1What: /sys/devices/pnp0/<bus-num>/ppi/ 2Date: August 2012 3Kernel Version: 3.6 4Contact: xiaoyan.zhang@intel.com 5Description: 6 This folder includes the attributes related with PPI (Physical 7 Presence Interface). Only if TPM is supported by BIOS, this 8 folder makes sense. The folder path can be got by command 9 'find /sys/ -name 'pcrs''. For the detail information of PPI, 10 please refer to the PPI specification from 11 http://www.trustedcomputinggroup.org/ 12 13What: /sys/devices/pnp0/<bus-num>/ppi/version 14Date: August 2012 15Contact: xiaoyan.zhang@intel.com 16Description: 17 This attribute shows the version of the PPI supported by the 18 platform. 19 This file is readonly. 20 21What: /sys/devices/pnp0/<bus-num>/ppi/request 22Date: August 2012 23Contact: xiaoyan.zhang@intel.com 24Description: 25 This attribute shows the request for an operation to be 26 executed in the pre-OS environment. It is the only input from 27 the OS to the pre-OS environment. The request should be an 28 integer value range from 1 to 160, and 0 means no request. 29 This file can be read and written. 30 31What: /sys/devices/pnp0/00:<bus-num>/ppi/response 32Date: August 2012 33Contact: xiaoyan.zhang@intel.com 34Description: 35 This attribute shows the response to the most recent operation 36 request it acted upon. The format is "<request> <response num> 37 : <response description>". 38 This file is readonly. 39 40What: /sys/devices/pnp0/<bus-num>/ppi/transition_action 41Date: August 2012 42Contact: xiaoyan.zhang@intel.com 43Description: 44 This attribute shows the platform-specific action that should 45 take place in order to transition to the BIOS for execution of 46 a requested operation. The format is "<action num>: <action 47 description>". 48 This file is readonly. 49 50What: /sys/devices/pnp0/<bus-num>/ppi/tcg_operations 51Date: August 2012 52Contact: xiaoyan.zhang@intel.com 53Description: 54 This attribute shows whether it is allowed to request an 55 operation to be executed in the pre-OS environment by the BIOS 56 for the requests defined by TCG, i.e. requests from 1 to 22. 57 The format is "<request> <status num>: <status description>". 58 This attribute is only supported by PPI version 1.2+. 59 This file is readonly. 60 61What: /sys/devices/pnp0/<bus-num>/ppi/vs_operations 62Date: August 2012 63Contact: xiaoyan.zhang@intel.com 64Description: 65 This attribute shows whether it is allowed to request an 66 operation to be executed in the pre-OS environment by the BIOS 67 for the verdor specific requests, i.e. requests from 128 to 68 255. The format is same with tcg_operations. This attribute 69 is also only supported by PPI version 1.2+. 70 This file is readonly. 71