On 04/26/2016 05:03 PM, Enric Balletbo i Serra wrote: > Hi, > > I introduced the cover letter to give some background about this. > > I have been investigating a problem related to at least one specific sdcard > when > UHS-I is set. The card is not detected due the tuning phase reports a > failure. Since the problem is only reproduced with a single model of a single > brand of card, it is probably a card firmware issue, but the card works fine > on my laptop.
I think you have analyzed many case..of course..it was successful to switch voltage, right? Maybe this patch too old..so can you remember which specific sdcard is produced? > > The first attempt to fix this was a patch sent by Doug Anderson [1], but Alim > Akhtar found that this produced randomly a hung task on Peach-pi. I can > confirm > that it's easy to reproduce the hung task, either, with cold boots or suspend > to > ram tests. Yep..I have already tested and checked for this. > > I tried to fix both problems (the original issue and the one introduced by the > patch) in different ways, but I ended thinking that this second proposal is > the > most simple that solves both issues. So let's try to fix this by handling the > response CRC error slightly differently when tuning command is happening. > > I tested the patch on both platforms, on exynos and on rockhip. I did lots of > tests and at the moment the patch seems to fix the rockchip issue and don't > hung on exynos. I'll continue testing meanwhile we discuss about it. > > I think the patch, at least, needs the Doug's approval (as he dig into the > issue > before) and the Tested-by Alim. So will be good if you have a slot of time to > look a bit into this. > > Thanks in advance. > Enric > > [1] https://lkml.org/lkml/2015/5/18/495 > > Changelog since v1: > - Fix the issue found by Alim with exynos letting the data transfer > take place only when MMC_SEND_TUNING_BLOCK is issued. > > Doug Anderson (1): > mmc: dw_mmc: Wait for data transfer after response errors. > > drivers/mmc/host/dw_mmc.c | 27 +++++++++++++++++++++++++++ > 1 file changed, 27 insertions(+) >
