struct nbft_header - NBFT Table - Header (Figure 8)
struct nbft_header {
char signature[4];
__le32 length;
__u8 major_revision;
__u8 checksum;
char oem_id[6];
char oem_table_id[8];
__le32 oem_revision;
__le32 creator_id;
__le32 creator_revision;
__le32 heap_offset;
__le32 heap_length;
struct nbft_heap_obj driver_dev_path_sig;
__u8 minor_revision;
__u8 reserved[13];
};
- signature
- Signature: An ASCII string representation of the table identifier. This
field shall be set to the value 4E424654h (i.e. "NBFT", see
#NBFT_HEADER_SIG).
- length
- Length: The length of the table, in bytes, including the header, starting
from offset 0h. This field is used to record the size of the entire
table.
- major_revision
- Major Revision: The major revision of the structure corresponding to the
Signature field. Larger major revision numbers should not be assumed
backward compatible to lower major revision numbers with the same
signature.
- checksum
- Checksum: The entire table, including the Checksum field, shall sum to 0h
to be considered valid.
- oem_id
- OEMID shall be populated by the NBFT driver writer by an OEM-supplied
string that identifies the OEM. All trailing bytes shall be NULL.
- oem_table_id
- OEM Table ID: This field shall be populated by the NBFT driver writer with
an OEM-supplied string that the OEM uses to identify the particular data
table. This field is particularly useful when defining a definition block
to distinguish definition block functions. The OEM assigns each dissimilar
table a new OEM Table ID.
- oem_revision
- OEM Revision: An OEM-supplied revision number. Larger numbers are assumed
to be newer revisions.
- creator_id
- Creator ID: Vendor ID of utility that created the table. For instance,
this may be the ID for the ASL Compiler.
- creator_revision
- Creator Revision: Revision of utility that created the table. For
instance, this may be the ID for the ASL Compiler.
- heap_offset
- Heap Offset (HO): This field indicates the offset in bytes of the heap, if
any, from byte offset 0h of the NBFT Table Header.
- heap_length
- Heap Length (HL): The length of the heap, if any.
- driver_dev_path_sig
- Driver Signature Heap Object Reference: This field indicates the offset in
bytes of a heap object containing the Driver Signature, if any, from byte
offset 0h of the NBFT Table Header.
- minor_revision
- Minor Revision: The minor revision of the structure corresponding to the
Signature field. If the major revision numbers are the same, any minor
revision number differences shall be backwards compatible with the same
signature.
- reserved
- Reserved.