31st address line sometimes not used on EHCI/UHCI/OHCI

Hans Petter Selasky hselasky at c2i.net
Sun May 27 20:35:59 UTC 2007


Hi,

I've got some reports back that some USB host controllers do not support 
transferring memory from a location higher than 2GB.

What should we do about this?

Should we limit all USB DMA allocations to the lower 2GB of the memory?

--HPS


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