Re: [PATCH 1/2] tpm_tis: Use tpm_chip_{start,stop} decoration inside tpm_tis_resume

On Wed, Apr 26, 2023 at 08:29:27PM +0300, Jarkko Sakkinen wrote:

Before sending a TPM command, CLKRUN protocol must be disabled. This is not done in the case of tpm1_do_selftest() call site inside tpm_tis_resume().

Address this by decorating the calls with tpm_chip_{start,stop}, which arm and disarm the TPM chip for transmission, and take care of disabling and re-enabling CLKRUN, among other things.

Cc: stable@vger.kernel.org Reported-by: Jason A. Donenfeld Jason@zx2c4.com Link: https://lore.kernel.org/linux-integrity/CS68AWILHXS4.3M36M1EKZLUMS@suppilova... Fixes: a3fbfae82b4c ("tpm: take TPM chip power gating out of tpm_transmit()") Signed-off-by: Jarkko Sakkinen jarkko@kernel.org

---

drivers/char/tpm/tpm_tis_core.c | 43 +++++++++++++++------------------ 1 file changed, 19 insertions(+), 24 deletions(-)

Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index c2421162cf34..73707026e358 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -1209,25 +1209,20 @@ static void tpm_tis_reenable_interrupts(struct tpm_chip *chip) u32 intmask; int rc;

• if (chip->ops->clk_enable != NULL)

• chip->ops->clk_enable(chip, true);
  

• /* reenable interrupts that device may have lost or

• * BIOS/firmware may have disabled
  

• /*

• * Re-enable interrupts that device may have lost or BIOS/firmware may
  

• * have disabled.
  

  */ rc = tpm_tis_write8(priv, TPM_INT_VECTOR(priv->locality), priv->irq);

• if (rc < 0)

• goto out;
  

• if (rc < 0) {

• dev_err(&chip->dev, "Setting IRQ failed.\n");
  

• return;
  

• }

intmask = priv->int_mask | TPM_GLOBAL_INT_ENABLE;

• tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);

-out:

• if (chip->ops->clk_enable != NULL)

• chip->ops->clk_enable(chip, false);
  

• return;

• rc = tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
• if (rc < 0)

• dev_err(&chip->dev, "Enabling interrupts failed.\n");
  

} int tpm_tis_resume(struct device *dev) @@ -1235,27 +1230,27 @@ int tpm_tis_resume(struct device *dev) struct tpm_chip *chip = dev_get_drvdata(dev); int ret;

• ret = tpm_tis_request_locality(chip, 0);
• if (ret < 0)

• ret = tpm_chip_start(chip);
• if (ret) return ret;

if (chip->flags & TPM_CHIP_FLAG_IRQ) tpm_tis_reenable_interrupts(chip);

• ret = tpm_pm_resume(dev);
• if (ret)

• goto out;
  

• /*
  • TPM 1.2 requires self-test on resume. This function actually returns
  • an error code but for unknown reason it isn't handled.
  */ if (!(chip->flags & TPM_CHIP_FLAG_TPM2)) tpm1_do_selftest(chip);

-out:

• tpm_tis_relinquish_locality(chip, 0);

• return ret;

• tpm_chip_stop(chip);
• ret = tpm_pm_resume(dev);
• if (ret)

• return ret;
  

• return 0;

} EXPORT_SYMBOL_GPL(tpm_tis_resume);

#endif

2.39.2