The correct sequence is to first request locality and only after
that perform cmd_ready handshake, otherwise the hardware will drop
the subsequent message as from the device point of view the cmd_ready
handshake wasn't performed. Symmetrically locality has to be relinquished
only after going idle handshake has completed, this requires that
go_idle has to poll for the completion.
The issue is only visible on devices that support multiple localities.
Signed-off-by: Tomas Winkler <tomas.winkler@xxxxxxxxx>
---
drivers/char/tpm/tpm-interface.c | 12 ++---
drivers/char/tpm/tpm_crb.c | 95 ++++++++++++++++++++++++++--------------
2 files changed, 70 insertions(+), 37 deletions(-)
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 76df4fbcf089..197fda39aab5 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -422,8 +422,6 @@ ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
if (!(flags & TPM_TRANSMIT_UNLOCKED))
mutex_lock(&chip->tpm_mutex);
- if (chip->dev.parent)
- pm_runtime_get_sync(chip->dev.parent);
if (chip->ops->clk_enable != NULL)
chip->ops->clk_enable(chip, true);
@@ -439,6 +437,9 @@ ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
chip->locality = rc;
}
+ if (chip->dev.parent)
+ pm_runtime_get_sync(chip->dev.parent);
+
rc = tpm2_prepare_space(chip, space, ordinal, buf);
if (rc)
goto out;
@@ -499,17 +500,18 @@ ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
rc = tpm2_commit_space(chip, space, ordinal, buf, &len);
out:
+ if (chip->dev.parent)
+ pm_runtime_put_sync(chip->dev.parent);
+
if (need_locality && chip->ops->relinquish_locality) {
chip->ops->relinquish_locality(chip, chip->locality);
chip->locality = -1;
}
+
out_no_locality:
if (chip->ops->clk_enable != NULL)
chip->ops->clk_enable(chip, false);
- if (chip->dev.parent)
- pm_runtime_put_sync(chip->dev.parent);
-
if (!(flags & TPM_TRANSMIT_UNLOCKED))
mutex_unlock(&chip->tpm_mutex);
return rc ? rc : len;
diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c
index 7b3c2a8aa9de..d174919c446d 100644
--- a/drivers/char/tpm/tpm_crb.c
+++ b/drivers/char/tpm/tpm_crb.c
@@ -112,6 +112,25 @@ struct tpm2_crb_smc {
u32 smc_func_id;
};
+static bool crb_wait_for_reg_32(u32 __iomem *reg, u32 mask, u32 value,
+ unsigned long timeout)
+{
+ ktime_t start;
+ ktime_t stop;
+
+ start = ktime_get();
+ stop = ktime_add(start, ms_to_ktime(timeout));
+
+ do {
+ if ((ioread32(reg) & mask) == value)
+ return true;
+
+ usleep_range(50, 100);
+ } while (ktime_before(ktime_get(), stop));
+
+ return ((ioread32(reg) & mask) == value);
+}
+
/**
* crb_go_idle - request tpm crb device to go the idle state
*
@@ -128,7 +147,7 @@ struct tpm2_crb_smc {
*
* Return: 0 always
*/
-static int __maybe_unused crb_go_idle(struct device *dev, struct crb_priv *priv)
+static int crb_go_idle(struct device *dev, struct crb_priv *priv)
{
if ((priv->sm == ACPI_TPM2_START_METHOD) ||
(priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) ||
@@ -136,30 +155,17 @@ static int __maybe_unused crb_go_idle(struct device *dev, struct crb_priv *priv)
return 0;
iowrite32(CRB_CTRL_REQ_GO_IDLE, &priv->regs_t->ctrl_req);
- /* we don't really care when this settles */
+ if (!crb_wait_for_reg_32(&priv->regs_t->ctrl_req,
+ CRB_CTRL_REQ_GO_IDLE/* mask */,
+ 0, /* value */
+ TPM2_TIMEOUT_C)) {
+ dev_warn(dev, "goIdle timed out\n");
+ return -ETIME;
+ }
return 0;
}
