User`s guide

Other register fields that are unnamed may be labeled as specified in Table 2.
Table 2 Unnamed Register Field Notation
Notation Description
0 A 0 in a bit position indicates a register bit that is read as a 0 and is
ignored on a write transaction.
1 A 1 in a bit position indicates a register bit that is read as a 1 and is
ignored on a write transaction.
x An x in a bit position indicates a register bit that does not exist in
hardware. The value is UNPREDICTABLE when read, and is ignored
on a write transaction.
Bit Notation
Multiple bit fields are shown as extents (see Ranges and Extents).
Cautions
Cautions indicate potential damage to equipment or data.
Data Units
Table 3 defines the data unit terminology used in this guide.
Table 3 Data Units
Term Words Bytes Bits Other
Word 1 2 16 —
Longword 2 4 32 —
Quadword 4 8 64 —
Octaword 8 16 128 Single read fill; that is, the cache space
that can be filled in a single read access.
It takes two read accesses to fill one L2
cache line (see Hexword).
Hexword 16 32 256 Cache block, cache line. The space
allocated to a single cache block.
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