3.2.3.8.3.4. IET¶

Warning: IET with Fixed-Link Interface
IET in MAC mode
- AM625-SK fragments frames and J7VCL assembles them
- J7VCL fragments frames and AM625-SK assembles them
IET in Switch mode

3.2.3.8.3.4.1. Warning: IET with Fixed-Link Interface ¶

If one of the interfaces which takes part in IET is in fixed-link mode, then do NOT enable MAC verify for IET on either of the devices connected to each other directly by the LAN cable. This is because, in the case of fixed-link, the link state cannot be detected by interfaces on either side of the link. The process of IET MAC Verification depends on the link state being toggled, with the verification starting immediately after the link comes up and lasting for 1 second. Thus, unless this process starts roughly simultaneously on both interfaces connected over the link (Which would happen in the non fixed-link case), IET MAC Verification would fail with a Timeout message, thereby causing frame fragmentation to fail.

Thus, if either of the interfaces that are directly connected by a LAN cable, is in fixed-link mode, then do NOT enable MAC verify on BOTH the interfaces. Simply enable IET Frame Preemption on both devices and IET will work. The rest of the steps are the same as documented in the upcoming sectionss.

IET MAC Verification in ethtool corresponds to:

iet-mac-verify

IET Frame Preemption in ethtool corresponds to:

iet-frame-preemption

3.2.3.8.3.4.2. IET in MAC mode ¶

3.2.3.8.3.4.2.1. AM625-SK fragments frames and J7VCL assembles them ¶

Connect eth0 of AM625-SK to eth1 of J7VCL.

Steps:

Create and run the following script on J7VCL:

#!/bin/sh

ifconfig eth1 down
ifconfig eth2 down
ifconfig eth3 down
ifconfig eth4 down
ethtool -L eth1 tx 2
ethtool --set-priv-flags eth1 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth1 iet-frame-preemption on
ethtool --set-priv-flags eth1 iet-mac-verify on
ifconfig eth1 up
sleep 5

iperf3 -s -i30 -p5002&
iperf3 -s -i30 -p5003&

Create and run the following script on AM625-SK:

#!/bin/sh

ifconfig eth0 down
ifconfig eth1 down
ethtool -L eth0 tx 2
ethtool --set-priv-flags eth0 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth0 iet-frame-preemption on
ethtool --set-priv-flags eth0 iet-mac-verify on
ifconfig eth0 up
sleep 5

tc qdisc replace dev eth0 handle 100: parent root mqprio \
    num_tc 2 \
    map 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 \
    queues 1@0 1@1 \
    hw 0

tc -g class show dev eth0
tc qdisc add dev eth0 clsact
tc filter add dev eth0 egress protocol ip prio 1 u32 match ip dport 5002 0xffff action skbedit priority 2
tc filter add dev eth0 egress protocol ip prio 1 u32 match ip dport 5003 0xffff action skbedit priority 3
ip addr add 192.168.100.20/24 dev eth0
sleep 2

On J7VCL, run the following command:

ifconfig eth1 192.168.100.30

Now, run the following commands on AM625-SK:

iperf3 -c 192.168.100.30 -u -b200M -l1472 -u -t30 -i30 -p5002&
iperf3 -c 192.168.100.30 -u -b50M -l1472 -u -t30 -i30 -p5003&

Results:

On AM625-SK (Sender):

root@am62xx-evm:~/IET# ethtool -S eth0 | grep 'tx_pri1'
     p0_tx_pri1: 0
     p0_tx_pri1_bcnt: 0
     p0_tx_pri1_drop: 0
     p0_tx_pri1_drop_bcnt: 0
     tx_pri1: 127400
     tx_pri1_bcnt: 193357542
     tx_pri1_drop: 0
     tx_pri1_drop_bcnt: 0
root@am62xx-evm:~/IET# ethtool -S eth0 | grep 'tx_pri0'
     p0_tx_pri0: 67
     p0_tx_pri0_bcnt: 10496
     p0_tx_pri0_drop: 0
     p0_tx_pri0_drop_bcnt: 0
     tx_pri0: 509608
     tx_pri0_bcnt: 773438547
     tx_pri0_drop: 0
     tx_pri0_drop_bcnt: 0
root@am62xx-evm:~/IET# ethtool -S eth0 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 0
     iet_rx_smd_err: 63
     iet_rx_frag: 0
     iet_tx_hold: 0
     iet_tx_frag: 120056

On J7VCL (Receiver):

root@j7200-evm:~/IET# ethtool -S eth1 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 32334
     iet_rx_smd_err: 1
     iet_rx_frag: 120056
     iet_tx_hold: 0
     iet_tx_frag: 0

Explanation:

On AM625-SK, the higher priority traffic preempts the lower priority
traffic, thereby resulting in the fragmentation of frames of lower
priority. This can be seen in the iet_tx_frag statistic on AM625-SK.

Similarly, on J7VCL, the received fragmented frames can be observed
in the iet_rx_frag statistic, while the assembled frames can be seen
in the iet_rx_assembly_ok statistic.

