IBM 750GL, 750GX List of Figures, List of Tables, About This Manual, 1. PowerPC 750GX Overview

	User’s Manual
IBM PowerPC 750GX and 750GL RISC Microprocessor
List of Figures ..............................................................................................................	13
List of Tables ...............................................................................................................	. 15
About This Manual ........................................................................................................	19
Who Should Read This Manual ...................................................................................................	......... 19
Related Publications .............................................................................................................................	19
Conventions Used in This Manual ...............................................................................................	......... 20
Using This Manual with the Programming Environments Manual .........................................................	22
1. PowerPC 750GX Overview .......................................................................................	23
1.1 750GX Microprocessor Overview .............................................................................................	...... 23
1.2 750GX Microprocessor Features .............................................................................................	....... 25
1.2.1 Instruction Flow ........................................................................................................	............. 29
1.2.1.1 Instruction Queue and Dispatch Unit ..............................................................................	29
1.2.1.2 Branch Processing Unit (BPU) .......................................................................................	29
1.2.1.3 Completion Unit .......................................................................................................	....... 30
1.2.2 Independent Execution Units .............................................................................................	.... 31
1.2.2.1 Integer Units (IUs) ...................................................................................................	....... 31
1.2.2.2 Floating-Point Unit (FPU) .............................................................................................	.. 31
1.2.2.3 Load/Store Unit (LSU) .................................................................................................	... 32
1.2.2.4 System Register Unit (SRU) ...........................................................................................	32
1.2.3 Memory Management Units (MMUs) .....................................................................................	32
1.2.4 On-Chip Level 1 Instruction and Data Caches ......................................................................	33
1.2.5 On-Chip Level 2 Cache Implementation ................................................................................	35
1.2.6 System Interface/Bus Interface Unit (BIU) .............................................................................	35
1.2.7 Signals ...................................................................................................................................	37
1.2.8 Signal Configuration ....................................................................................................	.......... 38
1.2.9 Clocking .................................................................................................................................	40
1.3 750GX Microprocessor Implementation .......................................................................................	... 40
1.4 PowerPC Registers and Programming Model ................................................................................	42
1.5 Instruction Set .................................................................................................................................	45
1.5.1 PowerPC Instruction Set .................................................................................................	...... 45
1.5.2 750GX Microprocessor Instruction Set ..................................................................................	47
1.6 On-Chip Cache Implementation ..............................................................................................	........ 47
1.6.1 PowerPC Cache Model .....................................................................................................	.... 47
1.6.2 750GX Microprocessor Cache Implementation ....................................................................	47
1.7 Exception Model ..............................................................................................................................	48
1.7.1 PowerPC Exception Model .................................................................................................	... 48
1.7.2 750GX Microprocessor Exception Implementation ...............................................................	49
1.8 Memory Management .........................................................................................................	............ 51
1.8.1 PowerPC Memory-Management Model ................................................................................	51
1.8.2 750GX Microprocessor Memory-Management Implementation ...........................................	52
1.9 Instruction Timing ............................................................................................................................	52
1.10 Power Management .........................................................................................................	............. 54
1.11 Thermal Management .......................................................................................................	............ 55
1.12 Performance Monitor .....................................................................................................................	56
750gx_umTOC.fm.(1.2)
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