ArmPlatformPkg/Drivers/SP804TimerDxe/SP804Timer.c

   1 /** @file
   2   Template for Timer Architecture Protocol driver of the ARM flavor
   3
   4   Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
   5
   6   This program and the accompanying materials
   7   are licensed and made available under the terms and conditions of the BSD License
   8   which accompanies this distribution.  The full text of the license may be found at
   9   http://opensource.org/licenses/bsd-license.php
  10
  11   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  12   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  13
  14 **/
  15
  16
  17 #include <PiDxe.h>
  18
  19 #include <Library/BaseLib.h>
  20 #include <Library/DebugLib.h>
  21 #include <Library/BaseMemoryLib.h>
  22 #include <Library/UefiBootServicesTableLib.h>
  23 #include <Library/UefiLib.h>
  24 #include <Library/PcdLib.h>
  25 #include <Library/IoLib.h>
  26
  27 #include <Protocol/Timer.h>
  28 #include <Protocol/HardwareInterrupt.h>
  29
  30 #include <Drivers/SP804Timer.h>
  31
  32 #define SP804_TIMER_PERIODIC_BASE     (UINTN)PcdGet32 (PcdSP804TimerPeriodicBase)
  33 #define SP804_TIMER_METRONOME_BASE    (UINTN)PcdGet32 (PcdSP804TimerMetronomeBase)
  34 #define SP804_TIMER_PERFORMANCE_BASE  (UINTN)PcdGet32 (PcdSP804TimerPerformanceBase)
  35
  36 // The notification function to call on every timer interrupt.
  37 volatile EFI_TIMER_NOTIFY      mTimerNotifyFunction   = (EFI_TIMER_NOTIFY)NULL;
  38 EFI_EVENT                       EfiExitBootServicesEvent        = (EFI_EVENT)NULL;
  39
  40 // The current period of the timer interrupt
  41 volatile UINT64 mTimerPeriod = 0;
  42
  43 // Cached copy of the Hardware Interrupt protocol instance
  44 EFI_HARDWARE_INTERRUPT_PROTOCOL *gInterrupt = NULL;
  45
  46 // Cached interrupt vector
  47 UINTN  gVector;
  48
  49
  50 /**
  51
  52   C Interrupt Handler called in the interrupt context when Source interrupt is active.
  53
  54
  55   @param Source         Source of the interrupt. Hardware routing off a specific platform defines
  56                         what source means.
  57
  58   @param SystemContext  Pointer to system register context. Mostly used by debuggers and will
  59                         update the system context after the return from the interrupt if
  60                         modified. Don't change these values unless you know what you are doing
  61
  62 **/
  63 VOID
  64 EFIAPI
  65 TimerInterruptHandler (
  66   IN  HARDWARE_INTERRUPT_SOURCE   Source,
  67   IN  EFI_SYSTEM_CONTEXT          SystemContext
  68   )
  69 {
  70   EFI_TPL OriginalTPL;
  71
  72   //
  73   // DXE core uses this callback for the EFI timer tick. The DXE core uses locks
  74   // that raise to TPL_HIGH and then restore back to current level. Thus we need
  75   // to make sure TPL level is set to TPL_HIGH while we are handling the timer tick.
  76   //
  77   OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);
  78
  79   // If the interrupt is shared then we must check if this interrupt source is the one associated to this Timer
  80   if (MmioRead32 (SP804_TIMER_PERIODIC_BASE + SP804_TIMER_MSK_INT_STS_REG) != 0) {
  81     // clear the periodic interrupt
  82     MmioWrite32 (SP804_TIMER_PERIODIC_BASE + SP804_TIMER_INT_CLR_REG, 0);
  83
  84     // signal end of interrupt early to help avoid losing subsequent ticks from long duration handlers
  85     gInterrupt->EndOfInterrupt (gInterrupt, Source);
  86
  87     if (mTimerNotifyFunction) {
  88       mTimerNotifyFunction (mTimerPeriod);
  89     }
  90   }
  91
  92   gBS->RestoreTPL (OriginalTPL);
  93 }
  94
  95 /**
  96   This function registers the handler NotifyFunction so it is called every time
  97   the timer interrupt fires.  It also passes the amount of time since the last
  98   handler call to the NotifyFunction.  If NotifyFunction is NULL, then the
  99   handler is unregistered.  If the handler is registered, then EFI_SUCCESS is
 100   returned.  If the CPU does not support registering a timer interrupt handler,
 101   then EFI_UNSUPPORTED is returned.  If an attempt is made to register a handler
 102   when a handler is already registered, then EFI_ALREADY_STARTED is returned.