3.2.3.8.3.4.2.2. J7VCL fragments frames and AM625-SK assembles them ¶

Connect eth1 of J7VCL to eth0 of AM625-SK.

Steps:

Create and run the following script on AM625-SK:

#!/bin/sh

ifconfig eth0 down
ifconfig eth1 down
ethtool -L eth0 tx 2
ethtool --set-priv-flags eth0 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth0 iet-frame-preemption on
ethtool --set-priv-flags eth0 iet-mac-verify on
ifconfig eth0 up
sleep 5

iperf3 -s -i30 -p5002&
iperf3 -s -i30 -p5003&

Create and run the following script on J7VCL:

#!/bin/sh

ifconfig eth1 down
ifconfig eth2 down
ifconfig eth3 down
ifconfig eth4 down
ethtool -L eth1 tx 2
ethtool --set-priv-flags eth1 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth1 iet-frame-preemption on
ethtool --set-priv-flags eth1 iet-mac-verify on
ifconfig eth1 up
sleep 5

tc qdisc replace dev eth1 handle 100: parent root mqprio \
    num_tc 2 \
    map 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 \
    queues 1@0 1@1 \
    hw 0

tc -g class show dev eth1
tc qdisc add dev eth1 clsact
tc filter add dev eth1 egress protocol ip prio 1 u32 match ip dport 5002 0xffff action skbedit priority 2
tc filter add dev eth1 egress protocol ip prio 1 u32 match ip dport 5003 0xffff action skbedit priority 3
ip addr add 192.168.100.20/24 dev eth1
sleep 2

Run the following command on AM625-SK:

ifconfig eth0 192.168.100.30

Next, run the following commands on J7VCL:

iperf3 -c 192.168.100.30 -u -b200M -l1472 -u -t30 -i30 -p5002&
iperf3 -c 192.168.100.30 -u -b50M -l1472 -u -t30 -i30 -p5003&

Results:

On J7VCL (Sender):

root@j7200-evm:~/IET# ethtool -S eth1 | grep 'tx_pri1'
     p0_tx_pri1: 0
     p0_tx_pri1_bcnt: 0
     p0_tx_pri1_drop: 0
     p0_tx_pri1_drop_bcnt: 0
     tx_pri1: 254787
     tx_pri1_bcnt: 386711048
     tx_pri1_drop: 0
     tx_pri1_drop_bcnt: 0
root@j7200-evm:~/IET# ethtool -S eth1 | grep 'tx_pri0'
     p0_tx_pri0: 110
     p0_tx_pri0_bcnt: 16002
     p0_tx_pri0_drop: 0
     p0_tx_pri0_drop_bcnt: 0
     tx_pri0: 1019126
     tx_pri0_bcnt: 1546856078
     tx_pri0_drop: 0
     tx_pri0_drop_bcnt: 0
root@j7200-evm:~/IET# ethtool -S eth1 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 0
     iet_rx_smd_err: 36
     iet_rx_frag: 0
     iet_tx_hold: 0
     iet_tx_frag: 42

On AM625-SK (Receiver):

root@am62xx-evm:~/IET# ethtool -S eth0 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 29
     iet_rx_smd_err: 1
     iet_rx_frag: 42
     iet_tx_hold: 0
     iet_tx_frag: 0

Explanation:

On J7VCL, the higher priority traffic preempts the lower priority
traffic, thereby resulting in the fragmentation of frames of lower
priority. This can be seen in the iet_tx_frag statistic on J7VCL.

Similarly, on AM625-SK, the received fragmented frames can be observed
in the iet_rx_frag statistic, while the assembled frames can be seen
in the iet_rx_assembly_ok statistic.

3.2.3.8.3.4.3. IET in Switch mode ¶

3 Devices are connected: Sender, Switch and Receiver.

3 Cases:

Frame is preempted on Sender and Assembled on Switch Ingress Port.
Frame is preempted on Switch Egress Port and Assembled on Receiver.
Frame is preempted on Sender and Assembled on Switch Ingress Port, and also, frame is preempted on Switch Egress Port and Assembled on Receiver.

Devices Used:

AM625-SK (As Switch/Sender)
J7VCL (As Switch/Sender)
AM64-SK (As Receiver)

3.2.3.8.3.4.3.1. CASE-1: Frame is preempted on Sender and Assembled on Switch Ingress Port ¶

3.2.3.8.3.4.3.1.1. Preemption on AM625-SK (Sender) and Assembly on J7VCL (Switch) Ingress Port and sent to AM64-SK (Receiver)¶

Connect eth0 of AM625-SK to eth1 of J7VCL and eth0 of AM64-SK to eth2 of J7VCL.

