From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752659Ab0CQD0d (ORCPT ); Tue, 16 Mar 2010 23:26:33 -0400 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:45424 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752579Ab0CQD0c (ORCPT ); Tue, 16 Mar 2010 23:26:32 -0400 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 Message-ID: <4BA04BB9.2090501@jp.fujitsu.com> Date: Wed, 17 Mar 2010 12:25:45 +0900 From: Kenji Kaneshige User-Agent: Thunderbird 2.0.0.23 (Windows/20090812) MIME-Version: 1.0 To: Bjorn Helgaas CC: Jesse Barnes , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, "Rafael J. Wysocki" , Yanko Kaneti , Linus Torvalds , Thomas Renninger , maciej.rutecki@gmail.com Subject: Re: [PATCH v1 2/3] x86/PCI: trim _CRS windows when they conflict with previous reservations References: <20100311235954.4355.23100.stgit@bob.kio> <20100312000114.4355.58189.stgit@bob.kio> In-Reply-To: <20100312000114.4355.58189.stgit@bob.kio> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Bjorn Helgaas wrote: > Yanko's GA-MA78GM-S2H (BIOS F11) reports a host bridge window that overlaps > system memory: > > PCI window: [mem 0xcff00000-0x10ed0ffff] > System RAM: [mem 0x100000000-0x22fffffff] > > We can be pretty confident that the System RAM region is correct (if it > were wrong, we'd crash as soon as we tried to use any memory in that area), > so this patch tries to correct the PCI window by trimming it so it doesn't > conflict with any previous reservations. > Though I might misunderstand something, it looks Yanko's machine specific workaround. I'm wondering if trimming _CRS is a generic workaround for broken _CRS machine. How about doing this when GA-MA78GM-S2H (BIOS F11) (and known machines that have the same problem) is detected? Or how about switching nocrs mode if the problem (resource conflict) is detected? Thanks, Kenji Kaneshige > http://bugzilla.kernel.org/show_bug.cgi?id=15480 > > Signed-off-by: Bjorn Helgaas > Reported-by: Yanko Kaneti > --- > > arch/x86/pci/acpi.c | 48 +++++++++++++++++++++++++++++++++++------------- > 1 files changed, 35 insertions(+), 13 deletions(-) > > > diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c > index 6e22454..d255ce8 100644 > --- a/arch/x86/pci/acpi.c > +++ b/arch/x86/pci/acpi.c > @@ -114,11 +114,19 @@ align_resource(struct acpi_device *bridge, struct resource *res) > } > } > > +static bool > +resource_contains(struct resource *res, resource_size_t n) > +{ > + if (n < res->start || n > res->end) > + return false; > + return true; > +} > + > static acpi_status > setup_resource(struct acpi_resource *acpi_res, void *data) > { > struct pci_root_info *info = data; > - struct resource *res; > + struct resource *res, *conflict; > struct acpi_resource_address64 addr; > acpi_status status; > unsigned long flags; > @@ -157,21 +165,35 @@ setup_resource(struct acpi_resource *acpi_res, void *data) > return AE_OK; > } > > - if (insert_resource(root, res)) { > + conflict = insert_resource_conflict(root, res); > + while (conflict) { > dev_err(&info->bridge->dev, > - "can't allocate host bridge window %pR\n", res); > - } else { > - pci_bus_add_resource(info->bus, res, 0); > - info->res_num++; > - if (addr.translation_offset) > - dev_info(&info->bridge->dev, "host bridge window %pR " > - "(PCI address [%#llx-%#llx])\n", > - res, res->start - addr.translation_offset, > - res->end - addr.translation_offset); > + "host bridge window %pR conflicts with %s %pR\n", > + res, conflict->name, conflict); > + > + if (resource_contains(res, conflict->end)) > + res->start = conflict->end + 1; > + else if (resource_contains(res, conflict->start)) > + res->end = conflict->start - 1; > else > - dev_info(&info->bridge->dev, > - "host bridge window %pR\n", res); > + return AE_OK; > + > + if (res->start >= res->end) > + return AE_OK; > + > + conflict = insert_resource_conflict(root, res); > } > + > + pci_bus_add_resource(info->bus, res, 0); > + info->res_num++; > + if (addr.translation_offset) > + dev_info(&info->bridge->dev, "host bridge window %pR " > + "(PCI address [%#llx-%#llx])\n", > + res, res->start - addr.translation_offset, > + res->end - addr.translation_offset); > + else > + dev_info(&info->bridge->dev, > + "host bridge window %pR\n", res); > return AE_OK; > } > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > >