[PATCH v2 1/2] bootstd: Add implementation for bootmeth rauc
Martin Schwan
m.schwan at phytec.de
Mon Jun 2 13:31:34 CEST 2025
Add a bootmeth driver which supports booting A/B system with RAUC as
their update client.
Signed-off-by: Martin Schwan <m.schwan at phytec.de>
---
boot/Kconfig | 51 ++++++
boot/Makefile | 1 +
boot/bootmeth_rauc.c | 432 +++++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 484 insertions(+)
diff --git a/boot/Kconfig b/boot/Kconfig
index 30eb5b328d7ad8a73a2e84812dd7853b66039164..a610cf9faf99cd5480f94dcac89c3401cca394ae 100644
--- a/boot/Kconfig
+++ b/boot/Kconfig
@@ -855,6 +855,57 @@ config EXPO
The expo can be presented in graphics form using a vidconsole, or in
text form on a serial console.
+config BOOTMETH_RAUC
+ bool "Bootdev support for RAUC A/B systems"
+ default y if BOOTSTD_FULL
+ depends on CMDLINE
+ select BOOTMETH_GLOBAL
+ select HUSH_PARSER
+ help
+ Enables support for booting RAUC A/B systems from MMC devices. This
+ makes the bootdevs look for a 'boot.scr.uimg' or 'boot.scr' in the
+ respective boot partitions, describing how to boot the distro.
+
+if BOOTMETH_RAUC
+
+config BOOTMETH_RAUC_BOOT_ORDER
+ string "RAUC boot order"
+ default "A B"
+ help
+ Sets the default boot order. This must be list of space-separated
+ strings naming the individual boot slots. Each entry in this string
+ should correspond to an existing slot on the target's flash device.
+
+config BOOTMETH_RAUC_PARTITIONS
+ string "RAUC boot and root partitions indexes"
+ default "1,2 3,4"
+ help
+ Sets the partition indexes of boot and root slots. This must be a list
+ of comma-separated pair values, which in turn are separated by spaces.
+ The first value in pair is for the boot partition and second for the
+ root partition.
+
+config BOOTMETH_RAUC_DEFAULT_TRIES
+ int "RAUC slot default tries"
+ default 3
+ help
+ Sets how many times a slot should be tried booting, before considering
+ it to be bad.
+
+config BOOTMETH_RAUC_RESET_ALL_ZERO_TRIES
+ bool "Reset slot tries when all RAUC slots have zero tries left"
+ default y
+ help
+ When all slots have zero tries left or no valid slot was found, reset
+ to the default boot order set by BOOTMETH_RAUC_BOOT_ORDER and set the
+ slot tries to their default value specified by
+ BOOTMETH_RAUC_DEFAULT_TRIES.
+
+ This prevents a system from remaining in an unbootable state, after
+ all slot tries were decremented to zero.
+
+endif # BOOTMETH_RAUC
+
config BOOTMETH_SANDBOX
def_bool y
depends on SANDBOX
diff --git a/boot/Makefile b/boot/Makefile
index 71dafaefa76bca7896741dd896829575bd9e8f10..46f27e71856c598a866424cb93ee01444ea6a19a 100644
--- a/boot/Makefile
+++ b/boot/Makefile
@@ -32,6 +32,7 @@ obj-$(CONFIG_$(PHASE_)BOOTMETH_EXTLINUX_PXE) += bootmeth_pxe.o
obj-$(CONFIG_$(PHASE_)BOOTMETH_EFILOADER) += bootmeth_efi.o
obj-$(CONFIG_$(PHASE_)BOOTMETH_CROS) += bootm.o bootm_os.o bootmeth_cros.o
obj-$(CONFIG_$(PHASE_)BOOTMETH_QFW) += bootmeth_qfw.o
+obj-$(CONFIG_$(PHASE_)BOOTMETH_RAUC) += bootmeth_rauc.o
obj-$(CONFIG_$(PHASE_)BOOTMETH_SANDBOX) += bootmeth_sandbox.o
obj-$(CONFIG_$(PHASE_)BOOTMETH_SCRIPT) += bootmeth_script.o
obj-$(CONFIG_$(PHASE_)CEDIT) += cedit.o
diff --git a/boot/bootmeth_rauc.c b/boot/bootmeth_rauc.c
new file mode 100644
index 0000000000000000000000000000000000000000..4d48d643c0a727d5ebd5f3514c173f0dd824b7cd
--- /dev/null
+++ b/boot/bootmeth_rauc.c
@@ -0,0 +1,432 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Bootmethod for distro boot with RAUC
+ *
+ * Copyright 2025 PHYTEC Messtechnik GmbH
+ * Written by Martin Schwan <m.schwan at phytec.de>
+ */
+
+#define LOG_CATEGORY UCLASS_BOOTSTD
+
+#include <blk.h>
+#include <bootflow.h>
+#include <bootmeth.h>
+#include <bootstd.h>
+#include <dm.h>
+#include <env.h>
+#include <fs.h>
+#include <malloc.h>
+#include <mapmem.h>
+#include <string.h>
+#include <asm/cache.h>
+
+/* Length of env var "BOOT_*_LEFT" */
+#define BOOT_LEFT_LEN (5 + 32 + 5)
+
+static const char * const script_names[] = { "boot.scr", "boot.scr.uimg", NULL };
+
+/**
+ * struct distro_rauc_slot - Slot information
+ *
+ * A slot describes the unit of a bootable system consisting of one or multiple
+ * partitions. This usually includes a root filesystem, kernel and potentially other
+ * files, like device trees and boot scripts for that particular distribution.
+ *
+ * @name The slot name
+ * @boot_part The boot partition number on disk
+ * @root_part The root partition number on disk
+ */
+struct distro_rauc_slot {
+ char *name;
+ int boot_part;
+ int root_part;
+};
+
+/**
+ * struct distro_rauc_priv - Private data
+ *
+ * @slots All slots of the device in default order
+ * @boot_order String of the current boot order containing the active slot names
+ */
+struct distro_rauc_priv {
+ struct distro_rauc_slot **slots;
+};
+
+static struct distro_rauc_slot *get_slot(struct distro_rauc_priv *priv,
+ const char *slot_name)
+{
+ int i;
+
+ for (i = 0; priv->slots[i]->name; i++) {
+ if (!strcmp(priv->slots[i]->name, slot_name))
+ return priv->slots[i];
+ }
+
+ return NULL;
+}
+
+static int distro_rauc_check(struct udevice *dev, struct bootflow_iter *iter)
+{
+ /*
+ * This distro only works on whole MMC devices, as multiple partitions
+ * are needed for an A/B system.
+ */
+ if (bootflow_iter_check_mmc(iter))
+ return log_msg_ret("mmc", -EOPNOTSUPP);
+ if (iter->part)
+ return log_msg_ret("part", -EOPNOTSUPP);
+
+ return 0;
+}
+
+static int distro_rauc_scan_boot_part(struct bootflow *bflow)
+{
+ struct blk_desc *desc;
+ struct distro_rauc_priv *priv;
+ char *boot_order;
+ const char **boot_order_list;
+ bool exists;
+ int ret;
+ int i;
+ int j;
+
+ desc = dev_get_uclass_plat(bflow->blk);
+
+ priv = bflow->bootmeth_priv;
+ if (!priv || !priv->slots)
+ return log_msg_ret("priv", -EINVAL);
+
+ boot_order = env_get("BOOT_ORDER");
+ boot_order_list = str_to_list(boot_order);
+ for (i = 0; boot_order_list[i]; i++) {
+ exists = false;
+ for (j = 0; script_names[j]; j++) {
+ const struct distro_rauc_slot *slot;
+
+ slot = get_slot(priv, boot_order_list[i]);
+ if (!slot)
+ return log_msg_ret("env", -ENOENT);
+ ret = fs_set_blk_dev_with_part(desc, slot->boot_part);
+ if (ret)
+ return log_msg_ret("blk", ret);
+ exists |= fs_exists(script_names[j]);
+ }
+ if (!exists)
+ return log_msg_ret("fs", -ENOENT);
+ }
+ str_free_list(boot_order_list);
+
+ return 0;
+}
+
+static int distro_rauc_read_bootflow(struct udevice *dev, struct bootflow *bflow)
+{
+ struct distro_rauc_priv *priv;
+ int ret;
+ char *slot;
+ int i;
+ char *partitions;
+ char *boot_order;
+ const char *default_boot_order;
+ const char **default_boot_order_list;
+ char *boot_order_copy;
+ char boot_left[BOOT_LEFT_LEN];
+ char *parts;
+
+ /* Get RAUC variables or set their default values */
+ boot_order = env_get("BOOT_ORDER");
+ if (!boot_order) {
+ log_debug("BOOT_ORDER did not exist yet, setting default value\n");
+ if (env_set("BOOT_ORDER", CONFIG_BOOTMETH_RAUC_BOOT_ORDER))
+ return log_msg_ret("env", -EPERM);
+ boot_order = CONFIG_BOOTMETH_RAUC_BOOT_ORDER;
+ }
+ default_boot_order = CONFIG_BOOTMETH_RAUC_BOOT_ORDER;
+ default_boot_order_list = str_to_list(default_boot_order);
+ for (i = 0; default_boot_order_list[i]; i++) {
+ sprintf(boot_left, "BOOT_%s_LEFT", default_boot_order_list[i]);
+ if (!env_get(boot_left)) {
+ log_debug("%s did not exist yet, setting default value\n",
+ boot_left);
+ if (!env_set_ulong(boot_left, CONFIG_BOOTMETH_RAUC_DEFAULT_TRIES))
+ return log_msg_ret("env", -EPERM);
+ }
+ }
+ str_free_list(default_boot_order_list);
+
+ priv = calloc(1, sizeof(struct distro_rauc_priv));
+ if (!priv)
+ return log_msg_ret("buf", -ENOMEM);
+ priv->slots = calloc(1, sizeof(struct distro_rauc_slot));
+
+ /* Copy default boot_order, so we can leave the original unmodified */
+ boot_order_copy = strdup(default_boot_order);
+ partitions = strdup(CONFIG_BOOTMETH_RAUC_PARTITIONS);
+
+ for (i = 1;
+ (parts = strsep(&partitions, " ")) &&
+ (slot = strsep(&boot_order_copy, " "));
+ i++) {
+ struct distro_rauc_slot *s;
+
+ s = calloc(1, sizeof(struct distro_rauc_slot));
+ s->name = strdup(slot);
+ s->boot_part = simple_strtoul(strsep(&parts, ","), NULL, 10);
+ s->root_part = simple_strtoul(strsep(&parts, ","), NULL, 10);
+ priv->slots = realloc(priv->slots, (i + 1) *
+ sizeof(struct distro_rauc_slot));
+ priv->slots[i - 1] = s;
+ priv->slots[i]->name = NULL;
+ }
+
+ bflow->bootmeth_priv = priv;
+
+ ret = distro_rauc_scan_boot_part(bflow);
+ if (ret < 0) {
+ for (i = 0; priv->slots[i]->name; i++) {
+ free(priv->slots[i]->name);
+ free(priv->slots[i]);
+ }
+ free(priv);
+ free(boot_order_copy);
+ bflow->bootmeth_priv = NULL;
+ return ret;
+ }
+
+ bflow->state = BOOTFLOWST_READY;
+
+ return 0;
+}
+
+static int distro_rauc_read_file(struct udevice *dev, struct bootflow *bflow,
+ const char *file_path, ulong addr,
+ enum bootflow_img_t type, ulong *sizep)
+{
+ /*
+ * Reading individual files is not supported since we only operate on
+ * whole MMC devices (because we require multiple partitions).
+ */
+ return log_msg_ret("Unsupported", -ENOSYS);
+}
+
+static int distro_rauc_load_boot_script(struct bootflow *bflow,
+ const struct distro_rauc_slot *slot)
+{
+ struct blk_desc *desc;
+ struct distro_rauc_priv *priv;
+ struct udevice *bootstd;
+ const char *const *prefixes;
+ int ret;
+ int i;
+ int j;
+
+ ret = uclass_first_device_err(UCLASS_BOOTSTD, &bootstd);
+ if (ret)
+ return log_msg_ret("std", ret);
+ prefixes = bootstd_get_prefixes(bootstd);
+
+ desc = dev_get_uclass_plat(bflow->blk);
+ priv = bflow->bootmeth_priv;
+ if (!priv || !priv->slots)
+ return log_msg_ret("priv", -EINVAL);
+
+ bflow->part = slot->boot_part;
+ if (!bflow->part)
+ return log_msg_ret("part", -ENOENT);
+
+ ret = bootmeth_setup_fs(bflow, desc);
+ if (ret)
+ return log_msg_ret("set", ret);
+
+ for (i = 0; prefixes[i] && bflow->state != BOOTFLOWST_FILE; i++) {
+ for (j = 0; script_names[j] && bflow->state != BOOTFLOWST_FILE; j++) {
+ if (!bootmeth_try_file(bflow, desc, prefixes[i], script_names[j])) {
+ log_debug("Found file '%s%s' in %s.part_%x\n",
+ prefixes[i], script_names[j],
+ bflow->dev->name, bflow->part);
+ bflow->subdir = strdup(prefixes[i]);
+ }
+ }
+ }
+ if (bflow->state != BOOTFLOWST_FILE)
+ return log_msg_ret("file", -ENOENT);
+
+ ret = bootmeth_alloc_file(bflow, 0x10000, ARCH_DMA_MINALIGN,
+ (enum bootflow_img_t)IH_TYPE_SCRIPT);
+ if (ret)
+ return log_msg_ret("read", ret);
+
+ return 0;
+}
+
+static int find_active_slot(char **slot_name, ulong *slot_tries)
+{
+ ulong tries;
+ char boot_left[BOOT_LEFT_LEN];
+ char *boot_order;
+ const char **boot_order_list;
+ bool slot_found = false;
+ int ret;
+ int i;
+
+ boot_order = env_get("BOOT_ORDER");
+ if (!boot_order)
+ return log_msg_ret("env", -ENOENT);
+ boot_order_list = str_to_list(boot_order);
+ for (i = 0; boot_order_list[i] && !slot_found; i++) {
+ sprintf(boot_left, "BOOT_%s_LEFT", boot_order_list[i]);
+ tries = env_get_ulong(boot_left, 10, ULONG_MAX);
+ if (tries == ULONG_MAX)
+ return log_msg_ret("env", -ENOENT);
+
+ if (tries) {
+ ret = env_set_ulong(boot_left, tries - 1);
+ if (ret)
+ return log_msg_ret("env", ret);
+ *slot_name = strdup(boot_order_list[i]);
+ *slot_tries = tries;
+ slot_found = true;
+ }
+ }
+ str_free_list(boot_order_list);
+
+ if (!slot_found) {
+ if (IS_ENABLED(CONFIG_BOOTMETH_RAUC_RESET_ALL_ZERO_TRIES)) {
+ log_warning("WARNING: No valid slot found\n");
+ log_info("INFO: Resetting boot order and all slot tries\n");
+ boot_order_list = str_to_list(CONFIG_BOOTMETH_RAUC_BOOT_ORDER);
+ for (i = 0; boot_order_list[i]; i++) {
+ sprintf(boot_left, "BOOT_%s_LEFT", boot_order_list[i]);
+ ret = env_set_ulong(boot_left, CONFIG_BOOTMETH_RAUC_DEFAULT_TRIES);
+ if (ret)
+ return log_msg_ret("env", ret);
+ }
+ str_free_list(boot_order_list);
+ ret = env_save();
+ if (ret)
+ return log_msg_ret("env", ret);
+ do_reset(NULL, 0, 0, NULL);
+ }
+ log_err("ERROR: No valid slot found\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int distro_rauc_boot(struct udevice *dev, struct bootflow *bflow)
+{
+ struct blk_desc *desc;
+ struct distro_rauc_priv *priv;
+ const struct distro_rauc_slot *slot;
+ char *boot_order;
