AN2797 Freescale Semiconductor / Motorola, AN2797 Datasheet - Page 9

• Manufacturer Part Number: AN2797
• Description: Migrating from IBM 750GX to MPC7447A
• Manufacturer: Freescale Semiconductor / Motorola

Both the IBM 750GX and MPC7447A offer the same common features as seen below,
Freescale Semiconductor
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128 entry, 2-way associative instruction TLB and data TLB
eight data BAT and eight instruction BAT
Translation for 4 Kbyte page size and 256 Mbyte segment size
Block sizes from 128 Kbyte to 256 Mbyte (4 Gbyte for MPC7447A)
SDR1
(32-Bit)
of Virtual Address
MMU
Upper 24-Bits
EA[0–3]
15
EA[0–19]
0
Segment Registers
SPR 25
Accesses
X
Page Table
Search Logic
(Optional)
Data
Migrating from IBM 750GX to MPC7447A, Rev. 1.0
(Optional)
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On-Chip
TLBs
Figure 5. Effective to Physical Mapping
EA[4–19]
Optional
EA[0–19]
EA[15–19]
EA[0–14]
Instruction
Accesses
EA[0–14]
PA[0–14]
PA[0–19]
EA[20–31]
EA[15–19]
PA[0–31]
DBAT0U
DBAT3U
DBAT0L
DBAT3L
IBAT0U
IBAT3U
IBAT0L
IBAT3L
X
X
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•
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PA[15–19]
PA[20–31]
BAT
Hit
Feature Overview
X
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