Avoid ACPICA if at all possible. It's one garbage tier cluster fuck of bad design, horrible documentation and downright misleading and wrong code

It's meant to consist of an ASL compiler, disassembler, debugger, dumper, various user space utitilies and a kernel resident OSPM implementation *if* you can figure out what belongs to what. Even just compiling this pile of trash is a mystery in itself. Think you need the source files in source/common? EEEEH, wrong. Well, at least partially since most of them seem to be for the user space stuff..? Other ones *are* needed on the other hand. At least the disassembler and/or debugger and/or dumper components seem to reference them. Not that I could figure out how to compile those anyways. The real path to your goal seems to be to ignore a seemingly arbitrary subset of source and header files until your linker stops complaining

There's also a bunch of configuration defines, some of which *you* define, some defined *for* you, based on again others. Of course most of them do stupid shit. Enabling the debugger automatically enables debug logging. Enabling the disassembler force enables debug allocation tracking... What?

The code itself isn't of much help either. Looking in "os_specific/service_layers" you find what looks to be reference implementations of acpica functions in certain os' like windows and unix. Of course I had a look because AcpiOsReadMemory is supposed to read physical memory and I don't know how I would even implement that. But hey, osunixxf.c (xf for interface... of course) should tell me. I'll let you see for yourself in the attached image. Apparently it does fuck all and just returns AE_OK. No error, no logging, no nothing. Just ok. As you can imagine, AcpiOsWriteMemory doesn't do much more either.
...okay so maybe physical memory accesses aren't actually used and these functions are some sort of relic from past times? Nope! They are absolutely necessary for doing low level device interaction. WTF. So finally I went to the linux source and checked how *they* implemented them, and just as I thought, these functions are anything but no-ops...
...So for what fucking reason do these stupid interface implementations even exist but to purposefully mislead you?? They aren't used for fucking anything! As far as I know Windows doesn't even *use* ACPICA and Linux have their own fork with working implementations... They just sit there, just to tell you how to NOT do it

So that's some of my thoughts about ACPICA. Note that I haven't even used it as a library yet, I just got it to compile and link and it already fucked with me this much.
There's also so much more I didn't mention like that you *have* to modify the acpica source in order to get your own platform header working (else #error) eventhough the docs explicitely instruct you not too but you get the point

Don't use ACPICA if you don't have to. Save your sanity for something that's worth it