tpm_tis: use default timeout value if chip reports it as zero

maciejsszmigiero · Jarkko Sakkinen · commit 1d70fe9d9c3a · 2017-01-23T18:28:18.000+02:00
Since commit 1107d06 ("tpm_tis: Introduce intermediate layer for TPM access") Atmel 3203 TPM on ThinkPad X61S (TPM firmware version 13.9) no longer works. The initialization proceeds fine until we get and start using chip-reported timeouts - and the chip reports C and D timeouts of zero. It turns out that until commit 8e54caf ("tpm: Provide a generic means to override the chip returned timeouts") we had actually let default timeout values remain in this case, so let's bring back this behavior to make chips like Atmel 3203 work again. Use a common code that was introduced by that commit so a warning is printed in this case and /sys/class/tpm/tpm*/timeouts correctly says the timeouts aren't chip-original. Fixes: 1107d06 ("tpm_tis: Introduce intermediate layer for TPM access") Cc: stable@vger.kernel.org Signed-off-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
@@ -522,8 +522,7 @@ static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
 int tpm_get_timeouts(struct tpm_chip *chip)
 {
 	cap_t cap;
-	unsigned long new_timeout[4];
-	unsigned long old_timeout[4];
+	unsigned long timeout_old[4], timeout_chip[4], timeout_eff[4];
 	ssize_t rc;
 
 	if (chip->flags & TPM_CHIP_FLAG_HAVE_TIMEOUTS)
@@ -564,28 +563,40 @@ int tpm_get_timeouts(struct tpm_chip *chip)
 		return rc;
 	}
 
-	old_timeout[0] = be32_to_cpu(cap.timeout.a);
-	old_timeout[1] = be32_to_cpu(cap.timeout.b);
-	old_timeout[2] = be32_to_cpu(cap.timeout.c);
-	old_timeout[3] = be32_to_cpu(cap.timeout.d);
-	memcpy(new_timeout, old_timeout, sizeof(new_timeout));
+	timeout_old[0] = jiffies_to_usecs(chip->timeout_a);
+	timeout_old[1] = jiffies_to_usecs(chip->timeout_b);
+	timeout_old[2] = jiffies_to_usecs(chip->timeout_c);
+	timeout_old[3] = jiffies_to_usecs(chip->timeout_d);
+	timeout_chip[0] = be32_to_cpu(cap.timeout.a);
+	timeout_chip[1] = be32_to_cpu(cap.timeout.b);
+	timeout_chip[2] = be32_to_cpu(cap.timeout.c);
+	timeout_chip[3] = be32_to_cpu(cap.timeout.d);
+	memcpy(timeout_eff, timeout_chip, sizeof(timeout_eff));
 
 	/*
 	 * Provide ability for vendor overrides of timeout values in case
 	 * of misreporting.
 	 */
 	if (chip->ops->update_timeouts != NULL)
 		chip->timeout_adjusted =
-			chip->ops->update_timeouts(chip, new_timeout);
+			chip->ops->update_timeouts(chip, timeout_eff);
 
 	if (!chip->timeout_adjusted) {
-		/* Don't overwrite default if value is 0 */
-		if (new_timeout[0] != 0 && new_timeout[0] < 1000) {
-			int i;
+		/* Restore default if chip reported 0 */
+		int i;
 
+		for (i = 0; i < ARRAY_SIZE(timeout_eff); i++) {
+			if (timeout_eff[i])
+				continue;
+
+			timeout_eff[i] = timeout_old[i];
+			chip->timeout_adjusted = true;
+		}
+
+		if (timeout_eff[0] != 0 && timeout_eff[0] < 1000) {
 			/* timeouts in msec rather usec */
-			for (i = 0; i != ARRAY_SIZE(new_timeout); i++)
-				new_timeout[i] *= 1000;
+			for (i = 0; i != ARRAY_SIZE(timeout_eff); i++)
+				timeout_eff[i] *= 1000;
 			chip->timeout_adjusted = true;
 		}
 	}
@@ -594,16 +605,16 @@ int tpm_get_timeouts(struct tpm_chip *chip)
 	if (chip->timeout_adjusted) {
 		dev_info(&chip->dev,
 			 HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n",
-			 old_timeout[0], new_timeout[0],
-			 old_timeout[1], new_timeout[1],
-			 old_timeout[2], new_timeout[2],
-			 old_timeout[3], new_timeout[3]);
+			 timeout_chip[0], timeout_eff[0],
+			 timeout_chip[1], timeout_eff[1],
+			 timeout_chip[2], timeout_eff[2],
+			 timeout_chip[3], timeout_eff[3]);
 	}
 
-	chip->timeout_a = usecs_to_jiffies(new_timeout[0]);
-	chip->timeout_b = usecs_to_jiffies(new_timeout[1]);
-	chip->timeout_c = usecs_to_jiffies(new_timeout[2]);
-	chip->timeout_d = usecs_to_jiffies(new_timeout[3]);
+	chip->timeout_a = usecs_to_jiffies(timeout_eff[0]);
+	chip->timeout_b = usecs_to_jiffies(timeout_eff[1]);
+	chip->timeout_c = usecs_to_jiffies(timeout_eff[2]);
+	chip->timeout_d = usecs_to_jiffies(timeout_eff[3]);
 
 	rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap,
 			"attempting to determine the durations");
diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c
@@ -159,7 +159,7 @@ static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info,
 		irq = tpm_info->irq;
 
 	if (itpm)
-		phy->priv.flags |= TPM_TIS_ITPM_POSSIBLE;
+		phy->priv.flags |= TPM_TIS_ITPM_WORKAROUND;
 
 	return tpm_tis_core_init(dev, &phy->priv, irq, &tpm_tcg,
 				 acpi_dev_handle);
diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
@@ -264,7 +264,7 @@ static int tpm_tis_send_data(struct tpm_chip *chip, u8 *buf, size_t len)
 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 	int rc, status, burstcnt;
 	size_t count = 0;
-	bool itpm = priv->flags & TPM_TIS_ITPM_POSSIBLE;
+	bool itpm = priv->flags & TPM_TIS_ITPM_WORKAROUND;
 
 	if (request_locality(chip, 0) < 0)
 		return -EBUSY;
@@ -740,15 +740,15 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
 		 (chip->flags & TPM_CHIP_FLAG_TPM2) ? "2.0" : "1.2",
 		 vendor >> 16, rid);
 
-	if (!(priv->flags & TPM_TIS_ITPM_POSSIBLE)) {
+	if (!(priv->flags & TPM_TIS_ITPM_WORKAROUND)) {
 		probe = probe_itpm(chip);
 		if (probe < 0) {
 			rc = -ENODEV;
 			goto out_err;
 		}
 
 		if (!!probe)
-			priv->flags |= TPM_TIS_ITPM_POSSIBLE;
+			priv->flags |= TPM_TIS_ITPM_WORKAROUND;
 	}
 
 	/* Figure out the capabilities */
diff --git a/drivers/char/tpm/tpm_tis_core.h b/drivers/char/tpm/tpm_tis_core.h
@@ -80,7 +80,7 @@ enum tis_defaults {
 #define	TPM_RID(l)			(0x0F04 | ((l) << 12))
 
 enum tpm_tis_flags {
-	TPM_TIS_ITPM_POSSIBLE		= BIT(0),
+	TPM_TIS_ITPM_WORKAROUND		= BIT(0),
 };
 
 struct tpm_tis_data {
