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
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
|
/*This file has been prepared for Doxygen automatic documentation generation.*/
/*! \file *********************************************************************
*
* \brief FreeRTOS port header for AVR32 UC3.
*
* - Compiler: IAR EWAVR32
* - Supported devices: All AVR32 devices can be used.
* - AppNote:
*
* \author Atmel Corporation: http://www.atmel.com \n
* Support and FAQ: http://support.atmel.no/
*
*****************************************************************************/
/*
FreeRTOS.org V5.1.2 - Copyright (C) 2003-2009 Richard Barry.
This file is part of the FreeRTOS.org distribution.
FreeRTOS.org is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
FreeRTOS.org is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with FreeRTOS.org; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
A special exception to the GPL can be applied should you wish to distribute
a combined work that includes FreeRTOS.org, without being obliged to provide
the source code for any proprietary components. See the licensing section
of http://www.FreeRTOS.org for full details of how and when the exception
can be applied.
***************************************************************************
***************************************************************************
* *
* Get the FreeRTOS eBook! See http://www.FreeRTOS.org/Documentation *
* *
* This is a concise, step by step, 'hands on' guide that describes both *
* general multitasking concepts and FreeRTOS specifics. It presents and *
* explains numerous examples that are written using the FreeRTOS API. *
* Full source code for all the examples is provided in an accompanying *
* .zip file. *
* *
***************************************************************************
***************************************************************************
Please ensure to read the configuration and relevant port sections of the
online documentation.
http://www.FreeRTOS.org - Documentation, latest information, license and
contact details.
http://www.SafeRTOS.com - A version that is certified for use in safety
critical systems.
http://www.OpenRTOS.com - Commercial support, development, porting,
licensing and training services.
*/
#ifndef PORTMACRO_H
#define PORTMACRO_H
/*-----------------------------------------------------------
* Port specific definitions.
*
* The settings in this file configure FreeRTOS correctly for the
* given hardware and compiler.
*
* These settings should not be altered.
*-----------------------------------------------------------
*/
#include <avr32/io.h>
#include "intc.h"
#include "compiler.h"
#ifdef __cplusplus
extern "C" {
#endif
/* Type definitions. */
#define portCHAR char
#define portFLOAT float
#define portDOUBLE double
#define portLONG long
#define portSHORT short
#define portSTACK_TYPE unsigned portLONG
#define portBASE_TYPE portLONG
#define TASK_DELAY_MS(x) ( (x) /portTICK_RATE_MS )
#define TASK_DELAY_S(x) ( (x)*1000 /portTICK_RATE_MS )
#define TASK_DELAY_MIN(x) ( (x)*60*1000/portTICK_RATE_MS )
#define configTICK_TC_IRQ ATPASTE2(AVR32_TC_IRQ, configTICK_TC_CHANNEL)
#if( configUSE_16_BIT_TICKS == 1 )
typedef unsigned portSHORT portTickType;
#define portMAX_DELAY ( portTickType ) 0xffff
#else
typedef unsigned portLONG portTickType;
#define portMAX_DELAY ( portTickType ) 0xffffffff
#endif
/*-----------------------------------------------------------*/
/* Architecture specifics. */
#define portSTACK_GROWTH ( -1 )
#define portTICK_RATE_MS ( ( portTickType ) 1000 / configTICK_RATE_HZ )
#define portBYTE_ALIGNMENT 4
#define portNOP() {__asm__ __volatile__ ("nop");}
/*-----------------------------------------------------------*/
/*-----------------------------------------------------------*/
/* INTC-specific. */
#define DISABLE_ALL_EXCEPTIONS() Disable_global_exception()
#define ENABLE_ALL_EXCEPTIONS() Enable_global_exception()
#define DISABLE_ALL_INTERRUPTS() Disable_global_interrupt()
#define ENABLE_ALL_INTERRUPTS() Enable_global_interrupt()
#define DISABLE_INT_LEVEL(int_lev) Disable_interrupt_level(int_lev)
#define ENABLE_INT_LEVEL(int_lev) Enable_interrupt_level(int_lev)
/*
* Debug trace.
* Activated if and only if configDBG is nonzero.
* Prints a formatted string to stdout.
* The current source file name and line number are output with a colon before
* the formatted string.
* A carriage return and a linefeed are appended to the output.
* stdout is redirected to the USART configured by configDBG_USART.
* The parameters are the same as for the standard printf function.
* There is no return value.
