From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yinghai Lu Subject: Re: [PATCH] x86/pci: do assign root bus res if _CRS is used Date: Mon, 27 Apr 2009 19:07:01 -0700 Message-ID: <86802c440904271907r335f7834p8f03aa13bc6515e8@mail.gmail.com> References: <49ED22EC.2040204@kernel.org> <200904271439.37396.bjorn.helgaas@hp.com> <86802c440904271400q379da621ja808c96152c3fb8b@mail.gmail.com> <200904271624.17295.bjorn.helgaas@hp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <200904271624.17295.bjorn.helgaas@hp.com> Sender: linux-pci-owner@vger.kernel.org To: Bjorn Helgaas Cc: Jesse Barnes , Ingo Molnar , "H. Peter Anvin" , Thomas Gleixner , "linux-kernel@vger.kernel.org" , linux-pci@vger.kernel.org, Gary Hade , Alex Chiang , linux-acpi@vger.kernel.org, Matthew Wilcox List-Id: linux-acpi@vger.kernel.org On Mon, Apr 27, 2009 at 3:24 PM, Bjorn Helgaas w= rote: > On Monday 27 April 2009 03:00:16 pm Yinghai Lu wrote: >> On Mon, Apr 27, 2009 at 1:39 PM, Bjorn Helgaas wrote: >> >> other system may have broken _CRS. >> > >> > Do you have examples of problems here, or are you just worried tha= t >> > there *may* be problems? >> one system with three chains... with pci=3Duse_crs >> [ =A0 =A09.365669] pci_bus 0000:00: resource 0 io: =A0[0x00-0x3af] >> [ =A0 =A09.371065] pci_bus 0000:00: resource 1 io: =A0[0x3e0-0xcf7] >> [ =A0 =A09.376551] pci_bus 0000:00: resource 2 io: =A0[0x3b0-0x3bb] >> [ =A0 =A09.382028] pci_bus 0000:00: resource 3 io: =A0[0x3c0-0x3df] >> [ =A0 =A09.387513] pci_bus 0000:00: resource 4 io: =A0[0xd00-0xefff] >> [ =A0 =A09.393077] pci_bus 0000:00: resource 5 mem: [0x0a0000-0x0bff= ff] >> [ =A0 =A09.399084] pci_bus 0000:00: resource 6 mem: [0x0d0000-0x0dff= ff] >> [ =A0 =A09.405089] pci_bus 0000:00: resource 7 mem: [0xdd000000-0xdf= ffffff] >> [ =A0 =A09.505332] pci_bus 0000:40: resource 0 io: =A0[0x5000-0x8fff= ] >> [ =A0 =A09.510991] pci_bus 0000:40: resource 1 mem: [0xdb000000-0xdc= ffffff] >> [ =A0 =A09.553378] pci_bus 0000:80: resource 0 io: =A0[0x1000-0x4fff= ] >> [ =A0 =A09.559036] pci_bus 0000:80: resource 1 mem: [0xda000000-0xda= ffffff] >> >> without that: amd_bus.c will read that from pci conf space >> [ =A0 =A09.310965] pci_bus 0000:00: resource 0 io: =A0[0x9000-0xefff= ] >> [ =A0 =A09.316621] pci_bus 0000:00: resource 1 io: =A0[0x00-0xfff] >> [ =A0 =A09.322020] pci_bus 0000:00: resource 2 mem: [0xdd000000-0xdf= ffffff] >> [ =A0 =A09.328373] pci_bus 0000:00: resource 3 mem: [0x0a0000-0x0bff= ff] >> [ =A0 =A09.334378] pci_bus 0000:00: resource 4 mem: [0xc0000000-0xd9= ffffff] >> [ =A0 =A09.340731] pci_bus 0000:00: resource 5 mem: [0xf0000000-0xff= ffffff] >> [ =A0 =A09.347084] pci_bus 0000:00: resource 6 mem: [0x840000000-0xf= cffffffff] >> [ =A0 =A09.444440] pci_bus 0000:40: resource 0 io: =A0[0x5000-0x8fff= ] >> [ =A0 =A09.450099] pci_bus 0000:40: resource 1 io: =A0[0xf000-0xffff= ] >> [ =A0 =A09.455757] pci_bus 0000:40: resource 2 mem: [0xdb000000-0xdc= ffffff] >> [ =A0 =A09.498118] pci_bus 0000:80: resource 0 io: =A0[0x1000-0x4fff= ] >> [ =A0 =A09.503777] pci_bus 0000:80: resource 1 mem: [0xda000000-0xda= ffffff] > > It's interesting that many of the differences involve the legacy > VGA I/O ports in the 0x3b0-0x3df range. =A0My guess is that the AMD > chipset has special routing for those ranges. =A0If it didn't, it > would be difficult to support VGA devices under the other two > root bridges. =A0Maybe that VGA routing doesn't show up in the > bridge's PCI config space. =A0Can you tell from the ASL whether the > root bridge _SRS/_PRS/_CRS methods handle the VGA ranges specially? > > One of the differences is that PCI config space shows a 64-bit region > (bus 0000:00 mem 0x840000000-0xfcffffffff) that doesn't show up in > the _CRS info. =A0But the _CRS parsing depends on acpi_resource_to_ad= dress64(), > which doesn't know about the ACPI_RESOURCE_TYPE_EXTENDED_ADDRESS64 > descriptors added in ACPI 3.0. =A0So this difference could be a resul= t > of that Linux bug. =A0It'd be interesting to see whether the test pat= ch > below makes a difference. will check it. > > The PCI config space region 0xf0000000-0xffffffff, also on bus 0000:0= 0, > looks suspicious to me. =A0I thought that area contained a bunch of > BIOS-y things like reset vectors and local APICs. in the amd_bus.c, will put left over resource to def HT chain. YH