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>
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 545903d..9d4035c 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -171,6 +171,8 @@
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 @@
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