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 --- include/linux/pci.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux') diff --git a/include/linux/pci.h b/include/linux/pci.h index 4869e66dd659..3b968d435895 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -451,6 +451,7 @@ struct pci_host_bridge { void *release_data; struct msi_controller *msi; unsigned int ignore_reset_delay:1; /* for entire hierarchy */ + unsigned int no_ext_tags:1; /* no Extended Tags */ /* Resource alignment requirements */ resource_size_t (*align_resource)(struct pci_dev *dev, const struct resource *res, -- cgit v1.3-6-gb490