Disabling Intel RST

Hi,

I have a X35G mini-pc from Minisforum. I used to be able to access the NVMe device directly and have Linux on the NVMe disk.

Recently the NVMe device disappeared and I was no longer able to boot Linux.

I put more detail in a blog : X35G Intel RST.

TLDR, the BIOS has no option to change the RST configuration. The goal being enabling AHCI mode ( disable RAID ).

I came across the post on Intel RST EFI RAID and VMD BIOS Modules. I used some of the tools to look at the BIOS for the system.

@Fernando would there a way to change the RST configuration via a UEFI utility ?

For the X35G BIOS, the MMTool lists an Option ROM with Device Path HB0-0:0-0:0-17:0 and VID 0x8086 DID 0x2822. The IDs match a SATA Controller. On Windows there is no such device. The Intel RST controller is reported as 0x8086 0x282A. However that controller has PCIe bus id 00:17.0.
There is another Option ROM for the Graphic and Network controllers. However I am not sure what those Option ROM are about.

How is the RST configuration stored ? Would Option ROM hold some config for RST ?

Thanks for some pointers.