Omap35xxPkg/TimerDxe/Timer.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 #include <Library/OmapLib.h>
  27
  28 #include <Protocol/Timer.h>
  29 #include <Protocol/HardwareInterrupt.h>
  30
  31 #include <Omap3530/Omap3530.h>
  32
  33
  34 // The notification function to call on every timer interrupt.
  35 volatile EFI_TIMER_NOTIFY      mTimerNotifyFunction   = (EFI_TIMER_NOTIFY)NULL;
  36
  37
  38 // The current period of the timer interrupt
  39 volatile UINT64 mTimerPeriod = 0;
  40
  41 // Cached copy of the Hardware Interrupt protocol instance
  42 EFI_HARDWARE_INTERRUPT_PROTOCOL *gInterrupt = NULL;
  43
  44 // Cached registers
  45 volatile UINT32 TISR;
  46 volatile UINT32 TCLR;
  47 volatile UINT32 TLDR;
  48 volatile UINT32 TCRR;
  49 volatile UINT32 TIER;
  50
  51 // Cached interrupt vector
  52 volatile UINTN  gVector;
  53
  54
  55 /**
  56
  57   C Interrupt Handler calledin the interrupt context when Source interrupt is active.
  58
  59
  60   @param Source         Source of the interrupt. Hardware routing off a specific platform defines
  61                         what source means.
  62
  63   @param SystemContext  Pointer to system register context. Mostly used by debuggers and will
  64                         update the system context after the return from the interrupt if
  65                         modified. Don't change these values unless you know what you are doing
  66
  67 **/
  68 VOID
  69 EFIAPI
  70 TimerInterruptHandler (
  71   IN  HARDWARE_INTERRUPT_SOURCE   Source,
  72   IN  EFI_SYSTEM_CONTEXT          SystemContext
  73   )
  74 {
  75   EFI_TPL OriginalTPL;
  76
  77
  78
  79   //
  80   // DXE core uses this callback for the EFI timer tick. The DXE core uses locks
  81   // that raise to TPL_HIGH and then restore back to current level. Thus we need
  82   // to make sure TPL level is set to TPL_HIGH while we are handling the timer tick.
  83   //
  84   OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);
  85
  86   if (mTimerNotifyFunction) {
  87     mTimerNotifyFunction(mTimerPeriod);
  88   }
  89
  90   // Clear all timer interrupts
  91   MmioWrite32 (TISR, TISR_CLEAR_ALL);
  92
  93   // Poll interrupt status bits to ensure clearing
  94   while ((MmioRead32 (TISR) & TISR_ALL_INTERRUPT_MASK) != TISR_NO_INTERRUPTS_PENDING);
  95
  96   gBS->RestoreTPL (OriginalTPL);
  97 }
  98
  99 /**
 100   This function registers the handler NotifyFunction so it is called every time
 101   the timer interrupt fires.  It also passes the amount of time since the last
 102   handler call to the NotifyFunction.  If NotifyFunction is NULL, then the
 103   handler is unregistered.  If the handler is registered, then EFI_SUCCESS is
 104   returned.  If the CPU does not support registering a timer interrupt handler,
 105   then EFI_UNSUPPORTED is returned.  If an attempt is made to register a handler
 106   when a handler is already registered, then EFI_ALREADY_STARTED is returned.
 107   If an attempt is made to unregister a handler when a handler is not registered,
 108   then EFI_INVALID_PARAMETER is returned.  If an error occurs attempting to
 109   register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR
 110   is returned.
 111
 112   @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.
 113   @param  NotifyFunction   The function to call when a timer interrupt fires. This
 114                            function executes at TPL_HIGH_LEVEL. The DXE Core will
 115                            register a handler for the timer interrupt, so it can know
 116                            how much time has passed. This information is used to
 117                            signal timer based events. NULL will unregister the handler.
 118   @retval EFI_SUCCESS           The timer handler was registered.
 119   @retval EFI_UNSUPPORTED       The platform does not support timer interrupts.
 120   @retval EFI_ALREADY_STARTED   NotifyFunction is not NULL, and a handler is already
 121                                 registered.
 122   @retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not
 123                                 previously registered.
 124   @retval EFI_DEVICE_ERROR      The timer handler could not be registered.
 125
 126 **/
 127 EFI_STATUS
 128 EFIAPI
 129 TimerDriverRegisterHandler (
 130   IN EFI_TIMER_ARCH_PROTOCOL  *This,
 131   IN EFI_TIMER_NOTIFY         NotifyFunction
 132   )
 133 {
 134   if ((NotifyFunction == NULL) && (mTimerNotifyFunction == NULL)) {
 135     return EFI_INVALID_PARAMETER;
 136   }
 137
 138   if ((NotifyFunction != NULL) && (mTimerNotifyFunction != NULL)) {
 139     return EFI_ALREADY_STARTED;
 140   }
 141
 142   mTimerNotifyFunction = NotifyFunction;
 143
 144   return EFI_SUCCESS;
 145 }
 146
 147 /**
 148
 149   This function adjusts the period of timer interrupts to the value specified
 150   by TimerPeriod.  If the timer period is updated, then the selected timer
 151   period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned.  If
 152   the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.