 103   If an attempt is made to unregister a handler when a handler is not registered,
 104   then EFI_INVALID_PARAMETER is returned.  If an error occurs attempting to
 105   register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR
 106   is returned.
 107
 108   @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.
 109   @param  NotifyFunction   The function to call when a timer interrupt fires. This
 110                            function executes at TPL_HIGH_LEVEL. The DXE Core will
 111                            register a handler for the timer interrupt, so it can know
 112                            how much time has passed. This information is used to
 113                            signal timer based events. NULL will unregister the handler.
 114   @retval EFI_SUCCESS           The timer handler was registered.
 115   @retval EFI_UNSUPPORTED       The platform does not support timer interrupts.
 116   @retval EFI_ALREADY_STARTED   NotifyFunction is not NULL, and a handler is already
 117                                 registered.
 118   @retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not
 119                                 previously registered.
 120   @retval EFI_DEVICE_ERROR      The timer handler could not be registered.
 121
 122 **/
 123 EFI_STATUS
 124 EFIAPI
 125 TimerDriverRegisterHandler (
 126   IN EFI_TIMER_ARCH_PROTOCOL  *This,
 127   IN EFI_TIMER_NOTIFY         NotifyFunction
 128   )
 129 {
 130   if ((NotifyFunction == NULL) && (mTimerNotifyFunction == NULL)) {
 131     return EFI_INVALID_PARAMETER;
 132   }
 133
 134   if ((NotifyFunction != NULL) && (mTimerNotifyFunction != NULL)) {
 135     return EFI_ALREADY_STARTED;
 136   }
 137
 138   mTimerNotifyFunction = NotifyFunction;
 139
 140   return EFI_SUCCESS;
 141 }
 142
 143 /**
 144     Make sure all Dual Timers are disabled
 145 **/
 146 VOID
 147 EFIAPI
 148 ExitBootServicesEvent (
 149   IN EFI_EVENT  Event,
 150   IN VOID       *Context
 151   )
 152 {
 153   // Disable 'Periodic Operation' timer if enabled
 154   if (MmioRead32(SP804_TIMER_PERIODIC_BASE + SP804_TIMER_CONTROL_REG) & SP804_TIMER_CTRL_ENABLE) {
 155     MmioAnd32 (SP804_TIMER_PERIODIC_BASE + SP804_TIMER_CONTROL_REG, 0);
 156   }
 157
 158   // Disable 'Metronome/Delay' timer if enabled
 159   if (MmioRead32(SP804_TIMER_METRONOME_BASE + SP804_TIMER_CONTROL_REG) & SP804_TIMER_CTRL_ENABLE) {
 160     MmioAnd32 (SP804_TIMER_METRONOME_BASE + SP804_TIMER_CONTROL_REG, 0);
 161   }
 162
 163   // Disable 'Performance' timer if enabled
 164   if (MmioRead32(SP804_TIMER_PERFORMANCE_BASE + SP804_TIMER_CONTROL_REG) & SP804_TIMER_CTRL_ENABLE) {
 165     MmioAnd32 (SP804_TIMER_PERFORMANCE_BASE + SP804_TIMER_CONTROL_REG, 0);
 166   }
 167 }
 168
 169 /**
 170
 171   This function adjusts the period of timer interrupts to the value specified
 172   by TimerPeriod.  If the timer period is updated, then the selected timer
 173   period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned.  If
 174   the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.
 175   If an error occurs while attempting to update the timer period, then the
 176   timer hardware will be put back in its state prior to this call, and
 177   EFI_DEVICE_ERROR is returned.  If TimerPeriod is 0, then the timer interrupt
 178   is disabled.  This is not the same as disabling the CPU's interrupts.
 179   Instead, it must either turn off the timer hardware, or it must adjust the
 180   interrupt controller so that a CPU interrupt is not generated when the timer
 181   interrupt fires.
 182
 183   @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.
 184   @param  TimerPeriod      The rate to program the timer interrupt in 100 nS units. If
 185                            the timer hardware is not programmable, then EFI_UNSUPPORTED is
 186                            returned. If the timer is programmable, then the timer period
 187                            will be rounded up to the nearest timer period that is supported
 188                            by the timer hardware. If TimerPeriod is set to 0, then the
 189                            timer interrupts will be disabled.
