[PATCH 3.16 066/192] PCI: Mark Haswell Power Control Unit as having non-compliant BARs

Ben Hutchings
2017-10-09T13:37:52Z

From: Bjorn Helgaas <bhelgaas@google.com>

commit 6af7e4f77259ee946103387372cb159f2e99a6d4 upstream.

The Haswell Power Control Unit has a non-PCI register (CONFIG_TDP_NOMINAL)
where BAR 0 is supposed to be. This is erratum HSE43 in the spec update
referenced below:

The PCIe* Base Specification indicates that Configuration Space Headers
have a base address register at offset 0x10. Due to this erratum, the
Power Control Unit's CONFIG_TDP_NOMINAL CSR (Bus 1; Device 30; Function
3; Offset 0x10) is located where a base register is expected.

Mark the PCU as having non-compliant BARs so we don't try to probe any of
them. There are no other BARs on this device.

Rename the quirk so it's not Broadwell-specific.

Link: http://www.intel.com/content/www/us/en/processors/xeon/xeon-e5-v3-spec-update.html
Link: http://www.intel.com/content/www/us/en/processors/xeon/xeon-e5-v3-datasheet-vol-2.html (section 5.4, Device 30 Function 3)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=153881
Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Tested-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Myron Stowe <myron.stowe@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
arch/x86/pci/fixup.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)

--- a/arch/x86/pci/fixup.c
+++ b/arch/x86/pci/fixup.c
@@ -555,15 +555,21 @@ static void twinhead_reserve_killing_zon
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.
+ * Device [8086:2fc0]
+ * Erratum HSE43
+ * CONFIG_TDP_NOMINAL CSR Implemented at Incorrect Offset
+ * http://www.intel.com/content/www/us/en/processors/xeon/xeon-e5-v3-spec-update.html
*
- * See http://www.intel.com/content/www/us/en/processors/xeon/xeon-e5-v4-spec-update.html
- * entry BDF2.
+ * Devices [8086:6f60,6fa0,6fc0]
+ * Erratum BDF2
+ * PCI BARs in the Home Agent Will Return Non-Zero Values During Enumeration
+ * http://www.intel.com/content/www/us/en/processors/xeon/xeon-e5-v4-spec-update.html
*/
-static void pci_bdwep_bar(struct pci_dev *dev)
+static void pci_invalid_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);
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2fc0, pci_invalid_bar);
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x6f60, pci_invalid_bar);
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x6fa0, pci_invalid_bar);
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x6fc0, pci_invalid_bar);