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>
26 #include <Library/OmapLib.h>
28 #include <Protocol/Timer.h>
29 #include <Protocol/HardwareInterrupt.h>
31 #include <ArmEb/ArmEb.h>
34 // The notification function to call on every timer interrupt.
35 volatile EFI_TIMER_NOTIFY mTimerNotifyFunction
= (EFI_TIMER_NOTIFY
)NULL
;
38 // The current period of the timer interrupt
39 volatile UINT64 mTimerPeriod
= 0;
41 // Cached copy of the Hardware Interrupt protocol instance
42 EFI_HARDWARE_INTERRUPT_PROTOCOL
*gInterrupt
= NULL
;
44 // Cached interrupt vector
50 C Interrupt Handler calledin 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
78 MmioWrite32 (EB_SP804_TIMER0_BASE
+ SP804_TIMER_INT_CLR_REG
, 0);
80 // signal end of interrupt early to help avoid losing subsequent ticks from long duration handlers
81 gInterrupt
->EndOfInterrupt (gInterrupt
, Source
);
83 if (mTimerNotifyFunction
) {
84 mTimerNotifyFunction (mTimerPeriod
);
87 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
;
141 This function adjusts the period of timer interrupts to the value specified
142 by TimerPeriod. If the timer period is updated, then the selected timer
143 period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If
144 the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.
145 If an error occurs while attempting to update the timer period, then the
146 timer hardware will be put back in its state prior to this call, and
147 EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt
148 is disabled. This is not the same as disabling the CPU's interrupts.
149 Instead, it must either turn off the timer hardware, or it must adjust the
150 interrupt controller so that a CPU interrupt is not generated when the timer
153 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
154 @param TimerPeriod The rate to program the timer interrupt in 100 nS units. If
155 the timer hardware is not programmable, then EFI_UNSUPPORTED is
156 returned. If the timer is programmable, then the timer period
157 will be rounded up to the nearest timer period that is supported
158 by the timer hardware. If TimerPeriod is set to 0, then the
159 timer interrupts will be disabled.
162 @retval EFI_SUCCESS The timer period was changed.
163 @retval EFI_UNSUPPORTED The platform cannot change the period of the timer interrupt.
164 @retval EFI_DEVICE_ERROR The timer period could not be changed due to a device error.
169 TimerDriverSetTimerPeriod (
170 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
171 IN UINT64 TimerPeriod
177 // always disable the timer
178 MmioAnd32 (EB_SP804_TIMER0_BASE
+ SP804_TIMER_CONTROL_REG
, ~SP804_TIMER_CTRL_ENABLE
);
180 if (TimerPeriod
== 0) {
181 // leave timer disabled from above, and...
182 // disable timer 0/1 interrupt for a TimerPeriod of 0
184 Status
= gInterrupt
->DisableInterruptSource (gInterrupt
, gVector
);
186 // Convert TimerPeriod into 1MHz clock counts (us units = 100ns units / 10)
187 TimerTicks
= DivU64x32 (TimerPeriod
, 10, NULL
);
189 // if it's larger than 32-bits, pin to highest value
190 if (TimerTicks
> 0xffffffff) {
191 TimerTicks
= 0xffffffff;
194 // Program the SP804 timer with the new count value
195 MmioWrite32 (EB_SP804_TIMER0_BASE
+ SP804_TIMER_LOAD_REG
, TimerTicks
);
198 MmioOr32 (EB_SP804_TIMER0_BASE
+ SP804_TIMER_CONTROL_REG
, SP804_TIMER_CTRL_ENABLE
);
200 // enable timer 0/1 interrupts
201 Status
= gInterrupt
->EnableInterruptSource (gInterrupt
, gVector
);
205 // Save the new timer period
207 mTimerPeriod
= TimerPeriod
;
213 This function retrieves the period of timer interrupts in 100 ns units,
214 returns that value in TimerPeriod, and returns EFI_SUCCESS. If TimerPeriod
215 is NULL, then EFI_INVALID_PARAMETER is returned. If a TimerPeriod of 0 is
216 returned, then the timer is currently disabled.
218 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
219 @param TimerPeriod A pointer to the timer period to retrieve in 100 ns units. If
220 0 is returned, then the timer is currently disabled.
223 @retval EFI_SUCCESS The timer period was returned in TimerPeriod.
224 @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.
229 TimerDriverGetTimerPeriod (
230 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
231 OUT UINT64
*TimerPeriod
234 if (TimerPeriod
== NULL
) {
235 return EFI_INVALID_PARAMETER
;
238 *TimerPeriod
= mTimerPeriod
;
243 This function generates a soft timer interrupt. If the platform does not support soft
244 timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.
245 If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()
246 service, then a soft timer interrupt will be generated. If the timer interrupt is
247 enabled when this service is called, then the registered handler will be invoked. The
248 registered handler should not be able to distinguish a hardware-generated timer
249 interrupt from a software-generated timer interrupt.
251 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
253 @retval EFI_SUCCESS The soft timer interrupt was generated.
254 @retval EFI_UNSUPPORTED The platform does not support the generation of soft timer interrupts.
