Clone the branch pocketgo-s30 of our u-boot repo:

$ git clone -b pocketgo-s30 https://github.com/PocketGo-S30-CFW/u-boot.git
$ cd u-boot
$ make PocketGo_s30_a33_defconfig
$ make CROSS_COMPILE=arm-linux-gnueabihf- -j17

Note: change the -j17 to your number of cores+1 (e.g. 8 cores -> -j9)

The build should generate a u-boot-sunxi-with-spl.bin u-boot file that can be used via USB with sunxi-fel or flashed to a SDCard

Once u-boot is compiled, you can either boot via tethered USB or flashed SD card.

USB (sunxi-fel) BOOT

Sunxi-fel is part of the sunxi-tools package, you can install it by checking out their repo: https://github.com/linux-sunxi/sunxi-tools.

After sunxi-fel is installed you need to put the console in FEL mode. The Pocket-Go S30 does not have a dedicated recovery/reset button, so you can use the fel-sdboot.sunxi image and flash it to a SDcard with:

$ get https://github.com/linux-sunxi/sunxi-tools/raw/master/bin/fel-sdboot.sunxi
$ sudo dd if=fel-sdboot.sunxi of=/dev/sdX bs=1024 seek=8

Note: replace sdX with your sdcard device (you can find it with fdisk -l)

Power down the Pocket-Go S30, insert the new SDCARD that you flashed with fel-sdboot.sunxi in it, and connect your UART to your compture.

Then you can boot the console via USB:

sunxi-fel -v -p uboot u-boot-sunxi-with-spl.bin

If you have UART connected, you will see the following output:

U-Boot SPL 2022.01-rc2-dirty (Nov 23 2021 - 16:07:52 +0000)
DRAM: 512 MiB
Trying to boot from FEL


U-Boot 2022.01-rc2-dirty (Nov 23 2021 - 16:07:52 +0000) Allwinner Technology

CPU:   Allwinner A33 (SUN8I 1667)
Model: PocketGo S30
DRAM:  512 MiB
WDT:   Not starting watchdog@1c20ca0
MMC:   mmc@1c0f000: 0, mmc@1c11000: 1
Loading Environment from FAT... Unable to use mmc 0:2... Setting up a 320x480 lcd console (overscan 0x0)
In:    serial
Out:   vidconsole
Err:   vidconsole
Allwinner mUSB OTG (Peripheral)
Net:   eth0: usb_ether
starting USB...
Bus usb@1c1a000: USB EHCI 1.00
Bus usb@1c1a400: USB OHCI 1.0
scanning bus usb@1c1a000 for devices... 1 USB Device(s) found
scanning bus usb@1c1a400 for devices... 1 USB Device(s) found
       scanning usb for storage devices... 0 Storage Device(s) found
Hit any key to stop autoboot:  0

SDCARD BOOT

Another option is to flash the compiled u-boot (u-boot-sunxi-with-spl.bin) to the sdcard with:

sudo dd if=u-boot-sunxi-with-spl.bin of=/dev/sdX bs=1024 seek=8

Note: replace sdX with your sdcard device (you can find it with fdisk -l)

Power down the Pocket-Go S30, insert the new SDCARD that you flashed with u-boot-sunxi-with-spl.bin. Connect your UART and turn on your console. You will see something like:

