aboutsummaryrefslogtreecommitdiff
path: root/lib/efi_loader/efi_helper.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/efi_loader/efi_helper.c')
-rw-r--r--lib/efi_loader/efi_helper.c286
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;
+}