I have read some other threads grazing this topic, however I am still in need of some clarification. I’m wondering if it possible to boot a TX1 module and a TX2 module both from the same SD-Card with L4T R28.1 on it.
Both modules would have R28.1 flashed via JetPack on their EMMC. I know that the bootloaders are different between the TX1 and TX2 (https://devtalk.nvidia.com/default/topic/1023392/jetson-tx2/flashing-tx2-with-tx1-jetpack/), but the bootloaders should just remain on the EMMC and load the rootfs.
For the TX1, the process for booting from SD is pretty simple: Cloning the rootfs onto it, then changing the extlinux.conf on the SD so that it loads the rootfs from SD. The bootloader would then, by default, first look at the extlinux.conf on the SD, if it was available. The TX1 would then boot from SD when a card was plugged in, and from EMMC if there wasn’t.
From what I’ve read thus far this process isn’t possible on the TX2. Judging by this thread, it seems that the bootloader on the TX2 doesn’t look at the SD-card first like it did on the TX1, but at the EMMC. Thus the extlinux.conf on the EMMC has to be changed to boot from SD. This however makes it impossible to boot from the EMMC when no SD-card is plugged in and no serial-console is available.
I am fine with this limitation on the TX2 as long as I can still boot from SD on it - since I can then change the contents of the EMMC-extlinux.conf when booted, to allow for booting from the EMMC.
However I found the following:
When I plug in a SD-card with a valid rootfs used to boot on the TX1 to the TX2, the TX2 will not boot. It will boot when the SD-card is not plugged in. I have done no further investigation on this, but it is apparent that the plugged-in SD indeed affects the boot-process, which I (according to the above paragraph) didn’t think it should.
Can someone please clarify my assumptions I’ve gathered so far? And by that, answer the question whether it is possible to boot both modules from the same SD-card. Are there any other differences between the TX1- and the TX2-version of L4T that may prohibit this?