From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-out.m-online.net ([212.18.0.10]:34602 "EHLO mail-out.m-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750875AbaFZJuG (ORCPT ); Thu, 26 Jun 2014 05:50:06 -0400 From: Marek Vasut To: Juergen Borleis Subject: Re: [RFC] PCI: pci-imx6: Add delay to workaround kernel hang Date: Thu, 26 Jun 2014 11:50:01 +0200 Cc: Fabio Estevam , Shawn Guo , Bjorn Helgaas , Richard Zhu , "David =?iso-8859-1?q?M=FCller?= (ELSOFT AG)" , Sascha Hauer , "linux-arm-kernel@lists.infradead.org" , "linux-pci@vger.kernel.org" , Tim Harvey , Fabio Estevam References: <1403637507-9424-1-git-send-email-festevam@gmail.com> <201406261117.12542.marex@denx.de> <201406261126.09235.jbe@pengutronix.de> In-Reply-To: <201406261126.09235.jbe@pengutronix.de> MIME-Version: 1.0 Content-Type: Text/Plain; charset="us-ascii" Message-Id: <201406261150.01965.marex@denx.de> Sender: linux-pci-owner@vger.kernel.org List-ID: On Thursday, June 26, 2014 at 11:26:09 AM, Juergen Borleis wrote: > Hi Marek, > > On Thursday 26 June 2014 11:17:12 Marek Vasut wrote: > > On Thursday, June 26, 2014 at 09:32:30 AM, Juergen Borleis wrote: > > > On Thursday 26 June 2014 05:43:19 Fabio Estevam wrote: > > > > [...] > > > > > > > Below is the log with linux-next kernel and earlyprintk enabled: > > > Does it also hang when you disable "earlyprintk"? A few weeks ago we > > > had a similar issue with i.MX6/PCI and "earlyprintk" (at the end it > > > was caused by a clock change for the UART when changing from the early > > > to the regular console). > > > > How can the UART clock have impact on the PCIe please ? > > Not to the PCIe hardware, it just hanged the kernel when the PCIe driver > came up (due to some of its messages it tries to output at this moment). Another hint, can a blocking msleep() hang the driver ? The driver probes in fs_initcall stage, I'm not sure if it cannot hit some kind of a problem when using the msleep() ? It's unlikely though ... Best regards, Marek Vasut