Messages in this thread | | | Date | Sun, 14 Dec 2014 09:48:26 -0500 | From | Stefan Berger <> | Subject | Re: [PATCH v10 8/8] tpm: TPM 2.0 FIFO Interface |
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On 12/12/2014 02:46 PM, Jarkko Sakkinen wrote: > Detect TPM 2.0 by sending idempotent TPM 2.x command. Ordinals for > TPM 2.0 are higher than TPM 1.x commands so this should be fail-safe. > Using STS3 is unreliable because some chips just report 0xff and not > what the spec says.
TPM TIS 1.2 can report either 0xff or 0x00 for sts3 since that part of register was not defined for this version but only for a later version. So, unless the TIS 1.3 for TPM 2.0 is broken, it should report a bit _pattern_ (not plain 0x00 or 0xff) that you could apply the suggested mask to and check then.
Stefan
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