| 1 | /** @file\r |
| 2 | Timer Architecture Protocol driver of the ARM flavor\r |
| 3 | \r |
| 4 | Copyright (c) 2011-2013 ARM Ltd. All rights reserved.<BR>\r |
| 5 | \r |
| 6 | This program and the accompanying materials\r |
| 7 | are licensed and made available under the terms and conditions of the BSD License\r |
| 8 | which accompanies this distribution. The full text of the license may be found at\r |
| 9 | http://opensource.org/licenses/bsd-license.php\r |
| 10 | \r |
| 11 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r |
| 12 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r |
| 13 | \r |
| 14 | **/\r |
| 15 | \r |
| 16 | \r |
| 17 | #include <PiDxe.h>\r |
| 18 | \r |
| 19 | #include <Library/ArmLib.h>\r |
| 20 | #include <Library/BaseLib.h>\r |
| 21 | #include <Library/DebugLib.h>\r |
| 22 | #include <Library/BaseMemoryLib.h>\r |
| 23 | #include <Library/UefiBootServicesTableLib.h>\r |
| 24 | #include <Library/UefiLib.h>\r |
| 25 | #include <Library/PcdLib.h>\r |
| 26 | #include <Library/IoLib.h>\r |
| 27 | #include <Library/ArmGenericTimerCounterLib.h>\r |
| 28 | \r |
| 29 | #include <Protocol/Timer.h>\r |
| 30 | #include <Protocol/HardwareInterrupt.h>\r |
| 31 | \r |
| 32 | // The notification function to call on every timer interrupt.\r |
| 33 | EFI_TIMER_NOTIFY mTimerNotifyFunction = (EFI_TIMER_NOTIFY)NULL;\r |
| 34 | EFI_EVENT EfiExitBootServicesEvent = (EFI_EVENT)NULL;\r |
| 35 | \r |
| 36 | // The current period of the timer interrupt\r |
| 37 | UINT64 mTimerPeriod = 0;\r |
| 38 | // The latest Timer Tick calculated for mTimerPeriod\r |
| 39 | UINT64 mTimerTicks = 0;\r |
| 40 | // Number of elapsed period since the last Timer interrupt\r |
| 41 | UINT64 mElapsedPeriod = 1;\r |
| 42 | \r |
| 43 | // Cached copy of the Hardware Interrupt protocol instance\r |
| 44 | EFI_HARDWARE_INTERRUPT_PROTOCOL *gInterrupt = NULL;\r |
| 45 | \r |
| 46 | /**\r |
| 47 | This function registers the handler NotifyFunction so it is called every time\r |
| 48 | the timer interrupt fires. It also passes the amount of time since the last\r |
| 49 | handler call to the NotifyFunction. If NotifyFunction is NULL, then the\r |
| 50 | handler is unregistered. If the handler is registered, then EFI_SUCCESS is\r |
| 51 | returned. If the CPU does not support registering a timer interrupt handler,\r |
| 52 | then EFI_UNSUPPORTED is returned. If an attempt is made to register a handler\r |
| 53 | when a handler is already registered, then EFI_ALREADY_STARTED is returned.\r |
| 54 | If an attempt is made to unregister a handler when a handler is not registered,\r |
| 55 | then EFI_INVALID_PARAMETER is returned. If an error occurs attempting to\r |
| 56 | register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR\r |
| 57 | is returned.\r |
| 58 | \r |
| 59 | @param This The EFI_TIMER_ARCH_PROTOCOL instance.\r |
| 60 | @param NotifyFunction The function to call when a timer interrupt fires. This\r |
| 61 | function executes at TPL_HIGH_LEVEL. The DXE Core will\r |
| 62 | register a handler for the timer interrupt, so it can know\r |
| 63 | how much time has passed. This information is used to\r |
