ArmPlatformPkg: Minor code changes (comments, misspellings, coding stylei, line endings)
[mirror_edk2.git] / ArmPlatformPkg / Drivers / SP804TimerDxe / SP804Timer.c
1 /** @file
2 Template for Timer Architecture Protocol driver of the ARM flavor
3
4 Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
5 Copyright (c) 2011 - 2012, ARM Ltd. All rights reserved.<BR>
6
7 This program and the accompanying materials
8 are licensed and made available under the terms and conditions of the BSD License
9 which accompanies this distribution. The full text of the license may be found at
10 http://opensource.org/licenses/bsd-license.php
11
12 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
13 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
14
15 **/
16
17
18 #include <PiDxe.h>
19
20 #include <Library/BaseLib.h>
21 #include <Library/DebugLib.h>
22 #include <Library/BaseMemoryLib.h>
23 #include <Library/UefiBootServicesTableLib.h>
24 #include <Library/UefiLib.h>
25 #include <Library/PcdLib.h>
26 #include <Library/IoLib.h>
27
28 #include <Protocol/Timer.h>
29 #include <Protocol/HardwareInterrupt.h>
30
31 #include <Drivers/SP804Timer.h>
32
33 #define SP804_TIMER_PERIODIC_BASE ((UINTN)PcdGet32 (PcdSP804TimerPeriodicBase))
34 #define SP804_TIMER_METRONOME_BASE ((UINTN)PcdGet32 (PcdSP804TimerMetronomeBase))
35 #define SP804_TIMER_PERFORMANCE_BASE ((UINTN)PcdGet32 (PcdSP804TimerPerformanceBase))
36
37 // The notification function to call on every timer interrupt.
38 EFI_TIMER_NOTIFY mTimerNotifyFunction = (EFI_TIMER_NOTIFY)NULL;
39 EFI_EVENT EfiExitBootServicesEvent = (EFI_EVENT)NULL;
40
41 // The current period of the timer interrupt
42 UINT64 mTimerPeriod = 0;
43
44 // Cached copy of the Hardware Interrupt protocol instance
45 EFI_HARDWARE_INTERRUPT_PROTOCOL *gInterrupt = NULL;
46
47 // Cached interrupt vector
48 UINTN gVector;
49
50
51 /**
52
53 C Interrupt Handler called in the interrupt context when Source interrupt is active.
54
55
56 @param Source Source of the interrupt. Hardware routing off a specific platform defines
57 what source means.
58
59 @param SystemContext Pointer to system register context. Mostly used by debuggers and will
60 update the system context after the return from the interrupt if
61 modified. Don't change these values unless you know what you are doing
62
63 **/
64 VOID
65 EFIAPI
66 TimerInterruptHandler (
67 IN HARDWARE_INTERRUPT_SOURCE Source,
68 IN EFI_SYSTEM_CONTEXT SystemContext
69 )
70 {
71 EFI_TPL OriginalTPL;
72
73 //
74 // DXE core uses this callback for the EFI timer tick. The DXE core uses locks
75 // that raise to TPL_HIGH and then restore back to current level. Thus we need
76 // to make sure TPL level is set to TPL_HIGH while we are handling the timer tick.
77 //
78 OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);
79
80 // If the interrupt is shared then we must check if this interrupt source is the one associated to this Timer
81 if (MmioRead32 (SP804_TIMER_PERIODIC_BASE + SP804_TIMER_MSK_INT_STS_REG) != 0) {
82 // Clear the periodic interrupt
83 MmioWrite32 (SP804_TIMER_PERIODIC_BASE + SP804_TIMER_INT_CLR_REG, 0);
84
85 // Signal end of interrupt early to help avoid losing subsequent ticks from long duration handlers
86 gInterrupt->EndOfInterrupt (gInterrupt, Source);
87
88 if (mTimerNotifyFunction) {
89 mTimerNotifyFunction (mTimerPeriod);
90 }
91 }
92
93 gBS->RestoreTPL (OriginalTPL);
94 }
95
96 /**
97 This function registers the handler NotifyFunction so it is called every time
98 the timer interrupt fires. It also passes the amount of time since the last
99 handler call to the NotifyFunction. If NotifyFunction is NULL, then the
100 handler is unregistered. If the handler is registered, then EFI_SUCCESS is
101 returned. If the CPU does not support registering a timer interrupt handler,
102 then EFI_UNSUPPORTED is returned. If an attempt is made to register a handler
103 when a handler is already registered, then EFI_ALREADY_STARTED is returned.
