net: selftests: Add lanes setting test

Test that setting lanes parameter is working.

Set max speed and max lanes in the list of advertised link modes,
and then try to set max speed with the lanes below max lanes if exists
in the list.

And then, test that setting number of lanes larger than max lanes fails.

Do the above for both autoneg on and off.

$ ./ethtool_lanes.sh

TEST: 4 lanes is autonegotiated                                     [ OK ]
TEST: Lanes number larger than max width is not set                 [ OK ]
TEST: Autoneg off, 4 lanes detected during force mode               [ OK ]
TEST: Lanes number larger than max width is not set                 [ OK ]
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

tools/testing/selftests/drivers/net/mlxsw/ethtool_lanes.sh

+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+lib_dir=$(dirname $0)/../../../net/forwarding
+
+ALL_TESTS="
+	autoneg
+	autoneg_force_mode
+"
+
+NUM_NETIFS=2
+: ${TIMEOUT:=30000} # ms
+source $lib_dir/lib.sh
+source $lib_dir/ethtool_lib.sh
+
+setup_prepare()
+{
+	swp1=${NETIFS[p1]}
+	swp2=${NETIFS[p2]}
+
+	ip link set dev $swp1 up
+	ip link set dev $swp2 up
+
+	busywait "$TIMEOUT" wait_for_port_up ethtool $swp2
+	check_err $? "ports did not come up"
+
+	local lanes_exist=$(ethtool $swp1 | grep 'Lanes:')
+	if [[ -z $lanes_exist ]]; then
+		log_test "SKIP: driver does not support lanes setting"
+		exit 1
+	fi
+
+	ip link set dev $swp2 down
+	ip link set dev $swp1 down
+}
+
+check_lanes()
+{
+	local dev=$1; shift
+	local lanes=$1; shift
+	local max_speed=$1; shift
+	local chosen_lanes
+
+	chosen_lanes=$(ethtool $dev | grep 'Lanes:')
+	chosen_lanes=${chosen_lanes#*"Lanes: "}
+
+	((chosen_lanes == lanes))
+	check_err $? "swp1 advertise $max_speed and $lanes, devs sync to $chosen_lanes"
+}
+
+check_unsupported_lanes()
+{
+	local dev=$1; shift
+	local max_speed=$1; shift
+	local max_lanes=$1; shift
+	local autoneg=$1; shift
+	local autoneg_str=""
+
+	local unsupported_lanes=$((max_lanes *= 2))
+
+	if [[ $autoneg -eq 0 ]]; then
+		autoneg_str="autoneg off"
+	fi
+
+	ethtool -s $swp1 speed $max_speed lanes $unsupported_lanes $autoneg_str &> /dev/null
+	check_fail $? "Unsuccessful $unsupported_lanes lanes setting was expected"
+}
+
+max_speed_and_lanes_get()
+{
+	local dev=$1; shift
+	local arr=("$@")
+	local max_lanes
+	local max_speed
+	local -a lanes_arr
+	local -a speeds_arr
+	local -a max_values
+
+	for ((i=0; i<${#arr[@]}; i+=2)); do
+		speeds_arr+=("${arr[$i]}")
+		lanes_arr+=("${arr[i+1]}")
+	done
+
+	max_values+=($(get_max "${speeds_arr[@]}"))
+	max_values+=($(get_max "${lanes_arr[@]}"))
+
+	echo ${max_values[@]}
+}
+
+search_linkmode()
+{
+	local speed=$1; shift
+	local lanes=$1; shift
+	local arr=("$@")
+
+	for ((i=0; i<${#arr[@]}; i+=2)); do
+		if [[ $speed -eq ${arr[$i]} && $lanes -eq ${arr[i+1]} ]]; then
+			return 1
+		fi
+	done
+	return 0
+}
+
+autoneg()
+{
+	RET=0
+
+	local lanes
+	local max_speed
+	local max_lanes
+
+	local -a linkmodes_params=($(dev_linkmodes_params_get $swp1 1))
+	local -a max_values=($(max_speed_and_lanes_get $swp1 "${linkmodes_params[@]}"))
+	max_speed=${max_values[0]}
+	max_lanes=${max_values[1]}
+
+	lanes=$max_lanes
+
+	while [[ $lanes -ge 1 ]]; do
+		search_linkmode $max_speed $lanes "${linkmodes_params[@]}"
+		if [[ $? -eq 1 ]]; then
+			ethtool_set $swp1 speed $max_speed lanes $lanes
+			ip link set dev $swp1 up
+			ip link set dev $swp2 up
+			busywait "$TIMEOUT" wait_for_port_up ethtool $swp2
+			check_err $? "ports did not come up"
+
+			check_lanes $swp1 $lanes $max_speed
+			log_test "$lanes lanes is autonegotiated"
+		fi
+		let $((lanes /= 2))
+	done
+
+	check_unsupported_lanes $swp1 $max_speed $max_lanes 1
+	log_test "Lanes number larger than max width is not set"
+
+	ip link set dev $swp2 down
+	ip link set dev $swp1 down
+}
+
+autoneg_force_mode()
+{
+	RET=0
+
+	local lanes
+	local max_speed
+	local max_lanes
+
+	local -a linkmodes_params=($(dev_linkmodes_params_get $swp1 1))
+	local -a max_values=($(max_speed_and_lanes_get $swp1 "${linkmodes_params[@]}"))
+	max_speed=${max_values[0]}
+	max_lanes=${max_values[1]}
+
+	lanes=$max_lanes
+
+	while [[ $lanes -ge 1 ]]; do
+		search_linkmode $max_speed $lanes "${linkmodes_params[@]}"
+		if [[ $? -eq 1 ]]; then
+			ethtool_set $swp1 speed $max_speed lanes $lanes autoneg off
+			ethtool_set $swp2 speed $max_speed lanes $lanes autoneg off
+			ip link set dev $swp1 up
+			ip link set dev $swp2 up
+			busywait "$TIMEOUT" wait_for_port_up ethtool $swp2
+			check_err $? "ports did not come up"
+
+			check_lanes $swp1 $lanes $max_speed
+			log_test "Autoneg off, $lanes lanes detected during force mode"
+		fi
+		let $((lanes /= 2))
+	done
+
+	check_unsupported_lanes $swp1 $max_speed $max_lanes 0
+	log_test "Lanes number larger than max width is not set"
+
+	ip link set dev $swp2 down
+	ip link set dev $swp1 down
+
+	ethtool -s $swp2 autoneg on
+	ethtool -s $swp1 autoneg on
+}
+
+check_ethtool_lanes_support
+setup_prepare
+
+tests_run
+
+exit $EXIT_STATUS

