Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752464AbaFJPtc (ORCPT ); Tue, 10 Jun 2014 11:49:32 -0400 Received: from mail-qa0-f53.google.com ([209.85.216.53]:37733 "EHLO mail-qa0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750771AbaFJPta (ORCPT ); Tue, 10 Jun 2014 11:49:30 -0400 Date: Tue, 10 Jun 2014 11:49:27 -0400 (EDT) From: Nicolas Pitre To: Doug Anderson cc: Chander Kashyap , Lorenzo Pieralisi , Kukjin Kim , Abhilash Kesavan , Andrew Bresticker , Inderpal Singh , Thomas Abraham , "olof@lixom.net" , Tushar Behera , Kevin Hilman , Javier Martinez Canillas , "linux-samsung-soc@vger.kernel.org" , "linux@arm.linux.org.uk" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] ARM: EXYNOS: mcpm: Don't rely on firmware's secondary_cpu_start In-Reply-To: Message-ID: References: <1402090985-8061-1-git-send-email-dianders@chromium.org> <20140607181221.GB25068@e102568-lin.cambridge.arm.com> <20140609223831.GB16889@e102568-lin.cambridge.arm.com> User-Agent: Alpine 2.11 (LFD 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 10 Jun 2014, Doug Anderson wrote: > My S-state knowledge is not strong, but I believe that Lorenzo's > questions matter if we're using S2 for CPUidle (where we actually turn > off power and hot unplug CPUs) but not when we're using S1 for CPUidle > (where we just enter WFI/WFE). > > I believe that in ChromeOS we use S1 CPUidle and that it works fine. > We've never implemented S2 that I'm aware of. You'll have to rely on MCPM for that. That's probably why it hasn't been implemented before. Nicolas -- 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/