From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e31.co.us.ibm.com (e31.co.us.ibm.com [32.97.110.149]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e31.co.us.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id A6058DDEF6 for ; Sat, 22 Mar 2008 12:18:40 +1100 (EST) Received: from d03relay04.boulder.ibm.com (d03relay04.boulder.ibm.com [9.17.195.106]) by e31.co.us.ibm.com (8.13.8/8.13.8) with ESMTP id m2M1IbEA025924 for ; Fri, 21 Mar 2008 21:18:37 -0400 Received: from d03av04.boulder.ibm.com (d03av04.boulder.ibm.com [9.17.195.170]) by d03relay04.boulder.ibm.com (8.13.8/8.13.8/NCO v8.7) with ESMTP id m2M1IaeX156638 for ; Fri, 21 Mar 2008 19:18:36 -0600 Received: from d03av04.boulder.ibm.com (loopback [127.0.0.1]) by d03av04.boulder.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id m2M1Ia5t009228 for ; Fri, 21 Mar 2008 19:18:36 -0600 Date: Fri, 21 Mar 2008 20:17:04 -0500 From: Josh Boyer To: "Stephen Neuendorffer" Subject: Re: dcr stuff. Message-ID: <20080321201704.032999c3@zod.rchland.ibm.com> In-Reply-To: <20080321190524.4F3491CE0087@mail160-dub.bigfish.com> References: <20080321190524.4F3491CE0087@mail160-dub.bigfish.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Cc: linuxppc-dev@ozlabs.org, git-dev List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, 21 Mar 2008 12:05:40 -0700 "Stephen Neuendorffer" wrote: > > Is anybody working on the dcr infrastructure? > > In particular, there seems to be inconsistency between what the kernel > does and what ePAPR thinks it should. The code in the kernel selects > mmio or native access based on a Kconfig parameter and uses some device > tree parameters to correctly configure the mmio access, whereas ePAPR > doesn't seem to document all the device tree attributes (in particular, > dcr-mmio-stride and dcr-mmio-range) and provides a dynamic binding for > dcr-access-method... Code can be fixed if needs be. Keep in mind that ePAPR isn't publicly available yet. > Is there a plan here? (In particular, in FPGA designs, its possible to > have crazy things like multiple independent dcr busses, some using > native access, some using mmio. Or even if there is one bus, many of > the existing non-linux drivers we have assume native or mmio access. > I'd like to clean this up, obviously.. :) Clean it up how? I'd hate to add bloat to boards with native DCR access just because a few require oddities. If it ain't broke, don't fix it. josh