[PATCH 1/2] kbuild: export whether we are cross compiling

[PATCH 1/2] kbuild: export whether we are cross compiling

[Ahmad Fatoum]

scripts/kconfig makes use of this variable to inform whether the local
system's config should be used when no config exists.

Set it in barebox like Linux does.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 Makefile | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Makefile b/Makefile
index 9ef07ba34457..760fd7381ece 100644
--- a/Makefile
+++ b/Makefile
@@ -368,6 +368,11 @@ ifeq ($(ARCH),um)
        SRCARCH := sandbox
 endif
 
+export cross_compiling :=
+ifneq ($(SRCARCH),$(SUBARCH))
+cross_compiling := 1
+endif
+
 KCONFIG_CONFIG	?= .config
 
 PKG_CONFIG ?= pkg-config
-- 
2.39.5

[PATCH 2/2] kbuild: override host system KCONFIG_DEFCONFIG_LIST

[Ahmad Fatoum]

KCONFIG_DEFCONFIG_LIST contains some default locations where a Kernel
config can be found (e.g. /boot/config-$(uname -r)).

Currently, if a config is found in these default locations, it's used as
initial config for barebox as well, which doesn't work well, because
barebox architecture symbols defer quite a bit from the Linux ones.

Let's therefore set the make variable to an empty string to avoid this
issue.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index 760fd7381ece..5433927ed197 100644
--- a/Makefile
+++ b/Makefile
@@ -602,10 +602,10 @@ include $(srctree)/arch/$(SRCARCH)/Makefile
 export KBUILD_DEFCONFIG CC_VERSION_TEXT
 
 config: outputmakefile scripts_basic FORCE
-	$(Q)$(MAKE) $(build)=scripts/kconfig $@
+	$(Q)$(MAKE) $(build)=scripts/kconfig KCONFIG_DEFCONFIG_LIST= $@
 
 %config: outputmakefile scripts_basic FORCE
-	$(Q)$(MAKE) $(build)=scripts/kconfig $@
+	$(Q)$(MAKE) $(build)=scripts/kconfig KCONFIG_DEFCONFIG_LIST= $@
 
 else #!config-build
 # ===========================================================================
-- 
2.39.5

Re: [PATCH 1/2] kbuild: export whether we are cross compiling

[Sascha Hauer]

On Thu, 13 Mar 2025 07:37:26 +0100, Ahmad Fatoum wrote:
> scripts/kconfig makes use of this variable to inform whether the local
> system's config should be used when no config exists.
> 
> Set it in barebox like Linux does.
> 
> 

Applied, thanks!

[1/2] kbuild: export whether we are cross compiling
      https://git.pengutronix.de/cgit/barebox/commit/?id=c42de0901bd7 (link may not be stable)
[2/2] kbuild: override host system KCONFIG_DEFCONFIG_LIST
      https://git.pengutronix.de/cgit/barebox/commit/?id=2b32c64a9f08 (link may not be stable)

Best regards,
-- 
Sascha Hauer <s.hauer@pengutronix.de>