I am experiencing problems using the AMT SOL feature on a NUC5i5MYHE. Here's the symptom:
Windows 7 just hangs when using the port (e.g., using PowerShell). If I configure a timeout, I just get the timeout, but no serial output.
Linux experiences a long delay after printing the characters, but it also complains about unexpected interrupts. Using the "irqpoll" cmdline option, it works fine.
A baremetal kernel works fine without interrupts, and even the interrupt-driven configuration works if you find the correct interrupt to use.
Interestingly, the interrupt that both Linux and Windows report (17) does not match the actual one that can be observed (19). Furthermore, IRQ 19 is also the SATA interrupt, which makes me wonder if 17 is actually the correct one, but for some reason it is not being used.
This happens on several machines of this model, and I have tried multiple BIOS versions, including the most recent one (86A.0038).
Has anyone else seen this? I would really appreciate some help