104 If an attempt is made to unregister a handler when a handler is not registered,
105 then EFI_INVALID_PARAMETER is returned. If an error occurs attempting to
106 register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR
107 is returned.
108
109 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
110 @param NotifyFunction The function to call when a timer interrupt fires. This
111 function executes at TPL_HIGH_LEVEL. The DXE Core will
112 register a handler for the timer interrupt, so it can know
113 how much time has passed. This information is used to
114 signal timer based events. NULL will unregister the handler.
115 @retval EFI_SUCCESS The timer handler was registered.
116 @retval EFI_UNSUPPORTED The platform does not support timer interrupts.
117 @retval EFI_ALREADY_STARTED NotifyFunction is not NULL, and a handler is already
118 registered.
119 @retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not
120 previously registered.
121 @retval EFI_DEVICE_ERROR The timer handler could not be registered.
122
123 **/
124 EFI_STATUS
125 EFIAPI
126 TimerDriverRegisterHandler (
127 IN EFI_TIMER_ARCH_PROTOCOL *This,
128 IN EFI_TIMER_NOTIFY NotifyFunction
129 )
130 {
131 if ((NotifyFunction == NULL) && (mTimerNotifyFunction == NULL)) {
132 return EFI_INVALID_PARAMETER;
133 }
134
135 if ((NotifyFunction != NULL) && (mTimerNotifyFunction != NULL)) {
136 return EFI_ALREADY_STARTED;
137 }
138
139 mTimerNotifyFunction = NotifyFunction;
140
141 return EFI_SUCCESS;
142 }
143
144 /**
145 Make sure all Dual Timers are disabled
146 **/
147 VOID
148 EFIAPI
149 ExitBootServicesEvent (
150 IN EFI_EVENT Event,
151 IN VOID *Context
152 )
153 {
154 // Disable 'Periodic Operation' timer if enabled
155 if (MmioRead32(SP804_TIMER_PERIODIC_BASE + SP804_TIMER_CONTROL_REG) & SP804_TIMER_CTRL_ENABLE) {
156 MmioAnd32 (SP804_TIMER_PERIODIC_BASE + SP804_TIMER_CONTROL_REG, 0);
157 }
158
159 // Disable 'Metronome/Delay' timer if enabled
160 if (MmioRead32(SP804_TIMER_METRONOME_BASE + SP804_TIMER_CONTROL_REG) & SP804_TIMER_CTRL_ENABLE) {
161 MmioAnd32 (SP804_TIMER_METRONOME_BASE + SP804_TIMER_CONTROL_REG, 0);
162 }
163
164 // Disable 'Performance' timer if enabled
165 if (MmioRead32(SP804_TIMER_PERFORMANCE_BASE + SP804_TIMER_CONTROL_REG) & SP804_TIMER_CTRL_ENABLE) {
166 MmioAnd32 (SP804_TIMER_PERFORMANCE_BASE + SP804_TIMER_CONTROL_REG, 0);
167 }
168 }
169
170 /**
171
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
182 interrupt fires.
183
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.
191
192
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.
