Add a basic implementation of the ARM SMMU. This driver is intended for
use on Qualcomm platforms where the SMMU has been configured by a previous
bootloader, cannot be turned off, and doesn't support BYPASS streams.
It keeps all existing stream mappings and only creates new ones for stream
ids that aren't already configured.
This driver is necessary to support peripherals that perform DMA which
weren't configured by the previous stage bootloader (for example USB).
It works by allocating a context bank using identity mapping (as U-Boot
doesn't use virtual addresses).
Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>
The DART is an IOMMU that is used on Apple's M1 SoC. This driver
configures the DART such that it operates in bypass mode which is
enough to support DMA for the USB3 ports integrated on the SoC.
Signed-off-by: Mark Kettenis <kettenis@openbsd.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
This uclass is intended to manage IOMMUs on systems where the
IOMMUs are not in bypass mode by default. In that case U-Boot
cannot ignore the IOMMUs if it wants to use devices that need
to do DMA and sit behind such an IOMMU.
This initial IOMMU uclass implementation does not implement and
device ops and is intended for IOMMUs that have a bypass mode
that does not require address translation. Support for IOMMUs
that do require address translation is planned and device ops
will be defined when support for such IOMMUs will be added.
Signed-off-by: Mark Kettenis <kettenis@openbsd.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
