On Wed, Apr 4, 2018 at 12:36 PM, Maxime Ripard <maxime.rip...@bootlin.com> wrote: > On Wed, Apr 04, 2018 at 12:13:01PM +0530, Jagan Teki wrote: >> On Wed, Mar 21, 2018 at 4:48 PM, Maxime Ripard >> <maxime.rip...@bootlin.com> wrote: >> > From: Philipp Tomsich <philipp.toms...@theobroma-systems.com> >> > >> > 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). >> >> Fyi: I've seen significant improvement, but not 10x on A64 >> (bananpi-m64) with read >> >> Before this change: >> >> => mmc dev 0 >> switch to partitions #0, OK >> mmc0 is current device >> => fatload mmc 0:1 $kernel_addr_r Image >> reading Image >> 16310784 bytes read in 821 ms (18.9 MiB/s) >> => mmc dev 1 >> switch to partitions #0, OK >> mmc1(part 0) is current device >> => ext4load mmc 1:1 $kernel_addr_r Image >> 16310784 bytes read in 1109 ms (14 MiB/s) >> >> >> After this change: >> >> => mmc dev 0 >> switch to partitions #0, OK >> mmc0 is current device >> => fatload mmc 0:1 $kernel_addr_r Image >> 16310784 bytes read in 784 ms (19.8 MiB/s) >> => mmc dev 1 >> switch to partitions #0, OK >> mmc1(part 0) is current device >> => ext4load mmc 1:1 $kernel_addr_r Image >> 16310784 bytes read in 793 ms (19.6 MiB/s) > > Yeah, the smaller the file is, the bigger the gain is. Since you have > an almost twice bigger file, the gains are probably just noise at that > point and the bottleneck starts to be your MMC.
Acked-by: Jagan Teki <ja...@openedev.com> _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot