Receive Data and Receive BD Initiator Control Registers
BCM5718 Programmer’s Guide
Broadcom
®
January 29, 2016 • 5718-PG108-R
Page 367
Receive Producer Ring Host Address Low Register (offset: 0x2454)
Receive Producer Length/Flags Register (offset: 0x2458)
Receive Producer Ring NIC Address Register (offset: 0x245C)
Receive Diagnostic Data and Receive BD Ring Initiator Local NIC
Jumbo Receive BD Consumer Index (offset: 0x2470)
This set of registers keeps track of the current DMAs queued to move receive data from the controller to the
host. The receive data and receive BD initiator maintains the state of the indices by keeping two local copies, a
copy of the controller's return ring producer index and a copy of the controller's receive BD consumer index.
The local return ring producer index is set to the value placed in the DMA descriptor. The local controller receive
return consumer index is also set to the value placed in the DMA descriptor.
Name
Bits
Access
Default
Value
Description
Host Address Low
31:0
RW
0
The host ring address is the host address of the first
ring element. The host ring address is in host
address format.
Name
Bits
Access
Default
Value
Description
Max Length
31:16
RW
0
Programmable ring size:
• 2048
• 1024
• 512
• 256
• 128
• 64
• 32
Reserved
15:2
RO
0
Maximum RX frame size.
Disable Ring
1
RW
0
1 = Ring Disabled
0 = Ring Enabled
Reserved
0
RO
0
Reserved
Name
Bits
Access
Default
Value
Description
NIC Address
31:0
RW
0x000400
00
The NIC ring address is the NIC address of the first
ring element.
Note:
For the BCM5718 family, do not initialize this
register; leave as default.