tools/testing/selftests/net/forwarding/ethtool_lib.sh

@@ -22,6 +22,40 @@ ethtool_set()
 	check_err $out "error in configuration. $cmd"
 }
 
+dev_linkmodes_params_get()
+{
+	local dev=$1; shift
+	local adver=$1; shift
+	local -a linkmodes_params
+	local param_count
+	local arr
+
+	if (($adver)); then
+		mode="Advertised link modes"
+	else
+		mode="Supported link modes"
+	fi
+
+	local -a dev_linkmodes=($(dev_speeds_get $dev 1 $adver))
+	for ((i=0; i<${#dev_linkmodes[@]}; i++)); do
+		linkmodes_params[$i]=$(echo -e "${dev_linkmodes[$i]}" | \
+			# Replaces all non numbers with spaces
+			sed -e 's/[^0-9]/ /g' | \
+			# Squeeze spaces in sequence to 1 space
+			tr -s ' ')
+		# Count how many numbers were found in the linkmode
+		param_count=$(echo "${linkmodes_params[$i]}" | wc -w)
+		if [[ $param_count -eq 1 ]]; then
+			linkmodes_params[$i]="${linkmodes_params[$i]} 1"
+		elif [[ $param_count -ge 3 ]]; then
+			arr=(${linkmodes_params[$i]})
+			# Take only first two params
+			linkmodes_params[$i]=$(echo "${arr[@]:0:2}")
+		fi
+	done
+	echo ${linkmodes_params[@]}
+}
+
 dev_speeds_get()
 {
 	local dev=$1; shift

tools/testing/selftests/net/forwarding/lib.sh

@@ -69,6 +69,15 @@ check_tc_action_hw_stats_support()
 	fi
 }
 
+check_ethtool_lanes_support()
+{
+	ethtool --help 2>&1| grep lanes &> /dev/null
+	if [[ $? -ne 0 ]]; then
+		echo "SKIP: ethtool too old; it is missing lanes support"
+		exit 1
+	fi
+}
+
 if [[ "$(id -u)" -ne 0 ]]; then
 	echo "SKIP: need root privileges"
 	exit 0
@@ -263,6 +272,20 @@ not()
 	[[ $? != 0 ]]
 }
 
+get_max()
+{
+	local arr=("$@")
+
+	max=${arr[0]}
+	for cur in ${arr[@]}; do
+		if [[ $cur -gt $max ]]; then
+			max=$cur
+		fi
+	done
+
+	echo $max
+}
+
 grep_bridge_fdb()
 {
 	local addr=$1; shift
@@ -279,6 +302,11 @@ grep_bridge_fdb()
 	$@ | grep $addr | grep $flag "$word"
 }
 
+wait_for_port_up()
+{
+	"$@" | grep -q "Link detected: yes"
+}
+
 wait_for_offload()
 {
 	"$@" | grep -q offload