RE: SCSI QLA not working on latest *-mm SN2

Andrew Vasquez
2004-09-17T22:59:32Z

On Thursday, September 16, 2004 4:14 PM, Jeremy Higdon wrote:
> On Thu, Sep 16, 2004 at 01:56:50PM -0700, Andrew Vasquez wrote:
> >
> > Interesting, the only changes in reset_chip() are for PCI posting
> > issues. Relevant diff attached.
> >
>
> Are all of those reads really necessary? Generally the only reason
> for doing a read to flush a posted write is for timing issues (in
> which the read may not be good enough, according to a thread I saw
> from Grant Grundler), or to enforce ordering before releasing a lock
> (sleeping or spinning).
>

The reads are there to ensure ordering of the writes at each stage of
the reset (in qla_init.c) and fw dumps (qla_dbg.c). After speaking
with the hardware and firmware folks, the readw() after the
soft-reset in qla_init.c was probably what triggered the MCA. Seems
we will have to settle for some sort of udelay() as what was done in
reset_chip().

> Have you run into platforms in which two I/O writes from one CPU are
> retired out of order?
>

Again, only for completeness.

Regards,
Andrew Vasquez