payloads/external/LinuxBoot: Clean up

There were some issues with the current Linuxboot Makefiles.
- multithreaded compilation didn't work, because some prerequisites
  were missing
- initramfs wasn't added for x86 qemu boot.
- riscv support was incomplete

It began with separate patches, but resulted in a clean up patch, that
is hard to separate. The most important changes are the following:
- Instead of phony targets, actual files are now used as prerequisites
- riscv can now be used as target
- initramfs works now also for x86
- instead of querying the most recent version from the internet, I set a
  known working version (because I tested it) that can be customized
  and/or upgraded in the future. The reasons:
      - querying the version from the internet requires a constant
        connection to the internet even after linux kernel is already
        build (aka subsequent builds).
      - one usually wants to use a known working version, but optionally
        still have the posibillity to choose a custom one. This patch
        introduces this possibility in its most simple form.
- I removed as much ifeq statements as possible and moved that
  responsibility to Kconfig, because they tend to make the
  Makefile less readable.

Signed-off-by: Maximilian Brune <maximilian.brune@9elements.com>
Change-Id: I25e757108e0dd473969fe5a192ad0733f1fe6286
Reviewed-on: https://review.coreboot.org/c/coreboot/+/76150
Reviewed-by: Lean Sheng Tan <sheng.tan@9elements.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

1 files changed, 28 insertions, 95 deletions

diff --git a/payloads/external/LinuxBoot/targets/linux.mk b/payloads/external/LinuxBoot/targets/linux.mk
index 12f66f7049..4156e1ee74 100644
--- a/payloads/external/LinuxBoot/targets/linux.mk
+++ b/payloads/external/LinuxBoot/targets/linux.mk
@@ -1,41 +1,20 @@
 ## SPDX-License-Identifier: GPL-2.0-only
 
-SHELL := /bin/bash
+SHELL := /bin/sh
 
-ARCH-$(CONFIG_LINUXBOOT_X86_64)=x86_64
-ARCH-$(CONFIG_LINUXBOOT_X86)=x86
-ARCH-$(CONFIG_LINUXBOOT_ARM64)=arm64
-
-TAG-$(CONFIG_LINUXBOOT_KERNEL_MAINLINE)=mainline
-TAG-$(CONFIG_LINUXBOOT_KERNEL_STABLE)=stable
-TAG-$(CONFIG_LINUXBOOT_KERNEL_LONGTERM)=longterm
-
-pwd:=$(shell pwd)
-top:=../../..
-project_dir=linuxboot
-tarball_dir:=$(project_dir)/tarball
-decompress_flag=.done
-
-OBJCOPY:=$(LINUXBOOT_CROSS_COMPILE)objcopy
+OBJCOPY:=$(CONFIG_LINUXBOOT_CROSS_COMPILE)objcopy
 KERNEL_MAKE_FLAGS = \
-	ARCH=$(ARCH-y) \
+	CROSS_COMPILE=$(CONFIG_LINUXBOOT_CROSS_COMPILE) \
+	ARCH=$(LINUX_ARCH-y) \
 	KBUILD_BUILD_USER="coreboot" \
 	KBUILD_BUILD_HOST="reproducible" \
 	KBUILD_BUILD_TIMESTAMP="$(shell perl -e 'print scalar gmtime($(SOURCE_DATE_EPOCH))')" \
 	KBUILD_BUILD_VERSION="0"
 
-ifeq ($(CONFIG_LINUXBOOT_KERNEL_CUSTOM),y)
-	kernel_version:=$(CONFIG_LINUXBOOT_KERNEL_CUSTOM_VERSION)
-else
-	kernel_version:=$(shell curl -sS -k https://www.kernel.org/feeds/kdist.xml | \
-		sed -n -e 's@.*<guid isPermaLink="false">\(.*\)</guid>.*@\1@p' | \
-		awk -F ',' '/$(TAG-y)/{ print $$3 }' | \
-		head -n 1)
-endif
-
-kernel_dir=$(project_dir)/kernel-$(subst .,_,$(kernel_version))
-kernel_tarball=linux-$(kernel_version).tar
-kernel_mirror=https://mirrors.edge.kernel.org/pub/linux/kernel
+kernel_version = $(CONFIG_LINUXBOOT_KERNEL_VERSION)
+kernel_dir = build/kernel-$(subst .,_,$(kernel_version))
+kernel_tarball = linux-$(kernel_version).tar
+kernel_mirror  = https://mirrors.edge.kernel.org/pub/linux/kernel
 
 ifeq ($(findstring x2.6.,x$(kernel_version)),x2.6.)
 kernel_mirror_path := $(kernel_mirror)/v2.6
@@ -49,81 +28,35 @@ else ifeq ($(findstring x6.,x$(kernel_version)),x6.)
 kernel_mirror_path := $(kernel_mirror)/v6.x
 endif
 
-all: kernel
-
-lookup:
-ifeq ($(kernel_version),)
-	$(error kernel version lookup failed for $(TAG-y) release)
-endif
-	@echo "    WWW        Kernel [$(TAG-y)] $(kernel_version)"
-
-fetch:
-ifneq ($(shell [[ -d "$(kernel_dir)" && -f "$(kernel_dir)/$(decompress_flag)" ]];echo $$?),0)
-	mkdir -p $(tarball_dir)
-	if [[ ! -f $(tarball_dir)/$(kernel_tarball).xz && ! -f $(tarball_dir)/$(kernel_tarball).xz ]]; then \
-	echo "    WWW        $(kernel_tarball).xz"; \
-	cd $(tarball_dir); \
-	curl -OLSs "$(kernel_mirror_path)/$(kernel_tarball).xz"; \
-	cd $(pwd); \
-	fi
-endif
+build/$(kernel_tarball).xz:
+	echo "    Test $(kernel_version)"
+	echo "    WWW        $(kernel_mirror_path)/$(kernel_tarball).xz";
+	curl -OLSs --output-dir build "$(kernel_mirror_path)/$(kernel_tarball).xz";
 
