Fwd: Unfinished unichrome driver

[Andrius V <vezhlys%gmail.com@localhost>]

FW: forgot to include current-users

---------- Forwarded message ---------
From: Andrius V <vezhlys%gmail.com@localhost>
Date: Sun, Jul 19, 2020 at 2:01 PM
Subject: Re: Unfinished unichrome driver
To: Paul Goyette <paul%whooppee.com@localhost>


Regarding removal, I believed that it should be removed because there
were no references to them in the GENERIC configuration contrary to
GENERIC i386. However, I just checked that padlock driver also existed
(just was commented out, since it was breaking the build). So, I
guess, you are right. I guess I will just submit PR for the crash
then. Thanks.

On Thu, Jul 16, 2020, 05:40 Paul Goyette <paul%whooppee.com@localhost> wrote:
>
> BTW, we should _not_ remove things from the ALL configs.  The ALL is
> supposed to contain "just about everything".  ALL is _never_ guaranteed
> to work, or even reliably build!  :)
>
> On Wed, 15 Jul 2020, maya%NetBSD.org@localhost wrote:
>
> > On Wed, Jul 15, 2020 at 09:18:09PM +0300, Andrius V wrote:
> >> Hi,
> >>
> >> Since my VIA based hardware wasn't attaching a unichrome driver, I decided
> >> to take a look at it. After investigation, I found out that the driver had
> >> been mainly unfinished:
> >> * It matches only one unichrome graphics ID from (CN700 and related
> >> chipsets) and have some hard coded values referencing it here and there
> >> (also, erratically driver refers to graphics from non existent CN900
> >> chipset in few places, including pcidevs, likely CN700 was meant).
> >> * The code itself has definitions for some other unichrome graphics from
> >> CN400, CLE266 (and related) chipsets but not the newer ones
> >> (VX800/VX855/VX900).
> >> * Not included in amd64 ports, similarly to some other VIA specific
> >> hardware drivers.
> >> * It is mentioned in amd64 ALL configuration but without wsdisplay* at
> >> unichromefb?. Likely leftover from i386 and should be removed for now, same
> >> as viadrmums (which causes system to crash in amd64, at least on VX800/900).
> >> * Driver was made compatible with the legacy viadrm driver but it doesn't
> >> seem to work with viadrmums. My system crashed spectacularly once both
> >> enabled.
> >>
> >> It successfully attached and booted with higher resolution for me on CN400
> >> unichrome graphics, once I added its ID without any other modifications.
> >> So, I believe, adding support for all unichrome drivers should not be too
> >> hard. Not sure why it was abandoned and what was unfinished though.
> >>
> >> So out of that I am planning to create PRs unless someone can look at those:
> >> * Add support for all unichrome graphics (possibly can take a look at
> >> this)...
> >> * Make it compatible with viadrmums as it was with viadrm, if that possible.
> >>
> >> Besides that I believe tha viadrmums and unichromefb should be removed from
> >> amd64 ALL kernel configuration, at least for now. And CN900 should be
> >> renamed to CN700 in all places.
> >>
> >> Regards,
> >> Andrius V
> >
> > There's someone working on drm*kms* drivers for VIA graphics hardware
> > for Linux, and also the X driver. It's a good direction to look for
> > anyone that is interested.
> >
> >
> > !DSPAM:5f0fc1f8262394047222629!
> >
> >
>
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