From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jerome Brunet Subject: Re: eMMC tuning issue on Odroid C2 and a possible solution Date: Thu, 12 Oct 2017 22:05:45 +0200 Message-ID: <1507838745.16356.270.camel@baylibre.com> References: <1507821759.16356.225.camel@baylibre.com> <1507836874.16356.258.camel@baylibre.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-wm0-f51.google.com ([74.125.82.51]:45452 "EHLO mail-wm0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753101AbdJLUFs (ORCPT ); Thu, 12 Oct 2017 16:05:48 -0400 Received: by mail-wm0-f51.google.com with SMTP id q124so16126124wmb.0 for ; Thu, 12 Oct 2017 13:05:48 -0700 (PDT) In-Reply-To: Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Heiner Kallweit Cc: "linux-mmc@vger.kernel.org" , "open list:ARM/Amlogic Meson..." , Kevin Hilman On Thu, 2017-10-12 at 21:49 +0200, Heiner Kallweit wrote: > > The result of the tuning does not depends on starting point, so I don't > > really > > understand how it would significantly change things. > > > > I think it depends on the tx phase starting point. > If the result of the tuning is not independent of the starting, instead of just telling me, it is fairly easy for you to give actual result, like I asked you: > > Ok, starting from Rx:0 Tx:270 then tuning gives you Tx:300 Rx:90 > > And what different did it gives you starting Rx:0/Tx:0 ? And if the result are indeed vastly different, let's debug and get a real explanation. > Tuning does: > rx phase tuning > tx phase tuning > rx phase tuning > > Result of each step depends on result of previous step. Again, we don't agree. > So also the initial > rx phase tuning result depends on the starting point of tx phase. The first Rx tuning is there only to get a sane starting point for the tx tuning ,as explained in the code. This is the reason why is not done when re-tuning.