diff options
Diffstat (limited to 'lib/efi_loader/efi_helper.c')
-rw-r--r-- | lib/efi_loader/efi_helper.c | 286 |
1 files changed, 286 insertions, 0 deletions
diff --git a/lib/efi_loader/efi_helper.c b/lib/efi_loader/efi_helper.c index 17f27ca1a0..11066eb505 100644 --- a/lib/efi_loader/efi_helper.c +++ b/lib/efi_loader/efi_helper.c @@ -4,13 +4,20 @@ */ #define LOG_CATEGORY LOGC_EFI +#include <bootm.h> #include <env.h> +#include <image.h> +#include <log.h> #include <malloc.h> +#include <mapmem.h> #include <dm.h> #include <fs.h> +#include <efi_api.h> #include <efi_load_initrd.h> #include <efi_loader.h> #include <efi_variable.h> +#include <linux/libfdt.h> +#include <linux/list.h> #if defined(CONFIG_CMD_EFIDEBUG) || defined(CONFIG_EFI_LOAD_FILE2_INITRD) /* GUID used by Linux to identify the LoadFile2 protocol with the initrd */ @@ -281,3 +288,282 @@ bool efi_search_bootorder(u16 *bootorder, efi_uintn_t num, u32 target, u32 *inde return false; } + +/** + * efi_env_set_load_options() - set load options from environment variable + * + * @handle: the image handle + * @env_var: name of the environment variable + * @load_options: pointer to load options (output) + * Return: status code + */ +efi_status_t efi_env_set_load_options(efi_handle_t handle, + const char *env_var, + u16 **load_options) +{ + const char *env = env_get(env_var); + size_t size; + u16 *pos; + efi_status_t ret; + + *load_options = NULL; + if (!env) + return EFI_SUCCESS; + size = sizeof(u16) * (utf8_utf16_strlen(env) + 1); + pos = calloc(size, 1); + if (!pos) + return EFI_OUT_OF_RESOURCES; + *load_options = pos; + utf8_utf16_strcpy(&pos, env); + ret = efi_set_load_options(handle, size, *load_options); + if (ret != EFI_SUCCESS) { + free(*load_options); + *load_options = NULL; + } + return ret; +} + +/** + * copy_fdt() - Copy the device tree to a new location available to EFI + * + * The FDT is copied to a suitable location within the EFI memory map. + * Additional 12 KiB are added to the space in case the device tree needs to be + * expanded later with fdt_open_into(). + * + * @fdtp: On entry a pointer to the flattened device tree. + * On exit a pointer to the copy of the flattened device tree. + * FDT start + * Return: status code + */ +static efi_status_t copy_fdt(void **fdtp) +{ + unsigned long fdt_ram_start = -1L, fdt_pages; + efi_status_t ret = 0; + void *fdt, *new_fdt; + u64 new_fdt_addr; + uint fdt_size; + int i; + + for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) { + u64 ram_start = gd->bd->bi_dram[i].start; + u64 ram_size = gd->bd->bi_dram[i].size; + + if (!ram_size) + continue; + + if (ram_start < fdt_ram_start) + fdt_ram_start = ram_start; + } + + /* + * Give us at least 12 KiB of breathing room in case the device tree + * needs to be expanded later. + */ + fdt = *fdtp; + fdt_pages = efi_size_in_pages(fdt_totalsize(fdt) + 0x3000); + fdt_size = fdt_pages << EFI_PAGE_SHIFT; + + ret = efi_allocate_pages(EFI_ALLOCATE_ANY_PAGES, + EFI_ACPI_RECLAIM_MEMORY, fdt_pages, + &new_fdt_addr); + if (ret != EFI_SUCCESS) { + log_err("ERROR: Failed to reserve space for FDT\n"); + goto done; + } + new_fdt = (void *)(uintptr_t)new_fdt_addr; + memcpy(new_fdt, fdt, fdt_totalsize(fdt)); + fdt_set_totalsize(new_fdt, fdt_size); + + *fdtp = (void *)(uintptr_t)new_fdt_addr; +done: + return ret; +} + +/** + * get_config_table() - get configuration table + * + * @guid: GUID of the configuration table + * Return: pointer to configuration table or NULL + */ +static void *get_config_table(const efi_guid_t *guid) +{ + size_t i; + + for (i = 0; i < systab.nr_tables; i++) { + if (!guidcmp(guid, &systab.tables[i].guid)) + return systab.tables[i].table; + } + return NULL; +} + +/** + * efi_install_fdt() - install device tree + * + * If fdt is not EFI_FDT_USE_INTERNAL, the device tree located at that memory + * address will be installed as configuration table, otherwise the device + * tree located at the address indicated by environment variable fdt_addr or as + * fallback fdtcontroladdr will be used. + * + * On architectures using ACPI tables device trees shall not be installed as + * configuration table. + * + * @fdt: address of device tree or EFI_FDT_USE_INTERNAL to use + * the hardware device tree as indicated by environment variable + * fdt_addr or as fallback the internal device tree as indicated by + * the environment variable fdtcontroladdr + * Return: status code + */ +efi_status_t efi_install_fdt(void *fdt) +{ + struct bootm_headers img = { 0 }; + efi_status_t ret; + + /* + * The EBBR spec requires that we have either an FDT or an ACPI table + * but not both. + */ + if (CONFIG_IS_ENABLED(GENERATE_ACPI_TABLE) && fdt) + log_warning("WARNING: Can't have ACPI table and device tree - ignoring DT.