Device Driver Debugging

[shreyank amartya]

Hi,

I have modified a driver source for eMMC controller (added a new device in
the table) and I want to debug an issue (HS400 mode not working) with the
device. I compiled and loaded the sdhci_acpi module, now I'm new to FreeBSD
and device driver development, so I was wondering what are the ways I can
debug this issue, any resources, and utilities that would make it easier to
debug this problem.

I see there is a debug flag (hw.sdhci_acpi.debug), which I enabled using
sysctl, but I'm not sure how to utilize it.

Any help is appreciated :)

Thanks
Shreyank