How could I try and debug, and hopefully fix, the ACPI tables dumped by acpidump?
If I run acpidump -t, I get:
acpidump: RSDT entry 21 (sig SSDT) is corrupt
I fixed an ACPI problem with an old motherboard. Here, I document the steps I used to repair it:
Trying FreeBSD 12.0 on an old Pentium 4 machine, with Intel D915GAV motherboard, latest BIOS version. Everything seems to be working OK except that I have an ACPI error report in dmesg on boot...