[PATCH v3 5/7] tpm: Handle an exception for TPM Firmware Update mode.

From: amirmizi6
Date: Mon Feb 10 2020 - 12:10:00 EST


From: Amir Mizinski <amirmizi6@xxxxxxxxx>

An extra precaution for TPM Firmware Update Mode.
For example if TPM power was cut while in Firmware update, platform
should ignore selftest failure and skip TPM initialization sequence.

This improvment was suggested by Benoit Houyere.

Signed-off-by: Amir Mizinski <amirmizi6@xxxxxxxxx>
---
drivers/char/tpm/tpm2-cmd.c | 4 ++++
include/linux/tpm.h | 1 +
2 files changed, 5 insertions(+)

diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 13696de..997b11e 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -725,6 +725,10 @@ int tpm2_auto_startup(struct tpm_chip *chip)
goto out;

rc = tpm2_do_selftest(chip);
+
+ if ((rc == TPM2_RC_UPGRADE) || (rc == TPM2_RC_COMMAND_CODE))
+ return 0;
+
if (rc && rc != TPM2_RC_INITIALIZE)
goto out;

diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 03e9b18..5a2e031 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -199,6 +199,7 @@ enum tpm2_return_codes {
TPM2_RC_INITIALIZE = 0x0100, /* RC_VER1 */
TPM2_RC_FAILURE = 0x0101,
TPM2_RC_DISABLED = 0x0120,
+ TPM2_RC_UPGRADE = 0x012D,
TPM2_RC_COMMAND_CODE = 0x0143,
TPM2_RC_TESTING = 0x090A, /* RC_WARN */
TPM2_RC_REFERENCE_H0 = 0x0910,
--
2.7.4