-unpack: fetch
-	if [[ -d "$(kernel_dir)" && ! -f "$(kernel_dir)/$(decompress_flag)" ]]; then \
-	rm -rf $(kernel_dir); \
-	fi
-	if [[ ! -d "$(kernel_dir)" ]]; then \
-	mkdir $(kernel_dir); \
-	echo "    XZ         $(kernel_tarball).xz"; \
-	tar xJf $(tarball_dir)/$(kernel_tarball).xz --strip 1 -C $(kernel_dir); \
-	fi
-	touch $(kernel_dir)/$(decompress_flag)
+$(kernel_dir): build/$(kernel_tarball).xz
+	echo "    XZ         $(kernel_tarball).xz";
+	mkdir $(kernel_dir);
+	tar xJf build/$(kernel_tarball).xz --strip 1 -C $(kernel_dir);
 
-$(kernel_dir)/.config: unpack
+$(kernel_dir)/.config: $(CONFIG_LINUXBOOT_KERNEL_CONFIGFILE) | $(kernel_dir)
 	@echo "    CONFIG     Linux $(kernel_version)"
-ifeq ($(CONFIG_LINUXBOOT_KERNEL_CUSTOM_CONFIG),y)
 	cp $(CONFIG_LINUXBOOT_KERNEL_CONFIGFILE) $(kernel_dir)/.config
-else
-	cp $(ARCH-y)/defconfig $(kernel_dir)/.config
-endif
 	$(MAKE) -C $(kernel_dir) $(KERNEL_MAKE_FLAGS) olddefconfig
 
-build: $(kernel_dir)/.config
+$(kernel_dir)/vmlinux : $(kernel_dir)/.config | $(kernel_dir)
 	@echo "    MAKE       Linux $(kernel_version)"
-ifeq ($(CONFIG_LINUXBOOT_KERNEL_BZIMAGE),y)
-	$(MAKE) -C $(kernel_dir) $(KERNEL_MAKE_FLAGS) CROSS_COMPILE=$(LINUXBOOT_CROSS_COMPILE) bzImage
-else
-ifeq ($(CONFIG_LINUXBOOT_KERNEL_UIMAGE),y)
-	$(MAKE) -C $(kernel_dir) $(KERNEL_MAKE_FLAGS) CROSS_COMPILE=$(LINUXBOOT_CROSS_COMPILE) vmlinux
-endif
-endif
+	echo "$(MAKE) -j 4 -C $(kernel_dir) $(KERNEL_MAKE_FLAGS) vmlinux"
+	$(MAKE) -j 4 -C $(kernel_dir) $(KERNEL_MAKE_FLAGS) vmlinux
 
-ifeq ($(CONFIG_LINUXBOOT_KERNEL_BZIMAGE),y)
-$(top)/$(CONFIG_LINUXBOOT_KERNEL): build
-	@echo "    CP         bzImage"
-	cp $(kernel_dir)/arch/x86/boot/bzImage $@
-else
-ifeq ($(CONFIG_LINUXBOOT_KERNEL_UIMAGE),y)
-$(project_dir)/target.dtb: $(top)/$(CONFIG_LINUXBOOT_DTB_FILE)
-	cp $< $@
-$(project_dir)/vmlinux.bin: $(kernel_dir)/vmlinux
+build/vmlinux.bin: $(kernel_dir)/vmlinux | build
 	$(OBJCOPY) -O binary $< $@
-$(project_dir)/vmlinux.bin.lzma: $(project_dir)/vmlinux.bin
+
+build/vmlinux.bin.lzma: build/vmlinux.bin
 	xz -c -k -f --format=lzma --lzma1=dict=1MiB,lc=3,lp=0,pb=3 $< > $@
-$(top)/$(CONFIG_LINUXBOOT_KERNEL): build $(project_dir)/vmlinux.bin.lzma $(project_dir)/target.dtb
-	cp $(project_dir)/../arm64/kernel_fdt_lzma.its $(project_dir)
-	cp $(top)/$(CONFIG_LINUXBOOT_INITRAMFS)$(CONFIG_LINUXBOOT_INITRAMFS_SUFFIX) $(project_dir)/initramfs
-	mkimage -f $(project_dir)/kernel_fdt_lzma.its $@
-else
-	$(error Kernel image format not found)
-	exit 1
-endif
-endif
 
-ifneq ($(TAG-y),)
-kernel: lookup $(top)/$(CONFIG_LINUXBOOT_KERNEL)
-else
-kernel: $(top)/$(CONFIG_LINUXBOOT_KERNEL)
-endif
+$(kernel_dir)/arch/x86/boot/bzImage: $(kernel_dir)/.config
+	@echo "    MAKE       Linux $(kernel_version)"
+	echo "$(MAKE) -C $(kernel_dir) $(KERNEL_MAKE_FLAGS) bzImage"
+	$(MAKE) -C $(kernel_dir) $(KERNEL_MAKE_FLAGS) bzImage
 
-.PHONY: all kernel build unpack fetch check
+.PHONY: kernel