Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

8 files changed, 1063 insertions, 0 deletions

diff --git a/tools/testing/selftests/cpufreq/Makefile b/tools/testing/selftests/cpufreq/Makefile
new file mode 100644
index 000000000..c86ca8342
--- /dev/null
+++ b/tools/testing/selftests/cpufreq/Makefile
@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-2.0
+all:
+
+TEST_PROGS := main.sh
+TEST_FILES := cpu.sh cpufreq.sh governor.sh module.sh special-tests.sh
+
+include ../lib.mk
+
+clean:
diff --git a/tools/testing/selftests/cpufreq/config b/tools/testing/selftests/cpufreq/config
new file mode 100644
index 000000000..27ff72ebd
--- /dev/null
+++ b/tools/testing/selftests/cpufreq/config
@@ -0,0 +1,15 @@
+CONFIG_CPU_FREQ=y
+CONFIG_CPU_FREQ_STAT=y
+CONFIG_CPU_FREQ_GOV_POWERSAVE=y
+CONFIG_CPU_FREQ_GOV_USERSPACE=y
+CONFIG_CPU_FREQ_GOV_ONDEMAND=y
+CONFIG_CPU_FREQ_GOV_CONSERVATIVE=y
+CONFIG_CPU_FREQ_GOV_SCHEDUTIL=y
+CONFIG_DEBUG_RT_MUTEXES=y
+CONFIG_DEBUG_PI_LIST=y
+CONFIG_DEBUG_SPINLOCK=y
+CONFIG_DEBUG_MUTEXES=y
+CONFIG_DEBUG_LOCK_ALLOC=y
+CONFIG_PROVE_LOCKING=y
+CONFIG_LOCKDEP=y
+CONFIG_DEBUG_ATOMIC_SLEEP=y
diff --git a/tools/testing/selftests/cpufreq/cpu.sh b/tools/testing/selftests/cpufreq/cpu.sh
new file mode 100755
index 000000000..39fdcdfb8
--- /dev/null
+++ b/tools/testing/selftests/cpufreq/cpu.sh
@@ -0,0 +1,85 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# CPU helpers
+
+# protect against multiple inclusion
+if [ $FILE_CPU ]; then
+	return 0
+else
+	FILE_CPU=DONE
+fi
+
+source cpufreq.sh
+
+for_each_cpu()
+{
+	cpus=$(ls $CPUROOT | grep "cpu[0-9].*")
+	for cpu in $cpus; do
+		$@ $cpu
+	done
+}
+
+for_each_non_boot_cpu()
+{
+	cpus=$(ls $CPUROOT | grep "cpu[1-9].*")
+	for cpu in $cpus; do
+		$@ $cpu
+	done
+}
+
+#$1: cpu
+offline_cpu()
+{
+	printf "Offline $1\n"
+	echo 0 > $CPUROOT/$1/online
+}
+
+#$1: cpu
+online_cpu()
+{
+	printf "Online $1\n"
+	echo 1 > $CPUROOT/$1/online
+}
+
+#$1: cpu
+reboot_cpu()
+{
+	offline_cpu $1
+	online_cpu $1
+}
+
+# Reboot CPUs
+# param: number of times we want to run the loop
+reboot_cpus()
+{
+	printf "** Test: Running ${FUNCNAME[0]} for $1 loops **\n\n"
+
+	for i in `seq 1 $1`; do
+		for_each_non_boot_cpu offline_cpu
+		for_each_non_boot_cpu online_cpu
+		printf "\n"
+	done
+
+	printf "\n%s\n\n" "------------------------------------------------"
+}
+
+# Prints warning for all CPUs with missing cpufreq directory
+print_unmanaged_cpus()
+{
+	for_each_cpu cpu_should_have_cpufreq_directory
+}
+
+# Counts CPUs with cpufreq directories
+count_cpufreq_managed_cpus()
+{
+	count=0;
+
+	for cpu in `ls $CPUROOT | grep "cpu[0-9].*"`; do
+		if [ -d $CPUROOT/$cpu/cpufreq ]; then
+			let count=count+1;
+		fi
+	done
+
+	echo $count;
+}
diff --git a/tools/testing/selftests/cpufreq/cpufreq.sh b/tools/testing/selftests/cpufreq/cpufreq.sh
new file mode 100755
index 000000000..b583a2fb4
--- /dev/null
+++ b/tools/testing/selftests/cpufreq/cpufreq.sh
@@ -0,0 +1,242 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+# protect against multiple inclusion
+if [ $FILE_CPUFREQ ]; then
+	return 0
+else
+	FILE_CPUFREQ=DONE
+fi
+
+source cpu.sh
+
+
+# $1: cpu
+cpu_should_have_cpufreq_directory()
+{
+	if [ ! -d $CPUROOT/$1/cpufreq ]; then
+		printf "Warning: No cpufreq directory present for $1\n"
+	fi
+}
+
+cpu_should_not_have_cpufreq_directory()
+{
+	if [ -d $CPUROOT/$1/cpufreq ]; then
+		printf "Warning: cpufreq directory present for $1\n"
+	fi
+}
+
+for_each_policy()
+{
+	policies=$(ls $CPUFREQROOT| grep "policy[0-9].*")
+	for policy in $policies; do
+		$@ $policy
+	done
+}
+
+for_each_policy_concurrent()
+{
+	policies=$(ls $CPUFREQROOT| grep "policy[0-9].*")
+	for policy in $policies; do
+		$@ $policy &
+	done
+}
+
+# $1: Path
+read_cpufreq_files_in_dir()
+{
+	local files=`ls $1`
+
+	printf "Printing directory: $1\n\n"
+
+	for file in $files; do
+		if [ -f $1/$file ]; then
+			printf "$file:"
+			cat $1/$file
+		else
+			printf "\n"
+			read_cpufreq_files_in_dir "$1/$file"
+		fi
+	done
+	printf "\n"
+}
+
+
+read_all_cpufreq_files()
+{
+	printf "** Test: Running ${FUNCNAME[0]} **\n\n"
+
+	read_cpufreq_files_in_dir $CPUFREQROOT
+
+	printf "%s\n\n" "------------------------------------------------"
+}
+
+
+# UPDATE CPUFREQ FILES
+
+# $1: directory path
+update_cpufreq_files_in_dir()
+{
+	local files=`ls $1`
+
+	printf "Updating directory: $1\n\n"
+
+	for file in $files; do
+		if [ -f $1/$file ]; then
+			# file is writable ?
+			local wfile=$(ls -l $1/$file | awk '$1 ~ /^.*w.*/ { print $NF; }')
+
+			if [ ! -z $wfile ]; then
+				# scaling_setspeed is a special file and we
+				# should skip updating it
+				if [ $file != "scaling_setspeed" ]; then
+					local val=$(cat $1/$file)
+					printf "Writing $val to: $file\n"
+					echo $val > $1/$file
+				fi
+			fi
+		else
+			printf "\n"
+			update_cpufreq_files_in_dir "$1/$file"
+		fi
+	done
+
+	printf "\n"
+}
+
+# Update all writable files with their existing values
+update_all_cpufreq_files()
+{
+	printf "** Test: Running ${FUNCNAME[0]} **\n\n"
+
+	update_cpufreq_files_in_dir $CPUFREQROOT
+
+	printf "%s\n\n" "------------------------------------------------"
+}
+
+
+# CHANGE CPU FREQUENCIES
+
+# $1: policy
+find_current_freq()
+{
+	cat $CPUFREQROOT/$1/scaling_cur_freq
+}
+
+# $1: policy
+# $2: frequency
+set_cpu_frequency()
+{
+	printf "Change frequency for $1 to $2\n"
+	echo $2 > $CPUFREQROOT/$1/scaling_setspeed
+}
+
+# $1: policy
+test_all_frequencies()
+{
+	local filepath="$CPUFREQROOT/$1"
+
+	backup_governor $1
+
+	local found=$(switch_governor $1 "userspace")
+	if [ $found = 1 ]; then
+		printf "${FUNCNAME[0]}: userspace governor not available for: $1\n"
+		return;
+	fi
+
+	printf "Switched governor for $1 to userspace\n\n"
+
+	local freqs=$(cat $filepath/scaling_available_frequencies)
