From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753385Ab1IMMjO (ORCPT ); Tue, 13 Sep 2011 08:39:14 -0400 Received: from mx1.redhat.com ([209.132.183.28]:13814 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752553Ab1IMMjN (ORCPT ); Tue, 13 Sep 2011 08:39:13 -0400 Subject: Re: [PATCH 06/24] C6X: devicetree From: Mark Salter To: Arnd Bergmann Cc: devicetree-discuss@lists.ozlabs.org, Grant Likely , linux-kernel@vger.kernel.org Date: Tue, 13 Sep 2011 08:39:04 -0400 In-Reply-To: <6360771.ouEC5EKNMR@wuerfel> References: <1314826019-22330-1-git-send-email-msalter@redhat.com> <20110912201102.GF23345@ponder.secretlab.ca> <1315869636.11280.26.camel@deneb.redhat.com> <6360771.ouEC5EKNMR@wuerfel> Organization: Red Hat, Inc Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Message-ID: <1315917546.11280.38.camel@deneb.redhat.com> Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2011-09-13 at 08:43 +0200, Arnd Bergmann wrote: > On Monday 12 September 2011 19:20:35 Mark Salter wrote: > > On Mon, 2011-09-12 at 14:11 -0600, Grant Likely wrote: > > > On Wed, Aug 31, 2011 at 05:26:41PM -0400, Mark Salter wrote: > > > > + interrupt-controller; > > > > + #interrupt-cells = <1>; > > > > + compatible = "ti,c64x+core-pic"; > > > > > > The interrupt controller isn't addressable? Is it integrated into > > > the CPU? > > > > Yes, that core controller is controlled through registers accessed > > with special-purpose instructions, not MMIO. Other controllers, like > > megamodule and some as-yet unimplemented use MMIO. > > Are these instructions specific to the interrupt controller or > do they access a register space that can contain arbitrary > devices? > > If there is a separate address space for special devices, it might > be good to describe that in the device tree, like we do for PCI > I/O space. > It is a core register area. Similar to ARM or MIPS coprocessor registers. --Mark