mirror of https://github.com/acidanthera/audk.git
f9d129e68a
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> Acked-by: Laszlo Ersek <lersek@redhat.com> Acked-by: Jordan Justen <jordan.l.justen@intel.com> |
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| .. | ||
| AmdSevIoMmu.c | ||
| AmdSevIoMmu.h | ||
| IoMmuDxe.c | ||
| IoMmuDxe.inf | ||