selftests/eeh: Bump EEH wait time to 60s

[ Upstream commit 414f50434a ]

Some newer cards supported by aacraid can take up to 40s to recover
after an EEH event. This causes spurious failures in the basic EEH
self-test since the current maximim timeout is only 30s.

Fix the immediate issue by bumping the timeout to a default of 60s,
and allow the wait time to be specified via an environmental variable
(EEH_MAX_WAIT).

Reported-by: Steve Best <sbest@redhat.com>
Suggested-by: Douglas Miller <dougmill@us.ibm.com>
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200122031125.25991-1-oohall@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

tools/testing/selftests/powerpc/eeh/eeh-functions.sh

@@ -53,9 +53,13 @@ eeh_one_dev() {
 	# is a no-op.
 	echo $dev >/sys/kernel/debug/powerpc/eeh_dev_check
 
-	# Enforce a 30s timeout for recovery. Even the IPR, which is infamously
-	# slow to reset, should recover within 30s.
-	max_wait=30
+	# 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