Move scripts/Makefile.<arch>preparch to arch/<arch>

Follow the model of the Linux kernel for adding arch
specific CFLAGS by using the Makefile and Kbuild combination
in the arch/<arch> directory.

This will also allow adding architecture specific targets and is
easy to maintain when alongside the architecture.

Change-Id: If51a78e8845baa71d9090c4a4f49fcd013354840
Signed-off-by: Anas Nashif <anas.nashif@intel.com>

Makefile

@@ -12,10 +12,12 @@ export SOURCE_DIR PROJECT MDEF_FILE KLIBC_DIR
 # More info can be located in ./README
 # Comments in this file are targeted only to the developer, do not
 # expect to learn how to build the kernel reading this file.
+#
 
-# Do not use make's built-in rules and variables
+# o Do not use make's built-in rules and variables
 #   (this increases performance and avoids hard-to-debug behaviour);
-MAKEFLAGS += -rR
+# o Look for make include files relative to root of kernel src
+MAKEFLAGS += -rR --include-dir=$(CURDIR)
 
 # Avoid funny character set dependencies
 unexport LC_ALL
@@ -561,9 +563,10 @@ include/config/auto.conf: ;
 endif # $(dot-config)
 
 
-#File that includes all prepare special embedded architecture targets.
+# File that includes all prepare special embedded architecture targets.
 include $(srctree)/scripts/Makefile.preparch
-sinclude $(srctree)/scripts/Makefile.$(SRCARCH).preparch
+
+
 ifdef ZEPHYR_GCC_VARIANT
 include $(srctree)/scripts/Makefile.toolchain.$(ZEPHYR_GCC_VARIANT)
 else
@@ -589,6 +592,8 @@ QEMU		= $(QEMU_BIN_PATH)/$(QEMU_$(SRCARCH))
 # Defaults to zephyr, but the arch makefile usually adds further targets
 all: zephyr
 
+include arch/$(SRCARCH)/Makefile
+
 ifdef CONFIG_READABLE_ASM
 # Disable optimizations that make assembler listings hard to read.
 # reorder blocks reorders the control in the function
@@ -599,8 +604,6 @@ KBUILD_CFLAGS += $(call cc-option,-fno-reorder-blocks,) \
                  $(call cc-option,-fno-partial-inlining)
 endif
 
-ISA_FLAG=$(ISA_FLAG_$(SRCARCH))
-
 STACK_CANARIES_FLAG_y = $(call cc-option,-fstack-protector-all,)
 STACK_CANARIES_FLAG_  = $(call cc-option,-fno-stack-protector,)
 STACK_CANARIES_FLAG = $(STACK_CANARIES_FLAG_$(CONFIG_STACK_CANARIES))
@@ -652,7 +655,6 @@ export x86_FLAGS arm_FLAGS arc_FLAGS LDFLAG_LINKERCMD OUTPUT_FORMAT OUTPUT_ARCH
 ARCHFLAGS = $($(SRCARCH)_FLAGS)
 
 KBUILD_CFLAGS   += $(SSE_FP_MATH_FLAG) \
-		$(ISA_FLAG) \
 		$(STACK_CANARIES_FLAG) \
 		$(ARCHFLAGS)
 
@@ -661,7 +663,7 @@ KBUILD_CFLAGS 	+= $(call cc-option, -femit-struct-debug-baseonly) \
 		   $(call cc-option,-fno-var-tracking)
 endif
 KBUILD_CFLAGS += $(CFLAGS)
-KBUILD_AFLAGS += $(ARCHFLAGS) $(ISA_FLAG)
+KBUILD_AFLAGS += $(ARCHFLAGS)
 KBUILD_AFLAGS += $(CFLAGS)
 
 ifdef CONFIG_FUNCTION_TRACER

arch/arc/Kbuild

@@ -0,0 +1,8 @@
+ccflags-y +=-I$(srctree)/arch/arc/platforms/$(strip $(CONFIG_PLATFORM))
+asflags-y +=-I$(srctree)/arch/arc/platforms/$(strip $(CONFIG_PLATFORM))
+
+obj-y = core/
+
+obj-y += prep_c.o \
+         reset.o \
+         vector_table.o

arch/arc/Makefile

@@ -1,8 +1,9 @@
-ccflags-y +=-I$(srctree)/arch/arc/platforms/$(strip $(CONFIG_PLATFORM))
-asflags-y +=-I$(srctree)/arch/arc/platforms/$(strip $(CONFIG_PLATFORM))
 