| 64 | signal timer based events. NULL will unregister the handler.\r |
| 65 | @retval EFI_SUCCESS The timer handler was registered.\r |
| 66 | @retval EFI_UNSUPPORTED The platform does not support timer interrupts.\r |
| 67 | @retval EFI_ALREADY_STARTED NotifyFunction is not NULL, and a handler is already\r |
| 68 | registered.\r |
| 69 | @retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not\r |
| 70 | previously registered.\r |
| 71 | @retval EFI_DEVICE_ERROR The timer handler could not be registered.\r |
| 72 | \r |
| 73 | **/\r |
| 74 | EFI_STATUS\r |
| 75 | EFIAPI\r |
| 76 | TimerDriverRegisterHandler (\r |
| 77 | IN EFI_TIMER_ARCH_PROTOCOL *This,\r |
| 78 | IN EFI_TIMER_NOTIFY NotifyFunction\r |
| 79 | )\r |
| 80 | {\r |
| 81 | if ((NotifyFunction == NULL) && (mTimerNotifyFunction == NULL)) {\r |
| 82 | return EFI_INVALID_PARAMETER;\r |
| 83 | }\r |
| 84 | \r |
| 85 | if ((NotifyFunction != NULL) && (mTimerNotifyFunction != NULL)) {\r |
| 86 | return EFI_ALREADY_STARTED;\r |
| 87 | }\r |
| 88 | \r |
| 89 | mTimerNotifyFunction = NotifyFunction;\r |
| 90 | \r |
| 91 | return EFI_SUCCESS;\r |
| 92 | }\r |
| 93 | \r |
| 94 | /**\r |
| 95 | Disable the timer\r |
| 96 | **/\r |
| 97 | VOID\r |
| 98 | EFIAPI\r |
| 99 | ExitBootServicesEvent (\r |
| 100 | IN EFI_EVENT Event,\r |
| 101 | IN VOID *Context\r |
| 102 | )\r |
| 103 | {\r |
| 104 | ArmGenericTimerDisableTimer ();\r |
| 105 | }\r |
| 106 | \r |
| 107 | /**\r |
| 108 | \r |
| 109 | This function adjusts the period of timer interrupts to the value specified\r |
| 110 | by TimerPeriod. If the timer period is updated, then the selected timer\r |
| 111 | period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If\r |
| 112 | the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.\r |
| 113 | If an error occurs while attempting to update the timer period, then the\r |
| 114 | timer hardware will be put back in its state prior to this call, and\r |
| 115 | EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt\r |
| 116 | is disabled. This is not the same as disabling the CPU's interrupts.\r |
| 117 | Instead, it must either turn off the timer hardware, or it must adjust the\r |
| 118 | interrupt controller so that a CPU interrupt is not generated when the timer\r |
| 119 | interrupt fires.\r |
| 120 | \r |
| 121 | @param This The EFI_TIMER_ARCH_PROTOCOL instance.\r |
| 122 | @param TimerPeriod The rate to program the timer interrupt in 100 nS units. If\r |
| 123 | the timer hardware is not programmable, then EFI_UNSUPPORTED is\r |
| 124 | returned. If the timer is programmable, then the timer period\r |
| 125 | will be rounded up to the nearest timer period that is supported\r |
| 126 | by the timer hardware. If TimerPeriod is set to 0, then the\r |
| 127 | timer interrupts will be disabled.\r |
| 128 | \r |
| 129 | \r |
| 130 | @retval EFI_SUCCESS The timer period was changed.\r |
| 131 | @retval EFI_UNSUPPORTED The platform cannot change the period of the timer interrupt.\r |
| 132 | @retval EFI_DEVICE_ERROR The timer period could not be changed due to a device error.\r |
| 133 | \r |
| 134 | **/\r |
| 135 | EFI_STATUS\r |
| 136 | EFIAPI\r |
