Building a bootable ARM SD

A few weeks ago, I wrote up how to make a bootable i386 image. People have been asking me to extend it for my ARM platform.

Here are the instructions for a hypothetical box that has a boot loader that can load an image from a FAT partition of a SD card, and FreeBSD runs off of a ufs partition on the SD card. This will be for a big endian ARM target, based on the AVILA kernel. I'm also assuming that this platform doesn't use FreeBSD's normal /boot/loader.

1. setenv MAKEOBJDIRPREFIX /blah
2. setenv TARGET arm
   
3. setenv TARGET_ARCH arm
4. setenv TARGET_CPU xscale
   
5. make buildworld
6. make buildkernel KERNCONF=AVILA
   
7. fdisk -I da0
8. fdisk -f disk-partitions da1
   
9. newfs -t msdos /dev/da0s1
   
10. bsdlabel -w da0s2 auto
11. newfs /dev/da0s2a
12. mount /dev/da0s2a /mnt
13. make installworld DESTDIR=/mnt
14. make installkernel DESTDIR=/mnt KERNCONF=AVILA INSTALL_NODEBUG=t
    
15. make distrib-dirs DESTDIR=/mnt
16. make distribution DESTDIR=/mnt
17. echo /dev/da0s2a / ufs rw 1 1 > /mnt/etc/fstab
18. echo ifconfig_DEFAULT=DHCP > /mnt/etc/rc.conf
19. echo hostname=demo >> /mnt/etc/rc.conf
20. cp /mnt/boot/kernel/kernel /tmp
    
21. umount /mnt
22. mount -t msdos /dev/da0s1 /mnt
23. cp /tmp/kernel /mnt
24. umount /mnt
    

In step 8, one needs to have a special file. Here's what I use, but one needs to automate it a little more. Here's a hand-tuned one that I used for a 1GB SD card I had laying around.

# partition table
g c940 h32 s63
p 1 6 63 201537
p 2 165 201600 1780128

Clearly, one needs to tune the above for their specific part. NanoBSD tries to automate this process, but that is beyond the scope of this posting.

Update: fixed step 17.