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 #include <ArmPlatform.h>
  32
  33 // The notification function to call on every timer interrupt.
  34 volatile EFI_TIMER_NOTIFY      mTimerNotifyFunction   = (EFI_TIMER_NOTIFY)NULL;
  35 EFI_EVENT                       EfiExitBootServicesEvent        = (EFI_EVENT)NULL;
  36
  37 // The current period of the timer interrupt
  38 volatile UINT64 mTimerPeriod = 0;
  39
  40 // Cached copy of the Hardware Interrupt protocol instance
  41 EFI_HARDWARE_INTERRUPT_PROTOCOL *gInterrupt = NULL;
  42
  43 // Cached interrupt vector
  44 UINTN  gVector;
  45
  46 UINT32 mLastTickCount;
  47
  48 /**
  49
  50   C Interrupt Handler called in the interrupt context when Source interrupt is active.
  51
  52
  53   @param Source         Source of the interrupt. Hardware routing off a specific platform defines
  54                         what source means.
  55
  56   @param SystemContext  Pointer to system register context. Mostly used by debuggers and will
  57                         update the system context after the return from the interrupt if
  58                         modified. Don't change these values unless you know what you are doing
  59
  60 **/
  61 VOID
  62 EFIAPI
  63 TimerInterruptHandler (
  64   IN  HARDWARE_INTERRUPT_SOURCE   Source,
  65   IN  EFI_SYSTEM_CONTEXT          SystemContext
  66   )
  67 {
  68   EFI_TPL OriginalTPL;
  69
  70   //
  71   // DXE core uses this callback for the EFI timer tick. The DXE core uses locks
  72   // that raise to TPL_HIGH and then restore back to current level. Thus we need
  73   // to make sure TPL level is set to TPL_HIGH while we are handling the timer tick.
  74   //
  75   OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);
  76
  77   // If the interrupt is shared then we must check if this interrupt source is the one associated to this Timer
  78   if (MmioRead32 (SP804_TIMER0_BASE + SP804_TIMER_MSK_INT_STS_REG) != 0) {
  79     // clear the periodic interrupt
  80     MmioWrite32 (SP804_TIMER0_BASE + SP804_TIMER_INT_CLR_REG, 0);
  81
  82     // signal end of interrupt early to help avoid losing subsequent ticks from long duration handlers
  83     gInterrupt->EndOfInterrupt (gInterrupt, Source);
  84
  85     if (mTimerNotifyFunction) {
  86       mTimerNotifyFunction (mTimerPeriod);
  87     }
  88   }
  89
  90   gBS->RestoreTPL (OriginalTPL);
  91 }
  92
  93 /**
  94   This function registers the handler NotifyFunction so it is called every time
  95   the timer interrupt fires.  It also passes the amount of time since the last
  96   handler call to the NotifyFunction.  If NotifyFunction is NULL, then the
  97   handler is unregistered.  If the handler is registered, then EFI_SUCCESS is
  98   returned.  If the CPU does not support registering a timer interrupt handler,
  99   then EFI_UNSUPPORTED is returned.  If an attempt is made to register a handler
 100   when a handler is already registered, then EFI_ALREADY_STARTED is returned.
 101   If an attempt is made to unregister a handler when a handler is not registered,
 102   then EFI_INVALID_PARAMETER is returned.  If an error occurs attempting to
 103   register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR
 104   is returned.
 105
 106   @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.
 107   @param  NotifyFunction   The function to call when a timer interrupt fires. This
 108                            function executes at TPL_HIGH_LEVEL. The DXE Core will
 109                            register a handler for the timer interrupt, so it can know
 110                            how much time has passed. This information is used to
 111                            signal timer based events. NULL will unregister the handler.
 112   @retval EFI_SUCCESS           The timer handler was registered.
 113   @retval EFI_UNSUPPORTED       The platform does not support timer interrupts.
 114   @retval EFI_ALREADY_STARTED   NotifyFunction is not NULL, and a handler is already
 115                                 registered.
 116   @retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not
 117                                 previously registered.
 118   @retval EFI_DEVICE_ERROR      The timer handler could not be registered.
