4 hour NetBSD kernel compile tutorial

1. NetBSD workshop
Jun Ebihara
jun@soum.co.jp
jun@netbsd.org

2. OverView in 4hours
● Install NetBSD/amd64 on VirtualBox
– Make earmv6hf cross-compiling toolchain
– Make RPI kernel
● Install NetBSD/earmv6hf on RPI
– Play RPI with NetBSD
– Feel difference between your favorite environment
● Copy your RPI kernel to RPI
– Update NetBSD-current kernel
● Boot RPI with your cross-compiled kernel

3. Hardwares
● Windows 10 PC with VirtualBox
● Raspberry PI
– MicroSD Card: Over 4GB class 10
– HDMI Display
– USB Keyboard/mouse
– USB power supply
– Ethernet Cable
● Internet access via Ethernet Cable
– RPI get IP address via DHCP
– RPI set time via NTP

4. Pre-Downloading
● NetBSD-7.1.amd64.iso
● src.tar.gz
● VirtualBox
● Rawrite32.exe
● RPI Image
– 2017-07-15-netbsd-earmv6hf.img.gz or newer
– http://cdn.netbsd.org/pub/NetBSD/misc/jun/raspberry-pi
– http://mail-index.netbsd.org/port-arm/2017/07/13/msg004307.html
– https://github.com/ebijun/NetBSD/blob/master/RPI/RPIimage/READ
ME

5. VirtualBox
● NetBSD on VirtualBox
– Assign 2GB mem: Disk 10GB
● NetBSD-7.1-amd64.iso
● Set NetBSD source on /usr/src
– cd /usr
– ftp
http://cdn.netbsd.org/pub/NetBSD/NetBSD-current/tar_files/src.tar
.gz
– tar xzvf src.tar.gz

6. NetBSD RPI Image
● on Windows
● http://cdn.netbsd.org/pub/NetBSD/misc/jun/raspberry-
pi/2017-07-15-earmv6hf/2017-07-15-netbsd-raspi-
earmv6hf.img.gz
● http://www.netbsd.org/~martin/rawrite32/download.html
● Use rawrite32 to write RPI image to microSD
● Connect RPI:
● Boot
● Wait 15 min to resize partition

7. Using RPI image
● Login: root
● startx
● medit
● mikutter
● mlterm-fb
● omxplayer & youtube-dl
– pkg_add omxplayer
– pkg_add youtube-dl

8. PaX
● Some application exec failed on starting
● sysctl -a |grep pax
– security.pax.mprotect.enabled = 1
– security.pax.mprotect.global = 1
– security.pax.mprotect.ptrace = 1
– security.pax.mprotect.debug = 1
– security.pax.segvguard.enabled = 1
– security.pax.segvguard.global = 1
● Loooose protection: (bad manner)
– sysctl -w security.pax.mprotect.enabled=0

9. NTP time setting
● ntpq -p
● /etc/rc.d/ntpd stop
● /etc/rc.d/ntpdate start
● /etc/rc.d/ntpd start
● ntpq -p

10. Reboot and / mount failed
● Power supply cut down failure
– make file system damaged
● Reboot but / read only access
● drop on single usermode
– df
– fsck /dev/ld0a
– reboot
● /etc/fstab
– add “log,noatime”
– man 5 fstab

11. RPI:/boot
● Kernel
– kernel.img – kernel for RPI0/1
– kernel7.img – kernel for RPI2/3
● cmdline.txt
– root=ld0a console=fb
– Add -s to boot single user mode
● config.txt
– http://elinux.org/RPiconfig
– hdmi_group=2
– hdmi_mode=16

12. /etc/rc.conf
● rc_configred=YES
● sshd=YES
● ntpd=YES
● hostname=nandemoii

13. NetBSD source
● dhcpcd
● ftp
http://cdn.netbsd.org/pub/NetBSD/NetBSD-current
/tar_files/src.tar.gz
● tar xzvf src.tar.gz
● mv src /usr/src
● mkdir /usr/obj

14. Kernel cross build for RPI2
● cd /usr/src
● ./build.sh -u -U -m evbarm -a earmv6hf tools
● ./build.sh -u -U -m evbarm -a earmv6hf
kernel=RPI2
● Copy netbsd.bin to /boot/kernel7.img
● objdump -D netbsd.bin
● Copy netbsd.bin to RPI:/boot/kernel7.img
● Set over 2GB mem for VirtualBox,if failed

