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Date:   Wed, 17 Jun 2020 04:01:03 +0300
From:   Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To:     amirmizi6@gmail.com
Cc:     Eyal.Cohen@nuvoton.com, oshrialkoby85@gmail.com,
        alexander.steffen@infineon.com, robh+dt@kernel.org,
        peterhuewe@gmx.de, christophe-h.richard@st.com, jgg@ziepe.ca,
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        Dan.Morav@nuvoton.com, oren.tanami@nuvoton.com,
        shmulik.hager@nuvoton.com, amir.mizinski@nuvoton.com,
        Benoit Houyere <benoit.houyere@st.com>
Subject: Re: [PATCH v10 2/8] tpm: tpm_tis: Fix expected bit handling and send
 all bytes in one shot without last byte in exception
Message-ID: <20200617010050.GA5100@linux.intel.com>
References: <20200604134713.157951-1-amirmizi6@gmail.com>
 <20200604134713.157951-3-amirmizi6@gmail.com>
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On Thu, Jun 04, 2020 at 04:47:07PM +0300, amirmizi6@gmail.com wrote:
> From: Amir Mizinski <amirmizi6@gmail.com>
> 
> Detected the following incorrect implementation of the send command:
> polling on the TPM_STS.stsValid field followed by checking the
> TPM_STS.expect field only once. Since TPM_STS.stsValid represents the
> TPM_STS.expect validity, both fields should be polled at the same time.
> 
> This fix modifies the signature of wait_for_tpm_stat(), adding an
> additional "mask_result" parameter to its call. wait_for_tpm_stat() is now
> polling the TPM_STS with a mask and waits for the value in mask_result.
> The fix adds the ability to check if certain TPM_STS bits have been
> cleared.
> 
> This change is also aligned to verifying the CRC on I2C TPM. The CRC
> verification should be done after the TPM_STS.expect field is cleared
> (TPM received all expected command bytes and set the calculated CRC value
> in the register).
> 
> In addition, the send command was changed to comply with
> TCG_DesignPrinciples_TPM2p0Driver_vp24_pubrev.pdf as follows:
> - send all command bytes in one loop
> - remove special handling of the last byte
> 
> Suggested-by: Benoit Houyere <benoit.houyere@st.com>
> Signed-off-by: Amir Mizinski <amirmizi6@gmail.com>

Just wondering how did you come up with that name since you are not
masking anything with 'mask_result'?

/Jarkko