From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934675AbcHNLrb (ORCPT ); Sun, 14 Aug 2016 07:47:31 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:52394 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965426AbcHNLcG (ORCPT ); Sun, 14 Aug 2016 07:32:06 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Ingo Molnar" , "Prarit Bhargava" , "Thomas Gleixner" , "H. Peter Anvin" , "Bjorn Helgaas" , "Andi Kleen" Date: Sat, 13 Aug 2016 18:42:58 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 23/94] x86/PCI: Mark Broadwell-EP Home Agent 1 as having non-compliant BARs In-Reply-To: X-SA-Exim-Connect-IP: 92.40.249.202 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.82-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Prarit Bhargava commit da77b67195de1c65bef4908fa29967c4d0af2da2 upstream. Commit b894157145e4 ("x86/PCI: Mark Broadwell-EP Home Agent & PCU as having non-compliant BARs") marked Home Agent 0 & PCU has having non-compliant BARs. Home Agent 1 also has non-compliant BARs. Mark Home Agent 1 as having non-compliant BARs so the PCI core doesn't touch them. The problem with these devices is documented in the Xeon v4 specification update: BDF2 PCI BARs in the Home Agent Will Return Non-Zero Values During Enumeration Problem: During system initialization the Operating System may access the standard PCI BARs (Base Address Registers). Due to this erratum, accesses to the Home Agent BAR registers (Bus 1; Device 18; Function 0,4; Offsets (0x14-0x24) will return non-zero values. Implication: The operating system may issue a warning. Intel has not observed any functional failures due to this erratum. Link: http://www.intel.com/content/www/us/en/processors/xeon/xeon-e5-v4-spec-update.html Fixes: b894157145e4 ("x86/PCI: Mark Broadwell-EP Home Agent & PCU as having non-compliant BARs") Signed-off-by: Prarit Bhargava Signed-off-by: Bjorn Helgaas CC: Thomas Gleixner CC: Ingo Molnar CC: "H. Peter Anvin" CC: Andi Kleen Signed-off-by: Ben Hutchings --- arch/x86/pci/fixup.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/arch/x86/pci/fixup.c +++ b/arch/x86/pci/fixup.c @@ -539,9 +539,16 @@ static void __devinit twinhead_reserve_k } DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x27B9, twinhead_reserve_killing_zone); +/* + * Broadwell EP Home Agent BARs erroneously return non-zero values when read. + * + * See http://www.intel.com/content/www/us/en/processors/xeon/xeon-e5-v4-spec-update.html + * entry BDF2. + */ static void pci_bdwep_bar(struct pci_dev *dev) { dev->non_compliant_bars = 1; } +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x6f60, pci_bdwep_bar); DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x6fa0, pci_bdwep_bar); DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x6fc0, pci_bdwep_bar);