Storage Attribute Control Registers; Data Cache Write-Through Register (Dcwr); Figure 6-6. Generic Storage Attribute Control Register - IBM PowerPC 405GP User Manual

6.8.1 Storage Attribute Control Registers
Figure 6-6 shows a generic storage attribute control register. The storage attribute control registers
have the same bit numbering and address ranges.
I
0 11
I
21 31 41 51 61 71 81 91 1 0 111112113114115116117118119120 121122123124125126127128129130 1 31 1
Figure 6-6. Generic Storage Attribute Control Register
Bit Address Range
Bit
Address Range
0
OxOOOO 0000 -Ox07FF FFFF 16
Ox8000 0000 -Ox87FF FFFF
1 Ox0800 0000 -OxOFFF FFFF 17 Ox8800 0000 -Ox8FFF FFFF
2 Ox1000 0000 -Ox17FF FFFF 18 Ox9000 0000 -Ox97FF FFFF
3
Ox1800 0000 -Ox1 FFF FFFF 19 Ox9800 0000 -Ox9FFF FFFF
4 Ox2000 0000 -Ox27FF FFFF 20 OxAOOO 0000-OxA7FF FFFF
5
Ox2800 0000 -Ox2FFF FFFF 21 OxA800 0000 -OxAFFF FFFF
6
Ox3000 0000 -Ox37FF FFFF 22 OxBOOO 0000 -OxB7FF FFFF
7 Ox3800 0000 -Ox3FFF FFFF
23 OxB800 0000 -OxBFFF FFFF
8
Ox4000 0000-Ox47FF FFFF 24 OxCOOO 0000 -OxC7FF FFFF
9 Ox4800 0000 -Ox4FFF FFFF 25
OxC800 0000 -OxCFFF FFFF
10 Ox5000 0000 -Ox57FF FFFF 26
OxDOOOOOOO-OxD7FFFFFF
11 Ox5800 0000 -Ox5FFF FFFF 27 OxD800 0000 -OxDFFF FFFF
12 Ox6000 0000 -Ox67FF FFFF 28 OxEOOO 0000 -OxE7FF FFFF
13 Ox6800 0000 -Ox6FFF FFFF 29 OxE800 0000 -OxEFFF FFFF
14 Ox7000 0000 -Ox77FF FFFF 30 OxFOOO 0000 -OxF7FF FFFF
15
Ox7800 0000 -Ox7FFF FFFF 31 OxF800 0000 -OxFFFF FFFF
6.8.1.1 Data Cache Write-through Register (OCWR)
The DCWR controls write-through policy (the W storage attribute) for the data cache unit (DCU).
Write·through is not applicable to the instruction cache unit (ICU).
After any reset, all DCWR bits are set to 0, which establishes a write-back write strategy for all
regions.
The PowerPC Architecture does not support memory models in which write-through is enabled and
caching is inhibited.
6-18 PPC405GP User's Manual
Preliminary