Add a driver to VFIO selftests for Intel DSA devices.
For now the driver only supports up to 32 batches and 1024 copies per
batch, which were the limits of the hardware this commit was tested
with. This is sufficient to generate 9+ minutes of DMA memcpys at a rate
of over 30 GB/s. This should be plenty to stress test VFIO and the IOMMU.
The driver does not yet support requesting interrupt handles, as this
commit was not tested against hardware that requires it.
Cc: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-23-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add a driver for the Intel CBDMA device. This driver is based on and
named after the Linux driver for this device (drivers/dma/ioat/) and
also based on previous work from Peter Shier <pshier@google.com>.
The driver aims to be as simple as possible. It uses a single descriptor
to issue DMA operations, and only supports the copy operation. For "DMA
storms", the driver kicks off the maximum number of maximum-sized DMA
operations. On Skylake server parts, this was 2^16-1 copies of size 2M
and lasts about 15 seconds.
Create symlinks to drivers/dma/ioat/{hw.h,registers.h} to get access to
various macros (e.g. IOAT_CHANCMD_RESET) and struct ioat_dma_descriptor.
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-20-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
