Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030660AbaDBWUp (ORCPT ); Wed, 2 Apr 2014 18:20:45 -0400 Received: from mail-pd0-f175.google.com ([209.85.192.175]:44584 "EHLO mail-pd0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933158AbaDBWUm (ORCPT ); Wed, 2 Apr 2014 18:20:42 -0400 MIME-Version: 1.0 In-Reply-To: <533C8B49.8080704@ahsoftware.de> References: <1396396559-6971-1-git-send-email-holler@ahsoftware.de> <533BD3CD.1010905@ahsoftware.de> <533C721E.1080004@gmail.com> <533C8B49.8080704@ahsoftware.de> From: Florian Fainelli Date: Wed, 2 Apr 2014 15:20:00 -0700 Message-ID: Subject: Re: [PATCH regression] net: phy: fix initialization (config_init) for Marvel 88E1116R PHYs To: Alexander Holler Cc: Sebastian Hesselbarth , "linux-kernel@vger.kernel.org" , netdev , Michal Simek , stable Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2014-04-02 15:12 GMT-07:00 Alexander Holler : > Am 02.04.2014 22:25, schrieb Sebastian Hesselbarth: >> On 04/02/2014 09:01 PM, Florian Fainelli wrote: >>> 2014-04-02 2:09 GMT-07:00 Alexander Holler : >>>> Am 02.04.2014 02:57, schrieb Florian Fainelli: >>>>> 2014-04-01 16:55 GMT-07:00 Alexander Holler : >>>>>> Commit 7cd1463664c2a15721ff4ccfb61d4d970815cb3d (introduced with 3.14) >>>>>> changed the initialization of the mv643xx_eth driver to use phy_init_hw() >>>>>> to reset the PHY. Unfortunately the initialization for the 88E1116R PHY >>>>>> was broken such, that it used mdelay() instead of really waiting for a >>>>>> reset to finish. >>> >>> Can you resubmit with the following information: >>> >>> - you specify the commit that introduce the problem in parenthesis, >>> e.g: deadbeef ("dead: beef: cafe babe") >>> - put this dmesg snippet in your log message to clearly illustrate >>> what is happening >>> - clarify that the PHY needs to be polled in a comment in >>> m88e1116r_config_init() >>> >>> Meanwhile, it would be good if someone with access to this particular >>> PHY datasheet could look for known erratas, problems, non-standard >>> compliant behavior .... >> >> Alexander, >> >> I tried todays linux/master on Seagate Dockstar with Marvell 88E1116R >> (0x01410e40) and cannot reproduce any regression. I tried booting from >> tftp and usb, I also rebooted twice to see if there are any side >> effects - nothing - ethernet always comes up as expected. >> >> I am curious, how you determined above commit to be the cause of the >> regression you are seeing. Can you bisect, if you didn't already? > > There was no bisecting necessary. I've just looked at what changed in > mv643xx_eth since 3.13 and the first commit I've reverted was already a > hit. Reading a bit source revealed the differences between the old reset > and the newly used one and ended up with my patch (first try) and was a > hit too. > > Actually I assumed the reset needs longer than the 500ms, but as the > printks revealed, the reset is much faster. > So the problem seems to be the much increased time (1s) the newly used > reset function idles in mdelay. > > But I think I have found the real reason. and the change of the reset > just increased the chance the problem is hit (here with 100% success or > fail rate however you want to name it). > > Just give me a day or two to find the time to verify my assumption (I > don't want to speculate) and maybe find a real fix for the problem. Of > course, I still like my patch because it greatly decreases the time > necessary for a reset (and the chance to hit the problem). Why so mysterious, care to share your assumption? -- Florian -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/