summaryrefslogtreecommitdiffstats
path: root/drivers/pci/search.c
diff options
context:
space:
mode:
authorBjorn Helgaas <bhelgaas@google.com>2014-06-03 00:18:48 +0200
committerBjorn Helgaas <bhelgaas@google.com>2014-06-03 00:18:48 +0200
commit0eeb4f2af5f71f64ba6362df33ddc1f218075c52 (patch)
treea5ba0181900968cda030364e18235e93f975b093 /drivers/pci/search.c
parentMerge branches 'pci/host-exynos', 'pci/host-imx6', 'pci/resource' and 'pci/mi... (diff)
parentPCI: Add bridge DMA alias quirk for ASMedia and Tundra bridges (diff)
downloadlinux-0eeb4f2af5f71f64ba6362df33ddc1f218075c52.tar.xz
linux-0eeb4f2af5f71f64ba6362df33ddc1f218075c52.zip
Merge branch 'pci/iommu' into next
* pci/iommu: PCI: Add bridge DMA alias quirk for ASMedia and Tundra bridges PCI: Add support for PCIe-to-PCI bridge DMA alias quirks PCI: Add function 1 DMA alias quirk for Marvell devices PCI: Add function 0 DMA alias quirk for Ricoh devices PCI: Add support for DMA alias quirks PCI: Convert pci_dev_flags definitions to bit shifts PCI: Add DMA alias iterator
Diffstat (limited to 'drivers/pci/search.c')
-rw-r--r--drivers/pci/search.c87
1 files changed, 87 insertions, 0 deletions
diff --git a/drivers/pci/search.c b/drivers/pci/search.c
index 8e495bda678f..0e9a00e5ca60 100644
--- a/drivers/pci/search.c
+++ b/drivers/pci/search.c
@@ -17,6 +17,93 @@ DECLARE_RWSEM(pci_bus_sem);
EXPORT_SYMBOL_GPL(pci_bus_sem);
/*
+ * pci_for_each_dma_alias - Iterate over DMA aliases for a device
+ * @pdev: starting downstream device
+ * @fn: function to call for each alias
+ * @data: opaque data to pass to @fn
+ *
+ * Starting @pdev, walk up the bus calling @fn for each possible alias
+ * of @pdev at the root bus.
+ */
+int pci_for_each_dma_alias(struct pci_dev *pdev,
+ int (*fn)(struct pci_dev *pdev,
+ u16 alias, void *data), void *data)
+{
+ struct pci_bus *bus;
+ int ret;
+
+ ret = fn(pdev, PCI_DEVID(pdev->bus->number, pdev->devfn), data);
+ if (ret)
+ return ret;
+
+ /*
+ * If the device is broken and uses an alias requester ID for
+ * DMA, iterate over that too.
+ */
+ if (unlikely(pdev->dev_flags & PCI_DEV_FLAGS_DMA_ALIAS_DEVFN)) {
+ ret = fn(pdev, PCI_DEVID(pdev->bus->number,
+ pdev->dma_alias_devfn), data);
+ if (ret)
+ return ret;
+ }
+
+ for (bus = pdev->bus; !pci_is_root_bus(bus); bus = bus->parent) {
+ struct pci_dev *tmp;
+
+ /* Skip virtual buses */
+ if (!bus->self)
+ continue;
+
+ tmp = bus->self;
+
+ /*
+ * PCIe-to-PCI/X bridges alias transactions from downstream
+ * devices using the subordinate bus number (PCI Express to
+ * PCI/PCI-X Bridge Spec, rev 1.0, sec 2.3). For all cases
+ * where the upstream bus is PCI/X we alias to the bridge
+ * (there are various conditions in the previous reference
+ * where the bridge may take ownership of transactions, even
+ * when the secondary interface is PCI-X).
+ */
+ if (pci_is_pcie(tmp)) {
+ switch (pci_pcie_type(tmp)) {
+ case PCI_EXP_TYPE_ROOT_PORT:
+ case PCI_EXP_TYPE_UPSTREAM:
+ case PCI_EXP_TYPE_DOWNSTREAM:
+ continue;
+ case PCI_EXP_TYPE_PCI_BRIDGE:
+ ret = fn(tmp,
+ PCI_DEVID(tmp->subordinate->number,
+ PCI_DEVFN(0, 0)), data);
+ if (ret)
+ return ret;
+ continue;
+ case PCI_EXP_TYPE_PCIE_BRIDGE:
+ ret = fn(tmp,
+ PCI_DEVID(tmp->bus->number,
+ tmp->devfn), data);
+ if (ret)
+ return ret;
+ continue;
+ }
+ } else {
+ if (tmp->dev_flags & PCI_DEV_FLAG_PCIE_BRIDGE_ALIAS)
+ ret = fn(tmp,
+ PCI_DEVID(tmp->subordinate->number,
+ PCI_DEVFN(0, 0)), data);
+ else
+ ret = fn(tmp,
+ PCI_DEVID(tmp->bus->number,
+ tmp->devfn), data);
+ if (ret)
+ return ret;
+ }
+ }
+
+ return ret;
+}
+
+/*
* find the upstream PCIe-to-PCI bridge of a PCI device
* if the device is PCIE, return NULL
* if the device isn't connected to a PCIe bridge (that is its parent is a