+	printf "Available frequencies for $1: $freqs\n\n"
+
+	# Set all frequencies one-by-one
+	for freq in $freqs; do
+		set_cpu_frequency $1 $freq
+	done
+
+	printf "\n"
+
+	restore_governor $1
+}
+
+# $1: loop count
+shuffle_frequency_for_all_cpus()
+{
+	printf "** Test: Running ${FUNCNAME[0]} for $1 loops **\n\n"
+
+	for i in `seq 1 $1`; do
+		for_each_policy test_all_frequencies
+	done
+	printf "\n%s\n\n" "------------------------------------------------"
+}
+
+# Basic cpufreq tests
+cpufreq_basic_tests()
+{
+	printf "*** RUNNING CPUFREQ SANITY TESTS ***\n"
+	printf "====================================\n\n"
+
+	count=$(count_cpufreq_managed_cpus)
+	if [ $count = 0 ]; then
+		printf "No cpu is managed by cpufreq core, exiting\n"
+		exit;
+	else
+		printf "CPUFreq manages: $count CPUs\n\n"
+	fi
+
+	# Detect & print which CPUs are not managed by cpufreq
+	print_unmanaged_cpus
+
+	# read/update all cpufreq files
+	read_all_cpufreq_files
+	update_all_cpufreq_files
+
+	# hotplug cpus
+	reboot_cpus 5
+
+	# Test all frequencies
+	shuffle_frequency_for_all_cpus 2
+
+	# Test all governors
+	shuffle_governors_for_all_cpus 1
+}
+
+# Suspend/resume
+# $1: "suspend" or "hibernate", $2: loop count
+do_suspend()
+{
+	printf "** Test: Running ${FUNCNAME[0]}: Trying $1 for $2 loops **\n\n"
+
+	# Is the directory available
+	if [ ! -d $SYSFS/power/ -o ! -f $SYSFS/power/state ]; then
+		printf "$SYSFS/power/state not available\n"
+		return 1
+	fi
+
+	if [ $1 = "suspend" ]; then
+		filename="mem"
+	elif [ $1 = "hibernate" ]; then
+		filename="disk"
+	else
+		printf "$1 is not a valid option\n"
+		return 1
+	fi
+
+	if [ -n $filename ]; then
+		present=$(cat $SYSFS/power/state | grep $filename)
+
+		if [ -z "$present" ]; then
+			printf "Tried to $1 but $filename isn't present in $SYSFS/power/state\n"
+			return 1;
+		fi
+
+		for i in `seq 1 $2`; do
+			printf "Starting $1\n"
+			echo $filename > $SYSFS/power/state
+			printf "Came out of $1\n"
+
+			printf "Do basic tests after finishing $1 to verify cpufreq state\n\n"
+			cpufreq_basic_tests
+		done
+	fi
+}
diff --git a/tools/testing/selftests/cpufreq/governor.sh b/tools/testing/selftests/cpufreq/governor.sh
new file mode 100755
index 000000000..fe37df79c
--- /dev/null
+++ b/tools/testing/selftests/cpufreq/governor.sh
@@ -0,0 +1,154 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Test governors
+
+# protect against multiple inclusion
+if [ $FILE_GOVERNOR ]; then
+	return 0
+else
+	FILE_GOVERNOR=DONE
+fi
+
+source cpu.sh
+source cpufreq.sh
+
+CUR_GOV=
+CUR_FREQ=
+
+# Find governor's directory path
+# $1: policy, $2: governor
+find_gov_directory()
+{
+	if [ -d $CPUFREQROOT/$2 ]; then
+		printf "$CPUFREQROOT/$2\n"
+	elif [ -d $CPUFREQROOT/$1/$2 ]; then
+		printf "$CPUFREQROOT/$1/$2\n"
+	else
+		printf "INVALID\n"
+	fi
+}
+
+# $1: policy
+find_current_governor()
+{
+	cat $CPUFREQROOT/$1/scaling_governor
