tree d1910e5d1867242c5e0e7b12a017850b46dc4a61
parent 152f05c783438b57bb42e8171aa871c49ae5b2d5
author Dong Aisheng <aisheng.dong@nxp.com> 1468309577 +0800
committer Ulf Hansson <ulf.hansson@linaro.org> 1469435695 +0200

mmc: sdhci: add standard hw auto retuning support

If HW supports SDHCI_TUNING_MODE_3 which is auto retuning, we won't
retune during runtime suspend and resume, instead we use Re-tuning
Request signaled via SDHCI_INT_RETUNE interrupt to do retuning and
hw auto retuning during data transfer to guarantee the signal sample
window correction.

This can avoid a mass of repeatedly retuning during small file system
data access and improve the performance.

Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>