diff options
Diffstat (limited to 'drivers/pci')
-rw-r--r-- | drivers/pci/probe.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 6675a7a1b9fc..96dcd7b8303b 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -973,6 +973,8 @@ void set_pcie_port_type(struct pci_dev *pdev) { int pos; u16 reg16; + int type; + struct pci_dev *parent; pos = pci_find_capability(pdev, PCI_CAP_ID_EXP); if (!pos) @@ -982,6 +984,22 @@ void set_pcie_port_type(struct pci_dev *pdev) pdev->pcie_flags_reg = reg16; pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, ®16); pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD; + + /* + * A Root Port is always the upstream end of a Link. No PCIe + * component has two Links. Two Links are connected by a Switch + * that has a Port on each Link and internal logic to connect the + * two Ports. + */ + type = pci_pcie_type(pdev); + if (type == PCI_EXP_TYPE_ROOT_PORT) + pdev->has_secondary_link = 1; + else if (type == PCI_EXP_TYPE_UPSTREAM || + type == PCI_EXP_TYPE_DOWNSTREAM) { + parent = pci_upstream_bridge(pdev); + if (!parent->has_secondary_link) + pdev->has_secondary_link = 1; + } } void set_pcie_hotplug_bridge(struct pci_dev *pdev) |