On Wed, Jul 13, 2016 at 09:19:35AM -0700, Ed Swierk wrote:
> Some TPM chips report bogus command durations in their capabilities,
> just as others report incorrect timeouts. Rework tpm_get_timeouts() to
> allow chip drivers to override either via a single callback. Also
> clean up handling of TPMs that report milliseconds instead of
> microseconds.

I don't really undestand why you need to turn things so much over.
There's too much noise in this commit to reasonably evaluate it.

> Signed-off-by: Ed Swierk <eswi...@skyportsystems.com>
> ---
>  drivers/char/tpm/tpm-interface.c | 148 
> ++++++++++++++++++++++-----------------
>  drivers/char/tpm/tpm_tis_core.c  |  32 +++------
>  include/linux/tpm.h              |   3 +-
>  3 files changed, 94 insertions(+), 89 deletions(-)
> 
> diff --git a/drivers/char/tpm/tpm-interface.c 
> b/drivers/char/tpm/tpm-interface.c
> index dc492ee..9dafc25 100644
> --- a/drivers/char/tpm/tpm-interface.c
> +++ b/drivers/char/tpm/tpm-interface.c
> @@ -513,10 +513,10 @@ static int tpm_startup(struct tpm_chip *chip, __be16 
> startup_type)
>  
>  int tpm_get_timeouts(struct tpm_chip *chip)
>  {
> -     cap_t cap;

cap_t cap2;

> -     unsigned long new_timeout[4];
> -     unsigned long old_timeout[4];
> -     ssize_t rc;
> +     cap_t cap1, cap2;

Do not use cap1.

> +     int rc;
> +     unsigned long orig_timeout_a, orig_timeout_b, orig_timeout_c,
> +             orig_timeout_d, orig_duration[3];

Use old_timeout array just to reduce the diff.

