[PATCH V3 1/2] PCI: Add Extended Tags quirk for Broadcom HT2100 Root Port

From: Sinan Kaya
Date: Tue Jul 11 2017 - 11:25:46 EST


All PCIe devices are expected to be able to handle 8-bit tags.
'commit 60db3a4d8cc9 ("PCI: Enable PCIe Extended Tags if supported")'
enabled extended tags for all devices based on the spec direction.

The Broadcom HT2100 seems to be having issues with handling
8-bit tags. Mark it as broken.

Reported-by: Wim ten Have <wim.ten.have@xxxxxxxxxx>
Link: https://bugzilla.redhat.com/show_bug.cgi?id=1467674
Fixes: 60db3a4d8cc9 ("PCI: Enable PCIe Extended Tags if supported")
Signed-off-by: Sinan Kaya <okaya@xxxxxxxxxxxxxx>
---
drivers/pci/quirks.c | 12 ++++++++++++
include/linux/pci.h | 1 +
2 files changed, 13 insertions(+)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 085fb78..073d5dd 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -4664,3 +4664,15 @@ static void quirk_intel_no_flr(struct pci_dev *dev)
}
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x1502, quirk_intel_no_flr);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x1503, quirk_intel_no_flr);
+
+static void quirk_exttags_completer(struct pci_dev *pdev)
+{
+ /* This device cannot handle 256 tags as a completer */
+ pdev->broken_exttags_completer = 1;
+}
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SERVERWORKS, 0x0140,
+ quirk_exttags_completer);
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SERVERWORKS, 0x0142,
+ quirk_exttags_completer);
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SERVERWORKS, 0x0144,
+ quirk_exttags_completer);
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 8039f9f..0b9f42d 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -376,6 +376,7 @@ struct pci_dev {
unsigned int irq_managed:1;
unsigned int has_secondary_link:1;
unsigned int non_compliant_bars:1; /* broken BARs; ignore them */
+ unsigned int broken_exttags_completer:1;
pci_dev_flags_t dev_flags;
atomic_t enable_cnt; /* pci_enable_device has been called */

--
1.9.1