PinePhone and PineTab kernel#

This document describes how to build and install the PinePhone or PineTab kernel. First the recovery system is explained. Then the actual building and installation. At the bottom there are some references.


The Ubuntu Touch image contains a recovery boot mode based on “jumpdrive”. To get into the recovery press and hold the power and volume-up buttons until the led turns on.

The recovery presents the PinePhone as a network device over USB and runs a telnet server. When you connect the PinePhone to your desktop via USB, you will see the rndis device show up in your desktop’s dmesg:

usb 1-7.2: Product: PinePhone
usb 1-7.2: Manufacturer: Pine64
usb 1-7.2: SerialNumber: Jumpdrive
rndis_host 1-7.2:1.0 usb0: register 'rndis_host' at usb-0000:00:14.0-7.2, RNDIS device

You can log in to the recovery system with telnet

The recovery also exposes the eMMC and the microSD card over USB. Assuming you have already installed Ubuntu Touch on your microSD card you will see something like this in your desktop’s dmesg:

usb-storage 1-7.2:1.2: USB Mass Storage device detected
scsi host3: usb-storage 1-7.2:1.2
scsi 2:0:0:0: Direct-Access     JumpDriv e eMMC                PQ: 0 ANSI: 2
scsi 2:0:0:1: Direct-Access     JumpDriv e microSD             PQ: 0 ANSI: 2
sd 2:0:0:0: Attached scsi generic sg1 type 0
scsi 2:0:0:1: Attached scsi generic sg2 type 0
sd 2:0:0:0: [sdb] 30785536 512-byte logical blocks: (15.8 GB/14.7 GiB)
sd 2:0:0:1: [sdc] 124735488 512-byte logical blocks: (63.9 GB/59.5 GiB)
  sdb: sdb1 sdb2
sd 2:0:0:0: [sdb] Attached SCSI removable disk
  sdc: sdc1 sdc2 sdc3 sdc4 sdc5 sdc6 sdc7 sdc8 sdc9 sdc10

The eMMC with jumpdrive contains two partitions: pmOS_boot and pmOS_root.

The microSD card with Ubuntu Touch contains 10 partitions: loader, scr, persist, boot_a, boot_b, recovery_a, recovery_b, cache, system and userdata. To update the kernel you want to mount boot_a. Check which device is the SDcard in your OS and mount boot_a. In the example above this is sdc4. Inside that partition you’ll see the kernel vmlinuz and related files: config-5.6.0-pine64 dtb initrd.img modules/ vmlinuz.

Building the kernel#

To install dependencies, get the source code, configure and build the kernel, run the following:

sudo apt install build-essential flex bison gcc-aarch64-linux-gnu libssl-dev
git clone -b pine64-kernel-ubports
cd linux
ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- KBUILD_VERSION=arm64 LOCALVERSION=-pine64 make pine64_defconfig
ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- KBUILD_VERSION=arm64 LOCALVERSION=-pine64 make -j18 bindeb-pkg

Install the kernel#

Boot into recovery and mount boot_a. Make a backup if needed. Then copy over your newly built kernel and if needed modules:

cp -v linux/debian/linux-image/boot/vmlinuz-5.6.0-pine64 [MOUNT POINT BOOT_A]/vmlinuz
cp -v linux/debian/linux-image/boot/config-5.6.0-pine64 [MOUNT POINT BOOT_A]
cp -v linux/debian/linux-image/boot/  [MOUNT POINT BOOT_A]
sudo rm -rf [MOUNT POINT BOOT_A]/modules
sudo cp -rv linux/debian/linux-image/lib/modules [MOUNT POINT BOOT_A]

Afterwards be sure to unmount the partition so it is cleanly written. Now you can reboot the PinePhone. Once booted, you can verify that the kernel has been successfully updated by checking the build date with uname -a on the device.