| 1 | /*++ @file\r |
| 2 | Emu Emulation Timer Architectural Protocol Driver as defined in DXE CIS\r |
| 3 | \r |
| 4 | This Timer module uses an Emu Thread to simulate the timer-tick driven\r |
| 5 | timer service. In the future, the Thread creation should possibly be\r |
| 6 | abstracted by the CPU architectural protocol\r |
| 7 | \r |
| 8 | Copyright (c) 2004, Intel Corporation. All rights reserved.<BR>\r |
| 9 | Portions copyright (c) 2010 - 2011, Apple Inc. All rights reserved.\r |
| 10 | This program and the accompanying materials\r |
| 11 | are licensed and made available under the terms and conditions of the BSD License\r |
| 12 | which accompanies this distribution. The full text of the license may be found at\r |
| 13 | http://opensource.org/licenses/bsd-license.php\r |
| 14 | \r |
| 15 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r |
| 16 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r |
| 17 | \r |
| 18 | \r |
| 19 | **/\r |
| 20 | \r |
| 21 | #include "PiDxe.h"\r |
| 22 | #include <Protocol/Timer.h>\r |
| 23 | #include <Protocol/Cpu.h>\r |
| 24 | #include "Timer.h"\r |
| 25 | #include <Library/BaseLib.h>\r |
| 26 | #include <Library/DebugLib.h>\r |
| 27 | #include <Library/UefiLib.h>\r |
| 28 | #include <Library/UefiDriverEntryPoint.h>\r |
| 29 | #include <Library/MemoryAllocationLib.h>\r |
| 30 | #include <Library/UefiBootServicesTableLib.h>\r |
| 31 | #include <Library/EmuThunkLib.h>\r |
| 32 | \r |
| 33 | //\r |
| 34 | // Pointer to the CPU Architectural Protocol instance\r |
| 35 | //\r |
| 36 | EFI_CPU_ARCH_PROTOCOL *mCpu;\r |
| 37 | \r |
| 38 | //\r |
| 39 | // The Timer Architectural Protocol that this driver produces\r |
| 40 | //\r |
| 41 | EFI_TIMER_ARCH_PROTOCOL mTimer = {\r |
| 42 | EmuTimerDriverRegisterHandler,\r |
| 43 | EmuTimerDriverSetTimerPeriod,\r |
| 44 | EmuTimerDriverGetTimerPeriod,\r |
| 45 | EmuTimerDriverGenerateSoftInterrupt\r |
| 46 | };\r |
| 47 | \r |
| 48 | //\r |
| 49 | // The notification function to call on every timer interrupt\r |
| 50 | //\r |
| 51 | EFI_TIMER_NOTIFY mTimerNotifyFunction = NULL;\r |
| 52 | \r |
| 53 | //\r |
| 54 | // The current period of the timer interrupt\r |
| 55 | //\r |
| 56 | UINT64 mTimerPeriodMs;\r |
| 57 | \r |
| 58 | \r |
| 59 | VOID\r |
| 60 | EFIAPI\r |
| 61 | TimerCallback (UINT64 DeltaMs)\r |
| 62 | {\r |
| 63 | EFI_TPL OriginalTPL;\r |
| 64 | EFI_TIMER_NOTIFY CallbackFunction;\r |
| 65 | \r |
| 66 | \r |
| 67 | OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);\r |
| 68 | \r |
| 69 | if (OriginalTPL < TPL_HIGH_LEVEL) {\r |
| 70 | CallbackFunction = mTimerNotifyFunction;\r |
| 71 | \r |
| 72 | //\r |
| 73 | // Only invoke the callback function if a Non-NULL handler has been\r |
| 74 | // registered. Assume all other handlers are legal.\r |
| 75 | //\r |
| 76 | if (CallbackFunction != NULL) {\r |
| 77 | CallbackFunction ((UINT64) (DeltaMs * 10000));\r |
| 78 | }\r |
| 79 | }\r |
| 80 | \r |
| 81 | gBS->RestoreTPL (OriginalTPL);\r |
| 82 | \r |
| 83 | }\r |
| 84 | \r |
| 85 | EFI_STATUS\r |
| 86 | EFIAPI\r |
| 87 | EmuTimerDriverRegisterHandler (\r |
| 88 | IN EFI_TIMER_ARCH_PROTOCOL *This,\r |
| 89 | IN EFI_TIMER_NOTIFY NotifyFunction\r |
| 90 | )\r |
| 91 | /*++\r |
| 92 | \r |
| 93 | Routine Description:\r |
| 94 | \r |
