PowerPC e500 Core Family Reference Manual, Rev. 1
Freescale Semiconductor
xi
Contents
Paragraph
Number
Title
Page
Number
Chapter 4
Execution Timing
4.1
Terminology and Conventions ......................................................................................... 4-1
4.2
Instruction Timing Overview........................................................................................... 4-4
4.3
General Timing Considerations ..................................................................................... 4-10
4.3.1
General Instruction Flow ........................................................................................... 4-11
4.3.2
Instruction Fetch Timing Considerations................................................................... 4-12
4.3.2.1
L1 and L2 TLB Access Times ............................................................................... 4-12
4.3.2.2
Interrupts Associated with Instruction Fetching.................................................... 4-12
4.3.2.3
Cache-Related Latency .......................................................................................... 4-13
4.3.3
Dispatch, Issue, and Completion Considerations ...................................................... 4-14
4.3.3.1
GPR and CR Rename Register Operation ............................................................. 4-15
4.3.3.2
LR and CTR Shadow (Speculative) Registers....................................................... 4-15
4.3.3.3
Instruction Serialization......................................................................................... 4-15
4.3.4
Interrupt Latency........................................................................................................ 4-16
4.3.5
Memory Synchronization Timing Considerations..................................................... 4-17
4.3.5.1
msync Instruction Timing Considerations ............................................................ 4-17
4.3.5.2
mbar Instruction Timing Considerations .............................................................. 4-17
4.4
Execution ....................................................................................................................... 4-18
4.4.1
Branch Unit Execution............................................................................................... 4-18
4.4.1.1
Branch Instructions and Completion ..................................................................... 4-18
4.4.1.2
BTB Branch Prediction and Resolution ................................................................ 4-20
4.4.1.3
BTB Operations ..................................................................................................... 4-21
4.4.1.3.1
BTB Locking ..................................................................................................... 4-23
4.4.1.3.2
BTB Locking APU Programming Model.......................................................... 4-24
4.4.1.3.3
BTB Operations Controlled by BUCSR............................................................ 4-24
4.4.1.3.4
BTB Special Cases—Phantom Branches and Multiple Matches ...................... 4-25
4.4.2
Load/Store Unit Execution ........................................................................................ 4-25
4.4.2.1
Load/Store Unit Queueing Structures.................................................................... 4-25
4.4.3
Simple and Multiple Unit Execution ......................................................................... 4-27
4.4.3.1
MU Divide Execution............................................................................................ 4-28
4.4.3.2
MU Floating-Point Execution................................................................................ 4-29
4.4.4
Load/Store Execution ................................................................................................ 4-29
4.4.4.1
Effect of Operand Placement on Performance ...................................................... 4-30
4.5
Memory Performance Considerations ........................................................................... 4-30
4.6
Instruction Latency Summary........................................................................................ 4-31
Summary of Contents for PowerPC e500 Core
Page 1: ...PowerPC e500 Core Family Reference Manual Supports e500v1 e500v2 E500CORERM Rev 1 4 2005...
Page 36: ...PowerPC e500 Core Family Reference Manual Rev 1 xxxvi Freescale Semiconductor...
Page 38: ...PowerPC e500 Core Family Reference Manual Rev 1 Part I 2 Freescale Semiconductor...
Page 332: ...PowerPC e500 Core Family Reference Manual Rev 1 Part II 2 Freescale Semiconductor...
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