[PATCH v8 5/8] tpm: Handle an exception for TPM Firmware Update mode.

amirmizi6
2020-05-12T14:16:12Z

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.

Suggested-by: Benoit Houyere <benoit.houyere@st.com>
Signed-off-by: Amir Mizinski <amirmizi6@gmail.com>
---
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 7603295..6e42946 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -727,6 +727,10 @@ 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