EFI_LOAD_OPTION is active (enabled) + * and that the specified file to boot exists. + * + * @n: number of the boot option, e.g. 0x0a13 for Boot0A13 + * @handle: on return handle for the newly installed image + * @load_options: load options set on the loaded image protocol + * Return: status code + */ +static efi_status_t try_load_entry(u16 n, efi_handle_t *handle, + void **load_options) +{ + struct efi_load_option lo; + u16 varname[] = L"Boot0000"; + u16 hexmap[] = L"0123456789ABCDEF"; + void *load_option; + efi_uintn_t size; + efi_status_t ret; + + varname[4] = hexmap[(n & 0xf000) >> 12]; + varname[5] = hexmap[(n & 0x0f00) >> 8]; + varname[6] = hexmap[(n & 0x00f0) >> 4]; + varname[7] = hexmap[(n & 0x000f) >> 0]; + + load_option = efi_get_var(varname, &efi_global_variable_guid, &size); + if (!load_option) + return EFI_LOAD_ERROR; + + ret = efi_deserialize_load_option(&lo, load_option, &size); + if (ret != EFI_SUCCESS) { + log_warning("Invalid load option for %ls\n", varname); + goto error; + } + + if (lo.attributes & LOAD_OPTION_ACTIVE) { + u32 attributes; + + log_debug("%s: trying to load \"%ls\" from %pD\n", + __func__, lo.label, lo.file_path); + + ret = EFI_CALL(efi_load_image(true, efi_root, lo.file_path, + NULL, 0, handle)); + if (ret != EFI_SUCCESS) { + log_warning("Loading %ls '%ls' failed\n", + varname, lo.label); + goto error; + } + + attributes = EFI_VARIABLE_BOOTSERVICE_ACCESS | + EFI_VARIABLE_RUNTIME_ACCESS; + ret = efi_set_variable_int(L"BootCurrent", + &efi_global_variable_guid, + attributes, sizeof(n), &n, false); + if (ret != EFI_SUCCESS) + goto unload; + /* try to register load file2 for initrd's */ + if (IS_ENABLED(CONFIG_EFI_LOAD_FILE2_INITRD)) { + ret = efi_initrd_register(); + if (ret != EFI_SUCCESS) + goto unload; + } + + log_info("Booting: %ls\n", lo.label); + } else { + ret = EFI_LOAD_ERROR; + } + + /* Set load options */ + if (size) { + *load_options = malloc(size); + if (!*load_options) { + ret = EFI_OUT_OF_RESOURCES; + goto error; + } + memcpy(*load_options, lo.optional_data, size); + ret = efi_set_load_options(*handle, size, *load_options); + } else { + *load_options = NULL; + } + +error: + free(load_option); + + return ret; + +unload: + if (EFI_CALL(efi_unload_image(*handle)) != EFI_SUCCESS) + log_err("Unloading image failed\n"); + free(load_option); + + return ret; +} + +/** + * efi_bootmgr_load() - try to load from BootNext or BootOrder + * + * Attempt to load from BootNext or in the order specified by BootOrder + * EFI variable, the available load-options, finding and returning + * the first one that can be loaded successfully. + * + * @handle: on return handle for the newly installed image + * @load_options: load options set on the loaded image protocol + * Return: status code + */ +efi_status_t efi_bootmgr_load(efi_handle_t *handle, void **load_options) +{ + u16 bootnext, *bootorder; + efi_uintn_t size; + int i, num; + efi_status_t ret; + + bs = systab.boottime; + rs = systab.runtime; + + /* BootNext */ + size = sizeof(bootnext); + ret = efi_get_variable_int(L"BootNext", + &efi_global_variable_guid, + NULL, &size, &bootnext, NULL); + if (ret == EFI_SUCCESS || ret == EFI_BUFFER_TOO_SMALL) { + /* BootNext does exist here */ + if (ret == EFI_BUFFER_TOO_SMALL || size != sizeof(u16)) + log_err("BootNext must be 16-bit integer\n"); + + /* delete BootNext */ + ret = efi_set_variable_int(L"BootNext", + &efi_global_variable_guid, + 0, 0, NULL, false); + + /* load BootNext */ + if (ret == EFI_SUCCESS) { + if (size == sizeof(u16)) { + ret = try_load_entry(bootnext, handle, + load_options); + if (ret == EFI_SUCCESS) + return ret; + log_warning( + "Loading from BootNext failed, falling back to BootOrder\n"); + } + } else { + log_err("Deleting BootNext failed\n"); + } + } + + /* BootOrder */ + bootorder = efi_get_var(L"BootOrder", &efi_global_variable_guid, &size); + if (!bootorder) { + log_info("BootOrder not defined\n"); + ret = EFI_NOT_FOUND; + goto error; + } + + num = size / sizeof(uint16_t); + for (i = 0; i < num; i++) { + log_debug("%s trying to load Boot%04X\n", __func__, + bootorder[i]); + ret = try_load_entry(bootorder[i], handle, load_options); + if (ret == EFI_SUCCESS) + break; + } + + free(bootorder); + +error: + return ret; +} |