 153   If an error occurs while attempting to update the timer period, then the
 154   timer hardware will be put back in its state prior to this call, and
 155   EFI_DEVICE_ERROR is returned.  If TimerPeriod is 0, then the timer interrupt
 156   is disabled.  This is not the same as disabling the CPU's interrupts.
 157   Instead, it must either turn off the timer hardware, or it must adjust the
 158   interrupt controller so that a CPU interrupt is not generated when the timer
 159   interrupt fires.
 160
 161   @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.
 162   @param  TimerPeriod      The rate to program the timer interrupt in 100 nS units. If
 163                            the timer hardware is not programmable, then EFI_UNSUPPORTED is
 164                            returned. If the timer is programmable, then the timer period
 165                            will be rounded up to the nearest timer period that is supported
 166                            by the timer hardware. If TimerPeriod is set to 0, then the
 167                            timer interrupts will be disabled.
 168
 169
 170   @retval EFI_SUCCESS           The timer period was changed.
 171   @retval EFI_UNSUPPORTED       The platform cannot change the period of the timer interrupt.
 172   @retval EFI_DEVICE_ERROR      The timer period could not be changed due to a device error.
 173
 174 **/
 175 EFI_STATUS
 176 EFIAPI
 177 TimerDriverSetTimerPeriod (
 178   IN EFI_TIMER_ARCH_PROTOCOL  *This,
 179   IN UINT64                   TimerPeriod
 180   )
 181 {
 182   EFI_STATUS  Status;
 183   UINT64      TimerCount;
 184   INT32       LoadValue;
 185
 186   if (TimerPeriod == 0) {
 187     // Turn off GPTIMER3
 188     MmioWrite32 (TCLR, TCLR_ST_OFF);
 189
 190     Status = gInterrupt->DisableInterruptSource(gInterrupt, gVector);
 191   } else {
 192     // Calculate required timer count
 193     TimerCount = DivU64x32(TimerPeriod * 100, PcdGet32(PcdEmbeddedPerformanceCounterPeriodInNanoseconds));
 194
 195     // Set GPTIMER3 Load register
 196     LoadValue = (INT32) -TimerCount;
 197     MmioWrite32 (TLDR, LoadValue);
 198     MmioWrite32 (TCRR, LoadValue);
 199
 200     // Enable Overflow interrupt
 201     MmioWrite32 (TIER, TIER_TCAR_IT_DISABLE | TIER_OVF_IT_ENABLE | TIER_MAT_IT_DISABLE);
 202
 203     // Turn on GPTIMER3, it will reload at overflow
 204     MmioWrite32 (TCLR, TCLR_AR_AUTORELOAD | TCLR_ST_ON);
 205
 206     Status = gInterrupt->EnableInterruptSource(gInterrupt, gVector);
 207   }
 208
 209   //
 210   // Save the new timer period
 211   //
 212   mTimerPeriod = TimerPeriod;
 213   return Status;
 214 }
 215
 216
 217 /**
 218   This function retrieves the period of timer interrupts in 100 ns units,
 219   returns that value in TimerPeriod, and returns EFI_SUCCESS.  If TimerPeriod
 220   is NULL, then EFI_INVALID_PARAMETER is returned.  If a TimerPeriod of 0 is
 221   returned, then the timer is currently disabled.
 222
 223   @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.
 224   @param  TimerPeriod      A pointer to the timer period to retrieve in 100 ns units. If
 225                            0 is returned, then the timer is currently disabled.
 226
 227
 228   @retval EFI_SUCCESS           The timer period was returned in TimerPeriod.
 229   @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.
 230
 231 **/
 232 EFI_STATUS
 233 EFIAPI
 234 TimerDriverGetTimerPeriod (
 235   IN EFI_TIMER_ARCH_PROTOCOL   *This,
 236   OUT UINT64                   *TimerPeriod
 237   )
 238 {
 239   if (TimerPeriod == NULL) {
 240     return EFI_INVALID_PARAMETER;
 241   }
 242
 243   *TimerPeriod = mTimerPeriod;
 244   return EFI_SUCCESS;
 245 }
 246
 247 /**
 248   This function generates a soft timer interrupt. If the platform does not support soft
 249   timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.
 250   If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()
 251   service, then a soft timer interrupt will be generated. If the timer interrupt is
 252   enabled when this service is called, then the registered handler will be invoked. The
 253   registered handler should not be able to distinguish a hardware-generated timer
 254   interrupt from a software-generated timer interrupt.
 255
 256   @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.
