Difference between revisions of "PineNote Development/Flashing"

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Currently, the only ways to flash software using rkdeveloptool or from the factory Android installation (UART shell, adb, or fastboot).
{{Under construction}}
 
{{Info|These instructions are directed towards experienced developers only!}}
 
This page contains information on flashing software to the [[PineNote]].
The general process is as follows:
# Take a backup of all important data on the PineNote
# Modify the partition layout to make space for your desired Linux distribution
# Instantiate a root filesystem (rootfs) in the new partition space
# Install your Linux distribution to the boot partition
# Modify the boot process to boot the Linux distribution by default
 
There are multiple possible methods of executing these steps, and this page attempts to document all of them.
You can use:
# <code>rkdeveloptool</code>, a command line utility for modifying [https://en.wikipedia.org/wiki/Rockchip Rockchip] devices over USB
# The [[PineNote_Development/UART|UART]] shell
# [https://en.wikipedia.org/wiki/Android_Debug_Bridge Android Debug Bridge]
# [https://en.wikipedia.org/wiki/Fastboot Fastboot]
 
== Getting <code>rkdeveloptool</code> ==
 
Most flashing operations on the PineNote are done through <code>rkdeveloptool</code>, a command line utility built on libusb.
PINE64 maintains its own fork [https://gitlab.com/pine64-org/quartz-bsp/rkdeveloptool here] that you will need to get.
The repo's README contains a list of dependencies (libusb 1.0) and instructions for building the tool.
 
Installing (not just building) <code>rkdeveloptool</code> will configure PAM to elevate privileges where necessary on your system; you can configure this manually as follows:
<pre>
sudo cp 99-rk-rockusb.rules /etc/udev/rules.d/
sudo udevadm control --reload
</pre>
 
== Entering Maskrom/Rockusb mode ==
 
Interfacing with the PineNote over USB using <code>rkdeveloptool</code> requires first booting the PineNote into [http://opensource.rock-chips.com/wiki_Rockusb an alternative operating mode] called Maskrom or Rockusb mode.
 
=== Possible methods ===
 
There are three possible methods of entering Maskrom/Rockusb mode:
 
==== Hardware magnet switch ====
 
# Connect the PineNote to your computer via USB and boot the PineNote into Android
# Locate & identify the small circular marking on the back of the PineNote, in the top right quadrant; have the PineNote pen close at hand, or any other small magnet
# Hold the PineNote power button to bring up the reboot/shutdown menu; select reboot, then place the PineNote face down with the "eraser" end of the pen (or your magnet) resting on the small circular marking
 
<gallery>
Download mode.jpeg|Pen method
PineNoteMagnetOnBack.jpg|Magnet method
</gallery>
 
==== U-Boot terminal ====
This method requires a [[PineNote_Development/UART#USB_passthrough|UART dongle with passthrough]] allowing simultaneous UART & USB connections.
It is nice because you can easily switch back & forth between U-Boot and Rockusb without having to physically manipulate the PineNote or its connectors; this is especially helpful when trying to develop U-Boot.
 
# Connect to the PineNote via UART and USB simultaneously
# Interrupt the U-Boot startup using <code>ctrl+c</code> sent over UART
# In the U-Boot terminal over UART, run <code>rockusb 0 mmc 0</code>
 
The UART terminal should print <code>RKUSB</code> then a spinner will appear.
You can exit back to the U-Boot terminal by sending <code>ctrl+c</code> again.
 
==== Shorting test points ====
 
If the bootloader is broken/corrupted, you cannot get to Maskrom without opening up the device (it can be opened using spudger and a bit of patience).
 
Once inside, short TP1301 (GND) and TP1302 (eMMC_D0/FLASH_D0) with a small tweezers, this is how it looks on board view (credit to Caleb):
 
[[File:PineNote_Maskrom_TP.png|500px]]
 
=== Success ===
 
No matter what approach you take, you can tell whether you succeeded by running the <code>lsusb</code> command on your computer:
* If you find the entry <code>2207:0018 Fuzhou Rockchip Electronics Company rk3566_eink</code> in the list, the process did not succeed; reboot and retry
* The entry <code>2207:350a Fuzhou Rockchip Electronics Company</code> will occur if you detach then reattach the USB-C cable while the PineNote is in Maskrom/Rockusb mode; <code>rkdeveloptool</code> won't work and you will have to do a hard reboot (hold down power button for 30 seconds to shutdown)
* If you find the entry <code>2207:350a Fuzhou Rockchip Electronics Company USB download gadget</code> then the process succeeded
 
