Re: [PATCH] starfire reads irq before pci_enable_device.

Donald Becker
2001-02-08T22:05:15Z

On Thu, 8 Feb 2001, Jeff Garzik wrote:

> > Well, I decided to bite the bullet and port my zerocopy starfire
> > changes to the official tree, properly ifdef'ed. So here it goes,
>
> I would prefer that the zerocopy changes stay in DaveM's external patch
> until they are ready to be merged. Zerocopy is still changing and being

Good idea -- I expect that there will be significant interface changes
before the zero-copy code stabilizes.

> > + * The ia64 doesn't allow for unaligned loads even of integers being
> > + * misaligned on a 2 byte boundary. Thus always force copying of
> > + * packets as the starfire doesn't allow for misaligned DMAs ;-(
...
> Note that I have not yet sent this patch onto Linus for a reason...
> Here is Don Becker's comment on the subject:

> > Oh, and this is completely bogus.
> > This isn't a fix, it's a hack that covers up the real problem.
> >
> > The align-copy should *never* be required because the alignment differs
> > between DIX and E-II encapsulated packets. The machine shouldn't crash
> > because someone sends you a different encapsulation type!

This is true for a number of drivers -- triggering the copy-align code
might eliminate the misaligned traps on your local network, but it's not
a solution.

I saw the Adaptec people last week at LinuxWorld. The 2.4.0 starfire
has a number of actual bugs that should be fixed RSN:
The consistency check in the Rx code was broken. Did anyone ever try
the driver after the changes? The test triggers with every received
packet. The easiest patch is to just get rid the consistency checks
inside "#ifndef final_version".

The region resource was not released, requiring a reboot between each
driver test. Trivial fix.

The MII read code is no longer reliable. I spent twenty minutes at
the show, but couldn't figure out the problem. I haven't been able
reproduce the problem locally with my 2.2 code and someone older
hardware.

Donald Becker becker@scyld.com
Scyld Computing Corporation http://www.scyld.com
410 Severn Ave. Suite 210 Second Generation Beowulf Clusters
Annapolis MD 21403 410-990-9993