On Tue, Oct 30 2012, Chris Ball wrote: > Hi, > > On Mon, Oct 22 2012, Kyoungil Kim wrote: > > We used only single sg entry for SDIO transfer. > > This chagne is to use multiple sg entry. > > In case of dwmci, it support only up to 4KB size per single sg entry. > > So if we want to transfer more than 4KB, we should send more than 1 command. > > This makes performance degradation for large data transfer. > > > > Signed-off-by: Kyoungil Kim <ki0351.kim@xxxxxxxxxxx> > > Can you share the before/after benchmark on your controller, please? When we test before apply this patch, it takes around 335 us for 5K(5120) bytes transfer with dwmci controller. But when we test after apply this patch, it takes 242 us for 5K bytes. So this patch makes around 38% performance improvement for 5K bytes transfer. If the transfer size is bigger, then the performance improvement ratio will be increased. Thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
