Hello,
On Wed, 21 Mar 2018 12:18:58 +0100 Maxime Ripard maxime.ripard@bootlin.com wrote:
From: Philipp Tomsich philipp.tomsich@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).
Signed-off-by: Philipp Tomsich philipp.tomsich@theobroma-systems.com Signed-off-by: Maxime Ripard maxime.ripard@bootlin.com
Tested-by: Mylène Josserand mylene.josserand@bootlin.com
Thanks,