+ const char **boot_order_list;
+ char *active_slot;
+ ulong active_slot_tries;
+ char raucargs[64];
+ char boot_left[BOOT_LEFT_LEN];
+ ulong addr;
+ int ret = 0;
+ int i;
+
+ desc = dev_get_uclass_plat(bflow->blk);
+ if (desc->uclass_id != UCLASS_MMC)
+ return log_msg_ret("blk", -EINVAL);
+ priv = bflow->bootmeth_priv;
+
+ /* Device info variables */
+ ret = env_set("devtype", blk_get_devtype(bflow->blk));
+ if (ret)
+ return log_msg_ret("env", ret);
+
+ ret = env_set_hex("devnum", desc->devnum);
+ if (ret)
+ return log_msg_ret("env", ret);
+
+ /* Find active, valid slot */
+ ret = find_active_slot(&active_slot, &active_slot_tries);
+ if (ret)
+ return log_msg_ret("env", ret);
+
+ /* Kernel command line arguments */
+ sprintf(raucargs, "rauc.slot=%s", active_slot);
+ ret = env_set("raucargs", raucargs);
+ if (ret)
+ return log_msg_ret("env", ret);
+
+ /* Active slot info */
+ slot = get_slot(priv, active_slot);
+ if (!slot)
+ return log_msg_ret("env", -ENOENT);
+ ret = env_set_hex("distro_bootpart", slot->boot_part);
+ if (ret)
+ return log_msg_ret("env", ret);
+ ret = env_set_hex("distro_rootpart", slot->root_part);
+ if (ret)
+ return log_msg_ret("env", ret);
+ ret = env_save();
+ if (ret)
+ return log_msg_ret("env", ret);
+
+ /* Load distro boot script */
+ ret = distro_rauc_load_boot_script(bflow, slot);
+ if (ret)
+ return log_msg_ret("load", ret);
+
+ log_info("INFO: Booting slot %s, %lu of %d tries left\n",
+ active_slot, active_slot_tries, CONFIG_BOOTMETH_RAUC_DEFAULT_TRIES);
+
+ log_debug("devtype: %s\n", env_get("devtype"));
+ log_debug("devnum: %s\n", env_get("devnum"));
+ log_debug("distro_bootpart: %s\n", env_get("distro_bootpart"));
+ log_debug("distro_rootpart: %s\n", env_get("distro_rootpart"));
+ log_debug("raucargs: %s\n", env_get("raucargs"));
+ boot_order = env_get("BOOT_ORDER");
+ if (!boot_order)
+ return log_msg_ret("env", -EPERM);
+ log_debug("BOOT_ORDER: %s\n", boot_order);
+ boot_order_list = str_to_list(boot_order);
+ for (i = 0; boot_order_list[i]; i++) {
+ sprintf(boot_left, "BOOT_%s_LEFT", boot_order_list[i]);
+ log_debug("%s: %s\n", boot_left, env_get(boot_left));
+ }
+ str_free_list(boot_order_list);
+
+ /* Run distro boot script */
+ addr = map_to_sysmem(bflow->buf);
+ ret = cmd_source_script(addr, NULL, NULL);
+ if (ret)
+ return log_msg_ret("boot", ret);
+
+ return 0;
+}
+
+static int distro_rauc_bootmeth_bind(struct udevice *dev)
+{
+ struct bootmeth_uc_plat *plat = dev_get_uclass_plat(dev);
+
+ plat->desc = "RAUC distro boot from MMC";
+ plat->flags = BOOTMETHF_GLOBAL;
+
+ return 0;
+}
+
+static struct bootmeth_ops distro_rauc_bootmeth_ops = {
+ .check = distro_rauc_check,
+ .read_bootflow = distro_rauc_read_bootflow,
+ .read_file = distro_rauc_read_file,
+ .boot = distro_rauc_boot,
+};
+
+static const struct udevice_id distro_rauc_bootmeth_ids[] = {
+ { .compatible = "u-boot,distro-rauc" },
+ { }
+};
+
+U_BOOT_DRIVER(bootmeth_rauc) = {
+ .name = "bootmeth_rauc",
+ .id = UCLASS_BOOTMETH,
+ .of_match = distro_rauc_bootmeth_ids,
+ .ops = &distro_rauc_bootmeth_ops,
+ .bind = distro_rauc_bootmeth_bind,
+};
--
2.49.0
More information about the U-Boot
mailing list