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
;
58 C Interrupt Handler calledin the interrupt context when Source interrupt is active.
60 @param Source Source of the interrupt. Hardware routing off a specific platform defines
62 @param SystemContext Pointer to system register context. Mostly used by debuggers and will
63 update the system context after the return from the interrupt if
64 modified. Don't change these values unless you know what you are doing
69 TimerInterruptHandler (
70 IN HARDWARE_INTERRUPT_SOURCE Source
,
71 IN EFI_SYSTEM_CONTEXT SystemContext
77 // DXE core uses this callback for the EFI timer tick. The DXE core uses locks
78 // that raise to TPL_HIGH and then restore back to current level. Thus we need
79 // to make sure TPL level is set to TPL_HIGH while we are handling the timer tick.
81 OriginalTPL
= gBS
->RaiseTPL (TPL_HIGH_LEVEL
);
83 if (mTimerPeriodicCallback
) {
84 mTimerPeriodicCallback(SystemContext
);
87 if (mTimerNotifyFunction
) {
88 mTimerNotifyFunction(mTimerPeriod
);
91 // Clear all timer interrupts
92 MmioWrite32(TISR
, TISR_CLEAR_ALL
);
94 // Poll interrupt status bits to ensure clearing
95 while ((MmioRead32(TISR
) & TISR_ALL_INTERRUPT_MASK
) != TISR_NO_INTERRUPTS_PENDING
);
97 gBS
->RestoreTPL (OriginalTPL
);
101 This function registers the handler NotifyFunction so it is called every time
102 the timer interrupt fires. It also passes the amount of time since the last
103 handler call to the NotifyFunction. If NotifyFunction is NULL, then the
104 handler is unregistered. If the handler is registered, then EFI_SUCCESS is
105 returned. If the CPU does not support registering a timer interrupt handler,
106 then EFI_UNSUPPORTED is returned. If an attempt is made to register a handler
107 when a handler is already registered, then EFI_ALREADY_STARTED is returned.
108 If an attempt is made to unregister a handler when a handler is not registered,
109 then EFI_INVALID_PARAMETER is returned. If an error occurs attempting to
110 register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR
113 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
114 @param NotifyFunction The function to call when a timer interrupt fires. This
115 function executes at TPL_HIGH_LEVEL. The DXE Core will
116 register a handler for the timer interrupt, so it can know
117 how much time has passed. This information is used to
118 signal timer based events. NULL will unregister the handler.
120 @retval EFI_SUCCESS The timer handler was registered.
121 @retval EFI_UNSUPPORTED The platform does not support timer interrupts.
122 @retval EFI_ALREADY_STARTED NotifyFunction is not NULL, and a handler is already
124 @retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not
125 previously registered.
126 @retval EFI_DEVICE_ERROR The timer handler could not be registered.
131 TimerDriverRegisterHandler (
132 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
133 IN EFI_TIMER_NOTIFY NotifyFunction
136 if ((NotifyFunction
== NULL
) && (mTimerNotifyFunction
== NULL
)) {
137 return EFI_INVALID_PARAMETER
;
140 if ((NotifyFunction
!= NULL
) && (mTimerNotifyFunction
!= NULL
)) {
141 return EFI_ALREADY_STARTED
;
144 mTimerNotifyFunction
= NotifyFunction
;
150 This function adjusts the period of timer interrupts to the value specified
151 by TimerPeriod. If the timer period is updated, then the selected timer
152 period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If
153 the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.
154 If an error occurs while attempting to update the timer period, then the
155 timer hardware will be put back in its state prior to this call, and
156 EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt
157 is disabled. This is not the same as disabling the CPU's interrupts.
158 Instead, it must either turn off the timer hardware, or it must adjust the
159 interrupt controller so that a CPU interrupt is not generated when the timer
162 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
163 @param TimerPeriod The rate to program the timer interrupt in 100 nS units. If
164 the timer hardware is not programmable, then EFI_UNSUPPORTED is
165 returned. If the timer is programmable, then the timer period
166 will be rounded up to the nearest timer period that is supported
167 by the timer hardware. If TimerPeriod is set to 0, then the
168 timer interrupts will be disabled.
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.
177 TimerDriverSetTimerPeriod (
178 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
179 IN UINT64 TimerPeriod
186 if (TimerPeriod
== 0) {
188 MmioWrite32(TCLR
, TCLR_ST_OFF
);
190 Status
= gInterrupt
->DisableInterruptSource(gInterrupt
, gVector
);
192 // Calculate required timer count
193 TimerCount
= DivU64x32(TimerPeriod
* 100, PcdGet32(PcdEmbeddedFdPerformanceCounterPeriodInNanoseconds
));
195 // Set GPTIMER3 Load register
196 LoadValue
= (INT32
) -TimerCount
;
197 MmioWrite32(TLDR
, LoadValue
);
198 MmioWrite32(TCRR
, LoadValue
);
200 // Enable Overflow interrupt
201 MmioWrite32(TIER
, TIER_TCAR_IT_DISABLE
| TIER_OVF_IT_ENABLE
| TIER_MAT_IT_DISABLE
);
203 // Turn on GPTIMER3, it will reload at overflow
204 MmioWrite32(TCLR
, TCLR_AR_AUTORELOAD
| TCLR_ST_ON
);
206 Status
= gInterrupt
->EnableInterruptSource(gInterrupt
, gVector
);
210 // Save the new timer period
212 mTimerPeriod
= TimerPeriod
;
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.
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.
227 @retval EFI_SUCCESS The timer period was returned in TimerPeriod.
228 @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.