| 95 | This function registers the handler NotifyFunction so it is called every time\r |
| 96 | the timer interrupt fires. It also passes the amount of time since the last\r |
| 97 | handler call to the NotifyFunction. If NotifyFunction is NULL, then the\r |
| 98 | handler is unregistered. If the handler is registered, then EFI_SUCCESS is\r |
| 99 | returned. If the CPU does not support registering a timer interrupt handler,\r |
| 100 | then EFI_UNSUPPORTED is returned. If an attempt is made to register a handler\r |
| 101 | when a handler is already registered, then EFI_ALREADY_STARTED is returned.\r |
| 102 | If an attempt is made to unregister a handler when a handler is not registered,\r |
| 103 | then EFI_INVALID_PARAMETER is returned. If an error occurs attempting to\r |
| 104 | register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR\r |
| 105 | is returned.\r |
| 106 | \r |
| 107 | Arguments:\r |
| 108 | \r |
| 109 | This - The EFI_TIMER_ARCH_PROTOCOL instance.\r |
| 110 | \r |
| 111 | NotifyFunction - The function to call when a timer interrupt fires. This\r |
| 112 | function executes at TPL_HIGH_LEVEL. The DXE Core will\r |
| 113 | register a handler for the timer interrupt, so it can know\r |
| 114 | how much time has passed. This information is used to\r |
| 115 | signal timer based events. NULL will unregister the handler.\r |
| 116 | \r |
| 117 | Returns:\r |
| 118 | \r |
| 119 | EFI_SUCCESS - The timer handler was registered.\r |
| 120 | \r |
| 121 | EFI_UNSUPPORTED - The platform does not support timer interrupts.\r |
| 122 | \r |
| 123 | EFI_ALREADY_STARTED - NotifyFunction is not NULL, and a handler is already\r |
| 124 | registered.\r |
| 125 | \r |
| 126 | EFI_INVALID_PARAMETER - NotifyFunction is NULL, and a handler was not\r |
| 127 | previously registered.\r |
| 128 | \r |
| 129 | EFI_DEVICE_ERROR - The timer handler could not be registered.\r |
| 130 | \r |
| 131 | **/\r |
| 132 | {\r |
| 133 | //\r |
| 134 | // Check for invalid parameters\r |
| 135 | //\r |
| 136 | if (NotifyFunction == NULL && mTimerNotifyFunction == NULL) {\r |
| 137 | return EFI_INVALID_PARAMETER;\r |
| 138 | }\r |
| 139 | \r |
| 140 | if (NotifyFunction != NULL && mTimerNotifyFunction != NULL) {\r |
| 141 | return EFI_ALREADY_STARTED;\r |
| 142 | }\r |
| 143 | \r |
| 144 | if (NotifyFunction == NULL) {\r |
| 145 | /* Disable timer. */\r |
| 146 | gEmuThunk->SetTimer (0, TimerCallback);\r |
| 147 | } else if (mTimerNotifyFunction == NULL) {\r |
| 148 | /* Enable Timer. */\r |
| 149 | gEmuThunk->SetTimer (mTimerPeriodMs, TimerCallback);\r |
| 150 | }\r |
| 151 | mTimerNotifyFunction = NotifyFunction;\r |
| 152 | \r |
| 153 | return EFI_SUCCESS;\r |
| 154 | }\r |
| 155 | \r |
| 156 | EFI_STATUS\r |
| 157 | EFIAPI\r |
| 158 | EmuTimerDriverSetTimerPeriod (\r |
| 159 | IN EFI_TIMER_ARCH_PROTOCOL *This,\r |
| 160 | IN UINT64 TimerPeriod\r |
| 161 | )\r |
| 162 | /*++\r |
| 163 | \r |
| 164 | Routine Description:\r |
| 165 | \r |
| 166 | This function adjusts the period of timer interrupts to the value specified\r |
| 167 | by TimerPeriod. If the timer period is updated, then the selected timer\r |
| 168 | period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If\r |
| 169 | the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.\r |
| 170 | If an error occurs while attempting to update the timer period, then the\r |