Steps:

On J7VCL, create and run the following script:

#!/bin/sh

ifconfig eth1 down
ifconfig eth2 down
ifconfig eth3 down
ifconfig eth4 down
ethtool -L eth1 tx 2
ethtool --set-priv-flags eth1 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth1 iet-frame-preemption on
ethtool --set-priv-flags eth1 iet-mac-verify on
ifconfig eth1 up
ifconfig eth2 up
sleep 5

devlink dev param set platform/c000000.ethernet name switch_mode value true cmode runtime
ip link add name br0 type bridge
ip link set dev br0 type bridge ageing_time 1000
ip link set dev eth1 up
ip link set dev eth2 up
ip link set dev eth1 master br0
ip link set dev eth2 master br0
ip link set dev br0 up
ip link set dev br0 type bridge vlan_filtering 1
bridge vlan add dev br0 vid 1 pvid untagged self

On AM625-SK, create and run the following script:

#!/bin/sh

ifconfig eth0 down
ifconfig eth1 down
ethtool -L eth0 tx 2
ethtool --set-priv-flags eth0 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth0 iet-frame-preemption on
ethtool --set-priv-flags eth0 iet-mac-verify on
ifconfig eth0 up
sleep 5

tc qdisc replace dev eth0 handle 100: parent root mqprio \
    num_tc 2 \
    map 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 \
    queues 1@0 1@1 \
    hw 0

tc -g class show dev eth0
tc qdisc add dev eth0 clsact
tc filter add dev eth0 egress protocol ip prio 1 u32 match ip dport 5002 0xffff action skbedit priority 2
tc filter add dev eth0 egress protocol ip prio 1 u32 match ip dport 5003 0xffff action skbedit priority 3
ifconfig eth0 192.168.100.20 netmask 255.255.255.0
sleep 2

On AM64-SK, run the following commands:

ifconfig eth0 192.168.100.30
iperf3 -s -i30 -p5002& \
iperf3 -s -i30 -p5003&

Then, on AM625-SK, run the following commands:

iperf3 -c 192.168.100.30 -u -b200M -l1472 -u -t30 -i30 -p5002& \
iperf3 -c 192.168.100.30 -u -b50M -l1472 -u -t30 -i30 -p5003&

Results:

On AM625-SK (Sender):

root@am62xx-evm:~/IET# ethtool -S eth0 | grep 'tx_pri1'
     p0_tx_pri1: 0
     p0_tx_pri1_bcnt: 0
     p0_tx_pri1_drop: 0
     p0_tx_pri1_drop_bcnt: 0
     tx_pri1: 127395
     tx_pri1_bcnt: 193357336
     tx_pri1_drop: 0
     tx_pri1_drop_bcnt: 0
root@am62xx-evm:~/IET# ethtool -S eth0 | grep 'tx_pri0'
     p0_tx_pri0: 165
     p0_tx_pri0_bcnt: 34444
     p0_tx_pri0_drop: 0
     p0_tx_pri0_drop_bcnt: 0
     tx_pri0: 509721
     tx_pri0_bcnt: 773459795
     tx_pri0_drop: 0
     tx_pri0_drop_bcnt: 0
root@am62xx-evm:~/IET# ethtool -S eth0 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 0
     iet_rx_smd_err: 128
     iet_rx_frag: 0
     iet_tx_hold: 0
     iet_tx_frag: 114

On J7VCL (Switch):

root@j7200-evm:~/IET# ethtool -S eth1 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 108
     iet_rx_smd_err: 1
     iet_rx_frag: 114
     iet_tx_hold: 0
     iet_tx_frag: 0

3.2.3.8.3.4.3.1.2. Preemption on J7VCL (Sender) and Assembly on AM625-SK (Switch) Ingress Port and sent to AM64-SK (Receiver)¶

Connect eth1 of J7VCL to eth0 of AM625-SK and eth0 of AM64-SK to eth1 of AM625-SK.

Steps:

On AM625-SK, create and run the following script:

#!/bin/sh

ifconfig eth0 down
ifconfig eth1 down
ethtool -L eth0 tx 2
ethtool --set-priv-flags eth0 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth0 iet-frame-preemption on
ethtool --set-priv-flags eth0 iet-mac-verify on
ifconfig eth0 up
ifconfig eth1 up
sleep 5

devlink dev param set platform/8000000.ethernet name switch_mode value true cmode runtime
ip link add name br0 type bridge
ip link set dev br0 type bridge ageing_time 1000
ip link set dev eth0 up
ip link set dev eth1 up
ip link set dev eth0 master br0
ip link set dev eth1 master br0
ip link set dev br0 up
ip link set dev br0 type bridge vlan_filtering 1
bridge vlan add dev br0 vid 1 pvid untagged self

On J7VCL, create and run the following script:

