8260 FCC and local bus

Hi all,

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.

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

Thanks,

====================================================================
Sylvain Latulippe, Technical Leader/Low Level Software Designer
Mediatrix Telecom Inc.		Tel: (819) 829-8749 x257
4229 Garlock Street		Fax: (819) 829-5100
Sherbrooke (Quebec)		Web: http://www.mediatrix.com
Canada J1L 2C8			Email: mailto:slatulippe@mediatrix.com
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** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/

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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