]>
Commit | Line | Data |
---|---|---|
1 | /** @file | |
2 | Timer Architecture Protocol driver of the ARM flavor | |
3 | ||
4 | Copyright (c) 2011 ARM Ltd. All rights reserved.<BR> | |
5 | ||
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 | |
10 | ||
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. | |
13 | ||
14 | **/ | |
15 | ||
16 | ||
17 | #include <PiDxe.h> | |
18 | ||
19 | #include <Library/ArmLib.h> | |
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 | #include <Library/ArmV7ArchTimerLib.h> | |
28 | ||
29 | #include <Protocol/Timer.h> | |
30 | #include <Protocol/HardwareInterrupt.h> | |
31 | ||
32 | // The notification function to call on every timer interrupt. | |
33 | EFI_TIMER_NOTIFY mTimerNotifyFunction = (EFI_TIMER_NOTIFY)NULL; | |
34 | EFI_EVENT EfiExitBootServicesEvent = (EFI_EVENT)NULL; | |
35 | ||
36 | // The current period of the timer interrupt | |
37 | UINT64 mTimerPeriod = 0; | |
38 | ||
39 | // Cached copy of the Hardware Interrupt protocol instance | |
40 | EFI_HARDWARE_INTERRUPT_PROTOCOL *gInterrupt = NULL; | |
41 | ||
42 | /** | |
43 | This function registers the handler NotifyFunction so it is called every time | |
44 | the timer interrupt fires. It also passes the amount of time since the last | |
45 | handler call to the NotifyFunction. If NotifyFunction is NULL, then the | |
46 | handler is unregistered. If the handler is registered, then EFI_SUCCESS is | |
47 | returned. If the CPU does not support registering a timer interrupt handler, | |
48 | then EFI_UNSUPPORTED is returned. If an attempt is made to register a handler | |
49 | when a handler is already registered, then EFI_ALREADY_STARTED is returned. | |
50 | If an attempt is made to unregister a handler when a handler is not registered, | |
51 | then EFI_INVALID_PARAMETER is returned. If an error occurs attempting to | |
52 | register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR | |
53 | is returned. | |
54 | ||
55 | @param This The EFI_TIMER_ARCH_PROTOCOL instance. | |
56 | @param NotifyFunction The function to call when a timer interrupt fires. This | |
57 | function executes at TPL_HIGH_LEVEL. The DXE Core will | |
58 | register a handler for the timer interrupt, so it can know | |
59 | how much time has passed. This information is used to | |
60 | signal timer based events. NULL will unregister the handler. | |
61 | @retval EFI_SUCCESS The timer handler was registered. | |
62 | @retval EFI_UNSUPPORTED The platform does not support timer interrupts. | |
63 | @retval EFI_ALREADY_STARTED NotifyFunction is not NULL, and a handler is already | |
64 | registered. | |
65 | @retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not | |
66 | previously registered. | |
67 | @retval EFI_DEVICE_ERROR The timer handler could not be registered. | |
68 | ||
69 | **/ | |
70 | EFI_STATUS | |
71 | EFIAPI | |
72 | TimerDriverRegisterHandler ( | |
73 | IN EFI_TIMER_ARCH_PROTOCOL *This, | |
74 | IN EFI_TIMER_NOTIFY NotifyFunction | |
75 | ) | |
76 | { | |
77 | if ((NotifyFunction == NULL) && (mTimerNotifyFunction == NULL)) { | |
78 | return EFI_INVALID_PARAMETER; | |
79 | } | |
80 | ||
81 | if ((NotifyFunction != NULL) && (mTimerNotifyFunction != NULL)) { | |
82 | return EFI_ALREADY_STARTED; | |
83 | } | |
84 | ||
85 | mTimerNotifyFunction = NotifyFunction; | |
86 | ||
87 | return EFI_SUCCESS; | |
88 | } | |
89 | ||
90 | /** | |
91 | Disable the timer | |
92 | **/ | |
93 | VOID | |
94 | EFIAPI | |
95 | ExitBootServicesEvent ( | |
96 | IN EFI_EVENT Event, | |
97 | IN VOID *Context | |
98 | ) | |
99 | { | |
100 | ArmArchTimerDisableTimer (); | |
101 | } | |
102 | ||
103 | /** | |
104 | ||
105 | This function adjusts the period of timer interrupts to the value specified | |
106 | by TimerPeriod. If the timer period is updated, then the selected timer | |