259 TimerDriverGenerateSoftInterrupt (
260 IN EFI_TIMER_ARCH_PROTOCOL
*This
263 return EFI_UNSUPPORTED
;
269 Interface stucture for the Timer Architectural Protocol.
271 @par Protocol Description:
272 This protocol provides the services to initialize a periodic timer
273 interrupt, and to register a handler that is called each time the timer
274 interrupt fires. It may also provide a service to adjust the rate of the
275 periodic timer interrupt. When a timer interrupt occurs, the handler is
276 passed the amount of time that has passed since the previous timer
279 @param RegisterHandler
280 Registers a handler that will be called each time the
281 timer interrupt fires. TimerPeriod defines the minimum
282 time between timer interrupts, so TimerPeriod will also
283 be the minimum time between calls to the registered
286 @param SetTimerPeriod
287 Sets the period of the timer interrupt in 100 nS units.
288 This function is optional, and may return EFI_UNSUPPORTED.
289 If this function is supported, then the timer period will
290 be rounded up to the nearest supported timer period.
293 @param GetTimerPeriod
294 Retrieves the period of the timer interrupt in 100 nS units.
296 @param GenerateSoftInterrupt
297 Generates a soft timer interrupt that simulates the firing of
298 the timer interrupt. This service can be used to invoke the registered handler if the timer interrupt has been masked for
302 EFI_TIMER_ARCH_PROTOCOL gTimer
= {
303 TimerDriverRegisterHandler
,
304 TimerDriverSetTimerPeriod
,
305 TimerDriverGetTimerPeriod
,
306 TimerDriverGenerateSoftInterrupt
311 Initialize the state information for the Timer Architectural Protocol and
312 the Timer Debug support protocol that allows the debugger to break into a
315 @param ImageHandle of the loaded driver
316 @param SystemTable Pointer to the System Table
318 @retval EFI_SUCCESS Protocol registered
319 @retval EFI_OUT_OF_RESOURCES Cannot allocate protocol data structure
320 @retval EFI_DEVICE_ERROR Hardware problems
326 IN EFI_HANDLE ImageHandle
,
327 IN EFI_SYSTEM_TABLE
*SystemTable
330 EFI_HANDLE Handle
= NULL
;
332 UINT32 TimerBaseAddress
;
334 // configure free running timer (TIMER1) for 1MHz operation
336 // AND disable clock, OR configure 1MHz clock
337 MmioAndThenOr32 (EB_SP810_CTRL_BASE
+ SP810_SYS_CTRL_REG
, ~SP810_SYS_CTRL_TIMER1_EN
, SP810_SYS_CTRL_TIMER1_TIMCLK
);
340 MmioOr32 (EB_SP810_CTRL_BASE
+ SP810_SYS_CTRL_REG
, SP810_SYS_CTRL_TIMER1_EN
);
343 // configure timer 1 for free running operation, 32 bits, no prescaler, interrupt disabled
344 MmioWrite32 (EB_SP804_TIMER1_BASE
+ SP804_TIMER_CONTROL_REG
, SP804_TIMER_CTRL_32BIT
| SP804_PRESCALE_DIV_1
);
346 // enable the free running timer
347 MmioOr32 (EB_SP804_TIMER1_BASE
+ SP804_TIMER_CONTROL_REG
, SP804_TIMER_CTRL_ENABLE
);
349 // record free running tick value (should be close to 0xffffffff)
350 mLastTickCount
= MmioRead32 (EB_SP804_TIMER1_BASE
+ SP804_TIMER_CURRENT_REG
);
353 Status
= TimerDriverSetTimerPeriod (&gTimer
, 0);
354 ASSERT_EFI_ERROR (Status
);
356 // Install interrupt handler for SP804 timer 0/1 interrupts
357 Status
= mGic
->RegisterInterruptHandler(mGic
, EB_TIMER01_INTERRUPT_NUM
, TimerInterruptHandler
);
358 ASSERT_EFI_ERROR (Status
);
360 // Install interrupt handler
361 gVector
= EB_TIMER01_INTERRUPT_NUM
;
362 Status
= gInterrupt
->RegisterInterruptSource (gInterrupt
, gVector
, TimerInterruptHandler
);
363 ASSERT_EFI_ERROR (Status
);
366 // configure periodic timer (TIMER0) for 1MHz operation
367 MmioAndThenOr32 (EB_SP810_CTRL_BASE
+ SP810_SYS_CTRL_REG
, ~SP810_SYS_CTRL_TIMER0_EN
, SP810_SYS_CTRL_TIMER0_TIMCLK
);
370 MmioOr32 (EB_SP810_CTRL_BASE
+ SP810_SYS_CTRL_REG
, SP810_SYS_CTRL_TIMER0_EN
);
372 // configure timer 0 for periodic operation, 32 bits, no prescaler, and interrupt enabled
373 MmioWrite32 (EB_SP804_TIMER0_BASE
+ SP804_TIMER_CONTROL_REG
, SP804_TIMER_CTRL_PERIODIC
| SP804_TIMER_CTRL_32BIT
| SP804_PRESCALE_DIV_1
| SP804_TIMER_CTRL_INT_ENABLE
);
376 // Set up default timer
377 Status
= TimerDriverSetTimerPeriod (&gTimer
, FixedPcdGet32(PcdTimerPeriod
)); // TIMER_DEFAULT_PERIOD
378 ASSERT_EFI_ERROR (Status
);
380 // Install the Timer Architectural Protocol onto a new handle
381 Status
= gBS
->InstallMultipleProtocolInterfaces(
383 &gEfiTimerArchProtocolGuid
, &gTimer
,
386 ASSERT_EFI_ERROR(Status
);