* SHALL NOT BE CALLED FROM WITHIN AN INTERRUPT as fputs and printf use malloc,
* which is interrupt-unsafe with the current __malloc_lock and __malloc_unlock.
*/
#if configDBG
#define portDBG_TRACE(...) \
{ \
fputs(__FILE__ ":" ASTRINGZ(__LINE__) ": ", stdout); \
printf(__VA_ARGS__); \
fputs("\r\n", stdout); \
}
#else
#define portDBG_TRACE(...)
#endif
/* Critical section management. */
#define portDISABLE_INTERRUPTS() DISABLE_ALL_INTERRUPTS()
#define portENABLE_INTERRUPTS() ENABLE_ALL_INTERRUPTS()
extern void vPortEnterCritical( void );
extern void vPortExitCritical( void );
#define portENTER_CRITICAL() vPortEnterCritical();
#define portEXIT_CRITICAL() vPortExitCritical();
/* Added as there is no such function in FreeRTOS. */
extern void *pvPortRealloc( void *pv, size_t xSize );
/*-----------------------------------------------------------*/
/*=============================================================================================*/
/*
* Restore Context for cases other than INTi.
*/
#define portRESTORE_CONTEXT() \
{ \
extern volatile unsigned portLONG ulCriticalNesting; \
extern volatile void *volatile pxCurrentTCB; \
\
__asm__ __volatile__ ( \
/* Set SP to point to new stack */ \
"mov r8, LWRD("ASTRINGZ(pxCurrentTCB)") \n\t"\
"orh r8, HWRD("ASTRINGZ(pxCurrentTCB)") \n\t"\
"ld.w r0, r8[0] \n\t"\
"ld.w sp, r0[0] \n\t"\
\
/* Restore ulCriticalNesting variable */ \
"ld.w r0, sp++ \n\t"\
"mov r8, LWRD("ASTRINGZ(ulCriticalNesting)") \n\t"\
"orh r8, HWRD("ASTRINGZ(ulCriticalNesting)") \n\t"\
"st.w r8[0], r0 \n\t"\
\
/* Restore R0..R7 */ \
"ldm sp++, r0-r7 \n\t"\
/* R0-R7 should not be used below this line */ \
/* Skip PC and SR (will do it at the end) */ \
"sub sp, -2*4 \n\t"\
/* Restore R8..R12 and LR */ \
"ldm sp++, r8-r12, lr \n\t"\
/* Restore SR */ \
"ld.w r0, sp[-8*4] \n\t" /* R0 is modified, is restored later. */\
"mtsr "ASTRINGZ(AVR32_SR)", r0 \n\t"\
/* Restore r0 */ \
"ld.w r0, sp[-9*4] \n\t"\
/* Restore PC */ \
"ld.w pc, sp[-7*4]" /* Get PC from stack - PC is the 7th register saved */ \
); \
\
/* Force import of global symbols from assembly */ \
ulCriticalNesting; \
pxCurrentTCB; \
}
/*
* portSAVE_CONTEXT_INT() and portRESTORE_CONTEXT_INT(): for INT0..3 exceptions.
* portSAVE_CONTEXT_SCALL() and portRESTORE_CONTEXT_SCALL(): for the scall exception.
*
* Had to make different versions because registers saved on the system stack
* are not the same between INT0..3 exceptions and the scall exception.
*/
// Task context stack layout:
// R8 (*)
// R9 (*)
// R10 (*)
// R11 (*)
// R12 (*)
// R14/LR (*)
// R15/PC (*)
// SR (*)
// R0
// R1
// R2
// R3
// R4
// R5
// R6
// R7
// ulCriticalNesting
// (*) automatically done for INT0..INT3, but not for SCALL
/*
* The ISR used for the scheduler tick depends on whether the cooperative or
* the preemptive scheduler is being used.
*/
#if configUSE_PREEMPTION == 0
/*
* portSAVE_CONTEXT_OS_INT() for OS Tick exception.
*/
#define portSAVE_CONTEXT_OS_INT() \
{ \
/* Save R0..R7 */ \
__asm__ __volatile__ ("stm --sp, r0-r7"); \
\
/* With the cooperative scheduler, as there is no context switch by interrupt, */ \
/* there is also no context save. */ \
}
/*
* portRESTORE_CONTEXT_OS_INT() for Tick exception.