107 | period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If | |
108 | the timer hardware is not programmable, then EFI_UNSUPPORTED is returned. | |
109 | If an error occurs while attempting to update the timer period, then the | |
110 | timer hardware will be put back in its state prior to this call, and | |
111 | EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt | |
112 | is disabled. This is not the same as disabling the CPU's interrupts. | |
113 | Instead, it must either turn off the timer hardware, or it must adjust the | |
114 | interrupt controller so that a CPU interrupt is not generated when the timer | |
115 | interrupt fires. | |
116 | ||
117 | @param This The EFI_TIMER_ARCH_PROTOCOL instance. | |
118 | @param TimerPeriod The rate to program the timer interrupt in 100 nS units. If | |
119 | the timer hardware is not programmable, then EFI_UNSUPPORTED is | |
120 | returned. If the timer is programmable, then the timer period | |
121 | will be rounded up to the nearest timer period that is supported | |
122 | by the timer hardware. If TimerPeriod is set to 0, then the | |
123 | timer interrupts will be disabled. | |
124 | ||
125 | ||
126 | @retval EFI_SUCCESS The timer period was changed. | |
127 | @retval EFI_UNSUPPORTED The platform cannot change the period of the timer interrupt. | |
128 | @retval EFI_DEVICE_ERROR The timer period could not be changed due to a device error. | |
129 | ||
130 | **/ | |
131 | EFI_STATUS | |
132 | EFIAPI | |
133 | TimerDriverSetTimerPeriod ( | |
134 | IN EFI_TIMER_ARCH_PROTOCOL *This, | |
135 | IN UINT64 TimerPeriod | |
136 | ) | |
137 | { | |
138 | UINT64 TimerTicks; | |
139 | ||
140 | // always disable the timer | |
141 | ArmArchTimerDisableTimer (); | |
142 | ||
143 | if (TimerPeriod != 0) { | |
144 | // Convert TimerPeriod to micro sec units | |
145 | TimerTicks = DivU64x32 (TimerPeriod, 10); | |
146 | ||
147 | TimerTicks = MultU64x32 (TimerPeriod, (PcdGet32(PcdArmArchTimerFreqInHz)/1000000)); | |
148 | ||
149 | ArmArchTimerSetTimerVal((UINTN)TimerTicks); | |
150 | ||
151 | // Enable the timer | |
152 | ArmArchTimerEnableTimer (); | |
153 | } | |
154 | ||
155 | // Save the new timer period | |
156 | mTimerPeriod = TimerPeriod; | |
157 | return EFI_SUCCESS; | |
158 | } | |
159 | ||
160 | /** | |
161 | This function retrieves the period of timer interrupts in 100 ns units, | |
162 | returns that value in TimerPeriod, and returns EFI_SUCCESS. If TimerPeriod | |
163 | is NULL, then EFI_INVALID_PARAMETER is returned. If a TimerPeriod of 0 is | |
164 | returned, then the timer is currently disabled. | |
165 | ||
166 | @param This The EFI_TIMER_ARCH_PROTOCOL instance. | |
167 | @param TimerPeriod A pointer to the timer period to retrieve in 100 ns units. If | |
168 | 0 is returned, then the timer is currently disabled. | |
169 | ||
170 | ||
171 | @retval EFI_SUCCESS The timer period was returned in TimerPeriod. | |
172 | @retval EFI_INVALID_PARAMETER TimerPeriod is NULL. | |
173 | ||
174 | **/ | |
175 | EFI_STATUS | |
176 | EFIAPI | |
177 | TimerDriverGetTimerPeriod ( | |
178 | IN EFI_TIMER_ARCH_PROTOCOL *This, | |
179 | OUT UINT64 *TimerPeriod | |
180 | ) | |
181 | { | |
182 | if (TimerPeriod == NULL) { | |
183 | return EFI_INVALID_PARAMETER; | |
184 | } | |
185 | ||
186 | *TimerPeriod = mTimerPeriod; | |
187 | return EFI_SUCCESS; | |
188 | } | |
189 | ||
190 | /** | |
191 | This function generates a soft timer interrupt. If the platform does not support soft | |
192 | timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned. | |
193 | If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler() | |
194 | service, then a soft timer interrupt will be generated. If the timer interrupt is | |
195 | enabled when this service is called, then the registered handler will be invoked. The | |
