projects / mirror_edk2.git / blame
| Commit | Line | Data |
|---|---|---|
| 529a5a86 MK |
1 | /** @file\r |
| 2 | SMM Timer feature support\r | |
| 3 | \r | |
| 4 | Copyright (c) 2009 - 2015, Intel Corporation. All rights reserved.<BR>\r | |
| 0acd8697 | 5 | SPDX-License-Identifier: BSD-2-Clause-Patent\r |
| 529a5a86 MK |
6 | \r |
| 7 | **/\r | |
| 8 | \r | |
| 9 | #include "PiSmmCpuDxeSmm.h"\r | |
| 10 | \r | |
| 11 | UINT64 mTimeoutTicker = 0;\r | |
| 12 | //\r | |
| 13 | // Number of counts in a roll-over cycle of the performance counter.\r | |
| 14 | //\r | |
| 15 | UINT64 mCycle = 0;\r | |
| 16 | //\r | |
| 17 | // Flag to indicate the performance counter is count-up or count-down.\r | |
| 18 | //\r | |
| 19 | BOOLEAN mCountDown;\r | |
| 20 | \r | |
| 21 | /**\r | |
| 22 | Initialize Timer for SMM AP Sync.\r | |
| 23 | \r | |
| 24 | **/\r | |
| 25 | VOID\r | |
| 26 | InitializeSmmTimer (\r | |
| 27 | VOID\r | |
| 28 | )\r | |
| 29 | {\r | |
| 30 | UINT64 TimerFrequency;\r | |
| 31 | UINT64 Start;\r | |
| 32 | UINT64 End;\r | |
| 33 | \r | |
| 34 | TimerFrequency = GetPerformanceCounterProperties (&Start, &End);\r | |
| 35 | mTimeoutTicker = DivU64x32 (\r | |
| 36 | MultU64x64(TimerFrequency, PcdGet64 (PcdCpuSmmApSyncTimeout)),\r | |
| 37 | 1000 * 1000\r | |
| 38 | );\r | |
| 39 | if (End < Start) {\r | |
| 40 | mCountDown = TRUE;\r | |
| 41 | mCycle = Start - End;\r | |
| 42 | } else {\r | |
| 43 | mCountDown = FALSE;\r | |
| 44 | mCycle = End - Start;\r | |
| 45 | }\r | |
| 46 | }\r | |
| 47 | \r | |
| 48 | /**\r | |
| 49 | Start Timer for SMM AP Sync.\r | |
| 50 | \r | |
| 51 | **/\r | |
| 52 | UINT64\r | |
| 53 | EFIAPI\r | |
| 54 | StartSyncTimer (\r | |
| 55 | VOID\r | |
| 56 | )\r | |
| 57 | {\r | |
| 58 | return GetPerformanceCounter ();\r | |
| 59 | }\r | |
| 60 | \r | |
| 61 | \r | |
| 62 | /**\r | |
| 63 | Check if the SMM AP Sync timer is timeout.\r | |
| 64 | \r | |
| 65 | @param Timer The start timer from the begin.\r | |
| 66 | \r | |
| 67 | **/\r | |
| 68 | BOOLEAN\r | |
| 69 | EFIAPI\r | |
| 70 | IsSyncTimerTimeout (\r | |
| 71 | IN UINT64 Timer\r | |
| 72 | )\r | |
| 73 | {\r | |
| 74 | UINT64 CurrentTimer;\r | |
| 75 | UINT64 Delta;\r | |
| 76 | \r | |
| 77 | CurrentTimer = GetPerformanceCounter ();\r | |
| 78 | //\r | |
| 79 | // We need to consider the case that CurrentTimer is equal to Timer\r | |
| 80 | // when some timer runs too slow and CPU runs fast. We think roll over\r | |
| 81 | // condition does not happen on this case.\r | |
| 82 | //\r | |
| 83 | if (mCountDown) {\r | |
| 84 | //\r | |
| 85 | // The performance counter counts down. Check for roll over condition.\r | |
| 86 | //\r | |
| 87 | if (CurrentTimer <= Timer) {\r | |
| 88 | Delta = Timer - CurrentTimer;\r | |
| 89 | } else {\r | |
| 90 | //\r | |
| 91 | // Handle one roll-over.\r | |
| 92 | //\r | |
| 93 | Delta = mCycle - (CurrentTimer - Timer) + 1;\r | |
| 94 | }\r | |
| 95 | } else {\r | |
| 96 | //\r | |
| 97 | // The performance counter counts up. Check for roll over condition.\r | |
| 98 | //\r | |
| 99 | if (CurrentTimer >= Timer) {\r | |
| 100 | Delta = CurrentTimer - Timer;\r | |
| 101 | } else {\r | |
| 102 | //\r | |
| 103 | // Handle one roll-over.\r | |
| 104 | //\r | |
| 105 | Delta = mCycle - (Timer - CurrentTimer) + 1;\r | |
| 106 | }\r | |
| 107 | }\r | |
| 108 | \r | |
| 109 | return (BOOLEAN) (Delta >= mTimeoutTicker);\r | |
| 110 | }\r |