Quinn Jensen wrote:
>
> jsun@hermes.mvista.com wrote:
>
> > Quinn Jensen wrote:
> >
> >>>> Is anyone else having trouble with NFS root on
> >>>> the 2.4.0 kernel? It won't come up with the
> >>>> KSEG0 cache on unless I pepper the network driver
> >>>> with flush calls.
> >>>
> >>>
> >>> That's expected for most old network drivers that don't yet use tye
> he
> >>> new PCI DMA API documented in Documentation/DMA-mapping.txt.
> >>>
> >>> What driver is this?
> >>
> >> Both the stock 2.4.0 tulip and eepro100 drivers. The
> >> problem doesn't happen when I go back to 2.3.99pre8.
> >>
> >
> > Did you set rx_copybreak to 1518? I sent patches long time ago to the
> > driver
> > authors for MIPS, but I am not sure they are not there.
>
> Jun,
>
> I have tried that in this case but it didn't help,
> because the receive skb data pointers all point to
> the KSEG0 view of the data anyway.
I looked into similar problems a while back. If I remeber correctly, the data
pointers do point to kseg0. It is up to the driver to do appropriate
dma_cache_invalidate() (or some functions to that effect) at certain places.
What is the CPU? It seems logical to suspect about the dma cache routines.
Jun
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