Verilog Ethernet Switch (layer 2)

Features:

• Parameterized Number of Ports
• Parameterized MAC-Table (based on dual-port CAM, complexity O(1))
• Flooding and Broadcasting
• CRC Checking
• Static or Dynamic MAC-Table

Compatible Ethernet Frame

Common Ethernet Switch Structure

Dual-Port CAM

Structure

Dual-port scheme allows to execute simultaneous request to MAC-Table for SOURCE and DESTINATION ports respectively.

Mode

Static

In this mode MAC-Table do not update itself on the fly. For MAC-Table configuration port s_axis_config_* must be used.

Dynamic

In this mode MAC-Table works in 'normal' mode. It dynamically update itself.

AXIS Interconnect

Arbiter scheduling: Round-Robin

Parameters

• PORT_NUM - Number of ports (must be power of '2')
• ADDR_WIDTH - Address width of MAC-Table
• ETHERNET_MTU - Ethernet Maximum Transmismission Unit
• FLOODING_ENABLE - Enables (1) or disables (0) Flooding technique
• CRC_CHECK - Enables (1) or disables (0) CRC Checking (last 4 octets, if presented)
• RAM_STYLE_DATA - Type of RAM ("block" or "distributed")
• MODE - Mode of MAC-Table ("dynamic" or "static")

Ports

• aclk - Clock
• aresetn - Synchronous reset (active-LOW)
• s_axis_tdata - Input data
• s_axis_tvalid - Input 'Valid' signal
• s_axis_tready - Output 'Ready' signal
• s_axis_tlast - Input 'Last' transfer signal (end of frame)
• m_axis_tdata - Output data
• m_axis_tvalid - Output 'Valid' signal
• m_axis_tready - Input 'Ready' signal
• m_axis_tlast - Output 'Last' transfer signal (end of frame)
• s_axis_config_tdata - Input MAC-Table Configuration Data (if MODE == "static")
• s_axis_config_tuser - Input MAC-Table Configuration 'User' signal (if MODE == "static")
• s_axis_config_tvalid - Input MAC-Table Configuration 'Valid' signal (if MODE == "static")

Data Format

• s_axis_tdata[8*1-1-:8] - Channel #0 Data
• s_axis_tdata[8*2-1-:8] - Channel #1 Data
• ...
• s_axis_tdata[8*PORT_NUM-1-:8] - Channel #(PORT_NUM-1) Data

Configuration Data Format

• s_axis_tdata[ADDR_WIDTH-1-:ADDR_WIDTH] - Address of CAM cell
• s_axis_tdata[$clog2(PORT_NUM)+ADDR_WIDTH-1-:$clog2(PORT_NUM)] - Port Number (from 0 to PORT_NUM-1)
• s_axis_tdata[48+$clog2(PORT_NUM)+ADDR_WIDTH-1-:48] - Destination MAC-address