On Tue, Jan 20, 2004 at 11:10:29AM +0100, Dimitri Torfs wrote: > Hi, > > what are the requirements on the transfer_buffer field of an urb in > case URB_NO_TRANSFER_DMA_MAP is not set ? Since this value is passed > to dma_map_single() I would expect it to be cache-linesize aligned. > I suppose that is (a.o.) what meant in usb.h when it says > "it should be suitable for DMA", right ?
Yes. > I ask this question because there are places in the code where this > requirement clearly is not met. Is it because people are not aware > of this requirement or because they expect that cache-effects will > not come into play ... (or because they don't run on a > cache-incoherent platform) ? Where are those places? And yes, it's probably because we all run on systems where this is not noticed :) thanks, greg k-h ------------------------------------------------------- The SF.Net email is sponsored by EclipseCon 2004 Premiere Conference on Open Tools Development and Integration See the breadth of Eclipse activity. February 3-5 in Anaheim, CA. http://www.eclipsecon.org/osdn _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
