MdeModulePkg/Universal/WatchDogTimerDxe/WatchDogTimer.c

   1 /*++
   2
   3 Copyright (c) 2006, Intel Corporation
   4 All rights reserved. This program and the accompanying materials
   5 are licensed and made available under the terms and conditions of the BSD License
   6 which accompanies this distribution.  The full text of the license may be found at
   7 http://opensource.org/licenses/bsd-license.php
   8
   9 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11
  12 Module Name:
  13
  14   WatchDogTimer.c
  15
  16 Abstract:
  17
  18  Generic watchdog timer implemenetation using EFI APIs
  19
  20 Revision History
  21
  22 --*/
  23
  24 //
  25 // The package level header files this module uses
  26 //
  27 #include <PiDxe.h>
  28 #include <FrameworkDxe.h>
  29 //
  30 // The protocols, PPI and GUID defintions for this module
  31 //
  32 //
  33 // The Library classes this module consumes
  34 //
  35 #include <Library/DebugLib.h>
  36 #include <Library/UefiDriverEntryPoint.h>
  37 #include <Library/ReportStatusCodeLib.h>
  38 #include <Library/UefiBootServicesTableLib.h>
  39 #include <Library/UefiRuntimeServicesTableLib.h>
  40 #include <Protocol/WatchDogTimer.h>
  41
  42 #include "WatchDogTimer.h"
  43
  44 //
  45 // Handle for the Watchdog Timer Architectural Protocol instance produced by this driver
  46 //
  47 EFI_HANDLE                        mWatchdogTimerHandle = NULL;
  48
  49 //
  50 // The Watchdog Timer Architectural Protocol instance produced by this driver
  51 //
  52 EFI_WATCHDOG_TIMER_ARCH_PROTOCOL  mWatchdogTimer = {
  53   WatchdogTimerDriverRegisterHandler,
  54   WatchdogTimerDriverSetTimerPeriod,
  55   WatchdogTimerDriverGetTimerPeriod
  56 };
  57
  58 //
  59 // The watchdog timer period in 100 nS units
  60 //
  61 UINT64                            mWatchdogTimerPeriod = 0;
  62
  63 //
  64 // The notification function to call if the watchdig timer fires
  65 //
  66 EFI_WATCHDOG_TIMER_NOTIFY         mWatchdogTimerNotifyFunction = NULL;
  67
  68 //
  69 // The one-shot timer event that is armed when the watchdog timer is enabled
  70 //
  71 EFI_EVENT                         mWatchdogTimerEvent;
  72
  73 //
  74 // Worker Functions
  75 //
  76 STATIC
  77 VOID
  78 EFIAPI
  79 WatchdogTimerDriverExpires (
  80   IN EFI_EVENT    Timer,
  81   IN VOID         *Context
  82   )
  83 /*++
  84
  85   Routine Description:
  86
  87     Notification function that is called if the watchdog timer is fired.  If a
  88     handler has been registered with the Watchdog Timer Architectural Protocol,
  89     then that handler is called passing in the time period that has passed that
  90     cause the watchdog timer to fire.  Then, a call to the Runtime Service
  91     ResetSystem() is made to reset the platform.
  92
  93   Arguments:
  94
  95     Timer   - The one-shot timer event that was signaled when the watchdog timer
  96               expired.
