2 Template for Timer Architecture Protocol driver of the ARM flavor
4 Copyright (c) 2008-2009, Apple Inc. All rights reserved.
6 All rights reserved. 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
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.
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>
28 #include <Protocol/Timer.h>
29 #include <Protocol/HardwareInterrupt.h>
30 #include <Protocol/TimerDebugSupport.h>
32 #include <Omap3530/Omap3530.h>
35 // The notification function to call on every timer interrupt.
36 volatile EFI_TIMER_NOTIFY mTimerNotifyFunction
= (EFI_TIMER_NOTIFY
)NULL
;
37 volatile EFI_PERIODIC_CALLBACK mTimerPeriodicCallback
= (EFI_PERIODIC_CALLBACK
)NULL
;
40 // The current period of the timer interrupt
41 volatile UINT64 mTimerPeriod
= 0;
43 // Cached copy of the Hardware Interrupt protocol instance
44 EFI_HARDWARE_INTERRUPT_PROTOCOL
*gInterrupt
= NULL
;
53 // Cached interrupt vector
54 volatile UINTN gVector
;
59 C Interrupt Handler calledin the interrupt context when Source interrupt is active.
62 @param Source Source of the interrupt. Hardware routing off a specific platform defines
65 @param SystemContext Pointer to system register context. Mostly used by debuggers and will
66 update the system context after the return from the interrupt if
67 modified. Don't change these values unless you know what you are doing
72 TimerInterruptHandler (
73 IN HARDWARE_INTERRUPT_SOURCE Source
,
74 IN EFI_SYSTEM_CONTEXT SystemContext
82 // DXE core uses this callback for the EFI timer tick. The DXE core uses locks
83 // that raise to TPL_HIGH and then restore back to current level. Thus we need
84 // to make sure TPL level is set to TPL_HIGH while we are handling the timer tick.
86 OriginalTPL
= gBS
->RaiseTPL (TPL_HIGH_LEVEL
);
89 if (mTimerPeriodicCallback
) {
90 mTimerPeriodicCallback(SystemContext
);
93 if (mTimerNotifyFunction
) {
94 mTimerNotifyFunction(mTimerPeriod
);
97 // Clear all timer interrupts
98 MmioWrite32 (TISR
, TISR_CLEAR_ALL
);
100 // Poll interrupt status bits to ensure clearing
101 while ((MmioRead32(TISR
) & TISR_ALL_INTERRUPT_MASK
) != TISR_NO_INTERRUPTS_PENDING
);
103 gBS
->RestoreTPL (OriginalTPL
);
107 This function registers the handler NotifyFunction so it is called every time
108 the timer interrupt fires. It also passes the amount of time since the last
109 handler call to the NotifyFunction. If NotifyFunction is NULL, then the
110 handler is unregistered. If the handler is registered, then EFI_SUCCESS is
111 returned. If the CPU does not support registering a timer interrupt handler,
112 then EFI_UNSUPPORTED is returned. If an attempt is made to register a handler
113 when a handler is already registered, then EFI_ALREADY_STARTED is returned.
114 If an attempt is made to unregister a handler when a handler is not registered,
115 then EFI_INVALID_PARAMETER is returned. If an error occurs attempting to
116 register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR
119 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
120 @param NotifyFunction The function to call when a timer interrupt fires. This
121 function executes at TPL_HIGH_LEVEL. The DXE Core will
122 register a handler for the timer interrupt, so it can know
123 how much time has passed. This information is used to
124 signal timer based events. NULL will unregister the handler.
125 @retval EFI_SUCCESS The timer handler was registered.
126 @retval EFI_UNSUPPORTED The platform does not support timer interrupts.
127 @retval EFI_ALREADY_STARTED NotifyFunction is not NULL, and a handler is already
129 @retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not
130 previously registered.
131 @retval EFI_DEVICE_ERROR The timer handler could not be registered.
136 TimerDriverRegisterHandler (
137 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
138 IN EFI_TIMER_NOTIFY NotifyFunction
141 if ((NotifyFunction
== NULL
) && (mTimerNotifyFunction
== NULL
)) {
142 return EFI_INVALID_PARAMETER
;
145 if ((NotifyFunction
!= NULL
) && (mTimerNotifyFunction
!= NULL
)) {
146 return EFI_ALREADY_STARTED
;
149 mTimerNotifyFunction
= NotifyFunction
;
156 This function adjusts the period of timer interrupts to the value specified
157 by TimerPeriod. If the timer period is updated, then the selected timer
158 period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If
159 the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.
