We have previously added logic to allow a "fallback" option to be specified in the extlinux configuration. Provide a command that allows us to set this as the preferred default option when booting.
Combined with the bootcount functionality, this allows the "altbootcmd" to provide a means of falling back to a previously known good state after a failed update. For example, if "bootcmd" is set to:
bootflow scan -lb
We would set "altbootcmd" to:
bootmeth set extlinux fallback 1; bootflow scan -lb
Causing the boot process to boot from the fallback option.
Reviewed-by: Simon Glass sjg@chromium.org Signed-off-by: Martyn Welch martyn.welch@collabora.com ---
Changes since v1: - Addition of documentation of bootmeth sub command and bootstd feature.
boot/bootmeth-uclass.c | 25 +++++++++++ boot/bootmeth_extlinux.c | 73 +++++++++++++++++++++++++++++++- cmd/bootmeth.c | 25 ++++++++++- doc/develop/bootstd/overview.rst | 10 ++++- doc/usage/cmd/bootmeth.rst | 38 ++++++++++++++++- include/bootmeth.h | 31 ++++++++++++++ 6 files changed, 196 insertions(+), 6 deletions(-)
diff --git a/boot/bootmeth-uclass.c b/boot/bootmeth-uclass.c index c0abadef97..5b5fea39b3 100644 --- a/boot/bootmeth-uclass.c +++ b/boot/bootmeth-uclass.c @@ -251,6 +251,31 @@ int bootmeth_set_order(const char *order_str) return 0; }
+int bootmeth_set_property(const char *name, const char *property, const char *value) +{ + int ret; + int len; + struct udevice *dev; + const struct bootmeth_ops *ops; + + len = strlen(name); + + ret = uclass_find_device_by_namelen(UCLASS_BOOTMETH, name, len, + &dev); + if (ret) { + printf("Unknown bootmeth '%s'\n", name); + return ret; + } + + ops = bootmeth_get_ops(dev); + if (!ops->set_property) { + printf("set_property not found\n"); + return -ENODEV; + } + + return ops->set_property(dev, property, value); +} + int bootmeth_setup_fs(struct bootflow *bflow, struct blk_desc *desc) { int ret; diff --git a/boot/bootmeth_extlinux.c b/boot/bootmeth_extlinux.c index 26c61a65e2..be8fbf4df6 100644 --- a/boot/bootmeth_extlinux.c +++ b/boot/bootmeth_extlinux.c @@ -21,6 +21,39 @@ #include <mmc.h> #include <pxe_utils.h>
+struct extlinux_plat { + bool use_fallback; +}; + +enum extlinux_option_type { + EO_FALLBACK, + EO_INVALID +}; + +struct extlinux_option { + char *name; + enum extlinux_option_type option; +}; + +static const struct extlinux_option options[] = { + {"fallback", EO_FALLBACK}, + {NULL, EO_INVALID} +}; + +static enum extlinux_option_type get_option(const char *option) +{ + int i = 0; + + while (options[i].name) { + if (!strcmp(options[i].name, option)) + return options[i].option; + + i++; + } + + return EO_INVALID; +}; + static int extlinux_get_state_desc(struct udevice *dev, char *buf, int maxsize) { if (IS_ENABLED(CONFIG_SANDBOX)) { @@ -142,14 +175,18 @@ static int extlinux_boot(struct udevice *dev, struct bootflow *bflow) struct cmd_tbl cmdtp = {}; /* dummy */ struct pxe_context ctx; struct extlinux_info info; + struct extlinux_plat *plat; ulong addr; int ret;