You can also look at the output of the <code>rkdeveloptool list</code> command:
* If this prints out <code>No devices in rockusb mode found</code> the process did not succeed; reboot and retry
* If this prints out <code>DevNo=1 Vid=0x2207,Pid=0x350a,LocationID=305 Maskrom</code> then you probably detached/reattached the USB-C cable while in Maskrom/Rockusb mode and <code>rkdeveloptool</code> won't work; perform a hard reboot to fix
* If this prints out <code>DevNo=1 Vid=0x2207,Pid=0x350a,LocationID=303 Loader</code> then the process succeeded
 
=== Exiting ===
 
You can boot the PineNote back into its normal mode of operation by powercycling the PineNote with its hardware power switch, or running the <code>rkdeveloptool reboot</code> command.
If you used the magnetic switch method be sure to remove the pen/magnet before rebooting.


== Backup ==
== Backup ==


{{Info|A backup of the content of the internal eMMC before anything gets messed is '''mandatory'''.}}
A backup of the content of the internal eMMC before anything gets messed up is '''mandatory'''.


Especially the ''waveform'' partition contains data '''unique''' to your PineNote and is a prime candidate for backup.
Especially the ''waveform'' partition contains data '''unique''' to your PineNote and is a prime candidate for backup.


But other partitions like U-Boot (need for any operation of the device) or the un-partitioned space at the beginning containing the GPT partition table (and presumably the VCOM setting for the e-ink display and maybe device mac addresses) contains data you may wish to backup.
Other partitions like U-Boot (need for any operation of the device) or the un-partitioned space at the beginning containing the GPT partition table (and presumably the VCOM setting for the e-ink display and maybe device mac addresses) contain data you may also wish to backup.


Depending of your personal level of data hoarder you may want to backup more than this or even just everything (the large ''userdata'' partition is supposed to be able to be repopulated as empty space by Android)
Depending of your personal level of data hoarder you may want to backup more than this or even just everything (the large ''userdata'' partition is supposed to be able to be repopulated as empty space by Android)
Line 13: Line 97:
In any case it is easier to restore/extract data from a backup than not having one if you need one.
In any case it is easier to restore/extract data from a backup than not having one if you need one.


=== Manually using rkdeveloptool ===
This process was developed by Dorian Rudolph, originally described [https://github.com/DorianRudolph/pinenotes here].
Dorian has some nice [https://github.com/DorianRudolph/pinenotes notes regarding the PineNote]
 
Don't forget to install a patched U-Boo for reading beyond 32MB and to respect the 2GB limit/bug of the current rkdeveloptool as per his notes
 
{{Under construction}}


Build rkdeveloptool:
=== List partitions ===


git clone https://gitlab.com/pine64-org/quartz-bsp/rkdeveloptool.git
First, run <code>rkdeveloptool list-partitions</code> to print out your PineNote's partitions to get an idea of what you're dealing with.
cd rkdeveloptool
The stock PineNote has a fairly standard [https://source.android.com/docs/core/architecture/partitions Android partition setup]:
mkdir build
cd build
cmake ..


Download mode
{| class="wikitable"
Enter the download mode by placing the pen as pictured below. A magnet placed where the pen's cap is should also work (haven't tried). I guess the dot on the case also indicates the position of the sensor.
|-
! Number !! Name !! Size !! Purpose
|-
| 0 || uboot || 4 MB || The [https://en.wikipedia.org/wiki/Das_U-Boot U-Boot] embedded systems bootloader
|-
| 1 || trust || 4 MB || Secrets that can be encrypted with a key stored in the [https://en.wikipedia.org/wiki/Trusted_Platform_Module TPM]
|-
| 2 || waveform || 2 MB || Important files controlling the e-ink screen's state changes
|-
| 3 || misc || 4 MB || Data used by the recovery partition
|-
| 4 || dtbo || 4 MB || [https://en.wikipedia.org/wiki/Devicetree Device Tree Blob for Overlay], files describing the PineNote's hardware configuration
|-
| 5 || vbmeta || 1 MB || Data required for [https://android.googlesource.com/platform/external/avb/+/master/README.md verified boot]
|-
| 6 || boot || 42 MB || The kernel image & ramdisk to boot
|-
| 7 || security || 4 MB ||
|-
| 8 || recovery || 134 MB || The recovery image, booted during Android updates
|-
| 9 || backup || 400 MB ||
|-
| 10 || cache || 1 GB || Stores temporary data; can be used to install a minimal Linux distribution!
|-
| 11 || metadata || 17 MB || Used for disk encryption
|-
| 12 || super || 3.25 GB || Android itself is installed here
|-
| 13 || logo || 17 MB || Splash image displayed during boot
|-
| 14 || device || 67 MB ||
|-
| 15 || userdata || 119 GB || The big one; user-installed Android apps and files live here
|}


placing pen on the back
=== Patch U-Boot ===


<code>lsusb</code> should now recognize the PineNote as:
Before we can back up our partitions, we have a problem to solve.
The version of U-Boot installed on the stock PineNote contains a bug where it can't dump partitions beyond 32 MB (above that limit all bytes in the dump are just <code>0xCC</code>), meaning the PineNote must be flashed with a fixed version of U-Boot before it is possible to take a backup of the larger partitions.
It is possible to extract and modify the U-Boot image from your PineNote if you're interested in some light reverse-engineering (following Dorian's notes), or you can simply download a patched U-Boot image directly [https://github.com/DorianRudolph/pinenotes/blob/main/static/uboot_patched.img here].


2207:350a Fuzhou Rockchip Electronics Company USB download gadget
Once you've acquired a patched U-Boot image, run:
# <code>rkdeveloptool read-partition uboot uboot_backup.img</code>
# <code>rkdeveloptool write-partition uboot uboot_patched.img</code>
# <code>rkdeveloptool reboot</code>


List partitions:
=== Taking the backup ===


> rkdeveloptool list-partitions                     
With U-Boot patched, you can back up every partition except for super and userdata; run:
#  LBA start (sectors)  LBA end (sectors)  Size (bytes)      Name               
00                16384              24575      4194304      uboot
01                24576              32767      4194304      trust
02                32768              36863      2097152      waveform
03                36864              45055      4194304      misc
04                45056              53247      4194304      dtbo
05                53248              55295      1048576      vbmeta
06                55296            137215      41943040      boot
07              137216            145407      4194304      security
08              145408            407551    134217728      recovery
09              407552            1193983    402653184      backup
10              1193984            3291135    1073741824      cache
11              3291136            3323903      16777216      metadata
12              3323904            9697279    3263168512      super
13              9697280            9730047      16777216      logo
14              9730048            9861119      67108864      device
15              9861120          241827775  118766927872      userdata


<code>rkdeveloptool read-partition partition_name partition_name_backup.img</code>


{{Warning|this process is very new! Proceed at your own risk.}}
Unfortunately the super and userdata partitions run into a second limitation preventing dumping partitions larger than 2 GB, this time originating in <code>rkdeveloptool</code> itself.
This means if you have a large number of documents in the Android userdata partition they might not all make it into the backup.
If you don't have many documents (or don't care about losing them) this should not be a problem.
If you do have a lot of documents, workarounds include:
* A possible patch written by Thomas exists [https://github.com/tpwrules/nixos-pinenote/blob/96d2c9158edb9da59afcb952cc864fada18382f9/nix/rkdeveloptool/0001-fix-large-dumps.patch here] but has not yet been upstreamed; consider investigating how to get the patch tested & upstreamed, or just apply it to your own local copy of <code>rkdeveloptool</code>
* Use [https://github.com/talpadk/pinenote-backup this] Python script written by Visti Andresen (talpadk) to automatically backup your entire partition by splitting reads into 2 GB chunks


See [https://github.com/m-weigand/pinenote-debian-recipes/releases/tag/v0.1 instructions on this artifact]. It will instruct you on extracting the rootfs into an empty ext4 partition. This can be done from Linux or Android. Further instructions on building your own rootfs [https://github.com/m-weigand/pinenote-debian-recipes can be found here].
See [https://github.com/m-weigand/pinenote-debian-recipes/releases/tag/v0.1 instructions on this artifact]. It will instruct you on extracting the rootfs into an empty ext4 partition. This can be done from Linux or Android. Further instructions on building your own rootfs [https://github.com/m-weigand/pinenote-debian-recipes can be found here].
=== Automated backup using a script and rkdeveloptool ===
[https://github.com/talpadk/pinenote-backup pinenote-backup] is a python script for detecting the partitions and automating the backup of partitions or the whole disk.
It also requires a patched u-boot but automatically handles the 2GB limit by splitting up larger reads into smaller ones
=== Using the factory Android installation ===
TODO