#!/bin/sh

ifconfig eth1 down
ifconfig eth2 down
ifconfig eth3 down
ifconfig eth4 down
ethtool -L eth1 tx 2
ethtool --set-priv-flags eth1 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth1 iet-frame-preemption on
ethtool --set-priv-flags eth1 iet-mac-verify on
ifconfig eth1 up
sleep 5

tc qdisc replace dev eth1 handle 100: parent root mqprio \
    num_tc 2 \
    map 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 \
    queues 1@0 1@1 \
    hw 0

tc -g class show dev eth1
tc qdisc add dev eth1 clsact
tc filter add dev eth1 egress protocol ip prio 1 u32 match ip dport 5002 0xffff action skbedit priority 2
tc filter add dev eth1 egress protocol ip prio 1 u32 match ip dport 5003 0xffff action skbedit priority 3
ifconfig eth1 192.168.100.20 netmask 255.255.255.0
sleep 2

On AM64-SK, run the following commands:

ifconfig eth0 192.168.100.30
iperf3 -s -i30 -p5002& \
iperf3 -s -i30 -p5003&

Then, on J7VCL, run the following commands:

iperf3 -c 192.168.100.30 -u -b200M -l1472 -u -t30 -i30 -p5002& \
iperf3 -c 192.168.100.30 -u -b50M -l1472 -u -t30 -i30 -p5003&

Results:

On J7VCL (Sender):

root@j7200-evm:~/IET# ethtool -S eth1 | grep 'tx_pri1'
     p0_tx_pri1: 0
     p0_tx_pri1_bcnt: 0
     p0_tx_pri1_drop: 0
     p0_tx_pri1_drop_bcnt: 0
     tx_pri1: 127396
     tx_pri1_bcnt: 193356005
     tx_pri1_drop: 0
     tx_pri1_drop_bcnt: 0
root@j7200-evm:~/IET# ethtool -S eth1 | grep 'tx_pri0'
     p0_tx_pri0: 76
     p0_tx_pri0_bcnt: 14563
     p0_tx_pri0_drop: 0
     p0_tx_pri0_drop_bcnt: 0
     tx_pri0: 509604
     tx_pri0_bcnt: 773435752
     tx_pri0_drop: 0
     tx_pri0_drop_bcnt: 0
root@j7200-evm:~/IET# ethtool -S eth1 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 0
     iet_rx_smd_err: 10
     iet_rx_frag: 0
     iet_tx_hold: 0
     iet_tx_frag: 77331

On AM625-SK (Switch):

root@am62xx-evm:~/IET# ethtool -S eth0 | grep iet
     iet_rx_assembly_err: 11
     iet_rx_assembly_ok: 20790
     iet_rx_smd_err: 1092
     iet_rx_frag: 77300
     iet_tx_hold: 0
     iet_tx_frag: 0

3.2.3.8.3.4.3.2. CASE-2: Frame is preempted on Switch Egress Port and Assembled on Receiver ¶

Note

For the following tests, all interfaces which are a part of the test need to be a part of the same VLAN, since the switch needs to receive priority of the frames in order to perform preemption.

In addition to the Sender, the Switch’s Host Port also transmits traffic of lower priority to the receiver. This is done to ensure a higher chance of frame preemption and therefore frame fragmentation on the Switch’ Egress Port.

3.2.3.8.3.4.3.2.1. Highest priority frame sent by AM625-SK with preemption on J7VCL’s (Switch) Egress Port and Assembly on AM64-SK¶

Connect eth0 of AM625-SK to eth1 of J7VCL and eth0 of AM64-SK to eth2 of J7VCL.

Steps:

Create and run the following script on J7VCL:

#!/bin/sh

ifconfig eth1 down
ifconfig eth2 down
ifconfig eth3 down
ifconfig eth4 down
ethtool -L eth2 tx 2
ethtool --set-priv-flags eth2 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth2 iet-frame-preemption on
ethtool --set-priv-flags eth2 iet-mac-verify on
ifconfig eth1 up
ifconfig eth2 up
sleep 5

tc qdisc replace dev eth2 handle 100: parent root mqprio \
    num_tc 2 \
    map 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 \
    queues 1@0 1@1 \
    hw 0

tc -g class show dev eth2

devlink dev param set platform/c000000.ethernet name switch_mode value true cmode runtime
ip link add name br0 type bridge
ip link set dev br0 type bridge ageing_time 1000
ip link set dev eth1 up
ip link set dev eth2 up
ip link set dev eth1 master br0
ip link set dev eth2 master br0
ip link set dev br0 up
sleep 2

ip link set dev br0 type bridge vlan_filtering 1
bridge vlan add dev br0 vid 100 pvid tagged self
bridge vlan add dev eth1 vid 100 master
bridge vlan add dev eth2 vid 100 master
sleep 2

ip link add link br0 name br0.100 type vlan id 100
ip link set br0.100 type vlan egress 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
sleep 2

tc qdisc add dev br0.100 clsact
tc filter add dev br0.100 egress protocol ip prio 1 u32 match ip dport 5002 0xffff action skbedit priority 2
sleep 2

Create and run the following script on AM64-SK:

#!/bin/sh

ifconfig eth0 down
ifconfig eth1 down
ethtool -L eth0 tx 2
ethtool --set-priv-flags eth0 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth0 iet-frame-preemption on
ethtool --set-priv-flags eth0 iet-mac-verify on
ifconfig eth0 up
sleep 5

ip link add link eth0 name eth0.100 type vlan id 100
sleep 5
ifconfig eth0.100 192.168.100.30
iperf3 -s -i30 -p5001&
iperf3 -s -i30 -p5002&
iperf3 -s -i30 -p5003&

