diff options
| author | Yijing Wang <wangyijing@huawei.com> | 2013-01-15 04:12:16 +0100 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2013-01-24 19:42:14 +0100 |
| commit | b0cc6020e1cc62f1253215f189611b34be4a83c7 (patch) | |
| tree | fd798c95fe1ebe506dc2a3d2e7576777393408e6 | |
| parent | Linux 3.8-rc2 (diff) | |
| download | linux-b0cc6020e1cc62f1253215f189611b34be4a83c7.tar.xz linux-b0cc6020e1cc62f1253215f189611b34be4a83c7.zip | |
PCI: Enable ARI if dev and upstream bridge support it; disable otherwise
Currently, we enable ARI in a device's upstream bridge if the bridge and
the device support it. But we never disable ARI, even if the device is
removed and replaced with a device that doesn't support ARI.
This means that if we hot-remove an ARI device and replace it with a
non-ARI multi-function device, we find only function 0 of the new device
because the upstream bridge still has ARI enabled, and next_ari_fn()
only returns function 0 for the new non-ARI device.
This patch disables ARI in the upstream bridge if the device doesn't
support ARI. See the PCIe spec, r3.0, sec 6.13.
[bhelgaas: changelog, function comment]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
| -rw-r--r-- | drivers/pci/pci.c | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 5cb5820fae40..8b47f70b7d8f 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -2069,6 +2069,9 @@ void pci_free_cap_save_buffers(struct pci_dev *dev) /** * pci_enable_ari - enable ARI forwarding if hardware support it * @dev: the PCI device + * + * If @dev and its upstream bridge both support ARI, enable ARI in the + * bridge. Otherwise, disable ARI in the bridge. */ void pci_enable_ari(struct pci_dev *dev) { @@ -2078,9 +2081,6 @@ void pci_enable_ari(struct pci_dev *dev) if (pcie_ari_disabled || !pci_is_pcie(dev) || dev->devfn) return; - if (!pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI)) - return; - bridge = dev->bus->self; if (!bridge) return; @@ -2089,8 +2089,15 @@ void pci_enable_ari(struct pci_dev *dev) if (!(cap & PCI_EXP_DEVCAP2_ARI)) return; - pcie_capability_set_word(bridge, PCI_EXP_DEVCTL2, PCI_EXP_DEVCTL2_ARI); - bridge->ari_enabled = 1; + if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI)) { + pcie_capability_set_word(bridge, PCI_EXP_DEVCTL2, + PCI_EXP_DEVCTL2_ARI); + bridge->ari_enabled = 1; + } else { + pcie_capability_clear_word(bridge, PCI_EXP_DEVCTL2, + PCI_EXP_DEVCTL2_ARI); + bridge->ari_enabled = 0; + } } /** |