(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 is to retry the command submission. Add appropriate logic to do this in the send path. Signed-off-by: Jonathan McDowell <[email protected]> --- 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); 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), -- 2.39.5
