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>

Makefile

@@ -503,6 +503,7 @@ autoconf_is_current := $(if $(wildcard $(KCONFIG_CONFIG)),$(shell find . \
 		-path ./include/config/auto.conf -newer $(KCONFIG_CONFIG)))
 ifneq ($(autoconf_is_current),)
 include $(srctree)/config.mk
+include $(srctree)/arch/$(ARCH)/Makefile
 endif
 
 # If board code explicitly specified LDSCRIPT or CONFIG_SYS_LDSCRIPT, use
@@ -601,17 +602,11 @@ c_flags := $(KBUILD_CFLAGS) $(cpp_flags)
 #########################################################################
 # U-Boot objects....order is important (i.e. start must be first)
 
-head-y := $(CPUDIR)/start.o
-head-$(CONFIG_4xx) += arch/powerpc/cpu/ppc4xx/resetvec.o
-head-$(CONFIG_MPC85xx) += arch/powerpc/cpu/mpc85xx/resetvec.o
-
 HAVE_VENDOR_COMMON_LIB = $(if $(wildcard $(srctree)/board/$(VENDOR)/common/Makefile),y,n)
 
 libs-y += lib/
 libs-$(HAVE_VENDOR_COMMON_LIB) += board/$(VENDOR)/common/
-libs-y += $(CPUDIR)/
 libs-$(CONFIG_OF_EMBED) += dts/
-libs-y += arch/$(ARCH)/lib/
 libs-y += fs/
 libs-y += net/
 libs-y += disk/
@@ -651,17 +646,6 @@ libs-$(CONFIG_HAS_POST) += post/
 libs-y += test/
 libs-y += test/dm/
 
-ifneq (,$(filter $(SOC), mx25 mx27 mx5 mx6 mx31 mx35 mxs vf610))
-libs-y += arch/$(ARCH)/imx-common/
-endif
-
-ifneq (,$(filter $(SOC), armada-xp kirkwood))
-libs-y += arch/$(ARCH)/mvebu-common/
-endif
-
-libs-$(CONFIG_ARM) += arch/arm/cpu/
-libs-$(CONFIG_PPC) += arch/powerpc/cpu/
-
 libs-y += $(if $(BOARDDIR),board/$(BOARDDIR)/)
 
 libs-y := $(sort $(libs-y))

arch/arc/Makefile

+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+head-y := arch/arc/cpu/$(CPU)/start.o
+
+libs-y += arch/arc/cpu/$(CPU)/
+libs-y += arch/arc/lib/

arch/arm/Makefile

+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+head-y := arch/arm/cpu/$(CPU)/start.o
+
+ifeq ($(CONFIG_SPL_BUILD),y)
+ifneq ($(CONFIG_SPL_START_S_PATH),)
+head-y := $(CONFIG_SPL_START_S_PATH:"%"=%)/start.o
+endif
+endif
+
+libs-y += arch/arm/cpu/$(CPU)/
+libs-y += arch/arm/cpu/
+libs-y += arch/arm/lib/
+
+ifeq ($(CONFIG_SPL_BUILD),y)
+ifneq (,$(CONFIG_MX23)$(CONFIG_MX35)$(filter $(SOC), mx25 mx27 mx5 mx6 mx31 mx35))
+libs-y += arch/arm/imx-common/
+endif
+else
+ifneq (,$(filter $(SOC), mx25 mx27 mx5 mx6 mx31 mx35 mxs vf610))
+libs-y += arch/arm/imx-common/
+endif
+endif
+
+ifneq (,$(filter $(SOC), armada-xp kirkwood))
+libs-y += arch/arm/mvebu-common/
+endif

arch/avr32/Makefile

+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+head-y := arch/avr32/cpu/start.o
+
+libs-y += arch/avr32/cpu/
+libs-y += arch/avr32/lib/

arch/blackfin/Makefile

+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+head-y := arch/blackfin/cpu/start.o
+
+libs-y += arch/blackfin/cpu/
+libs-y += arch/blackfin/lib/

arch/m68k/Makefile

+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+head-y := arch/m68k/cpu/$(CPU)/start.o
+
+libs-y += arch/m68k/cpu/$(CPU)/
+libs-y += arch/m68k/lib/

arch/microblaze/Makefile

+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+head-y := arch/microblaze/cpu/start.o
+
+libs-y += arch/microblaze/cpu/
+libs-y += arch/microblaze/lib/

