From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752072AbaIYIZT (ORCPT ); Thu, 25 Sep 2014 04:25:19 -0400 Received: from metis.ext.pengutronix.de ([92.198.50.35]:42792 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750774AbaIYIZQ (ORCPT ); Thu, 25 Sep 2014 04:25:16 -0400 Date: Thu, 25 Sep 2014 10:25:06 +0200 From: Steffen Trumtrar To: atull@opensource.altera.com Cc: dinguyen@opensource.altera.com, linux@arm.linux.org.uk, yvanderv@opensource.altera.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, delicious.quinoa@gmail.com Subject: Re: [PATCH 2/2] socfpga: support suspend to ram Message-ID: <20140925082506.GC26991@pengutronix.de> References: <1411590449-9794-1-git-send-email-atull@opensource.altera.com> <1411590449-9794-3-git-send-email-atull@opensource.altera.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1411590449-9794-3-git-send-email-atull@opensource.altera.com> X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-IRC: #ptxdist @freenode X-Accept-Language: de,en X-Accept-Content-Type: text/plain X-Uptime: 10:22:07 up 15 days, 1:09, 75 users, load average: 0,08, 0,12, 0,13 User-Agent: Mutt/1.5.21 (2010-09-15) X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c0 X-SA-Exim-Mail-From: str@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi! On Wed, Sep 24, 2014 at 03:27:29PM -0500, atull@opensource.altera.com wrote: > From: Alan Tull > > Add code that requests that the sdr controller go into > self-refresh mode. This code is run from ocram. > > This patch assumes that u-boot has already configured sdr: > sdr.ctrlcfg.lowpwreq.selfrfshmask = 3 > sdr.ctrlcfg.lowpwrtiming.clkdisablecycles = 8 > sdr.ctrlcfg.dramtiming4.selfrfshexit = 512 > > How to suspend to ram: > $ echo enabled > \ > /sys/devices/soc/ffc02000.serial0/tty/ttyS0/power/wakeup > > $ echo -n mem > /sys/power/state > (...) Never looked into that, so maybe a stupid question: What happens if the bootloader (u-boot or other) didn't configure the sdr? Will it "just" not wake up again? Regards, Steffen -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |