Hello Peter,
Thank you for your response!
Cool! And ambitious. :)
Yeah, the project is pretty hacky, to be frank, and will be limited to the setup where SMRAM is from a0000h to bffffh.
In general coreboot makes an attempt to not go overboard with SMM code, in particular the QEMU board code may have almost none, to the point where it's far from representative for modern platforms.
Yes, I'm aware of coreboot's stance on SMM. If I recall correctly, QEMU seemed to have trouble clearing the SMI_STS register. We will likely use hardware to test the setup. You're confirming my fear related to testing SMM in QEMU. I hope we will be able to see more SMM activity on a real board, but I don't know what to expect, as I have trouble finding sources that discuss how SMM is used in the "wild" (besides articles on reversing and exploiting SMM).
Are you aware whether SMM is tested (for new functionality, for instance), and if so, how that is being done? Or is this done by using existing hardware setups? I do not have a lot of experience with low-level hardware.
Thanks for your input :).
Kind regards,
Mick