From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Fritz Subject: Re: [Bug] am33xx: Basic suspend resume support: Doesn't resume Date: Fri, 06 Dec 2013 00:43:51 +0100 Message-ID: <1386287031.3749.2.camel@mars> References: <1386250976.3880.91.camel@mars> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-bk0-f45.google.com ([209.85.214.45]:59707 "EHLO mail-bk0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756005Ab3LEXnz (ORCPT ); Thu, 5 Dec 2013 18:43:55 -0500 Received: by mail-bk0-f45.google.com with SMTP id mx13so32547bkb.32 for ; Thu, 05 Dec 2013 15:43:54 -0800 (PST) In-Reply-To: <1386250976.3880.91.camel@mars> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: t-kristo@ti.com Cc: Russ Dill , Vaibhav Bedia , linux-omap@vger.kernel.org, Daniel Mack On Thu, 2013-12-05 at 14:42 +0100, Christoph Fritz wrote: > Hi, > > I'm having here a custom am335x board with DDR3 equipped trying to > setup suspend/resume support. I have tested this with the ancient > TI-PSP-3.2 Kernel and current 3.13-rc plus some pm patches. > > Problem: After suspending the device, it doesn't resume (freeze): > > echo "mem" > /sys/power/state > [ 103.020845] PM: Syncing filesystems ... done. > [ 103.055549] Freezing user space processes ... (elapsed 0.003 seconds) done. > [ 103.066696] Freezing remaining freezable tasks ... (elapsed 0.002 seconds) done. > [ 103.077506] PM: Sending message for entering DeepSleep mode > [ 103.099896] PM: suspend of devices complete after 11.951 msecs > [ 103.110894] PM: late suspend of devices complete after 4.659 msecs > [ 103.122599] PM: noirq suspend of devices complete after 5.032 msecs > > As a wakeup source I'm currently using gpio0_12. > > Triggering the reset button (am335x-pin: WARMRSTn) in suspend-mode has > no effect, which is fine. But after changing the signal on the wakeup > source (here gpio0_12), triggering a reset works fine again. > > So it seems to me that somewhere in the wakeup-process is a bug. > > Could this be related to DDR3? Apart from that, this custom board here > is pretty similar to the ti-evm board wich works fine. > > In oder to test, I've shrunken the kernel to minimal driver support to > sort out as much as possible segfaults in resume functions. > > With a view to be able to debug this further, I just ordered an openocd > jtag adapter. > > Any comments, ideas, tips, ..? Update: It has definitely something to do with DDR3. I'll investigate this further. By the way, is there a TI-Board with DDR3 and working suspend-resume? Thanks -- Christoph