+}
+
+# $1: policy
+backup_governor()
+{
+	CUR_GOV=$(find_current_governor $1)
+
+	printf "Governor backup done for $1: $CUR_GOV\n"
+
+	if [ $CUR_GOV == "userspace" ]; then
+		CUR_FREQ=$(find_current_freq $1)
+		printf "Governor frequency backup done for $1: $CUR_FREQ\n"
+	fi
+
+	printf "\n"
+}
+
+# $1: policy
+restore_governor()
+{
+	__switch_governor $1 $CUR_GOV
+
+	printf "Governor restored for $1 to $CUR_GOV\n"
+
+	if [ $CUR_GOV == "userspace" ]; then
+		set_cpu_frequency $1 $CUR_FREQ
+		printf "Governor frequency restored for $1: $CUR_FREQ\n"
+	fi
+
+	printf "\n"
+}
+
+# param:
+# $1: policy, $2: governor
+__switch_governor()
+{
+	echo $2 > $CPUFREQROOT/$1/scaling_governor
+}
+
+# param:
+# $1: cpu, $2: governor
+__switch_governor_for_cpu()
+{
+	echo $2 > $CPUROOT/$1/cpufreq/scaling_governor
+}
+
+# SWITCH GOVERNORS
+
+# $1: cpu, $2: governor
+switch_governor()
+{
+	local filepath=$CPUFREQROOT/$1/scaling_available_governors
+
+	# check if governor is available
+	local found=$(cat $filepath | grep $2 | wc -l)
+	if [ $found = 0 ]; then
+		echo 1;
+		return
+	fi
+
+	__switch_governor $1 $2
+	echo 0;
+}
+
+# $1: policy, $2: governor
+switch_show_governor()
+{
+	cur_gov=find_current_governor
+	if [ $cur_gov == "userspace" ]; then
+		cur_freq=find_current_freq
+	fi
+
+	# switch governor
+	__switch_governor $1 $2
+
+	printf "\nSwitched governor for $1 to $2\n\n"
+
+	if [ $2 == "userspace" -o $2 == "powersave" -o $2 == "performance" ]; then
+		printf "No files to read for $2 governor\n\n"
+		return
+	fi
+
+	# show governor files
+	local govpath=$(find_gov_directory $1 $2)
+	read_cpufreq_files_in_dir $govpath
+}
+
+# $1: function to be called, $2: policy
+call_for_each_governor()
+{
+	local filepath=$CPUFREQROOT/$2/scaling_available_governors
+
+	# Exit if cpu isn't managed by cpufreq core
+	if [ ! -f $filepath ]; then
+		return;
+	fi
+
+	backup_governor $2
+
+	local governors=$(cat $filepath)
+	printf "Available governors for $2: $governors\n"
+
+	for governor in $governors; do
+		$1 $2 $governor
+	done
+
+	restore_governor $2
+}
+
+# $1: loop count
+shuffle_governors_for_all_cpus()
+{
+	printf "** Test: Running ${FUNCNAME[0]} for $1 loops **\n\n"
+
+	for i in `seq 1 $1`; do
+		for_each_policy call_for_each_governor switch_show_governor
+	done
+	printf "%s\n\n" "------------------------------------------------"
+}
diff --git a/tools/testing/selftests/cpufreq/main.sh b/tools/testing/selftests/cpufreq/main.sh
new file mode 100755
index 000000000..31f8c9a76
--- /dev/null
+++ b/tools/testing/selftests/cpufreq/main.sh
@@ -0,0 +1,198 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+source cpu.sh
+source cpufreq.sh
+source governor.sh
+source module.sh
+source special-tests.sh
+
+FUNC=basic	# do basic tests by default
+OUTFILE=cpufreq_selftest
+SYSFS=
+CPUROOT=
+CPUFREQROOT=
+
+# Kselftest framework requirement - SKIP code is 4.
