From 62ce94a7a5a54aac80975f5e6731707225d4077e Mon Sep 17 00:00:00 2001 From: Sinan Kaya Date: Wed, 12 Jul 2017 00:04:14 -0400 Subject: PCI: Mark Broadcom HT2100 Root Port Extended Tags as broken Per PCIe r3.1, sec 2.2.6.2 and 7.8.4, a Requester may not use 8-bit Tags unless its Extended Tag Field Enable is set, but all Receivers/Completers must handle 8-bit Tags correctly regardless of their Extended Tag Field Enable. Some devices do not handle 8-bit Tags as Completers, so add a quirk for them. If we find such a device, we disable Extended Tags for the entire hierarchy to make peer-to-peer DMA possible. The Broadcom HT2100 seems to have issues with handling 8-bit tags. Mark it as broken. The pci_walk_bus() in the quirk handles devices we've enumerated in the past, and pci_configure_device() handles devices we enumerate in the future. Fixes: 60db3a4d8cc9 ("PCI: Enable PCIe Extended Tags if supported") Link: https://bugzilla.redhat.com/show_bug.cgi?id=1467674 Reported-and-tested-by: Wim ten Have Signed-off-by: Sinan Kaya [bhelgaas: changelog, tweak messages, rename bit and quirk] Signed-off-by: Bjorn Helgaas --- drivers/pci/quirks.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'drivers/pci/quirks.c') diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 6967c6b4cf6b..f135765555c9 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -4681,3 +4681,19 @@ 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_no_ext_tags(struct pci_dev *pdev) +{ + struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus); + + if (!bridge) + return; + + bridge->no_ext_tags = 1; + dev_info(&pdev->dev, "disabling Extended Tags (this device can't handle them)\n"); + + pci_walk_bus(bridge->bus, pci_configure_extended_tags, NULL); +} +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SERVERWORKS, 0x0140, quirk_no_ext_tags); +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SERVERWORKS, 0x0142, quirk_no_ext_tags); +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SERVERWORKS, 0x0144, quirk_no_ext_tags); -- cgit v1.2.3