arch/mips/Makefile

+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+head-y := arch/mips/cpu/$(CPU)/start.o
+
+libs-y += arch/mips/cpu/$(CPU)/
+libs-y += arch/mips/lib/

arch/nds32/Makefile

+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+head-y := arch/nds32/cpu/$(CPU)/start.o
+
+libs-y += arch/nds32/cpu/$(CPU)/
+libs-y += arch/nds32/lib/

arch/nios2/Makefile

+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+head-y := arch/nios2/cpu/start.o
+
+libs-y += arch/nios2/cpu/
+libs-y += arch/nios2/lib/

arch/openrisc/Makefile

+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+head-y := arch/openrisc/cpu/start.o
+
+libs-y += arch/openrisc/cpu/
+libs-y += arch/openrisc/lib/

arch/powerpc/Makefile

+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+head-y := arch/powerpc/cpu/$(CPU)/start.o
+head-$(CONFIG_4xx) += arch/powerpc/cpu/ppc4xx/resetvec.o
+head-$(CONFIG_MPC85xx) += arch/powerpc/cpu/mpc85xx/resetvec.o
+
+libs-y += arch/powerpc/cpu/$(CPU)/
+libs-y += arch/powerpc/cpu/
+libs-y += arch/powerpc/lib/

arch/sandbox/Makefile

+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+head-y := arch/sandbox/cpu/start.o
+
+libs-y += arch/sandbox/cpu/
+libs-y += arch/sandbox/lib/

arch/sh/Makefile

+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+head-y := arch/sh/cpu/$(CPU)/start.o
+
+libs-y += arch/sh/cpu/$(CPU)/
+libs-y += arch/sh/lib/

arch/sparc/Makefile

+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+head-y := arch/sparc/cpu/$(CPU)/start.o
+
+libs-y += arch/sparc/cpu/$(CPU)/
+libs-y += arch/sparc/lib/

arch/x86/Makefile

+#
+# 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/

scripts/Makefile.spl

@@ -34,6 +34,7 @@ SPL_BIN := u-boot-spl
 endif
 
 include $(srctree)/config.mk
+include $(srctree)/arch/$(ARCH)/Makefile
 
 # Enable garbage collection of un-used sections for SPL
 KBUILD_CFLAGS += -ffunction-sections -fdata-sections
@@ -45,21 +46,6 @@ cpp_flags := $(KBUILD_CPPFLAGS) $(PLATFORM_CPPFLAGS) $(UBOOTINCLUDE) \
 
 HAVE_VENDOR_COMMON_LIB = $(if $(wildcard $(srctree)/board/$(VENDOR)/common/Makefile),y,n)
 
-ifdef	CONFIG_SPL_START_S_PATH
-START_PATH := $(CONFIG_SPL_START_S_PATH:"%"=%)
-else
-START_PATH := $(CPUDIR)
-endif
-
-head-y := $(START_PATH)/start.o
-head-$(CONFIG_X86) += $(START_PATH)/start16.o $(START_PATH)/resetvec.o
-head-$(CONFIG_4xx) += $(START_PATH)/resetvec.o
-head-$(CONFIG_MPC85xx) += $(START_PATH)/resetvec.o
-
-libs-y += arch/$(ARCH)/lib/
-
-libs-y += $(CPUDIR)/
-
 libs-y += $(if $(BOARDDIR),board/$(BOARDDIR)/)
 libs-$(HAVE_VENDOR_COMMON_LIB) += board/$(VENDOR)/common/
 
@@ -94,13 +80,6 @@ libs-$(CONFIG_SPL_USB_HOST_SUPPORT) += drivers/usb/host/
 libs-$(CONFIG_OMAP_USB_PHY) += drivers/usb/phy/
 libs-$(CONFIG_SPL_SATA_SUPPORT) += drivers/block/
 
-ifneq (,$(CONFIG_MX23)$(CONFIG_MX35)$(filter $(SOC), mx25 mx27 mx5 mx6 mx31 mx35))
-libs-y += arch/$(ARCH)/imx-common/
-endif
-
-libs-$(CONFIG_ARM) += arch/arm/cpu/
-libs-$(CONFIG_PPC) += arch/powerpc/cpu/
-
 head-y		:= $(addprefix $(obj)/,$(head-y))
 libs-y		:= $(addprefix $(obj)/,$(libs-y))
 u-boot-spl-dirs	:= $(patsubst %/,%,$(filter %/, $(libs-y)))