Cache coherency question
DaveLiu at freescale.com
Mon Aug 28 13:17:32 EST 2006
> Ah. This must be the problem. I have a few PCI devices, and
> on one of them it looked like snooping was working. I just
> assumed the other device was setup correctly.
Why one is looked like snooping was working, and the other device
> > Also, you can define the CONFIG_NOT_COHERENT_CACHE, then you are
> > assuming The system has not hardware coherency. You need use the
> > software to keep the cache coherency.
> I tried this, and got compiler errors.
What is the file got compiler errors? I notice that the
Did define CONFIG_NOT_COHERENT_CACHE.
> I added some inline assembly dcbi/dcbf (invalidate/flush)
> instructions to the particular code in question, and the
> problems went away. So definitely a cache problem. As I
> said above, defining CONFIG_NOT_COHERENT_CACHE causes
> compiler errors, so I'm going to look into this more. I
> suppose whatever file implements the
> include/linux/dma-mapping.h stuff isn't BSP specific, so its
> probably just not being compiled in? Will look into it.
Somebody said from maillist. The bridge MV64360 seems
having some issue about cache coherent. I don't know if it is really?
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