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| author | Yijing Wang <wangyijing@huawei.com> | 2013-01-15 11:12:16 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-02-13 11:51:17 -0800 |
| commit | d7c16d1e0a33ea79d9dc33e3f13f41b4f5caa756 (patch) | |
| tree | 94fe2dad06b41712c6f25992271551d474cf1ba8 /drivers | |
| parent | 27fb12b9e08a7f5bb8d8faa65002b9f76ee285b6 (diff) | |
| download | lwn-d7c16d1e0a33ea79d9dc33e3f13f41b4f5caa756.tar.gz lwn-d7c16d1e0a33ea79d9dc33e3f13f41b4f5caa756.zip | |
PCI: Enable ARI if dev and upstream bridge support it; disable otherwise
commit b0cc6020e1cc62f1253215f189611b34be4a83c7 upstream.
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]
[yijing: replace PCIe Cap accessor with legacy PCI accessor]
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/pci/pci.c | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index d08c0d8ec22e..a7f6dcea0d76 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1984,10 +1984,6 @@ void pci_enable_ari(struct pci_dev *dev) if (pcie_ari_disabled || !pci_is_pcie(dev) || dev->devfn) return; - pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI); - if (!pos) - return; - bridge = dev->bus->self; if (!bridge || !pci_is_pcie(bridge)) return; @@ -2006,10 +2002,14 @@ void pci_enable_ari(struct pci_dev *dev) return; pci_read_config_word(bridge, pos + PCI_EXP_DEVCTL2, &ctrl); - ctrl |= PCI_EXP_DEVCTL2_ARI; + if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI)) { + ctrl |= PCI_EXP_DEVCTL2_ARI; + bridge->ari_enabled = 1; + } else { + ctrl &= ~PCI_EXP_DEVCTL2_ARI; + bridge->ari_enabled = 0; + } pci_write_config_word(bridge, pos + PCI_EXP_DEVCTL2, ctrl); - - bridge->ari_enabled = 1; } /** |