[vortex] 3c905CX things

[Donald Becker]

On Mon, 1 Jan 2001, Andrew Morton wrote:

> I've finally had a sane report back from a 905CX owner.  It
> takes 32 milliseconds for the initial RxReset to complete.

You've found out that it does sometime take a long time to get accurate
reports on new hardware.  It is usually only very new users that have the
latest hardware.

32 milliseconds likely means that some hardware designer just put in a bogus
delay rather than do it correctly, just as some software people put in
patch-up code rather than fixing a bug source.

> Questions:
> 1: Why is vp->phys[] a two-char array?  The driver never uses anything
>    apart from phys[0].

It was to support cards with multiple transceivers, or an external MII
connector.  To my knowledge, 3Com hasn't produced any such card.  An HomePNA
card would be a likely product to use a second transceiver, but 3Com is just
putting their name on Broadcom hardware.

> 2: I'm including this code:
>         pci_read_config_byte(pdev, PCI_LATENCY_TIMER, &pci_latency);
>         if (pci_latency < new_latency) {
...
>                 pci_write_config_byte(pdev, PCI_LATENCY_TIMER, new_latency);
> 
> But this is currently done for all PCI devices.  Shouldn't it
> only be done for IS_VORTEX devices?

Yes, this bug only exists on 3c590 (IS_VORTEX) chips.

Donald Becker				becker@scyld.com
Scyld Computing Corporation		http://www.scyld.com
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