*/
#define portRESTORE_CONTEXT_OS_INT() \
{ \
__asm__ __volatile__ ( \
/* Restore R0..R7 */ \
"ldm sp++, r0-r7 \n\t"\
\
/* With the cooperative scheduler, as there is no context switch by interrupt, */ \
/* there is also no context restore. */ \
"rete" \
); \
}
#else
/*
* portSAVE_CONTEXT_OS_INT() for OS Tick exception.
*/
#define portSAVE_CONTEXT_OS_INT() \
{ \
extern volatile unsigned portLONG ulCriticalNesting; \
extern volatile void *volatile pxCurrentTCB; \
\
/* When we come here */ \
/* Registers R8..R12, LR, PC and SR had already been pushed to system stack */ \
\
__asm__ __volatile__ ( \
/* Save R0..R7 */ \
"stm --sp, r0-r7 \n\t"\
\
/* Save ulCriticalNesting variable - R0 is overwritten */ \
"mov r8, LWRD("ASTRINGZ(ulCriticalNesting)") \n\t"\
"orh r8, HWRD("ASTRINGZ(ulCriticalNesting)") \n\t"\
"ld.w r0, r8[0] \n\t"\
"st.w --sp, r0 \n\t"\
\
/* Check if INT0 or higher were being handled (case where the OS tick interrupted another */ \
/* interrupt handler (which was of a higher priority level but decided to lower its priority */ \
/* level and allow other lower interrupt level to occur). */ \
/* In this case we don't want to do a task switch because we don't know what the stack */ \
/* currently looks like (we don't know what the interrupted interrupt handler was doing). */ \
/* Saving SP in pxCurrentTCB and then later restoring it (thinking restoring the task) */ \
/* will just be restoring the interrupt handler, no way!!! */ \
/* So, since we won't do a vTaskSwitchContext(), it's of no use to save SP. */ \
"ld.w r0, sp[9*4] \n\t" /* Read SR in stack */\
"bfextu r0, r0, 22, 3 \n\t" /* Extract the mode bits to R0. */\
"cp.w r0, 1 \n\t" /* Compare the mode bits with supervisor mode(b'001) */\
"brhi LABEL_INT_SKIP_SAVE_CONTEXT_"ASTRINGZ(__LINE__)" \n\t"\
\
/* Store SP in the first member of the structure pointed to by pxCurrentTCB */ \
/* NOTE: we don't enter a critical section here because all interrupt handlers */ \
/* MUST perform a SAVE_CONTEXT/RESTORE_CONTEXT in the same way as */ \
/* portSAVE_CONTEXT_OS_INT/port_RESTORE_CONTEXT_OS_INT if they call OS functions. */ \
/* => all interrupt handlers must use portENTER_SWITCHING_ISR/portEXIT_SWITCHING_ISR. */ \
"mov r8, LWRD("ASTRINGZ(pxCurrentTCB)") \n\t"\
"orh r8, HWRD("ASTRINGZ(pxCurrentTCB)") \n\t"\
"ld.w r0, r8[0] \n\t"\
"st.w r0[0], sp \n"\
\
"LABEL_INT_SKIP_SAVE_CONTEXT_"ASTRINGZ(__LINE__)":" \
); \
}
/*
* portRESTORE_CONTEXT_OS_INT() for Tick exception.
*/
#define portRESTORE_CONTEXT_OS_INT() \
{ \
extern volatile unsigned portLONG ulCriticalNesting; \
extern volatile void *volatile pxCurrentTCB; \
\
/* Check if INT0 or higher were being handled (case where the OS tick interrupted another */ \
/* interrupt handler (which was of a higher priority level but decided to lower its priority */ \
/* level and allow other lower interrupt level to occur). */ \
/* In this case we don't want to do a task switch because we don't know what the stack */ \
/* currently looks like (we don't know what the interrupted interrupt handler was doing). */ \
/* Saving SP in pxCurrentTCB and then later restoring it (thinking restoring the task) */ \
/* will just be restoring the interrupt handler, no way!!! */ \
__asm__ __volatile__ ( \
"ld.w r0, sp[9*4] \n\t" /* Read SR in stack */\
"bfextu r0, r0, 22, 3 \n\t" /* Extract the mode bits to R0. */\
