diff options
Diffstat (limited to 'drivers/pci/pci.c')
| -rw-r--r-- | drivers/pci/pci.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 553ca6657955..4db261e13e69 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1299,6 +1299,38 @@ void pci_pm_init(struct pci_dev *dev) } } +/** + * pci_enable_ari - enable ARI forwarding if hardware support it + * @dev: the PCI device + */ +void pci_enable_ari(struct pci_dev *dev) +{ + int pos; + u32 cap; + u16 ctrl; + + if (!dev->is_pcie) + return; + + if (dev->pcie_type != PCI_EXP_TYPE_ROOT_PORT && + dev->pcie_type != PCI_EXP_TYPE_DOWNSTREAM) + return; + + pos = pci_find_capability(dev, PCI_CAP_ID_EXP); + if (!pos) + return; + + pci_read_config_dword(dev, pos + PCI_EXP_DEVCAP2, &cap); + if (!(cap & PCI_EXP_DEVCAP2_ARI)) + return; + + pci_read_config_word(dev, pos + PCI_EXP_DEVCTL2, &ctrl); + ctrl |= PCI_EXP_DEVCTL2_ARI; + pci_write_config_word(dev, pos + PCI_EXP_DEVCTL2, ctrl); + + dev->ari_enabled = 1; +} + int pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge) { |