Intel
®
81341 and 81342—DDR SDRAM Memory Controller
Intel
®
81341 and 81342 I/O Processors
Developer’s Manual
December 2007
648
Order Number: 315037-002US
7.8.21
DMCU Port Transaction Count Register — DMPTCR
Sets the number of transactions a given port has processed during a single tenure. The
4-bit fields for each port allow up to 16 transactions to be processed by a port before
the DMCU arbiter selects a different port for DDR SDRAM transactions. This register
“DMCU Preemption Control Register — DMPCR” on page 650
are used to
optimize the memory controller operation.
Table 394. DMCU Port Transaction Count Register — DMPTCR (Sheet 1 of 2)
Bit
Default
Description
31:24
00H
Reserved
23:20 1H
MU Port Transaction Count: Number of transactions the MU port can have processed in a single
tenure of the DDR SDRAM.
1H = 1 transaction
2H = 2 transactions
3H = 3 transactions
...
FH = 15 transactions
0H = 16 transactions
Note:
The MU Port Transaction Count is always set to 1H.
19:16 1H
ADMA 2 Port Transaction Count: Number of transactions the ADMA 2 port can have processed in a
single tenure of the DDR SDRAM.
1H = 1 transaction
2H = 2 transactions
3H = 3 transactions
...
FH = 15 transactions
0H = 16 transactions
15:12 1H
ADMA 1 Port Transaction Count: Number of transactions the ADMA 1 port can have processed in a
single tenure of the DDR SDRAM.
1H = 1 transaction
2H = 2 transactions
3H = 3 transactions
...
FH = 15 transactions
0H = 16 transactions
PCI
IOP
Attributes
Attributes
28
24
20
16
12
8
4
0
31
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
ro
na
ro
na
ro
na
ro
na
rw
na
rw
na
rw
na
rw
na
rw
na
rw
na
rw
na
rw
na
rw
na
rw
na
rw
na
rw
na
rw
na
rw
na
rw
na
rw
na
rw
na
rw
na
rw
na
rw
na
Attribute Legend:
RV = Reserved
PR = Preserved
RS = Read/Set
RW = Read/Write
RC = Read Clear
RO = Read Only
NA = Not Accessible
Intel XScale
®
microarchitecture Local Bus
Address offset
+1868H