[coreboot] How to improve the boot time of the Asus KGPE-D16?

[Timothy Pearson]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 03/03/2017 04:14 PM, Paul Menzel via coreboot wrote:
> Dear Daniel,
> 
> 
> Am Freitag, den 03.03.2017, 10:52 +0100 schrieb Daniel Kulesz:
> 
>>> I think most of the time is spent in RAM initialization.
>>>
>>>    1. Do board owners with similar amount of memory (independent of the
>>>       board) have similar numbers?
>>>    2. What are the ways to improve that? Is it possible? For example, can
>>>       the modules be probed in parallel (if that isn?t done already)?
>>
>> Regarding 1: I am running 128GB in 8GB modules (LRDIMMs) and
>> experiencing a similar issue. With just two UDIMMs, the boot times
>> are *much* faster.
> 
> That’s good to hear. Do you have concrete numbers?
> 
>> Also, the vendor BIOS is faster from the time you press the poweron
>> button to the time the monitor gets a signal.
> 
> I believe that’s a design decision in coreboot, that the display can
> only be initialized after RAM has been initialized. The vendor firmware
> seems to be able to do it beforehand. (If I am wrong, the vendor
> firmware is really fast in configuring the memory.)

The vendor firmware starts up the display while memory is still being
configured.  As far as I can tell, the graphical ASUS logo is loaded as
part of the proprietary BIOS's romstage-equivalent component, while RAM
is not initialized until that logo is removed from the display.  You can
test this for yourself by noting that the keyboard numlock will not
respond while that logo is displayed, whereas it does respond afterward.

The proprietary BIOS likely uses a proprietary variant of the open AGESA
code in the coreboot tree, and I see no reason its RAM initialization
will be any faster (or slower) than the native RAM initialization
currently used for the KGPE-D16 as both are based on the same BKDG and
use the same general algorithms.

- -- 
Timothy Pearson
Raptor Engineering
+1 (415) 727-8645 (direct line)
+1 (512) 690-0200 (switchboard)
https://www.raptorengineering.com
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/

iQEcBAEBAgAGBQJYuezkAAoJEK+E3vEXDOFbDXkH/Aw+IORZhJdncXFVEn+0Go8s
lRGuYJzcx28XmVLXDYfZACGdAdVRWnc0AYFGUeqJm1oCMoxpKa5zqVfdIMf+2XU6
vo3Qm6nkzAUxp61s2niaOoAwN6G11XsFokeoFDAL+2m9sxxxVgwBiiazQNlUrusu
4S6Z6H9aooJPAEtj/E/HhovJGCb9DCZEyHkT4V+kZc0I0i3i2khktNcgenlkVefU
aNeZQ3aabJ3LMfJLbBEDFHlrFHbjRjU7aDeosTztnR0w+AVa2w6ZbUd5D6Pq8h1X
un7sD+AsBpvKjnTq00d89OD/2glmq4cglGKW+vlNg3xzsiz3eXjGmmRlJKZsTSI=
=Q6T1
-----END PGP SIGNATURE-----