From owner-freebsd-arch@FreeBSD.ORG Fri Oct 16 18:27:47 2009 Return-Path: Delivered-To: freebsd-arch@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 32E5B1065672; Fri, 16 Oct 2009 18:27:47 +0000 (UTC) (envelope-from imp@bsdimp.com) Received: from harmony.bsdimp.com (bsdimp.com [199.45.160.85]) by mx1.freebsd.org (Postfix) with ESMTP id C76578FC25; Fri, 16 Oct 2009 18:27:46 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by harmony.bsdimp.com (8.14.3/8.14.1) with ESMTP id n9GIPdm4055539; Fri, 16 Oct 2009 12:25:39 -0600 (MDT) (envelope-from imp@bsdimp.com) Date: Fri, 16 Oct 2009 12:25:39 -0600 (MDT) Message-Id: <20091016.122539.-1383511515.imp@bsdimp.com> To: jkim@FreeBSD.org From: "M. Warner Losh" In-Reply-To: <200910161400.00564.jkim@FreeBSD.org> References: <4890688A-D2DB-431C-ADB6-03A39A8FD10E@mac.com> <200910161346.03066.jkim@FreeBSD.org> <200910161400.00564.jkim@FreeBSD.org> X-Mailer: Mew version 5.2 on Emacs 21.3 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: xcllnt@mac.com, freebsd-arch@FreeBSD.org Subject: Re: x86BIOS and the ISA bus and low memory in general... X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 16 Oct 2009 18:27:47 -0000 In message: <200910161400.00564.jkim@FreeBSD.org> Jung-uk Kim writes: : On Friday 16 October 2009 01:46 pm, Jung-uk Kim wrote: : > On Thursday 15 October 2009 04:37 pm, Marcel Moolenaar wrote: : > > On Oct 15, 2009, at 12:45 PM, M. Warner Losh wrote: : > > > [[ redirected to arch@ ]] : > > > : > > > In message: <200910151431.53236.jkim@FreeBSD.org> : > > > Jung-uk Kim writes: : > > > : > > > : > > > : This is actually very interesting discussion for me because : > > > : one of : > > > : > > > my : > > > : > > > : pet projects is extending x86bios to support non-PC : > > > : architectures. If anyone is interested, the current source : > > > : tarball is here: : > > > : : > > > : http://people.freebsd.org/~jkim/x86bios-20091015.tar.bz2 : > > > : : > > > : Especially, please see the code around #ifdef : > > > : X86BIOS_COMPAT_ARCH. Basically, mapping I/O ports and orm(4) : > > > : is missing. We don't have : > > > : > > > to : > > > : > > > : implement I/O ports but orm(4) vs. bus_space(9) is critical : > > > : to make it a reality. Please consider it as a real practical : > > > : example for orm, not just a blackhole driver. :-) : > > > : > > > I thought that most video cards had I/O ports as well as video : > > > RAM that needed to be mapped... Am I crazy? : > > : > > It depends on the platform. On an Itanium machine I have the : > > VGA frame buffer is at physical address 0xA0000-0xC0000. : > : > The address is the same, then. :-) : > : > > The only requirement is that you use non-cached I/O, otherwise : > > you get a machine check. This can mean a non-identity mapping : > > or not. It all depends... : > : > I couldn't find a way to manipulate memory attribute directly on : > ia64, i.e., mem_range_attr_{get,set}() and pmap_mapdev_attr() only : > exist on amd64 and i386. Does pmap_mapdev() set the attribute as : > UC? : : It seems pmap_mapdev() on ia64 uses IA64_PHYS_TO_RR6() macro. If I : read the source correctly, then it is gives UC mapped "view" of the : physical address, right? If so, orm(4) can simply do : pmap_mapdev()/pmap_unmapdev() around bus_space_read_region_1(). Am I : right? I don't think that's the right solution here. The pmap_mapdev stuff should happen when the resource is activated... Warner