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
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/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>
27
28 #include <Protocol/Timer.h>
29 #include <Protocol/HardwareInterrupt.h>
30
31 #include <Omap3530/Omap3530.h>
32
33
34 // The notification function to call on every timer interrupt.
35 volatile EFI_TIMER_NOTIFY mTimerNotifyFunction = (EFI_TIMER_NOTIFY)NULL;
36
37
38 // The current period of the timer interrupt
39 volatile UINT64 mTimerPeriod = 0;
40
41 // Cached copy of the Hardware Interrupt protocol instance
42 EFI_HARDWARE_INTERRUPT_PROTOCOL *gInterrupt = NULL;
43
44 // Cached registers
45 volatile UINT32 TISR;
46 volatile UINT32 TCLR;
47 volatile UINT32 TLDR;
48 volatile UINT32 TCRR;
49 volatile UINT32 TIER;
50
51 // Cached interrupt vector
52 volatile UINTN gVector;
53
54
55 /**
56
57 C Interrupt Handler calledin the interrupt context when Source interrupt is active.
58
59
60 @param Source Source of the interrupt. Hardware routing off a specific platform defines
61 what source means.
62
63 @param SystemContext Pointer to system register context. Mostly used by debuggers and will
64 update the system context after the return from the interrupt if
65 modified. Don't change these values unless you know what you are doing
66
67 **/
68 VOID
69 EFIAPI
TimerInterruptHandler(IN HARDWARE_INTERRUPT_SOURCE Source,IN EFI_SYSTEM_CONTEXT SystemContext)70 TimerInterruptHandler (
71 IN HARDWARE_INTERRUPT_SOURCE Source,
72 IN EFI_SYSTEM_CONTEXT SystemContext
73 )
74 {
75 EFI_TPL OriginalTPL;
76
77
78
79 //
80 // DXE core uses this callback for the EFI timer tick. The DXE core uses locks
81 // that raise to TPL_HIGH and then restore back to current level. Thus we need
82 // to make sure TPL level is set to TPL_HIGH while we are handling the timer tick.
83 //
84 OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);
85
86 if (mTimerNotifyFunction) {
87 mTimerNotifyFunction(mTimerPeriod);
88 }
89
90 // Clear all timer interrupts
91 MmioWrite32 (TISR, TISR_CLEAR_ALL);
92
93 // Poll interrupt status bits to ensure clearing
94 while ((MmioRead32 (TISR) & TISR_ALL_INTERRUPT_MASK) != TISR_NO_INTERRUPTS_PENDING);
95
96 gBS->RestoreTPL (OriginalTPL);
97 }
98
99 /**
100 This function registers the handler NotifyFunction so it is called every time
101 the timer interrupt fires. It also passes the amount of time since the last
102 handler call to the NotifyFunction. If NotifyFunction is NULL, then the
103 handler is unregistered. If the handler is registered, then EFI_SUCCESS is
104 returned. If the CPU does not support registering a timer interrupt handler,
105 then EFI_UNSUPPORTED is returned. If an attempt is made to register a handler
106 when a handler is already registered, then EFI_ALREADY_STARTED is returned.
107 If an attempt is made to unregister a handler when a handler is not registered,
108 then EFI_INVALID_PARAMETER is returned. If an error occurs attempting to
109 register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR
110 is returned.
111
112 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
113 @param NotifyFunction The function to call when a timer interrupt fires. This
114 function executes at TPL_HIGH_LEVEL. The DXE Core will
115 register a handler for the timer interrupt, so it can know
116 how much time has passed. This information is used to
117 signal timer based events. NULL will unregister the handler.
118 @retval EFI_SUCCESS The timer handler was registered.
119 @retval EFI_UNSUPPORTED The platform does not support timer interrupts.
120 @retval EFI_ALREADY_STARTED NotifyFunction is not NULL, and a handler is already
121 registered.
122 @retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not
123 previously registered.
124 @retval EFI_DEVICE_ERROR The timer handler could not be registered.
125
126 **/
127 EFI_STATUS
128 EFIAPI
TimerDriverRegisterHandler(IN EFI_TIMER_ARCH_PROTOCOL * This,IN EFI_TIMER_NOTIFY NotifyFunction)129 TimerDriverRegisterHandler (
130 IN EFI_TIMER_ARCH_PROTOCOL *This,
131 IN EFI_TIMER_NOTIFY NotifyFunction
132 )
133 {
134 if ((NotifyFunction == NULL) && (mTimerNotifyFunction == NULL)) {
135 return EFI_INVALID_PARAMETER;
136 }
137
138 if ((NotifyFunction != NULL) && (mTimerNotifyFunction != NULL)) {
139 return EFI_ALREADY_STARTED;
140 }
141
142 mTimerNotifyFunction = NotifyFunction;
143
144 return EFI_SUCCESS;
145 }
146
147 /**
148
149 This function adjusts the period of timer interrupts to the value specified
150 by TimerPeriod. If the timer period is updated, then the selected timer
151 period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If
152 the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.
