openwrt/target/linux/ipq806x/patches-5.10/900-arm-add-cmdline-override.patch
Rafał Miłecki 11759a5bf3 kernel: backport of changes & helpers
This code is required for upcoming NVMEM changes.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
2023-01-07 17:45:17 +01:00

38 lines
1.3 KiB
Diff

--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1790,6 +1790,14 @@ config ARM_ATAG_DTB_COMPAT_CMDLINE_MANGL
endchoice
+config CMDLINE_OVERRIDE
+ bool "Use alternative cmdline from device tree"
+ help
+ Some bootloaders may have uneditable bootargs. While CMDLINE_FORCE can
+ be used, this is not a good option for kernels that are shared across
+ devices. This setting enables using "chosen/cmdline-override" as the
+ cmdline if it exists in the device tree.
+
config CMDLINE
string "Default kernel command string"
default ""
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -1058,6 +1058,17 @@ int __init early_init_dt_scan_chosen(uns
if (p != NULL && l > 0)
strlcat(data, p, min_t(int, strlen(data) + (int)l, COMMAND_LINE_SIZE));
+ /* CONFIG_CMDLINE_OVERRIDE is used to fallback to a different
+ * device tree option of chosen/bootargs-override. This is
+ * helpful on boards where u-boot sets bootargs, and is unable
+ * to be modified.
+ */
+#ifdef CONFIG_CMDLINE_OVERRIDE
+ p = of_get_flat_dt_prop(node, "bootargs-override", &l);
+ if (p != NULL && l > 0)
+ strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE));
+#endif
+
/*
* CONFIG_CMDLINE is meant to be a default in case nothing else
* managed to set the command line, unless CONFIG_CMDLINE_FORCE