>  
>       if (chip->flags & TPM_CHIP_FLAG_TPM2) {
>               /* Fixed timeouts for TPM2 */
> @@ -533,7 +533,7 @@ int tpm_get_timeouts(struct tpm_chip *chip)
>               return 0;
>       }
>  
> -     rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
> +     rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap1,
>                       "attempting to determine the timeouts");
>       if (rc == TPM_ERR_INVALID_POSTINIT) {
>               /* The TPM is not started, we are the first to talk to it.
> @@ -542,77 +542,95 @@ int tpm_get_timeouts(struct tpm_chip *chip)
>               if (tpm_startup(chip, TPM_ST_CLEAR))
>                       return rc;
>  
> -             rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
> +             rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap1,
>                               "attempting to determine the timeouts");
>       }
>       if (rc)
>               return rc;
>  
> -     old_timeout[0] = be32_to_cpu(cap.timeout.a);
> -     old_timeout[1] = be32_to_cpu(cap.timeout.b);
> -     old_timeout[2] = be32_to_cpu(cap.timeout.c);
> -     old_timeout[3] = be32_to_cpu(cap.timeout.d);
> -     memcpy(new_timeout, old_timeout, sizeof(new_timeout));
> -
> -     /*
> -      * Provide ability for vendor overrides of timeout values in case
> -      * of misreporting.
> -      */
> -     if (chip->ops->update_timeouts != NULL)
> -             chip->timeout_adjusted =
> -                     chip->ops->update_timeouts(chip, new_timeout);
> -
> -     if (!chip->timeout_adjusted) {
> -             /* Don't overwrite default if value is 0 */
> -             if (new_timeout[0] != 0 && new_timeout[0] < 1000) {
> -                     int i;
> -
> -                     /* timeouts in msec rather usec */
> -                     for (i = 0; i != ARRAY_SIZE(new_timeout); i++)
> -                             new_timeout[i] *= 1000;
> -                     chip->timeout_adjusted = true;
> -             }
> -     }
> -
> -     /* Report adjusted timeouts */
> -     if (chip->timeout_adjusted) {
> -             dev_info(&chip->dev,
> -                      HW_ERR "Adjusting reported timeouts: A %lu->%luus B 
> %lu->%luus C %lu->%luus D %lu->%luus\n",
> -                      old_timeout[0], new_timeout[0],
> -                      old_timeout[1], new_timeout[1],
> -                      old_timeout[2], new_timeout[2],
> -                      old_timeout[3], new_timeout[3]);
> -     }
> -
> -     chip->timeout_a = usecs_to_jiffies(new_timeout[0]);
> -     chip->timeout_b = usecs_to_jiffies(new_timeout[1]);
> -     chip->timeout_c = usecs_to_jiffies(new_timeout[2]);
> -     chip->timeout_d = usecs_to_jiffies(new_timeout[3]);
> -
> -     rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap,
> +     rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap2,
>                       "attempting to determine the durations");
>       if (rc)
>               return rc;
>  
> -     chip->duration[TPM_SHORT] =
> -             usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_short));
> -     chip->duration[TPM_MEDIUM] =
> -             usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium));
> -     chip->duration[TPM_LONG] =
> -             usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long));
> +     be32_to_cpus(&cap1.timeout.a);
> +     be32_to_cpus(&cap1.timeout.b);
> +     be32_to_cpus(&cap1.timeout.c);
> +     be32_to_cpus(&cap1.timeout.d);
> +     chip->timeout_a = usecs_to_jiffies(cap1.timeout.a);
> +     chip->timeout_b = usecs_to_jiffies(cap1.timeout.b);
> +     chip->timeout_c = usecs_to_jiffies(cap1.timeout.c);
> +     chip->timeout_d = usecs_to_jiffies(cap1.timeout.d);
>  
> -     /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
> -      * value wrong and apparently reports msecs rather than usecs. So we
> -      * fix up the resulting too-small TPM_SHORT value to make things work.
> -      * We also scale the TPM_MEDIUM and -_LONG values by 1000.
> -      */
> -     if (chip->duration[TPM_SHORT] < (HZ / 100)) {
> -             chip->duration[TPM_SHORT] = HZ;
> -             chip->duration[TPM_MEDIUM] *= 1000;
> -             chip->duration[TPM_LONG] *= 1000;
> -             chip->duration_adjusted = true;
> -             dev_info(&chip->dev, "Adjusting TPM timeout parameters.");
> +     /* Some TPMs report timeouts in milliseconds rather than
> +        microseconds. Use a value between 1 and 1000 as an
> +        indication that this is the case. */
> +     if (cap1.timeout.a > 0 && cap1.timeout.a < 1000) {
> +             chip->timeout_a = msecs_to_jiffies(cap1.timeout.a);
> +             chip->timeout_b = msecs_to_jiffies(cap1.timeout.b);
> +             chip->timeout_c = msecs_to_jiffies(cap1.timeout.c);
> +             chip->timeout_d = msecs_to_jiffies(cap1.timeout.d);
> +             chip->timeout_adjusted = true;
>       }
> +
> +     be32_to_cpus(&cap2.duration.tpm_short);
> +     be32_to_cpus(&cap2.duration.tpm_medium);
> +     be32_to_cpus(&cap2.duration.tpm_long);
> +     chip->duration[TPM_SHORT] =
> +             usecs_to_jiffies(cap2.duration.tpm_short);
> +     chip->duration[TPM_MEDIUM] =