233 TimerDriverGetTimerPeriod (
234 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
235 OUT UINT64
*TimerPeriod
238 if (TimerPeriod
== NULL
) {
239 return EFI_INVALID_PARAMETER
;
242 *TimerPeriod
= mTimerPeriod
;
247 This function generates a soft timer interrupt. If the platform does not support soft
248 timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.
249 If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()
250 service, then a soft timer interrupt will be generated. If the timer interrupt is
251 enabled when this service is called, then the registered handler will be invoked. The
252 registered handler should not be able to distinguish a hardware-generated timer
253 interrupt from a software-generated timer interrupt.
255 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
257 @retval EFI_SUCCESS The soft timer interrupt was generated.
258 @retval EFI_UNSUPPORTED The platform does not support the generation of soft timer interrupts.
263 TimerDriverGenerateSoftInterrupt (
264 IN EFI_TIMER_ARCH_PROTOCOL
*This
267 return EFI_UNSUPPORTED
;
273 TimerDriverRegisterPeriodicCallback (
274 IN TIMER_DEBUG_SUPPORT_PROTOCOL
*This
,
275 IN EFI_PERIODIC_CALLBACK PeriodicCallback
278 if ((PeriodicCallback
== NULL
) && (mTimerPeriodicCallback
== NULL
)) {
279 return EFI_INVALID_PARAMETER
;
282 if ((PeriodicCallback
!= NULL
) && (mTimerPeriodicCallback
!= NULL
)) {
283 return EFI_ALREADY_STARTED
;
286 mTimerPeriodicCallback
= PeriodicCallback
;
293 Interface stucture for the Timer Architectural Protocol.
295 @par Protocol Description:
296 This protocol provides the services to initialize a periodic timer
297 interrupt, and to register a handler that is called each time the timer
298 interrupt fires. It may also provide a service to adjust the rate of the
299 periodic timer interrupt. When a timer interrupt occurs, the handler is
300 passed the amount of time that has passed since the previous timer
303 @param RegisterHandler
304 Registers a handler that will be called each time the
305 timer interrupt fires. TimerPeriod defines the minimum
306 time between timer interrupts, so TimerPeriod will also
307 be the minimum time between calls to the registered
310 @param SetTimerPeriod
311 Sets the period of the timer interrupt in 100 nS units.
312 This function is optional, and may return EFI_UNSUPPORTED.
313 If this function is supported, then the timer period will
314 be rounded up to the nearest supported timer period.
316 @param GetTimerPeriod
317 Retrieves the period of the timer interrupt in 100 nS units.
319 @param GenerateSoftInterrupt
320 Generates a soft timer interrupt that simulates the firing of
321 the timer interrupt. This service can be used to invoke the
322 registered handler if the timer interrupt has been masked for
326 EFI_TIMER_ARCH_PROTOCOL gTimer
= {
327 TimerDriverRegisterHandler
,
328 TimerDriverSetTimerPeriod
,
329 TimerDriverGetTimerPeriod
,
330 TimerDriverGenerateSoftInterrupt
333 TIMER_DEBUG_SUPPORT_PROTOCOL gTimerDebugSupport
= {
334 TimerDriverRegisterPeriodicCallback
339 Initialize the state information for the Timer Architectural Protocol and
340 the Timer Debug support protocol that allows the debugger to break into a
343 @param ImageHandle of the loaded driver
344 @param SystemTable Pointer to the System Table
346 @retval EFI_SUCCESS Protocol registered
347 @retval EFI_OUT_OF_RESOURCES Cannot allocate protocol data structure
348 @retval EFI_DEVICE_ERROR Hardware problems
354 IN EFI_HANDLE ImageHandle
,
355 IN EFI_SYSTEM_TABLE
*SystemTable
358 EFI_HANDLE Handle
= NULL
;
360 UINT32 TimerBaseAddress
;
362 // Find the interrupt controller protocol. ASSERT if not found.
363 Status
= gBS
->LocateProtocol(&gHardwareInterruptProtocolGuid
, NULL
, (VOID
**)&gInterrupt
);
364 ASSERT_EFI_ERROR (Status
);
366 // Set up the timer registers
367 TimerBaseAddress
= TimerBase(FixedPcdGet32(PcdBeagleArchTimer
));
368 TISR
= TimerBaseAddress
+ GPTIMER_TISR
;
369 TCLR
= TimerBaseAddress
+ GPTIMER_TCLR
;
370 TLDR
= TimerBaseAddress
+ GPTIMER_TLDR
;
371 TCRR
= TimerBaseAddress
+ GPTIMER_TCRR
;
372 TIER
= TimerBaseAddress
+ GPTIMER_TIER
;
375 Status
= TimerDriverSetTimerPeriod(&gTimer
, 0);
376 ASSERT_EFI_ERROR (Status
);
378 // Install interrupt handler
379 gVector
= InterruptVectorForTimer(FixedPcdGet32(PcdBeagleArchTimer
));
380 Status
= gInterrupt
->RegisterInterruptSource(gInterrupt
, gVector
, TimerInterruptHandler
);
381 ASSERT_EFI_ERROR (Status
);
383 // Set up default timer
384 Status
= TimerDriverSetTimerPeriod(&gTimer
, FixedPcdGet32(PcdTimerPeriod
));
385 ASSERT_EFI_ERROR (Status
);
387 // Install the Timer Architectural Protocol onto a new handle
388 Status
= gBS
->InstallMultipleProtocolInterfaces(&Handle
,
389 &gEfiTimerArchProtocolGuid
, &gTimer
,
390 &gTimerDebugSupportProtocolGuid
, &gTimerDebugSupport
,
392 ASSERT_EFI_ERROR(Status
);