1 What: /sys/devices/pnp0/<bus-num>/ppi/
4 Contact: xiaoyan.zhang@intel.com
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/
13 What: /sys/devices/pnp0/<bus-num>/ppi/version
15 Contact: xiaoyan.zhang@intel.com
17 This attribute shows the version of the PPI supported by the
19 This file is readonly.
21 What: /sys/devices/pnp0/<bus-num>/ppi/request
23 Contact: xiaoyan.zhang@intel.com
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.
31 What: /sys/devices/pnp0/00:<bus-num>/ppi/response
33 Contact: xiaoyan.zhang@intel.com
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.
40 What: /sys/devices/pnp0/<bus-num>/ppi/transition_action
42 Contact: xiaoyan.zhang@intel.com
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
48 This file is readonly.
50 What: /sys/devices/pnp0/<bus-num>/ppi/tcg_operations
52 Contact: xiaoyan.zhang@intel.com
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.
61 What: /sys/devices/pnp0/<bus-num>/ppi/vs_operations
63 Contact: xiaoyan.zhang@intel.com
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.