From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Lindgren Subject: Re: [PATCH 1/2] OMAP3 PM: move omap3 sleep to ddr Date: Fri, 19 Nov 2010 08:09:24 -0800 Message-ID: <20101119160924.GR9264@atomide.com> References: <1290091906-32539-1-git-send-email-j-pihet@ti.com> <1290091906-32539-2-git-send-email-j-pihet@ti.com> <87tyjey6h3.fsf@deeprootsystems.com> <4CE55A88.6010300@ti.com> <20101118175215.GE9264@atomide.com> <20101118182752.GI9264@atomide.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mho-02-ewr.mailhop.org ([204.13.248.72]:46309 "EHLO mho-02-ewr.mailhop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753925Ab0KSQJj (ORCPT ); Fri, 19 Nov 2010 11:09:39 -0500 Content-Disposition: inline In-Reply-To: Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Jean Pihet Cc: Nishanth Menon , Kevin Hilman , linux-omap@vger.kernel.org, Vishwanath Sripathy , Jean Pihet-XID * Jean Pihet [101119 07:27]: > HI Tony, > > On Thu, Nov 18, 2010 at 7:34 PM, Jean Pihet wrote: > > On Thu, Nov 18, 2010 at 7:27 PM, Tony Lindgren wrote: > >> * Jean Pihet [101118 10:06]: > >>> On Thu, Nov 18, 2010 at 6:52 PM, Tony Lindgren wrote: > >>> > >>> About the DPLL lock: > >>> 1) wait_sdrc_ok is only called when back from the non-OFF modes, > >>> 2) I checked that when running wait_sdrc_ok the CORE is already out of > >>> idle and the DPLL is already locked. Note: l-o code has no support for > >>> the voltages OFF and the external clocks OFF. > >>> > >>> What to conclude from 1) and 2)? In my test setup ot looks like > >>> wait_sdrc_ok is of no use, but I agree this a premature conclusion. > >> > >> Yeah we should figure out in which cases wait_sdrc_ok is needed. > >> > >> BTW, are you sure you're hitting core idle in your tests? > > Yes it is OK from the console messages and the counters values in > > /debug/pm_debug/count. > > > > Let me confirm asap with the PRCM registers dump. > > Here is what I experimented: > 1) added a cache flush (v7_flush_kern_cache_all) just before WFI, in all cases, > 2) checked the real state entered in low power mode from the console > messages, the output of /debug/pm_debug/count and PRCM registers dump > > 2) is OK, which means that the RET and OFF modes are correctly hit. > > Can I conclude from 1) that the wake-up code is not running from the > cache in RETention? Sounds pretty safe to me then, thanks for testing. Now we just have to find out in which cases wait_sdrc_ok is needed.. Tony