How to configure Ethernet switch

Applicable for

Unknown MPU

"STM32MP25" is not in the list (STM32MP13x, STM32MP15x, STM32MP25x) of allowed values for the "Has applicability specified for" property.

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1. Purpose

This article describes how to configure the Ethernet switch.

2. For GMAC standalone configuration

100% same sequence than MP1

3. For Switch configuration

ETH1  Stm32-deip glue  edge-lkml File describing the probe scheme are located on board in:

 /etc/modprobe.d/edgx_sw_modprobe.cnf
 /etc/modprobe.d/acm_modprobe.cnf

During edge-lkml probe, the interface on which the switch internal port is connected is given as parameter:

 Ex: edgx_pfm_lkm netif="end1:0"
 In: /etc/modprobe.d/edgx_sw_core.conf

3.1. Ethernet switch interface

Ethernet Switch interfaces

Use ifconfig to list interfaces:

end0: standalone GMAC interface

end1: SW interface for ETH1 GMAC Connected to switch internal port Will not have IP address!

Sw0p1: Internal port interface Will not have IP address!

Sw0p2: External port interface connected to ETH3 port Will not have IP address!

Sw0p3: External port interface connected to ETH1 port Will not have IP address!

Sw0ep: « endpoint » interface Used to communicate to/from the MP25 through external ports

Those interfaces are set during boot thanks to this script: /usr/sbin/ttt-ip-init-systemd.sh

3.1.1. more details about /usr/sbin/ttt-ip-init-systemd.sh

Bridge setup (as described above)

Services startup:

• Start deptp:

   proprietary PTP stack provided by TTTech used for gPTP synchronization

• Start LLDP (Link Layer Discovery Protocol):

   Use to exchange informations (name, capabilities) with other connected devices

• Start SNMPD:

   Use to collect data from the switch

• Configure MSTP (through « mstpctl »)

   Used for spanning tree management (to avoid loop in a network)

• PHY configuration:

   Affect PHY to the well switch port:
     echo -n stmmac-1:05 > /sys/devices/platform/soc/$IP_REF_NAME/net/sw0p3/phy/mdiobus
     echo -n stmmac-1:04 > /sys/devices/platform/soc/$IP_REF_NAME/net/sw0p2/phy/mdiobus
     (ls –al /sys/bus/mdio_bus/devices/ to know which mdio bus refers to GMAC ETH1)

Warning

This has to be updated for customer PHY

• Add phy delays:

   Used by the switch to compute his propagation delay (used for gPTP)
    echo 84 > /sys/class/net/sw0p2/phy/delay1000tx_min     
    echo 92 > /sys/class/net/sw0p2/phy/delay1000tx_max                     
    echo 84 > /sys/class/net/sw0p3/phy/delay1000tx_min                          
    echo 92 > /sys/class/net/sw0p3/phy/delay1000tx_max                                    
    echo 0 > /sys/class/net/sw0p2/phy/delay1000rx_min                                     
    echo 250 > /sys/class/net/sw0p2/phy/delay1000rx_max                                   
    echo 0 > /sys/class/net/sw0p3/phy/delay1000rx_min                                     
    echo 250 > /sys/class/net/sw0p3/phy/delay1000rx_max

Warning

Value to be found in PHY datasheet

Warning

100 Mbps values are currently missing

  ifconfig eth0 uuu.xxx.yyy.zzz

To check if eth0 and the gateway are well configured, one can type:

 ifconfig
 route

In the console, a log similar to the one below should be displayed:

  ifconfig
 eth0      Link encap:Ethernet  HWaddr 00:80:E1:01:39:61  
           inet addr:10.48.1.172  Bcast:10.48.3.255  Mask:255.255.252.0
           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
           RX packets:18 errors:0 dropped:0 overruns:0 frame:0
           TX packets:2 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 txqueuelen:1000 
           RX bytes:3038 (2.9 KiB)  TX bytes:684 (684.0 B)
           Interrupt:103 
 STM32MP1 # route
 Kernel IP routing table
 Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
 default         lme-gw-vl802.lm 0.0.0.0         UG    10     0        0 eth0
 10.48.0.0       *               255.255.252.0   U     0      0        0 eth0

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