vtpm-command-duration.patch

From e7c976b5864e7d2649292d90ea60d5aea091a990 Mon Sep 17 00:00:00 2001
From: Jason Andryuk <jandryuk@gmail.com>
Date: Sun, 14 Mar 2021 12:46:34 -0400
Subject: [PATCH 2/2] Increase command durations

Wth Linux 5.4 xen-tpmfront and a Xen vtpm-stubdom, xen-tpmfront was
failing commands with -ETIME:
tpm tpm0: tpm_try_transmit: send(): error-62

The vtpm was returning the data, but it was after the duration timeout
in vtpm_send.  Linux may have started being more stringent about timing?

The vtpm-stubdom has a little delay since it writes its disk before
returning the response.

Anyway, the durations are rather low.  When they were 1/10/1000 before
converting to microseconds, Linux showed all three durations rounded to
10000.  Update them with values from a physical TPM1.2.  These were
taken from a WEC which was software downgraded from a TPM2 to a TPM1.2.
They might be excessive, but I'd rather have a command succeed than
return -ETIME.

An IFX physical TPM1.2 uses:
1000000
1500000
150000000

Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
---
 tpm/tpm_data.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tpm/tpm_data.c b/tpm/tpm_data.c
index bebaf10..844afca 100644
--- a/tpm/tpm_data.c
+++ b/tpm/tpm_data.c
@@ -71,9 +71,9 @@ static void init_timeouts(void)
   tpmData.permanent.data.tis_timeouts[1] = 2000000;
   tpmData.permanent.data.tis_timeouts[2] = 750000;
   tpmData.permanent.data.tis_timeouts[3] = 750000;
-  tpmData.permanent.data.cmd_durations[0] = 1000;
-  tpmData.permanent.data.cmd_durations[1] = 10000;
-  tpmData.permanent.data.cmd_durations[2] = 1000000;
+  tpmData.permanent.data.cmd_durations[0] = 3000000;
+  tpmData.permanent.data.cmd_durations[1] = 3000000;
+  tpmData.permanent.data.cmd_durations[2] = 600000000;
 }
 
 void tpm_init_data(void)
-- 
2.30.2