Kbuild: introduce Makefile in arch/$ARCH/

Introduce a Makefile under arch/$ARCH/ and include it in the
top Makefile (similar to Linux kernel). This allows further
refactoringi like moving architecture-specific code out of global
makefiles, deprecating config variables (CPU, CPUDIR, SOC) or
deprecating arch/$ARCH/config.mk.

In contrary to Linux kernel, U-Boot defines the ARCH variable by
Kconfig, thus the arch Makefile can only included conditionally
after the top config.mk.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Acked-by: Masahiro Yamada <yamada.m@jp.panasonic.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/arch/x86/Makefile b/arch/x86/Makefile
new file mode 100644
index 0000000000..36a601822a
--- /dev/null
+++ b/arch/x86/Makefile
@@ -0,0 +1,12 @@
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+head-y := arch/x86/cpu/start.o
+ifeq ($(CONFIG_SPL_BUILD),y)
+head-y += arch/x86/cpu/start16.o
+head-y += arch/x86/cpu/resetvec.o
+endif
+
+libs-y += arch/x86/cpu/
+libs-y += arch/x86/lib/