From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758942AbcAKKGv (ORCPT ); Mon, 11 Jan 2016 05:06:51 -0500 Received: from foss.arm.com ([217.140.101.70]:53897 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758794AbcAKKGt (ORCPT ); Mon, 11 Jan 2016 05:06:49 -0500 Date: Mon, 11 Jan 2016 10:06:44 +0000 From: Catalin Marinas To: Lorenzo Pieralisi Cc: Zhaoyang Huang , zhaoyang.huang@spreadtrum.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, hanjun.guo@linaro.org, suzuki.poulose@arm.com, Mark Rutland Subject: Re: [RFC PATCH] Add IPI entry for CPU UP Message-ID: <20160111100644.GD9554@e104818-lin.cambridge.arm.com> References: <1452496240-21060-1-git-send-email-zhaoyang.huang@spreadtrum.com> <20160111095925.GA17852@red-moon> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160111095925.GA17852@red-moon> 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 On Mon, Jan 11, 2016 at 09:59:25AM +0000, Lorenzo Pieralisi wrote: > On Mon, Jan 11, 2016 at 03:10:40PM +0800, Zhaoyang Huang wrote: > > In some ARM SOCs, IPI interrupt is used for hotplug in one cpu, that is, > > sending a IPI to the core in WFI and powerdown status. So Add a IPI > > entry for handle this kind of cpu up interrupt > > On arm64 SOCs, with a mainline kernel, you can only hotplug CPUs out > and back in by using the PSCI firmware interface, which does not > require an IPI to boot a CPU, therefore this patch is useless. I fully agree. BTW, such patches should cc linux-arm-kernel@lists.infradead.org as well since they are ARM related. -- Catalin