196
197 **/
198 EFI_STATUS
199 EFIAPI
200 TimerDriverSetTimerPeriod (
201 IN EFI_TIMER_ARCH_PROTOCOL *This,
202 IN UINT64 TimerPeriod
203 )
204 {
205 EFI_STATUS Status;
206 UINT64 TimerTicks;
207
208 // always disable the timer
209 MmioAnd32 (SP804_TIMER_PERIODIC_BASE + SP804_TIMER_CONTROL_REG, ~SP804_TIMER_CTRL_ENABLE);
210
211 if (TimerPeriod == 0) {
212 // Leave timer disabled from above, and...
213
214 // Disable timer 0/1 interrupt for a TimerPeriod of 0
215 Status = gInterrupt->DisableInterruptSource (gInterrupt, gVector);
216 } else {
217 // Convert TimerPeriod into 1MHz clock counts (us units = 100ns units * 10)
218 TimerTicks = DivU64x32 (TimerPeriod, 10);
219 TimerTicks = MultU64x32 (TimerTicks, PcdGet32(PcdSP804TimerFrequencyInMHz));
220
221 // if it's larger than 32-bits, pin to highest value
222 if (TimerTicks > 0xffffffff) {
223 TimerTicks = 0xffffffff;
224 }
225
226 // Program the SP804 timer with the new count value
227 MmioWrite32 (SP804_TIMER_PERIODIC_BASE + SP804_TIMER_LOAD_REG, TimerTicks);
228
229 // enable the timer
230 MmioOr32 (SP804_TIMER_PERIODIC_BASE + SP804_TIMER_CONTROL_REG, SP804_TIMER_CTRL_ENABLE);
231
232 // enable timer 0/1 interrupts
233 Status = gInterrupt->EnableInterruptSource (gInterrupt, gVector);
234 }
235
236 // Save the new timer period
237 mTimerPeriod = TimerPeriod;
238 return Status;
239 }
240
241 /**
242 This function retrieves the period of timer interrupts in 100 ns units,
243 returns that value in TimerPeriod, and returns EFI_SUCCESS. If TimerPeriod
244 is NULL, then EFI_INVALID_PARAMETER is returned. If a TimerPeriod of 0 is
245 returned, then the timer is currently disabled.
246
247 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
248 @param TimerPeriod A pointer to the timer period to retrieve in 100 ns units. If
249 0 is returned, then the timer is currently disabled.
250
251
252 @retval EFI_SUCCESS The timer period was returned in TimerPeriod.
253 @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.
254
255 **/
256 EFI_STATUS
257 EFIAPI
258 TimerDriverGetTimerPeriod (
259 IN EFI_TIMER_ARCH_PROTOCOL *This,
260 OUT UINT64 *TimerPeriod
261 )
262 {
263 if (TimerPeriod == NULL) {
264 return EFI_INVALID_PARAMETER;
265 }
266
267 *TimerPeriod = mTimerPeriod;
268 return EFI_SUCCESS;
269 }
270
271 /**
272 This function generates a soft timer interrupt. If the platform does not support soft
273 timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.
274 If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()
275 service, then a soft timer interrupt will be generated. If the timer interrupt is
276 enabled when this service is called, then the registered handler will be invoked. The
277 registered handler should not be able to distinguish a hardware-generated timer
278 interrupt from a software-generated timer interrupt.
279
280 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
281
282 @retval EFI_SUCCESS The soft timer interrupt was generated.
283 @retval EFI_UNSUPPORTED The platform does not support the generation of soft timer interrupts.
284
285 **/
286 EFI_STATUS
287 EFIAPI
288 TimerDriverGenerateSoftInterrupt (
289 IN EFI_TIMER_ARCH_PROTOCOL *This
290 )
291 {
292 return EFI_UNSUPPORTED;
293 }
294
295 /**
296 Interface structure for the Timer Architectural Protocol.
297
298 @par Protocol Description:
299 This protocol provides the services to initialize a periodic timer
300 interrupt, and to register a handler that is called each time the timer
301 interrupt fires. It may also provide a service to adjust the rate of the
302 periodic timer interrupt. When a timer interrupt occurs, the handler is
303 passed the amount of time that has passed since the previous timer
304 interrupt.
