> On 21 Feb 2017, at 19:00, Maxime Ripard <maxime.rip...@free-electrons.com> > wrote: > > On Fri, Feb 17, 2017 at 06:22:45PM +0100, Philipp Tomsich wrote: >> Throughput tests have shown the sunxi_mmc driver to take over 10s to >> read 10MB from a fast eMMC device due to excessive delays in polling >> loops. >> >> This commit restructures the main polling loops to use get_timer(...) >> to determine whether a (millisecond) timeout has expired. We choose >> not to use the wait_bit function, as we don't need interruptability >> with ctrl-c and have at least one case where two bits (one for an >> error condition and another one for completion) need to be read and >> using wait_bit would have not added to the clarity. >> >> The observed speedup in testing on a A31 is greater than 10x (e.g. a >> 10MB write decreases from 9.302s to 0.884s). >> >> X-Affected-platforms: A31-uQ7, A80-Q7, A64-uQ7 >> Signed-off-by: Philipp Tomsich <philipp.toms...@theobroma-systems.com> > > Awesome, I was about to start looking into the poor performances we > had, but you beat me to it. > > Do you know if the same changes can apply to the Linux MMC driver?
We’ve never seen performance problems on Linux and benchmarked at up to ~50MByte/s on the A31-uQ7. You might want to follow up off-list with Klaus on this, though... Cheers, Philipp. _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot