| 1 | /** @file\r |
| 2 | Timer Library functions built upon local APIC on IA32/x64.\r |
| 3 | \r |
| 4 | @bug Should use PCD to retrieve all the constants including index of\r |
| 5 | the IA32_APIC_BASE MSR, the offsets of InitialCount, CorrentCount\r |
| 6 | and DivideConfiguration.\r |
| 7 | \r |
| 8 | Copyright (c) 2006, Intel Corporation<BR>\r |
| 9 | All rights reserved. This program and the accompanying materials\r |
| 10 | are licensed and made available under the terms and conditions of the BSD License\r |
| 11 | which accompanies this distribution. The full text of the license may be found at\r |
| 12 | http://opensource.org/licenses/bsd-license.php\r |
| 13 | \r |
| 14 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r |
| 15 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r |
| 16 | \r |
| 17 | Module Name: IpfTimerLib.c\r |
| 18 | \r |
| 19 | **/\r |
| 20 | \r |
| 21 | \r |
| 22 | \r |
| 23 | \r |
| 24 | /**\r |
| 25 | Performs a delay measured as number of ticks.\r |
| 26 | \r |
| 27 | An internal function to perform a delay measured as number of ticks. It's\r |
| 28 | invoked by MicroSecondDelay() and NanoSecondDelay().\r |
| 29 | \r |
| 30 | @param Delay Number of ticks to delay.\r |
| 31 | \r |
| 32 | **/\r |
| 33 | STATIC\r |
| 34 | VOID\r |
| 35 | InternalIpfDelay (\r |
| 36 | IN INT64 Delay\r |
| 37 | )\r |
| 38 | {\r |
| 39 | INT64 Ticks;\r |
| 40 | \r |
| 41 | //\r |
| 42 | // The target timer count is calculated here\r |
| 43 | //\r |
| 44 | Ticks = IpfReadItc () + Delay;\r |
| 45 | \r |
| 46 | //\r |
| 47 | // Wait until time out\r |
| 48 | // Delay > 2^63 could not be handled by this function\r |
| 49 | // Timer wrap-arounds are handled correctly by this function\r |
| 50 | //\r |
| 51 | while (Ticks - IpfReadItc () >= 0);\r |
| 52 | }\r |
| 53 | \r |
| 54 | /**\r |
| 55 | Stalls the CPU for at least the given number of microseconds.\r |
| 56 | \r |
| 57 | Stalls the CPU for the number of microseconds specified by MicroSeconds.\r |
| 58 | \r |
| 59 | @param MicroSeconds The minimum number of microseconds to delay.\r |
| 60 | \r |
| 61 | @return MicroSeconds\r |
| 62 | \r |
| 63 | **/\r |
| 64 | UINTN\r |
| 65 | EFIAPI\r |
| 66 | MicroSecondDelay (\r |
| 67 | IN UINTN MicroSeconds\r |
| 68 | )\r |
| 69 | {\r |
| 70 | InternalIpfDelay (\r |
| 71 | GetPerformanceCounterProperties (NULL, NULL) *\r |
| 72 | MicroSeconds /\r |
| 73 | 1000000\r |
| 74 | );\r |
| 75 | return MicroSeconds;\r |
| 76 | }\r |
| 77 | \r |
| 78 | /**\r |
| 79 | Stalls the CPU for at least the given number of nanoseconds.\r |
| 80 | \r |
| 81 | Stalls the CPU for the number of nanoseconds specified by NanoSeconds.\r |
| 82 | \r |
| 83 | @param NanoSeconds The minimum number of nanoseconds to delay.\r |
| 84 | \r |
| 85 | @return NanoSeconds\r |
| 86 | \r |
| 87 | **/\r |
| 88 | UINTN\r |
| 89 | EFIAPI\r |
| 90 | NanoSecondDelay (\r |
| 91 | IN UINTN NanoSeconds\r |
| 92 | )\r |
| 93 | {\r |
| 94 | InternalIpfDelay (\r |
| 95 | GetPerformanceCounterProperties (NULL, NULL) *\r |
| 96 | NanoSeconds /\r |
| 97 | 1000000000\r |
| 98 | );\r |
| 99 | return NanoSeconds;\r |
| 100 | }\r |
| 101 | \r |
| 102 | /**\r |
| 103 | Retrieves the current value of a 64-bit free running performance counter.\r |
| 104 | \r |
| 105 | Retrieves the current value of a 64-bit free running performance counter. The\r |
| 106 | counter can either count up by 1 or count down by 1. If the physical\r |
| 107 | performance counter counts by a larger increment, then the counter values\r |
| 108 | must be translated. The properties of the counter can be retrieved from\r |
| 109 | GetPerformanceCounterProperties().\r |
| 110 | \r |
| 111 | @return The current value of the free running performance counter.\r |
| 112 | \r |
| 113 | **/\r |
| 114 | UINT64\r |
| 115 | EFIAPI\r |
| 116 | GetPerformanceCounter (\r |
| 117 | VOID\r |
| 118 | )\r |
| 119 | {\r |
| 120 | return IpfReadItc ();\r |
| 121 | }\r |
| 122 | \r |
| 123 | /**\r |
| 124 | Retrieves the 64-bit frequency in Hz and the range of performance counter\r |
| 125 | values.\r |
| 126 | \r |
| 127 | If StartValue is not NULL, then the value that the performance counter starts\r |
| 128 | with immediately after is it rolls over is returned in StartValue. If\r |
| 129 | EndValue is not NULL, then the value that the performance counter end with\r |
| 130 | immediately before it rolls over is returned in EndValue. The 64-bit\r |
| 131 | frequency of the performance counter in Hz is always returned. If StartValue\r |
| 132 | is less than EndValue, then the performance counter counts up. If StartValue\r |
| 133 | is greater than EndValue, then the performance counter counts down. For\r |
| 134 | example, a 64-bit free running counter that counts up would have a StartValue\r |
| 135 | of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter\r |
| 136 | that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.\r |
| 137 | \r |
| 138 | @param StartValue The value the performance counter starts with when it\r |
| 139 | rolls over.\r |
| 140 | @param EndValue The value that the performance counter ends with before\r |
| 141 | it rolls over.\r |
| 142 | \r |
| 143 | @return The frequency in Hz.\r |
| 144 | \r |
| 145 | **/\r |
| 146 | UINT64\r |
| 147 | EFIAPI\r |
| 148 | GetPerformanceCounterProperties (\r |
| 149 | OUT UINT64 *StartValue, OPTIONAL\r |
| 150 | OUT UINT64 *EndValue OPTIONAL\r |
| 151 | )\r |
| 152 | {\r |
| 153 | PAL_PROC_RETURN PalRet;\r |
| 154 | UINT64 BaseFrequence;\r |
| 155 | \r |
| 156 | PalRet = PalCallStatic (NULL, 13, 0, 0, 0);\r |
| 157 | ASSERT (PalRet.Status == 0);\r |
| 158 | BaseFrequence = PalRet.r9;\r |
| 159 | \r |
| 160 | PalRet = PalCallStatic (NULL, 14, 0, 0, 0);\r |
| 161 | ASSERT (PalRet.Status == 0);\r |
| 162 | \r |
| 163 | if (StartValue != NULL) {\r |
| 164 | *StartValue = 0;\r |
| 165 | }\r |
| 166 | \r |
| 167 | if (EndValue != NULL) {\r |
| 168 | *EndValue = (UINT64)(-1);\r |
| 169 | }\r |
| 170 | \r |
| 171 | return BaseFrequence * (PalRet.r11 >> 32) / (UINT32)PalRet.r11;\r |
| 172 | }\r |