| 137 | TimerDriverSetTimerPeriod (\r |
| 138 | IN EFI_TIMER_ARCH_PROTOCOL *This,\r |
| 139 | IN UINT64 TimerPeriod\r |
| 140 | )\r |
| 141 | {\r |
| 142 | UINT64 CounterValue;\r |
| 143 | UINT64 TimerTicks;\r |
| 144 | EFI_TPL OriginalTPL;\r |
| 145 | \r |
| 146 | // Always disable the timer\r |
| 147 | ArmGenericTimerDisableTimer ();\r |
| 148 | \r |
| 149 | if (TimerPeriod != 0) {\r |
| 150 | // mTimerTicks = TimerPeriod in 1ms unit x Frequency.10^-3\r |
| 151 | // = TimerPeriod.10^-4 x Frequency.10^-3\r |
| 152 | // = (TimerPeriod x Frequency) x 10^-7\r |
| 153 | TimerTicks = MultU64x32 (TimerPeriod, ArmGenericTimerGetTimerFreq ());\r |
| 154 | TimerTicks = DivU64x32 (TimerTicks, 10000000U);\r |
| 155 | \r |
| 156 | // Raise TPL to update the mTimerTicks and mTimerPeriod to ensure these values\r |
| 157 | // are coherent in the interrupt handler\r |
| 158 | OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);\r |
| 159 | \r |
| 160 | mTimerTicks = TimerTicks;\r |
| 161 | mTimerPeriod = TimerPeriod;\r |
| 162 | mElapsedPeriod = 1;\r |
| 163 | \r |
| 164 | gBS->RestoreTPL (OriginalTPL);\r |
| 165 | \r |
| 166 | // Get value of the current timer\r |
| 167 | CounterValue = ArmGenericTimerGetSystemCount ();\r |
| 168 | // Set the interrupt in Current Time + mTimerTick\r |
| 169 | ArmGenericTimerSetCompareVal (CounterValue + mTimerTicks);\r |
| 170 | \r |
| 171 | // Enable the timer\r |
| 172 | ArmGenericTimerEnableTimer ();\r |
| 173 | } else {\r |
| 174 | // Save the new timer period\r |
| 175 | mTimerPeriod = TimerPeriod;\r |
| 176 | // Reset the elapsed period\r |
| 177 | mElapsedPeriod = 1;\r |
| 178 | }\r |
| 179 | \r |
| 180 | return EFI_SUCCESS;\r |
| 181 | }\r |
| 182 | \r |
| 183 | /**\r |
| 184 | This function retrieves the period of timer interrupts in 100 ns units,\r |
| 185 | returns that value in TimerPeriod, and returns EFI_SUCCESS. If TimerPeriod\r |
| 186 | is NULL, then EFI_INVALID_PARAMETER is returned. If a TimerPeriod of 0 is\r |
| 187 | returned, then the timer is currently disabled.\r |
| 188 | \r |
| 189 | @param This The EFI_TIMER_ARCH_PROTOCOL instance.\r |
| 190 | @param TimerPeriod A pointer to the timer period to retrieve in 100 ns units. If\r |
| 191 | 0 is returned, then the timer is currently disabled.\r |
| 192 | \r |
| 193 | \r |
| 194 | @retval EFI_SUCCESS The timer period was returned in TimerPeriod.\r |
| 195 | @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.\r |
| 196 | \r |
| 197 | **/\r |
| 198 | EFI_STATUS\r |
| 199 | EFIAPI\r |
| 200 | TimerDriverGetTimerPeriod (\r |
| 201 | IN EFI_TIMER_ARCH_PROTOCOL *This,\r |
| 202 | OUT UINT64 *TimerPeriod\r |
| 203 | )\r |
| 204 | {\r |
| 205 | if (TimerPeriod == NULL) {\r |
| 206 | return EFI_INVALID_PARAMETER;\r |
| 207 | }\r |
| 208 | \r |
| 209 | *TimerPeriod = mTimerPeriod;\r |
| 210 | return EFI_SUCCESS;\r |
| 211 | }\r |
| 212 | \r |
| 213 | /**\r |
| 214 | This function generates a soft timer interrupt. If the platform does not support soft\r |
| 215 | timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.\r |
| 216 | If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()\r |
