Re: [Gnewsense-dev] [debian-yeeloong-project] [loongson-dev] Graphic acceleration on Yeeloong anyone?

[Mart Raudsepp]

On N, 1970-01-01 at 00:00 +0000, Roman Mamedov wrote:
> 
> As for Gentoo, I don't know, is there even a way to use it on the
> Yeeloong
> without having to personally compile every singly package you install?
> Because that's certainly not what I would want to do on a slow
> netbook. 

As Matt already told in your quoted text (I don't have his original mail
in my box yet):

> Gentoo has n32/multilib
> stage4s with pre-built Xfce available on our mirrors in
> /experimental/mips/desktop-loongson2f/


So you can have a fully-fledged XFCE4 desktop image as a starting point
and add on what you need, and gradually upgrade things to newer versions
when you can afford some CPU usage. It's not THAT slow really,
definitely not as slow as the 166MHz computers I started out with on
Gentoo :)

Also, pixman and the likes is where it becomes interesting for
performance. Matt's optimizations for using the loongson multimedia
instruction set on loongson2f (which is very similar to MMX) for greater
software graphics performance, etc.

Now if someone would figure out any graphics driver caused slowness and
fix that, it'd be nice. It could probably do a lot better easily, but
with XAA performance regressed in xserver and by now outright removed,
it's probably a very sad story with EXA, while it could be made to at
least not be slower than pure software which I suspect it is. You
essentially WANT everything to be pure software on that "GPU" without
EXA or XAA trying to accelerate, but not just straight NoAccel option as
you'd then lose Xvideo too.

Someone maybe could test how it is these days for 2D graphics
performance with cairo-perf benchmarks suite with NoAccel and without
it.

But the bottom-line is - for graphics performance on yeeloong with its
very old awful SMI 2D-silicon without alpha compsiting graphics you can
really only accelerate with pixman in software, and make sure graphics
driver doesn't decelerate by moving pixmaps around a lot for the very
few things that can be accelerated, as that highly offsets any potential
gains.

Unfortunately while my expertise could allow to see what can be improved
and do so, I haven't had any unpaid free hobby time for that.
NoAccel comparisons could be interesting, to see if driver gets in the
way.


Best,
Mart Raudsepp