The scripts in this repository provide an easy way to set up Xen on raspberry pi 4 with:

• U-Boot as the bootloader,
• Xen as the hypervisor,
• Rpi Linux as dom0.

References

• Xen Wiki
• imagebuilder
• Xen on Raspberry Pi 4 Adventures
• TFTP -Community Help Wiki

Prerequisite

$ sudo apt install vim git bc bison u-boot-tools gcc-aarch64-linux-gnu \
flex libssl-dev make libncurses5-dev -y

0. TFTP server 세팅& Imagebuilder 다운로드

• TFTP server 세팅

$ sudo apt install tftpd-hpa
$ sudo mkdir /tftpboot
$ sudo vi /etc/default/tftpd-hpa

• tftpd-hpa Configuration File 수정

  TFTP_DIRECTORY="/tftpboot"
  TFTP_OPTIONS="--secure --create"
  

$ sudo chown -R tftp /tftpboot
$ sudo service tftpd-hpa restart

---

• Imagebuilder

$ git clone https://gitlab.com/viryaOS/imagebuilder.git/
$ cd imagebuilder
$ mkdir rpi

1. 라즈베리 파이 OS sd카드 마운트

$ mkdir /mnt/boot /mnt/rootfs
$ lsblk # usb 연결 확인
$ sudo mount /dev/sdX1 /mnt/boot
$ sudo mount /dev/sdX2 /mnt/rootfs
$ sudo vi /mnt/boot/config.txt

• config.txt에 다음 문장 추가

kernel=u-boot.bin
enable_uart=1
arm_64bit=1

2. boot.scr 파일 생성

$ sudo vi boot.source

• 다음 문장 추가

setenv serverip 192.168.0.xxx  // TFTP 서버의 IP주소

setenv ipaddr 192.168.0.xxx    // 라즈베리 파이 IP 주소

tftpb 0xC00000 boot2.scr

source 0xC00000

• boot.scr 생성

$ mkimage -T script -A arm64 -C none -a 0x2400000 -e 0x2400000 -d boot.source boot.scr
$ sudo cp boot.scr /mnt/boot/

3. U-boot.bin 파일 생성

$ git clone git://git.denx.de/u-boot.git
$ cd u-boot
$ export ARCH=arm64
$ export CROSS_COMPILE=aarch64-linux-gnu-
$ make rpi_4_defconfig
$ make all
$ sudo cp u-boot.bin /mnt/boot/

4. Xen 파일 생성

※ Xen 버전과 Buildroot로 생성하는 Xen 패키지 버전 일치해야함

※ Xen 버전은 4.14.2 이상 필수

$ git clone -b RELEASE-4.14.3 git://xenbits.xen.org/xen.git
$ cd xen
$ make -C xen XEN_TARGET_ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- defconfig
$ make -C xen XEN_TARGET_ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- menuconfig

• Xen config 세팅

  Debugging Options - - - >

  [ * ] Early printk (Early printk via 8250 UART) - - - >

  (0xfe215040) Early printk, physical base address of debug UART

  (2) Early printk, left-shift to apply to the register offsets within the 8250 UART

$ make dist-xen XEN_TARGET_ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- -j4
$ sudo cp xen/xen ~/imagebuilder/rpi/

5. 리눅스 이미지 파일 생성

$ gie clone -b rpi-5.10.y https://github.com/raspberrypi/linux
$ cd linux
$ KERNEL=kernel8
$ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- bcm2711_defconfig xen.config
$ sudo vi .config

• 리눅스 config 파일 수정

  CONFIG_XEN_BLKDEV_FRONTEND=y

  CONFIG_XEN_BLKDEV_BACKEND=y

  CONFIG_XEN_DEV_EVTCHN=y

  CONFIG_XENFS=y

  CONFIG_XEN_GNTDEV=y

  CONFIG_XEN_GRANT_DEV_ALLOC=y

$ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- Image dtbs modules 
$ sudo cp arch/arm64/boot/Image ~/imagebuilder/rpi
$ sudo cp arch/arm64/boot/dts/broadcom/bcm2711-rpi-4-b.dtb ~/imagebuilder/rpi

6. rootfs.cpio 파일 생성

$ git clone https://git.buildroot.net/buildroot
$ cd buildroot
$ make raspberrypi4_64_defconfig
$ make menuconfig

• buildroot 세팅
  • Toolchain
    • C library -> glibc
    • Kernel Headers -> Linux 5.10.x kernel headers
    • GCC compiler Version -> gcc 10.x
  • System configuration
    • Init system -> systemd
    • /bin/sh -> bash
  • Kernel
    • Kerenl version -> Custom Git repository
    • URL of custom repository -> https://github.com/raspberrypi/linux
    • Custom repository version -> rpi-5.10.y
  • Target packages
    • System tools

      -*- util-linux - - - >
      [ * ] basic set
      [ * ] xen
      [ ] Xen hypervisor
      [ * ] Xen tools

  • Filesystem Images
    • [ * ] cpio the root filesystem
    • [ * ] ext2/3/4 root filesystem

      ext2/3/4 variant (ext4)

    • (rootfs) filesystem label
    • (200M) exact size

$ make -j4
. . .
$ cd ~/linux
$ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- \
	INSTALL_MOD_PATH=/home/name/buildroot/output/target \
	modules_install
$ cd ~/buildroot
$ sudo rm -rf output/target/lib/modules/5.10.x-v8
$ make -j4
$ sudo cp output/images/rootfs.cpio.gz ~/imagebuilder/rpi

7. boot2.scr 생성

$ cd imagebuilder
$ sudo vi config

• config 파일 수정

  DEVICE_TREE="rpi/bcm2711-rpi-4-b.dtb"
  XEN="rpi/xen"
  XEN_CMD="console=dtuart dtuart=serial0 sync_console dom0_mem=1G dom0_max_vcpus=2”
  DOM0_KERNEL="rpi/Image"
  DOM0_RAMDISK="rpi/rootfs.cpio"
  NUM_DOMUS=0
  

$ ./scripts/uboot-script-gen -c config -d . -t tftp -o boot2
$ sudo cp boot2.scr /tftpboot
$ sudo cp -r rpi /tftpboot/

8. 부팅 후 Xen 초기 테스트

# xl list
# xl info
# ls -l /dev/xen
# xenstore-ls
# dmesg | grep Xen
# xl dmesg