  97
  98     Context - The context that was registered when the event Timer was created.
  99
 100   Returns:
 101
 102     None.
 103
 104 --*/
 105 {
 106   //
 107   // Report error code before exiting
 108   //
 109   REPORT_STATUS_CODE (
 110         EFI_ERROR_CODE | EFI_ERROR_MINOR,
 111         (EFI_COMPUTING_UNIT_HOST_PROCESSOR | EFI_CU_HP_EC_TIMER_EXPIRED)
 112         );
 113
 114   //
 115   // If a notification function has been registered, then call it
 116   //
 117   if (mWatchdogTimerNotifyFunction != NULL) {
 118     mWatchdogTimerNotifyFunction (mWatchdogTimerPeriod);
 119   }
 120   //
 121   // Reset the platform
 122   //
 123   gRT->ResetSystem (EfiResetCold, EFI_TIMEOUT, 0, NULL);
 124 }
 125
 126 EFI_STATUS
 127 EFIAPI
 128 WatchdogTimerDriverRegisterHandler (
 129   IN EFI_WATCHDOG_TIMER_ARCH_PROTOCOL  *This,
 130   IN EFI_WATCHDOG_TIMER_NOTIFY         NotifyFunction
 131   )
 132 /*++
 133
 134 Routine Description:
 135
 136   This function registers a handler that is to be invoked when the watchdog
 137   timer fires.  By default, the EFI_WATCHDOG_TIMER protocol will call the
 138   Runtime Service ResetSystem() when the watchdog timer fires.  If a
 139   NotifyFunction is registered, then the NotifyFunction will be called before
 140   the Runtime Service ResetSystem() is called.  If NotifyFunction is NULL, then
 141   the watchdog handler is unregistered.  If a watchdog handler is registered,
 142   then EFI_SUCCESS is returned.  If an attempt is made to register a handler
 143   when a handler is already registered, then EFI_ALREADY_STARTED is returned.
 144   If an attempt is made to uninstall a handler when a handler is not installed,
 145   then return EFI_INVALID_PARAMETER.
 146
 147 Arguments:
 148
 149   This           - The EFI_WATCHDOG_TIMER_ARCH_PROTOCOL instance.
 150
 151   NotifyFunction - The function to call when the watchdog timer fires.  If this
 152                    is NULL, then the handler will be unregistered.
 153
 154 Returns:
 155
 156   EFI_SUCCESS           - The watchdog timer handler was registered or
 157                           unregistered.
 158
 159   EFI_ALREADY_STARTED   - NotifyFunction is not NULL, and a handler is already
 160                           registered.
 161
 162   EFI_INVALID_PARAMETER - NotifyFunction is NULL, and a handler was not
 163                           previously registered.
 164
 165 --*/
 166 {
 167   if (NotifyFunction == NULL && mWatchdogTimerNotifyFunction == NULL) {
 168     return EFI_INVALID_PARAMETER;
 169   }
 170
 171   if (NotifyFunction != NULL && mWatchdogTimerNotifyFunction != NULL) {
 172     return EFI_ALREADY_STARTED;
 173   }
 174
 175   mWatchdogTimerNotifyFunction = NotifyFunction;
 176
 177   return EFI_SUCCESS;
 178 }
 179
 180 EFI_STATUS
 181 EFIAPI
 182 WatchdogTimerDriverSetTimerPeriod (
 183   IN EFI_WATCHDOG_TIMER_ARCH_PROTOCOL  *This,
 184   IN UINT64                            TimerPeriod
 185   )
 186 /*++
 187
 188 Routine Description:
 189
 190   This function sets the amount of time to wait before firing the watchdog
 191   timer to TimerPeriod 100 nS units.  If TimerPeriod is 0, then the watchdog
 192   timer is disabled.
 193
 194 Arguments:
 195
 196   This        - The EFI_WATCHDOG_TIMER_ARCH_PROTOCOL instance.
 197
 198   TimerPeriod - The amount of time in 100 nS units to wait before the watchdog
 199                 timer is fired.  If TimerPeriod is zero, then the watchdog
 200                 timer is disabled.
 201
 202 Returns:
 203
 204   EFI_SUCCESS      - The watchdog timer has been programmed to fire in Time
 205                      100 nS units.
 206
 207   EFI_DEVICE_ERROR - A watchdog timer could not be programmed due to a device
 208                      error.
