> > > New IO FPGA implementation for Versatile Express boards contain > > > MMCI (PL180) cell with FIFO extended to 128 words (512 bytes). > > > > > > Signed-off-by: Pawel Moll <pawel.moll@xxxxxxx> > > > > Tested-by: Matt Waddel <matt.waddel@xxxxxxxxxx> > > > > This patch improves MMC performance on my vexpress system. Also > > fixes "mmcblk0: error -5 transferring data" errors. > > You should use the patch I sent to do dynamic clocking if you're > concerned about performance. That patch improves performance by > a factor of 8 compared to anything possible by increasing the FIFO > depth. > > I am very much of the opinion that deepening the FIFOs is just a > sticky plaster over the problem - and I said as much when it was > first proposed, pointing out that there's other better solutions. # cat /sys/devices/mb\:mmci/id 01041180 # cat /sys/module/mmci/parameters/fmax 12000000 # dd if=/dev/mmcblk0 of=/dev/null bs=128k count=100 100+0 records in 100+0 records out 13107200 bytes (13 MB) copied, 9.04218 s, 1.4 MB/s Of course without the proper error handling, as introduced by your patch, one will face the same problems with interrupt latency as previously. But the peak performance seems to noticeably better... Regards PaweÅ PS. The FPGA with extended MMCI FIFO will be available on the next VE CD update, which is going to be released next month. -- 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
