Makefile: generate C configuration files at build time

This patch makes the build system of the hypervisor to cache the board and
scenario XML files in the build directory and generate C configuration
files from them at build time. The C configuration files that are cached in
the git repo is no longer used or updated. Paths to these generated files
in the prebuild Makefile is updated accordingly.

The following targets are introduced or modified.

    * defconfig: Copy default configuration XMLs to the build directory and
                 generate C configuration files.

    * oldconfig: No action.

    * menuconfig: Print a message to redirect users to use the config app
                  and exit.

    * showconfig: Print the BOARD, SCENARIO and RELEASE configured for the
                  current build.

    * update_config: No action.

    * (default): Build the hypervisor with defined configurations.

The following variables can be set on the command line to specify the
default configuration to be used.

    * BOARD: Either a name of the target board or a path to a customized
             board XML. When a board name is specified, the board XML file
             is expected to be available under
             misc/acrn-config/xmls/board-xmls.

    * SCENARIO: Either a name of the scenario of a path to a customized
                scenario XML. When a scenario name is specified, the
                scenario XML file is expected to be available under
                misc/acrn-config/xmls/config-xmls/$(BOARD).

    * BOARD_FILE: Path to the board XML file to be used. This is now
                  obsoleted as BOARD provides the same functionality.

    * SCENARIO_FILE: Path to the scenario XML file to be used. This is now
                     obsoleted as BOARD provides the same functionality.

BOARD/SCENARIO or BOARD_FILE/SCENARIO_FILE shall be used in pair, and
BOARD_FILE/SCENARIO_FILE shall point to valid files when specified. Any
violation to those constraints will stop the build with error
messages. When BOARD/SCENARIO and BOARD_FILE/SCENARIO_FILE are both defined
on the command line, the former takes precedence as the latter are to be
obsoleted.

Additionally, users can define the RELEASE variable to specify a debug or
release build. In case a previous build exists but is configured for a
different build type, the build system will automatically update the
scenario XML and rebuild the sources.

This patch also includes the following tweaks:

    1. Do not use `realpath` to process search paths for generated
       headers. `realpath` only accepts paths of existing files, while the
       directories for generated headers may not be created at the time the
       search paths are calculated.
    2. Always expect `pci_dev.c` to be in place.
    3. HV_CONFIG_* series now encodes absolute paths.

v3:
 * Do not validate BOARD_FILE/SCENARIO_FILE if BOARD/SCENARIO are given.

v2:
 * `defconfig` now also generates the C configuration files.
 * BOARD/SCENARIO now accept either board/scenario names or XML file paths.
 * Adapt to the new allocation.xml & unified.xml.
 * Cleanup names of internal variables in config.mk for brevity.

Tracked-On: #5644
Signed-off-by: Junjie Mao <junjie.mao@intel.com>

hypervisor/Makefile

@@ -19,10 +19,6 @@ HV_OBJDIR ?= $(CURDIR)/build
 HV_MODDIR ?= $(HV_OBJDIR)/modules
 HV_FILE := acrn
 
-ifeq ($(TARGET_DIR),)
-  override TARGET_DIR := $(realpath ../misc/vm_configs)
-endif
-
 LIB_MOD = $(HV_MODDIR)/lib_mod.a
 BOOT_MOD = $(HV_MODDIR)/boot_mod.a
 HW_MOD = $(HV_MODDIR)/hw_mod.a
@@ -47,20 +43,10 @@ ARCH_LDFLAGS :=
 .PHONY: default
 default: all
 
-include scripts/makefile/cfg_update.mk
+include scripts/makefile/config.mk
 
-include scripts/makefile/deps.mk
-
-include scripts/makefile/kconfig.mk
-
-#override BOARD from CONFIG_BOARD, which is specified in kconfig.mk
-override BOARD := $(shell echo $(CONFIG_BOARD) |sed 's/"//g')
-
-#override SCENARIO from CONFIG_SCENARIO, which is specified in kconfig.mk
-override SCENARIO := $(shell echo $(CONFIG_SCENARIO) |sed 's/"//g')
-
-BOARD_INFO_DIR := $(TARGET_DIR)/boards/$(BOARD)
-SCENARIO_CFG_DIR := $(TARGET_DIR)/scenarios/$(SCENARIO)
+BOARD_INFO_DIR := $(HV_CONFIG_DIR)/boards/$(BOARD)
+SCENARIO_CFG_DIR := $(HV_CONFIG_DIR)/scenarios/$(SCENARIO)
 BOARD_CFG_DIR := $(SCENARIO_CFG_DIR)/$(BOARD)
 
 include ../paths.make
@@ -147,27 +133,27 @@ ARCH_LDFLAGS +=
 ARCH_LDSCRIPT = $(HV_OBJDIR)/link_ram.ld
 ARCH_LDSCRIPT_IN = bsp/ld/link_ram.ld.in
 