=== Using a user installed Linux ===
=== Using a user installed Linux ===
Line 101: Line 197:


== Using rkdeveloptool ==
== Using rkdeveloptool ==
rkdeveloptool is a command line utility built on libusb.
=== Downloading and Building rkdeveloptool ===
PINE64 develops [https://gitlab.com/pine64-org/quartz-bsp/rkdeveloptool its own updated fork of rkdeveloptool on GitLab].
You will need to have libusb 1.0, its development headers and scdoc installed.
<pre>
git clone https://gitlab.com/pine64-org/quartz-bsp/rkdeveloptool.git
cd rkdeveloptool
mkdir build
cd build
cmake ..
</pre>
This sets up all the build files. You can then compile with <code>make</code> inside the build directory.
After you're done, you'll likely also need to install the udev rules, or else your user won't have permission to access the USB devices:
<pre>
sudo cp 99-rk-rockusb.rules /etc/udev/rules.d/
sudo udevadm control --reload
</pre>
Copying the udev rules is also performed automatically when you <code>make install</code>.


=== Building Downstream U-Boot ===
=== Building Downstream U-Boot ===
Line 184: Line 253:
</blockquote>
</blockquote>


=== Entering Maskrom/Rockusb Mode ===
You can now download u-boot onto the PineNote:
 
There are three ways to get into Maskrom/Rockusb mode:
 
====  The easy way ====
 
# Flip the device around so that the display faces down
# Lay the pen on the right side, with its tip pointing towards the speaker grill, and its magnet pointing towards the upper right corner of the label on the back (or place the magnetic cap from the pen on the spot marked on the back).
# Turn the device on and wait for it to show up in <code>lsusb</code>. It should now be in Loader mode, according to <code>rkdeveloptool list-devices</code> (note that ''Loader'' here indicates U-Boot's Rockusb; separately, booting with an erased eMMC displays ''Maskrom'' (not ''Loader'') from the RK3566).
# Unplug the device and plug it back in. It should now be in Rockusb mode.
 
This can be a bit fiddly to get right and may need a few tries.
 
==== The u-boot way ====
# Interrupt the u-boot startup using ''ctrl-c'' (while attached using an UART dongle)
# While in u-boot use the command <code>rockusb 0 mmc 0</code> to start Rockusb mode.
 
One benefit from this is, that if you have an UART dongle that allows to simultaneous having an UART and USB connection, there is no need to plug and unplug cables and flipping the PineNote around and placing magnets. 
 
This is especially helpful when changing back and forth between U-Boot and Rockusb, for instance when trying to develop u-boot.
 
==== Shorting test points ====
 
If the bootloader is broken/corrupted, you cannot get to Maskrom without opening up the device (it can be opened using spudger and a bit of patience).
 
Once inside, short TP1301 (GND) and TP1302 (eMMC_D0/FLASH_D0) with a small tweezers, this is how it looks on board view (credit to Caleb):
 
[[File:PineNote_Maskrom_TP.png|500px]]
 
Then plug the device to the computer and if you see the device with VID=2207/PID=350a then it should be in Maskrom mode, you can verify by typing <code>rkdeveloptool list-devices</code>.
 
<nowiki>Jan 07 15:04:13 melttower kernel: usb 1-14: New USB device found, idVendor=2207, idProduct=350a, bcdDevice= 1.00
Jan 07 15:04:13 melttower kernel: usb 1-14: New USB device strings: Mfr=0, Product=0, SerialNumber=0
 
$ rkdeveloptool list-devices
DevNo=1 Vid=0x2207,Pid=0x350a,LocationID=10e    Maskrom</nowiki>
 
 
If nothing shows up, you can try to hold down the power button for 5 seconds and then try again.
 
=== Running rkdeveloptool ===
 
First, you'll want to make sure the device you've connected is in maskrom mode:
 
./rkdeveloptool list
 
It should output something like "''DevNo=1 Vid=0x2207,Pid=0x350a,LocationID=202 Maskrom''". If it doesn't, see [[PineNote Development#Entering Maskrom Mode]].
 
