VoLTE Implementation For Google Pixel 3a/3a XL

Eric H

@atarilinux
AFAIK, these devices use a super partition, but not a retro-fitted one.
But, I don't think the build system is aware of the partition type.

atarilinux

@Eric-H

Unfortunately, the Google Pixel 3a uses a retro-fitted partition for Android 12.1 and not the common super partition used in newer Android devices. According to the QA call:

Issues with building/installing:
*Issue with getting image on phone
*Has retrofitted system super-partition, this means two partitions act as they are one
*Has not been installed in this type of environment, we would need to figure it out

Also, the build was not completed.

It very well possible that this was figured out with these other device ports. However, these issues would need to be worked out with this Google Pixel 3a build as I understand it. I'm assuming that is why this build is not considered complete.

Eric H

@atarilinux

You have a retro-fitted super partition
You have images
You have the procedure to flash images in retro-fitted super partition : https://source.android.com/docs/core/architecture/bootloader/fastbootd#dynamic-partitions

What else ?

mr_growl

I flashed lineage 19.1-20231014-nightly-bonito-signed (which the wiki said should have android 12.1):

Android Version: 12 (according to the running system on the phone)
Lineage OS Version: 19-20231014-NIGHTLY-bonito
Phone Version: bonito
Phone Carrier: Amaysim (Optus)
Country: Australia

VoLTE is working just fine.

atarilinux

@Eric-H

What you have stated above is correct to the best of my knowledge. Here is the other part from the QA call:

*Source Material - Not Image
*Information on image build process, but not how to install it
*Built on top of latest Android 12.1 version for the Google Pixel 3a, but build not completed

So....it looks like we need to:

Finish the build (This part is the least specific. Finish what? This is the main issue due to it not being specific. Maybe it is only the retro-fitted partition issue? A lot of data may need to be checked to see what is complete. Here is the bottleneck in completing development.)
Build the image from source
Install image on the Google Pixel 3a

What we have currently:

Information on the retro-fitted partition and possible install process
Confirmation on VoLTE access for the Google Pixel 3a from other alternative OS's and carriers (It is possible!)
Specifically what to look for to see if the carrier supports your Google Pixel 3a (VoLTE Roaming is supported, Hardware check from carrier)

atarilinux

@mr_growl

Great news! Thanks for sharing! I think we are closer. Please see my last post to @Eric-H to see where we are now and the remaining items we will need to figure out.

ElliotLurie

@atarilinux

It seems like some data is lost from the deviceinfo file during the build process... Here's the output of unpack_bootimg after the build:

kernel_size: 18686554
ramdisk size: 6267912
os version: 12.0.0
os patch level: 2022-09
boot image header version: 3
command line args:

FPSensor

when the retrofitted partitions were implemented by pixel 3a stock rom? someone knows that? also would be nice to see if there are more devices that have retrofit to see how they merged it in the build system or what they adapted to get it working, i don remember what loop0 is to be honest

atarilinux

@ElliotLurie

Thanks! I'll see what I can find out on that. I'm new to this, so it may take me a while. However, looking at the older port and some other ports, I may be able to piece something together.

atarilinux

@FPSensor

Agreed. I do see some retro-fitted partiton ports with other alternative OS's. There could be one with Ubuntu Touch too, but I'm not fully aware of one at the moment. Mainly I see Super Partition ports or older Android 9 based ports. There is some documentation that we currently have available for retro-fitted partitions. Any knowledge on this can be shared across the Ubuntu Touch community.

Right now, it looks like we need to figure out what is going on with the deviceinfo file.

atarilinux

I got some information on the deviceinfo file, the Fastbootd process, and Retrofit partitions. Now I need to piece everything together, look at the code in the port, and see why some data is lost in the DeviceInfo file after the build process.

Android API for DeviceInfo
https://developer.android.com/reference/androidx/media3/common/DeviceInfo.Builder

DeviceInfo file reference from PostMarket OS
https://wiki.postmarketos.org/wiki/Deviceinfo_reference

DeviceInfo Flash Methods
https://wiki.postmarketos.org/wiki/Deviceinfo_flash_methods

Using Fastbootd and Retrofit Partitions
https://wiki.postmarketos.org/wiki/Android_dynamic_partitions

Eric H

@atarilinux
The UT deviceinfo file for the new port of sargo/bonito can be found here : https://gitlab.com/ubports/porting/community-ports/android12/google-pixel-3a/google-sargo/-/blob/main/deviceinfo?ref_type=heads

deviceinfo_kernel_cmdline is empty and should probably be completed.

The documentation is available at https://docs.ubports.com/en/latest/porting/build_and_boot/standalone_kernel_build.html#filling-in-your-deviceinfo

There is also a sample file : https://gitlab.com/ubports/porting/community-ports/halium-generic-adaptation-build-tools/-/blob/main/deviceinfo.sample?ref_type=heads

atarilinux

@Eric-H

Thanks! I'll take a look at this!

