A–14
System Address Space
21164 Byte/Word PCI Space
Table 1–3 shows noncached 21164 addresses when byte/word support is enabled.
A.4.1 21164 Size Field
Table A–4 shows the calculation of the 21164 size field.
The following transactions use single data transfers on the PCI:
•
INT1 and INT2 read and write transactions
•
INT4 read transactions
The following transactions have multiple data transfers on the PCI:
•
INT4 write transactions
•
INT8 read and write transactions
Table A–3 21164 Byte/Word Addressing
Instruction
addr_h
<38:37>
int4_valid
<3>
<2>
<1>
<0>
LDQ
00
INT8
—
—
—
LDL
01
addr_h<3:2>
—
Undefined
—
LDWU
10
addr_h<3:1>
—
—
Undefined
LDBU
11
addr_h<3:0>
—
—
—
STQ
00
INT4 Mask
—
—
—
STL
01
INT4 Mask
—
—
—
STW
10
addr_h<3:1>
—
—
Undefined
STB
11
addr_h<3:0>
—
—
—
Table A–4 21164 Byte/Word Translation Values
Size<38:37>
Data Size
00
INT8 (Quadword — 8 bytes, 64 bits)
01
INT4 (Longword — 4 bytes, 32 bits)
10
INT2 (Word — 2 bytes, 16 bits)
11
INT1 (Byte — 1 byte, 8 bits)