Felix Held has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/42434 )
Change subject: x86/lapic: Set EXTINT on BSP only ......................................................................
Patch Set 4:
Patch Set 4:
Felix, I got an suggestion to have LINT0 set as ExtINT on BSP, but all APs should mask ExtINT then (not set to fixed delivery). It should be the correct solution. Credits to Andrew Cooper.
Masking vs. masking and then setting it to fixed delivery mode should do the same though, since LAPIC_DELIVERY_MODE_FIXED is defined as 0 << 8. Or am i missing something here?
When applying the patch I still get some additional delay from seabios starting to the first screen of the live Linux system on the USB stick where i can optionally change the kernel parameters on Mandolin; haven't tested on my x230 yet.
I'm not sure if this really is a coreboot issue or if the issue is on the seabios side or even a bootloader issue. I don't see an obvious problem with the coreboot patch though, but this part of the x86 arch is definitely not something I'm too familiar with.