MIPS: generic: Allow filtering enabled boards by requirements
Up until now when configuring a generic kernel all board config
fragments have been merged by default unless boards are explicitly
selected by the user specifying BOARDS=.
In many cases this is sub-optimal, since some boards don't make sense to
include in some kernels. For example the MIPS SEAD-3 development board
has only ever been used with 32 bit CPUs, so including support for the
SEAD-3 in a 64 bit kernel is wasteful.
This patch introduces support for specifying requirements in board
config fragments, using comments formatted like so:
# require CONFIG_BLA=y
For example the SEAD-3 board could specify that it should only be merged
for 32 bit kernels using a requirement line like the following:
# require CONFIG_32BIT=y
A new generic-board-config.sh script is introduced to handle selecting
the board config fragments to merge & calling merge_config.sh to merge
them. In order to allow requirements to check Kconfig symbols that are
implicitly selected, rather than explicitly specified by
generic_defconfig or one of the ISA config fragments, an intermediate
.config file is saved & used as a reference when checking requirements.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16943/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/Makefile b/arch/mips/Makefile
index 38360f7..0e0aa64 100644
--- a/arch/mips/Makefile
+++ b/arch/mips/Makefile
@@ -500,8 +500,14 @@
.PHONY: $(generic_defconfigs)
$(generic_defconfigs):
$(Q)$(CONFIG_SHELL) $(srctree)/scripts/kconfig/merge_config.sh \
- -m -O $(objtree) $(srctree)/arch/$(ARCH)/configs/generic_defconfig $^ \
- $(foreach board,$(BOARDS),$(generic_config_dir)/board-$(board).config)
+ -m -O $(objtree) $(srctree)/arch/$(ARCH)/configs/generic_defconfig $^ | \
+ grep -Ev '^#'
+ $(Q)cp $(KCONFIG_CONFIG) $(objtree)/.config.$@
+ $(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig \
+ KCONFIG_CONFIG=$(objtree)/.config.$@ >/dev/null
+ $(Q)$(CONFIG_SHELL) $(srctree)/arch/$(ARCH)/tools/generic-board-config.sh \
+ $(srctree) $(objtree) $(objtree)/.config.$@ $(KCONFIG_CONFIG) \
+ "$(origin BOARDS)" $(BOARDS)
$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
#