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    SubjectRE: [tpmdd-devel] [PATCH RFC 3/3] tpm_crb: request and relinquish locality 0
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    >
    > Request and relinquish locality for the driver use in order to be a better citizen
    > in a multi locality environment like with TXT as it uses locality 2.

    >
    > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@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
    > ffd3a6c..9e07cf3 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),
    > @@ -98,12 +107,8 @@ 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
    > */
    > @@ -112,6 +117,7 @@ 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->loc_ctrl);


    Please don't mix different functionalities in one function
    Also those functions are called from runtime pm, this has nothing to do with the power management

    > iowrite32(CRB_CTRL_REQ_GO_IDLE, &priv->regs->ctrl_req);
    > /* we don't really care when this settles */
    >
    > @@ -143,11 +149,8 @@ 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;
    > */
    > @@ -162,7 +165,16 @@ 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->loc_ctrl);
    > + if (!crb_wait_for_reg_32(&priv->regs->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");
    Same here

    > return -ETIME;
    > }
    >
    > --

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