 190
 191
 192   @retval EFI_SUCCESS           The timer period was changed.
 193   @retval EFI_UNSUPPORTED       The platform cannot change the period of the timer interrupt.
 194   @retval EFI_DEVICE_ERROR      The timer period could not be changed due to a device error.
 195
 196 **/
 197 EFI_STATUS
 198 EFIAPI
 199 TimerDriverSetTimerPeriod (
 200   IN EFI_TIMER_ARCH_PROTOCOL  *This,
 201   IN UINT64                   TimerPeriod
 202   )
 203 {
 204   EFI_STATUS  Status;
 205   UINT64      TimerTicks;
 206
 207   // always disable the timer
 208   MmioAnd32 (SP804_TIMER_PERIODIC_BASE + SP804_TIMER_CONTROL_REG, ~SP804_TIMER_CTRL_ENABLE);
 209
 210   if (TimerPeriod == 0) {
 211     // Leave timer disabled from above, and...
 212
 213     // Disable timer 0/1 interrupt for a TimerPeriod of 0
 214     Status = gInterrupt->DisableInterruptSource (gInterrupt, gVector);
 215   } else {
 216     // Convert TimerPeriod into 1MHz clock counts (us units = 100ns units / 10)
 217     TimerTicks = DivU64x32 (TimerPeriod, 10);
 218     TimerTicks = MultU64x32 (TimerTicks, PcdGet32(PcdSP804TimerFrequencyInMHz));
 219
 220     // if it's larger than 32-bits, pin to highest value
 221     if (TimerTicks > 0xffffffff) {
 222
 223       TimerTicks = 0xffffffff;
 224
 225     }
 226
 227     // Program the SP804 timer with the new count value
 228     MmioWrite32 (SP804_TIMER_PERIODIC_BASE + SP804_TIMER_LOAD_REG, TimerTicks);
 229
 230     // enable the timer
 231     MmioOr32 (SP804_TIMER_PERIODIC_BASE + SP804_TIMER_CONTROL_REG, SP804_TIMER_CTRL_ENABLE);
 232
 233     // enable timer 0/1 interrupts
 234     Status = gInterrupt->EnableInterruptSource (gInterrupt, gVector);
 235   }
 236
 237   // Save the new timer period
 238   mTimerPeriod = TimerPeriod;
 239   return Status;
 240 }
 241
 242 /**
 243   This function retrieves the period of timer interrupts in 100 ns units,
 244   returns that value in TimerPeriod, and returns EFI_SUCCESS.  If TimerPeriod
 245   is NULL, then EFI_INVALID_PARAMETER is returned.  If a TimerPeriod of 0 is
 246   returned, then the timer is currently disabled.
 247
 248   @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.
 249   @param  TimerPeriod      A pointer to the timer period to retrieve in 100 ns units. If
 250                            0 is returned, then the timer is currently disabled.
 251
 252
 253   @retval EFI_SUCCESS           The timer period was returned in TimerPeriod.
 254   @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.
 255
 256 **/
 257 EFI_STATUS
 258 EFIAPI
 259 TimerDriverGetTimerPeriod (
 260   IN EFI_TIMER_ARCH_PROTOCOL   *This,
 261   OUT UINT64                   *TimerPeriod
 262   )
 263 {
 264   if (TimerPeriod == NULL) {
 265     return EFI_INVALID_PARAMETER;
 266   }
 267
 268   *TimerPeriod = mTimerPeriod;
 269   return EFI_SUCCESS;
 270 }
 271
 272 /**
 273   This function generates a soft timer interrupt. If the platform does not support soft
 274   timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.
 275   If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()
 276   service, then a soft timer interrupt will be generated. If the timer interrupt is
 277   enabled when this service is called, then the registered handler will be invoked. The
 278   registered handler should not be able to distinguish a hardware-generated timer
 279   interrupt from a software-generated timer interrupt.
 280
 281   @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.
 282
 283   @retval EFI_SUCCESS           The soft timer interrupt was generated.
 284   @retval EFI_UNSUPPORTED       The platform does not support the generation of soft timer interrupts.
