2 Template for Timer Architecture Protocol driver of the ARM flavor
4 Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
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
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>
27 #include <Protocol/Timer.h>
28 #include <Protocol/HardwareInterrupt.h>
30 #include <Drivers/SP804Timer.h>
31 #include <ArmPlatform.h>
33 // The notification function to call on every timer interrupt.
34 volatile EFI_TIMER_NOTIFY mTimerNotifyFunction
= (EFI_TIMER_NOTIFY
)NULL
;
35 EFI_EVENT EfiExitBootServicesEvent
= (EFI_EVENT
)NULL
;
37 // The current period of the timer interrupt
38 volatile UINT64 mTimerPeriod
= 0;
40 // Cached copy of the Hardware Interrupt protocol instance
41 EFI_HARDWARE_INTERRUPT_PROTOCOL
*gInterrupt
= NULL
;
43 // Cached interrupt vector
46 UINT32 mLastTickCount
;
50 C Interrupt Handler called in the interrupt context when Source interrupt is active.
53 @param Source Source of the interrupt. Hardware routing off a specific platform defines
56 @param SystemContext Pointer to system register context. Mostly used by debuggers and will
57 update the system context after the return from the interrupt if
58 modified. Don't change these values unless you know what you are doing
63 TimerInterruptHandler (
64 IN HARDWARE_INTERRUPT_SOURCE Source
,
65 IN EFI_SYSTEM_CONTEXT SystemContext
71 // DXE core uses this callback for the EFI timer tick. The DXE core uses locks
72 // that raise to TPL_HIGH and then restore back to current level. Thus we need
73 // to make sure TPL level is set to TPL_HIGH while we are handling the timer tick.
75 OriginalTPL
= gBS
->RaiseTPL (TPL_HIGH_LEVEL
);
77 // If the interrupt is shared then we must check if this interrupt source is the one associated to this Timer
78 if (MmioRead32 (SP804_TIMER0_BASE
+ SP804_TIMER_MSK_INT_STS_REG
) != 0) {
79 // clear the periodic interrupt
80 MmioWrite32 (SP804_TIMER0_BASE
+ SP804_TIMER_INT_CLR_REG
, 0);
82 // signal end of interrupt early to help avoid losing subsequent ticks from long duration handlers
83 gInterrupt
->EndOfInterrupt (gInterrupt
, Source
);
85 if (mTimerNotifyFunction
) {
86 mTimerNotifyFunction (mTimerPeriod
);
90 gBS
->RestoreTPL (OriginalTPL
);
94 This function registers the handler NotifyFunction so it is called every time
95 the timer interrupt fires. It also passes the amount of time since the last
96 handler call to the NotifyFunction. If NotifyFunction is NULL, then the
97 handler is unregistered. If the handler is registered, then EFI_SUCCESS is
98 returned. If the CPU does not support registering a timer interrupt handler,
99 then EFI_UNSUPPORTED is returned. If an attempt is made to register a handler
100 when a handler is already registered, then EFI_ALREADY_STARTED is returned.
101 If an attempt is made to unregister a handler when a handler is not registered,
102 then EFI_INVALID_PARAMETER is returned. If an error occurs attempting to
103 register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR
106 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
107 @param NotifyFunction The function to call when a timer interrupt fires. This
108 function executes at TPL_HIGH_LEVEL. The DXE Core will
109 register a handler for the timer interrupt, so it can know
110 how much time has passed. This information is used to
111 signal timer based events. NULL will unregister the handler.
112 @retval EFI_SUCCESS The timer handler was registered.
113 @retval EFI_UNSUPPORTED The platform does not support timer interrupts.
114 @retval EFI_ALREADY_STARTED NotifyFunction is not NULL, and a handler is already
116 @retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not
117 previously registered.
118 @retval EFI_DEVICE_ERROR The timer handler could not be registered.
123 TimerDriverRegisterHandler (
124 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
125 IN EFI_TIMER_NOTIFY NotifyFunction
128 if ((NotifyFunction
== NULL
) && (mTimerNotifyFunction
== NULL
)) {
129 return EFI_INVALID_PARAMETER
;
132 if ((NotifyFunction
!= NULL
) && (mTimerNotifyFunction
!= NULL
)) {
133 return EFI_ALREADY_STARTED
;
136 mTimerNotifyFunction
= NotifyFunction
;
142 Make sure all ArrmVe Timers are disabled
146 ExitBootServicesEvent (
151 // Disable timer 0 if enabled
152 if (MmioRead32(SP804_TIMER0_BASE
+ SP804_TIMER_CONTROL_REG
) & SP804_TIMER_CTRL_ENABLE
) {
153 MmioAnd32 (SP804_TIMER0_BASE
+ SP804_TIMER_CONTROL_REG
, 0);
156 // Disable timer 1 if enabled
157 if (MmioRead32(SP804_TIMER1_BASE
+ SP804_TIMER_CONTROL_REG
) & SP804_TIMER_CTRL_ENABLE
) {
158 MmioAnd32 (SP804_TIMER1_BASE
+ SP804_TIMER_CONTROL_REG
, 0);
161 // Disable timer 2 if enabled
162 if (MmioRead32(SP804_TIMER2_BASE
+ SP804_TIMER_CONTROL_REG
) & SP804_TIMER_CTRL_ENABLE
) {
163 MmioAnd32 (SP804_TIMER2_BASE
+ SP804_TIMER_CONTROL_REG
, 0);
166 // Disable timer 3 if enabled
167 if (MmioRead32(SP804_TIMER3_BASE
+ SP804_TIMER_CONTROL_REG
) & SP804_TIMER_CTRL_ENABLE
) {
168 MmioAnd32 (SP804_TIMER3_BASE
+ SP804_TIMER_CONTROL_REG
, 0);
174 This function adjusts the period of timer interrupts to the value specified
175 by TimerPeriod. If the timer period is updated, then the selected timer
176 period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If
177 the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.