Create and run the following script on AM625-SK:

#!/bin/sh

ifconfig eth0 down
ifconfig eth1 down
ethtool -L eth0 tx 2
ethtool --set-priv-flags eth0 p0-rx-ptype-rrobin off
ifconfig eth0 up
sleep 5
ip link add link eth0 name eth0.100 type vlan id 100
ip link set eth0.100 type vlan egress 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
sleep 5

tc qdisc add dev eth0.100 clsact
tc filter add dev eth0.100 egress protocol ip prio 1 u32 match ip dport 5003 0xffff action skbedit priority 3
ifconfig eth0.100 192.168.100.20 netmask 255.255.255.0
sleep 2

Run the following commands on J7VCL:

ifconfig br0.100 192.168.100.10
sleep 10
iperf3 -c 192.168.100.30 -u -b100M -l1472 t30 -i30 -p5001&
iperf3 -c 192.168.100.30 -u -b100M -l1472 t30 -i30 -p5002&

Now, run the following command on AM625-SK:

iperf3 -c 192.168.100.30 -u -b50M -l1472 -t30 -i30 -p5003&

Results:

On J7VCL (Switch):

root@j7200-evm:~/IET# ethtool -S eth2 | grep 'tx_pri0'
     p0_tx_pri0: 173
     p0_tx_pri0_bcnt: 31039
     p0_tx_pri0_drop: 0
     p0_tx_pri0_drop_bcnt: 0
     tx_pri0: 85135
     tx_pri0_bcnt: 129274224
     tx_pri0_drop: 0
     tx_pri0_drop_bcnt: 0
root@j7200-evm:~/IET# ethtool -S eth2 | grep 'tx_pri2'
     p0_tx_pri2: 0
     p0_tx_pri2_bcnt: 0
     p0_tx_pri2_drop: 0
     p0_tx_pri2_drop_bcnt: 0
     tx_pri2: 84932
     tx_pri2_bcnt: 129237975
     tx_pri2_drop: 0
     tx_pri2_drop_bcnt: 0
root@j7200-evm:~/IET# ethtool -S eth2 | grep 'tx_pri3'
     p0_tx_pri3: 0
     p0_tx_pri3_bcnt: 0
     p0_tx_pri3_drop: 0
     p0_tx_pri3_drop_bcnt: 0
     tx_pri3: 3775
     tx_pri3_bcnt: 5717026
     tx_pri3_drop: 0
     tx_pri3_drop_bcnt: 0
root@j7200-evm:~/IET# ethtool -S eth2 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 0
     iet_rx_smd_err: 2
     iet_rx_frag: 0
     iet_tx_hold: 0
     iet_tx_frag: 107

On AM64-SK (Receiver):

root@am64xx-evm:~# ethtool -S eth0 | grep iet
     iet_rx_assembly_err: 1
     iet_rx_assembly_ok: 94
     iet_rx_smd_err: 72
     iet_rx_frag: 106
     iet_tx_hold: 0
     iet_tx_frag: 0

3.2.3.8.3.4.3.2.2. Highest priority frame sent by J7VCL with preemption on AM625-SK’s (Switch) Egress Port and Assembly on AM64-SK¶

Connect eth1 of J7VCL to eth0 of AM625-SK and eth0 of AM64-SK to eth1 of AM625-SK.

Steps:

On AM625-SK, create and run the following script:

#!/bin/sh

ifconfig eth0 down
ifconfig eth1 down
ethtool -L eth1 tx 2
ethtool --set-priv-flags eth1 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth1 iet-frame-preemption on
ethtool --set-priv-flags eth1 iet-mac-verify on
ifconfig eth0 up
ifconfig eth1 up
sleep 5

tc qdisc replace dev eth1 handle 100: parent root mqprio \
    num_tc 2 \
    map 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 \
    queues 1@0 1@1 \
    hw 0

tc -g class show dev eth1

devlink dev param set platform/8000000.ethernet name switch_mode value true cmode runtime
ip link add name br0 type bridge
ip link set dev br0 type bridge ageing_time 1000
ip link set dev eth0 up
ip link set dev eth1 up
ip link set dev eth0 master br0
ip link set dev eth1 master br0
ip link set dev br0 up
sleep 2

ip link set dev br0 type bridge vlan_filtering 1
bridge vlan add dev br0 vid 100 pvid tagged self
bridge vlan add dev eth0 vid 100 master
bridge vlan add dev eth1 vid 100 master
sleep 2

ip link add link br0 name br0.100 type vlan id 100
ip link set br0.100 type vlan egress 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
sleep 2

tc qdisc add dev br0.100 clsact
tc filter add dev br0.100 egress protocol ip prio 1 u32 match ip dport 5002 0xffff action skbedit priority 2
sleep 2

