From mboxrd@z Thu Jan 1 00:00:00 1970 From: hkallweit1@gmail.com (Heiner Kallweit) Date: Sun, 10 Sep 2017 18:20:05 +0200 Subject: Problems after recent changes to meson-gx-mmc driver In-Reply-To: <1505056105.24771.53.camel@baylibre.com> References: <1504965959.24771.42.camel@baylibre.com> <763e9339-92a4-c2c4-bbe6-ee9f831148ec@gmail.com> <6a4baa6c-e5f0-fe51-f958-adde9e39b4c9@gmail.com> <1505056105.24771.53.camel@baylibre.com> Message-ID: To: linus-amlogic@lists.infradead.org List-Id: linus-amlogic.lists.infradead.org Am 10.09.2017 um 17:08 schrieb Jerome Brunet: > On Sat, 2017-09-09 at 22:20 +0200, Heiner Kallweit wrote: >> I checked further and setting the tx clock phase back to 0 fixes the issue for >> me. >> ("mmc: meson-gx: change default tx phase" changes it from 0 to 270.) >> But as you write 0 seems to break certain other systems. > > That was my second guess ... > > As I mentioned in the commit message, 270 is working fine for the setups I have > tested but I always wondered if that would be the case for every possible > setups/boards/modes. > > Would you mind testing 90 and 180 as well with your setup ? I'll make another > pass on the different setups I have access to. Please stick to hs200 and drop > hs400 for this test. I'm still unsure if doubling the clock after doing the > tuning may affect the phase tuning ... lets keep that out of the way for now. > I tested the other tx clock settings with HS200/200MHz. 0: No errors 90: 6 CRC errors, otherwise system works normal. 180: Lots of CRC errors, but system still works. 270: So many errors that root file system gets corrupted and is mounted r/o. Seems like we won't find a tx clock phase working on all systems. So maybe the tuning needs to be extended to check all tx / rx clock phase combinations. IIRC I went with a fixed tx clock phase because other combinations of tx / rx clock phase selected by an experimental tuning algorithm worked fine when tuning but produced errors later.