YODAI

1. https://github.com/apritzel/sunxi-fw
2.  "adb reboot bootloader" takes you to fastboot if android boots up, "fastboot" if you are at u-boot terminal. See help for list of u-boot commands, I do not know that much about it but you can feed the list to AI and see if something useful comes up.
 
So to get gpu acceleration going, we need to get this 6.18.19 kernel booted https://github.com/NickAlilovic/build/releases/tag/Radxa-Cubie-A7A-A7Z-A7S-Mainline-V0.1
Have any ideas on why I cannot get any mainline kernels to boot  @Nick A
i tried "setenv bootargs console=ttyS0,115200 earlycon=uart,mmio32,0x02500000,115200 keep_bootcon ignore_loglevel debug clk_ignore_unused"
 

You can find the pinout at https://linux-sunxi.org/MicroSD_Breakout : CD is rx, CLK is tx and GND. There is a risk that using 3.3 v TTL levels on the tf card slot could fry the microsd controller so I would suggest getting the 1.8V version I mentioned earlier.
 
So here is how I boot debian Trixie these days: (still need to figure out how to automate this but I do not know how yet using u-boot)
setenv bootargs console=ttyAS0,115200 root=/dev/sda28 rw rootwait init=/sbin/init clk_ignore_unused sunxi_flash read 4007F000 boot_a sunxi_flash read 4fa00000 dtbo_a fdt addr 0x4fa00000 bootm 4007F000 - 4fa00000  
Or to automagically boot:
setenv bootargs 'console=ttyAS0,115200 root=/dev/sda28 rw rootwait init=/sbin/init clk_ignore_unused' setenv distro_bootcmd 'sunxi_flash read 4007F000 boot_a; sunxi_flash read 4fa00000 dtbo_a; fdt addr 0x4fa00000; bootm 4007F000 - 4fa00000' saveenv  
Write dtb:
dtc -I dtb -O dts -o tablet.dts tablet_patched.dtb dd if=tablet_patched.dtb of=/dev/sda24  status=progress conv=fsync dd if=tablet_patched.dtb of=/dev/sda25  status=progress conv=fsync You need these on host:
sudo apt update sudo apt install debootstrap qemu-user-static
How to prepaire the rootfs which will be flashed to userdata using fastboot:
fallocate -l 8G teclast_trixie.img mkfs.ext4 -b 4096 teclast_trixie.img sudo mount -o loop teclast_trixie.img /mnt/trixie sudo mount --bind /dev /mnt/trixie/dev sudo mount --bind /sys /mnt/trixie/sys sudo mount --bind /proc /mnt/trixie/proc sudo debootstrap --arch=arm64 trixie /mnt/trixie http://deb.debian.org/debian sudo chroot /mnt/teclast /bin/bash passwd root echo "t60" > /etc/hostname apt update apt install build-essential kmod # you will need to install bunch of others but not more than 3 GB I think because fastboot wont reliably transfer more exit sudo fastboot erase userdata sudo fastboot flash userdata teclast_trixie.img  
How to do the raxda kernel:
./magiskboot unpack boot.img cp ../../raxda_kernel.img kernel ./magiskboot repack boot.img new_boot.img sudo fastboot flash boot_a new_boot.img sudo fastboot flash boot_b new_boot.img  
Wifi driver is a bit complicated(TBD):
 
