[coreboot] Asus KGPE-D16 with latest coreboot errors with Unsupported Hardware on Qubes 4 install missing IOMMU?

[Taiidan at gmx.com]

On 12/01/2018 11:56 AM, Nico Huber wrote:
> Hi Pete,
> 
> On 01.12.18 17:21, petecb via coreboot wrote:
>> I'm wondering if my problem is related to not having any SATA drives
>> installed? (I just have a PCI-E SSD). It may be the case that the logic
>> to disable combined mode is not getting triggered in my scenario, yet it
>> would do if there was a SATA drive present.
> 
> it's a configuration issue. If you have nvram settings enabled (CONFIG_
> USE_OPTION_TABLE), you can enable `sata_ahci_mode` with nvramtool.
> 

Ah so that is why it works for me but not for him, since I always
customize my CMOS options :D

> No idea why combined mode is the default, it's only useful for OSes from
> the '90s. It's not about the type of drives (SATA vs PATA) connected but
> how the SATA controller identifies itself to the OS.
AHCI is faster and better as it supports NCQ, TRIM etc.

Conga-rats petey now you can fix it easy! just enable cmos settings in
menuconfig then go to the kgpe-d16 coreboot board directory and change
cmos.default, recompile/flash then reset your CMOS - OR if you already
have use cmos enabled you can simply change it via the cmos tool with
the required iomem=relaxed in the kernel command line.

I would also lower the log/debug level via menuconfig to speed boot
times and maybe change some other things in cmos.default like me

I have
experimental_memory_speed_boost enabled, my 1394 controller set to
disabled and SATA ALPM to enabled.