178 If an error occurs while attempting to update the timer period, then the
179 timer hardware will be put back in its state prior to this call, and
180 EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt
181 is disabled. This is not the same as disabling the CPU's interrupts.
182 Instead, it must either turn off the timer hardware, or it must adjust the
183 interrupt controller so that a CPU interrupt is not generated when the timer
186 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
187 @param TimerPeriod The rate to program the timer interrupt in 100 nS units. If
188 the timer hardware is not programmable, then EFI_UNSUPPORTED is
189 returned. If the timer is programmable, then the timer period
190 will be rounded up to the nearest timer period that is supported
191 by the timer hardware. If TimerPeriod is set to 0, then the
192 timer interrupts will be disabled.
195 @retval EFI_SUCCESS The timer period was changed.
196 @retval EFI_UNSUPPORTED The platform cannot change the period of the timer interrupt.
197 @retval EFI_DEVICE_ERROR The timer period could not be changed due to a device error.
202 TimerDriverSetTimerPeriod (
203 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
204 IN UINT64 TimerPeriod
210 // always disable the timer
211 MmioAnd32 (SP804_TIMER0_BASE
+ SP804_TIMER_CONTROL_REG
, ~SP804_TIMER_CTRL_ENABLE
);
213 if (TimerPeriod
== 0) {
214 // Leave timer disabled from above, and...
216 // Disable timer 0/1 interrupt for a TimerPeriod of 0
217 Status
= gInterrupt
->DisableInterruptSource (gInterrupt
, gVector
);
219 // Convert TimerPeriod into 1MHz clock counts (us units = 100ns units / 10)
220 TimerTicks
= DivU64x32 (TimerPeriod
, 10);
221 TimerTicks
= MultU64x32 (TimerTicks
, PcdGet32(PcdSP804FrequencyInMHz
));
223 // if it's larger than 32-bits, pin to highest value
224 if (TimerTicks
> 0xffffffff) {
226 TimerTicks
= 0xffffffff;
230 // Program the SP804 timer with the new count value
231 MmioWrite32 (SP804_TIMER0_BASE
+ SP804_TIMER_LOAD_REG
, TimerTicks
);
234 MmioOr32 (SP804_TIMER0_BASE
+ SP804_TIMER_CONTROL_REG
, SP804_TIMER_CTRL_ENABLE
);
236 // enable timer 0/1 interrupts
237 Status
= gInterrupt
->EnableInterruptSource (gInterrupt
, gVector
);
240 // Save the new timer period
241 mTimerPeriod
= TimerPeriod
;
246 This function retrieves the period of timer interrupts in 100 ns units,
247 returns that value in TimerPeriod, and returns EFI_SUCCESS. If TimerPeriod
248 is NULL, then EFI_INVALID_PARAMETER is returned. If a TimerPeriod of 0 is
249 returned, then the timer is currently disabled.
251 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
252 @param TimerPeriod A pointer to the timer period to retrieve in 100 ns units. If
253 0 is returned, then the timer is currently disabled.
256 @retval EFI_SUCCESS The timer period was returned in TimerPeriod.
257 @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.
262 TimerDriverGetTimerPeriod (
263 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
264 OUT UINT64
*TimerPeriod
267 if (TimerPeriod
== NULL
) {
268 return EFI_INVALID_PARAMETER
;
271 *TimerPeriod
= mTimerPeriod
;
276 This function generates a soft timer interrupt. If the platform does not support soft
277 timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.
278 If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()
279 service, then a soft timer interrupt will be generated. If the timer interrupt is
280 enabled when this service is called, then the registered handler will be invoked. The
281 registered handler should not be able to distinguish a hardware-generated timer
282 interrupt from a software-generated timer interrupt.
284 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
286 @retval EFI_SUCCESS The soft timer interrupt was generated.