+ksft_skip=4
+
+helpme()
+{
+	printf "Usage: $0 [-h] [-todg args]
+	[-h <help>]
+	[-o <output-file-for-dump>]
+	[-t <basic: Basic cpufreq testing
+	     suspend: suspend/resume,
+	     hibernate: hibernate/resume,
+	     modtest: test driver or governor modules. Only to be used with -d or -g options,
+	     sptest1: Simple governor switch to produce lockdep.
+	     sptest2: Concurrent governor switch to produce lockdep.
+	     sptest3: Governor races, shuffle between governors quickly.
+	     sptest4: CPU hotplugs with updates to cpufreq files.>]
+	[-d <driver's module name: only with \"-t modtest>\"]
+	[-g <governor's module name: only with \"-t modtest>\"]
+	\n"
+	exit 2
+}
+
+prerequisite()
+{
+	msg="skip all tests:"
+
+	if [ $UID != 0 ]; then
+		echo $msg must be run as root >&2
+		exit $ksft_skip
+	fi
+
+	taskset -p 01 $$
+
+	SYSFS=`mount -t sysfs | head -1 | awk '{ print $3 }'`
+
+	if [ ! -d "$SYSFS" ]; then
+		echo $msg sysfs is not mounted >&2
+		exit 2
+	fi
+
+	CPUROOT=$SYSFS/devices/system/cpu
+	CPUFREQROOT="$CPUROOT/cpufreq"
+
+	if ! ls $CPUROOT/cpu* > /dev/null 2>&1; then
+		echo $msg cpus not available in sysfs >&2
+		exit 2
+	fi
+
+	if ! ls $CPUROOT/cpufreq > /dev/null 2>&1; then
+		echo $msg cpufreq directory not available in sysfs >&2
+		exit 2
+	fi
+}
+
+parse_arguments()
+{
+	while getopts ht:o:d:g: arg
+	do
+		case $arg in
+			h) # --help
+				helpme
+				;;
+
+			t) # --func_type (Function to perform: basic, suspend, hibernate, modtest, sptest1/2/3/4 (default: basic))
+				FUNC=$OPTARG
+				;;
+
+			o) # --output-file (Output file to store dumps)
+				OUTFILE=$OPTARG
+				;;
+
+			d) # --driver-mod-name (Name of the driver module)
+				DRIVER_MOD=$OPTARG
+				;;
+
+			g) # --governor-mod-name (Name of the governor module)
+				GOVERNOR_MOD=$OPTARG
+				;;
+
+			\?)
+				helpme
+				;;
+		esac
+	done
+}
+
+do_test()
+{
+	# Check if CPUs are managed by cpufreq or not
+	count=$(count_cpufreq_managed_cpus)
+
+	if [ $count = 0 -a $FUNC != "modtest" ]; then
+		echo "No cpu is managed by cpufreq core, exiting"
+		exit 2;
+	fi
+
+	case "$FUNC" in
+		"basic")
+		cpufreq_basic_tests
+		;;
+
+		"suspend")
+		do_suspend "suspend" 1
+		;;
+
+		"hibernate")
+		do_suspend "hibernate" 1
+		;;
+
+		"modtest")
+		# Do we have modules in place?