"cp.w r0, 1 \n\t" /* Compare the mode bits with supervisor mode(b'001) */\
"brhi LABEL_INT_SKIP_RESTORE_CONTEXT_"ASTRINGZ(__LINE__) \
); \
\
/* Else */ \
/* because it is here safe, always call vTaskSwitchContext() since an OS tick occurred. */ \
/* A critical section has to be used here because vTaskSwitchContext handles FreeRTOS linked lists. */\
portENTER_CRITICAL(); \
vTaskSwitchContext(); \
portEXIT_CRITICAL(); \
\
/* Restore all registers */ \
\
__asm__ __volatile__ ( \
/* Set SP to point to new stack */ \
"mov r8, LWRD("ASTRINGZ(pxCurrentTCB)") \n\t"\
"orh r8, HWRD("ASTRINGZ(pxCurrentTCB)") \n\t"\
"ld.w r0, r8[0] \n\t"\
"ld.w sp, r0[0] \n"\
\
"LABEL_INT_SKIP_RESTORE_CONTEXT_"ASTRINGZ(__LINE__)": \n\t"\
\
/* Restore ulCriticalNesting variable */ \
"ld.w r0, sp++ \n\t"\
"mov r8, LWRD("ASTRINGZ(ulCriticalNesting)") \n\t"\
"orh r8, HWRD("ASTRINGZ(ulCriticalNesting)") \n\t"\
"st.w r8[0], r0 \n\t"\
\
/* Restore R0..R7 */ \
"ldm sp++, r0-r7 \n\t"\
\
/* Now, the stack should be R8..R12, LR, PC and SR */ \
"rete" \
); \
\
/* Force import of global symbols from assembly */ \
ulCriticalNesting; \
pxCurrentTCB; \
}
#endif
/*
* portSAVE_CONTEXT_SCALL() for SupervisorCALL exception.
*
* NOTE: taskYIELD()(== SCALL) MUST NOT be called in a mode > supervisor mode.
*
*/
#define portSAVE_CONTEXT_SCALL() \
{ \
extern volatile unsigned portLONG ulCriticalNesting; \
extern volatile void *volatile pxCurrentTCB; \
\
/* Warning: the stack layout after SCALL doesn't match the one after an interrupt. */ \
/* If SR[M2:M0] == 001 */ \
/* PC and SR are on the stack. */ \
/* Else (other modes) */ \
/* Nothing on the stack. */ \
\
/* WARNING NOTE: the else case cannot happen as it is strictly forbidden to call */ \
/* vTaskDelay() and vTaskDelayUntil() OS functions (that result in a taskYield()) */ \
/* in an interrupt|exception handler. */ \
\
__asm__ __volatile__ ( \
/* in order to save R0-R7 */ \
"sub sp, 6*4 \n\t"\
/* Save R0..R7 */ \
"stm --sp, r0-r7 \n\t"\
\
/* in order to save R8-R12 and LR */ \
/* do not use SP if interrupts occurs, SP must be left at bottom of stack */ \
"sub r7, sp,-16*4 \n\t"\
/* Copy PC and SR in other places in the stack. */ \
"ld.w r0, r7[-2*4] \n\t" /* Read SR */\
"st.w r7[-8*4], r0 \n\t" /* Copy SR */\
"ld.w r0, r7[-1*4] \n\t" /* Read PC */\
"st.w r7[-7*4], r0 \n\t" /* Copy PC */\
\
/* Save R8..R12 and LR on the stack. */ \
"stm --r7, r8-r12, lr \n\t"\
\
/* Arriving here we have the following stack organizations: */ \
/* R8..R12, LR, PC, SR, R0..R7. */ \
\
/* Now we can finalize the save. */ \
\
/* Save ulCriticalNesting variable - R0 is overwritten */ \
"mov r8, LWRD("ASTRINGZ(ulCriticalNesting)") \n\t"\
"orh r8, HWRD("ASTRINGZ(ulCriticalNesting)") \n\t"\
"ld.w r0, r8[0] \n\t"\
"st.w --sp, r0" \
); \
\
/* Disable the its which may cause a context switch (i.e. cause a change of */ \
/* pxCurrentTCB). */ \
/* Basically, all accesses to the pxCurrentTCB structure should be put in a */ \
/* critical section because it is a global structure. */ \
portENTER_CRITICAL(); \
\
/* Store SP in the first member of the structure pointed to by pxCurrentTCB */ \
__asm__ __volatile__ ( \
"mov r8, LWRD("ASTRINGZ(pxCurrentTCB)") \n\t"\
"orh r8, HWRD("ASTRINGZ(pxCurrentTCB)") \n\t"\
"ld.w r0, r8[0] \n\t"\
"st.w r0[0], sp" \
); \
}
/*
* portRESTORE_CONTEXT() for SupervisorCALL exception.
