>  > If the QH memory were truly "coherent", that patch could never
>  > matter.  Someone who knows that CPU better should probably
>  > answer more detailed questions.  For example, I'd think that
>  > using uncached mappings for that memory should ensure that the
>  > accesses are "coherent" enough.
>  >
> 
> IMO, depending of the CPU/NorthBridge, the platfrom can or can't support
> partial write to a cache-line if the CPU as a modified cache line.

Do you mean that the host controller is writing an entire cache line's worth of
data (wiping out the software part of the QH), but in a cache coherent way?
i.e. cache coherency has nothing to do with whether DMA writes part or
all of a cache-line at a time?  What gets written after the hardware part of the
QH by the way?  Some random junk from the host-controller's memory?

Thanks a lot,

Duncan.


-------------------------------------------------------
This SF.Net email is sponsored by The 2004 JavaOne(SM) Conference
Learn from the experts at JavaOne(SM), Sun's Worldwide Java Developer
Conference, June 28 - July 1 at the Moscone Center in San Francisco, CA
REGISTER AND SAVE! http://java.sun.com/javaone/sf Priority Code NWMGYKND
_______________________________________________
[EMAIL PROTECTED]
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-devel

Reply via email to