cache control functions

Matt Porter porter at cox.net
Thu Mar 13 06:22:40 EST 2003


On Wed, Mar 12, 2003 at 01:02:14PM -0600, Eric Seppanen wrote:
>
> I'm writing a driver module, for a pci device that lives in a 405GPr
> based system.  I notice that the 405 doesn't seem to have a consistent
> cache after the pci device busmasters a bunch of data into SDRAM (or
> before it pulls data out), so I think the thing I'm supposed to do is
> call (depending on direction) one of these:

<snip>

> Is this intentional or an oversight?  I can't see how I can write a
> driver for a busmaster device (that will work on a 405) without them.

Use the standard API described in Documentation/DMA-mapping.txt
You will find that there are PPC-specific (sort of, ARM has the same
names) versions of generic PCI DMA API defined in include/asm-ppc/io.h
Those can be used on on-chip or other non-PCI type device (stuff on
the EBC for 4xx).

Regards,
--
Matt Porter
porter at cox.net
This is Linux Country. On a quiet night, you can hear Windows reboot.

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