HV: make: skip duplicated PLATFORM= on command line

Since .config has PLATFORM now, it is expected that the PLATFORM= command line
option is no longer necessary as long as a proper .config exists.

This patch implements this expectation. Now the platform to be selected is
determined by the following steps.

    1. If PLATFORM= is provided on the command line, the specified value is
       used.
    2. If there is no PLATFORM= on the command line and PLATFORM is defined in
       config.mk, its value is used.
    3. If neither PLATFORM= on the command line nor config.mk is available, a
       predefined default value is used.

v1 -> v2:

    * 'make oldconfig' should not pass CONFIG_xxx to the script since config.mk
      can be out-dated.
    * Change the default value of PLATFORM to SBL for backward compatibility of
      'make all'.

Signed-off-by: Junjie Mao <junjie.mao@intel.com>
Acked-by: Anthony Xu <anthony.xu@intel.com>
Acked-by: Geoffroy VanCutsem <geoffroy.vancutsem@intel.com>

hypervisor/Makefile

@@ -18,7 +18,6 @@ GCC_MINOR=$(shell echo __GNUC_MINOR__ | $(CC) -E -x c - | tail -n 1)
 STACK_PROTECTOR := 1
 
 BASEDIR := $(shell pwd)
-PLATFORM ?= sbl
 HV_OBJDIR ?= $(CURDIR)/build
 HV_FILE := acrn
 
@@ -75,7 +74,7 @@ INCLUDE_PATH += include/debug
 INCLUDE_PATH += include/public
 INCLUDE_PATH += include/common
 INCLUDE_PATH += bsp/include
-INCLUDE_PATH += bsp/$(PLATFORM)/include/bsp
+INCLUDE_PATH += bsp/$(CONFIG_PLATFORM)/include/bsp
 INCLUDE_PATH += boot/include
 INCLUDE_PATH += $(HV_OBJDIR)/include
 
@@ -146,14 +145,14 @@ ifdef STACK_PROTECTOR
 C_SRCS += common/stack_protector.c
 endif
 
-C_SRCS += bsp/$(PLATFORM)/vm_description.c
+C_SRCS += bsp/$(CONFIG_PLATFORM)/vm_description.c
-C_SRCS += bsp/$(PLATFORM)/$(PLATFORM).c
+C_SRCS += bsp/$(CONFIG_PLATFORM)/$(CONFIG_PLATFORM).c
-C_SRCS += bsp/$(PLATFORM)/platform_acpi_info.c
+C_SRCS += bsp/$(CONFIG_PLATFORM)/platform_acpi_info.c
 
-ifeq ($(PLATFORM),uefi)
+ifeq ($(CONFIG_PLATFORM),uefi)
-C_SRCS += bsp/$(PLATFORM)/cmdline.c
+C_SRCS += bsp/$(CONFIG_PLATFORM)/cmdline.c
 else
-ifeq ($(PLATFORM), sbl)
+ifeq ($(CONFIG_PLATFORM), sbl)
 C_SRCS += boot/sbl/multiboot.c
 C_SRCS += boot/sbl/hob_parse.c
 endif
@@ -180,13 +179,13 @@ endif
 S_OBJS := $(patsubst %.S,$(HV_OBJDIR)/%.o,$(S_SRCS))
 
 DISTCLEAN_OBJS := $(shell find $(BASEDIR) -name '*.o')
-VERSION := bsp/$(PLATFORM)/include/bsp/version.h
+VERSION := bsp/$(CONFIG_PLATFORM)/include/bsp/version.h
 
 .PHONY: all
 all: $(VERSION) $(HV_OBJDIR)/$(HV_FILE).32.out $(HV_OBJDIR)/$(HV_FILE).bin
 	rm -f $(VERSION)
 
-ifeq ($(PLATFORM), uefi)
+ifeq ($(CONFIG_PLATFORM), uefi)
 all: efi
 .PHONY: efi
 efi: $(HV_OBJDIR)/$(HV_FILE).bin
@@ -197,7 +196,7 @@ install: efi
 	make -C bsp/uefi/efi HV_OBJDIR=$(HV_OBJDIR) RELEASE=$(RELEASE) install
 endif
 