 285
 286 **/
 287 EFI_STATUS
 288 EFIAPI
 289 TimerDriverGenerateSoftInterrupt (
 290   IN EFI_TIMER_ARCH_PROTOCOL  *This
 291   )
 292 {
 293   return EFI_UNSUPPORTED;
 294 }
 295
 296 /**
 297   Interface structure for the Timer Architectural Protocol.
 298
 299   @par Protocol Description:
 300   This protocol provides the services to initialize a periodic timer
 301   interrupt, and to register a handler that is called each time the timer
 302   interrupt fires.  It may also provide a service to adjust the rate of the
 303   periodic timer interrupt.  When a timer interrupt occurs, the handler is
 304   passed the amount of time that has passed since the previous timer
 305   interrupt.
 306
 307   @param RegisterHandler
 308   Registers a handler that will be called each time the
 309   timer interrupt fires.  TimerPeriod defines the minimum
 310   time between timer interrupts, so TimerPeriod will also
 311   be the minimum time between calls to the registered
 312   handler.
 313
 314   @param SetTimerPeriod
 315   Sets the period of the timer interrupt in 100 nS units.
 316   This function is optional, and may return EFI_UNSUPPORTED.
 317   If this function is supported, then the timer period will
 318   be rounded up to the nearest supported timer period.
 319
 320
 321   @param GetTimerPeriod
 322   Retrieves the period of the timer interrupt in 100 nS units.
 323
 324   @param GenerateSoftInterrupt
 325   Generates a soft timer interrupt that simulates the firing of
 326   the timer interrupt. This service can be used to invoke the   registered handler if the timer interrupt has been masked for
 327   a period of time.
 328
 329 **/
 330 EFI_TIMER_ARCH_PROTOCOL   gTimer = {
 331   TimerDriverRegisterHandler,
 332   TimerDriverSetTimerPeriod,
 333   TimerDriverGetTimerPeriod,
 334   TimerDriverGenerateSoftInterrupt
 335 };
 336
 337
 338 /**
 339   Initialize the state information for the Timer Architectural Protocol and
 340   the Timer Debug support protocol that allows the debugger to break into a
 341   running program.
 342
 343   @param  ImageHandle   of the loaded driver
 344   @param  SystemTable   Pointer to the System Table
 345
 346   @retval EFI_SUCCESS           Protocol registered
 347   @retval EFI_OUT_OF_RESOURCES  Cannot allocate protocol data structure
 348   @retval EFI_DEVICE_ERROR      Hardware problems
 349
 350 **/
 351 EFI_STATUS
 352 EFIAPI
 353 TimerInitialize (
 354   IN EFI_HANDLE         ImageHandle,
 355   IN EFI_SYSTEM_TABLE   *SystemTable
 356   )
 357 {
 358   EFI_HANDLE  Handle = NULL;
 359   EFI_STATUS  Status;
 360
 361   // Find the interrupt controller protocol.  ASSERT if not found.
 362   Status = gBS->LocateProtocol (&gHardwareInterruptProtocolGuid, NULL, (VOID **)&gInterrupt);
 363   ASSERT_EFI_ERROR (Status);
 364
 365   // Disable the timer
 366   Status = TimerDriverSetTimerPeriod (&gTimer, 0);
 367   ASSERT_EFI_ERROR (Status);
 368
 369   // Install interrupt handler
 370   gVector = PcdGet32(PcdSP804TimerPeriodicInterruptNum);
 371   Status = gInterrupt->RegisterInterruptSource (gInterrupt, gVector, TimerInterruptHandler);
 372   ASSERT_EFI_ERROR (Status);
 373
 374   // configure timer 0 for periodic operation, 32 bits, no prescaler, and interrupt enabled
 375   MmioWrite32 (SP804_TIMER_PERIODIC_BASE + SP804_TIMER_CONTROL_REG, SP804_TIMER_CTRL_PERIODIC | SP804_TIMER_CTRL_32BIT | SP804_PRESCALE_DIV_1 | SP804_TIMER_CTRL_INT_ENABLE);
 376
 377   // Set up default timer
 378   Status = TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod)); // TIMER_DEFAULT_PERIOD
 379   ASSERT_EFI_ERROR (Status);
 380
 381   // Install the Timer Architectural Protocol onto a new handle
 382   Status = gBS->InstallMultipleProtocolInterfaces(
 383                   &Handle,
 384                   &gEfiTimerArchProtocolGuid,      &gTimer,
 385                   NULL
 386                   );
 387   ASSERT_EFI_ERROR(Status);
 388
 389   // Register for an ExitBootServicesEvent
 390   Status = gBS->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_NOTIFY, ExitBootServicesEvent, NULL, &EfiExitBootServicesEvent);
 391   ASSERT_EFI_ERROR (Status);
 392
 393   return Status;
 394 }