> There is a limitation on the DMA range. Current device can't handle > whole ZONE_DMA range, so there is a "backup" mechanism which copies the > entire packet if the mapping was failed or if the packet's mapped > address is out of this range, this is done on both rx and tx directions.
If you use the DMA API correct, it should hide all this, and do the bounce buffers for you. But i'm no DMA expert... Andrew