1 files changed, 245 insertions, 0 deletions
diff --git a/tools/testing/selftests/powerpc/eeh/eeh-functions.sh b/tools/testing/selftests/powerpc/eeh/eeh-functions.sh
new file mode 100644
index 000000000..70daa3925
--- /dev/null
+++ b/tools/testing/selftests/powerpc/eeh/eeh-functions.sh
@@ -0,0 +1,245 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0-only
+
+export KSELFTESTS_SKIP=4
+
+log() {
+	echo >/dev/stderr $*
+}
+
+pe_ok() {
+	local dev="$1"
+	local path="/sys/bus/pci/devices/$dev/eeh_pe_state"
+
+	# if a driver doesn't support the error handling callbacks then the
+	# device is recovered by removing and re-probing it. This causes the
+	# sysfs directory to disappear so read the PE state once and squash
+	# any potential error messages
+	local eeh_state="$(cat $path 2>/dev/null)"
+	if [ -z "$eeh_state" ]; then
+		return 1;
+	fi
+
+	local fw_state="$(echo $eeh_state | cut -d' ' -f1)"
+	local sw_state="$(echo $eeh_state | cut -d' ' -f2)"
+
+	# If EEH_PE_ISOLATED or EEH_PE_RECOVERING are set then the PE is in an
+	# error state or being recovered. Either way, not ok.
+	if [ "$((sw_state & 0x3))" -ne 0 ] ; then
+		return 1
+	fi
+
+	# A functioning PE should have the EEH_STATE_MMIO_ACTIVE and
+	# EEH_STATE_DMA_ACTIVE flags set. For some goddamn stupid reason
+	# the platform backends set these when the PE is in reset. The
+	# RECOVERING check above should stop any false positives though.
+	if [ "$((fw_state & 0x18))" -ne "$((0x18))" ] ; then
+		return 1
+	fi
+
+	return 0;
+}
+
+eeh_supported() {
+	test -e /proc/powerpc/eeh && \
+	grep -q 'EEH Subsystem is enabled' /proc/powerpc/eeh
+}
+
+eeh_test_prep() {
+	if ! eeh_supported ; then
+		echo "EEH not supported on this system, skipping"
+		exit $KSELFTESTS_SKIP;
+	fi
+
+	if [ ! -e "/sys/kernel/debug/powerpc/eeh_dev_check" ] && \
+	   [ ! -e "/sys/kernel/debug/powerpc/eeh_dev_break" ] ; then
+		log "debugfs EEH testing files are missing. Is debugfs mounted?"
+		exit $KSELFTESTS_SKIP;
+	fi
+
+	# Bump the max freeze count to something absurd so we don't
+	# trip over it while breaking things.
+	echo 5000 > /sys/kernel/debug/powerpc/eeh_max_freezes
+}
+
+eeh_can_break() {
+	# skip bridges since we can't recover them (yet...)
+	if [ -e "/sys/bus/pci/devices/$dev/pci_bus" ] ; then
+		log "$dev, Skipped: bridge"
+		return 1;
+	fi
+
+	# The ahci driver doesn't support error recovery. If the ahci device
+	# happens to be hosting the root filesystem, and then we go and break
+	# it the system will generally go down. We should probably fix that
+	# at some point
+	if [ "ahci" = "$(basename $(realpath /sys/bus/pci/devices/$dev/driver))" ] ; then
+		log "$dev, Skipped: ahci doesn't support recovery"
+		return 1;
+	fi
+
+	# Don't inject errosr into an already-frozen PE. This happens with
+	# PEs that contain multiple PCI devices (e.g. multi-function cards)
+	# and injecting new errors during the recovery process will probably
+	# result in the recovery failing and the device being marked as
+	# failed.
+	if ! pe_ok $dev ; then
+		log "$dev, Skipped: Bad initial PE state"
+		return 1;
+	fi
+
+	return 0
+}
+
+eeh_one_dev() {
+	local dev="$1"
+
+	# Using this function from the command line is sometimes useful for
+	# testing so check that the argument is a well-formed sysfs device
+	# name.
+	if ! test -e /sys/bus/pci/devices/$dev/ ; then
+		log "Error: '$dev' must be a sysfs device name (DDDD:BB:DD.F)"
+		return 1;
+	fi
+
+	# Break it
+	echo $dev >/sys/kernel/debug/powerpc/eeh_dev_break
+
+	# Force an EEH device check. If the kernel has already
+	# noticed the EEH (due to a driver poll or whatever), this
+	# is a no-op.
