On Tue, May 26, 2020 at 05:16:52PM +0300, amirmizi6@xxxxxxxxx wrote: > From: Amir Mizinski <amirmizi6@xxxxxxxxx> > > Incorrect implementation of send message was detected. We polled only > TPM_STS.stsValid bit and then we single-checked the TPM_STS.expect bit > value. > TPM_STS.expected bit should be checked at the same time as > TPM_STS.stsValid bit, and this should be repeated until timeout_A. I don't understand what the first paragraph is trying to say. It does not conclude to anything. Please write instead soemthing that explains what is going on. > To detect a TPM_STS.expected bit reset, the "wait_for_tpm_stat" function is > modified to "wait_for_tpm_stat_result". This function regularly reads the > status register and check the bits defined by "mask" to reach the value > defined in "mask_result". Please remove this and explain instead how are you are changing the existing function. > This correct implementation is required for using the new CRC calculation > on I2C TPM command bytes or I2C TPM answer bytes. TPM_STS.expected bit is > reset after all bytes are acquired and the CRC result is inserted in the > dedicated register. It introduces a normal latency for TPM_STS.expected > bit reset. > > Respectively, to send a message, as defined in > TCG_DesignPrinciples_TPM2p0Driver_vp24_pubrev.pdf, all bytes should be > sent in one shot instead of sending the last byte separately. > > Suggested-by: Benoit Houyere <benoit.houyere@xxxxxx> > Signed-off-by: Amir Mizinski <amirmizi6@xxxxxxxxx> > --- > drivers/char/tpm/tpm_tis_core.c | 74 +++++++++++++++++------------------------ > 1 file changed, 30 insertions(+), 44 deletions(-) > > diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c > index 27c6ca0..c725b68 100644 > --- a/drivers/char/tpm/tpm_tis_core.c > +++ b/drivers/char/tpm/tpm_tis_core.c > @@ -44,9 +44,10 @@ static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask, > return false; > } > > -static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, > - unsigned long timeout, wait_queue_head_t *queue, > - bool check_cancel) > +static int wait_for_tpm_stat_result(struct tpm_chip *chip, u8 mask, > + u8 mask_result, unsigned long timeout, > + wait_queue_head_t *queue, > + bool check_cancel) Please do not change the function name. /Jarkko