| 217 | service, then a soft timer interrupt will be generated. If the timer interrupt is\r |
| 218 | enabled when this service is called, then the registered handler will be invoked. The\r |
| 219 | registered handler should not be able to distinguish a hardware-generated timer\r |
| 220 | interrupt from a software-generated timer interrupt.\r |
| 221 | \r |
| 222 | @param This The EFI_TIMER_ARCH_PROTOCOL instance.\r |
| 223 | \r |
| 224 | @retval EFI_SUCCESS The soft timer interrupt was generated.\r |
| 225 | @retval EFI_UNSUPPORTED The platform does not support the generation of soft timer interrupts.\r |
| 226 | \r |
| 227 | **/\r |
| 228 | EFI_STATUS\r |
| 229 | EFIAPI\r |
| 230 | TimerDriverGenerateSoftInterrupt (\r |
| 231 | IN EFI_TIMER_ARCH_PROTOCOL *This\r |
| 232 | )\r |
| 233 | {\r |
| 234 | return EFI_UNSUPPORTED;\r |
| 235 | }\r |
| 236 | \r |
| 237 | /**\r |
| 238 | Interface structure for the Timer Architectural Protocol.\r |
| 239 | \r |
| 240 | @par Protocol Description:\r |
| 241 | This protocol provides the services to initialize a periodic timer\r |
| 242 | interrupt, and to register a handler that is called each time the timer\r |
| 243 | interrupt fires. It may also provide a service to adjust the rate of the\r |
| 244 | periodic timer interrupt. When a timer interrupt occurs, the handler is\r |
| 245 | passed the amount of time that has passed since the previous timer\r |
| 246 | interrupt.\r |
| 247 | \r |
| 248 | @param RegisterHandler\r |
| 249 | Registers a handler that will be called each time the\r |
| 250 | timer interrupt fires. TimerPeriod defines the minimum\r |
| 251 | time between timer interrupts, so TimerPeriod will also\r |
| 252 | be the minimum time between calls to the registered\r |
| 253 | handler.\r |
| 254 | \r |
| 255 | @param SetTimerPeriod\r |
| 256 | Sets the period of the timer interrupt in 100 nS units.\r |
| 257 | This function is optional, and may return EFI_UNSUPPORTED.\r |
| 258 | If this function is supported, then the timer period will\r |
| 259 | be rounded up to the nearest supported timer period.\r |
| 260 | \r |
| 261 | \r |
| 262 | @param GetTimerPeriod\r |
| 263 | Retrieves the period of the timer interrupt in 100 nS units.\r |
| 264 | \r |
| 265 | @param GenerateSoftInterrupt\r |
| 266 | Generates a soft timer interrupt that simulates the firing of\r |
| 267 | the timer interrupt. This service can be used to invoke the registered handler if the timer interrupt has been masked for\r |
| 268 | a period of time.\r |
| 269 | \r |
| 270 | **/\r |
| 271 | EFI_TIMER_ARCH_PROTOCOL gTimer = {\r |
| 272 | TimerDriverRegisterHandler,\r |
| 273 | TimerDriverSetTimerPeriod,\r |
| 274 | TimerDriverGetTimerPeriod,\r |
| 275 | TimerDriverGenerateSoftInterrupt\r |
| 276 | };\r |
| 277 | \r |
| 278 | /**\r |
| 279 | \r |
| 280 | C Interrupt Handler called in the interrupt context when Source interrupt is active.\r |
| 281 | \r |
| 282 | \r |
| 283 | @param Source Source of the interrupt. Hardware routing off a specific platform defines\r |
| 284 | what source means.\r |
| 285 | \r |
| 286 | @param SystemContext Pointer to system register context. Mostly used by debuggers and will\r |
