Re: [PATCH v6 09/17] OvmfPkg: Add IoMmuDxe driver

[Laszlo Ersek <lersek@redhat.com>]

On 05/26/17 16:43, Brijesh Singh wrote:
> The IOMMU protocol driver provides capabilities to set a DMA access
> attribute and methods to allocate, free, map and unmap the DMA memory
> for the PCI Bus devices.
> 
> Due to security reasons all DMA operations inside the SEV guest must
> be performed on shared (i.e unencrypted) pages. The IOMMU protocol
> driver for the SEV guest uses a bounce buffer to map guest DMA buffer
> to shared pages inorder to provide the support for DMA operations inside
> SEV guest.
> 
> IoMmuDxe driver looks for SEV capabilities, if present then it installs
> the real IOMMU protocol otherwise it installs placeholder protocol.
> Currently, PciHostBridgeDxe and QemuFWCfgLib need to know the existance
> of IOMMU protocol. The modules needing to know the existance of IOMMU
> support should add
> 
>   gEdkiiIoMmuProtocolGuid OR gIoMmuAbsentProtocolGuid
> 
> in their depex to ensure that platform IOMMU detection has been performed.
> 
> 
> Cc: Jordan Justen <jordan.l.justen@intel.com>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Cc: Leo Duran <leo.duran@amd.com>
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Contributed-under: TianoCore Contribution Agreement 1.0
> Suggested-by: Jiewen Yao <jiewen.yao@intel.com>
> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
> Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
> ---
>  OvmfPkg/OvmfPkgIa32.dsc        |   1 +
>  OvmfPkg/OvmfPkgIa32X64.dsc     |   1 +
>  OvmfPkg/OvmfPkgX64.dsc         |   1 +
>  OvmfPkg/OvmfPkgIa32.fdf        |   1 +
>  OvmfPkg/OvmfPkgIa32X64.fdf     |   1 +
>  OvmfPkg/OvmfPkgX64.fdf         |   1 +
>  OvmfPkg/IoMmuDxe/IoMmuDxe.inf  |  49 +++
>  OvmfPkg/IoMmuDxe/AmdSevIoMmu.h |  43 ++
>  OvmfPkg/IoMmuDxe/AmdSevIoMmu.c | 459 ++++++++++++++++++++
>  OvmfPkg/IoMmuDxe/IoMmuDxe.c    |  53 +++
>  10 files changed, 610 insertions(+)

Looks good to me.

Acked-by: Laszlo Ersek <lersek@redhat.com>