\n"); + + if (fdt == EFI_FDT_USE_INTERNAL) { + const char *fdt_opt; + uintptr_t fdt_addr; + + /* Look for device tree that is already installed */ + if (get_config_table(&efi_guid_fdt)) + return EFI_SUCCESS; + /* Check if there is a hardware device tree */ + fdt_opt = env_get("fdt_addr"); + /* Use our own device tree as fallback */ + if (!fdt_opt) { + fdt_opt = env_get("fdtcontroladdr"); + if (!fdt_opt) { + log_err("ERROR: need device tree\n"); + return EFI_NOT_FOUND; + } + } + fdt_addr = hextoul(fdt_opt, NULL); + if (!fdt_addr) { + log_err("ERROR: invalid $fdt_addr or $fdtcontroladdr\n"); + return EFI_LOAD_ERROR; + } + fdt = map_sysmem(fdt_addr, 0); + } + + /* Install device tree */ + if (fdt_check_header(fdt)) { + log_err("ERROR: invalid device tree\n"); + return EFI_LOAD_ERROR; + } + + /* Create memory reservations as indicated by the device tree */ + efi_carve_out_dt_rsv(fdt); + + if (CONFIG_IS_ENABLED(GENERATE_ACPI_TABLE)) + return EFI_SUCCESS; + + /* Prepare device tree for payload */ + ret = copy_fdt(&fdt); + if (ret) { + log_err("ERROR: out of memory\n"); + return EFI_OUT_OF_RESOURCES; + } + + if (image_setup_libfdt(&img, fdt, NULL)) { + log_err("ERROR: failed to process device tree\n"); + return EFI_LOAD_ERROR; + } + + efi_try_purge_kaslr_seed(fdt); + + if (CONFIG_IS_ENABLED(EFI_TCG2_PROTOCOL_MEASURE_DTB)) { + ret = efi_tcg2_measure_dtb(fdt); + if (ret == EFI_SECURITY_VIOLATION) { + log_err("ERROR: failed to measure DTB\n"); + return ret; + } + } + + /* Install device tree as UEFI table */ + ret = efi_install_configuration_table(&efi_guid_fdt, fdt); + if (ret != EFI_SUCCESS) { + log_err("ERROR: failed to install device tree\n"); + return ret; + } + + return EFI_SUCCESS; +} + +/** + * do_bootefi_exec() - execute EFI binary + * + * The image indicated by @handle is started. When it returns the allocated + * memory for the @load_options is freed. + * + * @handle: handle of loaded image + * @load_options: load options + * Return: status code + * + * Load the EFI binary into a newly assigned memory unwinding the relocation + * information, install the loaded image protocol, and call the binary. + */ +efi_status_t do_bootefi_exec(efi_handle_t handle, void *load_options) +{ + efi_status_t ret; + efi_uintn_t exit_data_size = 0; + u16 *exit_data = NULL; + struct efi_event *evt; + + /* On ARM switch from EL3 or secure mode to EL2 or non-secure mode */ + switch_to_non_secure_mode(); + + /* + * The UEFI standard requires that the watchdog timer is set to five + * minutes when invoking an EFI boot option. + * + * Unified Extensible Firmware Interface (UEFI), version 2.7 Errata A + * 7.5. Miscellaneous Boot Services - EFI_BOOT_SERVICES.SetWatchdogTimer + */ + ret = efi_set_watchdog(300); + if (ret != EFI_SUCCESS) { + log_err("ERROR: Failed to set watchdog timer\n"); + goto out; + } + + /* Call our payload! */ + ret = EFI_CALL(efi_start_image(handle, &exit_data_size, &exit_data)); + if (ret != EFI_SUCCESS) { + log_err("## Application failed, r = %lu\n", + ret & ~EFI_ERROR_MASK); + if (exit_data) { + log_err("## %ls\n", exit_data); + efi_free_pool(exit_data); + } + } + + efi_restore_gd(); + +out: + free(load_options); + + if (IS_ENABLED(CONFIG_EFI_LOAD_FILE2_INITRD)) { + if (efi_initrd_deregister() != EFI_SUCCESS) + log_err("Failed to remove loadfile2 for initrd\n"); + } + + /* Notify EFI_EVENT_GROUP_RETURN_TO_EFIBOOTMGR event group. */ + list_for_each_entry(evt, &efi_events, link) { + if (evt->group && + !guidcmp(evt->group, + &efi_guid_event_group_return_to_efibootmgr)) { + efi_signal_event(evt); + EFI_CALL(systab.boottime->close_event(evt)); + break; + } + } + + /* Control is returned to U-Boot, disable EFI watchdog */ + efi_set_watchdog(0); + + return ret; +} |