tpm: Factor out common startup code

The TCG standard startup sequence (get timeouts, tpm startup, etc) for
TPM and TPM2 chips is being open coded in many drivers, move it into
the core code.

tpm_tis and tpm_crb are used as the basis for the core code
implementation and the easy drivers are converted. In the process
several small drivers bugs relating to error handling this flow
are fixed.

For now the flag TPM_OPS_AUTO_STARTUP is optional to allow a staged
driver roll out, but ultimately all drivers should use this flow and
the flag removed. Some drivers still do not implement the startup
sequence at all and will need to be tested with it enabled.
Signed-off-by: NJason Gunthorpe <jgunthorpe@obsidianresearch.com>
Tested-by: NAndrew Zamansky <andrew.zamansky@nuvoton.com>
Reviewed-by: NJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: NJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

drivers/char/tpm/st33zp24/st33zp24.c

@@ -505,6 +505,7 @@ static bool st33zp24_req_canceled(struct tpm_chip *chip, u8 status)
 }
 
 static const struct tpm_class_ops st33zp24_tpm = {
+	.flags = TPM_OPS_AUTO_STARTUP,
 	.send = st33zp24_send,
 	.recv = st33zp24_recv,
 	.cancel = st33zp24_cancel,
@@ -592,9 +593,6 @@ int st33zp24_probe(void *phy_id, const struct st33zp24_phy_ops *ops,
 		tpm_gen_interrupt(chip);
 	}
 
-	tpm_get_timeouts(chip);
-	tpm_do_selftest(chip);
-
 	return tpm_chip_register(chip);
 _tpm_clean_answer:
 	dev_info(&chip->dev, "TPM initialization fail\n");

drivers/char/tpm/tpm-chip.c

@@ -354,6 +354,15 @@ int tpm_chip_register(struct tpm_chip *chip)
 {
 	int rc;
 
+	if (chip->ops->flags & TPM_OPS_AUTO_STARTUP) {
+		if (chip->flags & TPM_CHIP_FLAG_TPM2)
+			rc = tpm2_auto_startup(chip);
+		else
+			rc = tpm1_auto_startup(chip);
+		if (rc)
+			return rc;
+	}
+
 	rc = tpm1_chip_register(chip);
 	if (rc)
 		return rc;

drivers/char/tpm/tpm-interface.c

@@ -843,6 +843,33 @@ int tpm_do_selftest(struct tpm_chip *chip)
 }
 EXPORT_SYMBOL_GPL(tpm_do_selftest);
 
+/**
+ * tpm1_auto_startup - Perform the standard automatic TPM initialization
+ *                     sequence
+ * @chip: TPM chip to use
+ *
+ * Returns 0 on success, < 0 in case of fatal error.
+ */
+int tpm1_auto_startup(struct tpm_chip *chip)
+{
+	int rc;
+
+	rc = tpm_get_timeouts(chip);
+	if (rc)
+		goto out;
+	rc = tpm_do_selftest(chip);
+	if (rc) {
+		dev_err(&chip->dev, "TPM self test failed\n");
+		goto out;
+	}
+
+	return rc;
+out:
+	if (rc > 0)
+		rc = -ENODEV;
+	return rc;
+}
+
 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
 {
 	struct tpm_chip *chip;

drivers/char/tpm/tpm.h

@@ -484,6 +484,7 @@ ssize_t tpm_transmit_cmd(struct tpm_chip *chip, void *cmd, int len,
 			 const char *desc);
 extern int tpm_get_timeouts(struct tpm_chip *);
 extern void tpm_gen_interrupt(struct tpm_chip *);
+int tpm1_auto_startup(struct tpm_chip *chip);
 extern int tpm_do_selftest(struct tpm_chip *);
 extern unsigned long tpm_calc_ordinal_duration(struct tpm_chip *, u32);
 extern int tpm_pm_suspend(struct device *);
@@ -526,10 +527,9 @@ int tpm2_unseal_trusted(struct tpm_chip *chip,
 ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,
 			u32 *value, const char *desc);
 
-extern int tpm2_startup(struct tpm_chip *chip, u16 startup_type);
+int tpm2_auto_startup(struct tpm_chip *chip);
 extern void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type);
 extern unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *, u32);
-extern int tpm2_do_selftest(struct tpm_chip *chip);
 extern int tpm2_gen_interrupt(struct tpm_chip *chip);
 extern int tpm2_probe(struct tpm_chip *chip);
 #endif

drivers/char/tpm/tpm2-cmd.c

@@ -728,7 +728,7 @@ static const struct tpm_input_header tpm2_startup_header = {
  * returned it remarks a POSIX error code. If a positive number is returned
  * it remarks a TPM error.
  */
-int tpm2_startup(struct tpm_chip *chip, u16 startup_type)
+static int tpm2_startup(struct tpm_chip *chip, u16 startup_type)
 {
 	struct tpm2_cmd cmd;
 
