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title: Linux Bringup: NVME

USB drive boot

The easy way

  • As per Glanzmann's notes fetch a debian bullseye rootfs under MacOS and dd it directly into a newly created nvme partition.

The harder way

  • This is done on another Linux machine - uses debian bullseye

Build your rootfs

  • build your own 
    mkdir debinst
sudo debootstrap --arch arm64 --foreign bullseye debinst http://ftp.au.debian.org/debian/
sudo cp /usr/bin/qemu-aarch64-static debinst/usr/bin
    • Login via a chroot to a bash prompt:sudo LANG=C.UTF-8 chroot debinst qemu-aarch64-static /bin/bash
    • Then complete the 2nd stage /debootstrap/debootstrap --second-stage
    • While your there install any other packages you want: apt install file screenfetch procps
    • For ssh install an ssh server apt install openssh-server
    • Allow root login via ssh by setting PermitRootLogin yes via vi /etc/ssh/sshd_config
    • Most important set the root password passwd

Install rootfs onto USB drive

* Plug in your USB drive and create a partition with fdisk (assumes drive is /dev/sdb) `sudo fdisk /dev/sdb`
* Format partition (assumes it's the first one) `sudo mkfs.ext4 /dev/sdb1`
* Mount the drive some where like /mnt/img `sudo mount /dev/sdb1 /mnt/img`
* Install the rootfs you created above onto the drive `sudo cp -a debinst/. /mnt/img`
* Unmount the drive `sudo umount /mnt/img`

Boot with USB drive as root

* Back to [booting over USB cable](linux-bringup.md#running-linux-via-usb-cable)
* Make sure you have the latest m1n1.macho loaded `python3 proxyclient/tools/chainload.py build/m1n1.macho`
* Build a kernel with builtin features (check for =m and change to =y in .config)
* In particular need CONFIG_EXT4_FS=y is needed to boot!
* Try this [Asahi linux snapshot](https://github.com/amworsley/AsahiLinux/tree/asahi-kbd) and this [config](https://raw.githubusercontent.com/amworsley/asahi-wiki/main/images/config-keyboard+nvme)
* Then boot the gzipp'ed image with the USB drive. I had to plug the drive in the 2nd USB type-C port on the MBA (MacBook Air) through a Type-C to USB-Type A HUB.
* Be-aware when I plugged in a lower speed USB device (keyboard) it reset the HUB and corrupted my USB drive. So don't use a keyboard, a Type-A to Type-C dongle worked fine
* Over the USB cable load the new kernel and boot with the USB drive as the root filesystem:

python3 proxyclient/tools/linux.py -b 'earlycon console=tty0 console=tty0 debug net.ifnames=0 rw root=/dev/sda1 rootdelay=5 rootfstype=ext4' Image.gz t8103-j313.dtb * The root filesystem is in first partition of the drive (/dev/sda1) and it's a MBA (t8103-j313.dtb) * If your booting something different check the .dts file in arch/arm64/boot/dts/apple/ by looking at the value of the model field

Install rootfs in the nvme

  • Under MacOS you need to create some free space as per Glanzmann's notes
  • Be very careful you know exactly what partition you specify this is just an example your numbers may vary
  • make space - the last number is the space that macos will occupy diskutil apfs resizeContainer disk0s2 200GB
  • List the partitions and see where the free space now lies diskutil list
  • Allocate a FAT32 partition for your linux rootfs on the NVME from the free space
  • NOTE you have to specify the partition before the free space diskutil addPartition disk0s3 FAT32 LB 42.6GB
  • Boot with the USB ext4 USB drive as root (as above)
  • Use fdisk to confirm which partition is the new FAT32 one (it should have the size you created above too) fdisk -l /dev/nvme0n1
  • Once you have confirmed it format it to ext4 mkfs.ext4 /dev/nvme0n1p4
  • Mount it mount /dev/nvme0n1p4 /mnt
  • Copy your USB drive rootfs into it as before cp -ax /. /mnt
  • I believe the -x should prevent the recursive descent into the new filesystem on the nvme
  • Unmount it umount /mnt
  • Then try booting via the USB cable with your new root filesystem on the nvme ``` python3 proxyclient/tools/linux.py -b 'earlycon console=tty0 console=tty0 debug net.ifnames=0 rw root=/dev/nvme0n1p6 rootfstype=ext4' Image.gz t8103-j313.dtb