I have Windows booting on a KBL CrOS device, and looking at my tree, pretty sure the only change I have that would potentially address that error is adding the pcon value to the IGD ACPI OpRegion header:

https://github.com/MattDevo/coreboot/commit/3349065354709c852765555168272469797dd3f6

there were a few others but they've all since been merged upstream

On Wed, Apr 25, 2018 at 6:00 PM Alex Feinman <alexfeinman@hotmail.com> wrote:

I've built a Coreboot image (from the HEAD) for my custom Kaby Lake board. The build uses Chrome EC and is based on kblrvp3 mainboard configuration. Linux runs fine, but when I attempt to install Windows 10 (or boot a preinstalled Windows image from USB) I instantly get ACPI_BIOS_ERROR (0xC00000A5). There is a Microsoft document that provides a large amount of possible reasons for this error, however I can't even narrow it down because cleverly Windows 10 no longer prints the bug check parameters, at least not in this case.

I would appreciate some pointers if possible.

Thank you

Alex

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