Intel PXA270 Optimization Manual page 7

6.2.2.6
6.2.3 Wireless Intel Speedstep® Technology Power Manager .....................................6-3
6.2.4 System Bus Frequency Selection .........................................................................6-3
6.2.4.1
6.2.4.2
6.3 Optimizations for Memory and Peripheral Power ..............................................................6-5
6.3.1 Improved Caching and Internal Memory Usage ...................................................6-5
6.3.2 SDRAM Auto Power Down (APD) ........................................................................6-5
6.3.3 External Memory Bus Buffer Strength Registers ..................................................6-5
6.3.4 Peripheral Clock Gating ........................................................................................6-5
6.3.5 LCD Subsystem ....................................................................................................6-5
6.3.6 Voltage and Regulators ........................................................................................6-6
6.3.7 Operating Mode Recommendations for Power Savings .......................................6-6
6.3.7.1
6.3.7.2
6.3.7.3
6.3.7.4
6.3.7.5
6.3.7.6
A Performance Checklist.............................................................................................................. A-1
A.1 Performance Optimization Tips ........................................................................................ A-1
A.2 Power Optimization Guidelines......................................................................................... A-2
Glossary ................................................................................................................................... Glossary-1
Figures
1-1 PXA27x Processor Block Diagram ............................................................................................1-3
2-1 Intel XScale® Microarchitecture RISC Superpipeline................................................................2-1
2-2 Intel® Wireless MMX™ Technology Pipeline Threads and relation with Intel XScale®
Microarchitecture Pipeline .........................................................................................................2-7
4-1 High-Level Pipeline Organization ............................................................................................4-46
Tables
1-1 Related Documentation .............................................................................................................1-1
2-1 Pipelines and Pipe Stages.........................................................................................................2-2
3-1 External SDRAM Access Latency and Throughput for Different Frequencies (Silicon
Measurement Pending) .............................................................................................................3-1
3-2 Internal SRAM Access Latency and Throughput for Different Frequencies (Silicon
Measurement Pending) .............................................................................................................3-2
3-3 Data Cache and Buffer Behavior when X = 0 ............................................................................3-3
3-4 Data Cache and Buffer Behavior when X = 1 ............................................................................3-3
3-5 Data Cache and Buffer operation comparison for Intel® SA-1110 and Intel XScale®
Microarchitecture, X=0...............................................................................................................3-4
3-6 Sample LCD Configurations with Latency and Peak Bandwidth Requirements......................3-13
3-7 Memory to Memory Performance Using DMA for Different Memories and Frequencies.........3-17
4-1 PXA27x processor Mapping to Intel® Wireless MMX™ Technology and SSE .......................4-27
Intel® PXA27x Processor Family Optimization Guide
Deep-Sleep Mode .................................................................................6-2
Fast-Bus Mode......................................................................................6-4
Half-Turbo Mode ...................................................................................6-4
Normal Mode ........................................................................................6-6
Idle Mode ..............................................................................................6-6
Deep-Idle Mode ....................................................................................6-7
Standby Mode .......................................................................................6-7
Sleep Mode ...........................................................................................6-7
Deep-Sleep Mode .................................................................................6-7
Contents
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