ping
On 5/23/2017 2:12 PM, Diana Craciun wrote:
> The NXP DPAA2 is a hardware architecture designed for high-speeed network
> packet processing. The DPAA2 hardware components are managed by a hardware
> component called the Management Complex (or MC) which provides an
> object-base abstraction for software drivers to use the DPAA2 hardware.
> For more details you can see:
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/staging/fsl-mc/README.txt?h=v4.10
>
> The interrupts generated by the DPAA2 hardware components are MSIs. We will
> add
> support for direct assigning these DPAA2 components/objects to a virtual
> machine. However, this will add the need to expand the MSI usage in QEMU.
>
> Currently the MSIs in QEMU are pretty much tied to PCI. For ARM the
> GIC ITS is using a device ID for interrupt translation. Currently, for
> PCI, the requester ID is used as device ID. This will not work when
> we add another entity that needs also a device ID which is supposed to
> be unique across the system.
>
> My proposal is to add a static allocation in the virt machine. I considered
> that this allocation is specific to each machine/platform. Currently only
> virt machine has it, but other implementations may use the same mechanism
> as well.
> So, I used a static allocation with this formula:
>
> DeviceID = zero_extend( RequesterID[15:0] ) + 0x10000 * Constant
>
> This formula was taken from SBSA spec (Appendix I: DeviceID generation and
> ITS groups). In case of QEMU the constant will be different for each entity.
> In this way a unique DeviceID will be generated and the device ID will be
> derived from a requesterID (in case of PCI) or other means in case of other
> entities.
>
> The implementation is generic as there might be in the future other non-pci
> devices
> that are using MSIs or IOMMU. Any architecture can use it, though currently
> only the ARM architecture is using the function that retrieves the stream ID.
> I
> did not change all the replacements of the pci_requester_id (with
> pci_stream_id)
> in the code (although if the constant is 0, the stream_id is equal with
> requester_id).
> The other architectures (e.g. intel iommu code) assume that the ID is the
> requester ID.
>
> Tested on NXP LS2080 platform.
>
> History:
>
> v1->v2
> ------
> - the stream ID was added as a field in the pci device structure in order
> not to traverse the PCI hierarchy each time a MSI is sent.
>
>
> Diana Craciun (2):
> Increased the size of requester_id field from MemTxAttrs
> Add a unique ID in the virt machine to be used as device ID
>
> hw/arm/virt.c | 26 ++++++++++++++++++++++++++
> hw/i386/amd_iommu.c | 2 +-
> hw/i386/intel_iommu.c | 2 +-
> hw/intc/arm_gicv3_its_common.c | 2 +-
> hw/intc/arm_gicv3_its_kvm.c | 2 +-
> hw/pci-host/gpex.c | 6 ++++++
> hw/pci/msi.c | 2 +-
> hw/pci/pci.c | 25 +++++++++++++++++++++++++
> include/exec/memattrs.h | 4 ++--
> include/hw/arm/virt.h | 1 +
> include/hw/intc/arm_gicv3_its_common.h | 2 +-
> include/hw/pci-host/gpex.h | 2 ++
> include/hw/pci/pci.h | 8 ++++++++
> kvm-all.c | 4 ++--
> 14 files changed, 78 insertions(+), 10 deletions(-)
>