153 If an error occurs while attempting to update the timer period, then the
154 timer hardware will be put back in its state prior to this call, and
155 EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt
156 is disabled. This is not the same as disabling the CPU's interrupts.
157 Instead, it must either turn off the timer hardware, or it must adjust the
158 interrupt controller so that a CPU interrupt is not generated when the timer
159 interrupt fires.
160
161 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
162 @param TimerPeriod The rate to program the timer interrupt in 100 nS units. If
163 the timer hardware is not programmable, then EFI_UNSUPPORTED is
164 returned. If the timer is programmable, then the timer period
165 will be rounded up to the nearest timer period that is supported
166 by the timer hardware. If TimerPeriod is set to 0, then the
167 timer interrupts will be disabled.
168
169
170 @retval EFI_SUCCESS The timer period was changed.
171 @retval EFI_UNSUPPORTED The platform cannot change the period of the timer interrupt.
172 @retval EFI_DEVICE_ERROR The timer period could not be changed due to a device error.
173
174 **/
175 EFI_STATUS
176 EFIAPI
TimerDriverSetTimerPeriod(IN EFI_TIMER_ARCH_PROTOCOL * This,IN UINT64 TimerPeriod)177 TimerDriverSetTimerPeriod (
178 IN EFI_TIMER_ARCH_PROTOCOL *This,
179 IN UINT64 TimerPeriod
180 )
181 {
182 EFI_STATUS Status;
183 UINT64 TimerCount;
184 INT32 LoadValue;
185
186 if (TimerPeriod == 0) {
187 // Turn off GPTIMER3
188 MmioWrite32 (TCLR, TCLR_ST_OFF);
189
190 Status = gInterrupt->DisableInterruptSource(gInterrupt, gVector);
191 } else {
192 // Calculate required timer count
193 TimerCount = DivU64x32(TimerPeriod * 100, PcdGet32(PcdEmbeddedPerformanceCounterPeriodInNanoseconds));
194
195 // Set GPTIMER3 Load register
196 LoadValue = (INT32) -TimerCount;
197 MmioWrite32 (TLDR, LoadValue);
198 MmioWrite32 (TCRR, LoadValue);
199
200 // Enable Overflow interrupt
201 MmioWrite32 (TIER, TIER_TCAR_IT_DISABLE | TIER_OVF_IT_ENABLE | TIER_MAT_IT_DISABLE);
202
203 // Turn on GPTIMER3, it will reload at overflow
204 MmioWrite32 (TCLR, TCLR_AR_AUTORELOAD | TCLR_ST_ON);
205
206 Status = gInterrupt->EnableInterruptSource(gInterrupt, gVector);
207 }
208
209 //
210 // Save the new timer period
211 //
212 mTimerPeriod = TimerPeriod;
213 return Status;
214 }
215
216
217 /**
218 This function retrieves the period of timer interrupts in 100 ns units,
219 returns that value in TimerPeriod, and returns EFI_SUCCESS. If TimerPeriod
220 is NULL, then EFI_INVALID_PARAMETER is returned. If a TimerPeriod of 0 is
221 returned, then the timer is currently disabled.
222
223 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
224 @param TimerPeriod A pointer to the timer period to retrieve in 100 ns units. If
225 0 is returned, then the timer is currently disabled.
226
227
228 @retval EFI_SUCCESS The timer period was returned in TimerPeriod.
229 @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.
230
231 **/
232 EFI_STATUS
233 EFIAPI
TimerDriverGetTimerPeriod(IN EFI_TIMER_ARCH_PROTOCOL * This,OUT UINT64 * TimerPeriod)234 TimerDriverGetTimerPeriod (
235 IN EFI_TIMER_ARCH_PROTOCOL *This,
236 OUT UINT64 *TimerPeriod
237 )
238 {
239 if (TimerPeriod == NULL) {
240 return EFI_INVALID_PARAMETER;
241 }
242
243 *TimerPeriod = mTimerPeriod;
244 return EFI_SUCCESS;
245 }
246
247 /**
248 This function generates a soft timer interrupt. If the platform does not support soft
249 timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.
250 If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()
251 service, then a soft timer interrupt will be generated. If the timer interrupt is
252 enabled when this service is called, then the registered handler will be invoked. The
253 registered handler should not be able to distinguish a hardware-generated timer
254 interrupt from a software-generated timer interrupt.
255
256 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
257
258 @retval EFI_SUCCESS The soft timer interrupt was generated.
259 @retval EFI_UNSUPPORTED The platform does not support the generation of soft timer interrupts.
