Re: [PATCH] IBM Lanstreamer bugfixes (round 3)

Jeff Garzik
2002-03-04T17:04:46Z

Kent Yoder wrote:
>
> Jeff,
>
> I have a feeling you're talking about this section:
>
> > pci_write_config_byte (pdev, PCI_CACHE_LINE_SIZE, cls);
> > pci_read_config_word (pdev, PCI_COMMAND, &pcr);
> >
> > /* Turn off Fast B2B enable */
> > pcr &= ~PCI_COMMAND_FAST_BACK;
> > /* Turn on SERR# enable and others */
> > pcr |= (PCI_COMMAND_SERR | PCI_COMMAND_INVALIDATE | PCI_COMMAND_PARITY |
> > PCI_COMMAND_IO | PCI_COMMAND_MEMORY);
> >
> > pci_write_config_word (pdev, PCI_COMMAND, pcr);
> > pci_read_config_word (pdev, PCI_COMMAND, &pcr);
>
> Basically, this section exists from a time when I had no idea why the
> card was behaving badly, so I was trying everything :-).
>
> So, after revisiting them, I see that setting cache line size to 0 and
> then using memory write and invalidate doesn't make any sense. I'm thinking
> both can just be dropped, since I haven't seen any change in performance on
> the machines I've made netperf runs with (a constant 14.7 Mb/s) after
> changing these.

I agree to the first part :)

Set cache line size just like drivers/net/acenic.c does, and enable
memory-write-invalidate...

Jeff

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Jeff Garzik |
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