Intel Extensible Firmware Interface User Manual
Page 17

Contents
Version 1.10
12/01/02
xvii
17.4
Decompressor Design..................................................................................... 17-15
17.5
Decompress Protocol...................................................................................... 17-16
EFI_DECOMPRESS_PROTOCOL .............................................................. 17-16
EFI_DECOMPRESS_PROTOCOL.GetInfo() ............................................. 17-17
EFI_DECOMPRESS_PROTOCOL.Decompress()..................................... 17-19
18 Protocols — Device I/O Protocol
18.1
Device I/O Overview ......................................................................................... 18-1
18.2
DEVICE_IO Protocol......................................................................................... 18-2
DEVICE_IO Protocol...................................................................................... 18-2
DEVICE_IO.Mem(), .Io(), and .Pci() ............................................................. 18-5
DEVICE_IO.PciDevicePath() ....................................................................... 18-7
DEVICE_IO.Map() ....................................................................................... 18-8
DEVICE_IO.Unmap()................................................................................. 18-10
DEVICE_IO.AllocateBuffer() ...................................................................... 18-11
DEVICE_IO.Flush() ................................................................................... 18-13
DEVICE_IO.FreeBuffer() ........................................................................... 18-14
19 EFI Byte Code Virtual Machine
19.1
Overview........................................................................................................... 19-1
19.1.1
Processor Architecture Independence...................................................... 19-1
19.1.2
OS Independent ....................................................................................... 19-2
19.1.3
EFI Compliant .......................................................................................... 19-2
19.1.4
Coexistence of Legacy Option ROMs....................................................... 19-2
19.1.5
Relocatable Image ................................................................................... 19-2
19.1.6
Size Restrictions Based on Memory Available.......................................... 19-3
19.2
Memory Ordering .............................................................................................. 19-3
19.3
Virtual Machine Registers ................................................................................. 19-3
19.4
Natural Indexing................................................................................................ 19-5
19.4.1
Sign Bit..................................................................................................... 19-5
19.4.2
Bits Assigned to Natural Units .................................................................. 19-6
19.4.3
Constant................................................................................................... 19-6
19.4.4
Natural Units ............................................................................................ 19-6
19.5
EBC Instruction Operands ................................................................................ 19-7
19.5.1
Direct Operands ....................................................................................... 19-7
19.5.2
Indirect Operands..................................................................................... 19-7
19.5.3
Indirect with Index Operands .................................................................... 19-8
19.5.4
Immediate Operands................................................................................ 19-8
19.6
EBC Instruction Syntax ..................................................................................... 19-9
19.7
Instruction Encoding ......................................................................................... 19-9
19.7.1
Instruction Opcode Byte Encoding ......................................................... 19-10
19.7.2
Instruction Operands Byte Encoding ...................................................... 19-10
19.7.3
Index/Immediate Data Encoding............................................................. 19-11
19.8
EBC Instruction Set......................................................................................... 19-11
ADD........................................................................................................... 19-12
AND........................................................................................................... 19-13
ASHR ........................................................................................................ 19-14
BREAK ...................................................................................................... 19-15