aboutsummaryrefslogtreecommitdiffstats
path: root/src/gos/raw32.c
blob: 5a65ea86191c92ead90d1935ae3f0d0dcfa2ae9a (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
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
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
/*
 * This file is subject to the terms of the GFX License. If a copy of
 * the license was not distributed with this file, you can obtain one at:
 *
 *              http://ugfx.org/license.html
 */

/**
 * @file    src/gos/raw32.c
 * @brief   GOS Raw (bare metal) support.
 */
#include "gfx.h"

#if GFX_USE_OS_RAW32

#include <string.h>				// Prototype for memcpy()

#if GOS_RAW_HEAP_SIZE != 0
	static void _gosHeapInit(void);
#else
	#define _gosHeapInit()
#endif
static void _gosThreadsInit(void);

/*********************************************************
 * Initialise
 *********************************************************/

void _gosInit(void) {
	// Set up the heap allocator
	_gosHeapInit();

	// Start the scheduler
	_gosThreadsInit();
}

/*********************************************************
 * For WIn32 emulation - automatically add the tick functions
 * the user would normally have to provide for bare metal.
 *********************************************************/

#if defined(WIN32)
	#undef Red
	#undef Green
	#undef Blue
	#define WIN32_LEAN_AND_MEAN
	#include <stdio.h>
	#include <windows.h>
	systemticks_t gfxSystemTicks(void)						{ return GetTickCount(); }
	systemticks_t gfxMillisecondsToTicks(delaytime_t ms)	{ return ms; }
#endif

/*********************************************************
 * Exit everything functions
 *********************************************************/

void gfxHalt(const char *msg) {
	#if defined(WIN32)
		fprintf(stderr, "%s\n", msg);
		ExitProcess(1);
	#else
		volatile uint32_t	dummy;
		(void)				msg;

		while(1)
			dummy++;
	#endif
}

void gfxExit(void) {
	#if defined(WIN32)
		ExitProcess(0);
	#else
		volatile uint32_t	dummy;

		while(1)
			dummy++;
	#endif
}

/*********************************************************
 * Head allocation functions
 *********************************************************/

#if GOS_RAW_HEAP_SIZE == 0
	#include <stdlib.h>				// Prototype for malloc(), realloc() and free()

	void *gfxAlloc(size_t sz) {
		return malloc(sz);
	}

	void *gfxRealloc(void *ptr, size_t oldsz, size_t newsz) {
		(void) oldsz;
		return realloc(ptr, newsz);
	}

	void gfxFree(void *ptr) {
		free(ptr);
	}

#else

	// Slot structure - user memory follows
	typedef struct memslot {
		struct memslot *next;		// The next memslot
		size_t			sz;			// Includes the size of this memslot.
		} memslot;

	// Free Slot - immediately follows the memslot structure
	typedef struct freeslot {
		memslot *nextfree;			// The next free slot
	} freeslot;

	#define GetSlotSize(sz)		((((sz) + (sizeof(freeslot) - 1)) & ~(sizeof(freeslot) - 1)) + sizeof(memslot))
	#define NextFree(pslot)		((freeslot *)Slot2Ptr(pslot))->nextfree
	#define Ptr2Slot(p)			((memslot *)(p) - 1)
	#define Slot2Ptr(pslot)		((pslot)+1)

	static memslot *			firstSlot;
	static memslot *			lastSlot;
	static memslot *			freeSlots;
	static char					heap[GOS_RAW_HEAP_SIZE];

	static void _gosHeapInit(void) {
		lastSlot = 0;
		gfxAddHeapBlock(heap, GOS_RAW_HEAP_SIZE);
	}

	void gfxAddHeapBlock(void *ptr, size_t sz) {
		if (sz < sizeof(memslot)+sizeof(freeslot))
			return;

		if (lastSlot)
			lastSlot->next = (memslot *)ptr;
		else
			firstSlot = lastSlot = freeSlots = (memslot *)ptr;

		lastSlot->next = 0;
		lastSlot->sz = sz;
		NextFree(lastSlot) = 0;
	}

	void *gfxAlloc(size_t sz) {
		register memslot *prev, *p, *new;

		if (!sz) return 0;
		sz = GetSlotSize(sz);
		for (prev = 0, p = freeSlots; p != 0; prev = p, p = NextFree(p)) {
			// Loop till we have a block big enough
			if (p->sz < sz)
				continue;
			// Can we save some memory by splitting this block?
			if (p->sz >= sz + sizeof(memslot)+sizeof(freeslot)) {
				new = (memslot *)((char *)p + sz);
				new->next = p->next;
				p->next = new;
				new->sz = p->sz - sz;
				p->sz = sz;
				if (lastSlot == p)
					lastSlot = new;
				NextFree(new) = NextFree(p);
				NextFree(p) = new;
			}
			// Remove it from the free list
			if (prev)
				NextFree(prev) = NextFree(p);
			else
				freeSlots = NextFree(p);
			// Return the result found
			return Slot2Ptr(p);
		}
		// No slots large enough
		return 0;
	}

	void *gfxRealloc(void *ptr, size_t oldsz, size_t sz) {
		register memslot *prev, *p, *new;
		(void) oldsz;

		if (!ptr)
			return gfxAlloc(sz);
		if (!sz) {
			gfxFree(ptr);
			return 0;
		}

		p = Ptr2Slot(ptr);
		sz = GetSlotSize(sz);