@@ -738,7 +738,6 @@ int tpm2_startup(struct tpm_chip *chip, u16 startup_type)
 	return tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
 				"attempting to start the TPM");
 }
-EXPORT_SYMBOL_GPL(tpm2_startup);
 
 #define TPM2_SHUTDOWN_IN_SIZE \
 	(sizeof(struct tpm_input_header) + \
@@ -854,7 +853,7 @@ static int tpm2_start_selftest(struct tpm_chip *chip, bool full)
  * returned it remarks a POSIX error code. If a positive number is returned
  * it remarks a TPM error.
  */
-int tpm2_do_selftest(struct tpm_chip *chip)
+static int tpm2_do_selftest(struct tpm_chip *chip)
 {
 	int rc;
 	unsigned int loops;
@@ -894,7 +893,6 @@ int tpm2_do_selftest(struct tpm_chip *chip)
 
 	return rc;
 }
-EXPORT_SYMBOL_GPL(tpm2_do_selftest);
 
 /**
  * tpm2_gen_interrupt() - generate an interrupt
@@ -942,3 +940,43 @@ int tpm2_probe(struct tpm_chip *chip)
 	return 0;
 }
 EXPORT_SYMBOL_GPL(tpm2_probe);
+
+/**
+ * tpm2_auto_startup - Perform the standard automatic TPM initialization
+ *                     sequence
+ * @chip: TPM chip to use
+ *
+ * Returns 0 on success, < 0 in case of fatal error.
+ */
+int tpm2_auto_startup(struct tpm_chip *chip)
+{
+	int rc;
+
+	rc = tpm_get_timeouts(chip);
+	if (rc)
+		goto out;
+
+	rc = tpm2_do_selftest(chip);
+	if (rc != TPM2_RC_INITIALIZE) {
+		dev_err(&chip->dev, "TPM self test failed\n");
+		goto out;
+	}
+
+	if (rc == TPM2_RC_INITIALIZE) {
+		rc = tpm2_startup(chip, TPM2_SU_CLEAR);
+		if (rc)
+			goto out;
+
+		rc = tpm2_do_selftest(chip);
+		if (rc) {
+			dev_err(&chip->dev, "TPM self test failed\n");
+			goto out;
+		}
+	}
+
+	return rc;
+out:
+	if (rc > 0)
+		rc = -ENODEV;
+	return rc;
+}

drivers/char/tpm/tpm_crb.c

@@ -188,6 +188,7 @@ static bool crb_req_canceled(struct tpm_chip *chip, u8 status)
 }
 
 static const struct tpm_class_ops tpm_crb = {
+	.flags = TPM_OPS_AUTO_STARTUP,
 	.status = crb_status,
 	.recv = crb_recv,
 	.send = crb_send,
@@ -200,7 +201,6 @@ static const struct tpm_class_ops tpm_crb = {
 static int crb_init(struct acpi_device *device, struct crb_priv *priv)
 {
 	struct tpm_chip *chip;
-	int rc;
 
 	chip = tpmm_chip_alloc(&device->dev, &tpm_crb);
 	if (IS_ERR(chip))
@@ -210,14 +210,6 @@ static int crb_init(struct acpi_device *device, struct crb_priv *priv)
 	chip->acpi_dev_handle = device->handle;
 	chip->flags = TPM_CHIP_FLAG_TPM2;
 
-	rc = tpm_get_timeouts(chip);
-	if (rc)
-		return rc;
-
-	rc = tpm2_do_selftest(chip);
-	if (rc)
-		return rc;
-
 	return tpm_chip_register(chip);
 }
 

drivers/char/tpm/tpm_i2c_atmel.c

@@ -141,6 +141,7 @@ static bool i2c_atmel_req_canceled(struct tpm_chip *chip, u8 status)
 }
 
 static const struct tpm_class_ops i2c_atmel = {
+	.flags = TPM_OPS_AUTO_STARTUP,
 	.status = i2c_atmel_read_status,
 	.recv = i2c_atmel_recv,
 	.send = i2c_atmel_send,
@@ -179,11 +180,6 @@ static int i2c_atmel_probe(struct i2c_client *client,
 	/* There is no known way to probe for this device, and all version
 	 * information seems to be read via TPM commands. Thus we rely on the
 	 * TPM startup process in the common code to detect the device. */
-	if (tpm_get_timeouts(chip))
-		return -ENODEV;
-
-	if (tpm_do_selftest(chip))
-		return -ENODEV;
 
 	return tpm_chip_register(chip);
 }

drivers/char/tpm/tpm_i2c_infineon.c

@@ -567,6 +567,7 @@ static bool tpm_tis_i2c_req_canceled(struct tpm_chip *chip, u8 status)
 }
 
 static const struct tpm_class_ops tpm_tis_i2c = {
+	.flags = TPM_OPS_AUTO_STARTUP,
 	.status = tpm_tis_i2c_status,
 	.recv = tpm_tis_i2c_recv,
 	.send = tpm_tis_i2c_send,
@@ -619,9 +620,6 @@ static int tpm_tis_i2c_init(struct device *dev)
 
 	tpm_dev.chip = chip;
 
