diff options
Diffstat (limited to 'Documentation/ABI/testing/sysfs-driver-ppi')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-driver-ppi | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-driver-ppi b/Documentation/ABI/testing/sysfs-driver-ppi new file mode 100644 index 000000000..9921ef285 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-driver-ppi @@ -0,0 +1,75 @@ +What: /sys/class/tpm/tpmX/ppi/ +Date: August 2012 +Kernel Version: 3.6 +Contact: xiaoyan.zhang@intel.com +Description: + This folder includes the attributes related with PPI (Physical + Presence Interface). Only if TPM is supported by BIOS, this + folder makes sense. The folder path can be got by command + 'find /sys/ -name 'pcrs''. For the detail information of PPI, + please refer to the PPI specification from + + http://www.trustedcomputinggroup.org/ + + In Linux 4.2 ppi was moved to the character device directory. + A symlink from tpmX/device/ppi to tpmX/ppi to provide backwards + compatibility. + +What: /sys/class/tpm/tpmX/ppi/version +Date: August 2012 +Contact: xiaoyan.zhang@intel.com +Description: + This attribute shows the version of the PPI supported by the + platform. + This file is readonly. + +What: /sys/class/tpm/tpmX/ppi/request +Date: August 2012 +Contact: xiaoyan.zhang@intel.com +Description: + This attribute shows the request for an operation to be + executed in the pre-OS environment. It is the only input from + the OS to the pre-OS environment. The request should be an + integer value range from 1 to 160, and 0 means no request. + This file can be read and written. + +What: /sys/class/tpm/tpmX/ppi/response +Date: August 2012 +Contact: xiaoyan.zhang@intel.com +Description: + This attribute shows the response to the most recent operation + request it acted upon. The format is "<request> <response num> + : <response description>". + This file is readonly. + +What: /sys/class/tpm/tpmX/ppi/transition_action +Date: August 2012 +Contact: xiaoyan.zhang@intel.com +Description: + This attribute shows the platform-specific action that should + take place in order to transition to the BIOS for execution of + a requested operation. The format is "<action num>: <action + description>". + This file is readonly. + +What: /sys/class/tpm/tpmX/ppi/tcg_operations +Date: August 2012 +Contact: xiaoyan.zhang@intel.com +Description: + This attribute shows whether it is allowed to request an + operation to be executed in the pre-OS environment by the BIOS + for the requests defined by TCG, i.e. requests from 1 to 22. + The format is "<request> <status num>: <status description>". + This attribute is only supported by PPI version 1.2+. + This file is readonly. + +What: /sys/class/tpm/tpmX/ppi/vs_operations +Date: August 2012 +Contact: xiaoyan.zhang@intel.com +Description: + This attribute shows whether it is allowed to request an + operation to be executed in the pre-OS environment by the BIOS + for the verdor specific requests, i.e. requests from 128 to + 255. The format is same with tcg_operations. This attribute + is also only supported by PPI version 1.2+. + This file is readonly. |