I also seem more comfortable with Mobian than with Arch. I read this and several other topics and wan unable to boot any Mobian images flashed to SD card. The problem is: these images do not have u-boot installed (they expect u-boot to be flashed in SPI) and also their partition scheme leaves no room to install u-boot. I even tried to create a custom image with bootfs and rootfs partitions moved so that the first 16 MB of the image is clean and it is possible to put u-boot there. I had a partial success. But this procedure is very inconvenient.
Then, I found this document:
https://github.com/u-boot/u-boot/blob/ma...ip.rst#spi
In the section 1, subtitle SPI I found:
So, I just flashed the Mobian image to SD card with Etcher and then copied u-boot-rockchip-spi.bin file to the bootfs partition (1st) on SD. And voila, Mobian successfully starts from SD card.
The u-boot is already flased in SPI of PineTab2 and its searches for SD card before eMMC. So, no UART adapter is necessary. If you want to see the boot logs, you can of course attach it, but do not switch on the SD boot maskrom on the adapter.
Then, I found this document:
https://github.com/u-boot/u-boot/blob/ma...ip.rst#spi
In the section 1, subtitle SPI I found:
Quote:Write u-boot-rockchip-spi.bin to offset 0 of SPI flash.
Copy u-boot-rockchip-spi.bin into SD card and boot from SD:
Code:sf probe
load mmc 1:1 $kernel_addr_r u-boot-rockchip-spi.bin
sf update $fileaddr 0 $filesize
So, I just flashed the Mobian image to SD card with Etcher and then copied u-boot-rockchip-spi.bin file to the bootfs partition (1st) on SD. And voila, Mobian successfully starts from SD card.
The u-boot is already flased in SPI of PineTab2 and its searches for SD card before eMMC. So, no UART adapter is necessary. If you want to see the boot logs, you can of course attach it, but do not switch on the SD boot maskrom on the adapter.