NX production module not detecting external sd card reader

[vtotalrecall]

I’m trying to do what this user did (same NCB00 carrier board) but with a Jetson NX Production module: How to prepare root fs on microSD card to boot production module from external SD card?

But, the NX is not able to detect a plain ext4 formatted SD card. The SD card is working on other Ubuntu machines, so I believe the issue is with the reader itself. The user mentions editing/replacing the standard dtb file. From other posts, it seems that the sdhci for sdmmc3 is sometimes disabled, so i’m assuming that the dtb file modification enables that?

I checked /proc/ on my jetson and saw that sdhci@3440000 and sdhci@3400000 were disabled and sdhci@3460000 is enabled. I’m using Jetpack 4.6.2, and the dtb file being flashed is the “tegra194-p3668-all-p3509-0000.dtb”. I decompiled it and saw that both 3400… and 34400… had their status set to “disabled”.

My question is: do I just set sdhci@34400… to “okay”, replace the original dtb file, and reflash?

[vtotalrecall]

do I just set sdhci@34400… to “okay”, replace the original dtb file, and reflash?

This worked. My NCB00 can detect the SD card slot. For people who also come across this problem, here is what I did:

1. Flash with your default image and check your flash logs for what dtb files are being used
2. Go to the proper dtb file and decompile it using dtb: Build dtb files for jetson nano
3. Look for sdhci@3440000 and set status to “okay”, save and recompile back with the same link in step 2
4. Replace the old dtb and reflash

Hopefully this doesn’t cause downstream issues.

[kayccc]

Glad to know issue resolved, thanks for the sharing!

[vtotalrecall]

If anyone is confused on how to get the NX production module with the NCB00 SD card, follow this documentation: https://docs.nvidia.com/jetson/archives/l4t-archived/l4t-3261/index.html#page/Tegra%20Linux%20Driver%20Package%20Development%20Guide/flashing.html#wwpID0E01O0HA

But instead of the given flash command, flash with something like this: sudo BOOTDEV=mmcblk1p1 ./flash.sh -C nv-auto-config jetson-xavier-nx-devkit-emmc mmcblk1p1 where mmcblk1p1 is the SD card. It worked for me.