Newbie question about the MNT Pocket reform u-boot loader

Hi all, I don’t have MNT computer yet, but I am thinking about having a Pocket Reform. However, I have some preliminary super basic questions about it.

To my understanding, if I buy a Pocket Reform now, it will come with a RK3588 module, which will contain a processor module and an eMMC card (either with 128 or 256 GB), both sold to the RK3588 module. The eMMC card, will contain at least two partitions. One will contain the U-Boot loader, and the other will contain the last stable Debian. When starting, the processor will look for the U-Boot loader, and this will call the system loader in the Debian partition. The U-Boot loader, needs three files to load Debian, which are indicated on the Pocket Reform Handbook.

The manual said:

The Processor Module will try to load boot code (U-Boot) from eMMC. If that fails, the standard i.MX8M Plus Module can only be booted using a special USB bootloader mode, which currently requires the Ezurio Nit8MP_ENC_CAR carrier board, a USB connection to another computer and the uuu tool from NXP. Please be careful when modifying the boot partition on eMMC because it is hard to recover without a carrier board. Other Processor Modules may have different boot device options—please refer to their specific documentation.

I guess that the i.MX8M module is a module inside the processor in the RK3588 module. I don’t understand what is meant by “failing.” Does it mean that the U-Boot system is somehow corrupted? What it means that “it can only booted using using a special USB bootloader mode […]”? Does it means that the RK3588 module should be mounted on such a specific carrier board where it can be edited and thus fixed, and that this carrier board is not sold with the Pocket Reform?

In case the U-Boot system gets corrupted as described above, can I send the RK3588 module back so it gets fixed or tested?

Hi, I’m sorry that this is confusing. The i.MX8M (and Plus) are different processors from NXP that we used before RK3588 and A311D, see also the table: Modularity—MNT Research GmbH

For RK3588, it works slightly differently. If you erase u-boot on eMMC, the RK3588 ROM will look for a bootloader on SD card. But lets say the u-boot on eMMC is loaded by RK3588 but is broken somehow, and you can’t fix it via serial console, then you would also need to do a similar unbricking procedure via a special USB bootloader mode. But yes, in that case you can also send in the module for reflashing to us. I have to say that this hasn’t happened in the field so far.

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Thank you for your answer. It is good to know how friendly the Pocked Reform is regarding repairing it, and thus minimizing the e-waste production.