diff options
| author |   Alexandru Gagniuc <mr.nuke.me@gmail.com> | 2018-08-06 18:25:35 -0500 |
|---|---|---|
| committer |   Bjorn Helgaas <bhelgaas@google.com> | 2018-08-10 12:29:04 -0500 |
| commit | 2d1ce5ec2117d16047334a1aa4b62e0cfb5a0605 (patch) | |
| tree | 61d71cf43436d8929699cb9032daa7ae623e87d0 /drivers/pci/pci.h | |
| parent | PCI: Workaround IDT switch ACS Source Validation erratum (diff) | |
| download | linux-dev-2d1ce5ec2117d16047334a1aa4b62e0cfb5a0605.tar.xz linux-dev-2d1ce5ec2117d16047334a1aa4b62e0cfb5a0605.zip | |
PCI: Check for PCIe Link downtraining
When both ends of a PCIe Link are capable of a higher bandwidth than is
currently in use, the Link is said to be "downtrained". A downtrained Link
may indicate hardware or configuration problems in the system, but it's
hard to identify such Links from userspace.
Refactor pcie_print_link_status() so it continues to always print PCIe
bandwidth information, as several NIC drivers desire.
Add a new internal __pcie_print_link_status() to emit a message only when a
device's bandwidth is constrained by the fabric and call it from the PCI
core for all devices, which identifies all downtrained Links. It also
emits messages for a few cases that are technically not downtrained, such
as a x4 device in an open-ended x1 slot.
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
[bhelgaas: changelog, move __pcie_print_link_status() declaration to
drivers/pci/, rename pcie_check_upstream_link() to
pcie_report_downtraining()]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Diffstat (limited to 'drivers/pci/pci.h')
| -rw-r--r-- | drivers/pci/pci.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 70808c168fb9..ce880dab5bc8 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -263,6 +263,7 @@ enum pci_bus_speed pcie_get_speed_cap(struct pci_dev *dev); enum pcie_link_width pcie_get_width_cap(struct pci_dev *dev); u32 pcie_bandwidth_capable(struct pci_dev *dev, enum pci_bus_speed *speed, enum pcie_link_width *width); +void __pcie_print_link_status(struct pci_dev *dev, bool verbose); /* Single Root I/O Virtualization */ struct pci_sriov { |