 209
 210 --*/
 211 {
 212   mWatchdogTimerPeriod = TimerPeriod;
 213
 214   return gBS->SetTimer (
 215                 mWatchdogTimerEvent,
 216                 (mWatchdogTimerPeriod == 0) ? TimerCancel : TimerRelative,
 217                 mWatchdogTimerPeriod
 218                 );
 219 }
 220
 221 EFI_STATUS
 222 EFIAPI
 223 WatchdogTimerDriverGetTimerPeriod (
 224   IN EFI_WATCHDOG_TIMER_ARCH_PROTOCOL  *This,
 225   IN UINT64                            *TimerPeriod
 226   )
 227 /*++
 228
 229 Routine Description:
 230
 231   This function retrieves the amount of time the system will wait before firing
 232   the watchdog timer.  This period is returned in TimerPeriod, and EFI_SUCCESS
 233   is returned.  If TimerPeriod is NULL, then EFI_INVALID_PARAMETER is returned.
 234
 235 Arguments:
 236
 237   This        - The EFI_WATCHDOG_TIMER_ARCH_PROTOCOL instance.
 238
 239   TimerPeriod - A pointer to the amount of time in 100 nS units that the system
 240                 will wait before the watchdog timer is fired.  If TimerPeriod of
 241                 zero is returned, then the watchdog timer is disabled.
 242
 243 Returns:
 244
 245   EFI_SUCCESS           - The amount of time that the system will wait before
 246                           firing the watchdog timer was returned in TimerPeriod.
 247
 248   EFI_INVALID_PARAMETER - TimerPeriod is NULL.
 249
 250 --*/
 251 {
 252   if (TimerPeriod == NULL) {
 253     return EFI_INVALID_PARAMETER;
 254   }
 255
 256   *TimerPeriod = mWatchdogTimerPeriod;
 257
 258   return EFI_SUCCESS;
 259 }
 260
 261 EFI_STATUS
 262 EFIAPI
 263 WatchdogTimerDriverInitialize (
 264   IN EFI_HANDLE        ImageHandle,
 265   IN EFI_SYSTEM_TABLE  *SystemTable
 266   )
 267 /*++
 268
 269 Routine Description:
 270
 271   Initialize the Watchdog Timer Architectural Protocol driver
 272
 273 Arguments:
 274
 275   ImageHandle - ImageHandle of the loaded driver
 276
 277   SystemTable - Pointer to the System Table
 278
 279 Returns:
 280
 281   EFI_SUCCESS           - Timer Architectural Protocol created
 282
 283   EFI_OUT_OF_RESOURCES  - Not enough resources available to initialize driver.
 284
 285   EFI_DEVICE_ERROR      - A device error occured attempting to initialize the driver.
 286
 287 --*/
 288 {
 289   EFI_STATUS  Status;
 290
 291   REPORT_STATUS_CODE (
 292         EFI_PROGRESS_CODE,
 293         (EFI_COMPUTING_UNIT_HOST_PROCESSOR | EFI_SW_PC_INIT_BEGIN)
 294         );
 295   //
 296   // Make sure the Watchdog Timer Architectural Protocol is not already installed in the system
 297   //
 298   ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gEfiWatchdogTimerArchProtocolGuid);
 299
 300   //
 301   // Create the timer event used to implement a simple watchdog timer
 302   //
 303   Status = gBS->CreateEvent (
 304                   EVT_TIMER | EVT_NOTIFY_SIGNAL,
 305                   TPL_NOTIFY,
 306                   WatchdogTimerDriverExpires,
 307                   NULL,
 308                   &mWatchdogTimerEvent
 309                   );
 310   ASSERT_EFI_ERROR (Status);
 311
 312   //
 313   // Install the Watchdog Timer Arch Protocol onto a new handle
 314   //
 315   Status = gBS->InstallMultipleProtocolInterfaces (
 316                   &mWatchdogTimerHandle,
 317                   &gEfiWatchdogTimerArchProtocolGuid,
 318                   &mWatchdogTimer,
 319                   NULL
 320                   );
 321   ASSERT_EFI_ERROR (Status);
 322
 323   REPORT_STATUS_CODE (
 324         EFI_PROGRESS_CODE,
 325         (EFI_COMPUTING_UNIT_HOST_PROCESSOR | EFI_SW_PC_INIT_END)
 326         );
 327
 328   return Status;
 329 }