160 If an error occurs while attempting to update the timer period, then the
161 timer hardware will be put back in its state prior to this call, and
162 EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt
163 is disabled. This is not the same as disabling the CPU's interrupts.
164 Instead, it must either turn off the timer hardware, or it must adjust the
165 interrupt controller so that a CPU interrupt is not generated when the timer
168 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
169 @param TimerPeriod The rate to program the timer interrupt in 100 nS units. If
170 the timer hardware is not programmable, then EFI_UNSUPPORTED is
171 returned. If the timer is programmable, then the timer period
172 will be rounded up to the nearest timer period that is supported
173 by the timer hardware. If TimerPeriod is set to 0, then the
174 timer interrupts will be disabled.
177 @retval EFI_SUCCESS The timer period was changed.
178 @retval EFI_UNSUPPORTED The platform cannot change the period of the timer interrupt.
179 @retval EFI_DEVICE_ERROR The timer period could not be changed due to a device error.
184 TimerDriverSetTimerPeriod (
185 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
186 IN UINT64 TimerPeriod
193 if (TimerPeriod
== 0) {
195 MmioWrite32 (TCLR
, TCLR_ST_OFF
);
197 Status
= gInterrupt
->DisableInterruptSource(gInterrupt
, gVector
);
199 // Calculate required timer count
200 TimerCount
= DivU64x32(TimerPeriod
* 100, PcdGet32(PcdEmbeddedFdPerformanceCounterPeriodInNanoseconds
));
202 // Set GPTIMER3 Load register
203 LoadValue
= (INT32
) -TimerCount
;
204 MmioWrite32 (TLDR
, LoadValue
);
205 MmioWrite32 (TCRR
, LoadValue
);
207 // Enable Overflow interrupt
208 MmioWrite32 (TIER
, TIER_TCAR_IT_DISABLE
| TIER_OVF_IT_ENABLE
| TIER_MAT_IT_DISABLE
);
210 // Turn on GPTIMER3, it will reload at overflow
211 MmioWrite32 (TCLR
, TCLR_AR_AUTORELOAD
| TCLR_ST_ON
);
213 Status
= gInterrupt
->EnableInterruptSource(gInterrupt
, gVector
);
217 // Save the new timer period
219 mTimerPeriod
= TimerPeriod
;
225 This function retrieves the period of timer interrupts in 100 ns units,
226 returns that value in TimerPeriod, and returns EFI_SUCCESS. If TimerPeriod
227 is NULL, then EFI_INVALID_PARAMETER is returned. If a TimerPeriod of 0 is
228 returned, then the timer is currently disabled.
230 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
231 @param TimerPeriod A pointer to the timer period to retrieve in 100 ns units. If
232 0 is returned, then the timer is currently disabled.
235 @retval EFI_SUCCESS The timer period was returned in TimerPeriod.
236 @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.
241 TimerDriverGetTimerPeriod (
242 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
243 OUT UINT64
*TimerPeriod
246 if (TimerPeriod
== NULL
) {
247 return EFI_INVALID_PARAMETER
;
250 *TimerPeriod
= mTimerPeriod
;
255 This function generates a soft timer interrupt. If the platform does not support soft
256 timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.
257 If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()
258 service, then a soft timer interrupt will be generated. If the timer interrupt is
259 enabled when this service is called, then the registered handler will be invoked. The
260 registered handler should not be able to distinguish a hardware-generated timer
261 interrupt from a software-generated timer interrupt.
263 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
265 @retval EFI_SUCCESS The soft timer interrupt was generated.
266 @retval EFI_UNSUPPORTED The platform does not support the generation of soft timer interrupts.
