This means that I must use the original kernel, or I can try to boot with the upstream images?
No, this means that the legacy 3.10 kernel does not care about the dtb.img file in the root of the SD card because it cannot load from there. Actually, the dtb is integrated into the kernel.img, which it loads.
But, if you would like to try with my legacy image, I recommend the MXIII-1G image, because this is the only image with 1GB RAM support for an S802 device. In theory, this should boot without any modifications.
wifi doesn't match what I saw (ap6210)
Since the v9.2.8.12 image, this is completely irrelevant, it will probably work, including the bluetooth part...
Quote
LibreELEC v9.2.8.12 (2023-11-20):
...
- S8X2: apply bcmdhd driver update for all devices,
I have access to it by UART, now I'm trying to copy the original boot loader to a USB.
This is completely unnecessary.
- If the toothpick method does not work, but you have UART access, first of all write the image suggested above to an SD card with this program.
When finished, put the SD card into the box. - Interrupt the startup process of uboot, then copy the contents of the aml_autoscript file line by line after the prompt:
setenv bootfromnand 0
setenv upgrade_step 2
setenv startfromsd 'if mmcinfo; then if fatload mmc 0 ${loadaddr} kernel.img; then setenv bootargs ${bootargs} bootfromsd; bootm; fi; fi'
setenv startfromext 'if test ${bootfromnand} = 1; then setenv bootfromnand 0; saveenv; exit; fi; if test ${reboot_mode} = switch_system; then exit; fi; run startfromsd'
setenv bootcmd 'run startfromext; run storeboot'
saveenv
run storeargs
run startfromsd
run recovery
^ If everything went well, you can't paste the last line, because LibreELEC starts after run startfromsd.
However, if this is not the case, please send the messages displayed afterwards.
Don't even try to boot from USB, because loading the kernel doesn't work for S8xx devices.