+	echo $dev >/sys/kernel/debug/powerpc/eeh_dev_check
+
+	# Default to a 60s timeout when waiting for a device to recover. This
+	# is an arbitrary default which can be overridden by setting the
+	# EEH_MAX_WAIT environmental variable when required.
+
+	# The current record holder for longest recovery time is:
+	#  "Adaptec Series 8 12G SAS/PCIe 3" at 39 seconds
+	max_wait=${EEH_MAX_WAIT:=60}
+
+	for i in `seq 0 ${max_wait}` ; do
+		if pe_ok $dev ; then
+			break;
+		fi
+		log "$dev, waited $i/${max_wait}"
+		sleep 1
+	done
+
+	if ! pe_ok $dev ; then
+		log "$dev, Failed to recover!"
+		return 1;
+	fi
+
+	log "$dev, Recovered after $i seconds"
+	return 0;
+}
+
+eeh_has_driver() {
+	test -e /sys/bus/pci/devices/$1/driver;
+	return $?
+}
+
+eeh_can_recover() {
+	# we'll get an IO error if the device's current driver doesn't support
+	# error recovery
+	echo $1 > '/sys/kernel/debug/powerpc/eeh_dev_can_recover' 2>/dev/null
+
+	return $?
+}
+
+eeh_find_all_pfs() {
+	devices=""
+
+	# SR-IOV on pseries requires hypervisor support, so check for that
+	is_pseries=""
+	if grep -q pSeries /proc/cpuinfo ; then
+		if [ ! -f /proc/device-tree/rtas/ibm,open-sriov-allow-unfreeze ] ||
+		   [ ! -f /proc/device-tree/rtas/ibm,open-sriov-map-pe-number ] ; then
+			return 1;
+		fi
+
+		is_pseries="true"
+	fi
+
+	for dev in `ls -1 /sys/bus/pci/devices/` ; do
+		sysfs="/sys/bus/pci/devices/$dev"
+		if [ ! -e "$sysfs/sriov_numvfs" ] ; then
+			continue
+		fi
+
+		# skip unsupported PFs on pseries
+		if [ -z "$is_pseries" ] &&
+		   [ ! -f "$sysfs/of_node/ibm,is-open-sriov-pf" ] &&
+		   [ ! -f "$sysfs/of_node/ibm,open-sriov-vf-bar-info" ] ; then
+			continue;
+		fi
+
+		# no driver, no vfs
+		if ! eeh_has_driver $dev ; then
+			continue
+		fi
+
+		devices="$devices $dev"
+	done
+
+	if [ -z "$devices" ] ; then
+		return 1;
+	fi
+
+	echo $devices
+	return 0;
+}
+
+# attempts to enable one VF on each PF so we can do VF specific tests.
+# stdout: list of enabled VFs, one per line
+# return code: 0 if vfs are found, 1 otherwise
+eeh_enable_vfs() {
+	pf_list="$(eeh_find_all_pfs)"
+
+	vfs=0
+	for dev in $pf_list ; do
+		pf_sysfs="/sys/bus/pci/devices/$dev"
+
+		# make sure we have a single VF
+		echo 0 > "$pf_sysfs/sriov_numvfs"
+		echo 1 > "$pf_sysfs/sriov_numvfs"
+		if [ "$?" != 0 ] ; then
+			log "Unable to enable VFs on $pf, skipping"
+			continue;
+		fi
+
+		vf="$(basename $(realpath "$pf_sysfs/virtfn0"))"
+		if [ $? != 0 ] ; then
+			log "unable to find enabled vf on $pf"
+			echo 0 > "$pf_sysfs/sriov_numvfs"
+			continue;
+		fi
+
+		if ! eeh_can_break $vf ; then
+			log "skipping "
+
+			echo 0 > "$pf_sysfs/sriov_numvfs"
+			continue;
+		fi
+
+		vfs="$((vfs + 1))"
+		echo $vf
+	done
+
+	test "$vfs" != 0
+	return $?
+}
+
+eeh_disable_vfs() {
+	pf_list="$(eeh_find_all_pfs)"
+	if [ -z "$pf_list" ] ; then
+		return 1;
+	fi
+
+	for dev in $pf_list ; do
+		echo 0 > "/sys/bus/pci/devices/$dev/sriov_numvfs"
+	done
+
+	return 0;
+}