addr = map_to_sysmem(bflow->buf); info.dev = dev; info.bflow = bflow; + + plat = dev_get_plat(dev); + ret = pxe_setup_ctx(&ctx, &cmdtp, extlinux_getfile, &info, true, - bflow->fname, false, false); + bflow->fname, false, plat->use_fallback); if (ret) return log_msg_ret("ctx", -EINVAL);
@@ -160,6 +197,38 @@ static int extlinux_boot(struct udevice *dev, struct bootflow *bflow) return 0; }
+static int extlinux_set_property(struct udevice *dev, const char *property, const char *value) +{ + struct extlinux_plat *plat; + static enum extlinux_option_type option; + + plat = dev_get_plat(dev); + + option = get_option(property); + if (option == EO_INVALID) { + printf("Invalid option\n"); + return -EINVAL; + } + + switch (option) { + case EO_FALLBACK: + if (!strcmp(value, "1")) { + plat->use_fallback = true; + } else if (!strcmp(value, "0")) { + plat->use_fallback = false; + } else { + printf("Unexpected value '%s'\n", value); + return -EINVAL; + } + break; + default: + printf("Unrecognised property '%s'\n", property); + return -EINVAL; + } + + return 0; +} + static int extlinux_bootmeth_bind(struct udevice *dev) { struct bootmeth_uc_plat *plat = dev_get_uclass_plat(dev); @@ -176,6 +245,7 @@ static struct bootmeth_ops extlinux_bootmeth_ops = { .read_bootflow = extlinux_read_bootflow, .read_file = bootmeth_common_read_file, .boot = extlinux_boot, + .set_property = extlinux_set_property, };
static const struct udevice_id extlinux_bootmeth_ids[] = { @@ -190,4 +260,5 @@ U_BOOT_DRIVER(bootmeth_1extlinux) = { .of_match = extlinux_bootmeth_ids, .ops = &extlinux_bootmeth_ops, .bind = extlinux_bootmeth_bind, + .plat_auto = sizeof(struct extlinux_plat) }; diff --git a/cmd/bootmeth.c b/cmd/bootmeth.c index ebf8b7e253..2f41fa1bec 100644 --- a/cmd/bootmeth.c +++ b/cmd/bootmeth.c @@ -103,10 +103,31 @@ static int do_bootmeth_order(struct cmd_tbl *cmdtp, int flag, int argc, return 0; }
+static int do_bootmeth_set(struct cmd_tbl *cmdtp, int flag, int argc, + char *const argv[]) +{ + int ret; + + if (argc < 4) { + printf("Required parameters not provided\n"); + return CMD_RET_FAILURE; + } + + ret = bootmeth_set_property(argv[1], argv[2], argv[3]); + if (ret) { + printf("Failed (err=%d)\n", ret); + return CMD_RET_FAILURE; + } + + return 0; +} + U_BOOT_LONGHELP(bootmeth, "list [-a] - list available bootmeths (-a all)\n" - "bootmeth order [<bd> ...] - select bootmeth order / subset to use"); + "bootmeth order [<bd> ...] - select bootmeth order / subset to use\n" + "bootmeth set <bootmeth> <property> <value> - set optional property");
U_BOOT_CMD_WITH_SUBCMDS(bootmeth, "Boot methods", bootmeth_help_text, U_BOOT_SUBCMD_MKENT(list, 2, 1, do_bootmeth_list), - U_BOOT_SUBCMD_MKENT(order, CONFIG_SYS_MAXARGS, 1, do_bootmeth_order)); + U_BOOT_SUBCMD_MKENT(order, CONFIG_SYS_MAXARGS, 1, do_bootmeth_order), + U_BOOT_SUBCMD_MKENT(set, CONFIG_SYS_MAXARGS, 1, do_bootmeth_set)); diff --git a/doc/develop/bootstd/overview.rst b/doc/develop/bootstd/overview.rst index c6f003851b..a2913cd47b 100644 --- a/doc/develop/bootstd/overview.rst +++ b/doc/develop/bootstd/overview.rst @@ -103,6 +103,12 @@ provide a `read_bootflow()` method which checks whatever bootdevs it likes, then returns the bootflow, if found. Some of these bootmeths may be very slow, if they scan a lot of devices.
