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 // clear the periodic interrupt
79 MmioWrite32 (SP804_TIMER0_BASE
+ SP804_TIMER_INT_CLR_REG
, 0);
81 // signal end of interrupt early to help avoid losing subsequent ticks from long duration handlers
82 gInterrupt
->EndOfInterrupt (gInterrupt
, Source
);
84 if (mTimerNotifyFunction
) {
85 mTimerNotifyFunction (mTimerPeriod
);
88 gBS
->RestoreTPL (OriginalTPL
);
92 This function registers the handler NotifyFunction so it is called every time
93 the timer interrupt fires. It also passes the amount of time since the last
94 handler call to the NotifyFunction. If NotifyFunction is NULL, then the
95 handler is unregistered. If the handler is registered, then EFI_SUCCESS is
96 returned. If the CPU does not support registering a timer interrupt handler,
97 then EFI_UNSUPPORTED is returned. If an attempt is made to register a handler
98 when a handler is already registered, then EFI_ALREADY_STARTED is returned.
99 If an attempt is made to unregister a handler when a handler is not registered,
100 then EFI_INVALID_PARAMETER is returned. If an error occurs attempting to
101 register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR
104 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
105 @param NotifyFunction The function to call when a timer interrupt fires. This
106 function executes at TPL_HIGH_LEVEL. The DXE Core will
107 register a handler for the timer interrupt, so it can know
108 how much time has passed. This information is used to
109 signal timer based events. NULL will unregister the handler.
110 @retval EFI_SUCCESS The timer handler was registered.
111 @retval EFI_UNSUPPORTED The platform does not support timer interrupts.
112 @retval EFI_ALREADY_STARTED NotifyFunction is not NULL, and a handler is already
114 @retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not
115 previously registered.
116 @retval EFI_DEVICE_ERROR The timer handler could not be registered.
121 TimerDriverRegisterHandler (
122 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
123 IN EFI_TIMER_NOTIFY NotifyFunction
126 if ((NotifyFunction
== NULL
) && (mTimerNotifyFunction
== NULL
)) {
127 return EFI_INVALID_PARAMETER
;
130 if ((NotifyFunction
!= NULL
) && (mTimerNotifyFunction
!= NULL
)) {
131 return EFI_ALREADY_STARTED
;
134 mTimerNotifyFunction
= NotifyFunction
;
140 Make sure all ArrmVe Timers are disabled
144 ExitBootServicesEvent (
149 // Disable timer 0 if enabled
150 if (MmioRead32(SP804_TIMER0_BASE
+ SP804_TIMER_CONTROL_REG
) & SP804_TIMER_CTRL_ENABLE
) {
151 MmioAnd32 (SP804_TIMER0_BASE
+ SP804_TIMER_CONTROL_REG
, 0);
154 // Disable timer 1 if enabled
155 if (MmioRead32(SP804_TIMER1_BASE
+ SP804_TIMER_CONTROL_REG
) & SP804_TIMER_CTRL_ENABLE
) {
156 MmioAnd32 (SP804_TIMER1_BASE
+ SP804_TIMER_CONTROL_REG
, 0);
159 // Disable timer 2 if enabled
160 if (MmioRead32(SP804_TIMER2_BASE
+ SP804_TIMER_CONTROL_REG
) & SP804_TIMER_CTRL_ENABLE
) {
161 MmioAnd32 (SP804_TIMER2_BASE
+ SP804_TIMER_CONTROL_REG
, 0);
164 // Disable timer 3 if enabled
165 if (MmioRead32(SP804_TIMER3_BASE
+ SP804_TIMER_CONTROL_REG
) & SP804_TIMER_CTRL_ENABLE
) {
166 MmioAnd32 (SP804_TIMER3_BASE
+ SP804_TIMER_CONTROL_REG
, 0);
172 This function adjusts the period of timer interrupts to the value specified
173 by TimerPeriod. If the timer period is updated, then the selected timer
174 period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If
175 the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.
176 If an error occurs while attempting to update the timer period, then the
177 timer hardware will be put back in its state prior to this call, and
178 EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt
179 is disabled. This is not the same as disabling the CPU's interrupts.
180 Instead, it must either turn off the timer hardware, or it must adjust the
181 interrupt controller so that a CPU interrupt is not generated when the timer
184 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
185 @param TimerPeriod The rate to program the timer interrupt in 100 nS units. If
186 the timer hardware is not programmable, then EFI_UNSUPPORTED is
187 returned. If the timer is programmable, then the timer period
188 will be rounded up to the nearest timer period that is supported
189 by the timer hardware. If TimerPeriod is set to 0, then the
190 timer interrupts will be disabled.
193 @retval EFI_SUCCESS The timer period was changed.
194 @retval EFI_UNSUPPORTED The platform cannot change the period of the timer interrupt.
195 @retval EFI_DEVICE_ERROR The timer period could not be changed due to a device error.
200 TimerDriverSetTimerPeriod (
201 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
202 IN UINT64 TimerPeriod
208 // always disable the timer
209 MmioAnd32 (SP804_TIMER0_BASE
+ SP804_TIMER_CONTROL_REG
, ~SP804_TIMER_CTRL_ENABLE
);
211 if (TimerPeriod
== 0) {
212 // leave timer disabled from above, and...
