1*b8e98dcdSJarkko SakkinenWhat: /sys/class/tpm/tpmX/ppi/ 21f862f0fSXiaoyan ZhangDate: August 2012 31f862f0fSXiaoyan ZhangKernelVersion: 3.6 41f862f0fSXiaoyan ZhangContact: xiaoyan.zhang@intel.com 51f862f0fSXiaoyan ZhangDescription: 61f862f0fSXiaoyan Zhang This folder includes the attributes related with PPI (Physical 71f862f0fSXiaoyan Zhang Presence Interface). Only if TPM is supported by BIOS, this 84e79162aSMasanari Iida folder makes sense. The folder path can be got by command 91f862f0fSXiaoyan Zhang 'find /sys/ -name 'pcrs''. For the detail information of PPI, 101f862f0fSXiaoyan Zhang please refer to the PPI specification from 11*b8e98dcdSJarkko Sakkinen 121f862f0fSXiaoyan Zhang http://www.trustedcomputinggroup.org/ 131f862f0fSXiaoyan Zhang 14*b8e98dcdSJarkko Sakkinen In Linux 4.2 ppi was moved to the character device directory. 15*b8e98dcdSJarkko Sakkinen A symlink from tpmX/device/ppi to tpmX/ppi to provide backwards 16*b8e98dcdSJarkko Sakkinen compatibility. 17*b8e98dcdSJarkko Sakkinen 18*b8e98dcdSJarkko SakkinenWhat: /sys/class/tpm/tpmX/ppi/version 191f862f0fSXiaoyan ZhangDate: August 2012 201f862f0fSXiaoyan ZhangContact: xiaoyan.zhang@intel.com 211f862f0fSXiaoyan ZhangDescription: 221f862f0fSXiaoyan Zhang This attribute shows the version of the PPI supported by the 231f862f0fSXiaoyan Zhang platform. 241f862f0fSXiaoyan Zhang This file is readonly. 251f862f0fSXiaoyan Zhang 26*b8e98dcdSJarkko SakkinenWhat: /sys/class/tpm/tpmX/ppi/request 271f862f0fSXiaoyan ZhangDate: August 2012 281f862f0fSXiaoyan ZhangContact: xiaoyan.zhang@intel.com 291f862f0fSXiaoyan ZhangDescription: 301f862f0fSXiaoyan Zhang This attribute shows the request for an operation to be 311f862f0fSXiaoyan Zhang executed in the pre-OS environment. It is the only input from 321f862f0fSXiaoyan Zhang the OS to the pre-OS environment. The request should be an 331f862f0fSXiaoyan Zhang integer value range from 1 to 160, and 0 means no request. 341f862f0fSXiaoyan Zhang This file can be read and written. 351f862f0fSXiaoyan Zhang 36*b8e98dcdSJarkko SakkinenWhat: /sys/class/tpm/tpmX/ppi/response 371f862f0fSXiaoyan ZhangDate: August 2012 381f862f0fSXiaoyan ZhangContact: xiaoyan.zhang@intel.com 391f862f0fSXiaoyan ZhangDescription: 401f862f0fSXiaoyan Zhang This attribute shows the response to the most recent operation 411f862f0fSXiaoyan Zhang request it acted upon. The format is "<request> <response num> 421f862f0fSXiaoyan Zhang : <response description>". 431f862f0fSXiaoyan Zhang This file is readonly. 441f862f0fSXiaoyan Zhang 45*b8e98dcdSJarkko SakkinenWhat: /sys/class/tpm/tpmX/ppi/transition_action 461f862f0fSXiaoyan ZhangDate: August 2012 471f862f0fSXiaoyan ZhangContact: xiaoyan.zhang@intel.com 481f862f0fSXiaoyan ZhangDescription: 491f862f0fSXiaoyan Zhang This attribute shows the platform-specific action that should 501f862f0fSXiaoyan Zhang take place in order to transition to the BIOS for execution of 511f862f0fSXiaoyan Zhang a requested operation. The format is "<action num>: <action 521f862f0fSXiaoyan Zhang description>". 531f862f0fSXiaoyan Zhang This file is readonly. 541f862f0fSXiaoyan Zhang 55*b8e98dcdSJarkko SakkinenWhat: /sys/class/tpm/tpmX/ppi/tcg_operations 561f862f0fSXiaoyan ZhangDate: August 2012 571f862f0fSXiaoyan ZhangContact: xiaoyan.zhang@intel.com 581f862f0fSXiaoyan ZhangDescription: 591f862f0fSXiaoyan Zhang This attribute shows whether it is allowed to request an 601f862f0fSXiaoyan Zhang operation to be executed in the pre-OS environment by the BIOS 611f862f0fSXiaoyan Zhang for the requests defined by TCG, i.e. requests from 1 to 22. 621f862f0fSXiaoyan Zhang The format is "<request> <status num>: <status description>". 631f862f0fSXiaoyan Zhang This attribute is only supported by PPI version 1.2+. 641f862f0fSXiaoyan Zhang This file is readonly. 651f862f0fSXiaoyan Zhang 66*b8e98dcdSJarkko SakkinenWhat: /sys/class/tpm/tpmX/ppi/vs_operations 671f862f0fSXiaoyan ZhangDate: August 2012 681f862f0fSXiaoyan ZhangContact: xiaoyan.zhang@intel.com 691f862f0fSXiaoyan ZhangDescription: 701f862f0fSXiaoyan Zhang This attribute shows whether it is allowed to request an 711f862f0fSXiaoyan Zhang operation to be executed in the pre-OS environment by the BIOS 721f862f0fSXiaoyan Zhang for the verdor specific requests, i.e. requests from 128 to 731f862f0fSXiaoyan Zhang 255. The format is same with tcg_operations. This attribute 741f862f0fSXiaoyan Zhang is also only supported by PPI version 1.2+. 751f862f0fSXiaoyan Zhang This file is readonly. 76