DS3231 RTC module not detected

From: Archimedes Gaviola <archimedes.gaviola_at_gmail.com>
Date: Thu, 17 Feb 2022 15:32:25 UTC
Hi,

I have a DS3231 real-time clock module (
http://wiki.sunfounder.cc/index.php?title=DS3231_Real_Time_Clock_Module_for_Raspberry_Pi)
but cannot be detected with FreeBSD 13.0-RELEASE and 14.0-CURRENT. My
config.txt have this following lines;

dtparam=i2c_arm=on
dtoverlay=i2c-rtc,ds3231

and then I fetched a copy of the i2c-rtc.dtbo file here
https://github.com/raspberrypi/firmware/blob/master/boot/overlays/i2c-rtc.dtbo
and put it in the /boot/msdos/overlays directory.

root@generic:/boot/msdos/overlays # ls -lah
total 208
drwxr-xr-x  1 root  wheel   4.0K Feb 10 10:18 .
drwxr-xr-x  1 root  wheel    16K Jan  1  1980 ..
-rwxr-xr-x  1 root  wheel   1.0K Mar  3  2021 disable-bt.dtbo
-rwxr-xr-x  1 root  wheel   172K Feb 11 06:09 i2c-rtc.dtbo
-rwxr-xr-x  1 root  wheel   1.2K Mar  3  2021 mmc.dtbo
-rwxr-xr-x  1 root  wheel   985B Mar  3  2021 pwm.dtbo

I rebooted my RPi 4B and then dmesg still prompts this message.

Warning: no time-of-day clock registered, system time will not be set
accurately

I have tried this configuration in OpenBSD 6.9 and it is working. Is there
any method with FreeBSD?

I also tried loading the ds3231.ko and enabled in the loader.conf and then
rebooted my system again but still not able to detect the module.

root@generic:~ # kldload ds3231
root@generic:~ # kldstat | grep ds3231
 9    1 0xffff0000d1ab8000    23000 ds3231.ko

Thanks,
Archimedes