aboutsummaryrefslogtreecommitdiffstats
path: root/os/hal/ports/KINETIS/LLD/hal_gpt_lld.c
blob: 6e88f88a68f23faefe6a2100ebef47e519817b09 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
/*
    ChibiOS - Copyright (C) 2014 Derek Mulcahy

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

        http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
*/

/**
 * @file    KINETIS/gpt_lld.c
 * @brief   KINETIS GPT subsystem low level driver source.
 *
 * @addtogroup GPT
 * @{
 */

#include "hal.h"

#if HAL_USE_GPT || defined(__DOXYGEN__)

/*===========================================================================*/
/* Driver local definitions.                                                 */
/*===========================================================================*/

/*===========================================================================*/
/* Driver exported variables.                                                */
/*===========================================================================*/

/**
 * @brief   GPTD1 driver identifier.
 * @note    The driver GPTD1 allocates the complex timer PIT0 when enabled.
 */
#if KINETIS_GPT_USE_PIT0 || defined(__DOXYGEN__)
GPTDriver GPTD1;
#endif

/**
 * @brief   GPTD2 driver identifier.
 * @note    The driver GPTD2 allocates the timer PIT1 when enabled.
 */
#if KINETIS_GPT_USE_PIT1 || defined(__DOXYGEN__)
GPTDriver GPTD2;
#endif

/**
 * @brief   GPTD3 driver identifier.
 * @note    The driver GPTD3 allocates the timer PIT2 when enabled.
 */
#if KINETIS_GPT_USE_PIT2 || defined(__DOXYGEN__)
GPTDriver GPTD3;
#endif

/**
 * @brief   GPTD4 driver identifier.
 * @note    The driver GPTD4 allocates the timer PIT3 when enabled.
 */
#if KINETIS_GPT_USE_PIT3 || defined(__DOXYGEN__)
GPTDriver GPTD4;
#endif

/*===========================================================================*/
/* Driver local variables and types.                                         */
/*===========================================================================*/

#if KINETIS_HAS_PIT_COMMON_IRQ
static uint8_t active_channels = 0;
#endif /* KINETIS_HAS_PIT_COMMON_IRQ */

/*===========================================================================*/
/* Driver local functions.                                                   */
/*===========================================================================*/

/**
 * @brief   Shared IRQ handler.
 *
 * @param[in] gptp      pointer to a @p GPTDriver object
 */
static void gpt_lld_serve_interrupt(GPTDriver *gptp) {

  /* Clear the interrupt */
  gptp->channel->TFLG |= PIT_TFLGn_TIF;

  if (gptp->state == GPT_ONESHOT) {
    gptp->state = GPT_READY;                /* Back in GPT_READY state.     */
    gpt_lld_stop_timer(gptp);               /* Timer automatically stopped. */
  }
  gptp->config->callback(gptp);
}

/*===========================================================================*/
/* Driver interrupt handlers.                                                */
/*===========================================================================*/

#if !KINETIS_HAS_PIT_COMMON_IRQ

#if KINETIS_GPT_USE_PIT0
/**
 * @brief   PIT1 interrupt handler.
 *
 * @isr
 */
OSAL_IRQ_HANDLER(KINETIS_PIT0_IRQ_VECTOR) {
  OSAL_IRQ_PROLOGUE();
  gpt_lld_serve_interrupt(&GPTD1);
  OSAL_IRQ_EPILOGUE();
}
#endif /* KINETIS_GPT_USE_PIT0 */

#if KINETIS_GPT_USE_PIT1
/**
 * @brief   PIT1 interrupt handler.
 *
 * @isr
 */
OSAL_IRQ_HANDLER(KINETIS_PIT1_IRQ_VECTOR) {
  OSAL_IRQ_PROLOGUE();
  gpt_lld_serve_interrupt(&GPTD2);
  OSAL_IRQ_EPILOGUE();
}
#endif /* KINETIS_GPT_USE_PIT1 */

#if KINETIS_GPT_USE_PIT2
/**
 * @brief   PIT2 interrupt handler.
 *
 * @isr
 */
OSAL_IRQ_HANDLER(KINETIS_PIT2_IRQ_VECTOR) {
  OSAL_IRQ_PROLOGUE();
  gpt_lld_serve_interrupt(&GPTD3);
  OSAL_IRQ_EPILOGUE();
}
#endif /* KINETIS_GPT_USE_PIT2 */

