diff options
| author | Alex Williamson <alex.williamson@redhat.com> | 2014-05-22 17:07:43 -0600 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2014-05-28 15:20:31 -0600 |
| commit | 31c2b8153c58f11ddb80dfd392c16f13c2d709c6 (patch) | |
| tree | 7ceb946ee75079ed1552f9a60e471a97bb3fa72b | |
| parent | 6b121592f8a3fd2bd0de128637b76a0d0864d993 (diff) | |
| download | linux-31c2b8153c58f11ddb80dfd392c16f13c2d709c6.tar.bz2 | |
PCI: Add support for DMA alias quirks
Some devices are broken and use a requester ID other than their physical
devfn. Add a byte, using an existing gap in the pci_dev structure, to
store an alternate "alias" devfn. A bit in the dev_flags tells us when
this is valid. We then add the alias as one more step in the
pci_for_each_dma_alias() iterator.
Tested-by: George Spelvin <linux@horizon.com>
Tested-by: Pat Erley <pat-lkml@erley.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
| -rw-r--r-- | drivers/pci/search.c | 11 | ||||
| -rw-r--r-- | include/linux/pci.h | 3 |
2 files changed, 14 insertions, 0 deletions
diff --git a/drivers/pci/search.c b/drivers/pci/search.c index 5601cdb8bbb3..2c19f3f40621 100644 --- a/drivers/pci/search.c +++ b/drivers/pci/search.c @@ -37,6 +37,17 @@ int pci_for_each_dma_alias(struct pci_dev *pdev, 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; diff --git a/include/linux/pci.h b/include/linux/pci.h index 545903df00dc..9d4035c276f4 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -171,6 +171,8 @@ enum pci_dev_flags { PCI_DEV_FLAGS_ASSIGNED = (__force pci_dev_flags_t) (1 << 2), /* Flag for quirk use to store if quirk-specific ACS is enabled */ PCI_DEV_FLAGS_ACS_ENABLED_QUIRK = (__force pci_dev_flags_t) (1 << 3), + /* Flag to indicate the device uses dma_alias_devfn */ + PCI_DEV_FLAGS_DMA_ALIAS_DEVFN = (__force pci_dev_flags_t) (1 << 4), }; enum pci_irq_reroute_variant { @@ -268,6 +270,7 @@ struct pci_dev { u8 rom_base_reg; /* which config register controls the ROM */ u8 pin; /* which interrupt pin this device uses */ u16 pcie_flags_reg; /* cached PCIe Capabilities Register */ + u8 dma_alias_devfn;/* devfn of DMA alias, if any */ struct pci_driver *driver; /* which driver has allocated this device */ u64 dma_mask; /* Mask of the bits of bus address this |