| 287 | update the system context after the return from the interrupt if\r |
| 288 | modified. Don't change these values unless you know what you are doing\r |
| 289 | \r |
| 290 | **/\r |
| 291 | VOID\r |
| 292 | EFIAPI\r |
| 293 | TimerInterruptHandler (\r |
| 294 | IN HARDWARE_INTERRUPT_SOURCE Source,\r |
| 295 | IN EFI_SYSTEM_CONTEXT SystemContext\r |
| 296 | )\r |
| 297 | {\r |
| 298 | EFI_TPL OriginalTPL;\r |
| 299 | UINT64 CurrentValue;\r |
| 300 | UINT64 CompareValue;\r |
| 301 | \r |
| 302 | //\r |
| 303 | // DXE core uses this callback for the EFI timer tick. The DXE core uses locks\r |
| 304 | // that raise to TPL_HIGH and then restore back to current level. Thus we need\r |
| 305 | // to make sure TPL level is set to TPL_HIGH while we are handling the timer tick.\r |
| 306 | //\r |
| 307 | OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);\r |
| 308 | \r |
| 309 | // Signal end of interrupt early to help avoid losing subsequent ticks\r |
| 310 | // from long duration handlers\r |
| 311 | gInterrupt->EndOfInterrupt (gInterrupt, Source);\r |
| 312 | \r |
| 313 | // Check if the timer interrupt is active\r |
| 314 | if ((ArmGenericTimerGetTimerCtrlReg () ) & ARM_ARCH_TIMER_ISTATUS) {\r |
| 315 | \r |
| 316 | if (mTimerNotifyFunction) {\r |
| 317 | mTimerNotifyFunction (mTimerPeriod * mElapsedPeriod);\r |
| 318 | }\r |
| 319 | \r |
| 320 | //\r |
| 321 | // Reload the Timer\r |
| 322 | //\r |
| 323 | \r |
| 324 | // Get current counter value\r |
| 325 | CurrentValue = ArmGenericTimerGetSystemCount ();\r |
| 326 | // Get the counter value to compare with\r |
| 327 | CompareValue = ArmGenericTimerGetCompareVal ();\r |
| 328 | \r |
| 329 | // This loop is needed in case we missed interrupts (eg: case when the interrupt handling\r |
| 330 | // has taken longer than mTickPeriod).\r |
| 331 | // Note: Physical Counter is counting up\r |
| 332 | mElapsedPeriod = 0;\r |
| 333 | do {\r |
| 334 | CompareValue += mTimerTicks;\r |
| 335 | mElapsedPeriod++;\r |
| 336 | } while (CompareValue < CurrentValue);\r |
| 337 | \r |
| 338 | // Set next compare value\r |
| 339 | ArmGenericTimerSetCompareVal (CompareValue);\r |
| 340 | ArmGenericTimerEnableTimer ();\r |
| 341 | ArmInstructionSynchronizationBarrier ();\r |
| 342 | }\r |
| 343 | \r |
| 344 | gBS->RestoreTPL (OriginalTPL);\r |
| 345 | }\r |
| 346 | \r |
| 347 | \r |
| 348 | /**\r |
| 349 | Initialize the state information for the Timer Architectural Protocol and\r |
| 350 | the Timer Debug support protocol that allows the debugger to break into a\r |
| 351 | running program.\r |
| 352 | \r |
| 353 | @param ImageHandle of the loaded driver\r |
| 354 | @param SystemTable Pointer to the System Table\r |
| 355 | \r |
| 356 | @retval EFI_SUCCESS Protocol registered\r |
| 357 | @retval EFI_OUT_OF_RESOURCES Cannot allocate protocol data structure\r |
| 358 | @retval EFI_DEVICE_ERROR Hardware problems\r |
| 359 | \r |
| 360 | **/\r |
| 361 | EFI_STATUS\r |
| 362 | EFIAPI\r |
| 363 | TimerInitialize (\r |
| 364 | IN EFI_HANDLE ImageHandle,\r |
| 365 | IN EFI_SYSTEM_TABLE *SystemTable\r |
| 366 | )\r |
| 367 | {\r |
| 368 | EFI_HANDLE Handle = NULL;\r |
