selftests: ethtool: add a netdevsim FEC test

Test FEC settings, iterate over configs.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/drivers/net/netdevsim/ethtool-common.sh

@@ -24,8 +24,11 @@ function check {
     local code=$1
     local str=$2
     local exp_str=$3
+    local exp_fail=$4
 
-    if [ $code -ne 0 ]; then
+    [ -z "$exp_fail" ] && cop="-ne" || cop="-eq"
+
+    if [ $code $cop 0 ]; then
 	((num_errors++))
 	return
     fi

tools/testing/selftests/drivers/net/netdevsim/ethtool-fec.sh

+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0-only
+
+source ethtool-common.sh
+
+NSIM_NETDEV=$(make_netdev)
+[ a$ETHTOOL == a ] && ETHTOOL=ethtool
+
+set -o pipefail
+
+# netdevsim starts out with None/None
+s=$($ETHTOOL --show-fec $NSIM_NETDEV | tail -2)
+check $? "$s" "Configured FEC encodings: None
+Active FEC encoding: None"
+
+# Test Auto
+$ETHTOOL --set-fec $NSIM_NETDEV encoding auto
+check $?
+s=$($ETHTOOL --show-fec $NSIM_NETDEV | tail -2)
+check $? "$s" "Configured FEC encodings: Auto
+Active FEC encoding: Off"
+
+# Test case in-sensitivity
+for o in off Off OFF; do
+    $ETHTOOL --set-fec $NSIM_NETDEV encoding $o
+    check $?
+    s=$($ETHTOOL --show-fec $NSIM_NETDEV | tail -2)
+    check $? "$s" "Configured FEC encodings: Off
+Active FEC encoding: Off"
+done
+
+for o in BaseR baser BAser; do
+    $ETHTOOL --set-fec $NSIM_NETDEV encoding $o
+    check $?
+    s=$($ETHTOOL --show-fec $NSIM_NETDEV | tail -2)
+    check $? "$s" "Configured FEC encodings: BaseR
+Active FEC encoding: BaseR"
+done
+
+for o in llrs rs; do
+    $ETHTOOL --set-fec $NSIM_NETDEV encoding $o
+    check $?
+    s=$($ETHTOOL --show-fec $NSIM_NETDEV | tail -2)
+    check $? "$s" "Configured FEC encodings: ${o^^}
+Active FEC encoding: ${o^^}"
+done
+
+# Test mutliple bits
+$ETHTOOL --set-fec $NSIM_NETDEV encoding rs llrs
+check $?
+s=$($ETHTOOL --show-fec $NSIM_NETDEV | tail -2)
+check $? "$s" "Configured FEC encodings: RS LLRS
+Active FEC encoding: LLRS"
+
+$ETHTOOL --set-fec $NSIM_NETDEV encoding rs off auto
+check $?
+s=$($ETHTOOL --show-fec $NSIM_NETDEV | tail -2)
+check $? "$s" "Configured FEC encodings: Auto Off RS
+Active FEC encoding: RS"
+
+# Make sure other link modes are rejected
+$ETHTOOL --set-fec $NSIM_NETDEV encoding FIBRE 2>/dev/null
+check $? '' '' 1
+
+$ETHTOOL --set-fec $NSIM_NETDEV encoding bla-bla-bla 2>/dev/null
+check $? '' '' 1
+
+# Try JSON
+$ETHTOOL --json --show-fec $NSIM_NETDEV | jq empty >>/dev/null 2>&1
+if [ $? -eq 0 ]; then
+    $ETHTOOL --set-fec $NSIM_NETDEV encoding auto
+    check $?
+
+    s=$($ETHTOOL --json --show-fec $NSIM_NETDEV | jq '.[].config[]')
+    check $? "$s" '"Auto"'
+    s=$($ETHTOOL --json --show-fec $NSIM_NETDEV | jq '.[].active[]')
+    check $? "$s" '"Off"'
+
+    $ETHTOOL --set-fec $NSIM_NETDEV encoding auto RS
+    check $?
+
+    s=$($ETHTOOL --json --show-fec $NSIM_NETDEV | jq '.[].config[]')
+    check $? "$s" '"Auto"
+"RS"'
+    s=$($ETHTOOL --json --show-fec $NSIM_NETDEV | jq '.[].active[]')
+    check $? "$s" '"RS"'
+fi
+
+# Test error injection
+echo 11 > $NSIM_DEV_DFS/ethtool/get_err
+
+$ETHTOOL --show-fec $NSIM_NETDEV >>/dev/null 2>&1
+check $? '' '' 1
+
+echo 0 > $NSIM_DEV_DFS/ethtool/get_err
+echo 11 > $NSIM_DEV_DFS/ethtool/set_err
+
+$ETHTOOL --show-fec $NSIM_NETDEV  >>/dev/null 2>&1
+check $?
+
+$ETHTOOL --set-fec $NSIM_NETDEV encoding RS 2>/dev/null
+check $? '' '' 1
+
+if [ $num_errors -eq 0 ]; then
+    echo "PASSED all $((num_passes)) checks"
+    exit 0
+else
+    echo "FAILED $num_errors/$((num_errors+num_passes)) checks"
+    exit 1
+fi