305
306 @param RegisterHandler
307 Registers a handler that will be called each time the
308 timer interrupt fires. TimerPeriod defines the minimum
309 time between timer interrupts, so TimerPeriod will also
310 be the minimum time between calls to the registered
311 handler.
312
313 @param SetTimerPeriod
314 Sets the period of the timer interrupt in 100 nS units.
315 This function is optional, and may return EFI_UNSUPPORTED.
316 If this function is supported, then the timer period will
317 be rounded up to the nearest supported timer period.
318
319
320 @param GetTimerPeriod
321 Retrieves the period of the timer interrupt in 100 nS units.
322
323 @param GenerateSoftInterrupt
324 Generates a soft timer interrupt that simulates the firing of
325 the timer interrupt. This service can be used to invoke the registered handler if the timer interrupt has been masked for
326 a period of time.
327
328 **/
329 EFI_TIMER_ARCH_PROTOCOL gTimer = {
330 TimerDriverRegisterHandler,
331 TimerDriverSetTimerPeriod,
332 TimerDriverGetTimerPeriod,
333 TimerDriverGenerateSoftInterrupt
334 };
335
336
337 /**
338 Initialize the state information for the Timer Architectural Protocol and
339 the Timer Debug support protocol that allows the debugger to break into a
340 running program.
341
342 @param ImageHandle of the loaded driver
343 @param SystemTable Pointer to the System Table
344
345 @retval EFI_SUCCESS Protocol registered
346 @retval EFI_OUT_OF_RESOURCES Cannot allocate protocol data structure
347 @retval EFI_DEVICE_ERROR Hardware problems
348
349 **/
350 EFI_STATUS
351 EFIAPI
352 TimerInitialize (
353 IN EFI_HANDLE ImageHandle,
354 IN EFI_SYSTEM_TABLE *SystemTable
355 )
356 {
357 EFI_HANDLE Handle = NULL;
358 EFI_STATUS Status;
359
360 // Set the interrupt timer number
361 gVector = PcdGet32(PcdSP804TimerPeriodicInterruptNum);
362
363 // Find the interrupt controller protocol. ASSERT if not found.
364 Status = gBS->LocateProtocol (&gHardwareInterruptProtocolGuid, NULL, (VOID **)&gInterrupt);
365 ASSERT_EFI_ERROR (Status);
366
367 // Disable the timer
368 Status = TimerDriverSetTimerPeriod (&gTimer, 0);
369 ASSERT_EFI_ERROR (Status);
370
371 // Install interrupt handler
372 Status = gInterrupt->RegisterInterruptSource (gInterrupt, gVector, TimerInterruptHandler);
373 ASSERT_EFI_ERROR (Status);
374
375 // configure timer 0 for periodic operation, 32 bits, no prescaler, and interrupt enabled
376 MmioWrite32 (SP804_TIMER_PERIODIC_BASE + SP804_TIMER_CONTROL_REG, SP804_TIMER_CTRL_PERIODIC | SP804_TIMER_CTRL_32BIT | SP804_PRESCALE_DIV_1 | SP804_TIMER_CTRL_INT_ENABLE);
377
378 // Set up default timer
379 Status = TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod)); // TIMER_DEFAULT_PERIOD
380 ASSERT_EFI_ERROR (Status);
381
382 // Install the Timer Architectural Protocol onto a new handle
383 Status = gBS->InstallMultipleProtocolInterfaces(
384 &Handle,
385 &gEfiTimerArchProtocolGuid, &gTimer,
386 NULL
387 );
388 ASSERT_EFI_ERROR(Status);
389
390 // Register for an ExitBootServicesEvent
391 Status = gBS->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_NOTIFY, ExitBootServicesEvent, NULL, &EfiExitBootServicesEvent);
392 ASSERT_EFI_ERROR (Status);
393
394 return Status;
395 }