-obj-y = core/
 
-obj-y += prep_c.o \
+KBUILD_CFLAGS += $(call cc-option,-ffunction-sections,) $(call cc-option,-fdata-sections,)
-         reset.o \
+cflags-$(CONFIG_LTO) = $(call cc-option,-flto,)
-         vector_table.o
+cflags-$(CPU_ARCEM4) = $(call cc-option,-mARCv2EM) \
+			 $(call cc-option,-mav2em,$(call cc-option,-mno-sdata))
+
+KBUILD_CFLAGS += $(cflags-y)
+

arch/arm/Kbuild

@@ -0,0 +1,4 @@
+obj-y = core/
+
+obj-$(CONFIG_PLATFORM_FSL_FRDM_K64F) += platforms/fsl_frdm_k64f/
+obj-$(CONFIG_PLATFORM_TI_LM3S6965) += platforms/ti_lm3s6965/

arch/arm/Makefile

@@ -1,4 +1,21 @@
-obj-y = core/
 
-obj-$(CONFIG_PLATFORM_FSL_FRDM_K64F) += platforms/fsl_frdm_k64f/
+
-obj-$(CONFIG_PLATFORM_TI_LM3S6965) += platforms/ti_lm3s6965/
+KBUILD_CFLAGS += $(call cc-option,-ffunction-sections,) $(call cc-option,-fdata-sections,)
+
+arch-$(CONFIG_CPU_CORTEX_M3) += $(call cc-option,-mthumb -mcpu=cortex-m3) \
+		$(call cc-option,-mthumb -march=armv7-m)
+arch-$(CONFIG_CPU_CORTEX_M4) += $(call cc-option,-mthumb -mcpu=cortex-m4) \
+		$(call cc-option,-mthumb -march=armv7e-m)
+
+cflags-$(CONFIG_LTO) = $(call cc-option,-flto,)
+
+KBUILD_CFLAGS += $(cflags-y) $(arch-y)
+KBUILD_AFLAGS += $(arch-y)
+
+
+QEMU_CPU_TYPE_arm = cortex-m3
+QEMU_FLAGS_arm = -cpu  $(QEMU_CPU_TYPE_arm) \
+		-machine lm3s6965evb -nographic
+QEMU_arm = qemu-system-arm
+
+export QEMU_FLAGS_arm QEMU_arm

arch/x86/Kbuild

@@ -0,0 +1,3 @@
+obj-y += core/
+obj-$(CONFIG_PLATFORM_IA32_PCI) += platforms/ia32_pci/
+obj-$(CONFIG_PLATFORM_IA32) += platforms/ia32/

arch/x86/Makefile

@@ -1,3 +1,34 @@
-obj-y += core/
+
-obj-$(CONFIG_PLATFORM_IA32_PCI) += platforms/ia32_pci/
+
-obj-$(CONFIG_PLATFORM_IA32) += platforms/ia32/
+PERF_OPT=$(if $(filter -Os,$(KBUILD_CFLAGS)),,y)
+
+cflags-y += $(call cc-option,-ffunction-sections,) $(call cc-option,-fdata-sections,)
+cflags-$(PERF_OPT) += $(call cc-option,-mpreferred-stack-boundary=2)
+cflags-$(PERF_OPT) += -DPERF_OPT
+cflags-$(CONFIG_LTO) += $(call cc-option,-flto,)
+
+
+ifneq ($(CONFIG_PLATFORM_IA32_PCI),y)
+iSSE_FP_MATH_ = -mno-sse
+iSSE_FP_MATH  = ${iSSE_FP_MATH_${CONFIG_SSE_FP_MATH}}
+endif
+cflags-y += $(iSSE_FP_MATH)
+
+arch-$(CONFIG_CPU_ATOM) += $(call cc-option,-march=atom) \
+	$(call cc-option,-mtune=atom,$(call cc-option,-mtune=generic))
+arch-$(CONFIG_CPU_MINUTEIA) += $(call cc-option,-march=pentium)
+
+KBUILD_CFLAGS += $(cflags-y) $(arch-y)
+KBUILD_AFLAGS += $(arch-y)
+
+
+QEMU_BIOS ?= /usr/share/qemu
+QEMU_CPU_TYPE_x86 = qemu32
+QEMU_FLAGS_x86 = -m 32 -cpu $(QEMU_CPU_TYPE_x86) \
+		-no-reboot -nographic -display none -net none \
+		-clock dynticks -no-acpi -balloon none \
+		-L $(QEMU_BIOS) -bios bios.bin \
+		-machine type=pc-0.14
+QEMU_x86 = qemu-system-i386
+
+export QEMU_FLAGS_x86 QEMU_x86 QEMU_CPU_TYPE_x86

