> >
> > Take a look at linux/Documentation/DMA-mapping.txt:
> >
> > > Dynamic DMA mapping
> > > ===================
> > >
> > > David S. Miller <davem@xxxxxxxxxx>
> > > Richard Henderson <rth@xxxxxxxxxx>
> > > Jakub Jelinek <jakub@xxxxxxxxxx>
> >
> > This text documents an API which we now need to examine if suitable for
> > SNx.
> >
> > Kanoj, re our phone discussion - it says:
> >
> > > Drivers converted fully to this interface should not use virt_to_bus any
> > > longer, nor should they use bus_to_virt.
> >
> > Ralf
> >
>
> Leo, looks like other people are starting to get worried about the dma
> and pio issues too. After talking to Ralf, it is clear that some of us
> have to understand how irix handled this, issues involved in the sn0/sn1
> platforms, and then get in touch with David and Jakub ... fast.
> We probably want to reach consensus internally about the general
> structure of the apis first though. Its time to start looking at the
> old papers people put up on bablyon regarding io apis in irix ....
This is a good thing really, even if it doesn't go fully our way
I'm guessing (w/o having seen the document yet) that it will be a
lot easier as a starting point than virt_to_bus/bus_to_virt and
should give us much better driver code capture than we could
otherwise hope for.
>
> The sad truth is, we have to keep supporting older drivers which do
> not follow the apis ...
>
Sure, but we were expecting that anyway.
- leo
> Kanoj
>
Leo Dagum SGI Mountain View, CA 94043 (650-933-2179)
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