| 171 | timer hardware will be put back in its state prior to this call, and\r |
| 172 | EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt\r |
| 173 | is disabled. This is not the same as disabling the CPU's interrupts.\r |
| 174 | Instead, it must either turn off the timer hardware, or it must adjust the\r |
| 175 | interrupt controller so that a CPU interrupt is not generated when the timer\r |
| 176 | interrupt fires.\r |
| 177 | \r |
| 178 | Arguments:\r |
| 179 | \r |
| 180 | This - The EFI_TIMER_ARCH_PROTOCOL instance.\r |
| 181 | \r |
| 182 | TimerPeriod - The rate to program the timer interrupt in 100 nS units. If\r |
| 183 | the timer hardware is not programmable, then EFI_UNSUPPORTED is\r |
| 184 | returned. If the timer is programmable, then the timer period\r |
| 185 | will be rounded up to the nearest timer period that is supported\r |
| 186 | by the timer hardware. If TimerPeriod is set to 0, then the\r |
| 187 | timer interrupts will be disabled.\r |
| 188 | \r |
| 189 | Returns:\r |
| 190 | \r |
| 191 | EFI_SUCCESS - The timer period was changed.\r |
| 192 | \r |
| 193 | EFI_UNSUPPORTED - The platform cannot change the period of the timer interrupt.\r |
| 194 | \r |
| 195 | EFI_DEVICE_ERROR - The timer period could not be changed due to a device error.\r |
| 196 | \r |
| 197 | **/\r |
| 198 | {\r |
| 199 | \r |
| 200 | //\r |
| 201 | // If TimerPeriod is 0, then the timer thread should be canceled\r |
| 202 | // If the TimerPeriod is valid, then create and/or adjust the period of the timer thread\r |
| 203 | //\r |
| 204 | if (TimerPeriod == 0\r |
| 205 | || ((TimerPeriod > TIMER_MINIMUM_VALUE)\r |
| 206 | && (TimerPeriod < TIMER_MAXIMUM_VALUE))) {\r |
| 207 | mTimerPeriodMs = DivU64x32 (TimerPeriod + 5000, 10000);\r |
| 208 | \r |
| 209 | gEmuThunk->SetTimer (mTimerPeriodMs, TimerCallback);\r |
| 210 | }\r |
| 211 | \r |
| 212 | return EFI_SUCCESS;\r |
| 213 | }\r |
| 214 | \r |
| 215 | EFI_STATUS\r |
| 216 | EFIAPI\r |
| 217 | EmuTimerDriverGetTimerPeriod (\r |
| 218 | IN EFI_TIMER_ARCH_PROTOCOL *This,\r |
| 219 | OUT UINT64 *TimerPeriod\r |
| 220 | )\r |
| 221 | /*++\r |
| 222 | \r |
| 223 | Routine Description:\r |
| 224 | \r |
| 225 | This function retrieves the period of timer interrupts in 100 ns units,\r |
| 226 | returns that value in TimerPeriod, and returns EFI_SUCCESS. If TimerPeriod\r |
| 227 | is NULL, then EFI_INVALID_PARAMETER is returned. If a TimerPeriod of 0 is\r |
| 228 | returned, then the timer is currently disabled.\r |
| 229 | \r |
| 230 | Arguments:\r |
| 231 | \r |
| 232 | This - The EFI_TIMER_ARCH_PROTOCOL instance.\r |
| 233 | \r |
| 234 | TimerPeriod - A pointer to the timer period to retrieve in 100 ns units. If\r |
| 235 | 0 is returned, then the timer is currently disabled.\r |
| 236 | \r |
| 237 | Returns:\r |
| 238 | \r |
| 239 | EFI_SUCCESS - The timer period was returned in TimerPeriod.\r |
| 240 | \r |
| 241 | EFI_INVALID_PARAMETER - TimerPeriod is NULL.\r |
| 242 | \r |
| 243 | **/\r |
| 244 | {\r |
| 245 | if (TimerPeriod == NULL) {\r |
| 246 | return EFI_INVALID_PARAMETER;\r |
| 247 | }\r |
| 248 | \r |
| 249 | *TimerPeriod = mTimerPeriodMs * 10000;\r |
| 250 | \r |
| 251 | return EFI_SUCCESS;\r |
| 252 | }\r |
| 253 | \r |
| 254 | EFI_STATUS\r |
| 255 | EFIAPI\r |