196 | registered handler should not be able to distinguish a hardware-generated timer | |
197 | interrupt from a software-generated timer interrupt. | |
198 | ||
199 | @param This The EFI_TIMER_ARCH_PROTOCOL instance. | |
200 | ||
201 | @retval EFI_SUCCESS The soft timer interrupt was generated. | |
202 | @retval EFI_UNSUPPORTED The platform does not support the generation of soft timer interrupts. | |
203 | ||
204 | **/ | |
205 | EFI_STATUS | |
206 | EFIAPI | |
207 | TimerDriverGenerateSoftInterrupt ( | |
208 | IN EFI_TIMER_ARCH_PROTOCOL *This | |
209 | ) | |
210 | { | |
211 | return EFI_UNSUPPORTED; | |
212 | } | |
213 | ||
214 | /** | |
215 | Interface structure for the Timer Architectural Protocol. | |
216 | ||
217 | @par Protocol Description: | |
218 | This protocol provides the services to initialize a periodic timer | |
219 | interrupt, and to register a handler that is called each time the timer | |
220 | interrupt fires. It may also provide a service to adjust the rate of the | |
221 | periodic timer interrupt. When a timer interrupt occurs, the handler is | |
222 | passed the amount of time that has passed since the previous timer | |
223 | interrupt. | |
224 | ||
225 | @param RegisterHandler | |
226 | Registers a handler that will be called each time the | |
227 | timer interrupt fires. TimerPeriod defines the minimum | |
228 | time between timer interrupts, so TimerPeriod will also | |
229 | be the minimum time between calls to the registered | |
230 | handler. | |
231 | ||
232 | @param SetTimerPeriod | |
233 | Sets the period of the timer interrupt in 100 nS units. | |
234 | This function is optional, and may return EFI_UNSUPPORTED. | |
235 | If this function is supported, then the timer period will | |
236 | be rounded up to the nearest supported timer period. | |
237 | ||
238 | ||
239 | @param GetTimerPeriod | |
240 | Retrieves the period of the timer interrupt in 100 nS units. | |
241 | ||
242 | @param GenerateSoftInterrupt | |
243 | Generates a soft timer interrupt that simulates the firing of | |
244 | the timer interrupt. This service can be used to invoke the registered handler if the timer interrupt has been masked for | |
245 | a period of time. | |
246 | ||
247 | **/ | |
248 | EFI_TIMER_ARCH_PROTOCOL gTimer = { | |
249 | TimerDriverRegisterHandler, | |
250 | TimerDriverSetTimerPeriod, | |
251 | TimerDriverGetTimerPeriod, | |
252 | TimerDriverGenerateSoftInterrupt | |
253 | }; | |
254 | ||
255 | /** | |
256 | ||
257 | C Interrupt Handler called in the interrupt context when Source interrupt is active. | |
258 | ||
259 | ||
260 | @param Source Source of the interrupt. Hardware routing off a specific platform defines | |
261 | what source means. | |
262 | ||
263 | @param SystemContext Pointer to system register context. Mostly used by debuggers and will | |
264 | update the system context after the return from the interrupt if | |
265 | modified. Don't change these values unless you know what you are doing | |
266 | ||
267 | **/ | |
268 | VOID | |
269 | EFIAPI | |
270 | TimerInterruptHandler ( | |
271 | IN HARDWARE_INTERRUPT_SOURCE Source, | |
272 | IN EFI_SYSTEM_CONTEXT SystemContext | |
273 | ) | |
274 | { | |
275 | EFI_TPL OriginalTPL; | |
276 | ||
277 | // | |
278 | // DXE core uses this callback for the EFI timer tick. The DXE core uses locks | |
279 | // that raise to TPL_HIGH and then restore back to current level. Thus we need | |
280 | // to make sure TPL level is set to TPL_HIGH while we are handling the timer tick. | |
281 | // | |
282 | OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL); | |
283 | ||
284 | // Check if the timer interrupt is active | |
285 | if ((ArmArchTimerGetTimerCtrlReg () ) & ARM_ARCH_TIMER_ISTATUS) { | |
286 | ||