On AM64-SK, create and run the following script:

#!/bin/sh

ifconfig eth0 down
ifconfig eth1 down
ethtool -L eth0 tx 2
ethtool --set-priv-flags eth0 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth0 iet-frame-preemption on
ethtool --set-priv-flags eth0 iet-mac-verify on
ifconfig eth0 up
sleep 5

ip link add link eth0 name eth0.100 type vlan id 100
sleep 5
ifconfig eth0.100 192.168.100.30
iperf3 -s -i30 -p5002&
iperf3 -s -i30 -p5003&

On J7VCL, create and run the following script:

#!/bin/sh

ifconfig eth1 down
ifconfig eth2 down
ifconfig eth3 down
ifconfig eth4 down
ethtool -L eth1 tx 2
ethtool --set-priv-flags eth1 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth1 iet-frame-preemption on
ethtool --set-priv-flags eth1 iet-mac-verify on
ifconfig eth1 up
sleep 5

tc qdisc replace dev eth1 handle 100: parent root mqprio \
    num_tc 2 \
    map 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 \
    queues 1@0 1@1 \
    hw 0

tc -g class show dev eth1

ip link add link eth1 name eth1.100 type vlan id 100
ip link set eth1.100 type vlan egress 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
sleep 5

tc qdisc add dev eth1.100 clsact
tc filter add dev eth1.100 egress protocol ip prio 1 u32 match ip dport 5003 0xffff action skbedit priority 3
ifconfig eth1.100 192.168.100.20 netmask 255.255.255.0
sleep 2

Run the following commands on AM625-SK:

ifconfig br0.100 192.168.100.10
sleep 10
iperf3 -c 192.168.100.30 -u -b100M -l1472 t30 -i30 -p5001& \
iperf3 -c 192.168.100.30 -u -b100M -l1472 t30 -i30 -p5002&

Now, on J7VCL, run the following command:

iperf3 -c 192.168.100.30 -u -b50M -l1472 -t30 -i30 -p5003&

Results:

On AM625-SK (Switch):

root@am62xx-evm:~/IET# ethtool -S eth1 | grep 'tx_pri0
     p0_tx_pri0: 228
     p0_tx_pri0_bcnt: 44010
     p0_tx_pri0_drop: 0
     p0_tx_pri0_drop_bcnt: 0
     tx_pri0: 792
     tx_pri0_bcnt: 938162
     tx_pri0_drop: 0
     tx_pri0_drop_bcnt: 0
root@am62xx-evm:~/IET# ethtool -S eth1 | grep 'tx_pri2'
     p0_tx_pri2: 0
     p0_tx_pri2_bcnt: 0
     p0_tx_pri2_drop: 0
     p0_tx_pri2_drop_bcnt: 0
     tx_pri2: 706
     tx_pri2_bcnt: 1047447
     tx_pri2_drop: 0
     tx_pri2_drop_bcnt: 0
root@am62xx-evm:~/IET# ethtool -S eth1 | grep 'tx_pri3'
     p0_tx_pri3: 0
     p0_tx_pri3_bcnt: 0
     p0_tx_pri3_drop: 0
     p0_tx_pri3_drop_bcnt: 0
     tx_pri3: 127393
     tx_pri3_bcnt: 193865046
     tx_pri3_drop: 0
     tx_pri3_drop_bcnt: 0
root@am62xx-evm:~/IET# ethtool -S eth1 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 0
     iet_rx_smd_err: 0
     iet_rx_frag: 0
     iet_tx_hold: 0
     iet_tx_frag: 54

On AM64-SK (Receiver):

root@am64xx-evm:~# ethtool -S eth0 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 23
     iet_rx_smd_err: 120
     iet_rx_frag: 54
     iet_tx_hold: 0
     iet_tx_frag: 0

3.2.3.8.3.4.3.3. CASE-3: Frame is preempted on both Sender and Switch Egress Port ¶

Note

For the following tests, all interfaces which are a part of the test need to be a part of the same VLAN, since the switch needs to receive priority of the frames in order to perform preemption.

In addition to the Sender, the Switch’s Host Port also transmits traffic of lower priority to the receiver. This is done to ensure a higher chance of frame preemption and therefore frame fragmentation on the Switch’ Egress Port.

CASE-3 is the same as CASE-1 and CASE-2 combined.

3.2.3.8.3.4.3.3.1. Frame sent by AM625-SK with preemption on AM625-SK Egress Port and Assembled on J7VCL’s (Switch) Ingress Port followed by preemption on J7VCL’s (Switch) Egress Port and Assembled on AM64-SK¶

Connect eth0 of AM625-SK to eth1 of J7VCL and eth0 of AM64-SK to eth2 of J7VCL.

