On 10/2/24 1:04 PM, Jonathan McDowell wrote:
(I'm still in the process of testing this to confirm it fixes the
errata I've seen, but I wanted to send it out for comments to make sure
it's a reasonable approach.)
Some Infineon devices have a issue where the status register will get
stuck with a quick REQUEST_USE / COMMAND_READY sequence. The work around
Did you tell Infineon about it? Maybe they should have a look at their
firmware.
What are the TPMs in your fleet doing? I heared that some TPMs
pre-create keys in the background once users requested a few. I would
try to create a few primary keys with different combination of key flags
set and in different hierarchies (and flush them) to use up these
precreated keys and see whether that leads to any issues with the TIS
responsiveness once presumably the device starts creating keys in the
background...
is to retry the command submission. Add appropriate logic to do this in
I would describe it as 'retrying to set the TPM_STS_COMMAND_READY flag
on the TIS STS register' because you are not retring a (TPM) command
submission, like resubmitting a TPM2_PCR_Extend for example.
the send path.
Signed-off-by: Jonathan McDowell <noodles@xxxxxxxx>
---
drivers/char/tpm/tpm_tis_core.c | 24 +++++++++++++++++++-----
drivers/char/tpm/tpm_tis_core.h | 1 +
include/linux/tpm.h | 1 +
3 files changed, 21 insertions(+), 5 deletions(-)
diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index f6aa0dfadb93..940abd1a868e 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -432,16 +432,27 @@ static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count)
static int tpm_tis_send_data(struct tpm_chip *chip, const u8 *buf, size_t len)
{
struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
- int rc, status, burstcnt;
+ int rc, status, burstcnt, retry;
+ bool status_fix = test_bit(TPM_TIS_STATUS_WORKAROUND, &priv->flags);
This should probably be moved to the top.
int retry = status_fix ? 3 : 1;
size_t count = 0;
bool itpm = test_bit(TPM_TIS_ITPM_WORKAROUND, &priv->flags);
status = tpm_tis_status(chip);
if ((status & TPM_STS_COMMAND_READY) == 0) {
- tpm_tis_ready(chip);
- if (wait_for_tpm_stat
- (chip, TPM_STS_COMMAND_READY, chip->timeout_b,
- &priv->int_queue, false) < 0) {
+ retry = status_fix ? 3 : 1;
+
+ while (retry > 0) {
+ tpm_tis_ready(chip);
+ if (wait_for_tpm_stat
+ (chip, TPM_STS_COMMAND_READY, chip->timeout_b,
+ &priv->int_queue, false) >= 0) {
+ break;
+ }
+
+ retry--;
+ }
+
+ if (retry == 0) {
rc = -ETIME;
goto out_err;
}
@@ -1147,6 +1158,9 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
priv->timeout_max = TIS_TIMEOUT_MAX_ATML;
}
+ if (priv->manufacturer_id == TPM_VID_IFX)
+ set_bit(TPM_TIS_STATUS_WORKAROUND, &priv->flags);
+
if (is_bsw()) {
priv->ilb_base_addr = ioremap(INTEL_LEGACY_BLK_BASE_ADDR,
ILB_REMAP_SIZE);
diff --git a/drivers/char/tpm/tpm_tis_core.h b/drivers/char/tpm/tpm_tis_core.h
index 13e99cf65efe..f888da57535d 100644
--- a/drivers/char/tpm/tpm_tis_core.h
+++ b/drivers/char/tpm/tpm_tis_core.h
@@ -89,6 +89,7 @@ enum tpm_tis_flags {
TPM_TIS_INVALID_STATUS = 1,
TPM_TIS_DEFAULT_CANCELLATION = 2,
TPM_TIS_IRQ_TESTED = 3,
+ TPM_TIS_STATUS_WORKAROUND = 4,
};
struct tpm_tis_data {
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 4ee9d13749ad..5f4998626a98 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -272,6 +272,7 @@ enum tpm2_cc_attrs {
#define TPM_VID_WINBOND 0x1050
#define TPM_VID_STM 0x104A
#define TPM_VID_ATML 0x1114
+#define TPM_VID_IFX 0x15D1
enum tpm_chip_flags {
TPM_CHIP_FLAG_BOOTSTRAPPED = BIT(0),
