xref: /aosp_15_r20/external/ms-tpm-20-ref/TPMCmd/Platform/src/PowerPlat.c (revision 5c591343844d1f9da7da26467c4bf7efc8a7a413)
1 /* Microsoft Reference Implementation for TPM 2.0
2  *
3  *  The copyright in this software is being made available under the BSD License,
4  *  included below. This software may be subject to other third party and
5  *  contributor rights, including patent rights, and no such rights are granted
6  *  under this license.
7  *
8  *  Copyright (c) Microsoft Corporation
9  *
10  *  All rights reserved.
11  *
12  *  BSD License
13  *
14  *  Redistribution and use in source and binary forms, with or without modification,
15  *  are permitted provided that the following conditions are met:
16  *
17  *  Redistributions of source code must retain the above copyright notice, this list
18  *  of conditions and the following disclaimer.
19  *
20  *  Redistributions in binary form must reproduce the above copyright notice, this
21  *  list of conditions and the following disclaimer in the documentation and/or
22  *  other materials provided with the distribution.
23  *
24  *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ""AS IS""
25  *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
27  *  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
28  *  ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
29  *  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
30  *  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
31  *  ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32  *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 //** Includes and Function Prototypes
36 
37 #include    "Platform.h"
38 #include    "_TPM_Init_fp.h"
39 
40 //** Functions
41 
42 //***_plat__Signal_PowerOn()
43 // Signal platform power on
44 LIB_EXPORT int
_plat__Signal_PowerOn(void)45 _plat__Signal_PowerOn(
46     void
47     )
48 {
49     // Reset the timer
50     _plat__TimerReset();
51 
52    // Need to indicate that we lost power
53     s_powerLost = TRUE;
54 
55     return 0;
56 }
57 
58 //*** _plat__WasPowerLost()
59 // Test whether power was lost before a _TPM_Init.
60 //
61 // This function will clear the "hardware" indication of power loss before return.
62 // This means that there can only be one spot in the TPM code where this value
63 // gets read. This method is used here as it is the most difficult to manage in the
64 // TPM code and, if the hardware actually works this way, it is hard to make it
65 // look like anything else. So, the burden is placed on the TPM code rather than the
66 // platform code
67 //  Return Type: int
68 //      TRUE(1)         power was lost
69 //      FALSE(0)        power was not lost
70 LIB_EXPORT int
_plat__WasPowerLost(void)71 _plat__WasPowerLost(
72     void
73     )
74 {
75     int         retVal = s_powerLost;
76     s_powerLost = FALSE;
77     return retVal;
78 }
79 
80 //*** _plat_Signal_Reset()
81 // This a TPM reset without a power loss.
82 LIB_EXPORT int
_plat__Signal_Reset(void)83 _plat__Signal_Reset(
84     void
85     )
86 {
87     // Initialize locality
88     s_locality = 0;
89 
90     // Command cancel
91     s_isCanceled = FALSE;
92 
93     _TPM_Init();
94 
95     // if we are doing reset but did not have a power failure, then we should
96     // not need to reload NV ...
97 
98     return 0;
99 }
100 
101 //***_plat__Signal_PowerOff()
102 // Signal platform power off
103 LIB_EXPORT void
_plat__Signal_PowerOff(void)104 _plat__Signal_PowerOff(
105     void
106     )
107 {
108     // Prepare NV memory for power off
109     _plat__NVDisable(0);
110 
111     // Disable tick ACT tick processing
112     _plat__ACT_EnableTicks(FALSE);
113 
114     return;
115 }