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 ESMTPS id 1BC85DDF19 for ; Thu, 25 Sep 2008 07:23:38 +1000 (EST) Subject: Re: [PATCH HACK] powerpc: quick hack to get a functional eHEA with hardirq preemption From: Benjamin Herrenschmidt To: Milton Miller In-Reply-To: <0fa2693104ff3250114d82837911b9e8@bga.com> References: <200809231743.23828.ossthema@de.ibm.com> <20080915100406.342e027a@bull.net> <200809240958.m8O9wM7k010996@sullivan.realtime.net> <20080924143055.6102f317@bull.net> <0fa2693104ff3250114d82837911b9e8@bga.com> Content-Type: text/plain Date: Thu, 25 Sep 2008 07:16:45 +1000 Message-Id: <1222291005.8277.86.camel@pasglop> Mime-Version: 1.0 Cc: linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, Sebastien Dugue , Jan-Bernd Themann , Paul Mackerras , Christoph Raisch Reply-To: benh@kernel.crashing.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, 2008-09-24 at 11:42 -0500, Milton Miller wrote: > > I was trying to understand why the mask and early eoi, but I guess its > to handle other more limited interrupt controllers where the interrupts > stack in hardware instead of software. No Milton, we must do it that way, because the EOI must be done on the right CPU even on XICS, or we won't get the CPU priority back properly. Ben.