*/
#define portRESTORE_CONTEXT_SCALL() \
{ \
extern volatile unsigned portLONG ulCriticalNesting; \
extern volatile void *volatile pxCurrentTCB; \
\
/* Restore all registers */ \
\
/* Set SP to point to new stack */ \
__asm__ __volatile__ ( \
"mov r8, LWRD("ASTRINGZ(pxCurrentTCB)") \n\t"\
"orh r8, HWRD("ASTRINGZ(pxCurrentTCB)") \n\t"\
"ld.w r0, r8[0] \n\t"\
"ld.w sp, r0[0]" \
); \
\
/* Leave pxCurrentTCB variable access critical section */ \
portEXIT_CRITICAL(); \
\
__asm__ __volatile__ ( \
/* Restore ulCriticalNesting variable */ \
"ld.w r0, sp++ \n\t"\
"mov r8, LWRD("ASTRINGZ(ulCriticalNesting)") \n\t"\
"orh r8, HWRD("ASTRINGZ(ulCriticalNesting)") \n\t"\
"st.w r8[0], r0 \n\t"\
\
/* skip PC and SR */ \
/* do not use SP if interrupts occurs, SP must be left at bottom of stack */ \
"sub r7, sp, -10*4 \n\t"\
/* Restore r8-r12 and LR */ \
"ldm r7++, r8-r12, lr \n\t"\
\
/* RETS will take care of the extra PC and SR restore. */ \
/* So, we have to prepare the stack for this. */ \
"ld.w r0, r7[-8*4] \n\t" /* Read SR */\
"st.w r7[-2*4], r0 \n\t" /* Copy SR */\
"ld.w r0, r7[-7*4] \n\t" /* Read PC */\
"st.w r7[-1*4], r0 \n\t" /* Copy PC */\
\
/* Restore R0..R7 */ \
"ldm sp++, r0-r7 \n\t"\
\
"sub sp, -6*4 \n\t"\
\
"rets" \
); \
\
/* Force import of global symbols from assembly */ \
ulCriticalNesting; \
pxCurrentTCB; \
}
/*
* The ISR used depends on whether the cooperative or
* the preemptive scheduler is being used.
*/
#if configUSE_PREEMPTION == 0
/*
* ISR entry and exit macros. These are only required if a task switch
* is required from the ISR.
*/
#define portENTER_SWITCHING_ISR() \
{ \
/* Save R0..R7 */ \
__asm__ __volatile__ ("stm --sp, r0-r7"); \
\
/* With the cooperative scheduler, as there is no context switch by interrupt, */ \
/* there is also no context save. */ \
}
/*
* Input parameter: in R12, boolean. Perform a vTaskSwitchContext() if 1
*/
#define portEXIT_SWITCHING_ISR() \
{ \
__asm__ __volatile__ ( \
/* Restore R0..R7 */ \
"ldm sp++, r0-r7 \n\t"\
\
/* With the cooperative scheduler, as there is no context switch by interrupt, */ \
/* there is also no context restore. */ \
"rete" \
); \
}
#else
/*
* ISR entry and exit macros. These are only required if a task switch
* is required from the ISR.
*/
#define portENTER_SWITCHING_ISR() \
{ \
extern volatile unsigned portLONG ulCriticalNesting; \
extern volatile void *volatile pxCurrentTCB; \
\
/* When we come here */ \
/* Registers R8..R12, LR, PC and SR had already been pushed to system stack */ \
\
__asm__ __volatile__ ( \
/* Save R0..R7 */ \
"stm --sp, r0-r7 \n\t"\
\
/* Save ulCriticalNesting variable - R0 is overwritten */ \
"mov r8, LWRD("ASTRINGZ(ulCriticalNesting)") \n\t"\
"orh r8, HWRD("ASTRINGZ(ulCriticalNesting)") \n\t"\
"ld.w r0, r8[0] \n\t"\
"st.w --sp, r0 \n\t"\
\
/* Check if INT0 or higher were being handled (case where the OS tick interrupted another */ \
/* interrupt handler (which was of a higher priority level but decided to lower its priority */ \
/* level and allow other lower interrupt level to occur). */ \
/* In this case we don't want to do a task switch because we don't know what the stack */ \
/* currently looks like (we don't know what the interrupted interrupt handler was doing). */ \
/* Saving SP in pxCurrentTCB and then later restoring it (thinking restoring the task) */ \
