pci: layerscape: add a way of specifying additional iommu mappings
In the current implementation, u-boot creates iommu mappings only
for PCI devices enumarated at boot time thus does not take into
account more dynamic scenarios such as SR-IOV or PCI hot-plug.
Add an u-boot env var and a device tree property (to be used for
example in more static scenarios such as hardwired PCI endpoints
that get initialized later in the system setup) that would allow
two things:
- for a SRIOV capable PCI EP identified by its B.D.F specify
the maximum number of VFs that will ever be created for it
- for hot-plug case, specify the B.D.F with which the device
will show up on the PCI bus
More details can be found in the included documentation:
arch/arm/cpu/armv8/fsl-layerscape/doc/README.pci_iommu_extra
Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>
diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index dd1cc65..af92784 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -179,6 +179,18 @@
configured to Root Complex mode by clearing the corresponding bit of
RCW[HOST_AGT_PEX].
+config PCI_IOMMU_EXTRA_MAPPINGS
+ bool "Support for specifying extra IOMMU mappings for PCI"
+ depends on PCIE_LAYERSCAPE_RC
+ help
+ Enable support for specifying extra IOMMU mappings for PCI
+ controllers through a special env var called "pci_iommu_extra" or
+ through a device tree property named "pci-iommu-extra" placed in
+ the node describing the PCI controller.
+ The intent is to cover SR-IOV scenarios which need mappings for VFs
+ and PCI hot-plug scenarios. More documentation can be found under:
+ arch/arm/cpu/armv8/fsl-layerscape/doc/README.pci_iommu_extra
+
config PCIE_LAYERSCAPE_EP
bool "Layerscape PCIe Endpoint mode support"
depends on DM_PCI