 119
 120 **/
 121 EFI_STATUS
 122 EFIAPI
 123 TimerDriverRegisterHandler (
 124   IN EFI_TIMER_ARCH_PROTOCOL  *This,
 125   IN EFI_TIMER_NOTIFY         NotifyFunction
 126   )
 127 {
 128   if ((NotifyFunction == NULL) && (mTimerNotifyFunction == NULL)) {
 129     return EFI_INVALID_PARAMETER;
 130   }
 131
 132   if ((NotifyFunction != NULL) && (mTimerNotifyFunction != NULL)) {
 133     return EFI_ALREADY_STARTED;
 134   }
 135
 136   mTimerNotifyFunction = NotifyFunction;
 137
 138   return EFI_SUCCESS;
 139 }
 140
 141 /**
 142     Make sure all ArrmVe Timers are disabled
 143 **/
 144 VOID
 145 EFIAPI
 146 ExitBootServicesEvent (
 147   IN EFI_EVENT  Event,
 148   IN VOID       *Context
 149   )
 150 {
 151     // Disable timer 0 if enabled
 152     if (MmioRead32(SP804_TIMER0_BASE + SP804_TIMER_CONTROL_REG) & SP804_TIMER_CTRL_ENABLE) {
 153         MmioAnd32 (SP804_TIMER0_BASE + SP804_TIMER_CONTROL_REG, 0);
 154     }
 155
 156     // Disable timer 1 if enabled
 157     if (MmioRead32(SP804_TIMER1_BASE + SP804_TIMER_CONTROL_REG) & SP804_TIMER_CTRL_ENABLE) {
 158         MmioAnd32 (SP804_TIMER1_BASE + SP804_TIMER_CONTROL_REG, 0);
 159     }
 160
 161     // Disable timer 2 if enabled
 162     if (MmioRead32(SP804_TIMER2_BASE + SP804_TIMER_CONTROL_REG) & SP804_TIMER_CTRL_ENABLE) {
 163         MmioAnd32 (SP804_TIMER2_BASE + SP804_TIMER_CONTROL_REG, 0);
 164     }
 165
 166     // Disable timer 3 if enabled
 167     if (MmioRead32(SP804_TIMER3_BASE + SP804_TIMER_CONTROL_REG) & SP804_TIMER_CTRL_ENABLE) {
 168         MmioAnd32 (SP804_TIMER3_BASE + SP804_TIMER_CONTROL_REG, 0);
 169     }
 170 }
 171
 172 /**
 173
 174   This function adjusts the period of timer interrupts to the value specified
 175   by TimerPeriod.  If the timer period is updated, then the selected timer
 176   period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned.  If
 177   the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.
 178   If an error occurs while attempting to update the timer period, then the
 179   timer hardware will be put back in its state prior to this call, and
 180   EFI_DEVICE_ERROR is returned.  If TimerPeriod is 0, then the timer interrupt
 181   is disabled.  This is not the same as disabling the CPU's interrupts.
 182   Instead, it must either turn off the timer hardware, or it must adjust the
 183   interrupt controller so that a CPU interrupt is not generated when the timer
 184   interrupt fires.
 185
 186   @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.
 187   @param  TimerPeriod      The rate to program the timer interrupt in 100 nS units. If
 188                            the timer hardware is not programmable, then EFI_UNSUPPORTED is
 189                            returned. If the timer is programmable, then the timer period
 190                            will be rounded up to the nearest timer period that is supported
 191                            by the timer hardware. If TimerPeriod is set to 0, then the
 192                            timer interrupts will be disabled.
 193
 194
 195   @retval EFI_SUCCESS           The timer period was changed.
 196   @retval EFI_UNSUPPORTED       The platform cannot change the period of the timer interrupt.
 197   @retval EFI_DEVICE_ERROR      The timer period could not be changed due to a device error.
 198
 199 **/
 200 EFI_STATUS
 201 EFIAPI
 202 TimerDriverSetTimerPeriod (
 203   IN EFI_TIMER_ARCH_PROTOCOL  *This,
 204   IN UINT64                   TimerPeriod
 205   )
 206 {
 207   EFI_STATUS  Status;
 208   UINT64      TimerTicks;
 209
 210   // always disable the timer
 211   MmioAnd32 (SP804_TIMER0_BASE + SP804_TIMER_CONTROL_REG, ~SP804_TIMER_CTRL_ENABLE);
 212
 213   if (TimerPeriod == 0) {
 214     // Leave timer disabled from above, and...