15. Kernel cross build for KOBO
● cd /usr/src
● ./build.sh -j 6 -u -U -m evbarm -a earmv7hf
tools
● ./build.sh -j 6 -u -U -m evbarm -a earmv7hf
kernel=KOBO
● Copy netbsd.bin to /boot/kernel7.img
● objdump -D netbsd.bin

16. Kernel cross build for NetWalker
● cd /usr/src
● ./build.sh -j 6 -u -U -m evbarm -a earmv7hf
tools
● ./build.sh -j 6 -u -U -m evbarm -a earmv7hf
kernel=NETWALKER
● Copy netbsd.bin to /boot/kernel7.img
● objdump -D netbsd.bin

17. Kernel cross build for earmv4
● cd /usr/src
● ./build.sh -j 6 -u -U -m hpcarm tools
● ./build.sh -j 6 -u -U -m hpcarm kernel=WZERO3
● Copy netbsd to MSDOS partition
● Copy
/usr/src/sys/arch/hpc/stand/binary/ARM/hpcboot.exe.uue
● Uudecode hpcboot.exe.uue
● objdump -D netbsd

18. Kernel cross build for mipsel
● cd /usr/src
● ./build.sh -j 6 -u -U -m hpcmips tools
● ./build.sh -j 6 -u -U -m hpcmips kernel=GENERIC
● Copy netbsd to MSDOS partition
● Copy
/usr/src/sys/arch/hpc/stand/binary/MIPS/hpcboot.exe.uue
● Uudecode hpcboot.exe.uue
● objdump -D netbsd

19. Kernel cross build for sh3
● cd /usr/src
● ./build.sh -j 6 -u -U -m hpcsh tools
● ./build.sh -j 6 -u -U -m hpcsh kernel=GENERIC
● Copy netbsd to MSDOS partition
● Copy
/usr/src/sys/arch/hpc/stand/binary/SH3/hpcboot.exe.uue
● uudecode hpcboot.exe.uue
● objdump -D netbsd

20. Kernel cross build for sh4
● cd /usr/src
● ./build.sh -j 6 -u -U -m dreamcast tools
● ./build.sh -j 6 -u -U -m dreamcast
kernel=GENERIC
● objdump -D netbsd

21. Paths
● /etc/mk.conf
● /usr/src
– obj → ln -s /usr/obj
● tooldir.NetBSD-8.99.1-amd64
– bin/nbmake-hpcmips
● destdir.hpcmips
● releasedir
– sys/arch/hpcmips/
● conf/GENERIC
● compile/obj/GENERIC/netbsd
● compile/obj/GENERIC/netbsd.bin
● compile/obj/GENERIC/netbsd.ub

22. CVS update
● cd /usr/src
● script 20170810.log
● cvs update -Pad
● exit
● grep -v Updating 20170810.log |more

23. MediaTek MT7620
● ELECOM WRH-300CR
● http://pastebin.com/n05jnhjs
● NetBSD/evbmips:
● /usr/src/sys/arch/evbmips/conf
● grep MT7620
– ZYXELKX

24. Kernel cross build for MT7620
● cd /usr/src
● ./build.sh -j 6 -u -U -m evbmips -a mipsel tools
● ./build.sh -j 6 -u -U -m evbmips -a mipsel
kernel=ZYXELKX
● objdump -D netbsd

25. OrangePI
● Allwinnler H
● earmv7hf
● https://github.com/jaredmcneill/netbsd-arm-
docs/wiki/Allwinner

26. Kernel cross build for OrangePI
● cd /usr/src
● ./build.sh -j 6 -u -U -m evbarm -a earmv7hf
tools
● ./build.sh -j 6 -u -U -m evbarm -a earmv7hf
kernel=SUNXI
● https://github.com/jaredmcneill/netbsd-arm-
docs/wiki/Allwinner
● objdump -D netbsd.bin

27. Uboot
● Armbian
– https://github.com/ebijun/NetBSD/blob/master/sunxi/u-boot
/Makefile
– apt-get install binutils-arm-none-eabi
– apt-get install gcc-arm-none-eabi
– apt-get install swig libpython-dev
– make ${BOARD}_defconfig;make
● pkgsrc/sysutils/u-boot-orangepi-plus2e
● dd if=u-boot-sunxi-with-spl.bin of=imagefile bs=1024
seek=8 conv=sync

28. dmesg
● https://github.com/ebijun/NetBSD/tree/master/
dmesg
● http://dmesgd.nycbug.org/index.cgi