271 TimerDriverGenerateSoftInterrupt (
272 IN EFI_TIMER_ARCH_PROTOCOL
*This
275 return EFI_UNSUPPORTED
;
281 TimerDriverRegisterPeriodicCallback (
282 IN TIMER_DEBUG_SUPPORT_PROTOCOL
*This
,
283 IN EFI_PERIODIC_CALLBACK PeriodicCallback
286 if ((PeriodicCallback
== NULL
) && (mTimerPeriodicCallback
== NULL
)) {
287 return EFI_INVALID_PARAMETER
;
290 if ((PeriodicCallback
!= NULL
) && (mTimerPeriodicCallback
!= NULL
)) {
291 return EFI_ALREADY_STARTED
;
294 mTimerPeriodicCallback
= PeriodicCallback
;
301 Interface stucture for the Timer Architectural Protocol.
303 @par Protocol Description:
304 This protocol provides the services to initialize a periodic timer
305 interrupt, and to register a handler that is called each time the timer
306 interrupt fires. It may also provide a service to adjust the rate of the
307 periodic timer interrupt. When a timer interrupt occurs, the handler is
308 passed the amount of time that has passed since the previous timer
311 @param RegisterHandler
312 Registers a handler that will be called each time the
313 timer interrupt fires. TimerPeriod defines the minimum
314 time between timer interrupts, so TimerPeriod will also
315 be the minimum time between calls to the registered
318 @param SetTimerPeriod
319 Sets the period of the timer interrupt in 100 nS units.
320 This function is optional, and may return EFI_UNSUPPORTED.
321 If this function is supported, then the timer period will
322 be rounded up to the nearest supported timer period.
325 @param GetTimerPeriod
326 Retrieves the period of the timer interrupt in 100 nS units.
328 @param GenerateSoftInterrupt
329 Generates a soft timer interrupt that simulates the firing of
330 the timer interrupt. This service can be used to invoke the registered handler if the timer interrupt has been masked for
334 EFI_TIMER_ARCH_PROTOCOL gTimer
= {
335 TimerDriverRegisterHandler
,
336 TimerDriverSetTimerPeriod
,
337 TimerDriverGetTimerPeriod
,
338 TimerDriverGenerateSoftInterrupt
341 TIMER_DEBUG_SUPPORT_PROTOCOL gTimerDebugSupport
= {
342 TimerDriverRegisterPeriodicCallback
347 Initialize the state information for the Timer Architectural Protocol and
348 the Timer Debug support protocol that allows the debugger to break into a
351 @param ImageHandle of the loaded driver
352 @param SystemTable Pointer to the System Table
354 @retval EFI_SUCCESS Protocol registered
355 @retval EFI_OUT_OF_RESOURCES Cannot allocate protocol data structure
356 @retval EFI_DEVICE_ERROR Hardware problems
362 IN EFI_HANDLE ImageHandle
,
363 IN EFI_SYSTEM_TABLE
*SystemTable
366 EFI_HANDLE Handle
= NULL
;
368 UINT32 TimerBaseAddress
;
370 // Find the interrupt controller protocol. ASSERT if not found.
371 Status
= gBS
->LocateProtocol(&gHardwareInterruptProtocolGuid
, NULL
, (VOID
**)&gInterrupt
);
372 ASSERT_EFI_ERROR (Status
);
374 // Set up the timer registers
375 TimerBaseAddress
= TimerBase(FixedPcdGet32(PcdBeagleArchTimer
));
376 TISR
= TimerBaseAddress
+ GPTIMER_TISR
;
377 TCLR
= TimerBaseAddress
+ GPTIMER_TCLR
;
378 TLDR
= TimerBaseAddress
+ GPTIMER_TLDR
;
379 TCRR
= TimerBaseAddress
+ GPTIMER_TCRR
;
380 TIER
= TimerBaseAddress
+ GPTIMER_TIER
;
383 Status
= TimerDriverSetTimerPeriod(&gTimer
, 0);
384 ASSERT_EFI_ERROR (Status
);
386 // Install interrupt handler
387 gVector
= InterruptVectorForTimer(FixedPcdGet32(PcdBeagleArchTimer
));
388 Status
= gInterrupt
->RegisterInterruptSource(gInterrupt
, gVector
, TimerInterruptHandler
);
389 ASSERT_EFI_ERROR (Status
);
391 // Set up default timer
392 Status
= TimerDriverSetTimerPeriod(&gTimer
, FixedPcdGet32(PcdTimerPeriod
));
393 ASSERT_EFI_ERROR (Status
);
395 // Install the Timer Architectural Protocol onto a new handle
396 Status
= gBS
->InstallMultipleProtocolInterfaces(&Handle
,
397 &gEfiTimerArchProtocolGuid
, &gTimer
,
398 &gTimerDebugSupportProtocolGuid
, &gTimerDebugSupport
,
400 ASSERT_EFI_ERROR(Status
);