-static bool crb_wait_for_reg_32(u32 __iomem *reg, u32 mask, u32 value,
- unsigned long timeout)
-{
- ktime_t start;
- ktime_t stop;
-
- start = ktime_get();
- stop = ktime_add(start, ms_to_ktime(timeout));
-
- do {
- if ((ioread32(reg) & mask) == value)
- return true;
-
- usleep_range(50, 100);
- } while (ktime_before(ktime_get(), stop));
-
- return false;
-}
-
/**
* crb_cmd_ready - request tpm crb device to enter ready state
*
@@ -175,8 +181,7 @@ static bool crb_wait_for_reg_32(u32 __iomem *reg, u32 mask, u32 value,
*
* Return: 0 on success -ETIME on timeout;
*/
-static int __maybe_unused crb_cmd_ready(struct device *dev,
- struct crb_priv *priv)
+static int crb_cmd_ready(struct device *dev, struct crb_priv *priv)
{
if ((priv->sm == ACPI_TPM2_START_METHOD) ||
(priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) ||
@@ -195,11 +200,11 @@ static int __maybe_unused crb_cmd_ready(struct device *dev,
return 0;
}
-static int crb_request_locality(struct tpm_chip *chip, int loc)
+static int __crb_request_locality(struct device *dev,
+ struct crb_priv *priv, 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;
+ CRB_LOC_STATE_TPM_REG_VALID_STS;
if (!priv->regs_h)
return 0;
@@ -207,23 +212,36 @@ static int crb_request_locality(struct tpm_chip *chip, int loc)
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");
+ dev_warn(dev, "TPM_LOC_STATE_x.requestAccess timed out\n");
return -ETIME;
}
return 0;
}
-static void crb_relinquish_locality(struct tpm_chip *chip, int loc)
+static int crb_request_locality(struct tpm_chip *chip, int loc)
{
struct crb_priv *priv = dev_get_drvdata(&chip->dev);
+ return __crb_request_locality(&chip->dev, priv, loc);
+}
+
+static void __crb_relinquish_locality(struct device *dev,
+ struct crb_priv *priv, int loc)
+{
if (!priv->regs_h)
return;
iowrite32(CRB_LOC_CTRL_RELINQUISH, &priv->regs_h->loc_ctrl);
}
+static void crb_relinquish_locality(struct tpm_chip *chip, int loc)
+{
+ struct crb_priv *priv = dev_get_drvdata(&chip->dev);
+
+ __crb_relinquish_locality(&chip->dev, priv, loc);
+}
+
static u8 crb_status(struct tpm_chip *chip)
{
struct crb_priv *priv = dev_get_drvdata(&chip->dev);
@@ -475,6 +493,10 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,
dev_warn(dev, FW_BUG "Bad ACPI memory layout");
}
+ ret = __crb_request_locality(dev, priv, 0);
+ if (ret)
+ return ret;
+
priv->regs_t = crb_map_res(dev, priv, &io_res, buf->control_address,
sizeof(struct crb_regs_tail));
if (IS_ERR(priv->regs_t))
@@ -531,6 +553,8 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,
crb_go_idle(dev, priv);
+ __crb_relinquish_locality(dev, priv, 0);
+
return ret;
}
@@ -588,10 +612,14 @@ static int crb_acpi_add(struct acpi_device *device)
chip->acpi_dev_handle = device->handle;
chip->flags = TPM_CHIP_FLAG_TPM2;
- rc = crb_cmd_ready(dev, priv);
+ rc = __crb_request_locality(dev, priv, 0);
if (rc)
return rc;
+ rc = crb_cmd_ready(dev, priv);
+ if (rc)
+ goto out;
+
pm_runtime_get_noresume(dev);
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
@@ -601,12 +629,15 @@ static int crb_acpi_add(struct acpi_device *device)
crb_go_idle(dev, priv);
pm_runtime_put_noidle(dev);
pm_runtime_disable(dev);
- return rc;
+ goto out;
}
- pm_runtime_put(dev);
+ pm_runtime_put_sync(dev);
- return 0;
+out:
+ __crb_relinquish_locality(dev, priv, 0);
+
+ return rc;
}
static int crb_acpi_remove(struct acpi_device *device)
--
2.14.3
