4 files changed, 61 insertions, 0 deletions

diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index aade6995f310..a321bd57f3e9 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -231,6 +231,7 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
 		goto out;
 	}
 
+	chip->locality = -1;
 	return chip;
 
 out:
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 16abbf9cb53a..158c1db83f05 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -389,6 +389,7 @@ ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
 	ssize_t len = 0;
 	u32 count, ordinal;
 	unsigned long stop;
+	bool need_locality;
 
 	if (!tpm_validate_command(chip, space, buf, bufsiz))
 		return -EINVAL;
@@ -412,6 +413,16 @@ ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
 	if (chip->dev.parent)
 		pm_runtime_get_sync(chip->dev.parent);
 
+	/* Store the decision as chip->locality will be changed. */
+	need_locality = chip->locality == -1;
+
+	if (need_locality && chip->ops->request_locality)  {
+		rc = chip->ops->request_locality(chip, 0);
+		if (rc < 0)
+			goto out_no_locality;
+		chip->locality = rc;
+	}
+
 	rc = tpm2_prepare_space(chip, space, ordinal, buf);
 	if (rc)
 		goto out;
@@ -471,6 +482,11 @@ out_recv:
 	rc = tpm2_commit_space(chip, space, ordinal, buf, &len);
 
 out:
+	if (need_locality && chip->ops->relinquish_locality) {
+		chip->ops->relinquish_locality(chip, chip->locality);
+		chip->locality = -1;
+	}
+out_no_locality:
 	if (chip->dev.parent)
 		pm_runtime_put_sync(chip->dev.parent);
 
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 5eacb3fd2ed2..4b4c8dee3096 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -228,6 +228,9 @@ struct tpm_chip {
 	struct tpm_space work_space;
 	u32 nr_commands;
 	u32 *cc_attrs_tbl;
+
+	/* active locality */
+	int locality;
 };
 
 #define to_tpm_chip(d) container_of(d, struct tpm_chip, dev)
diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c
index 9f3160912152..d91e47dc2d79 100644
--- a/drivers/char/tpm/tpm_crb.c
+++ b/drivers/char/tpm/tpm_crb.c
@@ -34,6 +34,16 @@ enum crb_defaults {
 	CRB_ACPI_START_INDEX = 1,
 };
 
+enum crb_loc_ctrl {
+	CRB_LOC_CTRL_REQUEST_ACCESS	= BIT(0),
+	CRB_LOC_CTRL_RELINQUISH		= BIT(1),
+};
+
+enum crb_loc_state {
+	CRB_LOC_STATE_LOC_ASSIGNED	= BIT(1),
+	CRB_LOC_STATE_TPM_REG_VALID_STS	= BIT(7),
+};
+
 enum crb_ctrl_req {
 	CRB_CTRL_REQ_CMD_READY	= BIT(0),
 	CRB_CTRL_REQ_GO_IDLE	= BIT(1),
@@ -172,6 +182,35 @@ static int __maybe_unused crb_cmd_ready(struct device *dev,
 	return 0;
 }
 
+static int crb_request_locality(struct tpm_chip *chip, int loc)
+{
+	struct crb_priv *priv = dev_get_drvdata(&chip->dev);
+	u32 value = CRB_LOC_STATE_LOC_ASSIGNED |
+		CRB_LOC_STATE_TPM_REG_VALID_STS;
+
+	if (!priv->regs_h)
+		return 0;
+
+	iowrite32(CRB_LOC_CTRL_REQUEST_ACCESS, &priv->regs_h->loc_ctrl);
+	if (!crb_wait_for_reg_32(&priv->regs_h->loc_state, value, value,
+				 TPM2_TIMEOUT_C)) {
+		dev_warn(&chip->dev, "TPM_LOC_STATE_x.requestAccess timed out\n");
+		return -ETIME;
+	}
+
+	return 0;
+}
+
+static void crb_relinquish_locality(struct tpm_chip *chip, int loc)
+{
+	struct crb_priv *priv = dev_get_drvdata(&chip->dev);
+
+	if (!priv->regs_h)
+		return;
+
+	iowrite32(CRB_LOC_CTRL_RELINQUISH, &priv->regs_h->loc_ctrl);
+}
+
 static u8 crb_status(struct tpm_chip *chip)
 {
 	struct crb_priv *priv = dev_get_drvdata(&chip->dev);
@@ -278,6 +317,8 @@ static const struct tpm_class_ops tpm_crb = {
 	.send = crb_send,
 	.cancel = crb_cancel,
 	.req_canceled = crb_req_canceled,
+	.request_locality = crb_request_locality,
+	.relinquish_locality = crb_relinquish_locality,
 	.req_complete_mask = CRB_DRV_STS_COMPLETE,
 	.req_complete_val = CRB_DRV_STS_COMPLETE,
 };