AetheralMeowstic

Well, since all US carriers require VoLTE and Android's about to implode in 2027, we kinda need to get at lease one device with Ubuntu Touch to support VoLTE.

AetheralMeowstic

@Eric-H But does the Halium 12 port have VoLTE?

arubislander

@AetheralMeowstic There are several devices that support VoLTE. However the Pixel 3a / XL is not (yet?) among those.

Eric H

@AetheralMeowstic
in the new halium 12 port for sargo and bonito, VoLTE is configured, yes, but the port is not finalized.

atarilinux

@mr_growl

Do you still have Lineage OS on your phone? We are looking at completing the device info file for this port. The kernel cmdline part is missing. Please see below from the KB Knowledge base. I'm thinking we can pull this info from Lineage OS and use it here if I am understanding correctly.

The kernel cmdline is one of the key things that is required to make the kernel boot. It has special parameters that allow the kernel to determine which features/things need to be enabled, and which need to be disabled. The Ubuntu Touch rootfs also relies on some key cmdlines which is required to boot, most specifically “console=tty0”. To adapt this to your device, try unpacking your boot image (section 8.3) and copying the cmdline from there, or take the help of a LineageOS device tree if it is available. “console=tty0” is a must for cmdline and should not be removed no matter what. Rest of the things can be removed and you can adjust these to your device. console=tty0 is a requirement for the rootfs to properly boot. systempart is added if you want to boot your rootfs from your system partition. It is supposed to point to your system partition.
deviceinfo_kernel_cmdline="console=tty0 bootopt=64S3,32N2,64N2 systempart=/dev/mapper/system"

atarilinux

@AetheralMeowstic

We have confirmed VoLTE is possible with Ubuntu Touch for the Google Pixel 3a. The VoLTE patch is included in this port. We just need to finish this port to get everything up an running. Currently, we need to get the device info file built.

The Ubuntu Touch community does see the need to get VoLTE up and running for those in the US and elsewhere. A number of phones are already running VoLTE. However, a number of these may be hard to get in the US or expensive. For example, the Fairphone 5 can run VoLTE in the US. Trying to find one in the US may be difficult or expensive. That is part of the reason why we are trying to get this port up and running. This could also help our European friends and others if their carrier has not dropped the Google Pixel 3a or does not include VoLTE Roaming.

Unfortunately, the original developer's carrier dropped the Google Pixel 3a, and this is the main reason why this port is unfinished. We already have confirmed that some carriers in the US still support the Google Pixel 3a and VoLTE Roaming. Therefore, we can continue this project for the original developer. We are always looking for people to help test and contribute!

mr_growl

@atarilinux Here's what /proc/cmdline says for lineage 19.1 on Bonito:

rcupdate.rcu_expedited=1 rootwait ro init=/init androidboot.bootdevice=7c4000.sdhci androidboot.baseband=sdm androidboot.keymaster=1 msm_drm.dsi_display0=dsi_sofef00_sdc_1080p_cmd_display::timing0 androidboot.force_normal_boot=1 androidboot.serialno=99BAX0K5LP androidboot.slot_suffix=_a androidboot.slot_retry_count=0 androidboot.slot_successful=no androidboot.hardware.platform=sdm670 androidboot.hardware=bonito androidboot.revision=MP1.0 androidboot.bootloader=b4s4-0.4-8048689 androidboot.hardware.sku=G020A androidboot.hardware.radio.subtype=2 androidboot.hardware.dsds=0 androidboot.secure_boot=PRODUCTION androidboot.cdt_hwid=0x05032802 androidboot.hardware.majorid=0x03 androidboot.dtb_idx=0 androidboot.dtbo_idx=8 androidboot.bootreason=reboot androidboot.hardware.ddr=4GB,Hynix,LPDDR4X androidboot.ddr_info=Hynix androidboot.ddr_size=4GB androidboot.hardware.emmc=64GB,SKHynix androidboot.cid=00000001 androidboot.boottime=0BLE:530,1BLL:62,1BLE:446,2BLL:126,2BLE:579,SW:10020,KL:1,KD:106,ODT:117,AVB:496,AFTL:0 androidboot.ramdump=disabled androidboot.blockchain=disabled usbcfg.suzyq=disabled androidboot.hardware.pcbcfg=BPPV androidboot.hardware.devcfg=B4VP root=PARTUUID=366e8a1b-1c20-45e6-b794-df754b290cfe androidboot.verifiedbootstate=orange androidboot.aftlstate=8 printk.devkmsg=on msm_rtb.filter=0x237 ehci-hcd.park=3 service_locator.enable=1 firmware_class.path=/vendor/firmware cgroup.memory=nokmem lpm_levels.sleep_disabled=1 loop.max_part=7 androidboot.boot_devices=soc/7c4000.sdhci androidboot.super_partition=system buildvariant=userdebug console=null

Is that what you were looking for?