sh: Allow for kernel command line concatenation.

So far kernel command line arguments could be passed in by a bootloader
or defined as CONFIG_CMDLINE, which completely overwriting the first one.

This change allows a developer to declare selected kernel parameters in
a kernel configuration (eg. project-specific defconfig), retaining
possibility of passing others by a bootloader.

The obvious examples of the first type are MTD partition or
bigphysarea-like region definitions, while "debug" option or network
configuration should be given by a bootloader or a JTAG boot script.

Signed-off-by: Pawel Moll <pawel.moll@st.com>
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 23 insertions, 4 deletions

diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 80b4f9a743a1..2f5352c06a0e 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -767,12 +767,31 @@ config UBC_WAKEUP
 
 	  If unsure, say N.
 
-config CMDLINE_BOOL
-	bool "Default bootloader kernel arguments"
+choice
+	prompt "Kernel command line"
+	optional
+	default CMDLINE_OVERWRITE
+	help
+	  Setting this option allows the kernel command line arguments
+	  to be set.
+
+config CMDLINE_OVERWRITE
+	bool "Overwrite bootloader kernel arguments"
+	help
+	  Given string will overwrite any arguments passed in by
+	  a bootloader.
+
+config CMDLINE_EXTEND
+	bool "Extend bootloader kernel arguments"
+	help
+	  Given string will be concatenated with arguments passed in
+	  by a bootloader.
+
+endchoice
 
 config CMDLINE
-	string "Initial kernel command string"
-	depends on CMDLINE_BOOL
+	string "Kernel command line arguments string"
+	depends on CMDLINE_OVERWRITE || CMDLINE_EXTEND
 	default "console=ttySC1,115200"
 
 endmenu