 257
 258   @retval EFI_SUCCESS           The soft timer interrupt was generated.
 259   @retval EFI_UNSUPPORTED       The platform does not support the generation of soft timer interrupts.
 260
 261 **/
 262 EFI_STATUS
 263 EFIAPI
 264 TimerDriverGenerateSoftInterrupt (
 265   IN EFI_TIMER_ARCH_PROTOCOL  *This
 266   )
 267 {
 268   return EFI_UNSUPPORTED;
 269 }
 270
 271
 272 /**
 273   Interface stucture for the Timer Architectural Protocol.
 274
 275   @par Protocol Description:
 276   This protocol provides the services to initialize a periodic timer
 277   interrupt, and to register a handler that is called each time the timer
 278   interrupt fires.  It may also provide a service to adjust the rate of the
 279   periodic timer interrupt.  When a timer interrupt occurs, the handler is
 280   passed the amount of time that has passed since the previous timer
 281   interrupt.
 282
 283   @param RegisterHandler
 284   Registers a handler that will be called each time the
 285   timer interrupt fires.  TimerPeriod defines the minimum
 286   time between timer interrupts, so TimerPeriod will also
 287   be the minimum time between calls to the registered
 288   handler.
 289
 290   @param SetTimerPeriod
 291   Sets the period of the timer interrupt in 100 nS units.
 292   This function is optional, and may return EFI_UNSUPPORTED.
 293   If this function is supported, then the timer period will
 294   be rounded up to the nearest supported timer period.
 295
 296
 297   @param GetTimerPeriod
 298   Retrieves the period of the timer interrupt in 100 nS units.
 299
 300   @param GenerateSoftInterrupt
 301   Generates a soft timer interrupt that simulates the firing of
 302   the timer interrupt. This service can be used to invoke the   registered handler if the timer interrupt has been masked for
 303   a period of time.
 304
 305 **/
 306 EFI_TIMER_ARCH_PROTOCOL   gTimer = {
 307   TimerDriverRegisterHandler,
 308   TimerDriverSetTimerPeriod,
 309   TimerDriverGetTimerPeriod,
 310   TimerDriverGenerateSoftInterrupt
 311 };
 312
 313
 314 /**
 315   Initialize the state information for the Timer Architectural Protocol and
 316   the Timer Debug support protocol that allows the debugger to break into a
 317   running program.
 318
 319   @param  ImageHandle   of the loaded driver
 320   @param  SystemTable   Pointer to the System Table
 321
 322   @retval EFI_SUCCESS           Protocol registered
 323   @retval EFI_OUT_OF_RESOURCES  Cannot allocate protocol data structure
 324   @retval EFI_DEVICE_ERROR      Hardware problems
 325
 326 **/
 327 EFI_STATUS
 328 EFIAPI
 329 TimerInitialize (
 330   IN EFI_HANDLE         ImageHandle,
 331   IN EFI_SYSTEM_TABLE   *SystemTable
 332   )
 333 {
 334   EFI_HANDLE  Handle = NULL;
 335   EFI_STATUS  Status;
 336   UINT32      TimerBaseAddress;
 337
 338   // Find the interrupt controller protocol.  ASSERT if not found.
 339   Status = gBS->LocateProtocol (&gHardwareInterruptProtocolGuid, NULL, (VOID **)&gInterrupt);
 340   ASSERT_EFI_ERROR (Status);
 341
 342   // Set up the timer registers
 343   TimerBaseAddress = TimerBase (FixedPcdGet32(PcdOmap35xxArchTimer));
 344   TISR = TimerBaseAddress + GPTIMER_TISR;
 345   TCLR = TimerBaseAddress + GPTIMER_TCLR;
 346   TLDR = TimerBaseAddress + GPTIMER_TLDR;
 347   TCRR = TimerBaseAddress + GPTIMER_TCRR;
 348   TIER = TimerBaseAddress + GPTIMER_TIER;
 349
 350   // Disable the timer
 351   Status = TimerDriverSetTimerPeriod (&gTimer, 0);
 352   ASSERT_EFI_ERROR (Status);
 353
 354   // Install interrupt handler
 355   gVector = InterruptVectorForTimer (FixedPcdGet32(PcdOmap35xxArchTimer));
 356   Status = gInterrupt->RegisterInterruptSource (gInterrupt, gVector, TimerInterruptHandler);
 357   ASSERT_EFI_ERROR (Status);
 358
 359   // Set up default timer
 360   Status = TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod));
 361   ASSERT_EFI_ERROR (Status);
 362
 363   // Install the Timer Architectural Protocol onto a new handle
 364   Status = gBS->InstallMultipleProtocolInterfaces (
 365                   &Handle,
 366                   &gEfiTimerArchProtocolGuid,      &gTimer,
 367                   NULL
 368                   );
 369   ASSERT_EFI_ERROR(Status);
 370
 371   return Status;
 372 }
 373