Steps:

Create and run the following script on J7VCL:

#!/bin/sh

ifconfig eth1 down
ifconfig eth2 down
ifconfig eth3 down
ifconfig eth4 down
ethtool -L eth1 tx 2
ethtool --set-priv-flags eth1 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth1 iet-frame-preemption on
ethtool --set-priv-flags eth1 iet-mac-verify on
ethtool -L eth2 tx 2
ethtool --set-priv-flags eth2 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth2 iet-frame-preemption on
ethtool --set-priv-flags eth2 iet-mac-verify on
ifconfig eth1 up
ifconfig eth2 up
sleep 5

tc qdisc replace dev eth2 handle 100: parent root mqprio \
    num_tc 2 \
    map 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 \
    queues 1@0 1@1 \
    hw 0

tc -g class show dev eth2

devlink dev param set platform/c000000.ethernet name switch_mode value true cmode runtime
ip link add name br0 type bridge
ip link set dev br0 type bridge ageing_time 1000
ip link set dev eth1 up
ip link set dev eth2 up
ip link set dev eth1 master br0
ip link set dev eth2 master br0
ip link set dev br0 up
sleep 2

ip link set dev br0 type bridge vlan_filtering 1
bridge vlan add dev br0 vid 100 pvid tagged self
bridge vlan add dev eth1 vid 100 master
bridge vlan add dev eth2 vid 100 master
sleep 2

ip link add link br0 name br0.100 type vlan id 100
ip link set br0.100 type vlan egress 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
sleep 2

tc qdisc add dev br0.100 clsact
tc filter add dev br0.100 egress protocol ip prio 1 u32 match ip dport 5002 0xffff action skbedit priority 2
sleep 2

Create and run the following script on AM64-SK:

#!/bin/sh

ifconfig eth0 down
ifconfig eth1 down
ethtool -L eth0 tx 2
ethtool --set-priv-flags eth0 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth0 iet-frame-preemption on
ethtool --set-priv-flags eth0 iet-mac-verify on
ifconfig eth0 up
sleep 5

ip link add link eth0 name eth0.100 type vlan id 100
sleep 5
ifconfig eth0.100 192.168.100.30
iperf3 -s -i30 -p5001&
iperf3 -s -i30 -p5002&
iperf3 -s -i30 -p5003&
iperf3 -s -i30 -p5004&
iperf3 -s -i30 -p5005&

Create and run the following script on AM625-SK:

#!/bin/sh

ifconfig eth0 down
ifconfig eth1 down
ethtool -L eth0 tx 2
ethtool --set-priv-flags eth0 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth0 iet-frame-preemption on
ethtool --set-priv-flags eth0 iet-mac-verify on
ifconfig eth0 up
sleep 5
ip link add link eth0 name eth0.100 type vlan id 100
ip link set eth0.100 type vlan egress 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
sleep 5

tc qdisc add dev eth0.100 clsact
tc filter add dev eth0.100 egress protocol ip prio 1 u32 match ip dport 5003 0xffff action skbedit priority 2
tc filter add dev eth0.100 egress protocol ip prio 1 u32 match ip dport 5004 0xffff action skbedit priority 3
ifconfig eth0.100 192.168.100.20 netmask 255.255.255.0
sleep 2

Run the following commands on J7VCL:

ifconfig br0.100 192.168.100.10
sleep 10
iperf3 -c 192.168.100.30 -u -b100M -l1472 t30 -i30 -p5001& \
iperf3 -c 192.168.100.30 -u -b100M -l1472 t30 -i30 -p5002&

Now, run the following commands on AM625-SK:

iperf3 -c 192.168.100.30 -u -b100M -l1472 -t30 -i30 -p5003& \
iperf3 -c 192.168.100.30 -u -b50M -l1472 -t30 -i30 -p5004& \
iperf3 -c 192.168.100.30 -u -b100M -l1472 -t30 -i30 -p5005&

Results:

On AM625-SK (Sender):

root@am62xx-evm:~/IET# ethtool -S eth0 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 0
     iet_rx_smd_err: 63
     iet_rx_frag: 0
     iet_tx_hold: 0
     iet_tx_frag: 4

On J7VCL (Switch):

root@j7200-evm:~/IET# ethtool -S eth1 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 4
     iet_rx_smd_err: 1
     iet_rx_frag: 4
     iet_tx_hold: 0
     iet_tx_frag: 0
root@j7200-evm:~/IET# ethtool -S eth2 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 0
     iet_rx_smd_err: 1
     iet_rx_frag: 0
     iet_tx_hold: 0
     iet_tx_frag: 127

On AM64-SK (Receiver):

root@am64xx-evm:~# ethtool -S eth0 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 68
     iet_rx_smd_err: 34
     iet_rx_frag: 127
     iet_tx_hold: 0
     iet_tx_frag: 0

3.2.3.8.3.4.3.3.2. Frame sent by J7VCL with preemption on J7VCL Egress Port and Assembled on AM625-SK’s (Switch) Ingress Port followed by preemption on AM625-SK’s (Switch) Egress Port and Assembled on AM64-SK¶

Connect eth1 of J7VCL to eth0 of AM625-SK and eth0 of AM64-SK to eth1 of AM625-SK.

