Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932351AbbBZW7I (ORCPT ); Thu, 26 Feb 2015 17:59:08 -0500 Received: from pandora.arm.linux.org.uk ([78.32.30.218]:37981 "EHLO pandora.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753643AbbBZW7G (ORCPT ); Thu, 26 Feb 2015 17:59:06 -0500 Date: Thu, 26 Feb 2015 22:58:53 +0000 From: Russell King - ARM Linux To: Rob Herring Cc: Mathieu Poirier , Will Deacon , "linux-api@vger.kernel.org" , Jonathan Corbet , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-doc@vger.kernel.org" Subject: Re: [PATCH v2] coresight-stm: adding driver for CoreSight STM component Message-ID: <20150226225853.GM8656@n2100.arm.linux.org.uk> References: <1424907152-18808-1-git-send-email-mathieu.poirier@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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 Content-Length: 956 Lines: 21 On Thu, Feb 26, 2015 at 04:24:53PM -0600, Rob Herring wrote: > We really shouldn't do private implementation here. It there really > any reason not to allow readq/writeq generically for 32-bit or just > for arm32? My argument has always been that drivers should do the emulation of 64-bit accesses when there is no native support. IO registers tend to have side effects when read/written. How do we know whether the low-half or the high-half should be written first? This isn't something that an architecture can really dictate. What may be right for one hardware device may not be correct for another. -- FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up according to speedtest.net. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/