diff options
| -rw-r--r-- | libstb/drivers/tpm_i2c_nuvoton.c | 82 |
1 files changed, 50 insertions, 32 deletions
diff --git a/libstb/drivers/tpm_i2c_nuvoton.c b/libstb/drivers/tpm_i2c_nuvoton.c index 7413770..05a90fc 100644 --- a/libstb/drivers/tpm_i2c_nuvoton.c +++ b/libstb/drivers/tpm_i2c_nuvoton.c @@ -101,48 +101,70 @@ static int tpm_read_sts_reg_valid(uint8_t* value) return STB_TPM_TIMEOUT; } -static bool tpm_is_command_ready(int* rc) +static int tpm_wait_for_command_ready(void) { - uint8_t value = 0; - *rc = tpm_status_read_byte(TPM_STS, &value); - if (*rc < 0) - false; - if (tpm_check_status(value, TPM_STS_COMMAND_READY, - TPM_STS_COMMAND_READY)) { - DBG("---- TPM is command ready\n"); - return true; + int rc, delay; + uint8_t status; + + for (delay = 0; delay < TPM_TIMEOUT_B; + delay += TPM_TIMEOUT_INTERVAL) { + rc = tpm_status_read_byte(TPM_STS, &status); + if (rc < 0) { + /** + * @fwts-label TPMReadCmdReady + * @fwts-advice Either the tpm device or the tpm-i2c + * interface doesn't seem to be working properly. Check + * the return code (rc) for further details. + */ + prlog(PR_ERR, "NUVOTON: fail to read sts.commandReady, " + "rc=%d\n", rc); + return STB_DRIVER_ERROR; + } + if (tpm_check_status(status, + TPM_STS_COMMAND_READY, + TPM_STS_COMMAND_READY)) { + DBG("--- Command ready, delay=%d/%d\n", + delay, TPM_TIMEOUT_B); + return 0; + } + time_wait_ms(TPM_TIMEOUT_INTERVAL); } - return false; + return STB_TPM_TIMEOUT; } -static int tpm_poll_for_command_ready(void) +static int tpm_set_command_ready(void) { - int rc, polls, delay; + int rc, retries; /* * The first write to command ready may just abort an * outstanding command, so we poll twice */ - for (polls=0; polls<2; polls++) { + for (retries = 0; retries < 2; retries++) { rc = tpm_status_write_byte(TPM_STS_COMMAND_READY); if (rc < 0) { - return rc; - } - for (delay = 0; delay < TPM_TIMEOUT_B; - delay += TPM_TIMEOUT_INTERVAL) { - if (tpm_is_command_ready(&rc)) - return rc; - time_wait_ms(TPM_TIMEOUT_INTERVAL); + /** + * @fwts-label TPMWriteCmdReady + * @fwts-advice Either the tpm device or the tpm-i2c + * interface doesn't seem to be working properly. Check + * the return code (rc) for further details. + */ + prlog(PR_ERR, "NUVOTON: fail to write sts.commandReady, " + "rc=%d\n", rc); + return STB_DRIVER_ERROR; } - DBG("--- Command ready polling, delay %d/%d\n", - delay, TPM_TIMEOUT_B); + rc = tpm_wait_for_command_ready(); + if (rc == STB_TPM_TIMEOUT) + continue; + return rc; } /** - * @fwts-label TPMCommandReadyBitTimeout + * @fwts-label TPMCmdReadyTimeout * @fwts-advice The command ready bit of the tpm status register is * taking longer to be settled. Either the wait time need to be * increased or the TPM device is not functional. */ - prlog(PR_ERR, "TPM: command ready polling timeout\n"); + prlog(PR_ERR, "NUVOTON: timeout on sts.commandReady, delay > %d\n", + 2*TPM_TIMEOUT_B); return STB_TPM_TIMEOUT; } @@ -415,14 +437,10 @@ static int tpm_transmit(struct tpm_dev *dev, uint8_t* buf, size_t cmdlen, __func__, dev->bus_id, dev->xscom_base, *(uint64_t*) buf, cmdlen, *buflen); - DBG("step 1/5: check command ready\n"); - if (!tpm_is_command_ready(&rc)) { - if (rc < 0) - goto out; - rc = tpm_poll_for_command_ready(); - if (rc < 0) - goto out; - } + DBG("step 1/5: set command ready\n"); + rc = tpm_set_command_ready(); + if (rc < 0) + goto out; DBG("step 2/5: write FIFO\n"); rc = tpm_write_fifo(buf, cmdlen); |