ACPI_CSRT_DESCRIPTOR
ACPI_CSRT_DESCRIPTOR *SubSubtable;
SubSubtable = ACPI_ADD_PTR (ACPI_CSRT_DESCRIPTOR, Table,
SubSubOffset = sizeof (ACPI_CSRT_DESCRIPTOR);
SubSubtable = ACPI_ADD_PTR (ACPI_CSRT_DESCRIPTOR, SubSubtable,
sizeof (ACPI_CSRT_DESCRIPTOR));
#define ACPI_CSRT2_OFFSET(f) (UINT16) ACPI_OFFSET (ACPI_CSRT_DESCRIPTOR,f)