-INCLUDE_PATH += include
-INCLUDE_PATH += include/lib
-INCLUDE_PATH += include/lib/crypto
-INCLUDE_PATH += include/common
-INCLUDE_PATH += include/arch/x86
-INCLUDE_PATH += include/arch/x86/boot
-INCLUDE_PATH += include/arch/x86/guest
-INCLUDE_PATH += include/arch/x86/lib
-INCLUDE_PATH += include/debug
-INCLUDE_PATH += include/public
-INCLUDE_PATH += include/dm
-INCLUDE_PATH += include/hw
-INCLUDE_PATH += boot/include
-INCLUDE_PATH += boot/include/guest
+REL_INCLUDE_PATH += include
+REL_INCLUDE_PATH += include/lib
+REL_INCLUDE_PATH += include/lib/crypto
+REL_INCLUDE_PATH += include/common
+REL_INCLUDE_PATH += include/arch/x86
+REL_INCLUDE_PATH += include/arch/x86/boot
+REL_INCLUDE_PATH += include/arch/x86/guest
+REL_INCLUDE_PATH += include/arch/x86/lib
+REL_INCLUDE_PATH += include/debug
+REL_INCLUDE_PATH += include/public
+REL_INCLUDE_PATH += include/dm
+REL_INCLUDE_PATH += include/hw
+REL_INCLUDE_PATH += boot/include
+REL_INCLUDE_PATH += boot/include/guest
+
+INCLUDE_PATH := $(realpath $(REL_INCLUDE_PATH))
 INCLUDE_PATH += $(HV_OBJDIR)/include
 INCLUDE_PATH += $(BOARD_INFO_DIR)
 INCLUDE_PATH += $(BOARD_CFG_DIR)
 INCLUDE_PATH += $(SCENARIO_CFG_DIR)
 
-override INCLUDE_PATH := $(realpath $(INCLUDE_PATH))
-
 CC ?= gcc
 AS ?= as
 AR ?= ar
@@ -266,9 +252,7 @@ endif
 VM_CFG_C_SRCS += $(BOARD_INFO_DIR)/board.c
 VM_CFG_C_SRCS += $(SCENARIO_CFG_DIR)/vm_configurations.c
 VM_CFG_C_SRCS += $(BOARD_CFG_DIR)/pt_intx.c
-ifneq (,$(wildcard $(BOARD_CFG_DIR)/pci_dev.c))
 VM_CFG_C_SRCS += $(BOARD_CFG_DIR)/pci_dev.c
-endif
 
 # virtual platform base component
 VP_BASE_C_SRCS += arch/x86/guest/vcpuid.c
@@ -342,7 +326,7 @@ BOOT_C_OBJS := $(patsubst %.c,$(HV_OBJDIR)/%.o,$(BOOT_C_SRCS))
 BOOT_S_OBJS := $(patsubst %.S,$(HV_OBJDIR)/%.o,$(BOOT_S_SRCS))
 HW_C_OBJS := $(patsubst %.c,$(HV_OBJDIR)/%.o,$(HW_C_SRCS))
 HW_S_OBJS := $(patsubst %.S,$(HV_OBJDIR)/%.o,$(HW_S_SRCS))
-VM_CFG_C_OBJS := $(patsubst %.c,$(HV_OBJDIR)/%.o,$(realpath $(VM_CFG_C_SRCS)))
+VM_CFG_C_OBJS := $(patsubst %.c,%.o,$(VM_CFG_C_SRCS))
 VP_BASE_C_OBJS := $(patsubst %.c,$(HV_OBJDIR)/%.o,$(VP_BASE_C_SRCS))
 VP_BASE_S_OBJS := $(patsubst %.S,$(HV_OBJDIR)/%.o,$(VP_BASE_S_SRCS))
 VP_DM_C_OBJS := $(patsubst %.c,$(HV_OBJDIR)/%.o,$(VP_DM_C_SRCS))
@@ -393,15 +377,15 @@ install-debug: $(HV_OBJDIR)/$(HV_FILE).map $(HV_OBJDIR)/$(HV_FILE).out
 	install -D $(HV_OBJDIR)/$(HV_FILE).map $(DESTDIR)$(libdir)/acrn/$(HV_FILE).$(BOARD).$(SCENARIO).map
 
