Instruction Cache Read - Motorola MPC823e Reference Manual

Instruction Cache

9.4.6 Instruction Cache Read

The MPC823e allows you to read all data stored in the instruction cache, including the
content of the tags array. However, this operation is privileged and any attempt to perform
it when the core is in the problem state (MSR
the data stored in the instruction cache, follow these steps:
1. Write the address of the data to be read to the IC_ADR. It is also possible to read this
register for debugging purposes.
2. Read the IC_DAT register.
So that it can access all parts of the instruction cache, the IC_ADR is divided into the fields
shown in the following table.
IC_ADR (CACHE READ COMMAND FORMAT)
BIT 0 1 2
FIELD
RESET
R/W
SPR
BIT 16 17 18
FIELD RES TS WAY
RESET — — —
R/W R/W R/W R/W
SPR
NOTE: — = Undefined.
Bits 0–16—Reserved
These bits are reserved and must be set to 0.
TD—Tag or Data Select
0 = Select tag RAM.
1 = Select data RAM.
WAY—Way Select
00 = Select way 0 of cache array.
01 = Select way 1 of cache array.
10 = Select way 2 of cache array.
11 = Select way 3 of cache array.
SET—Set Select
This field is used to select the set index of the cache array.
9-12
=1) results in a program interrupt. To read
PR
3 4 5 6 7
RESERVED
—
R/W
561
19 20 21 22 23
SET
—
R/W
561
MPC823e REFERENCE MANUAL
8 9 10 11 12
24 25 26 27 28
WORD
—
R/W
13 14 15
29 30 31
RESERVED
—
R/W
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