/* will just be restoring the interrupt handler, no way!!! */ \
/* So, since we won't do a vTaskSwitchContext(), it's of no use to save SP. */ \
"ld.w r0, sp[9*4] \n\t" /* Read SR in stack */\
"bfextu r0, r0, 22, 3 \n\t" /* Extract the mode bits to R0. */\
"cp.w r0, 1 \n\t" /* Compare the mode bits with supervisor mode(b'001) */\
"brhi LABEL_ISR_SKIP_SAVE_CONTEXT_"ASTRINGZ(__LINE__)" \n\t"\
\
/* Store SP in the first member of the structure pointed to by pxCurrentTCB */ \
"mov r8, LWRD("ASTRINGZ(pxCurrentTCB)") \n\t"\
"orh r8, HWRD("ASTRINGZ(pxCurrentTCB)") \n\t"\
"ld.w r0, r8[0] \n\t"\
"st.w r0[0], sp \n"\
\
"LABEL_ISR_SKIP_SAVE_CONTEXT_"ASTRINGZ(__LINE__)":" \
); \
}
/*
* Input parameter: in R12, boolean. Perform a vTaskSwitchContext() if 1
*/
#define portEXIT_SWITCHING_ISR() \
{ \
extern volatile unsigned portLONG ulCriticalNesting; \
extern volatile void *volatile pxCurrentTCB; \
\
__asm__ __volatile__ ( \
/* Check if INT0 or higher were being handled (case where the OS tick interrupted another */ \
/* interrupt handler (which was of a higher priority level but decided to lower its priority */ \
/* level and allow other lower interrupt level to occur). */ \
/* In this case it's of no use to switch context and restore a new SP because we purposedly */ \
/* did not previously save SP in its TCB. */ \
"ld.w r0, sp[9*4] \n\t" /* Read SR in stack */\
"bfextu r0, r0, 22, 3 \n\t" /* Extract the mode bits to R0. */\
"cp.w r0, 1 \n\t" /* Compare the mode bits with supervisor mode(b'001) */\
"brhi LABEL_ISR_SKIP_RESTORE_CONTEXT_"ASTRINGZ(__LINE__)" \n\t"\
\
/* If a switch is required then we just need to call */ \
/* vTaskSwitchContext() as the context has already been */ \
/* saved. */ \
"cp.w r12, 1 \n\t" /* Check if Switch context is required. */\
"brne LABEL_ISR_RESTORE_CONTEXT_"ASTRINGZ(__LINE__)":C" \
); \
\
/* A critical section has to be used here because vTaskSwitchContext handles FreeRTOS linked lists. */\
portENTER_CRITICAL(); \
vTaskSwitchContext(); \
portEXIT_CRITICAL(); \
\
__asm__ __volatile__ ( \
"LABEL_ISR_RESTORE_CONTEXT_"ASTRINGZ(__LINE__)": \n\t"\
/* Restore the context of which ever task is now the highest */ \
/* priority that is ready to run. */ \
\
/* Restore all registers */ \
\
/* Set SP to point to new stack */ \
"mov r8, LWRD("ASTRINGZ(pxCurrentTCB)") \n\t"\
"orh r8, HWRD("ASTRINGZ(pxCurrentTCB)") \n\t"\
"ld.w r0, r8[0] \n\t"\
"ld.w sp, r0[0] \n"\
\
"LABEL_ISR_SKIP_RESTORE_CONTEXT_"ASTRINGZ(__LINE__)": \n\t"\
\
/* Restore ulCriticalNesting variable */ \
"ld.w r0, sp++ \n\t"\
"mov r8, LWRD("ASTRINGZ(ulCriticalNesting)") \n\t"\
"orh r8, HWRD("ASTRINGZ(ulCriticalNesting)") \n\t"\
"st.w r8[0], r0 \n\t"\
\
/* Restore R0..R7 */ \
"ldm sp++, r0-r7 \n\t"\
\
/* Now, the stack should be R8..R12, LR, PC and SR */ \
"rete" \
); \
\
/* Force import of global symbols from assembly */ \
ulCriticalNesting; \
pxCurrentTCB; \
}
#endif
#define portYIELD() {__asm__ __volatile__ ("scall");}
/* Task function macros as described on the FreeRTOS.org WEB site. */
#define portTASK_FUNCTION_PROTO( vFunction, pvParameters ) void vFunction( void *pvParameters )
#define portTASK_FUNCTION( vFunction, pvParameters ) void vFunction( void *pvParameters )
#ifdef __cplusplus
}
#endif
#endif /* PORTMACRO_H */
|
