410c-sdcard-developer-buster not loading wcn36xx

Products Support DragonBoard410c
#1

Hello,
I’ve been trying to use the developer image from a sdcard of the available releases of buster (359, 528 and 660).

The image works, I can boot from the sdcard. However, in all versions there is no usable kernel module for the wireless interface.

When I try to load the module, there seems to be a mismatch of kernel version:

root@linaro-developer:~# modprobe wcn36xx
modprobe: ERROR: …/libkmod/libkmod.c:586 kmod_search_moddep() could not open moddep file ‘/lib/modules/4.9.56-linaro-lt-qcom/modules.dep.bin’
modprobe: FATAL: Module wcn36xx not found in directory /lib/modules/4.9.56-linaro-lt-qcom
root@linaro-developer:~#
root@linaro-developer:~#
root@linaro-developer:~# ls -l /lib/modules/
total 4
drwxr-xr-x 3 root root 4096 Feb 7 2018 4.14.0-qcomlt-arm64
root@linaro-developer:~#
root@linaro-developer:~#
root@linaro-developer:~# uname -a
Linux linaro-developer 4.9.56-linaro-lt-qcom #3 SMP PREEMPT Mon Nov 12 14:56:55 CST 2018 aarch64 GNU/Linux
root@linaro-developer:~#

Any suggestion?

#2

There is indeed a misalignment between the booted kernel and the rootfs modules versions. Could you please try the latest release: https://releases.linaro.org/96boards/dragonboard410c/linaro/debian/20.07/
And check if you reproduce the issue. Is it on dragonboard 410c?

#3

Thank you for your answer Loic.

I tested the latest release and the issue remains:

root@linaro-developer:~# uname -a
Linux linaro-developer 4.9.56-linaro-lt-qcom #3 SMP PREEMPT Mon Nov 12 14:56:55 CST 2018 aarch64 GNU/Linux
root@linaro-developer:~# modprobe wcn36xx
modprobe: FATAL: Module wcn36xx not found in directory /lib/modules/4.9.56-linaro-lt-qcom
root@linaro-developer:~# ls -l /lib/modules/
total 4
drwxr-xr-x 3 root root 4096 Jul 4 2020 5.7.0-qcomlt-arm64

No, it is the db4iot. But the WIFI hardware is the same, so I thought there would be no difference, at least in loading the module in the correct kernel version.

Thank you again.

#4

@alimon do you confirm boot partition of the sdcard-developer image is correctly aligned with modules in the rootfs partition?

#5

@Loic Just did it and everything looks fine, recently I fixed the sdcard rootfs mount for this release. Log at https://pastebin.com/syGTpfmq .

@Antonio_Gonzalez Looks like your board is loading the boot image from eMMC,

Do you have the sdcard boot pin enabled?

Which is the status of your boot emmc partition?, can you delete it? and try again.
$ fastboot erase boot

Do you have the latest bootloader installed?
http://releases.linaro.org/96boards/dragonboard410c/linaro/rescue/20.07/dragonboard-410c-bootloader-emmc-linux-145.zip