#if KINETIS_GPT_USE_PIT3
/**
 * @brief   PIT3 interrupt handler.
 *
 * @isr
 */
OSAL_IRQ_HANDLER(KINETIS_PIT3_IRQ_VECTOR) {
  OSAL_IRQ_PROLOGUE();
  gpt_lld_serve_interrupt(&GPTD4);
  OSAL_IRQ_EPILOGUE();
}
#endif /* KINETIS_GPT_USE_PIT3 */

#else /* !KINETIS_HAS_PIT_COMMON_IRQ */
/**
 * @brief   Common PIT interrupt handler.
 *
 * @isr
 */
OSAL_IRQ_HANDLER(KINETIS_PIT_IRQ_VECTOR) {
  OSAL_IRQ_PROLOGUE();
#if KINETIS_GPT_USE_PIT0
  if(GPTD1.channel->TFLG & PIT_TFLGn_TIF)
    gpt_lld_serve_interrupt(&GPTD1);
#endif /* KINETIS_GPT_USE_PIT0 */
#if KINETIS_GPT_USE_PIT1
  if(GPTD2.channel->TFLG & PIT_TFLGn_TIF)
    gpt_lld_serve_interrupt(&GPTD2);
#endif /* KINETIS_GPT_USE_PIT1 */
#if KINETIS_GPT_USE_PIT2
  if(GPTD3.channel->TFLG & PIT_TFLGn_TIF)
    gpt_lld_serve_interrupt(&GPTD3);
#endif /* KINETIS_GPT_USE_PIT2 */
#if KINETIS_GPT_USE_PIT3
  if(GPTD4.channel->TFLG & PIT_TFLGn_TIF)
    gpt_lld_serve_interrupt(&GPTD4);
#endif /* KINETIS_GPT_USE_PIT3 */
  OSAL_IRQ_EPILOGUE();
}

#endif /* !KINETIS_HAS_PIT_COMMON_IRQ */

/*===========================================================================*/
/* Driver exported functions.                                                */
/*===========================================================================*/

/**
 * @brief   Low level GPT driver initialization.
 *
 * @notapi
 */
void gpt_lld_init(void) {

#if KINETIS_GPT_USE_PIT0
  /* Driver initialization.*/
  GPTD1.channel = &PIT->CHANNEL[0];
  gptObjectInit(&GPTD1);
#endif

#if KINETIS_GPT_USE_PIT1
  /* Driver initialization.*/
  GPTD2.channel = &PIT->CHANNEL[1];
  gptObjectInit(&GPTD2);
#endif

#if KINETIS_GPT_USE_PIT2
  /* Driver initialization.*/
  GPTD3.channel =  &PIT->CHANNEL[2];
  gptObjectInit(&GPTD3);
#endif

#if KINETIS_GPT_USE_PIT3
  /* Driver initialization.*/
  GPTD4.channel =  &PIT->CHANNEL[3];
  gptObjectInit(&GPTD4);
#endif
}

/**
 * @brief   Configures and activates the GPT peripheral.
 *
 * @param[in] gptp      pointer to the @p GPTDriver object
 *
 * @notapi
 */
void gpt_lld_start(GPTDriver *gptp) {
  uint16_t psc;

  if (gptp->state == GPT_STOP) {
    /* Clock activation.*/
    SIM->SCGC6 |= SIM_SCGC6_PIT;
    gptp->clock = KINETIS_SYSCLK_FREQUENCY;

#if !KINETIS_HAS_PIT_COMMON_IRQ

#if KINETIS_GPT_USE_PIT0
    if (&GPTD1 == gptp) {
      nvicEnableVector(PITChannel0_IRQn, KINETIS_GPT_PIT0_IRQ_PRIORITY);
    }
#endif
#if KINETIS_GPT_USE_PIT1
    if (&GPTD2 == gptp) {
      nvicEnableVector(PITChannel1_IRQn, KINETIS_GPT_PIT1_IRQ_PRIORITY);
    }
#endif
#if KINETIS_GPT_USE_PIT2
    if (&GPTD3 == gptp) {
      nvicEnableVector(PITChannel2_IRQn, KINETIS_GPT_PIT2_IRQ_PRIORITY);
    }
#endif
#if KINETIS_GPT_USE_PIT3
    if (&GPTD4 == gptp) {
      nvicEnableVector(PITChannel3_IRQn, KINETIS_GPT_PIT3_IRQ_PRIORITY);
    }
#endif