modprobe aic8800_bsp modprobe aic8800_fdrv ip link show wlan0  
Here are the stock partitions:
root@t60:~# blkid  /dev/sda26: SEC_TYPE="msdos" UUID="2200-140B" BLOCK_SIZE="4096" TYPE="vfat" PARTLABEL="media_data" PARTUUID="a0085546-4166-744a-a353-fca9272b8e5e" /dev/sda22: UUID="dd7fd886-b74f-41cf-a5b1-bf1b47afaf8c" BLOCK_SIZE="4096" TYPE="ext4" PARTLABEL="treadahead" PARTUUID="a0085546-4166-744a-a353-fca9272b8e5a" /dev/sda1: SEC_TYPE="msdos" LABEL="Volumn" BLOCK_SIZE="512" TYPE="vfat" PARTLABEL="bootloader_a" PARTUUID="a0085546-4166-744a-a353-fca9272b8e45" /dev/sda23: SEC_TYPE="msdos" UUID="4019-0FB8" BLOCK_SIZE="4096" TYPE="vfat" PARTLABEL="private" PARTUUID="a0085546-4166-744a-a353-fca9272b8e5b" /dev/sda21: UUID="a5aa7e72-84f0-40c4-9693-2a2ad5896309" BLOCK_SIZE="4096" TYPE="ext4" PARTLABEL="metadata" PARTUUID="a0085546-4166-744a-a353-fca9272b8e59" /dev/sda28: UUID="f84bc812-d087-4cba-a90f-d045d40d2e44" BLOCK_SIZE="4096" TYPE="ext4" PARTLABEL="userdata" PARTUUID="a0085546-4166-744a-a353-fca9272b8e60" /dev/sda4: PARTLABEL="env_b" PARTUUID="a0085546-4166-744a-a353-fca9272b8e48" /dev/sda16: PARTLABEL="vbmeta_system_b" PARTUUID="a0085546-4166-744a-a353-fca9272b8e54" /dev/sda2: PARTLABEL="bootloader_b" PARTUUID="a0085546-4166-744a-a353-fca9272b8e46" /dev/sda24: PARTLABEL="dtbo_a" PARTUUID="a0085546-4166-744a-a353-fca9272b8e5c" /dev/sda14: PARTLABEL="vbmeta_b" PARTUUID="a0085546-4166-744a-a353-fca9272b8e52" /dev/sda12: PARTLABEL="misc" PARTUUID="a0085546-4166-744a-a353-fca9272b8e50" /dev/sda9: PARTLABEL="init_boot_a" PARTUUID="a0085546-4166-744a-a353-fca9272b8e4d" /dev/sda20: PARTLABEL="empty" PARTUUID="a0085546-4166-744a-a353-fca9272b8e58" /dev/sda10: PARTLABEL="init_boot_b" PARTUUID="a0085546-4166-744a-a353-fca9272b8e4e" /dev/sda7: PARTLABEL="vendor_boot_a" PARTUUID="a0085546-4166-744a-a353-fca9272b8e4b" /dev/sda19: PARTLABEL="frp" PARTUUID="a0085546-4166-744a-a353-fca9272b8e57" /dev/sda5: PARTLABEL="boot_a" PARTUUID="a0085546-4166-744a-a353-fca9272b8e49" /dev/sda27: PARTLABEL="pstore" PARTUUID="a0085546-4166-744a-a353-fca9272b8e5f" /dev/sda17: PARTLABEL="vbmeta_vendor_a" PARTUUID="a0085546-4166-744a-a353-fca9272b8e55" /dev/sda3: PARTLABEL="env_a" PARTUUID="a0085546-4166-744a-a353-fca9272b8e47" /dev/sda25: PARTLABEL="dtbo_b" PARTUUID="a0085546-4166-744a-a353-fca9272b8e5d" /dev/sda15: PARTLABEL="vbmeta_system_a" PARTUUID="a0085546-4166-744a-a353-fca9272b8e53" /dev/sda13: PARTLABEL="vbmeta_a" PARTUUID="a0085546-4166-744a-a353-fca9272b8e51" /dev/sda11: PARTLABEL="super" PARTUUID="a0085546-4166-744a-a353-fca9272b8e4f" /dev/sda8: PARTLABEL="vendor_boot_b" PARTUUID="a0085546-4166-744a-a353-fca9272b8e4c" /dev/sda6: PARTLABEL="boot_b" PARTUUID="a0085546-4166-744a-a353-fca9272b8e4a" /dev/sda18: PARTLABEL="vbmeta_vendor_b" PARTUUID="a0085546-4166-744a-a353-fca9272b8e56"  
tablet.dts

Howdy. if you have the tf uart adapter thingy, by the time it shows that on screen you are at the u-boot prompt where you can do what you want. e.g. start fastboot. I believe this tablet cannot be bricked because you can always enter FEL mode and use phoenixsuit. It can be maddeningly difficult to phoenixsuit to flash cold tablet but i recall it was like this: press and hold vol+ and power, plug usb cable with phoenixsuite ready to flash. release power button and vol+ few seconds later.