High Performance Two Port 10/100 Managed Ethernet Switch with 32-Bit Non-PCI CPU Interface
Datasheet
14.5.3
Switch Engine CSRs
This section details the switch engine related CSRs. These registers allow configuration and monitoring
of the various switch engine components including the ALR, VLAN, Port VID, and DIFFSERV tables.
A list of the general switch CSRs and their corresponding register numbers is included in Table 14.12.
14.5.3.1
Switch Engine ALR Command Register (SWE_ALR_CMD)
Register #:
1800h
Size:
32 bits
This register is used to manually read and write MAC addresses from/into the ALR table.
For a read access, the Switch Engine ALR Read Data 0 Register (SWE_ALR_RD_DAT_0) and Switch
Engine ALR Read Data 1 Register (SWE_ALR_RD_DAT_1) should be read following the setting of bit
1(Get First Entry) or bit 0(Get Next Entry) of this register.
For write access, the Switch Engine ALR Write Data 0 Register (SWE_ALR_WR_DAT_0) and Switch
Engine ALR Write Data 1 Register (SWE_ALR_WR_DAT_1) registers should first be written with the
MAC address, followed by the setting of bit 2(Make Entry) of this register. The Make Pending bit in the
Switch Engine ALR Command Status Register (SWE_ALR_CMD_STS) register indicates when the
command is finished.
Refer to Chapter 6, "Switch Fabric," on page 55 for more information.
BITS
DESCRIPTION
TYPE
DEFAULT
31:3
2
RESERVED
Make Entry
RO
-
R/W
0b
When set, the contents of ALR_WR_DAT_0 and ALR_WR_DAT_1 are
written into the ALR table. The ALR logic determines the location where the
entry is written. This command can also be used to change or delete a
previously written or automatically learned entry. This bit has no affect when
written low. This bit must be cleared once the ALR Make command is
completed, which can be determined by the ALR Status bit in the Switch
Engine ALR Command Status Register (SWE_ALR_CMD_STS) register.
1
0
Get First Entry
R/W
R/W
0b
0b
When set, the ALR read pointer is reset to the beginning of the ALR table
and the ALR table is searched for the first valid entry, which is loaded into
the ALR_RD_DAT_0 and ALR_RD_DAT_1 registers. The bit has no affect
when written low. This bit must be cleared after it is set.
Get Next Entry
When set, the next valid entry in the ALR MAC address table is loaded into
the ALR_RD_DAT_0 and ALR_RD_DAT_1 registers. This bit has no affect
when written low. This bit must be cleared after it is set.
SMSC LAN9312
367
Revision 1.2 (04-08-08)
DATASHEET
SMSC [ SMSC CORPORATION ]