 215
 216     // Disable timer 0/1 interrupt for a TimerPeriod of 0
 217     Status = gInterrupt->DisableInterruptSource (gInterrupt, gVector);
 218   } else {
 219     // Convert TimerPeriod into 1MHz clock counts (us units = 100ns units / 10)
 220     TimerTicks = DivU64x32 (TimerPeriod, 10);
 221
 222     // if it's larger than 32-bits, pin to highest value
 223     if (TimerTicks > 0xffffffff) {
 224
 225       TimerTicks = 0xffffffff;
 226
 227     }
 228
 229     // Program the SP804 timer with the new count value
 230     MmioWrite32 (SP804_TIMER0_BASE + SP804_TIMER_LOAD_REG, TimerTicks);
 231
 232     // enable the timer
 233     MmioOr32 (SP804_TIMER0_BASE + SP804_TIMER_CONTROL_REG, SP804_TIMER_CTRL_ENABLE);
 234
 235     // enable timer 0/1 interrupts
 236     Status = gInterrupt->EnableInterruptSource (gInterrupt, gVector);
 237   }
 238
 239   // Save the new timer period
 240   mTimerPeriod = TimerPeriod;
 241   return Status;
 242 }
 243
 244 /**
 245   This function retrieves the period of timer interrupts in 100 ns units,
 246   returns that value in TimerPeriod, and returns EFI_SUCCESS.  If TimerPeriod
 247   is NULL, then EFI_INVALID_PARAMETER is returned.  If a TimerPeriod of 0 is
 248   returned, then the timer is currently disabled.
 249
 250   @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.
 251   @param  TimerPeriod      A pointer to the timer period to retrieve in 100 ns units. If
 252                            0 is returned, then the timer is currently disabled.
 253
 254
 255   @retval EFI_SUCCESS           The timer period was returned in TimerPeriod.
 256   @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.
 257
 258 **/
 259 EFI_STATUS
 260 EFIAPI
 261 TimerDriverGetTimerPeriod (
 262   IN EFI_TIMER_ARCH_PROTOCOL   *This,
 263   OUT UINT64                   *TimerPeriod
 264   )
 265 {
 266   if (TimerPeriod == NULL) {
 267     return EFI_INVALID_PARAMETER;
 268   }
 269
 270   *TimerPeriod = mTimerPeriod;
 271   return EFI_SUCCESS;
 272 }
 273
 274 /**
 275   This function generates a soft timer interrupt. If the platform does not support soft
 276   timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.
 277   If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()
 278   service, then a soft timer interrupt will be generated. If the timer interrupt is
 279   enabled when this service is called, then the registered handler will be invoked. The
 280   registered handler should not be able to distinguish a hardware-generated timer
 281   interrupt from a software-generated timer interrupt.
 282
 283   @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.
 284
 285   @retval EFI_SUCCESS           The soft timer interrupt was generated.
 286   @retval EFI_UNSUPPORTED       The platform does not support the generation of soft timer interrupts.
 287
 288 **/
 289 EFI_STATUS
 290 EFIAPI
 291 TimerDriverGenerateSoftInterrupt (
 292   IN EFI_TIMER_ARCH_PROTOCOL  *This
 293   )
 294 {
 295   return EFI_UNSUPPORTED;
 296 }
 297
 298 /**
 299   Interface structure for the Timer Architectural Protocol.
 300
 301   @par Protocol Description:
 302   This protocol provides the services to initialize a periodic timer
 303   interrupt, and to register a handler that is called each time the timer
 304   interrupt fires.  It may also provide a service to adjust the rate of the
 305   periodic timer interrupt.  When a timer interrupt occurs, the handler is
 306   passed the amount of time that has passed since the previous timer
 307   interrupt.
 308
 309   @param RegisterHandler
 310   Registers a handler that will be called each time the
 311   timer interrupt fires.  TimerPeriod defines the minimum
 312   time between timer interrupts, so TimerPeriod will also
 313   be the minimum time between calls to the registered
 314   handler.
 315
 316   @param SetTimerPeriod
 317   Sets the period of the timer interrupt in 100 nS units.
 318   This function is optional, and may return EFI_UNSUPPORTED.
 319   If this function is supported, then the timer period will
 320   be rounded up to the nearest supported timer period.
