CPU Cache and busdma usage in USB

[Stanislav Sedov]

On Mon, 29 Jun 2009 13:37:41 +0200
Hans Petter Selasky <hselasky at c2i.net> mentioned:

> USB is currently _updating_ (!!) the PAGE offset part of "vaddr". If 
> cpu_dcache_inv_range() is called with an address not starting at the cache 
> line what will the cpu_dcache_inv_range() do? Will it skip to the next cache 
> line? Or will it completely skip the whole cache sync operation?!

Currently, the address passed to cpu_dcache_inv_range will be rounded up
to the cache line boundary and the whole line will be invalidated if the
range requested is smaller than 16KiB.  Otherwise, the whole cache will
be invalidated.

-- 
Stanislav Sedov
ST4096-RIPE
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