214 // disable timer 0/1 interrupt for a TimerPeriod of 0
215 Status
= gInterrupt
->DisableInterruptSource (gInterrupt
, gVector
);
217 // Convert TimerPeriod into 1MHz clock counts (us units = 100ns units / 10)
218 TimerTicks
= DivU64x32 (TimerPeriod
, 10);
220 // if it's larger than 32-bits, pin to highest value
221 if (TimerTicks
> 0xffffffff) {
223 TimerTicks
= 0xffffffff;
227 // Program the SP804 timer with the new count value
228 MmioWrite32 (SP804_TIMER0_BASE
+ SP804_TIMER_LOAD_REG
, TimerTicks
);
231 MmioOr32 (SP804_TIMER0_BASE
+ SP804_TIMER_CONTROL_REG
, SP804_TIMER_CTRL_ENABLE
);
233 // enable timer 0/1 interrupts
234 Status
= gInterrupt
->EnableInterruptSource (gInterrupt
, gVector
);
237 // Save the new timer period
238 mTimerPeriod
= TimerPeriod
;
243 This function retrieves the period of timer interrupts in 100 ns units,
244 returns that value in TimerPeriod, and returns EFI_SUCCESS. If TimerPeriod
245 is NULL, then EFI_INVALID_PARAMETER is returned. If a TimerPeriod of 0 is
246 returned, then the timer is currently disabled.
248 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
249 @param TimerPeriod A pointer to the timer period to retrieve in 100 ns units. If
250 0 is returned, then the timer is currently disabled.
253 @retval EFI_SUCCESS The timer period was returned in TimerPeriod.
254 @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.
259 TimerDriverGetTimerPeriod (
260 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
261 OUT UINT64
*TimerPeriod
264 if (TimerPeriod
== NULL
) {
265 return EFI_INVALID_PARAMETER
;
268 *TimerPeriod
= mTimerPeriod
;
273 This function generates a soft timer interrupt. If the platform does not support soft
274 timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.
275 If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()
276 service, then a soft timer interrupt will be generated. If the timer interrupt is
277 enabled when this service is called, then the registered handler will be invoked. The
278 registered handler should not be able to distinguish a hardware-generated timer
279 interrupt from a software-generated timer interrupt.
281 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
283 @retval EFI_SUCCESS The soft timer interrupt was generated.
284 @retval EFI_UNSUPPORTED The platform does not support the generation of soft timer interrupts.
289 TimerDriverGenerateSoftInterrupt (
290 IN EFI_TIMER_ARCH_PROTOCOL
*This
293 return EFI_UNSUPPORTED
;
297 Interface structure for the Timer Architectural Protocol.
299 @par Protocol Description:
300 This protocol provides the services to initialize a periodic timer
301 interrupt, and to register a handler that is called each time the timer
302 interrupt fires. It may also provide a service to adjust the rate of the
303 periodic timer interrupt. When a timer interrupt occurs, the handler is
304 passed the amount of time that has passed since the previous timer
307 @param RegisterHandler
308 Registers a handler that will be called each time the
309 timer interrupt fires. TimerPeriod defines the minimum
310 time between timer interrupts, so TimerPeriod will also
311 be the minimum time between calls to the registered
314 @param SetTimerPeriod
315 Sets the period of the timer interrupt in 100 nS units.
316 This function is optional, and may return EFI_UNSUPPORTED.
317 If this function is supported, then the timer period will
318 be rounded up to the nearest supported timer period.
321 @param GetTimerPeriod
322 Retrieves the period of the timer interrupt in 100 nS units.
324 @param GenerateSoftInterrupt
325 Generates a soft timer interrupt that simulates the firing of
326 the timer interrupt. This service can be used to invoke the registered handler if the timer interrupt has been masked for
330 EFI_TIMER_ARCH_PROTOCOL gTimer
= {
331 TimerDriverRegisterHandler
,
332 TimerDriverSetTimerPeriod
,
333 TimerDriverGetTimerPeriod
,
334 TimerDriverGenerateSoftInterrupt
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
;
361 // Find the interrupt controller protocol. ASSERT if not found.
362 Status
= gBS
->LocateProtocol (&gHardwareInterruptProtocolGuid
, NULL
, (VOID
**)&gInterrupt
);
363 ASSERT_EFI_ERROR (Status
);
365 // Configure 1MHz clock
366 MmioOr32 (SP810_CTRL_BASE
+ SP810_SYS_CTRL_REG
, SP810_SYS_CTRL_TIMER1_TIMCLK
);
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
= TIMER01_INTERRUPT_NUM
;
383 Status
= gInterrupt
->RegisterInterruptSource (gInterrupt
, gVector
, TimerInterruptHandler
);
384 ASSERT_EFI_ERROR (Status
);
386 // configure periodic timer (TIMER0) for 1MHz operation
387 MmioOr32 (SP810_CTRL_BASE
+ SP810_SYS_CTRL_REG
, SP810_SYS_CTRL_TIMER0_TIMCLK
);
389 // configure timer 0 for periodic operation, 32 bits, no prescaler, and interrupt enabled
390 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
);
392 // Set up default timer
393 Status
= TimerDriverSetTimerPeriod (&gTimer
, FixedPcdGet32(PcdTimerPeriod
)); // TIMER_DEFAULT_PERIOD
394 ASSERT_EFI_ERROR (Status
);
396 // Install the Timer Architectural Protocol onto a new handle
397 Status
= gBS
->InstallMultipleProtocolInterfaces(
399 &gEfiTimerArchProtocolGuid
, &gTimer
,
402 ASSERT_EFI_ERROR(Status
);
404 // Register for an ExitBootServicesEvent
405 Status
= gBS
->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES
, TPL_NOTIFY
, ExitBootServicesEvent
, NULL
, &EfiExitBootServicesEvent
);
406 ASSERT_EFI_ERROR (Status
);