On Mon, Sep 30, 2013 at 05:28:36PM +0200, Antonios Motakis wrote: > This is a preview of the base work, towards VFIO support on ARM platforms > with an IOMMU. It forms a base on to which to implement the functionality > necessary to enable using device tree devices on ARM (and other platforms > based on device trees) with VFIO. > > This patch series has been subjected to limited testing on the Arndale board > (with the Exynos 5250 System MMU). More extensive testing will follow as more > features are implemented. Which device did you access behind the system MMU? I seem to recall someone telling me that only the GPU is behind the system MMU on Arndale. > > It depends on Cho KyongHo's patch series "iommu/exynos: Fixes and Enhancements > of System MMU driver with DT", applied on a Linux 3.10.1 kernel, and also my > own "iommu/exynos: add devices attached to the System MMU to an IOMMU group". > Those patches are required at least in order to test the proposed module on > Arndale. > > The API used is identical to the existing VFIO API that is also used with > PCI devices. Only devices that include a basic set of IRQs and memory regions > are targeted; devices with complicated relationships with other devices on the > device tree are not taken into account at this stage. > > The following IOCTLs have been found to be working on the Arndale with no > changes to VFIO: > - VFIO_GET_API_VERSION > - VFIO_CHECK_EXTENSION > The TYPE1 fix proposed here enables the following IOCTLs: > - VFIO_GROUP_GET_STATUS > - VFIO_GROUP_SET_CONTAINER > - VFIO_SET_IOMMU > - VFIO_IOMMU_GET_INFO > - VFIO_IOMMU_MAP_DMA > The VFIO platform driver proposed here implements the following: > - VFIO_GROUP_GET_DEVICE_FD > - VFIO_DEVICE_GET_INFO > - VFIO_DEVICE_GET_REGION_INFO > - VFIO_DEVICE_GET_IRQ_INFO > In addition, the VFIO platform driver implements the following through > the VFIO device file descriptor: > - MMAPing memory regions to the virtual address space of the VFIO user. > - Read / write of memory regions directly through the file descriptor. > > What still needs to be done, includes: > - IRQs / IRQFD support. > - The API is not currently extended with device tree specific information. > - Proper binding of the VFIO_DT driver to devices; currently to test the > driver, one has to edit the device tree and add "vfio" to the > compatible property. However Linux does not support OF drivers that > can be dynamically bound to any device. > - More extensive testing with a functioning device doing DMA. > - QEMU / KVM support. > > Antonios Motakis (7): > VFIO_IOMMU_TYPE1 workaround to build for platform devices > Initial skeleton of VFIO support for Device Tree based devices > Return info for device and its memory regions and interrupts > VFIO: DT: Support MMAP of MMIO regions > VFIO: DT: Read and write support for the device fd > VFIO: Update documentation for VFIO_IOMMU_TYPE1 driver > VFIO: VFIO_PLATFORM: Update documentation for platform specific > devices > > Documentation/vfio.txt | 25 +++- > drivers/vfio/Kconfig | 13 +- > drivers/vfio/Makefile | 1 + > drivers/vfio/vfio_iommu_type1.c | 22 ++- > drivers/vfio/vfio_platform.c | 308 ++++++++++++++++++++++++++++++++++++++++ > include/uapi/linux/vfio.h | 1 + > 6 files changed, 361 insertions(+), 9 deletions(-) > create mode 100644 drivers/vfio/vfio_platform.c > > -- > 1.8.1.2 > > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Christoffer -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