You can now download u-boot onto it:


  ./rkdeveloptool boot ../u-boot-rockchip/rk356x_spl_loader_v1.08.111.bin
  ./rkdeveloptool boot ../u-boot-rockchip/rk356x_spl_loader_v1.08.111.bin

Latest revision as of 15:21, 24 October 2023

This page or section is under construction

Please help to review and edit this page or section. Information are subject to change.

Note: These instructions are directed towards experienced developers only!

This page contains information on flashing software to the PineNote. The general process is as follows:

  1. Take a backup of all important data on the PineNote
  2. Modify the partition layout to make space for your desired Linux distribution
  3. Instantiate a root filesystem (rootfs) in the new partition space
  4. Install your Linux distribution to the boot partition
  5. Modify the boot process to boot the Linux distribution by default

There are multiple possible methods of executing these steps, and this page attempts to document all of them. You can use:

  1. rkdeveloptool, a command line utility for modifying Rockchip devices over USB
  2. The UART shell
  3. Android Debug Bridge
  4. Fastboot

Getting rkdeveloptool

Most flashing operations on the PineNote are done through rkdeveloptool, a command line utility built on libusb. PINE64 maintains its own fork here that you will need to get. The repo's README contains a list of dependencies (libusb 1.0) and instructions for building the tool.

Installing (not just building) rkdeveloptool will configure PAM to elevate privileges where necessary on your system; you can configure this manually as follows:

sudo cp 99-rk-rockusb.rules /etc/udev/rules.d/
sudo udevadm control --reload

Entering Maskrom/Rockusb mode

Interfacing with the PineNote over USB using rkdeveloptool requires first booting the PineNote into an alternative operating mode called Maskrom or Rockusb mode.

Possible methods

There are three possible methods of entering Maskrom/Rockusb mode:

Hardware magnet switch

  1. Connect the PineNote to your computer via USB and boot the PineNote into Android
  2. Locate & identify the small circular marking on the back of the PineNote, in the top right quadrant; have the PineNote pen close at hand, or any other small magnet
  3. Hold the PineNote power button to bring up the reboot/shutdown menu; select reboot, then place the PineNote face down with the "eraser" end of the pen (or your magnet) resting on the small circular marking

U-Boot terminal

This method requires a UART dongle with passthrough allowing simultaneous UART & USB connections. It is nice because you can easily switch back & forth between U-Boot and Rockusb without having to physically manipulate the PineNote or its connectors; this is especially helpful when trying to develop U-Boot.

  1. Connect to the PineNote via UART and USB simultaneously
  2. Interrupt the U-Boot startup using ctrl+c sent over UART
  3. In the U-Boot terminal over UART, run rockusb 0 mmc 0

The UART terminal should print RKUSB then a spinner will appear. You can exit back to the U-Boot terminal by sending ctrl+c again.

Shorting test points

If the bootloader is broken/corrupted, you cannot get to Maskrom without opening up the device (it can be opened using spudger and a bit of patience).

Once inside, short TP1301 (GND) and TP1302 (eMMC_D0/FLASH_D0) with a small tweezers, this is how it looks on board view (credit to Caleb):

PineNote Maskrom TP.png

Success

No matter what approach you take, you can tell whether you succeeded by running the lsusb command on your computer:

  • If you find the entry 2207:0018 Fuzhou Rockchip Electronics Company rk3566_eink in the list, the process did not succeed; reboot and retry
  • The entry 2207:350a Fuzhou Rockchip Electronics Company will occur if you detach then reattach the USB-C cable while the PineNote is in Maskrom/Rockusb mode; rkdeveloptool won't work and you will have to do a hard reboot (hold down power button for 30 seconds to shutdown)
  • If you find the entry 2207:350a Fuzhou Rockchip Electronics Company USB download gadget then the process succeeded

You can also look at the output of the rkdeveloptool list command:

  • If this prints out No devices in rockusb mode found the process did not succeed; reboot and retry
  • If this prints out DevNo=1 Vid=0x2207,Pid=0x350a,LocationID=305 Maskrom then you probably detached/reattached the USB-C cable while in Maskrom/Rockusb mode and rkdeveloptool won't work; perform a hard reboot to fix
  • If this prints out DevNo=1 Vid=0x2207,Pid=0x350a,LocationID=303 Loader then the process succeeded

Exiting

You can boot the PineNote back into its normal mode of operation by powercycling the PineNote with its hardware power switch, or running the rkdeveloptool reboot command. If you used the magnetic switch method be sure to remove the pen/magnet before rebooting.