PocketGo S30 CFW Boot - Click to expand!

```console U-Boot SPL 2022.01-rc2-00024-g3144ba23bf-dirty (Nov 20 2021 - 04:03:00 +0000) DRAM: 512 MiB Trying to boot from MMC1 U-Boot 2022.01-rc2-00024-g3144ba23bf-dirty (Nov 20 2021 - 04:03:00 +0000) Allwinner Technology CPU: Allwinner A33 (SUN8I 1667) Model: PocketGo S30 DRAM: 512 MiB WDT: Not starting watchdog@1c20ca0 MMC: mmc@1c0f000: 0, mmc@1c11000: 1 Loading Environment from FAT... *** Warning - bad CRC, using default environment Setting up a 1024x600 lcd console (overscan 0x0) In: serial Out: vidconsole Err: vidconsole Allwinner mUSB OTG (Peripheral) Net: eth0: usb_ether starting USB... Bus usb@1c1a000: USB EHCI 1.00 Bus usb@1c1a400: USB OHCI 1.0 scanning bus usb@1c1a000 for devices... 1 USB Device(s) found scanning bus usb@1c1a400 for devices... 1 USB Device(s) found scanning usb for storage devices... 0 Storage Device(s) found Hit any key to stop autoboot: 0 => setenv bootargs console=ttyS0,115200 earlyprintk=serial,ttyS1,115200 debug loglevel=7 rootwait root=/dev/mmcblk0p1 => load mmc 0 0x43000000 boot/sun8i-a33-olinuxino.dtb 21702 bytes read in 3 ms (6.9 MiB/s) => load mmc 0 0x42000000 boot/zImage 4087568 bytes read in 172 ms (22.7 MiB/s) => bootz 0x42000000 - 0x43000000 Kernel image @ 0x42000000 [ 0x000000 - 0x3e5f10 ] ## Flattened Device Tree blob at 43000000 Booting using the fdt blob at 0x43000000 Using Device Tree in place at 43000000, end 430084c5 Starting kernel ... [ 0.000000] Booting Linux on physical CPU 0x0 [ 0.000000] Linux version 5.0.0 (acmeplus@endymion) (gcc version 6.3.1 20170404 (Linaro GCC 6.3-2017.05)) #3 SMP Fri Nov 26 1 [ 0.000000] CPU: ARMv7 Processor [410fc075] revision 5 (ARMv7), cr=10c5387d [ 0.000000] CPU: div instructions available: patching division code [ 0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache [ 0.000000] OF: fdt: Machine model: Olimex A33-OLinuXino [ 0.000000] printk: bootconsole [earlycon0] enabled [ 0.000000] Memory policy: Data cache writealloc [ 0.000000] cma: Reserved 16 MiB at 0x5d000000 [ 0.000000] psci: probing for conduit method from DT. [ 0.982066] hub 1-0:1.0: 1 port detected [ 0.986741] ohci-platform 1c1a400.usb: Generic Platform OHCI controller [ 0.993386] ohci-platform 1c1a400.usb: new USB bus registered, assigned bus number 2 [ 1.001344] ohci-platform 1c1a400.usb: irq 27, io mem 0x01c1a400 [ 1.076061] hub 2-0:1.0: USB hub found [ 1.079842] hub 2-0:1.0: 1 port detected [ 1.084569] usb_phy_generic usb_phy_generic.0.auto: usb_phy_generic.0.auto supply vcc not found, using dummy regulator [ 1.095330] usb_phy_generic usb_phy_generic.0.auto: Linked as a consumer to regulator.0 [ 1.103660] musb-hdrc musb-hdrc.1.auto: MUSB HDRC host driver [ 1.109404] musb-hdrc musb-hdrc.1.auto: new USB bus registered, assigned bus number 3 [ 1.118413] hub 3-0:1.0: USB hub found [ 1.122213] hub 3-0:1.0: 1 port detected [ 1.127172] sun8i-a33-pinctrl 1c20800.pinctrl: 1c20800.pinctrl supply vcc-pf not found, using dummy regulator [ 1.137291] sunxi-mmc 1c0f000.mmc: Linked as a consumer to regulator.1 [ 1.144328] sunxi-mmc 1c0f000.mmc: Got CD GPIO [ 1.174253] sunxi-mmc 1c0f000.mmc: initialized, max. request size: 16384 KB [ 1.181508] simple-framebuffer 5e000000.framebuffer: Linked as a consumer to regulator.6 [ 1.189675] simple-framebuffer 5e000000.framebuffer: framebuffer at 0x5e000000, 0x96000 bytes, mapped to 0x(ptrval) [ 1.200136] simple-framebuffer 5e000000.framebuffer: format=x8r8g8b8, mode=320x480x32, linelength=1280 [ 1.212411] Console: switching to colour frame buffer device 40x30 [ 1.221094] simple-framebuffer 5e000000.framebuffer: fb0: simplefb registered! [ 1.228459] sun6i-rtc 1f00000.rtc: setting system clock to 1970-01-01T00:00:14 UTC (14) [ 1.236793] ALSA device list: [ 1.239759] No soundcards found. [ 1.244068] Waiting for root device /dev/mmcblk0p1... [ 1.278480] mmc0: host does not support reading read-only switch, assuming write-enable [ 1.288323] mmc0: new high speed SDXC card at address 59b4 [ 1.295033] mmcblk0: mmc0:59b4 58.2 GiB [ 1.301732] mmcblk0: p1 [ 1.336164] EXT4-fs (mmcblk0p1): mounted filesystem with ordered data mode. Opts: (null) [ 1.344364] VFS: Mounted root (ext4 filesystem) readonly on device 179:1. [ 1.351730] devtmpfs: mounted [ 1.355798] Freeing unused kernel memory: 1024K [ 1.381592] Run /sbin/init as init process [ 1.455036] random: fast init done [ 1.458519] EXT4-fs (mmcblk0p1): re-mounted. Opts: (null) Starting syslogd: OK Starting klogd: OK Running sysctl: OK Initializing random number generator: OK Saving random seed: [ 1.566874] random: dd: uninitialized urandom read (512 bytes read) OK Starting network: OK Welcome to A33 OLinuXino! A33-olinuxino login: root ```