On Friday 15 August 2008, Vernon Sauder wrote: > >I think the "1" and "15" above correspond to threshold register values > >of "0" and "14"; that is the above numbers are the number of words in > >the FIFO that trigger the interrupt/service request. > > All this still leaves me slightly confused. (And I didn't even touch the > dma_burst_size member yet.) I assume that the correct value for all of > these settings must be determined empirically, not just theoretically.
I think you're probably right, although I'd say "optimum" not "correct". Incorrect values should be rejected (or at least ignored) by the driver. > How can I tell what the correct or optimum values are? Do I just use a > performance test on the Flash chip or MMC device? Or can I look at the > logic analyzer output and see what they should be? Or is there a debug > printk that needs to be enabled? I think the idea was that since the PXA hardware manuals don't offer suggestions, this was a "punt it all to the board maintainer" kind of solution. - dave ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ spi-devel-general mailing list spi-devel-general@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/spi-devel-general
