> CC linux-security-module
>
> On Sat, Dec 03, 2016 at 07:52:12PM +0200, Jarkko Sakkinen wrote:
> > Encapsulated crb_wait_for_reg32() so that state changes in other CRB
> > registers than TPM_CRB_CTRL_REQ_x can be waited.
> >
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakki...@linux.intel.com>
> > ---
> > drivers/char/tpm/tpm_crb.c | 37 +++++++++++++++++++++++--------------
> > 1 file changed, 23 insertions(+), 14 deletions(-)
> >
> > diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c
> > index 8d81b66..f986d02 100644
> > --- a/drivers/char/tpm/tpm_crb.c
> > +++ b/drivers/char/tpm/tpm_crb.c
> > @@ -121,6 +121,25 @@ static int __maybe_unused crb_go_idle(struct
> device *dev, struct crb_priv *priv)
> > 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);
This was tuned for power management, have you tuned it for locality?
> > + } while (ktime_before(ktime_get(), stop));
> > +
> > + return false;
> > +}
> > +
> > /**
> > * crb_cmd_ready - request tpm crb device to enter ready state
> > *
> > @@ -138,24 +157,14 @@ static int __maybe_unused crb_go_idle(struct
> > device *dev, struct crb_priv *priv) static int __maybe_unused
> crb_cmd_ready(struct device *dev,
> > struct crb_priv *priv)
> > {
> > - ktime_t stop, start;
> > - u32 req;
> > -
> > if (priv->flags & CRB_FL_ACPI_START)
> > return 0;
> >
> > iowrite32(CRB_CTRL_REQ_CMD_READY, &priv->regs_t->ctrl_req);
> > -
> > - start = ktime_get();
> > - stop = ktime_add(start, ms_to_ktime(TPM2_TIMEOUT_C));
> > - do {
> > - req = ioread32(&priv->regs_t->ctrl_req);
> > - if (!(req & CRB_CTRL_REQ_CMD_READY))
> > - return 0;
> > - usleep_range(50, 100);
> > - } while (ktime_before(ktime_get(), stop));
> > -
> > - if (ioread32(&priv->regs_t->ctrl_req) & CRB_CTRL_REQ_CMD_READY)
> {
> > + if (!crb_wait_for_reg_32(&priv->regs_t->ctrl_req,
> > + CRB_CTRL_REQ_CMD_READY /* mask */,
> > + 0, /* value */
> > + TPM2_TIMEOUT_C)) {
> > dev_warn(dev, "cmdReady timed out\n");
> > return -ETIME;
> > }
> > --
> > 2.9.3
> >
>
> ------------------------------------------------------------------------------
> Check out the vibrant tech community on one of the world's most
> engaging tech sites, SlashDot.org! http://sdm.link/slashdot
> _______________________________________________
> tpmdd-devel mailing list
> tpmdd-de...@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/tpmdd-devel
