summaryrefslogtreecommitdiff
path: root/Omap35xxPkg/TimerDxe/Timer.c
blob: f43b24bd37b82ef073d24b0214e35725c71bf413 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
/** @file
  Template for Timer Architecture Protocol driver of the ARM flavor

  Copyright (c) 2008-2009, Apple Inc. All rights reserved.
  
  All rights reserved. This program and the accompanying materials                          
  are licensed and made available under the terms and conditions of the BSD License         
  which accompanies this distribution.  The full text of the license may be found at        
  http://opensource.org/licenses/bsd-license.php                                            

  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,                     
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.             

**/


#include <PiDxe.h>

#include <Library/BaseLib.h>
#include <Library/DebugLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/UefiLib.h>
#include <Library/PcdLib.h>
#include <Library/IoLib.h>
#include <Library/OmapLib.h>

#include <Protocol/Timer.h>
#include <Protocol/HardwareInterrupt.h>
#include <Protocol/TimerDebugSupport.h>

#include <Omap3530/Omap3530.h>


// The notification function to call on every timer interrupt.
volatile EFI_TIMER_NOTIFY      mTimerNotifyFunction   = (EFI_TIMER_NOTIFY)NULL;
volatile EFI_PERIODIC_CALLBACK mTimerPeriodicCallback = (EFI_PERIODIC_CALLBACK)NULL;


// The current period of the timer interrupt
volatile UINT64 mTimerPeriod = 0;

// Cached copy of the Hardware Interrupt protocol instance
EFI_HARDWARE_INTERRUPT_PROTOCOL *gInterrupt = NULL;

// Cached registers
volatile UINT32 TISR;
volatile UINT32 TCLR;
volatile UINT32 TLDR;
volatile UINT32 TCRR;
volatile UINT32 TIER;

// Cached interrupt vector
volatile UINTN  gVector;


/**
  C Interrupt Handler calledin the interrupt context when Source interrupt is active.

  @param Source         Source of the interrupt. Hardware routing off a specific platform defines
                        what source means.
  @param SystemContext  Pointer to system register context. Mostly used by debuggers and will
                        update the system context after the return from the interrupt if 
                        modified. Don't change these values unless you know what you are doing

**/
VOID
EFIAPI
TimerInterruptHandler (
  IN  HARDWARE_INTERRUPT_SOURCE   Source,
  IN  EFI_SYSTEM_CONTEXT          SystemContext       
  )
{
  EFI_TPL OriginalTPL;

  //
  // DXE core uses this callback for the EFI timer tick. The DXE core uses locks 
  // that raise to TPL_HIGH and then restore back to current level. Thus we need
  // to make sure TPL level is set to TPL_HIGH while we are handling the timer tick. 
  //
  OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);

  if (mTimerPeriodicCallback) {
    mTimerPeriodicCallback(SystemContext);
  }

  if (mTimerNotifyFunction) {
    mTimerNotifyFunction(mTimerPeriod);
  }

  // Clear all timer interrupts
  MmioWrite32(TISR, TISR_CLEAR_ALL);  

  // Poll interrupt status bits to ensure clearing
  while ((MmioRead32(TISR) & TISR_ALL_INTERRUPT_MASK) != TISR_NO_INTERRUPTS_PENDING);

  gBS->RestoreTPL (OriginalTPL);
}

/**
  This function registers the handler NotifyFunction so it is called every time 
  the timer interrupt fires.  It also passes the amount of time since the last 
  handler call to the NotifyFunction.  If NotifyFunction is NULL, then the 
  handler is unregistered.  If the handler is registered, then EFI_SUCCESS is 
  returned.  If the CPU does not support registering a timer interrupt handler, 
  then EFI_UNSUPPORTED is returned.  If an attempt is made to register a handler 
  when a handler is already registered, then EFI_ALREADY_STARTED is returned.  
  If an attempt is made to unregister a handler when a handler is not registered, 
  then EFI_INVALID_PARAMETER is returned.  If an error occurs attempting to 
  register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR 
  is returned.

  @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.
  @param  NotifyFunction   The function to call when a timer interrupt fires. This
                           function executes at TPL_HIGH_LEVEL. The DXE Core will
                           register a handler for the timer interrupt, so it can know
                           how much time has passed. This information is used to
                           signal timer based events. NULL will unregister the handler.

  @retval EFI_SUCCESS           The timer handler was registered.
  @retval EFI_UNSUPPORTED       The platform does not support timer interrupts.
  @retval EFI_ALREADY_STARTED   NotifyFunction is not NULL, and a handler is already
                                registered.
  @retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not
                                previously registered.
  @retval EFI_DEVICE_ERROR      The timer handler could not be registered.

