aboutsummaryrefslogtreecommitdiffstats
path: root/os/hal/ports/KINETIS/K20x/serial_lld.c
blob: 66d673e043181f8357399ad8ff31265b0bb82b03 (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
/*
    ChibiOS - Copyright (C) 2006..2015 Giovanni Di Sirio

    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    K20x/serial_lld.c
 * @brief   Kinetis K20x Serial Driver subsystem low level driver source.
 *
 * @addtogroup SERIAL
 * @{
 */

#include "osal.h"
#include "hal.h"

#if HAL_USE_SERIAL || defined(__DOXYGEN__)

#include "mk20d5.h"

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

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

/**
 * @brief   SD1 driver identifier.
 */
#if KINETIS_SERIAL_USE_UART0 || defined(__DOXYGEN__)
SerialDriver SD1;
#endif

#if KINETIS_SERIAL_USE_UART1 || defined(__DOXYGEN__)
SerialDriver SD2;
#endif

#if KINETIS_SERIAL_USE_UART2 || defined(__DOXYGEN__)
SerialDriver SD3;
#endif

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

/**
 * @brief   Driver default configuration.
 */
static const SerialConfig default_config = {
  38400
};

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

/**
 * @brief   Common IRQ handler.
 * @note    Tries hard to clear all the pending interrupt sources, we don't
 *          want to go through the whole ISR and have another interrupt soon
 *          after.
 *
 * @param[in] u         pointer to an UART I/O block
 * @param[in] sdp       communication channel associated to the UART
 */
static void serve_interrupt(SerialDriver *sdp) {
  UART_TypeDef *u = sdp->uart;
  uint8_t s1 = u->S1;

  if (s1 & UARTx_S1_RDRF) {
    osalSysLockFromISR();
    if (chIQIsEmptyI(&sdp->iqueue))
      chnAddFlagsI(sdp, CHN_INPUT_AVAILABLE);
    if (chIQPutI(&sdp->iqueue, u->D) < Q_OK)
      chnAddFlagsI(sdp, SD_OVERRUN_ERROR);
    osalSysUnlockFromISR();
  }

  if (s1 & UARTx_S1_TDRE) {
    msg_t b;

    osalSysLockFromISR();
    b = chOQGetI(&sdp->oqueue);
    osalSysUnlockFromISR();

    if (b < Q_OK) {
      osalSysLockFromISR();
      chnAddFlagsI(sdp, CHN_OUTPUT_EMPTY);
      osalSysUnlockFromISR();
      u->C2 &= ~UARTx_C2_TIE;
    } else {
       u->D = b;
    }
  }
}

/**
 * @brief   Attempts a TX preload
 */
static void preload(SerialDriver *sdp) {
  UART_TypeDef *u = sdp->uart;

  if (u->S1 & UARTx_S1_TDRE) {
    msg_t b = chOQGetI(&sdp->oqueue);
    if (b < Q_OK) {
      chnAddFlagsI(sdp, CHN_OUTPUT_EMPTY);
      return;
    }
    u->D = b;
    u->C2 |= UARTx_C2_TIE;
  }
}

/**
 * @brief   Driver output notification.
 */
#if KINETIS_SERIAL_USE_UART0 || defined(__DOXYGEN__)
static void notify1(io_queue_t *qp)
{
  (void)qp;
  preload(&SD1);
}
#endif

#if KINETIS_SERIAL_USE_UART1 || defined(__DOXYGEN__)
static void notify2(io_queue_t *qp)
{
  (void)qp;
  preload(&SD2);
}
#endif

#if KINETIS_SERIAL_USE_UART2 || defined(__DOXYGEN__)
static void notify3(io_queue_t *qp)
{
  (void)qp;
  preload(&SD3);
}
#endif

/**
 * @brief   Common UART configuration.
 *
 */
static void configure_uart(UART_TypeDef *uart, const SerialConfig *config)
{
  uint32_t divisor = (KINETIS_SYSCLK_FREQUENCY * 2 + 1) / config->sc_speed;

  /* Disable UART while configuring */
  uart->C2 &= ~(UARTx_C2_RE | UARTx_C2_TE);
  uart->C1 = 0;

  uart->BDH = UARTx_BDH_SBR(divisor >> 13) | (uart->BDH & ~UARTx_BDH_SBR_MASK);
  uart->BDL = divisor >> 5;
  uart->C4  = UARTx_C4_BRFA(divisor) | (uart->C4 & ~UARTx_C4_BRFA_MASK);

  uart->C2 |= UARTx_C2_RE | UARTx_C2_RIE | UARTx_C2_TE;
  uart->C3 = UARTx_C3_ORIE | UARTx_C3_NEIE | UARTx_C3_FEIE | UARTx_C3_PEIE;
}

