From a441f9a988f65d2a5585c8c0d69f196cd9dcb8d1 Mon Sep 17 00:00:00 2001
From: Joachim Wiberg <troglobit@gmail.com>
Date: Mon, 9 May 2022 19:01:25 +0200
Subject: [PATCH] Create basic BR2_EXTERNAL, with a twist

Initial defconfig is based on Buildroot qemu_x86_64_defconfig, with a
Bootlin pre-built toolchain and a very basic qemu.sh script, generated
by a local post-image.sh, for `make run`.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
---
 .gitignore                 |  6 ++++++
 .gitmodules                |  3 +++
 Config.in                  |  0
 Makefile                   | 30 ++++++++++++++++++++++++++++
 board/common/post-image.sh | 16 +++++++++++++++
 buildroot                  |  1 +
 configs/x86_defconfig      | 41 ++++++++++++++++++++++++++++++++++++++
 external.desc              |  2 ++
 external.mk                |  0
 patches/.empty             |  0
 10 files changed, 99 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 .gitmodules
 create mode 100644 Config.in
 create mode 100644 Makefile
 create mode 100755 board/common/post-image.sh
 create mode 160000 buildroot
 create mode 100644 configs/x86_defconfig
 create mode 100644 external.desc
 create mode 100644 external.mk
 create mode 100644 patches/.empty

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 00000000..2aafd58e
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,6 @@
+*~
+.gdb_history
+/.ccache
+/dl
+/output*
+/local.mk
diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 00000000..e1d58ff5
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "buildroot"]
+	path = buildroot
+	url = https://github.com/buildroot/buildroot.git
diff --git a/Config.in b/Config.in
new file mode 100644
index 00000000..e69de29b
diff --git a/Makefile b/Makefile
new file mode 100644
index 00000000..dfa15477
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,30 @@
+export BR2_EXTERNAL := $(CURDIR)
+export PATH         := $(CURDIR)/bin:$(PATH)
+
+ARCH ?= $(shell uname -m)
+O    ?= $(CURDIR)/output
+
+config := $(O)/.config
+bmake   = $(MAKE) -C buildroot O=$(O) $1
+
+
+all: $(config) buildroot/Makefile
+	@+$(call bmake,$@)
+
+$(config):
+	@+$(call bmake,list-defconfigs)
+	@echo "ERROR: No configuration selected."
+	@echo "Please choose a configuration from the list above by running"
+	@echo "'make <board>_defconfig' before building an image."
+	@exit 1
+
+%: buildroot/Makefile
+	@+$(call bmake,$@)
+
+buildroot/Makefile:
+	@git submodule update --init
+
+run:
+	@echo "Starting Qemu  ::  Ctrl-a x -- exit | Ctrl-a c -- toggle console/monitor"
+	@(cd $(O)/images && ./qemu.sh)
+
diff --git a/board/common/post-image.sh b/board/common/post-image.sh
new file mode 100755
index 00000000..ede26e99
--- /dev/null
+++ b/board/common/post-image.sh
@@ -0,0 +1,16 @@
+#!/bin/sh
+
+# shellcheck disable=SC1090
+. "$BR2_CONFIG" 2>/dev/null
+
+cat <<-EOF >"$BINARIES_DIR/qemu.sh"
+	#!/bin/sh
+	line=\$(stty -g)
+	stty raw
+	qemu-system-x86_64 -M pc -cpu kvm64 -enable-kvm -nographic		\\
+	    -kernel bzImage -append "rootwait root=/dev/vda console=ttyS0"	\\
+	    -drive file=rootfs.ext2,if=virtio,format=raw			\\
+	    -net nic,model=virtio -net user
+	stty "\$line"
+EOF
+chmod +x "$BINARIES_DIR/qemu.sh"
diff --git a/buildroot b/buildroot
new file mode 160000
index 00000000..21ab3e72
--- /dev/null
+++ b/buildroot
@@ -0,0 +1 @@
+Subproject commit 21ab3e720c0acae2332454cf0ebdb992ac65b644
diff --git a/configs/x86_defconfig b/configs/x86_defconfig
new file mode 100644
index 00000000..6bd6510d
--- /dev/null
+++ b/configs/x86_defconfig
@@ -0,0 +1,41 @@
+# Architecture
+BR2_x86_64=y
+BR2_x86_corei7=y
+BR2_DL_DIR="$(BR2_EXTERNAL_INFIX_PATH)/dl"
+BR2_CCACHE=y
+BR2_CCACHE_DIR="$(BR2_EXTERNAL_INFIX_PATH)/.ccache"
+BR2_ENABLE_DEBUG=y
+BR2_GLOBAL_PATCH_DIR="$(BR2_EXTERNAL_INFIX_PATH)/patches"
+BR2_TOOLCHAIN_EXTERNAL=y
+BR2_TOOLCHAIN_EXTERNAL_BOOTLIN_X86_64_CORE_I7_UCLIBC_BLEEDING_EDGE=y
+
+# System
+BR2_SYSTEM_DHCP="eth0"
+BR2_TARGET_GENERIC_HOSTNAME="infix"
+BR2_TARGET_GENERIC_ISSUE="Inf/IX by KernelKit"
+
+# Filesystem
+BR2_TARGET_ROOTFS_EXT2=y
+# BR2_TARGET_ROOTFS_TAR is not set
+
+# Image
+BR2_ROOTFS_POST_BUILD_SCRIPT="board/qemu/x86_64/post-build.sh"
+
+# Image
+BR2_ROOTFS_POST_IMAGE_SCRIPT="board/qemu/post-image.sh $(BR2_EXTERNAL_INFIX_PATH)/board/common/post-image.sh"
+BR2_ROOTFS_POST_SCRIPT_ARGS="$(BR2_DEFCONFIG)"
+
+# Linux headers same as kernel
+BR2_PACKAGE_HOST_LINUX_HEADERS_CUSTOM_5_15=y
+
+# Kernel
+BR2_LINUX_KERNEL=y
+BR2_LINUX_KERNEL_CUSTOM_VERSION=y
+BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="5.15.18"
+BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG=y
+BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE="board/qemu/x86_64/linux.config"
+BR2_LINUX_KERNEL_NEEDS_HOST_LIBELF=y
+
+# host-qemu for gitlab testing
+#BR2_PACKAGE_HOST_QEMU=y
+#BR2_PACKAGE_HOST_QEMU_SYSTEM_MODE=y
diff --git a/external.desc b/external.desc
new file mode 100644
index 00000000..af8d2e2d
--- /dev/null
+++ b/external.desc
@@ -0,0 +1,2 @@
+name: INFIX
+desc: Inf/IX by KernelKit
diff --git a/external.mk b/external.mk
new file mode 100644
index 00000000..e69de29b
diff --git a/patches/.empty b/patches/.empty
new file mode 100644
index 00000000..e69de29b