EFI_ACPI_DMAR_DRHD_HEADER Struct Reference

Data Fields
EFI_ACPI_DMAR_STRUCTURE_HEADER	Header
UINT8	Flags
UINT8	Reserved
UINT16	SegmentNumber
UINT64	RegisterBaseAddress

Detailed Description

DMA-remapping hardware unit definition (DRHD) structure is defined in section 8.3. This uniquely represents a remapping hardware unit present in the platform. There must be at least one instance of this structure for each PCI segment in the platform.

Field Documentation

UINT8 EFI_ACPI_DMAR_DRHD_HEADER::Flags

• Bit[0]: INCLUDE_PCI_ALL
  • If Set, this remapping hardware unit has under its scope all PCI compatible devices in the specified Segment, except devices reported under the scope of other remapping hardware units for the same Segment.
  • If Clear, this remapping hardware unit has under its scope only devices in the specified Segment that are explicitly identified through the DeviceScope field.
• Bits[7:1] Reserved.

EFI_ACPI_DMAR_STRUCTURE_HEADER EFI_ACPI_DMAR_DRHD_HEADER::Header

UINT64 EFI_ACPI_DMAR_DRHD_HEADER::RegisterBaseAddress

Base address of remapping hardware register-set for this unit.

UINT8 EFI_ACPI_DMAR_DRHD_HEADER::Reserved

UINT16 EFI_ACPI_DMAR_DRHD_HEADER::SegmentNumber

The PCI Segment associated with this unit.