 .PHONY: pre_build
-pre_build: $(HV_OBJDIR)/$(HV_CONFIG_H)
+pre_build: $(HV_CONFIG_H) $(HV_CONFIG_TIMESTAMP)
 	@echo "Start pre-build static check ..."
-	$(MAKE) -C $(PRE_BUILD_DIR) BOARD=$(BOARD) SCENARIO=$(SCENARIO) TARGET_DIR=$(TARGET_DIR)
+	$(MAKE) -C $(PRE_BUILD_DIR) BOARD=$(BOARD) SCENARIO=$(SCENARIO) TARGET_DIR=$(HV_CONFIG_DIR)
 	@$(HV_OBJDIR)/hv_prebuild_check.out
 	@echo "generate the binary of ACPI tables for pre-launched VMs ..."
-	python3 ../misc/acrn-config/acpi_gen/bin_gen.py --board $(BOARD) --scenario $(SCENARIO) --asl $(TARGET_DIR) --out $(HV_OBJDIR)/acpi
+	python3 ../misc/acrn-config/acpi_gen/bin_gen.py --board $(BOARD) --scenario $(SCENARIO) --asl $(HV_CONFIG_DIR) --out $(HV_OBJDIR)/acpi
 
 .PHONY: header
-header: $(VERSION) $(HV_OBJDIR)/$(HV_CONFIG_H)
+header: $(VERSION) $(HV_CONFIG_H)
 
 .PHONY: lib-mod boot-mod hw-mod vp-base-mod vp-dm-mod vp-trusty-mod vp-hcall-mod sys-init-mod
 $(LIB_MOD): $(LIB_C_OBJS) $(LIB_S_OBJS)
@@ -459,7 +443,7 @@ $(HV_OBJDIR)/$(HV_FILE).bin: $(HV_OBJDIR)/$(HV_FILE).out
 	rm -f $(UPDATE_RESULT)
 
 $(HV_OBJDIR)/$(HV_FILE).out: $(MODULES)
-	${BASH} ${LD_IN_TOOL} $(ARCH_LDSCRIPT_IN) $(ARCH_LDSCRIPT) ${HV_OBJDIR}/.config
+	${BASH} ${LD_IN_TOOL} $(ARCH_LDSCRIPT_IN) $(ARCH_LDSCRIPT) ${HV_CONFIG_MK}
 	$(CC) -Wl,-Map=$(HV_OBJDIR)/$(HV_FILE).map -o $@ $(LDFLAGS) $(ARCH_LDFLAGS) -T$(ARCH_LDSCRIPT) \
 		-Wl,--start-group $^ -Wl,--end-group
 
@@ -476,7 +460,7 @@ distclean:
 	rm -f tags TAGS cscope.files cscope.in.out cscope.out cscope.po.out GTAGS GPATH GRTAGS GSYMS
 
 PHONY: (VERSION)
-$(VERSION): $(HV_OBJDIR)/$(HV_CONFIG_H)
+$(VERSION): $(HV_CONFIG_H)
 	touch $(VERSION)
 	@COMMIT=`git rev-parse --verify --short HEAD 2>/dev/null`;\
 	DIRTY=`git diff-index --name-only HEAD`;\
@@ -511,10 +495,14 @@ $(VERSION): $(HV_OBJDIR)/$(HV_CONFIG_H)
 -include $(C_OBJS:.o=.d)
 -include $(S_OBJS:.o=.d)
 
-$(HV_OBJDIR)/%.o: %.c $(VERSION) $(HV_OBJDIR)/$(HV_CONFIG_H)
+$(HV_OBJDIR)/%.o: %.c $(VERSION) $(HV_CONFIG_H)
 	[ ! -e $@ ] && mkdir -p $(dir $@) && mkdir -p $(HV_MODDIR); \
 	$(CC) $(patsubst %, -I%, $(INCLUDE_PATH)) -I. -c $(CFLAGS) $(ARCH_CFLAGS) $< -o $@ -MMD -MT $@
 
-$(HV_OBJDIR)/%.o: %.S $(HV_OBJDIR)/$(HV_CONFIG_H)
+$(VM_CFG_C_OBJS): %.o: %.c $(VERSION) $(HV_CONFIG_H)
+	[ ! -e $@ ] && mkdir -p $(dir $@) && mkdir -p $(HV_MODDIR); \
+	$(CC) $(patsubst %, -I%, $(INCLUDE_PATH)) -I. -c $(CFLAGS) $(ARCH_CFLAGS) $< -o $@ -MMD -MT $@
+
+$(HV_OBJDIR)/%.o: %.S $(HV_CONFIG_H)
 	[ ! -e $@ ] && mkdir -p $(dir $@) && mkdir -p $(HV_MODDIR); \
 	$(CC) $(patsubst %, -I%, $(INCLUDE_PATH)) -I. $(ASFLAGS) $(ARCH_ASFLAGS) -c $< -o $@ -MMD -MT $@