autoconfig.mk: Make it possible to define configs from other configs

bthebaudeau · albert-aribaud-u-boot · commit 2979b263239b · 2013-04-12T07:55:06.000+02:00
Give more flexibility to define configs that can be interpreted by make, e.g. to
define fallback values of configs like in the example below.

Before this change, the config lines:
 #define CONFIG_SPL_MAX_SIZE	2048
 #define CONFIG_SPL_PAD_TO	CONFIG_SPL_MAX_SIZE
would have been changed in autoconfig.mk into:
 CONFIG_SPL_MAX_SIZE=2048
 CONFIG_SPL_PAD_TO="CONFIG_SPL_MAX_SIZE"

Hence, a make recipe using as an argument to $(OBJCOPY):
 --pad-to=$(CONFIG_SPL_PAD_TO)
would have issued:
 --pad-to="CONFIG_SPL_MAX_SIZE"
which means nothing for $(OBJCOPY) and makes it fail.

Thanks to this change, the config lines above are changed in autoconfig.mk into:
 CONFIG_SPL_MAX_SIZE=2048
 CONFIG_SPL_PAD_TO=$(CONFIG_SPL_MAX_SIZE)

Hence, the make recipe above now issues:
 --pad-to=2048
as expected from the defined config.

Signed-off-by: Benoît Thébaudeau &lt;benoit.thebaudeau@advansee.com&gt;
Reviewed-by: Tom Rini &lt;trini@ti.com&gt;
diff --git a/tools/scripts/define2mk.sed b/tools/scripts/define2mk.sed
@@ -24,6 +24,8 @@
 	s/="\([0-9][0-9]*\)"/=\1/;
 	# ... and from hex numbers
 	s/="\(0[Xx][0-9a-fA-F][0-9a-fA-F]*\)"/=\1/;
+	# ... and from configs defined from other configs
+	s/="\(CONFIG_[A-Za-z0-9_][A-Za-z0-9_]*\)"/=$(\1)/;
 	# Change '1' and empty values to "y" (not perfect, but
 	# supports conditional compilation in the makefiles
 	s/=$/=y/;