Backup

A backup of the content of the internal eMMC before anything gets messed up is mandatory.

Especially the waveform partition contains data unique to your PineNote and is a prime candidate for backup.

Other partitions like U-Boot (need for any operation of the device) or the un-partitioned space at the beginning containing the GPT partition table (and presumably the VCOM setting for the e-ink display and maybe device mac addresses) contain data you may also wish to backup.

Depending of your personal level of data hoarder you may want to backup more than this or even just everything (the large userdata partition is supposed to be able to be repopulated as empty space by Android)

In any case it is easier to restore/extract data from a backup than not having one if you need one.

This process was developed by Dorian Rudolph, originally described here.

List partitions

First, run rkdeveloptool list-partitions to print out your PineNote's partitions to get an idea of what you're dealing with. The stock PineNote has a fairly standard Android partition setup:

Number Name Size Purpose
0 uboot 4 MB The U-Boot embedded systems bootloader
1 trust 4 MB Secrets that can be encrypted with a key stored in the TPM
2 waveform 2 MB Important files controlling the e-ink screen's state changes
3 misc 4 MB Data used by the recovery partition
4 dtbo 4 MB Device Tree Blob for Overlay, files describing the PineNote's hardware configuration
5 vbmeta 1 MB Data required for verified boot
6 boot 42 MB The kernel image & ramdisk to boot
7 security 4 MB
8 recovery 134 MB The recovery image, booted during Android updates
9 backup 400 MB
10 cache 1 GB Stores temporary data; can be used to install a minimal Linux distribution!
11 metadata 17 MB Used for disk encryption
12 super 3.25 GB Android itself is installed here
13 logo 17 MB Splash image displayed during boot
14 device 67 MB
15 userdata 119 GB The big one; user-installed Android apps and files live here

Patch U-Boot

Before we can back up our partitions, we have a problem to solve. The version of U-Boot installed on the stock PineNote contains a bug where it can't dump partitions beyond 32 MB (above that limit all bytes in the dump are just 0xCC), meaning the PineNote must be flashed with a fixed version of U-Boot before it is possible to take a backup of the larger partitions. It is possible to extract and modify the U-Boot image from your PineNote if you're interested in some light reverse-engineering (following Dorian's notes), or you can simply download a patched U-Boot image directly here.

Once you've acquired a patched U-Boot image, run:

  1. rkdeveloptool read-partition uboot uboot_backup.img
  2. rkdeveloptool write-partition uboot uboot_patched.img
  3. rkdeveloptool reboot

Taking the backup

With U-Boot patched, you can back up every partition except for super and userdata; run:

rkdeveloptool read-partition partition_name partition_name_backup.img

Unfortunately the super and userdata partitions run into a second limitation preventing dumping partitions larger than 2 GB, this time originating in rkdeveloptool itself. This means if you have a large number of documents in the Android userdata partition they might not all make it into the backup. If you don't have many documents (or don't care about losing them) this should not be a problem. If you do have a lot of documents, workarounds include:

  • A possible patch written by Thomas exists here but has not yet been upstreamed; consider investigating how to get the patch tested & upstreamed, or just apply it to your own local copy of rkdeveloptool
  • Use this Python script written by Visti Andresen (talpadk) to automatically backup your entire partition by splitting reads into 2 GB chunks

See instructions on this artifact. It will instruct you on extracting the rootfs into an empty ext4 partition. This can be done from Linux or Android. Further instructions on building your own rootfs can be found here.

Using a user installed Linux

A Linux installed to the cache partition should be able to easily backup everything over WiFi or to a USB stick/disk using dd.

However the user would need to backup the cache partition themself (if they want that).

And more importantly they would only be getting the backup after they started playing with the content of the eMMC.

Side-by-side setup

It is possible to set up a partition for mainline development without disturbing the factory Android installation. This allows updating a mainline kernel, DTB, and initramfs over Wi-Fi until WiFi or USB OTG is working in mainline Linux.

