From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id E5226DDF98 for ; Thu, 3 May 2007 12:11:54 +1000 (EST) Subject: Re: [PATCH] powermac: support G5 CPU hotplug From: Benjamin Herrenschmidt To: Segher Boessenkool In-Reply-To: <15a6025d58d0f62ee10efab20dc98278@kernel.crashing.org> References: <17969.56735.644629.328360@cargo.ozlabs.ibm.com> <1178086872.13233.27.camel@johannes.berg> <17976.28170.695715.416339@cargo.ozlabs.ibm.com> <1178116438.13233.65.camel@johannes.berg> <1178143429.17299.7.camel@localhost.localdomain> <17977.9796.15991.630737@cargo.ozlabs.ibm.com> <1178151690.17299.46.camel@localhost.localdomain> <15a6025d58d0f62ee10efab20dc98278@kernel.crashing.org> Content-Type: text/plain Date: Thu, 03 May 2007 12:11:47 +1000 Message-Id: <1178158307.17299.55.camel@localhost.localdomain> Mime-Version: 1.0 Cc: linuxppc-dev@ozlabs.org, Johannes Berg , Paul Mackerras List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , > Isn't it just a GPIO, like on older Macs? Of course, we > cannot bring a CPU back online after doing that so it's > pretty useless I suppose. We don't know for sure what the gpio does... wether it does a CPU soft reset or tickles the SPU to make it do special things that cause us to branch at 0x100. We do get the CPU back after that though. We use that to bring them in after boot. Ben.