-ifeq ($(PLATFORM), sbl)
+ifeq ($(CONFIG_PLATFORM), sbl)
 install: $(VERSION) $(HV_OBJDIR)/$(HV_FILE).32.out
 	install -D $(HV_OBJDIR)/$(HV_FILE).32.out $(DESTDIR)/usr/lib/acrn/$(HV_FILE).sbl
 endif

hypervisor/arch/x86/Kconfig

@@ -1,6 +1,6 @@
 choice
 	prompt "Platform"
-	default PLATFORM_UEFI
+	default PLATFORM_SBL
 
 config PLATFORM_UEFI
 	bool "UEFI"
@@ -11,6 +11,11 @@ config PLATFORM_SBL
 
 endchoice
 
+config PLATFORM
+	string
+	default "uefi" if PLATFORM_UEFI
+	default "sbl" if PLATFORM_SBL
+
 config NR_IOAPICS
 	int "Maximum number of IOAPICs supported"
 	default 1

hypervisor/scripts/kconfig/kconfig.mk

@@ -1,3 +1,18 @@
+# usage: override_config <symbol> <default>
+#
+# Given a configuration symbol (without the CONFIG_ prefix), this macro
+# overrides its value as follows.
+#    1. If a value is specified from command line, that value is used.
+#    2. If neither config.mk nor the command line specifies a value, the given
+#       default is used.
+define override_config =
+ifdef $(1)
+CONFIG_$(1) := $($(1))
+else ifndef CONFIG_$(1)
+CONFIG_$(1) := $(2)
+endif
+endef
+
 HV_CONFIG := .config
 HV_DEFCONFIG := defconfig
 HV_CONFIG_H := include/config.h
@@ -5,6 +20,9 @@ HV_CONFIG_MK := include/config.mk
 
 KCONFIG_DIR := $(BASEDIR)/../scripts/kconfig
 
+-include $(HV_OBJDIR)/$(HV_CONFIG_MK)
+$(eval $(call override_config,PLATFORM,sbl))
+
 $(eval $(call check_dep_exec,python3,KCONFIG_DEPS))
 $(eval $(call check_dep_exec,pip3,KCONFIG_DEPS))
 $(eval $(call check_dep_py3lib,kconfiglib,KCONFIG_DEPS))
@@ -28,28 +46,35 @@ $(HV_OBJDIR)/$(HV_CONFIG_H): $(HV_OBJDIR)/$(HV_CONFIG)
 .PHONY: defconfig
 defconfig: $(KCONFIG_DEPS)
 	@mkdir -p $(HV_OBJDIR)
-	@python3 $(KCONFIG_DIR)/defconfig.py Kconfig arch/x86/configs/$(PLATFORM).config $(HV_OBJDIR)/$(HV_CONFIG)
+	@python3 $(KCONFIG_DIR)/defconfig.py Kconfig \
+		arch/x86/configs/$(CONFIG_PLATFORM).config \
+		$(HV_OBJDIR)/$(HV_CONFIG)
 
 # Use silentoldconfig to forcefully update the current .config, or generate a
 # new one if no previous .config exists. This target can be used as a
 # prerequisite of all the others to make sure that the .config is consistent
 # even it has been modified manually before.
+#
+# Note: Should not pass CONFIG_xxx to silentoldconfig here because config.mk can
+# be out-dated.
 .PHONY: oldconfig
 oldconfig: $(KCONFIG_DEPS)
 	@mkdir -p $(HV_OBJDIR)
-	@python3 $(KCONFIG_DIR)/silentoldconfig.py Kconfig $(HV_OBJDIR)/$(HV_CONFIG) PLATFORM_$(shell echo $(PLATFORM) | tr a-z A-Z)=y
+	@python3 $(KCONFIG_DIR)/silentoldconfig.py Kconfig \
+		$(HV_OBJDIR)/$(HV_CONFIG) \
+		PLATFORM_$(shell echo $(PLATFORM) | tr a-z A-Z)=y
 
 # Minimize the current .config. This target can be used to generate a defconfig
 # for future use.
 .PHONY: minimalconfig
 minimalconfig: $(HV_OBJDIR)/$(HV_CONFIG)
-	@python3 $(KCONFIG_DIR)/minimalconfig.py Kconfig $(HV_OBJDIR)/$(HV_CONFIG) $(HV_OBJDIR)/$(HV_DEFCONFIG)
+	@python3 $(KCONFIG_DIR)/minimalconfig.py Kconfig \
+		$(HV_OBJDIR)/$(HV_CONFIG) \
+		$(HV_OBJDIR)/$(HV_DEFCONFIG)
 
 $(eval $(call check_dep_exec,menuconfig,MENUCONFIG_DEPS))
 export KCONFIG_CONFIG := $(HV_OBJDIR)/$(HV_CONFIG)
 menuconfig: $(MENUCONFIG_DEPS) $(HV_OBJDIR)/$(HV_CONFIG)
 	@python3 $(shell which menuconfig) Kconfig
 
--include $(HV_OBJDIR)/$(HV_CONFIG_MK)
-
 CFLAGS += -include $(HV_OBJDIR)/$(HV_CONFIG_H)

scripts/kconfig/silentoldconfig.py

@@ -44,7 +44,7 @@ def main():
         if sym_val.find("=") == -1:
             continue
         sym_name, val = sym_val.split("=")[:2]
-        if sym_name in kconfig.syms.keys():
+        if sym_name in kconfig.syms.keys() and val:
             cmdline_conf[sym_name] = val
 
     # Check if the old .config conflicts with those specified on cmdline