Request and relinquish locality for the driver use in order to be
a better citizen in a multi locality environment like TXT. The
locality is requested and relinquished as part of going into and
waking up from idle.
Signed-off-by: Jarkko Sakkinen <jarkko.sakki...@linux.intel.com>
---
drivers/char/tpm/tpm_crb.c | 36 ++++++++++++++++++++++++------------
1 file changed, 24 insertions(+), 12 deletions(-)
diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c
index 45f53c2..69debe1 100644
--- a/drivers/char/tpm/tpm_crb.c
+++ b/drivers/char/tpm/tpm_crb.c
@@ -34,6 +34,15 @@ 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),
+};
+
enum crb_ctrl_req {
CRB_CTRL_REQ_CMD_READY = BIT(0),
CRB_CTRL_REQ_GO_IDLE = BIT(1),
@@ -101,12 +110,8 @@ struct crb_priv {
* @dev: crb device
* @priv: crb private data
*
- * Write CRB_CTRL_REQ_GO_IDLE to TPM_CRB_CTRL_REQ
- * The device should respond within TIMEOUT_C by clearing the bit.
- * Anyhow, we do not wait here as a consequent CMD_READY request
- * will be handled correctly even if idle was not completed.
- *
- * The function does nothing for devices with ACPI-start method.
+ * Put device to the idle state and relinquish locality. The function does
+ * nothing for devices with the ACPI-start method.
*
* Return: 0 always
*/
@@ -115,6 +120,7 @@ static int __maybe_unused crb_go_idle(struct device *dev,
struct crb_priv *priv)
if (priv->flags & CRB_FL_ACPI_START)
return 0;
+ iowrite32(CRB_LOC_CTRL_RELINQUISH, &priv->regs_h->loc_ctrl);
iowrite32(CRB_CTRL_REQ_GO_IDLE, &priv->regs_t->ctrl_req);
/* we don't really care when this settles */
@@ -146,11 +152,8 @@ static bool crb_wait_for_reg_32(u32 __iomem *reg, u32
mask, u32 value,
* @dev: crb device
* @priv: crb private data
*
- * Write CRB_CTRL_REQ_CMD_READY to TPM_CRB_CTRL_REQ
- * and poll till the device acknowledge it by clearing the bit.
- * The device should respond within TIMEOUT_C.
- *
- * The function does nothing for devices with ACPI-start method
+ * Try to wake up the device and request locality. The function does nothing
+ * for devices with the ACPI-start method.
*
* Return: 0 on success -ETIME on timeout;
*/
@@ -165,7 +168,16 @@ static int __maybe_unused crb_cmd_ready(struct device *dev,
CRB_CTRL_REQ_CMD_READY /* mask */,
0, /* value */
TPM2_TIMEOUT_C)) {
- dev_warn(dev, "cmdReady timed out\n");
+ dev_warn(dev, "TPM_CRB_CTRL_REQ_x.cmdReady timed out\n");
+ return -ETIME;
+ }
+
+ iowrite32(CRB_LOC_CTRL_REQUEST_ACCESS, &priv->regs_h->loc_ctrl);
+ if (!crb_wait_for_reg_32(&priv->regs_h->loc_state,
+ CRB_LOC_STATE_LOC_ASSIGNED, /* mask */
+ CRB_LOC_STATE_LOC_ASSIGNED, /* value */
+ TPM2_TIMEOUT_C)) {
+ dev_warn(dev, "TPM_LOC_STATE_x.requestAccess timed out\n");
return -ETIME;
}
--
2.7.4