 321
 322
 323   @param GetTimerPeriod
 324   Retrieves the period of the timer interrupt in 100 nS units.
 325
 326   @param GenerateSoftInterrupt
 327   Generates a soft timer interrupt that simulates the firing of
 328   the timer interrupt. This service can be used to invoke the   registered handler if the timer interrupt has been masked for
 329   a period of time.
 330
 331 **/
 332 EFI_TIMER_ARCH_PROTOCOL   gTimer = {
 333   TimerDriverRegisterHandler,
 334   TimerDriverSetTimerPeriod,
 335   TimerDriverGetTimerPeriod,
 336   TimerDriverGenerateSoftInterrupt
 337 };
 338
 339
 340 /**
 341   Initialize the state information for the Timer Architectural Protocol and
 342   the Timer Debug support protocol that allows the debugger to break into a
 343   running program.
 344
 345   @param  ImageHandle   of the loaded driver
 346   @param  SystemTable   Pointer to the System Table
 347
 348   @retval EFI_SUCCESS           Protocol registered
 349   @retval EFI_OUT_OF_RESOURCES  Cannot allocate protocol data structure
 350   @retval EFI_DEVICE_ERROR      Hardware problems
 351
 352 **/
 353 EFI_STATUS
 354 EFIAPI
 355 TimerInitialize (
 356   IN EFI_HANDLE         ImageHandle,
 357   IN EFI_SYSTEM_TABLE   *SystemTable
 358   )
 359 {
 360   EFI_HANDLE  Handle = NULL;
 361   EFI_STATUS  Status;
 362
 363   // Find the interrupt controller protocol.  ASSERT if not found.
 364   Status = gBS->LocateProtocol (&gHardwareInterruptProtocolGuid, NULL, (VOID **)&gInterrupt);
 365   ASSERT_EFI_ERROR (Status);
 366
 367   // Configure timer 1 for free running operation, 32 bits, no prescaler, interrupt disabled
 368   MmioWrite32 (SP804_TIMER1_BASE + SP804_TIMER_CONTROL_REG, SP804_TIMER_CTRL_32BIT | SP804_PRESCALE_DIV_1);
 369
 370   // Enable the free running timer
 371   MmioOr32 (SP804_TIMER1_BASE + SP804_TIMER_CONTROL_REG, SP804_TIMER_CTRL_ENABLE);
 372
 373   // Record free running tick value (should be close to 0xffffffff)
 374   mLastTickCount = MmioRead32 (SP804_TIMER1_BASE + SP804_TIMER_CURRENT_REG);
 375
 376   // Disable the timer
 377   Status = TimerDriverSetTimerPeriod (&gTimer, 0);
 378   ASSERT_EFI_ERROR (Status);
 379
 380   // Install interrupt handler
 381   gVector = TIMER01_INTERRUPT_NUM;
 382   Status = gInterrupt->RegisterInterruptSource (gInterrupt, gVector, TimerInterruptHandler);
 383   ASSERT_EFI_ERROR (Status);
 384
 385   // configure timer 0 for periodic operation, 32 bits, no prescaler, and interrupt enabled
 386   MmioWrite32 (SP804_TIMER0_BASE + SP804_TIMER_CONTROL_REG, SP804_TIMER_CTRL_PERIODIC | SP804_TIMER_CTRL_32BIT | SP804_PRESCALE_DIV_1 | SP804_TIMER_CTRL_INT_ENABLE);
 387
 388   // Set up default timer
 389   Status = TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod)); // TIMER_DEFAULT_PERIOD
 390   ASSERT_EFI_ERROR (Status);
 391
 392   // Install the Timer Architectural Protocol onto a new handle
 393   Status = gBS->InstallMultipleProtocolInterfaces(
 394                   &Handle,
 395                   &gEfiTimerArchProtocolGuid,      &gTimer,
 396                   NULL
 397                   );
 398   ASSERT_EFI_ERROR(Status);
 399
 400   // Register for an ExitBootServicesEvent
 401   Status = gBS->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_NOTIFY, ExitBootServicesEvent, NULL, &EfiExitBootServicesEvent);
 402   ASSERT_EFI_ERROR (Status);
 403
 404   return Status;
 405 }