> +             usecs_to_jiffies(cap2.duration.tpm_medium);
> +     chip->duration[TPM_LONG] =
> +             usecs_to_jiffies(cap2.duration.tpm_long);
> +
> +     orig_timeout_a = chip->timeout_a;
> +     orig_timeout_b = chip->timeout_b;
> +     orig_timeout_c = chip->timeout_c;
> +     orig_timeout_d = chip->timeout_d;
> +     memcpy(orig_duration, chip->duration, 3 * sizeof(unsigned long));
> +
> +     /* Interpret duration values between 1 and 10000 as
> +        milliseconds to deal with TPMs like the Broadcom BCM0102 in
> +        the Dell Latitude D820. */
> +     if (cap2.duration.tpm_short > 0 && cap2.duration.tpm_short < 10000) {
> +             chip->duration[TPM_SHORT] =
> +                     msecs_to_jiffies(cap2.duration.tpm_short);
> +             chip->duration[TPM_MEDIUM] =
> +                     msecs_to_jiffies(cap2.duration.tpm_medium);
> +             chip->duration[TPM_LONG] =
> +                     msecs_to_jiffies(cap2.duration.tpm_long);
> +             chip->duration_adjusted = true;
> +     }
> +
> +     if (chip->ops->update_timeouts != NULL)
> +             chip->ops->update_timeouts(chip);
> +
> +     if (chip->timeout_adjusted) {
> +             dev_info(&chip->dev,
> +                      HW_ERR "Adjusted timeouts: A %u->%uus B %u->%uus"
> +                      " C %u->%uus D %u->%uus\n",
> +                      jiffies_to_usecs(orig_timeout_a),
> +                      jiffies_to_usecs(chip->timeout_a),
> +                      jiffies_to_usecs(orig_timeout_b),
> +                      jiffies_to_usecs(chip->timeout_b),
> +                      jiffies_to_usecs(orig_timeout_c),
> +                      jiffies_to_usecs(chip->timeout_c),
> +                      jiffies_to_usecs(orig_timeout_d),
> +                      jiffies_to_usecs(chip->timeout_d));
> +     }
> +
> +     if (chip->duration_adjusted) {
> +             dev_info(&chip->dev,
> +                      HW_ERR "Adjusted durations: short %u->%uus"
> +                      " medium %u->%uus long %u->%uus\n",
> +                      jiffies_to_usecs(orig_duration[TPM_SHORT]),
> +                      jiffies_to_usecs(chip->duration[TPM_SHORT]),
> +                      jiffies_to_usecs(orig_duration[TPM_MEDIUM]),
> +                      jiffies_to_usecs(chip->duration[TPM_MEDIUM]),
> +                      jiffies_to_usecs(orig_duration[TPM_LONG]),
> +                      jiffies_to_usecs(chip->duration[TPM_LONG]));
> +     }
> +
>       return 0;
>  }
>  EXPORT_SYMBOL_GPL(tpm_get_timeouts);
> diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
> index e62fdeb..f013664 100644
> --- a/drivers/char/tpm/tpm_tis_core.c
> +++ b/drivers/char/tpm/tpm_tis_core.c
> @@ -398,37 +398,25 @@ static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, 
> size_t len)
>       return rc;
>  }
>  
> -struct tis_vendor_timeout_override {
> -     u32 did_vid;
> -     unsigned long timeout_us[4];
> -};
> -
> -static const struct tis_vendor_timeout_override vendor_timeout_overrides[] = 
> {
> -     /* Atmel 3204 */
> -     { 0x32041114, { (TIS_SHORT_TIMEOUT*1000), (TIS_LONG_TIMEOUT*1000),
> -                     (TIS_SHORT_TIMEOUT*1000), (TIS_SHORT_TIMEOUT*1000) } },
> -};
> -
> -static bool tpm_tis_update_timeouts(struct tpm_chip *chip,
> -                                 unsigned long *timeout_cap)
> +static void tpm_tis_update_timeouts(struct tpm_chip *chip)
>  {
>       struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
> -     int i, rc;
> +     int rc;
>       u32 did_vid;
>  
>       rc = tpm_tis_read32(priv, TPM_DID_VID(0), &did_vid);
>       if (rc < 0)
>               return rc;
>  
> -     for (i = 0; i != ARRAY_SIZE(vendor_timeout_overrides); i++) {
> -             if (vendor_timeout_overrides[i].did_vid != did_vid)
> -                     continue;
> -             memcpy(timeout_cap, vendor_timeout_overrides[i].timeout_us,
> -                    sizeof(vendor_timeout_overrides[i].timeout_us));
> -             return true;
> +     switch (did_vid) {
> +     case 0x32041114: /* Atmel 3204 */
> +             chip->timeout_a = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
> +             chip->timeout_b = msecs_to_jiffies(TIS_LONG_TIMEOUT);
> +             chip->timeout_c = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
> +             chip->timeout_d = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
> +             chip->timeout_adjusted = true;
> +             break;

Is this needed if we have the special case for milliseconds in
tpm_get_timeouts?

>       }
> -
> -     return false;
>  }
>  
>  /*
> diff --git a/include/linux/tpm.h b/include/linux/tpm.h
> index 706e63e..2380ebf 100644
> --- a/include/linux/tpm.h
> +++ b/include/linux/tpm.h
> @@ -41,8 +41,7 @@ struct tpm_class_ops {
>       int (*send) (struct tpm_chip *chip, u8 *buf, size_t len);
>       void (*cancel) (struct tpm_chip *chip);
>       u8 (*status) (struct tpm_chip *chip);
> -     bool (*update_timeouts)(struct tpm_chip *chip,
> -                             unsigned long *timeout_cap);
> +     void (*update_timeouts)(struct tpm_chip *chip);
>  
>  };
>  
> -- 
> 1.9.1
> 

/Jarkko

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