Re: [Sm5xx-devel] SM501 framebuffer driver

[Andrey Volkov <avolkov@varma-el.com>]

Hi Paul,

Paul Mundt wrote:
> On Fri, Oct 06, 2006 at 07:25:54PM +0200, Clemens Koller wrote:
>> Great! Where shall we collect the code?
>> I have some 
>>
>> - a working fb driver kernel module
>> 	(I did lots of code cleanup, but still needs a lot)
>>
> There's at least half a dozen of these floating around, with some
> disagreement on the actual implementation. We had one in the old SH tree
> that specifically registered a different framebuffer device for each
> plane, which we had some code in DirectFB and mplayer for making use of
> for overlays and so on.
IMHO, its very awkward implementation for real world application,
especially since, as ex, alpha/video planes is coupled with panel plane
but not with CRT plane. We currently try use sm501 as two fb (crt/panel)
devices.

> 
> There's also another framebuffer driver for this in the Linux/MIPS tree
> that's reasonably clean and might make a better starting point. The main
> issue is supporting both PCI and platform device handling from the same
> driver, since there seem to be just as many in both configurations
> floating around.
> 
PCI and MMIO modes of SM501 is mutually exclusive, so it should be
selected at configure time (as I already does, check my implementation
in svn).

>> - kernel code for an functional complete(?) SM501 implementation for
>> 	an RTS7751R2D Renesas SH-4 Board running Linux.
>>
> It's largely complete, yes, but most of the code is fairly messy, or
> against outdated APIs. It might make a good reference point, but little
> else. The OHCI and i2c drivers are probably the "cleanest" out of these,
> though I haven't gotten around to tidying them up and merging them in to
> mainline as of yet. It might be beneficial to get these in to your sm5xx
> tree though, before we end up having even more duplication (it seems
> there already is with i2c..).
> 
> The OHCI thing was a bit of a mess since the DMA requests need to be in
> the 8051 address space via the accessible SRAM there. You can see our
> lame allocator for that in arch/sh/cchips/voyagergx/consistent.c.
> 
>> Oh, I will need to get the AC97 working, too :-/
>> (my hardware is more or less ready to test some software)
>>
> We also have an OSS driver for SM501, but it contains a lot of 8051
> microcode that needs to be shoved in to userspace, and it needs to be
> reworked for ALSA.
> 
> It should be fairly trivial to rework this for the mfd approach and work
> from there, which I'll look at doing if no one beats me to it and I
> finish some more pressing matters first.
Nice, but please, do it vs berlios svn.

P.S. I repeat my invitation, sm5xx svn/maillists is up and ready.

Andrey

-------------------------------------------------------------------------
Using Tomcat but need to do more? Need to support web services, security?
Get stuff done quickly with pre-integrated technology to make your job easier
Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo
http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642