**/
EFI_STATUS
EFIAPI
TimerDriverRegisterHandler (
  IN EFI_TIMER_ARCH_PROTOCOL  *This,
  IN EFI_TIMER_NOTIFY         NotifyFunction
  )
{
  if ((NotifyFunction == NULL) && (mTimerNotifyFunction == NULL)) {
    return EFI_INVALID_PARAMETER;
  }

  if ((NotifyFunction != NULL) && (mTimerNotifyFunction != NULL)) {
    return EFI_ALREADY_STARTED;
  }

  mTimerNotifyFunction = NotifyFunction;

  return EFI_SUCCESS;
}

/**
  This function adjusts the period of timer interrupts to the value specified 
  by TimerPeriod.  If the timer period is updated, then the selected timer 
  period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned.  If 
  the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.  
  If an error occurs while attempting to update the timer period, then the 
  timer hardware will be put back in its state prior to this call, and 
  EFI_DEVICE_ERROR is returned.  If TimerPeriod is 0, then the timer interrupt 
  is disabled.  This is not the same as disabling the CPU's interrupts.  
  Instead, it must either turn off the timer hardware, or it must adjust the 
  interrupt controller so that a CPU interrupt is not generated when the timer 
  interrupt fires. 

  @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.
  @param  TimerPeriod      The rate to program the timer interrupt in 100 nS units. If
                           the timer hardware is not programmable, then EFI_UNSUPPORTED is
                           returned. If the timer is programmable, then the timer period
                           will be rounded up to the nearest timer period that is supported
                           by the timer hardware. If TimerPeriod is set to 0, then the
                           timer interrupts will be disabled.

  @retval EFI_SUCCESS           The timer period was changed.
  @retval EFI_UNSUPPORTED       The platform cannot change the period of the timer interrupt.
  @retval EFI_DEVICE_ERROR      The timer period could not be changed due to a device error.

**/
EFI_STATUS
EFIAPI
TimerDriverSetTimerPeriod (
  IN EFI_TIMER_ARCH_PROTOCOL  *This,
  IN UINT64                   TimerPeriod
  )
{
  EFI_STATUS  Status;
  UINT64      TimerCount;
  INT32       LoadValue;
  
  if (TimerPeriod == 0) {
    // Turn off GPTIMER3
    MmioWrite32(TCLR, TCLR_ST_OFF);
    
    Status = gInterrupt->DisableInterruptSource(gInterrupt, gVector);    
  } else {  
    // Calculate required timer count
    TimerCount = DivU64x32(TimerPeriod * 100, PcdGet32(PcdEmbeddedFdPerformanceCounterPeriodInNanoseconds));

    // Set GPTIMER3 Load register
    LoadValue = (INT32) -TimerCount;
    MmioWrite32(TLDR, LoadValue);
    MmioWrite32(TCRR, LoadValue);

    // Enable Overflow interrupt
    MmioWrite32(TIER, TIER_TCAR_IT_DISABLE | TIER_OVF_IT_ENABLE | TIER_MAT_IT_DISABLE);

    // Turn on GPTIMER3, it will reload at overflow
    MmioWrite32(TCLR, TCLR_AR_AUTORELOAD | TCLR_ST_ON);

    Status = gInterrupt->EnableInterruptSource(gInterrupt, gVector);    
  }

  //
  // Save the new timer period
  //
  mTimerPeriod = TimerPeriod;
  return Status;
}


/**
  This function retrieves the period of timer interrupts in 100 ns units, 
  returns that value in TimerPeriod, and returns EFI_SUCCESS.  If TimerPeriod 
  is NULL, then EFI_INVALID_PARAMETER is returned.  If a TimerPeriod of 0 is 
  returned, then the timer is currently disabled.

  @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.
  @param  TimerPeriod      A pointer to the timer period to retrieve in 100 ns units. If
                           0 is returned, then the timer is currently disabled.

  @retval EFI_SUCCESS           The timer period was returned in TimerPeriod.
  @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.

**/
EFI_STATUS
EFIAPI
TimerDriverGetTimerPeriod (
  IN EFI_TIMER_ARCH_PROTOCOL   *This,
  OUT UINT64                   *TimerPeriod
  )
{
  if (TimerPeriod == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  *TimerPeriod = mTimerPeriod;
  return EFI_SUCCESS;
}

/**
  This function generates a soft timer interrupt. If the platform does not support soft 
  timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned. 
  If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler() 
  service, then a soft timer interrupt will be generated. If the timer interrupt is 
  enabled when this service is called, then the registered handler will be invoked. The 
  registered handler should not be able to distinguish a hardware-generated timer 
  interrupt from a software-generated timer interrupt.

  @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.

  @retval EFI_SUCCESS           The soft timer interrupt was generated.
  @retval EFI_UNSUPPORTED       The platform does not support the generation of soft timer interrupts.