| 256 | EmuTimerDriverGenerateSoftInterrupt (\r |
| 257 | IN EFI_TIMER_ARCH_PROTOCOL *This\r |
| 258 | )\r |
| 259 | /*++\r |
| 260 | \r |
| 261 | Routine Description:\r |
| 262 | \r |
| 263 | This function generates a soft timer interrupt. If the platform does not support soft\r |
| 264 | timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.\r |
| 265 | If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()\r |
| 266 | service, then a soft timer interrupt will be generated. If the timer interrupt is\r |
| 267 | enabled when this service is called, then the registered handler will be invoked. The\r |
| 268 | registered handler should not be able to distinguish a hardware-generated timer\r |
| 269 | interrupt from a software-generated timer interrupt.\r |
| 270 | \r |
| 271 | Arguments:\r |
| 272 | \r |
| 273 | This - The EFI_TIMER_ARCH_PROTOCOL instance.\r |
| 274 | \r |
| 275 | Returns:\r |
| 276 | \r |
| 277 | EFI_SUCCESS - The soft timer interrupt was generated.\r |
| 278 | \r |
| 279 | EFI_UNSUPPORTEDT - The platform does not support the generation of soft timer interrupts.\r |
| 280 | \r |
| 281 | **/\r |
| 282 | {\r |
| 283 | return EFI_UNSUPPORTED;\r |
| 284 | }\r |
| 285 | \r |
| 286 | EFI_STATUS\r |
| 287 | EFIAPI\r |
| 288 | EmuTimerDriverInitialize (\r |
| 289 | IN EFI_HANDLE ImageHandle,\r |
| 290 | IN EFI_SYSTEM_TABLE *SystemTable\r |
| 291 | )\r |
| 292 | /*++\r |
| 293 | \r |
| 294 | Routine Description:\r |
| 295 | \r |
| 296 | Initialize the Timer Architectural Protocol driver\r |
| 297 | \r |
| 298 | Arguments:\r |
| 299 | \r |
| 300 | ImageHandle - ImageHandle of the loaded driver\r |
| 301 | \r |
| 302 | SystemTable - Pointer to the System Table\r |
| 303 | \r |
| 304 | Returns:\r |
| 305 | \r |
| 306 | EFI_SUCCESS - Timer Architectural Protocol created\r |
| 307 | \r |
| 308 | EFI_OUT_OF_RESOURCES - Not enough resources available to initialize driver.\r |
| 309 | \r |
| 310 | EFI_DEVICE_ERROR - A device error occured attempting to initialize the driver.\r |
| 311 | \r |
| 312 | **/\r |
| 313 | {\r |
| 314 | EFI_STATUS Status;\r |
| 315 | EFI_HANDLE Handle;\r |
| 316 | \r |
| 317 | //\r |
| 318 | // Make sure the Timer Architectural Protocol is not already installed in the system\r |
| 319 | //\r |
| 320 | ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gEfiTimerArchProtocolGuid);\r |
| 321 | \r |
| 322 | //\r |
| 323 | // Get the CPU Architectural Protocol instance\r |
| 324 | //\r |
| 325 | Status = gBS->LocateProtocol (&gEfiCpuArchProtocolGuid, NULL, (void *)&mCpu);\r |
| 326 | ASSERT_EFI_ERROR (Status);\r |
| 327 | \r |
| 328 | //\r |
| 329 | // Install the Timer Architectural Protocol onto a new handle\r |
| 330 | //\r |
| 331 | Handle = NULL;\r |
| 332 | Status = gBS->InstallProtocolInterface (\r |
| 333 | &Handle,\r |
| 334 | &gEfiTimerArchProtocolGuid,\r |
| 335 | EFI_NATIVE_INTERFACE,\r |
| 336 | &mTimer\r |
| 337 | );\r |
| 338 | if (EFI_ERROR (Status)) {\r |
| 339 | return Status;\r |
| 340 | }\r |
| 341 | \r |
| 342 | //\r |
| 343 | // Start the timer thread at the default timer period\r |
| 344 | //\r |
| 345 | Status = mTimer.SetTimerPeriod (&mTimer, DEFAULT_TIMER_TICK_DURATION);\r |
| 346 | if (EFI_ERROR (Status)) {\r |
| 347 | return Status;\r |
| 348 | }\r |
| 349 | \r |
| 350 | return EFI_SUCCESS;\r |
| 351 | }\r |