1 /** @file 2 A non-functional instance of the Timer Library. 3 4 Copyright (c) 2007 - 2010, Intel Corporation. All rights reserved.<BR> 5 This program and the accompanying materials 6 are licensed and made available under the terms and conditions of the BSD License 7 which accompanies this distribution. The full text of the license may be found at 8 http://opensource.org/licenses/bsd-license.php. 9 10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 12 13 **/ 14 15 #include <PiPei.h> 16 #include <Library/BaseLib.h> 17 #include <Library/TimerLib.h> 18 #include <Library/DebugLib.h> 19 #include <Library/EmuThunkLib.h> 20 #include <Library/UefiBootServicesTableLib.h> 21 #include <Library/UefiLib.h> 22 23 #include <Protocol/Timer.h> 24 25 26 STATIC UINT64 gTimerPeriod = 0; 27 STATIC EFI_TIMER_ARCH_PROTOCOL *gTimerAp = NULL; 28 STATIC EFI_EVENT gTimerEvent = NULL; 29 STATIC VOID *gRegistration = NULL; 30 31 VOID 32 EFIAPI 33 RegisterTimerArchProtocol ( 34 IN EFI_EVENT Event, 35 IN VOID *Context 36 ) 37 { 38 EFI_STATUS Status; 39 40 Status = gBS->LocateProtocol (&gEfiTimerArchProtocolGuid, NULL, (VOID **)&gTimerAp); 41 if (!EFI_ERROR (Status)) { 42 Status = gTimerAp->GetTimerPeriod (gTimerAp, &gTimerPeriod); 43 ASSERT_EFI_ERROR (Status); 44 45 // Convert to Nanoseconds. 46 gTimerPeriod = MultU64x32 (gTimerPeriod, 100); 47 48 if (gTimerEvent == NULL) { 49 Status = gBS->CreateEvent (EVT_TIMER, 0, NULL, NULL, (VOID **)&gTimerEvent); 50 ASSERT_EFI_ERROR (Status); 51 } 52 } 53 } 54 55 56 57 /** 58 Stalls the CPU for at least the given number of microseconds. 59 60 Stalls the CPU for the number of microseconds specified by MicroSeconds. 61 62 @param MicroSeconds The minimum number of microseconds to delay. 63 64 @return The value of MicroSeconds inputted. 65 66 **/ 67 UINTN 68 EFIAPI 69 MicroSecondDelay ( 70 IN UINTN MicroSeconds 71 ) 72 { 73 return NanoSecondDelay (MicroSeconds * 1000); 74 } 75 76 77 /** 78 Stalls the CPU for at least the given number of nanoseconds. 79 80 Stalls the CPU for the number of nanoseconds specified by NanoSeconds. 81 82 @param NanoSeconds The minimum number of nanoseconds to delay. 83 84 @return The value of NanoSeconds inputted. 85 86 **/ 87 UINTN 88 EFIAPI 89 NanoSecondDelay ( 90 IN UINTN NanoSeconds 91 ) 92 { 93 EFI_STATUS Status; 94 UINT64 HundredNanoseconds; 95 UINTN Index; 96 97 if ((gTimerPeriod != 0) && 98 ((UINT64)NanoSeconds > gTimerPeriod) && 99 (EfiGetCurrentTpl () == TPL_APPLICATION)) { 100 // 101 // This stall is long, so use gBS->WaitForEvent () to yield CPU to DXE Core 102 // 103 104 HundredNanoseconds = DivU64x32 (NanoSeconds, 100); 105 Status = gBS->SetTimer (gTimerEvent, TimerRelative, HundredNanoseconds); 106 ASSERT_EFI_ERROR (Status); 107 108 Status = gBS->WaitForEvent (sizeof (gTimerEvent)/sizeof (EFI_EVENT), &gTimerEvent, &Index); 109 ASSERT_EFI_ERROR (Status); 110 111 } else { 112 gEmuThunk->Sleep (NanoSeconds); 113 } 114 return NanoSeconds; 115 } 116 117 118 /** 119 Retrieves the current value of a 64-bit free running performance counter. 120 121 The counter can either count up by 1 or count down by 1. If the physical 122 performance counter counts by a larger increment, then the counter values 123 must be translated. The properties of the counter can be retrieved from 124 GetPerformanceCounterProperties(). 125 126 @return The current value of the free running performance counter. 127 128 **/ 129 UINT64 130 EFIAPI 131 GetPerformanceCounter ( 132 VOID 133 ) 134 { 135 return gEmuThunk->QueryPerformanceCounter (); 136 } 137 138 /** 139 Retrieves the 64-bit frequency in Hz and the range of performance counter 140 values. 141 142 If StartValue is not NULL, then the value that the performance counter starts 143 with immediately after is it rolls over is returned in StartValue. If 144 EndValue is not NULL, then the value that the performance counter end with 145 immediately before it rolls over is returned in EndValue. The 64-bit 146 frequency of the performance counter in Hz is always returned. If StartValue 147 is less than EndValue, then the performance counter counts up. If StartValue 148 is greater than EndValue, then the performance counter counts down. For 149 example, a 64-bit free running counter that counts up would have a StartValue 150 of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter 151 that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0. 152 153 @param StartValue The value the performance counter starts with when it 154 rolls over. 155 @param EndValue The value that the performance counter ends with before 156 it rolls over. 157 158 @return The frequency in Hz. 159 160 **/ 161 UINT64 162 EFIAPI 163 GetPerformanceCounterProperties ( 164 OUT UINT64 *StartValue, OPTIONAL 165 OUT UINT64 *EndValue OPTIONAL 166 ) 167 { 168 169 if (StartValue != NULL) { 170 *StartValue = 0ULL; 171 } 172 if (EndValue != NULL) { 173 *EndValue = (UINT64)-1LL; 174 } 175 176 return gEmuThunk->QueryPerformanceFrequency (); 177 } 178 179 180 /** 181 Register for the Timer AP protocol. 182 183 @param ImageHandle The firmware allocated handle for the EFI image. 184 @param SystemTable A pointer to the EFI System Table. 185 186 @retval EFI_SUCCESS The constructor always returns EFI_SUCCESS. 187 188 **/ 189 EFI_STATUS 190 EFIAPI 191 DxeTimerLibConstructor ( 192 IN EFI_HANDLE ImageHandle, 193 IN EFI_SYSTEM_TABLE *SystemTable 194 ) 195 { 196 EfiCreateProtocolNotifyEvent ( 197 &gEfiTimerArchProtocolGuid, 198 TPL_CALLBACK, 199 RegisterTimerArchProtocol, 200 NULL, 201 &gRegistration 202 ); 203 204 return EFI_SUCCESS; 205 } 206 207
