1 files changed, 85 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 100755
index 000000000..00dc32c0e
--- /dev/null
+++ b/tools/testing/selftests/powerpc/eeh/eeh-functions.sh
@@ -0,0 +1,85 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0-only
+
+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_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
+		echo "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 $dev ; then
+			break;
+		fi
+		echo "$dev, waited $i/${max_wait}"
+		sleep 1
+	done
+
+	if ! pe_ok $dev ; then
+		echo "$dev, Failed to recover!"
+		return 1;
+	fi
+
+	echo "$dev, Recovered after $i seconds"
+	return 0;
+}
+