287 @retval EFI_UNSUPPORTED The platform does not support the generation of soft timer interrupts.
292 TimerDriverGenerateSoftInterrupt (
293 IN EFI_TIMER_ARCH_PROTOCOL
*This
296 return EFI_UNSUPPORTED
;
300 Interface structure for the Timer Architectural Protocol.
302 @par Protocol Description:
303 This protocol provides the services to initialize a periodic timer
304 interrupt, and to register a handler that is called each time the timer
305 interrupt fires. It may also provide a service to adjust the rate of the
306 periodic timer interrupt. When a timer interrupt occurs, the handler is
307 passed the amount of time that has passed since the previous timer
310 @param RegisterHandler
311 Registers a handler that will be called each time the
312 timer interrupt fires. TimerPeriod defines the minimum
313 time between timer interrupts, so TimerPeriod will also
314 be the minimum time between calls to the registered
317 @param SetTimerPeriod
318 Sets the period of the timer interrupt in 100 nS units.
319 This function is optional, and may return EFI_UNSUPPORTED.
320 If this function is supported, then the timer period will
321 be rounded up to the nearest supported timer period.
324 @param GetTimerPeriod
325 Retrieves the period of the timer interrupt in 100 nS units.
327 @param GenerateSoftInterrupt
328 Generates a soft timer interrupt that simulates the firing of
329 the timer interrupt. This service can be used to invoke the registered handler if the timer interrupt has been masked for
333 EFI_TIMER_ARCH_PROTOCOL gTimer
= {
334 TimerDriverRegisterHandler
,
335 TimerDriverSetTimerPeriod
,
336 TimerDriverGetTimerPeriod
,
337 TimerDriverGenerateSoftInterrupt
342 Initialize the state information for the Timer Architectural Protocol and
343 the Timer Debug support protocol that allows the debugger to break into a
346 @param ImageHandle of the loaded driver
347 @param SystemTable Pointer to the System Table
349 @retval EFI_SUCCESS Protocol registered
350 @retval EFI_OUT_OF_RESOURCES Cannot allocate protocol data structure
351 @retval EFI_DEVICE_ERROR Hardware problems
357 IN EFI_HANDLE ImageHandle
,
358 IN EFI_SYSTEM_TABLE
*SystemTable
361 EFI_HANDLE Handle
= NULL
;
364 // Find the interrupt controller protocol. ASSERT if not found.
365 Status
= gBS
->LocateProtocol (&gHardwareInterruptProtocolGuid
, NULL
, (VOID
**)&gInterrupt
);
366 ASSERT_EFI_ERROR (Status
);
368 // Configure timer 1 for free running operation, 32 bits, no prescaler, interrupt disabled
369 MmioWrite32 (SP804_TIMER1_BASE
+ SP804_TIMER_CONTROL_REG
, SP804_TIMER_CTRL_32BIT
| SP804_PRESCALE_DIV_1
);
371 // Enable the free running timer
372 MmioOr32 (SP804_TIMER1_BASE
+ SP804_TIMER_CONTROL_REG
, SP804_TIMER_CTRL_ENABLE
);
374 // Record free running tick value (should be close to 0xffffffff)
375 mLastTickCount
= MmioRead32 (SP804_TIMER1_BASE
+ SP804_TIMER_CURRENT_REG
);
378 Status
= TimerDriverSetTimerPeriod (&gTimer
, 0);
379 ASSERT_EFI_ERROR (Status
);
381 // Install interrupt handler
382 gVector
= PcdGet32(PcdSP804Timer0InterruptNum
);
383 Status
= gInterrupt
->RegisterInterruptSource (gInterrupt
, gVector
, TimerInterruptHandler
);
384 ASSERT_EFI_ERROR (Status
);
386 // configure timer 0 for periodic operation, 32 bits, no prescaler, and interrupt enabled
387 MmioWrite32 (SP804_TIMER0_BASE
+ SP804_TIMER_CONTROL_REG
, SP804_TIMER_CTRL_PERIODIC
| SP804_TIMER_CTRL_32BIT
| SP804_PRESCALE_DIV_1
| SP804_TIMER_CTRL_INT_ENABLE
);
389 // Set up default timer
390 Status
= TimerDriverSetTimerPeriod (&gTimer
, FixedPcdGet32(PcdTimerPeriod
)); // TIMER_DEFAULT_PERIOD
391 ASSERT_EFI_ERROR (Status
);
393 // Install the Timer Architectural Protocol onto a new handle
394 Status
= gBS
->InstallMultipleProtocolInterfaces(
396 &gEfiTimerArchProtocolGuid
, &gTimer
,
399 ASSERT_EFI_ERROR(Status
);
401 // Register for an ExitBootServicesEvent
402 Status
= gBS
->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES
, TPL_NOTIFY
, ExitBootServicesEvent
, NULL
, &EfiExitBootServicesEvent
);
403 ASSERT_EFI_ERROR (Status
);