From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932137AbYEMVBZ (ORCPT ); Tue, 13 May 2008 17:01:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1761124AbYEMVA7 (ORCPT ); Tue, 13 May 2008 17:00:59 -0400 Received: from e6.ny.us.ibm.com ([32.97.182.146]:40776 "EHLO e6.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760967AbYEMVA5 (ORCPT ); Tue, 13 May 2008 17:00:57 -0400 Date: Tue, 13 May 2008 14:00:54 -0700 From: Gary Hade To: Yinghai Lu Cc: Gary Hade , jbarnes@virtuousgeek.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org Subject: Re: [PATCH] PCI: boot parameter to avoid expansion ROM memory allocation Message-ID: <20080513210054.GB28815@us.ibm.com> References: <20080512205746.GB7401@us.ibm.com> <86802c440805121443r43cc7ceay4c05625f2878172e@mail.gmail.com> <20080512223005.GC7401@us.ibm.com> <86802c440805131048r2f027809pe972a5e27321c2b0@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <86802c440805131048r2f027809pe972a5e27321c2b0@mail.gmail.com> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 13, 2008 at 10:48:03AM -0700, Yinghai Lu wrote: > On Mon, May 12, 2008 at 3:30 PM, Gary Hade wrote: > > On Mon, May 12, 2008 at 02:43:44PM -0700, Yinghai Lu wrote: > > > On Mon, May 12, 2008 at 1:57 PM, Gary Hade wrote: > > > > > > > > --- linux-2.6.26-rc2/arch/x86/pci/common.c.orig 2008-05-12 10:59:58.000000000 -0700 > > > > +++ linux-2.6.26-rc2/arch/x86/pci/common.c 2008-05-12 11:22:05.000000000 -0700 > > > > @@ -121,6 +121,21 @@ void __init dmi_check_skip_isa_align(voi > > > > dmi_check_system(can_skip_pciprobe_dmi_table); > > > > } > > > > > > > > +static void __devinit pcibios_fixup_device_resources(struct pci_dev *dev) > > > > +{ > > > > + struct resource *rom_r = &dev->resource[PCI_ROM_RESOURCE]; > > > > + > > > > + if (pci_probe & PCI_NOASSIGN_ROMS) { > > > > + if (rom_r->parent) > > > > + return; > > > > + if (rom_r->start) { > > > > + /* we deal with BIOS assigned ROM later */ > > > > + return; > > > > + } > > > > + rom_r->start = rom_r->end = rom_r->flags = 0; > > > > + } > > > > +} > > > > + > > > > /* > > > > * Called after each bus is probed, but before its children > > > > * are examined. > > > > @@ -128,7 +143,11 @@ void __init dmi_check_skip_isa_align(voi > > > > > > > > void __devinit pcibios_fixup_bus(struct pci_bus *b) > > > > { > > > > + struct pci_dev *dev; > > > > + > > > > pci_read_bridge_bases(b); > > > > + list_for_each_entry(dev, &b->devices, bus_list) > > > > + pcibios_fixup_device_resources(dev); > > > > } > > > > > > or put check > > > + if (pci_probe & PCI_NOASSIGN_ROMS) { > > > > > > out of loop? > > > > I could certainly do that but I had intended that the new > > pcibios_fixup_device_resources function act as a container where > > other kinds of fixups could be added later. Do you (or others) > > think the additional cycles consumed by this approach are an > > issue here? > > ok, then wonder if we can don't assign roms for x86_64 by default. No, I don't think so. ..at least not by me! :) There were some lkml/linux-pci visible discussions back in November-December of last year where I floated the idea of making PCI expansion ROM memory non-assignment the default: http://marc.info/?l=linux-kernel&m=119742188215024&w=2 http://marc.info/?l=linux-kernel&m=119689499508369&w=2 I did not hear any objections so I went ahead and submitted the change which entered mainline at 2.6.25-rc1 but it was sternly evicted last week because of a reported regression that it had caused: http://marc.info/?l=linux-kernel&m=121029093331908&w=2 Attachments to http://bugs.freedesktop.org/show_bug.cgi?id=15523 indicate that a 2.6.25-rc2 x86_64 kernel was being used. > > can we use pci rom in 64 bit kernel? Sorry, not sure if I understand this question. I hope the above answers it. Gary -- Gary Hade System x Enablement IBM Linux Technology Center 503-578-4503 IBM T/L: 775-4503 garyhade@us.ibm.com http://www.ibm.com/linux/ltc