Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753018AbbFHJ3O (ORCPT ); Mon, 8 Jun 2015 05:29:14 -0400 Received: from pandora.arm.linux.org.uk ([78.32.30.218]:45142 "EHLO pandora.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752064AbbFHJ3D (ORCPT ); Mon, 8 Jun 2015 05:29:03 -0400 Date: Mon, 8 Jun 2015 10:28:53 +0100 From: Russell King - ARM Linux To: Caesar Wang Cc: Heiko Stuebner , dianders@chromium.org, Dmitry Torokhov , linux-rockchip@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v5 2/3] ARM: rockchip: ensure CPU to enter WFI/WFE state Message-ID: <20150608092852.GW7557@n2100.arm.linux.org.uk> References: <1433747496-7642-1-git-send-email-wxt@rock-chips.com> <1433747496-7642-3-git-send-email-wxt@rock-chips.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1433747496-7642-3-git-send-email-wxt@rock-chips.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1225 Lines: 39 On Mon, Jun 08, 2015 at 03:11:35PM +0800, Caesar Wang wrote: > diff --git a/arch/arm/mach-rockchip/platsmp.c b/arch/arm/mach-rockchip/platsmp.c > index bd40852..5bc2a89 100644 > --- a/arch/arm/mach-rockchip/platsmp.c > +++ b/arch/arm/mach-rockchip/platsmp.c > @@ -321,6 +321,9 @@ static void __init rockchip_smp_prepare_cpus(unsigned int max_cpus) > #ifdef CONFIG_HOTPLUG_CPU > static int rockchip_cpu_kill(unsigned int cpu) > { > + /* ensure CPU can enter the WFI/WFE state */ I would like to see a better comment here, describing what the problem is. Maybe something like this: /* * We need a delay here to ensure that the dying CPU can finish * executing v7_coherency_exit() and reach the WFI/WFE state * prior to having the power domain disabled. */ Thanks. > + mdelay(1); > + > pmu_set_power_domain(0 + cpu, false); > return 1; > } > -- > 1.9.1 > -- FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up according to speedtest.net. -- 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/