RPi 4 and UEFI Sytem Table firmware settings.

[Ramiro Aceves <ea1abz%gmail.com@localhost>]

Hello,

I have been using my RPi4 with the UEFI 1.50 firmware from 
https://github.com/pftf/RPi4 since NetBSD 11.0_RC3, and everything has been 
working fine.

Yesterday I upgraded to RC5 from RC3 using sysupgrade and usual tricks, and by 
mistake I re-extracted the UEFI firmware over /boot and overwrote RPI_EFI.fd (I 
forgot to back it up first). After rebooting, I had to connect a HDMI monitor to 
adjust the default 3 GB RAM limit and boot device order.

While doing so, I noticed a BIOS setting that I had previously ignored:

Device Manager
  Raspberry Pi Configuration
    System Table Mode

The available options are:

ACPI
ACPI + Device Tree
Device Tree

I have left the default value (ACPI) unchanged, and everything seems to be 
working correctly so far.

My question is: what is the recommended option for my setup? What are the 
practical advantages or disadvantages of each mode, and what could improve or 
potentially break by choosing one over the others?

Thanks a lot.

Ramiro.