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x86/PCI: Mark Broadwell-EP Home Agent 1 as having non-compliant BARs 

Commit b894157145 ("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: b894157145 ("x86/PCI: Mark Broadwell-EP Home Agent & PCU as having non-compliant BARs")
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Ingo Molnar <mingo@redhat.com>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Andi Kleen <ak@linux.intel.com>
This commit is contained in:
Prarit Bhargava 2016-05-11 12:27:15 -04:00 committed by Bjorn Helgaas
parent 92efb1bd9b
commit da77b67195
1 changed files with 7 additions and 0 deletions
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7
arch/x86/pci/fixup.c
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@ -552,9 +552,16 @@ static void twinhead_reserve_killing_zone(struct pci_dev *dev)
}
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);