+		if [ -z $DRIVER_MOD ] && [ -z $GOVERNOR_MOD ]; then
+			echo "No driver or governor module passed with -d or -g"
+			exit 2;
+		fi
+
+		if [ $DRIVER_MOD ]; then
+			if [ $GOVERNOR_MOD ]; then
+				module_test $DRIVER_MOD $GOVERNOR_MOD
+			else
+				module_driver_test $DRIVER_MOD
+			fi
+		else
+			if [ $count = 0 ]; then
+				echo "No cpu is managed by cpufreq core, exiting"
+				exit 2;
+			fi
+
+			module_governor_test $GOVERNOR_MOD
+		fi
+		;;
+
+		"sptest1")
+		simple_lockdep
+		;;
+
+		"sptest2")
+		concurrent_lockdep
+		;;
+
+		"sptest3")
+		governor_race
+		;;
+
+		"sptest4")
+		hotplug_with_updates
+		;;
+
+		*)
+		echo "Invalid [-f] function type"
+		helpme
+		;;
+	esac
+}
+
+# clear dumps
+# $1: file name
+clear_dumps()
+{
+	echo "" > $1.txt
+	echo "" > $1.dmesg_cpufreq.txt
+	echo "" > $1.dmesg_full.txt
+}
+
+# $1: output file name
+dmesg_dumps()
+{
+	dmesg | grep cpufreq >> $1.dmesg_cpufreq.txt
+
+	# We may need the full logs as well
+	dmesg >> $1.dmesg_full.txt
+}
+
+# Parse arguments
+parse_arguments $@
+
+# Make sure all requirements are met
+prerequisite
+
+# Run requested functions
+clear_dumps $OUTFILE
+do_test >> $OUTFILE.txt
+dmesg_dumps $OUTFILE
diff --git a/tools/testing/selftests/cpufreq/module.sh b/tools/testing/selftests/cpufreq/module.sh
new file mode 100755
index 000000000..22563cd12
--- /dev/null
+++ b/tools/testing/selftests/cpufreq/module.sh
@@ -0,0 +1,244 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Modules specific tests cases
+
+# protect against multiple inclusion
+if [ $FILE_MODULE ]; then
+	return 0
+else
+	FILE_MODULE=DONE
+fi
+
+source cpu.sh
+source cpufreq.sh
+source governor.sh
+
+# Check basic insmod/rmmod
+# $1: module
+test_basic_insmod_rmmod()
+{
+	printf "** Test: Running ${FUNCNAME[0]} **\n\n"
+
+	printf "Inserting $1 module\n"
+	# insert module
+	insmod $1
+	if [ $? != 0 ]; then
+		printf "Insmod $1 failed\n"
+		exit;
+	fi
+
+	printf "Removing $1 module\n"
+	# remove module
+	rmmod $1
+	if [ $? != 0 ]; then
+		printf "rmmod $1 failed\n"
+		exit;
+	fi
+
+	printf "\n"
+}
+
+# Insert cpufreq driver module and perform basic tests
+# $1: cpufreq-driver module to insert
+# $2: If we want to play with CPUs (1) or not (0)
+module_driver_test_single()
+{
+	printf "** Test: Running ${FUNCNAME[0]} for driver $1 and cpus_hotplug=$2 **\n\n"
+
+	if [ $2 -eq 1 ]; then
+		# offline all non-boot CPUs
+		for_each_non_boot_cpu offline_cpu
+		printf "\n"
+	fi
+
+	# insert module
+	printf "Inserting $1 module\n\n"
+	insmod $1
+	if [ $? != 0 ]; then
+		printf "Insmod $1 failed\n"
+		return;
+	fi
+
+	if [ $2 -eq 1 ]; then
+		# online all non-boot CPUs
+		for_each_non_boot_cpu online_cpu
+		printf "\n"
+	fi
+
+	# run basic tests
+	cpufreq_basic_tests
+
+	# remove module
+	printf "Removing $1 module\n\n"
+	rmmod $1
+	if [ $? != 0 ]; then
+		printf "rmmod $1 failed\n"
+		return;
+	fi
+
+	# There shouldn't be any cpufreq directories now.
+	for_each_cpu cpu_should_not_have_cpufreq_directory
+	printf "\n"
+}
+
+# $1: cpufreq-driver module to insert
+module_driver_test()
+{
+	printf "** Test: Running ${FUNCNAME[0]} **\n\n"
+
+	# check if module is present or not
+	ls $1 > /dev/null
+	if [ $? != 0 ]; then
+		printf "$1: not present in `pwd` folder\n"
+		return;
+	fi
+
+	# test basic module tests
+	test_basic_insmod_rmmod $1
+
+	# Do simple module test
+	module_driver_test_single $1 0
+
+	# Remove CPUs before inserting module and then bring them back
+	module_driver_test_single $1 1
+	printf "\n"
+}
+
+# find governor name based on governor module name
+# $1: governor module name
+find_gov_name()
+{
+	if [ $1 = "cpufreq_ondemand.ko" ]; then
+		printf "ondemand"
+	elif [ $1 = "cpufreq_conservative.ko" ]; then
+		printf "conservative"
+	elif [ $1 = "cpufreq_userspace.ko" ]; then
+		printf "userspace"
+	elif [ $1 = "cpufreq_performance.ko" ]; then
+		printf "performance"
+	elif [ $1 = "cpufreq_powersave.ko" ]; then
+		printf "powersave"
+	elif [ $1 = "cpufreq_schedutil.ko" ]; then
+		printf "schedutil"
+	fi
+}
+
+# $1: governor string, $2: governor module, $3: policy
+# example: module_governor_test_single "ondemand" "cpufreq_ondemand.ko" 2
+module_governor_test_single()
+{
+	printf "** Test: Running ${FUNCNAME[0]} for $3 **\n\n"
+
+	backup_governor $3
+
+	# switch to new governor
+	printf "Switch from $CUR_GOV to $1\n"
+	switch_show_governor $3 $1
+
+	# try removing module, it should fail as governor is used
+	printf "Removing $2 module\n\n"
+	rmmod $2
+	if [ $? = 0 ]; then
+		printf "WARN: rmmod $2 succeeded even if governor is used\n"
+		insmod $2
+	else
+		printf "Pass: unable to remove $2 while it is being used\n\n"
+	fi
+
+	# switch back to old governor
+	printf "Switchback to $CUR_GOV from $1\n"
+	restore_governor $3
+	printf "\n"
+}
+
+# Insert cpufreq governor module and perform basic tests
+# $1: cpufreq-governor module to insert
+module_governor_test()
+{
+	printf "** Test: Running ${FUNCNAME[0]} **\n\n"
+
+	# check if module is present or not
+	ls $1 > /dev/null
+	if [ $? != 0 ]; then
+		printf "$1: not present in `pwd` folder\n"
+		return;
+	fi
+
+	# test basic module tests
+	test_basic_insmod_rmmod $1
+
+	# insert module
+	printf "Inserting $1 module\n\n"
+	insmod $1
+	if [ $? != 0 ]; then
+		printf "Insmod $1 failed\n"
+		return;
+	fi
+
+	# switch to new governor for each cpu
+	for_each_policy module_governor_test_single $(find_gov_name $1) $1
+
+	# remove module
+	printf "Removing $1 module\n\n"
+	rmmod $1
+	if [ $? != 0 ]; then
+		printf "rmmod $1 failed\n"
+		return;
+	fi
+	printf "\n"
+}
+
+# test modules: driver and governor
+# $1: driver module, $2: governor module
+module_test()
+{
+	printf "** Test: Running ${FUNCNAME[0]} **\n\n"
+
+	# check if modules are present or not
+	ls $1 $2 > /dev/null
+	if [ $? != 0 ]; then
+		printf "$1 or $2: is not present in `pwd` folder\n"
+		return;
+	fi
+
+	# TEST1: Insert gov after driver
+	# insert driver module
+	printf "Inserting $1 module\n\n"
