From 8cd6686ef81effb3c30f0508368db3d0600f289d Mon Sep 17 00:00:00 2001 From: Chris Blake Date: Sat, 30 Sep 2017 11:14:20 -0500 Subject: [PATCH] mpc85xx: Add cmdline override patch This patch adds a new kernel option called CONFIG_CMDLINE_OVERRIDE. This setting is for devices with locked down u-boot environments, where users are unable to change the default bootargs. When set, the fdt driver will propagate the cmdline for the kernel from chosen/bootargs-override instead of chosen/bootargs as long as it exists within the DTB. Signed-off-by: Chris Blake --- target/linux/mpc85xx/config-4.9 | 1 + .../102-powerpc-add-cmdline-override.patch | 37 +++++++++++++++++++ 2 files changed, 38 insertions(+) create mode 100644 target/linux/mpc85xx/patches-4.9/102-powerpc-add-cmdline-override.patch diff --git a/target/linux/mpc85xx/config-4.9 b/target/linux/mpc85xx/config-4.9 index 64ab239613..9086ba9177 100644 --- a/target/linux/mpc85xx/config-4.9 +++ b/target/linux/mpc85xx/config-4.9 @@ -37,6 +37,7 @@ CONFIG_CLONE_BACKWARDS=y CONFIG_CLZ_TAB=y CONFIG_CMDLINE="console=ttyS0,115200" CONFIG_CMDLINE_BOOL=y +CONFIG_CMDLINE_OVERRIDE=y # CONFIG_CORENET_GENERIC is not set # CONFIG_CPM2 is not set CONFIG_CPU_BIG_ENDIAN=y diff --git a/target/linux/mpc85xx/patches-4.9/102-powerpc-add-cmdline-override.patch b/target/linux/mpc85xx/patches-4.9/102-powerpc-add-cmdline-override.patch new file mode 100644 index 0000000000..3d59927d1d --- /dev/null +++ b/target/linux/mpc85xx/patches-4.9/102-powerpc-add-cmdline-override.patch @@ -0,0 +1,37 @@ +--- a/arch/powerpc/Kconfig ++++ b/arch/powerpc/Kconfig +@@ -707,6 +707,14 @@ config CMDLINE_FORCE + This is useful if you cannot or don't want to change the + command-line options your boot loader passes to the kernel. + ++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 EXTRA_TARGETS + string "Additional default image types" + help +--- a/drivers/of/fdt.c ++++ b/drivers/of/fdt.c +@@ -1079,6 +1079,17 @@ int __init early_init_dt_scan_chosen(uns + if (p != NULL && l > 0) + strlcpy(data, p, min((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 -- 2.30.2