8260 FCC and local bus

[Allen Curtis]

> I have found some information in the mailing list regarding usage of local
> bus ram for FCC BD's and buffers.  However I haven't found any
> conclusion if
> it's working.

Yes, you can use local RAM for the BD's and buffers. There is a penalty
because you need to move the buffers between local and 60X RAM. I have found
information on the list indicating that you can use IDMA for this purpose.
(search with the keyword "profiling" in embedded)

> Has anyone done it successfully?
> What kind of support does linux provide regarding local bus ram? (Ram
> drive,...)

No real support for local RAM per say. You need to treat it as any other
memory mapped device. Therefore you need to change all _va()/_pa() calls to
ioremap() and iopa().

Note: If you are using rev-A 8260 processors, this helps a lot.


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