tpm: device class for tpm

Added own device class for TPM. Uses MISC_MAJOR:TPM_MINOR for the
first character device in order to retain backwards compatibility.
Added tpm_dev_release() back attached to the character device.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jasob Gunthorpe <jason.gunthorpe@obsidianresearch.com>
Reviewed-by: Stephan Berger <stephan.berger@linux.vnet.ibm.com>
tpm: TPM 2.0 baseline support

TPM 2.0 devices are separated by adding a field 'flags' to struct
tpm_chip and defining a flag TPM_CHIP_FLAG_TPM2 for tagging them.

This patch adds the following internal functions:

- tpm2_get_random()
- tpm2_get_tpm_pt()
- tpm2_pcr_extend()
- tpm2_pcr_read()
- tpm2_startup()

Additionally, the following exported functions are implemented for
implementing TPM 2.0 device drivers:

- tpm2_do_selftest()
- tpm2_calc_ordinal_durations()
- tpm2_gen_interrupt()

The existing functions that are exported for the use for existing
subsystems have been changed to check the flags field in struct
tpm_chip and use appropriate TPM 2.0 counterpart if
TPM_CHIP_FLAG_TPM2 is est.

The code for tpm2_calc_ordinal_duration() and tpm2_startup() were
originally written by Will Arthur.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Will Arthur <will.c.arthur@intel.com>
Reviewed-by: Jasob Gunthorpe <jason.gunthorpe@obsidianresearch.com>
Reviewed-by: Stephan Berger <stephan.berger@linux.vnet.ibm.com>
tpm: TPM 2.0 CRB Interface

tpm_crb is a driver for TPM 2.0 Command Response Buffer (CRB) Interface
as defined in PC Client Platform TPM Profile (PTP) Specification.

Only polling and single locality is supported as these are the limitations
of the available hardware, Platform Trust Techonlogy (PTT) in Haswell
CPUs.

The driver always applies CRB with ACPI start because PTT reports using
only ACPI start as start method but as a result of my testing it requires
also CRB start.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jasob Gunthorpe <jason.gunthorpe@obsidianresearch.com>
Reviewed-by: Stephan Berger <stephan.berger@linux.vnet.ibm.com>
tpm: TPM 2.0 FIFO Interface

Detect TPM 2.0 by using the extended STS (STS3) register. For TPM 2.0,
instead of calling tpm_get_timeouts(), assign duration and timeout
values defined in the TPM 2.0 PTP specification.

The TPM 2.0 detection was originally implemented by Will Arthur, which
I then extended with power management support and fixing various issues
like requesting locality before detecting TPM (for the case when the
firmware does not initialize the TPM).

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Will Arthur <will.c.arthur@intel.com>
Reviewed-by: Jasob Gunthorpe <jason.gunthorpe@obsidianresearch.com>
Reviewed-by: Stephan Berger <stephan.berger@linux.vnet.ibm.com>