Dealing with custom hardware on x86

From: Chris Packham
Date: Tue Nov 09 2021 - 22:11:31 EST


Hi,

I'm about to start a project involving custom hardware using an x86 CPU.
Complicating things somewhat we will have a CPU board supplied by a 3rd
party vendor using a COM Express type 7 connector which will plug in to
the board we're designing (actually 2 different boards each with some
modular aspects) .

Coming from an embedded (mostly ARM) background I'm used to describing
the hardware via a devicetree and dealing with plug-in modules by
loading devicetree overlays. How do people achieve this kind of thing on
x86?

I gather ACPI is involved somewhere but the knowledge that the BIOS has
will go as far as the COM Express header and somehow we'll have to tell
the kernel about the various non-probeable (mostly i2c) devices on our
board which is kind of where I'm stuck. Any pointers would be greatly
appreciated.

Thanks,
Chris