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

/* TODO:
 *   UART0_Error is Vector84
 *   UART1_Error is Vector8C
 *   UART2_Error is Vector94
 */

#if KINETIS_SERIAL_USE_UART0 || defined(__DOXYGEN__)
CH_IRQ_HANDLER(Vector80) {

  CH_IRQ_PROLOGUE();
  serve_interrupt(&SD1);
  CH_IRQ_EPILOGUE();
}
#endif

#if KINETIS_SERIAL_USE_UART1 || defined(__DOXYGEN__)
CH_IRQ_HANDLER(Vector88) {

  CH_IRQ_PROLOGUE();
  serve_interrupt(&SD2);
  CH_IRQ_EPILOGUE();
}
#endif

#if KINETIS_SERIAL_USE_UART2 || defined(__DOXYGEN__)
CH_IRQ_HANDLER(Vector90) {

  CH_IRQ_PROLOGUE();
  serve_interrupt(&SD3);
  CH_IRQ_EPILOGUE();
}
#endif

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

/**
 * @brief   Low level serial driver initialization.
 *
 * @notapi
 */
void sd_lld_init(void) {

#if KINETIS_SERIAL_USE_UART0
  /* Driver initialization.*/
  sdObjectInit(&SD1, NULL, notify1);
  SD1.uart = UART0;
#endif

#if KINETIS_SERIAL_USE_UART1
  /* Driver initialization.*/
  sdObjectInit(&SD2, NULL, notify2);
  SD2.uart = UART1;
#endif

#if KINETIS_SERIAL_USE_UART2
  /* Driver initialization.*/
  sdObjectInit(&SD3, NULL, notify3);
  SD3.uart = UART2;
#endif
}

/**
 * @brief   Low level serial driver configuration and (re)start.
 *
 * @param[in] sdp       pointer to a @p SerialDriver object
 * @param[in] config    the architecture-dependent serial driver configuration.
 *                      If this parameter is set to @p NULL then a default
 *                      configuration is used.
 *
 * @notapi
 */
void sd_lld_start(SerialDriver *sdp, const SerialConfig *config) {

  if (config == NULL)
    config = &default_config;

  if (sdp->state == SD_STOP) {
    /* Enables the peripheral.*/

#if KINETIS_SERIAL_USE_UART0
    if (sdp == &SD1) {
      SIM->SCGC4 |= SIM_SCGC4_UART0;
      configure_uart(sdp->uart, config);
      nvicEnableVector(UART0Status_IRQn, KINETIS_SERIAL_UART0_PRIORITY);
    }
#endif /* KINETIS_SERIAL_USE_UART0 */

#if KINETIS_SERIAL_USE_UART1
    if (sdp == &SD2) {
      SIM->SCGC4 |= SIM_SCGC4_UART1;
      configure_uart(sdp->uart, config);
      nvicEnableVector(UART1Status_IRQn, KINETIS_SERIAL_UART1_PRIORITY);
    }
#endif /* KINETIS_SERIAL_USE_UART1 */

#if KINETIS_SERIAL_USE_UART2
    if (sdp == &SD3) {
      SIM->SCGC4 |= SIM_SCGC4_UART2;
      configure_uart(sdp->uart, config);
      nvicEnableVector(UART2Status_IRQn, KINETIS_SERIAL_UART2_PRIORITY);
    }
#endif /* KINETIS_SERIAL_USE_UART2 */

  }
  /* Configures the peripheral.*/

}

/**
 * @brief   Low level serial driver stop.
 * @details De-initializes the USART, stops the associated clock, resets the
 *          interrupt vector.
 *
 * @param[in] sdp       pointer to a @p SerialDriver object
 *
 * @notapi
 */
void sd_lld_stop(SerialDriver *sdp) {

  if (sdp->state == SD_READY) {
    /* TODO: Resets the peripheral.*/

#if KINETIS_SERIAL_USE_UART0
    if (sdp == &SD1) {
      nvicDisableVector(UART0Status_IRQn);
      SIM->SCGC4 &= ~SIM_SCGC4_UART0;
    }
#endif

#if KINETIS_SERIAL_USE_UART1
    if (sdp == &SD2) {
      nvicDisableVector(UART1Status_IRQn);
      SIM->SCGC4 &= ~SIM_SCGC4_UART1;
    }
#endif

#if KINETIS_SERIAL_USE_UART2
    if (sdp == &SD3) {
      nvicDisableVector(UART2Status_IRQn);
      SIM->SCGC4 &= ~SIM_SCGC4_UART2;
    }
#endif
  }
}

#endif /* HAL_USE_SERIAL */

/** @} */