FreeBSD-12 / i915 on librem13 at purism - hang on suspend after update

[Dirk-Willem van Gulik]

After a routine update to FreeBSD-12.0-RELEASE and a ports update -- I am getting hard hangs on suspend on a librem13 laptop with the i915 chipset (works fine until that point).

Screen lit up but black; does not respond to the off-key/alt-F1/vty and not a peep on serial/network (so likely a fairly hard hang). Have tried both with and without letting it load the firmware.

Does that ring a bell with anyone ? Any clever ways to debug such a hang ?

Dw.

FreeBSD-12.0
drm-fbsd12.0-kmod-4.16.g20181215
drm-kmod-g20181126
gpu-firmware-kmod-g20180825