
Instruction Model
e200z3 Power Architecture Core Reference Manual, Rev. 2
Freescale Semiconductor
3-3
3.4 Implementation-Specific Instructions
Book E defines some instructions that are implementation specific.
summarizes the e200z3
implementation-specific instructions.
3.5 BookE Instruction Extensions
The variable length encoding (VLE) provides an extension to 32-bit PowerPC Book E. There are
additional operations defined using an alternate instruction encoding to enable reduced code footprint.
This alternate encoding set is selected on an instruction page basis. A single page attribute bit selects
between standard PowerPC Book E instruction encodings and VLE instructions for that page of memory.
This page attribute is an extension to the PowerPC Book E page attributes. Pages can be freely intermixed,
allowing for a mixture of code using both types of encodings.
Instruction encodings in pages marked as using the VLE extension are either 16 or 32 bits long, and are
aligned on 16-bit boundaries. Therefore, all instruction pages marked as VLE are required to use
big-endian byte ordering.
This section describes the various extensions to Book E instructions to support the VLE extension.
Table 3-2. List of Optionally Supported Instructions
Type/Name
Mnemonics
Unit
Cache management instructions
dcba, dcbf, dcbi, dcbt, dcbtst, dcbst, dcbz
icbi, icbt
Data cache/unified cache
Instruction cache/unified cache
Cache locking instructions
dcbtls, dcbtstls, dcblc
icbtls, icblc
Data cache/unified cache
Instruction cache/unified cache
TLB management instructions
tlbivax, tlbre, tlbsx, tlbsync, tlbwe
TLB
DCR management
mfdcr, mtdcr
DCR
Table 3-3. Implementation-Specific Instruction Summary
Mnemonic
Implementation Details
mfapidi
Unimplemented instructions
mfdcrx
,
mtdcrx
stwcx.
Address match with prior
lwarx
not required for store to be performed
mfdcr
,
mtdcr
1
1
The e200z3 CPU takes an illegal instruction interrupt for unsupported DCR values
Optionally supported instructions
tlbivax
tlbre
tlbsx
tlbsync
tlbwe