diff options
| -rw-r--r-- | drivers/pci/probe.c | 43 | ||||
| -rw-r--r-- | drivers/pci/quirks.c | 11 | ||||
| -rw-r--r-- | include/linux/pci.h | 3 |
3 files changed, 57 insertions, 0 deletions
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index c31310db0404..e6a917b4acd3 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1762,6 +1762,48 @@ static void pci_configure_extended_tags(struct pci_dev *dev) PCI_EXP_DEVCTL_EXT_TAG); } +/** + * pcie_relaxed_ordering_enabled - Probe for PCIe relaxed ordering enable + * @dev: PCI device to query + * + * Returns true if the device has enabled relaxed ordering attribute. + */ +bool pcie_relaxed_ordering_enabled(struct pci_dev *dev) +{ + u16 v; + + pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &v); + + return !!(v & PCI_EXP_DEVCTL_RELAX_EN); +} +EXPORT_SYMBOL(pcie_relaxed_ordering_enabled); + +static void pci_configure_relaxed_ordering(struct pci_dev *dev) +{ + struct pci_dev *root; + + /* PCI_EXP_DEVICE_RELAX_EN is RsvdP in VFs */ + if (dev->is_virtfn) + return; + + if (!pcie_relaxed_ordering_enabled(dev)) + return; + + /* + * For now, we only deal with Relaxed Ordering issues with Root + * Ports. Peer-to-Peer DMA is another can of worms. + */ + root = pci_find_pcie_root_port(dev); + if (!root) + return; + + if (root->dev_flags & PCI_DEV_FLAGS_NO_RELAXED_ORDERING) { + pcie_capability_clear_word(dev, PCI_EXP_DEVCTL, + PCI_EXP_DEVCTL_RELAX_EN); + dev_info(&dev->dev, "Disable Relaxed Ordering because the Root Port didn't support it\n"); + } +} + static void pci_configure_device(struct pci_dev *dev) { struct hotplug_params hpp; @@ -1769,6 +1811,7 @@ static void pci_configure_device(struct pci_dev *dev) pci_configure_mps(dev); pci_configure_extended_tags(dev); + pci_configure_relaxed_ordering(dev); memset(&hpp, 0, sizeof(hpp)); ret = pci_get_hp_params(dev, &hpp); diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 6967c6b4cf6b..61b59bfa7bfc 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -4016,6 +4016,17 @@ DECLARE_PCI_FIXUP_CLASS_EARLY(0x1797, 0x6869, PCI_CLASS_NOT_DEFINED, 8, quirk_tw686x_class); /* + * Some devices have problems with Transaction Layer Packets with the Relaxed + * Ordering Attribute set. Such devices should mark themselves and other + * Device Drivers should check before sending TLPs with RO set. + */ +static void quirk_relaxedordering_disable(struct pci_dev *dev) +{ + dev->dev_flags |= PCI_DEV_FLAGS_NO_RELAXED_ORDERING; + dev_info(&dev->dev, "Disable Relaxed Ordering Attributes to avoid PCIe Completion erratum\n"); +} + +/* * Per PCIe r3.0, sec 2.2.9, "Completion headers must supply the same * values for the Attribute as were supplied in the header of the * corresponding Request, except as explicitly allowed when IDO is used." diff --git a/include/linux/pci.h b/include/linux/pci.h index 4869e66dd659..29606fb89464 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -188,6 +188,8 @@ enum pci_dev_flags { * the direct_complete optimization. */ PCI_DEV_FLAGS_NEEDS_RESUME = (__force pci_dev_flags_t) (1 << 11), + /* Don't use Relaxed Ordering for TLPs directed at this device */ + PCI_DEV_FLAGS_NO_RELAXED_ORDERING = (__force pci_dev_flags_t) (1 << 12), }; enum pci_irq_reroute_variant { @@ -1125,6 +1127,7 @@ bool pci_check_pme_status(struct pci_dev *dev); void pci_pme_wakeup_bus(struct pci_bus *bus); void pci_d3cold_enable(struct pci_dev *dev); void pci_d3cold_disable(struct pci_dev *dev); +bool pcie_relaxed_ordering_enabled(struct pci_dev *dev); /* PCI Virtual Channel */ int pci_save_vc_state(struct pci_dev *dev); |