From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from fed1rmmtao11.cox.net (fed1rmmtao11.cox.net [68.230.241.28]) by ozlabs.org (Postfix) with ESMTP id A6EBC67A6F for ; Sat, 26 Feb 2005 11:30:20 +1100 (EST) Date: Fri, 25 Feb 2005 17:29:41 -0700 From: Matt Porter To: Ralph Siemsen Message-ID: <20050225172941.A30499@cox.net> References: <1628E43D99629C46988BE46087A3FBB91C4AA7@ep-01.EmbeddedPlanet.local> <421F89A0.8070502@sandburst.com> <20050225133055.A28918@cox.net> <421F966D.4060206@rossvideo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <421F966D.4060206@rossvideo.com>; from rsiemsen@rossvideo.com on Fri, Feb 25, 2005 at 04:19:41PM -0500 Cc: ppcembed Subject: Re: 2.6 4xx GPIO OCP driver? List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, Feb 25, 2005 at 04:19:41PM -0500, Ralph Siemsen wrote: > Matt Porter wrote: > > > I didn't bother merging it upstream at one time. It wasn't clear > > if the driver had any value over just mmaping /dev/mem to bang > > on the couple gpio registers directly. [...] > > Will that work on the 440 where the devices sit above 4GB mark? Or must > one rely on there being an existing TLB mapping to bring them into > 32-bit space? Ack...that's the one thing we are missing. :-/ I had forgotten that driver/char/mem.c calls remap_pfn_range() directly rather than io_remap_page_range(). Had it called the latter, we'd be OK since the "bigphys" fixup could take place. We can fix /dev/mem to call io_remap_page_range() when on ppc32 && 36-bit phys...other arches do similar tricks in that driver. If everybody is happy with mmaping /dev/mem then we can go try that route. -Matt