So it was another occasion for my bimonthly cadence of software update to my BPI-R4. It fell on the release of OpenWrt 25.12.6 and aggressive catch-up on Mediatek’s part on its MTK feeds.
I found MediaTek enabled a hardware feature known as “FE Misc Interrupt”. So unlike up to this moment, we saw a total of five IRQs on the “ethernet” hardware block, now I can see this sixth “FE Misc Interrupt” enabled in my system.
Digging in a bit more tells me exactly when the interrupt will be fired. It’s a feature known as “soft error recovery” or SER as part of MTK’s NETSYS. And it seems so far also offers limited choices to manual recovery from such “soft errors”.
Very interesting so I think I would share.Note that mine is a custom firmware I personally maintain. You may or may not see such feature in your R4.