#else /* !KINETIS_HAS_PIT_COMMON_IRQ */
    nvicEnableVector(PIT_IRQn, KINETIS_GPT_PIT_IRQ_PRIORITY);
    active_channels++;
#endif /* !KINETIS_HAS_PIT_COMMON_IRQ */
  }

  /* Prescaler value calculation.*/
  psc = (uint16_t)((gptp->clock / gptp->config->frequency) - 1);
  osalDbgAssert(((uint32_t)(psc + 1) * gptp->config->frequency) == gptp->clock,
                "invalid frequency");

  /* Enable the PIT */
  PIT->MCR = 0;
}

/**
 * @brief   Deactivates the GPT peripheral.
 *
 * @param[in] gptp      pointer to the @p GPTDriver object
 *
 * @notapi
 */
void gpt_lld_stop(GPTDriver *gptp) {

  if (gptp->state == GPT_READY) {
    SIM->SCGC6 &= ~SIM_SCGC6_PIT;

    /* Disable the channel */
    gptp->channel->TCTRL = 0;

    /* Clear pending interrupts */
    gptp->channel->TFLG |= PIT_TFLGn_TIF;

#if !KINETIS_HAS_PIT_COMMON_IRQ

#if KINETIS_GPT_USE_PIT0
    if (&GPTD1 == gptp) {
      nvicDisableVector(PITChannel0_IRQn);
    }
#endif
#if KINETIS_GPT_USE_PIT1
    if (&GPTD2 == gptp) {
      nvicDisableVector(PITChannel1_IRQn);
    }
#endif
#if KINETIS_GPT_USE_PIT2
    if (&GPTD3 == gptp) {
      nvicDisableVector(PITChannel2_IRQn);
    }
#endif
#if KINETIS_GPT_USE_PIT3
    if (&GPTD4 == gptp) {
      nvicDisableVector(PITChannel3_IRQn);
    }
#endif

#else /* !KINETIS_HAS_PIT_COMMON_IRQ */
    if(--active_channels == 0)
      nvicDisableVector(PIT_IRQn);
#endif /* !KINETIS_HAS_PIT_COMMON_IRQ */
  }
}

/**
 * @brief   Starts the timer in continuous mode.
 *
 * @param[in] gptp      pointer to the @p GPTDriver object
 * @param[in] interval  period in ticks
 *
 * @notapi
 */
void gpt_lld_start_timer(GPTDriver *gptp, gptcnt_t interval) {

  /* Clear pending interrupts */
  gptp->channel->TFLG |= PIT_TFLGn_TIF;

  /* Set the interval */
  gpt_lld_change_interval(gptp, interval);

  /* Start the timer */
  gptp->channel->TCTRL |= PIT_TCTRLn_TIE | PIT_TCTRLn_TEN;
}

/**
 * @brief   Stops the timer.
 *
 * @param[in] gptp      pointer to the @p GPTDriver object
 *
 * @notapi
 */
void gpt_lld_stop_timer(GPTDriver *gptp) {

  /* Stop the timer */
  gptp->channel->TCTRL = 0;
}

/**
 * @brief   Starts the timer in one shot mode and waits for completion.
 * @details This function specifically polls the timer waiting for completion
 *          in order to not have extra delays caused by interrupt servicing,
 *          this function is only recommended for short delays.
 *
 * @param[in] gptp      pointer to the @p GPTDriver object
 * @param[in] interval  time interval in ticks
 *
 * @notapi
 */
void gpt_lld_polled_delay(GPTDriver *gptp, gptcnt_t interval) {
  struct PIT_CHANNEL *channel = gptp->channel;

  /* Disable timer and disable interrupts */
  channel->TCTRL = 0;

  /* Clear the interrupt flag */
  channel->TFLG |= PIT_TFLGn_TIF;

  /* Set the interval */
  channel->LDVAL = (gptp->clock / gptp->config->frequency) * interval;

  /* Enable Timer but keep interrupts disabled */
  channel->TCTRL = PIT_TCTRLn_TEN;

  /* Wait for the interrupt flag to be set */
  while (!(channel->TFLG & PIT_TFLGn_TIF))
    ;

  /* Disable timer and disable interrupts */
  channel->TCTRL = 0;
}

#endif /* HAL_USE_GPT */

/** @} */