Steps:

Create and run the following script on AM625-SK:

#!/bin/sh

ifconfig eth0 down
ifconfig eth1 down
ethtool -L eth0 tx 2
ethtool --set-priv-flags eth0 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth0 iet-frame-preemption on
ethtool --set-priv-flags eth0 iet-mac-verify on
ethtool -L eth1 tx 2
ethtool --set-priv-flags eth1 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth1 iet-frame-preemption on
ethtool --set-priv-flags eth1 iet-mac-verify on
ifconfig eth0 up
ifconfig eth1 up
sleep 5

tc qdisc replace dev eth1 handle 100: parent root mqprio \
    num_tc 2 \
    map 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 \
    queues 1@0 1@1 \
    hw 0

tc -g class show dev eth1

devlink dev param set platform/8000000.ethernet name switch_mode value true cmode runtime
ip link add name br0 type bridge
ip link set dev br0 type bridge ageing_time 1000
ip link set dev eth0 up
ip link set dev eth1 up
ip link set dev eth0 master br0
ip link set dev eth1 master br0
ip link set dev br0 up
sleep 2

ip link set dev br0 type bridge vlan_filtering 1
bridge vlan add dev br0 vid 100 pvid tagged self
bridge vlan add dev eth0 vid 100 master
bridge vlan add dev eth1 vid 100 master
sleep 2

ip link add link br0 name br0.100 type vlan id 100
ip link set br0.100 type vlan egress 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
sleep 2

tc qdisc add dev br0.100 clsact
tc filter add dev br0.100 egress protocol ip prio 1 u32 match ip dport 5002 0xffff action skbedit priority 2
sleep 2

Create and run the following script on AM64-SK:

#!/bin/sh

ifconfig eth0 down
ifconfig eth1 down
ethtool -L eth0 tx 2
ethtool --set-priv-flags eth0 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth0 iet-frame-preemption on
ethtool --set-priv-flags eth0 iet-mac-verify on
ifconfig eth0 up
sleep 5

ip link add link eth0 name eth0.100 type vlan id 100
sleep 5
ifconfig eth0.100 192.168.100.30
iperf3 -s -i30 -p5001&
iperf3 -s -i30 -p5002&
iperf3 -s -i30 -p5003&
iperf3 -s -i30 -p5004&
iperf3 -s -i30 -p5005&

Create and run the following script on J7VCL:

#!/bin/sh

ifconfig eth1 down
ifconfig eth2 down
ifconfig eth3 down
ifconfig eth4 down
ethtool -L eth1 tx 2
ethtool --set-priv-flags eth1 p0-rx-ptype-rrobin off
ethtool --set-priv-flags eth1 iet-frame-preemption on
ethtool --set-priv-flags eth1 iet-mac-verify on
ifconfig eth1 up
sleep 5
ip link add link eth1 name eth1.100 type vlan id 100
ip link set eth1.100 type vlan egress 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
sleep 5

tc qdisc add dev eth1.100 clsact
tc filter add dev eth1.100 egress protocol ip prio 1 u32 match ip dport 5003 0xffff action skbedit priority 2
tc filter add dev eth1.100 egress protocol ip prio 1 u32 match ip dport 5004 0xffff action skbedit priority 3
ifconfig eth1.100 192.168.100.20 netmask 255.255.255.0
sleep 2

Run the following commands on AM625-SK:

ifconfig br0.100 192.168.100.10
sleep 10
iperf3 -c 192.168.100.30 -u -b100M -l1472 t30 -i30 -p5001& \
iperf3 -c 192.168.100.30 -u -b100M -l1472 t30 -i30 -p5002&

Now, run the following commands on J7VCL:

iperf3 -c 192.168.100.30 -u -b100M -l1472 -t30 -i30 -p5003& \
iperf3 -c 192.168.100.30 -u -b50M -l1472 -t30 -i30 -p5004& \
iperf3 -c 192.168.100.30 -u -b100M -l1472 -t30 -i30 -p5005&

Results:

On J7VCL (Sender):

root@j7200-evm:~/IET# ethtool -S eth1 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 0
     iet_rx_smd_err: 55
     iet_rx_frag: 0
     iet_tx_hold: 0
     iet_tx_frag: 220

On AM625-SK (Switch):

root@am62xx-evm:~/IET# ethtool -S eth0 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 106
     iet_rx_smd_err: 4
     iet_rx_frag: 220
     iet_tx_hold: 0
     iet_tx_frag: 0
root@am62xx-evm:~/IET# ethtool -S eth1 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 0
     iet_rx_smd_err: 0
     iet_rx_frag: 0
     iet_tx_hold: 0
     iet_tx_frag: 212

On AM64-SK (Receiver):

root@am64xx-evm:~# ethtool -S eth0 | grep iet
     iet_rx_assembly_err: 0
     iet_rx_assembly_ok: 148
     iet_rx_smd_err: 109
     iet_rx_frag: 212
     iet_tx_hold: 0
     iet_tx_frag: 0