Re: [Qemu-devel] [V9 4/4] hw/pci-host: Emulate AMD IOMMU

[Peter Xu <peterx@redhat.com>]

On Mon, Apr 25, 2016 at 01:12:57AM +0300, David Kiarie wrote:
> Add AMD IOMMU emulation support to q35 chipset
> 
> Signed-off-by: David Kiarie <davidkiarie4@gmail.com>
> ---
>  hw/pci-host/q35.c             | 21 +++++++++++++++++++--
>  include/hw/i386/intel_iommu.h |  2 +-
>  2 files changed, 20 insertions(+), 3 deletions(-)
> 
> diff --git a/hw/pci-host/q35.c b/hw/pci-host/q35.c
> index 70f897e..37f8a84 100644
> --- a/hw/pci-host/q35.c
> +++ b/hw/pci-host/q35.c
> @@ -32,6 +32,7 @@
>  #include "hw/pci-host/q35.h"
>  #include "qapi/error.h"
>  #include "qapi/visitor.h"
> +#include "hw/i386/amd_iommu.h"
>  
>  /****************************************************************************
>   * Q35 host
> @@ -448,6 +449,19 @@ static void mch_init_dmar(MCHPCIState *mch)
>      pci_setup_iommu(pci_bus, q35_host_dma_iommu, mch->iommu);
>  }
>  
> +static void mch_init_amdvi(MCHPCIState *mch)
> +{
> +    AMDIOMMUState *iommu_state;
> +    PCIBus *bus = PCI_BUS(qdev_get_parent_bus(DEVICE(mch)));
> +    PCIDevice *iommu;
> +
> +    iommu = pci_create_simple(bus, 0x20, TYPE_AMD_IOMMU_DEVICE);
> +
> +    iommu_state = AMD_IOMMU_DEVICE(iommu);
> +
> +    pci_setup_iommu(bus, bridge_host_amd_iommu, iommu_state);
> +}
> +
>  static void mch_realize(PCIDevice *d, Error **errp)
>  {
>      int i;
> @@ -506,8 +520,11 @@ static void mch_realize(PCIDevice *d, Error **errp)
>                   mch->pci_address_space, &mch->pam_regions[i+1],
>                   PAM_EXPAN_BASE + i * PAM_EXPAN_SIZE, PAM_EXPAN_SIZE);
>      }
> -    /* Intel IOMMU (VT-d) */
> -    if (object_property_get_bool(qdev_get_machine(), "iommu", NULL)) {
> +
> +    if (object_property_get_bool(qdev_get_machine(), "iommu", NULL) &&
> +        MACHINE(qdev_get_machine())->x_iommu_type) {
> +        mch_init_amdvi(mch);
> +    } else if (object_property_get_bool(qdev_get_machine(), "iommu", NULL)) {
>          mch_init_dmar(mch);
>      }

Like patch 3's comment, I would prefer this:

    if (object_property_get_bool(qdev_get_machine(), "iommu", NULL)) {
        if (MACHINE(qdev_get_machine())->x_iommu_type) {
            mch_init_amdvi(mch);
        } else {
            mch_init_dmar(mch);
        }
    }

Thanks.

-- peterx