+The extlinux bootmeth also allows for bootmeth specific configuration to be +set. A bootmeth that wishes to support this provides the `set_property()` +method. This allows string properties and values to be passed to the bootmeth. +It is up to the bootmeth to determine what action to take when this method is +called. +
Boot process ------------ @@ -459,8 +465,8 @@ Three commands are available: See :doc:`/usage/cmd/bootflow`
`bootmeth` - Allow listing of available bootmethds and setting the order in which they - are tried. See :doc:`/usage/cmd/bootmeth` + Allow listing of available bootmethds, setting the order in which they are + tried and bootmeth specific configuration. See :doc:`/usage/cmd/bootmeth`
.. _BootflowStates:
diff --git a/doc/usage/cmd/bootmeth.rst b/doc/usage/cmd/bootmeth.rst index c3d2ec1574..4f899d92b2 100644 --- a/doc/usage/cmd/bootmeth.rst +++ b/doc/usage/cmd/bootmeth.rst @@ -12,7 +12,8 @@ Synopsis ::
bootmeth list [-a] - list selected bootmeths (-a for all) - bootmeth order "[<bm> ...]" - select the order of bootmeths\n" + bootmeth order "[<bm> ...]" - select the order of bootmeths + bootmeth set <bootmeth> <property> <value> - set optional property
Description @@ -112,3 +113,38 @@ which are not:: - 4 efi_mgr EFI bootmgr flow ----- --- ------------------ ------------------ (5 bootmeths) + + +bootmeth set +~~~~~~~~~~~~ + +Allows setting of bootmeth specific configuration. This allows finer grain +control over the boot process in specific instances. + + +Supported Configuration Options +------------------------------- + +The following configuration options are currently supported: + +======== =================== ====== =============================== +Property Supported Bootmeths Values Description +======== =================== ====== =============================== +fallback extlinux 0 | 1 Enable or disable fallback path +======== =================== ====== =============================== + + +Bootmeth set Example +-------------------- + +With the bootcount functionality enabled, when the bootlimit is reached, the +`altbootcmd` environment variable lists the command used for booting rather +than `bootcmd`. We can set the fallback configuration to cause the fallback +boot option to be preferred, to revert to a previous known working boot option +after a failed update for example. So if `bootcmd` is set to:: + + bootflow scan -lb + +We would set "altbootcmd" to:: + + bootmeth set extlinux fallback 1; bootflow scan -lb diff --git a/include/bootmeth.h b/include/bootmeth.h index 4d8ca48efd..a08ebf005a 100644 --- a/include/bootmeth.h +++ b/include/bootmeth.h @@ -146,6 +146,22 @@ struct bootmeth_ops { * something changes, other -ve on other error */ int (*boot)(struct udevice *dev, struct bootflow *bflow); + + /** + * set_property() - set the bootmeth property + * + * This allows the setting of boot method specific properties to enable + * automated finer grain control of the boot process + * + * @name: String containing the name of the relevant boot method + * @property: String containing the name of the property to set + * @value: String containing the value to be set for the specified + * property + * Return: 0 if OK, -ENODEV if an unknown bootmeth or property is + * provided, -ENOENT if there are no bootmeth devices + */ + int (*set_property)(struct udevice *dev, const char *property, + const char *value); };
#define bootmeth_get_ops(dev) ((struct bootmeth_ops *)(dev)->driver->ops) @@ -290,6 +306,21 @@ int bootmeth_setup_iter_order(struct bootflow_iter *iter, bool include_global); */ int bootmeth_set_order(const char *order_str);
+/** + * bootmeth_set_property() - Set the bootmeth property + * + * This allows the setting of boot method specific properties to enable + * automated finer grain control of the boot process + * + * @name: String containing the name of the relevant boot method + * @property: String containing the name of the property to set + * @value: String containing the value to be set for the specified property + * Return: 0 if OK, -ENODEV if an unknown bootmeth or property is provided, + * -ENOENT if there are no bootmeth devices + */ +int bootmeth_set_property(const char *name, const char *property, + const char *value); + /** * bootmeth_setup_fs() - Set up read to read a file *