287 | // Signal end of interrupt early to help avoid losing subsequent ticks from long duration handlers | |
288 | gInterrupt->EndOfInterrupt (gInterrupt, Source); | |
289 | ||
290 | if (mTimerNotifyFunction) { | |
291 | mTimerNotifyFunction (mTimerPeriod); | |
292 | } | |
293 | ||
294 | // Reload the Timer | |
295 | TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod)); | |
296 | } | |
297 | ||
298 | // Enable timer interrupts | |
299 | gInterrupt->EnableInterruptSource (gInterrupt, Source); | |
300 | ||
301 | gBS->RestoreTPL (OriginalTPL); | |
302 | } | |
303 | ||
304 | ||
305 | /** | |
306 | Initialize the state information for the Timer Architectural Protocol and | |
307 | the Timer Debug support protocol that allows the debugger to break into a | |
308 | running program. | |
309 | ||
310 | @param ImageHandle of the loaded driver | |
311 | @param SystemTable Pointer to the System Table | |
312 | ||
313 | @retval EFI_SUCCESS Protocol registered | |
314 | @retval EFI_OUT_OF_RESOURCES Cannot allocate protocol data structure | |
315 | @retval EFI_DEVICE_ERROR Hardware problems | |
316 | ||
317 | **/ | |
318 | EFI_STATUS | |
319 | EFIAPI | |
320 | TimerInitialize ( | |
321 | IN EFI_HANDLE ImageHandle, | |
322 | IN EFI_SYSTEM_TABLE *SystemTable | |
323 | ) | |
324 | { | |
325 | EFI_HANDLE Handle = NULL; | |
326 | EFI_STATUS Status; | |
327 | UINTN TimerCtrlReg; | |
328 | ||
329 | if (ArmIsArchTimerImplemented () == 0) { | |
330 | DEBUG ((EFI_D_ERROR, "ARM Architectural Timer is not available in the CPU, hence cann't use this Driver \n")); | |
331 | ASSERT (0); | |
332 | } | |
333 | ||
334 | // Find the interrupt controller protocol. ASSERT if not found. | |
335 | Status = gBS->LocateProtocol (&gHardwareInterruptProtocolGuid, NULL, (VOID **)&gInterrupt); | |
336 | ASSERT_EFI_ERROR (Status); | |
337 | ||
338 | // Disable the timer | |
339 | Status = TimerDriverSetTimerPeriod (&gTimer, 0); | |
340 | ASSERT_EFI_ERROR (Status); | |
341 | ||
342 | // Install secure and Non-secure interrupt handlers | |
343 | // Note: Because it is not possible to determine the security state of the | |
344 | // CPU dynamically, we just install interrupt handler for both sec and non-sec | |
345 | // timer PPI | |
346 | Status = gInterrupt->RegisterInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerSecIntrNum), TimerInterruptHandler); | |
347 | ASSERT_EFI_ERROR (Status); | |
348 | ||
349 | Status = gInterrupt->RegisterInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerIntrNum), TimerInterruptHandler); | |
350 | ASSERT_EFI_ERROR (Status); | |
351 | ||
352 | // Unmask timer interrupts | |
353 | TimerCtrlReg = ArmArchTimerGetTimerCtrlReg (); | |
354 | TimerCtrlReg &= ~ARM_ARCH_TIMER_IMASK; | |
355 | ArmArchTimerSetTimerCtrlReg (TimerCtrlReg); | |
356 | ||
357 | // Set up default timer | |
358 | Status = TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod)); // TIMER_DEFAULT_PERIOD | |
359 | ASSERT_EFI_ERROR (Status); | |
360 | ||
361 | // Install the Timer Architectural Protocol onto a new handle | |
362 | Status = gBS->InstallMultipleProtocolInterfaces( | |
363 | &Handle, | |
364 | &gEfiTimerArchProtocolGuid, &gTimer, | |
365 | NULL | |
366 | ); | |
367 | ASSERT_EFI_ERROR(Status); | |
368 | ||
369 | // enable Secure timer interrupts | |
370 | Status = gInterrupt->EnableInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerSecIntrNum)); | |
371 | ||
372 | // enable NonSecure timer interrupts | |
373 | Status = gInterrupt->EnableInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerIntrNum)); | |
374 | ||
375 | // Register for an ExitBootServicesEvent | |
376 | Status = gBS->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_NOTIFY, ExitBootServicesEvent, NULL, &EfiExitBootServicesEvent); | |
377 | ASSERT_EFI_ERROR (Status); | |
378 | ||
379 | return Status; | |
380 | } |