Flash only RootFS into NVME and kernel,bootloader into EMMC. JP 4.6

[bsp_dev]

Thank you for answering,
I think we have a small misunderstanding so I’ll list all the steps , that according to my understanding from your answers , I have to do:

1. Edit extlinux.conf on my host to specify the root path and point to my NVME(SSD) device.
2. Flash rootfs only (APP partition) into my NVME device I have in my custom board (using the initrd “method”). The NVME and nx module are connected by PCIe.
3. Flash rest of partitions (kernel,bootloader and all the rest) into emmc (using flash.sh)
4. Cboot will find APP partition in my NVME device and the extlinux.conf
5. extlinux.conf doesnt contain LINUX var , hence cboot will load kernel from kernel partition flashed in the emmc.

Is that correct?

[WayneWWW]

Yes, it sounds correct. So you don’t want to put a rootfs to your emmc which contains a extlinux.conf?

If so, then yes, you can try your steps.

[bsp_dev]

The whole purpose from the beginning was to put the rootfs in one place and the kernel in another. I don’t want them to be in the same device.

Last missing step in the above procedure:
If I want to flash only the rootfs - I can use its partition name. (step 2)

If I want to flash all the partitions except the APP partition - how can I do that? (step 3)
I don’t want to flash the rootfs twice into two places by mistake.
I need a way to tell the flasher to flash all of the partitions into the emmc except the APP partition (which is already flashed in the NVRAM)

[WayneWWW]

Please check the Linux_for_Tegra/bootloader/t186ref/cfg.

There are the xml files which contain the partition layouts. This file “flash_l4t_t194_qspi_p3668.xml” will flash the qspi with bootloader only.

After you flash QSPI, you could use -r -k kernel in flash.sh to flash kernel partition only. But at that time, you need to use flash_l4t_t194_spi_emmc_p3668.xml, so that it will flash to emmc this time.

[WayneWWW]

or you can just remove APP partition from flash_l4t_t194_spi_emmc_p3668.xml.

[bsp_dev]

and what about the rest of the partitions? (we have many more than kernel and APP…)
where they will be flashed?

I just want to make sure I don’t flash any partition (not just APP) twice…