260
261 **/
262 EFI_STATUS
263 EFIAPI
TimerDriverGenerateSoftInterrupt(IN EFI_TIMER_ARCH_PROTOCOL * This)264 TimerDriverGenerateSoftInterrupt (
265 IN EFI_TIMER_ARCH_PROTOCOL *This
266 )
267 {
268 return EFI_UNSUPPORTED;
269 }
270
271
272 /**
273 Interface stucture for the Timer Architectural Protocol.
274
275 @par Protocol Description:
276 This protocol provides the services to initialize a periodic timer
277 interrupt, and to register a handler that is called each time the timer
278 interrupt fires. It may also provide a service to adjust the rate of the
279 periodic timer interrupt. When a timer interrupt occurs, the handler is
280 passed the amount of time that has passed since the previous timer
281 interrupt.
282
283 @param RegisterHandler
284 Registers a handler that will be called each time the
285 timer interrupt fires. TimerPeriod defines the minimum
286 time between timer interrupts, so TimerPeriod will also
287 be the minimum time between calls to the registered
288 handler.
289
290 @param SetTimerPeriod
291 Sets the period of the timer interrupt in 100 nS units.
292 This function is optional, and may return EFI_UNSUPPORTED.
293 If this function is supported, then the timer period will
294 be rounded up to the nearest supported timer period.
295
296
297 @param GetTimerPeriod
298 Retrieves the period of the timer interrupt in 100 nS units.
299
300 @param GenerateSoftInterrupt
301 Generates a soft timer interrupt that simulates the firing of
302 the timer interrupt. This service can be used to invoke the registered handler if the timer interrupt has been masked for
303 a period of time.
304
305 **/
306 EFI_TIMER_ARCH_PROTOCOL gTimer = {
307 TimerDriverRegisterHandler,
308 TimerDriverSetTimerPeriod,
309 TimerDriverGetTimerPeriod,
310 TimerDriverGenerateSoftInterrupt
311 };
312
313
314 /**
315 Initialize the state information for the Timer Architectural Protocol and
316 the Timer Debug support protocol that allows the debugger to break into a
317 running program.
318
319 @param ImageHandle of the loaded driver
320 @param SystemTable Pointer to the System Table
321
322 @retval EFI_SUCCESS Protocol registered
323 @retval EFI_OUT_OF_RESOURCES Cannot allocate protocol data structure
324 @retval EFI_DEVICE_ERROR Hardware problems
325
326 **/
327 EFI_STATUS
328 EFIAPI
TimerInitialize(IN EFI_HANDLE ImageHandle,IN EFI_SYSTEM_TABLE * SystemTable)329 TimerInitialize (
330 IN EFI_HANDLE ImageHandle,
331 IN EFI_SYSTEM_TABLE *SystemTable
332 )
333 {
334 EFI_HANDLE Handle = NULL;
335 EFI_STATUS Status;
336 UINT32 TimerBaseAddress;
337
338 // Find the interrupt controller protocol. ASSERT if not found.
339 Status = gBS->LocateProtocol (&gHardwareInterruptProtocolGuid, NULL, (VOID **)&gInterrupt);
340 ASSERT_EFI_ERROR (Status);
341
342 // Set up the timer registers
343 TimerBaseAddress = TimerBase (FixedPcdGet32(PcdOmap35xxArchTimer));
344 TISR = TimerBaseAddress + GPTIMER_TISR;
345 TCLR = TimerBaseAddress + GPTIMER_TCLR;
346 TLDR = TimerBaseAddress + GPTIMER_TLDR;
347 TCRR = TimerBaseAddress + GPTIMER_TCRR;
348 TIER = TimerBaseAddress + GPTIMER_TIER;
349
350 // Disable the timer
351 Status = TimerDriverSetTimerPeriod (&gTimer, 0);
352 ASSERT_EFI_ERROR (Status);
353
354 // Install interrupt handler
355 gVector = InterruptVectorForTimer (FixedPcdGet32(PcdOmap35xxArchTimer));
356 Status = gInterrupt->RegisterInterruptSource (gInterrupt, gVector, TimerInterruptHandler);
357 ASSERT_EFI_ERROR (Status);
358
359 // Turn on the functional clock for Timer
360 MmioOr32 (CM_FCLKEN_PER, CM_FCLKEN_PER_EN_GPT3_ENABLE);
361
362 // Set up default timer
363 Status = TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod));
364 ASSERT_EFI_ERROR (Status);
365
366 // Install the Timer Architectural Protocol onto a new handle
367 Status = gBS->InstallMultipleProtocolInterfaces (
368 &Handle,
369 &gEfiTimerArchProtocolGuid, &gTimer,
370 NULL
371 );
372 ASSERT_EFI_ERROR(Status);
373
374 return Status;
375 }
376
377