| 1 | /** @file\r |
| 2 | Timer Library functions for EBC.\r |
| 3 | \r |
| 4 | Copyright (c) 2006, Intel Corporation<BR>\r |
| 5 | All rights reserved. This program and the accompanying materials\r |
| 6 | are licensed and made available under the terms and conditions of the BSD License\r |
| 7 | which accompanies this distribution. The full text of the license may be found at\r |
| 8 | http://opensource.org/licenses/bsd-license.php\r |
| 9 | \r |
| 10 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r |
| 11 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r |
| 12 | \r |
| 13 | Module Name: EbcTimerLib.c\r |
| 14 | \r |
| 15 | **/\r |
| 16 | \r |
| 17 | /**\r |
| 18 | Stalls the CPU for at least the given number of microseconds.\r |
| 19 | \r |
| 20 | Stalls the CPU for the number of microseconds specified by MicroSeconds.\r |
| 21 | \r |
| 22 | @param MicroSeconds The minimum number of microseconds to delay.\r |
| 23 | \r |
| 24 | @return Return value depends on implementation.\r |
| 25 | \r |
| 26 | **/\r |
| 27 | UINTN\r |
| 28 | EFIAPI\r |
| 29 | MicroSecondDelay (\r |
| 30 | IN UINTN MicroSeconds\r |
| 31 | )\r |
| 32 | {\r |
| 33 | //\r |
| 34 | // EBC architecture does not support local APIC timer.\r |
| 35 | //\r |
| 36 | ASSERT (FALSE);\r |
| 37 | return 0;\r |
| 38 | }\r |
| 39 | \r |
| 40 | /**\r |
| 41 | Stalls the CPU for at least the given number of nanoseconds.\r |
| 42 | \r |
| 43 | Stalls the CPU for the number of nanoseconds specified by NanoSeconds.\r |
| 44 | \r |
| 45 | @param NanoSeconds The minimum number of nanoseconds to delay.\r |
| 46 | \r |
| 47 | @return Return value depends on implementation.\r |
| 48 | \r |
| 49 | **/\r |
| 50 | UINTN\r |
| 51 | EFIAPI\r |
| 52 | NanoSecondDelay (\r |
| 53 | IN UINTN NanoSeconds\r |
| 54 | )\r |
| 55 | {\r |
| 56 | //\r |
| 57 | // EBC architecture does not support local APIC timer.\r |
| 58 | //\r |
| 59 | ASSERT (FALSE);\r |
| 60 | return 0;\r |
| 61 | }\r |
| 62 | \r |
| 63 | /**\r |
| 64 | Retrieves the current value of a 64-bit free running performance counter.\r |
| 65 | \r |
| 66 | Retrieves the current value of a 64-bit free running performance counter. The\r |
| 67 | counter can either count up by 1 or count down by 1. If the physical\r |
| 68 | performance counter counts by a larger increment, then the counter values\r |
| 69 | must be translated. The properties of the counter can be retrieved from\r |
| 70 | GetPerformanceCounterProperties().\r |
| 71 | \r |
| 72 | @return The current value of the free running performance counter.\r |
| 73 | \r |
| 74 | **/\r |
| 75 | UINT64\r |
| 76 | EFIAPI\r |
| 77 | GetPerformanceCounter (\r |
| 78 | VOID\r |
| 79 | )\r |
| 80 | {\r |
| 81 | //\r |
| 82 | // EBC architecture does not support local APIC timer.\r |
| 83 | //\r |
| 84 | ASSERT (FALSE);\r |
| 85 | return 0;\r |
| 86 | }\r |
| 87 | \r |
| 88 | /**\r |
| 89 | Retrieves the 64-bit frequency in Hz and the range of performance counter\r |
| 90 | values.\r |
| 91 | \r |
| 92 | If StartValue is not NULL, then the value that the performance counter starts\r |
| 93 | with immediately after is it rolls over is returned in StartValue. If\r |
| 94 | EndValue is not NULL, then the value that the performance counter end with\r |
| 95 | immediately before it rolls over is returned in EndValue. The 64-bit\r |
| 96 | frequency of the performance counter in Hz is always returned. If StartValue\r |
| 97 | is less than EndValue, then the performance counter counts up. If StartValue\r |
| 98 | is greater than EndValue, then the performance counter counts down. For\r |
| 99 | example, a 64-bit free running counter that counts up would have a StartValue\r |
| 100 | of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter\r |
| 101 | that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.\r |
| 102 | \r |
| 103 | @param StartValue The value the performance counter starts with when it\r |
| 104 | rolls over.\r |
| 105 | @param EndValue The value that the performance counter ends with before\r |
| 106 | it rolls over.\r |
| 107 | \r |
| 108 | @return The frequency in Hz.\r |
| 109 | \r |
| 110 | **/\r |
| 111 | UINT64\r |
| 112 | EFIAPI\r |
| 113 | GetPerformanceCounterProperties (\r |
| 114 | IN UINT64 *StartValue,\r |
| 115 | IN UINT64 *EndValue\r |
| 116 | )\r |
| 117 | {\r |
| 118 | //\r |
| 119 | // EBC architecture does not support local APIC timer.\r |
| 120 | //\r |
| 121 | ASSERT (FALSE);\r |
| 122 | return 0; \r |
| 123 | }\r |