[PATCH RFC 2/8] DRM: Armada: Add Armada DRM driver

[Russell King - ARM Linux]

On Tue, Jun 11, 2013 at 09:48:57AM +1000, Dave Airlie wrote:
> On Tue, Jun 11, 2013 at 9:36 AM, Russell King - ARM Linux
> <linux at arm.linux.org.uk> wrote:
> > On Tue, Jun 11, 2013 at 09:24:16AM +1000, Dave Airlie wrote:
> >> I'd like to see all the ARM based drivers based on CMA if it can meet
> >> their requirements
> >> and using close to standard GEM/dma-buf interfaces. Otherwise it'll be
> >> come an unmaintainable
> >> nightmare for everyone, but mostly for me.
> >
> > I am *not* using the CMA layer - that layer is just plain broken in
> > DRM.  It forces every single gem object to be a CMA allocated object,
> > which means I can't have cacheable pixmaps in X.  And that makes X
> > suck.
> >
> > Okay, I'm pulling this and I'm going to keep it in my private cubox
> > tree; I'm not persuing pushing this driver or any other Armada 510
> > driver into mainline anymore.  It's just too much fscking hastle
> > dealing with people who don't like various stuff.
> >
> > I've done my best to clean a lot of the crap up, and the problem is
> > that no matter how much I clean up, it remains unacceptable.  Only
> > the 100% perfect solution seems to be acceptable.  That is
> > unacceptable given that this stuff has already consumed something
> > like 8 months solid of my time.
> 
> Russell, aren't you a kernel maintainer, because for fuck sake get real.
> 
> I'm not merging bullshit into my tree that has a completely broken API that
> has to be maintained for ever. You of all people should understand we
> don't break Linux
> userspace APIs, and adding a phys addr one is wrong, wrong, wrong, its not
> cleanups, its just broken, and I'll never merge it.

As I say, I'm no longer interested in pushing this into mainline.  I've
said my piece above, and I'm not changing that.  I'm not spending years
trying to sort this stuff out, by which time the platforms using it will
be long since obsolete.  The "8 months" is not an exaggeration.  That's
the time taken to sort out the kernel side, the libdrm stuff, the
X server driver, and get video decode working on these platforms with
vlc.

It works for me, and that's really at this point all I care about.

And yes, I'm a kernel maintainer.  A FUCKING busy one right now at that.
I haven't stopped working since 9am today yet, and it's now 1am.  Do the
maths.  I really wish I had some time to myself now to think about some
of these bigger issues which this has brought up, but I don't.

And no, I *never* said that adding a phys address was a cleanup.

Sheesh why don't you read my emails properly.  Another reason why I
won't be continuing this discussion much further.

I said that _this_ amount of effort is a result of doing *LOTS* of
cleanups.  A DRM driver for this hardware *didn't* exist until I wrote
it.  There was a fbdev driver before, which was passed phys addresses
there for the overlay, and passed phys addresses back out after the
overlay frame has been replaced.