+	insmod $1
+	if [ $? != 0 ]; then
+		printf "Insmod $1 failed\n"
+		return;
+	fi
+
+	# run governor tests
+	module_governor_test $2
+
+	# remove driver module
+	printf "Removing $1 module\n\n"
+	rmmod $1
+	if [ $? != 0 ]; then
+		printf "rmmod $1 failed\n"
+		return;
+	fi
+
+	# TEST2: Insert driver after governor
+	# insert governor module
+	printf "Inserting $2 module\n\n"
+	insmod $2
+	if [ $? != 0 ]; then
+		printf "Insmod $2 failed\n"
+		return;
+	fi
+
+	# run governor tests
+	module_driver_test $1
+
+	# remove driver module
+	printf "Removing $2 module\n\n"
+	rmmod $2
+	if [ $? != 0 ]; then
+		printf "rmmod $2 failed\n"
+		return;
+	fi
+}
diff --git a/tools/testing/selftests/cpufreq/special-tests.sh b/tools/testing/selftests/cpufreq/special-tests.sh
new file mode 100755
index 000000000..8d40505dc
--- /dev/null
+++ b/tools/testing/selftests/cpufreq/special-tests.sh
@@ -0,0 +1,116 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Special test cases reported by people
+
+# Testcase 1: Reported here: http://marc.info/?l=linux-pm&m=140618592709858&w=2
+
+# protect against multiple inclusion
+if [ $FILE_SPECIAL ]; then
+	return 0
+else
+	FILE_SPECIAL=DONE
+fi
+
+source cpu.sh
+source cpufreq.sh
+source governor.sh
+
+# Test 1
+# $1: policy
+__simple_lockdep()
+{
+	# switch to ondemand
+	__switch_governor $1 "ondemand"
+
+	# cat ondemand files
+	local ondir=$(find_gov_directory $1 "ondemand")
+	if [ -z $ondir ]; then
+		printf "${FUNCNAME[0]}Ondemand directory not created, quit"
+		return
+	fi
+
+	cat $ondir/*
+
+	# switch to conservative
+	__switch_governor $1 "conservative"
+}
+
+simple_lockdep()
+{
+	printf "** Test: Running ${FUNCNAME[0]} **\n"
+
+	for_each_policy __simple_lockdep
+}
+
+# Test 2
+# $1: policy
+__concurrent_lockdep()
+{
+	for i in `seq 0 100`; do
+		__simple_lockdep $1
+	done
+}
+
+concurrent_lockdep()
+{
+	printf "** Test: Running ${FUNCNAME[0]} **\n"
+
+	for_each_policy_concurrent __concurrent_lockdep
+}
+
+# Test 3
+quick_shuffle()
+{
+	# this is called concurrently from governor_race
+	for I in `seq 1000`
+	do
+		echo ondemand | sudo tee $CPUFREQROOT/policy*/scaling_governor &
+		echo userspace | sudo tee $CPUFREQROOT/policy*/scaling_governor &
+	done
+}
+
+governor_race()
+{
+	printf "** Test: Running ${FUNCNAME[0]} **\n"
+
+	# run 8 concurrent instances
+	for I in `seq 8`
+	do
+		quick_shuffle &
+	done
+}
+
+# Test 4
+# $1: cpu
+hotplug_with_updates_cpu()
+{
+	local filepath="$CPUROOT/$1/cpufreq"
+
+	# switch to ondemand
+	__switch_governor_for_cpu $1 "ondemand"
+
+	for i in `seq 1 5000`
+	do
+		reboot_cpu $1
+	done &
+
+	local freqs=$(cat $filepath/scaling_available_frequencies)
+	local oldfreq=$(cat $filepath/scaling_min_freq)
+
+	for j in `seq 1 5000`
+	do
+		# Set all frequencies one-by-one
+		for freq in $freqs; do
+			echo $freq > $filepath/scaling_min_freq
+		done
+	done
+
+	# restore old freq
+	echo $oldfreq > $filepath/scaling_min_freq
+}
+
+hotplug_with_updates()
+{
+	for_each_non_boot_cpu hotplug_with_updates_cpu
+}