Without Repartitioning

The recommended partition for this is mmcblk0p11 aka /cache. It is large and already formatted as ext4, so it is readable from U-Boot. Here are some general steps:

  1. From the UART or adb shell, set up your chroot in /cache. I used the Alpine Linux rootfs tarball.
  2. Copy in your kernel and DTB, using for example scp or wget inside the chroot.
  3. Finally, create and boot an extlinux.conf as described below.

With Repartitioning

It is possible to shrink the userdata partition, and create a new partition at the end for use with mainline Linux. This provides much more space than cache. However, because userdata is formatted with f2fs, and that filesystem cannot be shrunk, resizing the partition requires wiping userdata.

  1. Back up any necessary files from userdata
  2. Boot to a mainline kernel from mmcblk0p11, either using that partition as rootfs (see above), or using an initramfs with repartitioning tools
  3. Modify the partition table with your favorite tool, e.g. fdisk, gdisk, or parted
  4. Reboot into fastboot and wipe userdata.
  5. Reboot into Android, where you can now chroot in and install your favorite distribution to the new partition.

Using rkdeveloptool

Building Downstream U-Boot

While in maskrom mode, we need to have a u-boot to download onto the device for any of the other commands to work. To build you'll also need to install device-tree-compiler.

You also need to install Python and pyelftools.

Note that rkbin is a >5GB download! This will take some time to clone and process the deltas.

git clone -b quartz64 https://gitlab.com/pgwipeout/u-boot-rockchip.git
git clone -b rkbin https://github.com/JeffyCN/rockchip_mirrors.git rkbin
cd u-boot-rockchip
# If using Arch Linux, export CROSS_COMPILE=aarch64-linux-gnu-
export CROSS_COMPILE=aarch64-none-linux-gnu-
make rk3566-quartz64_defconfig
./make.sh

In the current version (current as of 2022-01-02), there might have to be made a change to one line to get a clean compilation:

diff --git a/lib/avb/libavb/avb_slot_verify.c b/lib/avb/libavb/avb_slot_verify.c
index 123701fc3b..64a1ce6450 100644
--- a/lib/avb/libavb/avb_slot_verify.c
+++ b/lib/avb/libavb/avb_slot_verify.c
@@ -296,7 +296,7 @@ static AvbSlotVerifyResult load_and_verify_hash_partition(
   bool image_preloaded = false;
   uint8_t* digest;
   size_t digest_len;
-  const char* found;
+  const char* found = NULL;
   uint64_t image_size;
   size_t expected_digest_len = 0;
   uint8_t expected_digest_buf[AVB_SHA512_DIGEST_SIZE];

For systems where the global python executable points to python2, compilation fails with an error related to pyelftools not being installed (even if it is). To fix this:

diff --git a/make.sh b/make.sh
index 2bba05b4e4..cfe5b0afd5 100755
--- a/make.sh
+++ b/make.sh
@@ -758,7 +758,7 @@ function pack_fit_image()
        fi
 
        if [ "${ARM64_TRUSTZONE}" == "y" ]; then
-               if ! python -c "import elftools" ; then
+               if ! python3 -c "import elftools" ; then
                        echo "ERROR: No python 'pyelftools', please: pip install pyelftools"
                        exit 1
                fi

You can now download u-boot onto the PineNote:

./rkdeveloptool boot ../u-boot-rockchip/rk356x_spl_loader_v1.08.111.bin

This should output "Downloading bootloader succeeded".

We can now verify that this worked using e.g. the "read flash info" command:

./rkdeveloptool read-flash-info
TODO: Section needs to be finished

Creating a mainline boot image

You can create a filesystem image that replaces the Android boot or recovery partition by doing roughly the following:

  1. Erase boot and dtbo with rkdeveloptool or fastboot (back them up first!!!)
  2. Create an ext2 partition image and mount it (fallocate, mkfs.ext2)
  3. Build your mainline kernel
  4. Copy the kernel, dtb and an initramfs to the root of the mounted image (use any old postmarketOS initramfs)
  5. Create a file in the root of the mounted image called extlinux.conf as described below
  6. Unmount the image and then use rkdeveloptool to flash it to the "recovery" partition on the pinenote (it's about the right size until we get around to replacing the partition layout).

Using fastboot

Follow the steps for Creating a mainline boot image, but instead of flashing it with rkdeveloptool, use fastboot. You can enter fastboot in either of two ways:

  • Use "reboot bootloader" from adb or a UART console or
  • get a U-Boot prompt and run fastboot usb 0.