Broadcom NetXtreme/NetLink BCM5718 Series User Manual

Receive Data PathBCM5718 Programmer’s Guide
Broadcom®
January 29, 2016 • 5718-PG108-R Page 54
Receive Data Path
RX Engine
The receive engine (see Figure 3) activates whenever a packet arrives from the PHY.
Figure 3: Receive Data Path
The receive engine performs the following four functions:
• Moves the data from the PHY to an internal FIFO
• Moves the data from the FIFO to NIC internal memory
• Classifies the frame and checks it for rules matches
• Performs the offloaded checksum calculations
RX FIFO
The RX FIFO provides elasticity while data is read from PHY transceiver and written into internal memory. There
are no programmable settings for the RX FIFO. This FIFO’s operation is completely transparent to host
software.
RX
Engine
Rules Checker
Rx
FIFO
Frame
Buffers
Empty BD
NIC Standard RX Producer Ring
Host RX
Return
Ring
List
Initiator
Rx Return BD Rx Return BD Rx Return BD Rx Return BD Rx Return BD
Host Standard RX Producer
Ring
DMA
DMA
Full BD
Empty BD
NIC Jumbo RX Producer Ring
DMA
Host Jumbo RX Producer Ring

Broadcom NetXtreme/NetLink BCM5718 Series Specifications

General

Brand	Broadcom
Model	NetXtreme/NetLink BCM5718 Series
Category	Controller
Language	English