scripts/Makefile.arc.preparch

@@ -1,6 +0,0 @@
-LTO_FLAG-y = $(call cc-option,-flto,)
-SECTION_GC_FLAG = $(call cc-option,-ffunction-sections,) $(call cc-option,-fdata-sections,)
-
-arc_FLAGS += -mARCv2EM -mav2em -mno-sdata
-
-export ISA_FLAG_arc

scripts/Makefile.arm.preparch

@@ -1,18 +0,0 @@
-LTO_FLAG-y = $(call cc-option,-flto,)
-SECTION_GC_FLAG = $(call cc-option,-ffunction-sections,) $(call cc-option,-fdata-sections,)
-arm_FLAGS = $(call cc-option,-mthumb,)
-ifeq ($(CONFIG_CPU_CORTEX_M3),y)
-arm_FLAGS += -mcpu=cortex-m3 -march=armv7-m
-endif
-ifeq ($(CONFIG_CPU_CORTEX_M4),y)
-arm_FLAGS += -mcpu=cortex-m4 -march=armv7e-m
-endif
-arm_FLAGS += $(SECTION_GC_FLAG)
-arm_FLAGS += $(LTO_FLAG-$(CONFIG_LTO))
-
-QEMU_CPU_TYPE_arm = cortex-m3
-QEMU_FLAGS_arm = -cpu  $(QEMU_CPU_TYPE_arm) \
-		-machine lm3s6965evb -nographic
-QEMU_arm = qemu-system-arm
-
-export QEMU_FLAGS_arm QEMU_arm

scripts/Makefile.x86.preparch

@@ -1,37 +0,0 @@
-
-
-PERF_OPT_FLAG-y = -DPERF_OPT
-ALIGN_STACK_FLAG- = -mpreferred-stack-boundary=2
-SECTION_GC_FLAG = $(call cc-option,-ffunction-sections,) $(call cc-option,-fdata-sections,)
-LTO_FLAG-y = $(call cc-option,-flto,)
-
-PERF_OPT=$(if $(filter -Os,$(KBUILD_CFLAGS)),,y)
-PERF_OPT_FLAG = $(PERF_OPT_FLAG-$(PERF_OPT))
-
-ALIGN_STACK_FLAG = $(ALIGN_STACK_FLAG-$(PERF_OPT))
-LTO_FLAG = $(LTO_FLAG-$(CONFIG_LTO))
-ifneq ($(CONFIG_PLATFORM_IA32_PCI),y)
-iSSE_FP_MATH_ ?= -mno-sse
-iSSE_FP_MATH  ?= ${iSSE_FP_MATH_${CONFIG_SSE_FP_MATH}}
-endif
-x86_FLAGS += $(ALIGN_STACK_FLAG)
-x86_FLAGS += $(SECTION_GC_FLAG)
-x86_FLAGS += $(LTO_FLAG)
-x86_FLAGS += $(LTO_FLAG)
-x86_FLAGS += $(PERF_OPT_FLAG)
-x86_FLAGS += $(iSSE_FP_MATH)
-
-ISA_FLAG_quark-$(CONFIG_CPU_MINUTEIA) = -march=pentium
-ISA_FLAG_atom-$(CONFIG_CPU_ATOM) = -march=atom -mtune=atom
-ISA_FLAG_x86 = $(strip $(ISA_FLAG_quark-y) $(ISA_FLAG_atom-y))
-
-QEMU_BIOS ?= /usr/share/qemu
-QEMU_CPU_TYPE_x86 = qemu32
-QEMU_FLAGS_x86 = -m 32 -cpu $(QEMU_CPU_TYPE_x86) \
-		-no-reboot -nographic -display none -net none \
-		-clock dynticks -no-acpi -balloon none \
-		-L $(QEMU_BIOS) -bios bios.bin \
-		-machine type=pc-0.14
-QEMU_x86 = qemu-system-i386
-
-export ISA_FLAG_x86 QEMU_FLAGS_x86 QEMU_x86 QEMU_CPU_TYPE_x86