Re: The CVPPC on board SCSI driver.

[Michel <mi...@da...>]

On Wed, 2002-07-24 at 14:27, Rene Brothuhn wrote:
> On 2002.07.24 12:33 Ken Tyler wrote:
> >=20
> > I came across a pait of 4.3 Gig UW SCSI drives at a give away price the
> > other day.  I thought I might grab them and have ago.
> >=20
> > What's the status of the driver ?
> >=20
> > I know it doesn't work and that Fred H (possibly someone else too ) hav=
e
> > tried modding existing drivers.
> >=20
> > Which driver almost worked (can't remember the details - some sort of
> > cache coherency problem ?).
>=20
>=20
> Hi, Ken!
>=20
> I'm working on the driver. But I have to give up my work for several=20
> month, due to lack of time. But for some weeks, I got a little time back=20
> and contiune my work on the driver.
>=20
> So, for now it seems that all the cache coherency problems are solved. An=
d=20
> the communication between the lowlevel and midlevel SCSI driver thru DMA=20
> seems working correctly now (which wasn't since i stopped my work). The=20
> driver detects the devices connected to the SCSI bus and prints out the=20
> names, revision numbers and so on.

Great to hear you're making progress! Can you please commit what you
have, so others can look at it?

> After that, when the driver tries to reselect a device (for reading out=20
> the capacity...), I got an illigal instruction exception from the SCRIPTS=
.=20
> But there is no illegal instruction. The documentation of the 53c770 says=
,=20
> that illigal instruction exception also occur on some illegal phases on=20
> the SCSI bus. I don't know much about SCSI bus arbitration, but I'm=20
> learning...

I don't really know anything about this, but if the CPU hits an illegal
instruction, there could still be coherency issues?


--=20
Earthling Michel D=E4nzer (MrCooper)/ Debian GNU/Linux (powerpc) developer
XFree86 and DRI project member   /  CS student, Free Software enthusiast