On Arm systems, some platform devices behind an SMMU may support the PASID
feature, which offers multiple address space. Let the firmware tell us
when a device supports PASID.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
disable the IOMMU's device tree node in the first place because it would
prevent any driver from properly setting up the translations.
+Optional properties:
+--------------------
+- pasid-num-bits: Some masters support multiple address spaces for DMA, by
+ tagging DMA transactions with an address space identifier. By default,
+ this is 0, which means that the device only has one address space.
+
Notes:
======