New API for non cache coherent ppc cpu's

Dan Malek dan at
Sat Nov 24 03:08:29 EST 2001

Paul Mackerras wrote:

> To go with pci_map_page and pci_unmap_page.  These give you the
> ability to do DMA to highmem pages without using bounce buffers.

IIRC, there was a virt_to_bus in the code at one time, making it
unusable for highmem pages, which is why I couldn't understand
the appearance of the function.

> My preference would be to make the one set of functions work
> everywhere.

Mine, too.  I just wish this was a common concept across a variety
of our I/O interfaces.

> ....  OTOH these non-PCI devices you're talking about are
> presumably very specific to PPC embedded chips so maybe it doesn't
> matter so much.

That is always a challenge with the embedded parts.  It is often
very convenient to make the (promper, IMHO) assumption this software
isn't going to be used outside of these parts.


	-- Dan

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