**/
EFI_STATUS
EFIAPI
TimerDriverGenerateSoftInterrupt (
  IN EFI_TIMER_ARCH_PROTOCOL  *This
  )
{
  return EFI_UNSUPPORTED;
}


EFI_STATUS
EFIAPI
TimerDriverRegisterPeriodicCallback (
  IN  TIMER_DEBUG_SUPPORT_PROTOCOL  *This,
  IN  EFI_PERIODIC_CALLBACK         PeriodicCallback
  )
{
  if ((PeriodicCallback == NULL) && (mTimerPeriodicCallback == NULL)) {
    return EFI_INVALID_PARAMETER;
  }

  if ((PeriodicCallback != NULL) && (mTimerPeriodicCallback != NULL)) {
    return EFI_ALREADY_STARTED;
  }

  mTimerPeriodicCallback = PeriodicCallback;

  return EFI_SUCCESS;
}


/**
  Interface stucture for the Timer Architectural Protocol.

  @par Protocol Description:
  This protocol provides the services to initialize a periodic timer 
  interrupt, and to register a handler that is called each time the timer
  interrupt fires.  It may also provide a service to adjust the rate of the
  periodic timer interrupt.  When a timer interrupt occurs, the handler is 
  passed the amount of time that has passed since the previous timer 
  interrupt.

  @param RegisterHandler
  Registers a handler that will be called each time the 
  timer interrupt fires.  TimerPeriod defines the minimum 
  time between timer interrupts, so TimerPeriod will also 
  be the minimum time between calls to the registered 
  handler.

  @param SetTimerPeriod
  Sets the period of the timer interrupt in 100 nS units.  
  This function is optional, and may return EFI_UNSUPPORTED.  
  If this function is supported, then the timer period will 
  be rounded up to the nearest supported timer period.

  @param GetTimerPeriod
  Retrieves the period of the timer interrupt in 100 nS units.

  @param GenerateSoftInterrupt
  Generates a soft timer interrupt that simulates the firing of 
  the timer interrupt. This service can be used to invoke the 
  registered handler if the timer interrupt has been masked for 
  a period of time.

**/
EFI_TIMER_ARCH_PROTOCOL   gTimer = {
  TimerDriverRegisterHandler,
  TimerDriverSetTimerPeriod,
  TimerDriverGetTimerPeriod,
  TimerDriverGenerateSoftInterrupt
};

TIMER_DEBUG_SUPPORT_PROTOCOL  gTimerDebugSupport = {
  TimerDriverRegisterPeriodicCallback
};


/**
  Initialize the state information for the Timer Architectural Protocol and
  the Timer Debug support protocol that allows the debugger to break into a
  running program.

  @param  ImageHandle   of the loaded driver
  @param  SystemTable   Pointer to the System Table

  @retval EFI_SUCCESS           Protocol registered
  @retval EFI_OUT_OF_RESOURCES  Cannot allocate protocol data structure
  @retval EFI_DEVICE_ERROR      Hardware problems

**/
EFI_STATUS
EFIAPI
TimerInitialize (
  IN EFI_HANDLE         ImageHandle,
  IN EFI_SYSTEM_TABLE   *SystemTable
  )
{
  EFI_HANDLE  Handle = NULL;
  EFI_STATUS  Status;
  UINT32      TimerBaseAddress;

  // Find the interrupt controller protocol.  ASSERT if not found.
  Status = gBS->LocateProtocol(&gHardwareInterruptProtocolGuid, NULL, (VOID **)&gInterrupt);
  ASSERT_EFI_ERROR (Status);

  // Set up the timer registers
  TimerBaseAddress = TimerBase(FixedPcdGet32(PcdBeagleArchTimer));
  TISR = TimerBaseAddress + GPTIMER_TISR;
  TCLR = TimerBaseAddress + GPTIMER_TCLR;
  TLDR = TimerBaseAddress + GPTIMER_TLDR;
  TCRR = TimerBaseAddress + GPTIMER_TCRR;
  TIER = TimerBaseAddress + GPTIMER_TIER;

  // Disable the timer
  Status = TimerDriverSetTimerPeriod(&gTimer, 0);
  ASSERT_EFI_ERROR (Status);

  // Install interrupt handler
  gVector = InterruptVectorForTimer(FixedPcdGet32(PcdBeagleArchTimer));
  Status = gInterrupt->RegisterInterruptSource(gInterrupt, gVector, TimerInterruptHandler);
  ASSERT_EFI_ERROR (Status);

  // Set up default timer
  Status = TimerDriverSetTimerPeriod(&gTimer, FixedPcdGet32(PcdTimerPeriod));
  ASSERT_EFI_ERROR (Status);

  // Install the Timer Architectural Protocol onto a new handle
  Status = gBS->InstallMultipleProtocolInterfaces(&Handle,
                                                  &gEfiTimerArchProtocolGuid,      &gTimer,
                                                  &gTimerDebugSupportProtocolGuid, &gTimerDebugSupport,
                                                  NULL);
  ASSERT_EFI_ERROR(Status);

  return Status;
}