-	tpm_get_timeouts(chip);
-	tpm_do_selftest(chip);
-
 	return tpm_chip_register(chip);
 out_release:
 	release_locality(chip, tpm_dev.locality, 1);

drivers/char/tpm/tpm_i2c_nuvoton.c

@@ -461,6 +461,7 @@ static bool i2c_nuvoton_req_canceled(struct tpm_chip *chip, u8 status)
 }
 
 static const struct tpm_class_ops tpm_i2c = {
+	.flags = TPM_OPS_AUTO_STARTUP,
 	.status = i2c_nuvoton_read_status,
 	.recv = i2c_nuvoton_recv,
 	.send = i2c_nuvoton_send,
@@ -607,12 +608,6 @@ static int i2c_nuvoton_probe(struct i2c_client *client,
 		}
 	}
 
-	if (tpm_get_timeouts(chip))
-		return -ENODEV;
-
-	if (tpm_do_selftest(chip))
-		return -ENODEV;
-
 	return tpm_chip_register(chip);
 }
 

drivers/char/tpm/tpm_tis_core.c

@@ -638,6 +638,7 @@ void tpm_tis_remove(struct tpm_chip *chip)
 EXPORT_SYMBOL_GPL(tpm_tis_remove);
 
 static const struct tpm_class_ops tpm_tis = {
+	.flags = TPM_OPS_AUTO_STARTUP,
 	.status = tpm_tis_status,
 	.recv = tpm_tis_recv,
 	.send = tpm_tis_send,
@@ -773,29 +774,6 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
 		}
 	}
 
-	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
-		rc = tpm2_do_selftest(chip);
-		if (rc == TPM2_RC_INITIALIZE) {
-			dev_warn(dev, "Firmware has not started TPM\n");
-			rc  = tpm2_startup(chip, TPM2_SU_CLEAR);
-			if (!rc)
-				rc = tpm2_do_selftest(chip);
-		}
-
-		if (rc) {
-			dev_err(dev, "TPM self test failed\n");
-			if (rc > 0)
-				rc = -ENODEV;
-			goto out_err;
-		}
-	} else {
-		if (tpm_do_selftest(chip)) {
-			dev_err(dev, "TPM self test failed\n");
-			rc = -ENODEV;
-			goto out_err;
-		}
-	}
-
 	return tpm_chip_register(chip);
 out_err:
 	tpm_tis_remove(chip);

drivers/char/tpm/tpm_vtpm_proxy.c

@@ -346,6 +346,7 @@ static bool vtpm_proxy_tpm_req_canceled(struct tpm_chip  *chip, u8 status)
 }
 
 static const struct tpm_class_ops vtpm_proxy_tpm_ops = {
+	.flags = TPM_OPS_AUTO_STARTUP,
 	.recv = vtpm_proxy_tpm_op_recv,
 	.send = vtpm_proxy_tpm_op_send,
 	.cancel = vtpm_proxy_tpm_op_cancel,
@@ -366,14 +367,6 @@ static void vtpm_proxy_work(struct work_struct *work)
 						   work);
 	int rc;
 
-	if (proxy_dev->flags & VTPM_PROXY_FLAG_TPM2)
-		rc = tpm2_startup(proxy_dev->chip, TPM2_SU_CLEAR);
-	else
-		rc = tpm_get_timeouts(proxy_dev->chip);
-
-	if (rc)
-		goto err;
-
 	rc = tpm_chip_register(proxy_dev->chip);
 	if (rc)
 		goto err;

include/linux/tpm.h

@@ -33,7 +33,12 @@ struct tpm_chip;
 struct trusted_key_payload;
 struct trusted_key_options;
 
+enum TPM_OPS_FLAGS {
+	TPM_OPS_AUTO_STARTUP = BIT(0),
+};
+
 struct tpm_class_ops {
+	unsigned int flags;
 	const u8 req_complete_mask;
 	const u8 req_complete_val;
 	bool (*req_canceled)(struct tpm_chip *chip, u8 status);