Re: Pegasos and viaide interrupts

Frank Wille wrote:
> Matt Sealey wrote:
> 
>>> Digging a bit deeper in the viaide driver showed me that it depends on
>>> the
>>> PCI_INTERFACE register, whether we are in native or compatible mode.
>>> Looking
>>> at this register showed me the value 0x8f, which means native mode for
>>> both
>>> channels (bit 0 and 2).
>>> [...]
>> I'm afraid you will have to taint yourself with GPL code and look at the
>> Pegasos platform fix in the latest kernels for the Via IDE stuff.
> 
> I have downloaded the latest Linux sources a few days ago, and it looked to
> me as if they just hardcoded interrupt 14 and 15 for Pegasos, and driving it
> in compatible (legacy) mode. MorphOS is doing the same, BTW.

I should clarify; it's not mainlined yet but it is floating around and
should be submitted for .24 or .25.

Prepare to be tainted by the GPL:

https://bugzilla.redhat.com/attachment.cgi?id=167747

>> You need
>> to do a little tweak or two to get it to work in native mode properly.
> 
> So it is meant to work in native mode? That's interesting! Any pointer to the
> information we are missing?

It does work in native mode, but it's not set up that way.

With the small patch above, the class-code is modified such that it reports
that it's in native mode. I'm not even sure if this is right anymore.. every
time I look at it I wonder what the hell is wrong with Via IDE chips and
all the discussions I had with Jeff, Alan and Tejun about it..

The patch above, to me, can't work since the interrupt 15 is taken out of
the properties. The comment, therefore, is a load of bullshit :)

Ah I dunno. Who knows anymore. At some point someone reworked a patch I
was working on, and it allowed libata pata_via to work on Pegasos without
too much hassle.

>> Remember the OF device tree is broken and reports the wrong interrupts
> 
> Hm. My firmware (1.2) does not report any interrupts at all.

Linux also re-reads the PCI interrupt line from each PCI device when it
boots (firmware can not be trusted it seems :)

-- 
Matt Sealey <[email protected]>
Genesi, Manager, Developer Relations