| 369 | EFI_STATUS Status;\r |
| 370 | UINTN TimerCtrlReg;\r |
| 371 | UINT32 TimerHypIntrNum;\r |
| 372 | \r |
| 373 | if (ArmIsArchTimerImplemented () == 0) {\r |
| 374 | DEBUG ((EFI_D_ERROR, "ARM Architectural Timer is not available in the CPU, hence cann't use this Driver \n"));\r |
| 375 | ASSERT (0);\r |
| 376 | }\r |
| 377 | \r |
| 378 | // Find the interrupt controller protocol. ASSERT if not found.\r |
| 379 | Status = gBS->LocateProtocol (&gHardwareInterruptProtocolGuid, NULL, (VOID **)&gInterrupt);\r |
| 380 | ASSERT_EFI_ERROR (Status);\r |
| 381 | \r |
| 382 | // Disable the timer\r |
| 383 | TimerCtrlReg = ArmGenericTimerGetTimerCtrlReg ();\r |
| 384 | TimerCtrlReg |= ARM_ARCH_TIMER_IMASK;\r |
| 385 | TimerCtrlReg &= ~ARM_ARCH_TIMER_ENABLE;\r |
| 386 | ArmGenericTimerSetTimerCtrlReg (TimerCtrlReg);\r |
| 387 | Status = TimerDriverSetTimerPeriod (&gTimer, 0);\r |
| 388 | ASSERT_EFI_ERROR (Status);\r |
| 389 | \r |
| 390 | // Install secure and Non-secure interrupt handlers\r |
| 391 | // Note: Because it is not possible to determine the security state of the\r |
| 392 | // CPU dynamically, we just install interrupt handler for both sec and non-sec\r |
| 393 | // timer PPI\r |
| 394 | Status = gInterrupt->RegisterInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerVirtIntrNum), TimerInterruptHandler);\r |
| 395 | ASSERT_EFI_ERROR (Status);\r |
| 396 | \r |
| 397 | //\r |
| 398 | // The hypervisor timer interrupt may be omitted by implementations that\r |
| 399 | // execute under virtualization.\r |
| 400 | //\r |
| 401 | TimerHypIntrNum = PcdGet32 (PcdArmArchTimerHypIntrNum);\r |
| 402 | if (TimerHypIntrNum != 0) {\r |
| 403 | Status = gInterrupt->RegisterInterruptSource (gInterrupt, TimerHypIntrNum, TimerInterruptHandler);\r |
| 404 | ASSERT_EFI_ERROR (Status);\r |
| 405 | }\r |
| 406 | \r |
| 407 | Status = gInterrupt->RegisterInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerSecIntrNum), TimerInterruptHandler);\r |
| 408 | ASSERT_EFI_ERROR (Status);\r |
| 409 | \r |
| 410 | Status = gInterrupt->RegisterInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerIntrNum), TimerInterruptHandler);\r |
| 411 | ASSERT_EFI_ERROR (Status);\r |
| 412 | \r |
| 413 | // Set up default timer\r |
| 414 | Status = TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod)); // TIMER_DEFAULT_PERIOD\r |
| 415 | ASSERT_EFI_ERROR (Status);\r |
| 416 | \r |
| 417 | // Install the Timer Architectural Protocol onto a new handle\r |
| 418 | Status = gBS->InstallMultipleProtocolInterfaces(\r |
| 419 | &Handle,\r |
| 420 | &gEfiTimerArchProtocolGuid, &gTimer,\r |
| 421 | NULL\r |
| 422 | );\r |
| 423 | ASSERT_EFI_ERROR(Status);\r |
| 424 | \r |
| 425 | // Everything is ready, unmask and enable timer interrupts\r |
| 426 | TimerCtrlReg = ARM_ARCH_TIMER_ENABLE;\r |
| 427 | ArmGenericTimerSetTimerCtrlReg (TimerCtrlReg);\r |
| 428 | \r |
| 429 | // Register for an ExitBootServicesEvent\r |
| 430 | Status = gBS->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_NOTIFY, ExitBootServicesEvent, NULL, &EfiExitBootServicesEvent);\r |
| 431 | ASSERT_EFI_ERROR (Status);\r |
| 432 | \r |
| 433 | return Status;\r |
| 434 | }\r |