		// If the next slot is free (and contiguous) merge it into this one
		if ((char *)p + p->sz == (char *)p->next) {
			for (prev = 0, new = freeSlots; new != 0; prev = new, new = NextFree(new)) {
				if (new == p->next) {
					p->next = new->next;
					p->sz += new->sz;
					if (prev)
						NextFree(prev) = NextFree(new);
					else
						freeSlots = NextFree(new);
					if (lastSlot == new)
						lastSlot = p;
					break;
				}
			}
		}

		// If this block is large enough we are nearly done
		if (sz < p->sz) {
			// Can we save some memory by splitting this block?
			if (p->sz >= sz + sizeof(memslot)+sizeof(freeslot)) {
				new = (memslot *)((char *)p + sz);
				new->next = p->next;
				p->next = new;
				new->sz = p->sz - sz;
				p->sz = sz;
				if (lastSlot == p)
					lastSlot = new;
				NextFree(new) = freeSlots;
				freeSlots = new;
			}
			return Slot2Ptr(p);
		}

		// We need to do this the hard way
		if ((new = gfxAlloc(sz)))
			return 0;
		memcpy(new, ptr, p->sz - sizeof(memslot));
		gfxFree(ptr);
		return new;
	}

	void gfxFree(void *ptr) {
		register memslot *prev, *p, *new;

		if (!ptr)
			return;

		p = Ptr2Slot(ptr);

		// If the next slot is free (and contiguous) merge it into this one
		if ((char *)p + p->sz == (char *)p->next) {
			for (prev = 0, new = freeSlots; new != 0; prev = new, new = NextFree(new)) {
				if (new == p->next) {
					p->next = new->next;
					p->sz += new->sz;
					if (prev)
						NextFree(prev) = NextFree(new);
					else
						freeSlots = NextFree(new);
					if (lastSlot == new)
						lastSlot = p;
					break;
				}
			}
		}

		// Add it into the free chain
		NextFree(p) = freeSlots;
		freeSlots = p;
	}
#endif

/*********************************************************
 * Semaphores and critical region functions
 *********************************************************/

#if !defined(INTERRUPTS_OFF) || !defined(INTERRUPTS_ON)
	#define INTERRUPTS_OFF()
	#define INTERRUPTS_ON()
#endif

void gfxSystemLock(void) {
	INTERRUPTS_OFF();
}

void gfxSystemUnlock(void) {
	INTERRUPTS_ON();
}

void gfxMutexInit(gfxMutex *pmutex) {
	pmutex[0] = 0;
}

void gfxMutexEnter(gfxMutex *pmutex) {
	INTERRUPTS_OFF();
	while (pmutex[0]) {
		INTERRUPTS_ON();
		gfxYield();
		INTERRUPTS_OFF();
	}
	pmutex[0] = 1;
	INTERRUPTS_ON();
}

void gfxMutexExit(gfxMutex *pmutex) {
	pmutex[0] = 0;
}

void gfxSemInit(gfxSem *psem, semcount_t val, semcount_t limit) {
	psem->cnt = val;
	psem->limit = limit;
}

bool_t gfxSemWait(gfxSem *psem, delaytime_t ms) {
	systemticks_t	starttm, delay;

	// Convert our delay to ticks
	switch (ms) {
	case TIME_IMMEDIATE:
		delay = TIME_IMMEDIATE;
		break;
	case TIME_INFINITE:
		delay = TIME_INFINITE;
		break;
	default:
		delay = gfxMillisecondsToTicks(ms);
		if (!delay) delay = 1;
		starttm = gfxSystemTicks();
	}

	INTERRUPTS_OFF();
	while (psem->cnt <= 0) {
		INTERRUPTS_ON();
		// Check if we have exceeded the defined delay
		switch (delay) {
		case TIME_IMMEDIATE:
			return FALSE;
		case TIME_INFINITE:
			break;
		default:
			if (gfxSystemTicks() - starttm >= delay)
				return FALSE;
			break;
		}
		gfxYield();
		INTERRUPTS_OFF();
	}
	psem->cnt--;
	INTERRUPTS_ON();
	return TRUE;
}

void gfxSemSignal(gfxSem *psem) {
	INTERRUPTS_OFF();
	gfxSemSignalI(psem);
	INTERRUPTS_ON();
}

void gfxSemSignalI(gfxSem *psem) {
	if (psem->cnt < psem->limit)
		psem->cnt++;
}

/*********************************************************
 * Sleep functions
 *********************************************************/

void gfxSleepMilliseconds(delaytime_t ms) {
	systemticks_t	starttm, delay;

	// Safety first
	switch (ms) {
	case TIME_IMMEDIATE:
		return;
	case TIME_INFINITE:
		while(1)
			gfxYield();
		return;
	}

	// Convert our delay to ticks
	delay = gfxMillisecondsToTicks(ms);
	starttm = gfxSystemTicks();

	do {
		gfxYield();
	} while (gfxSystemTicks() - starttm < delay);
}

void gfxSleepMicroseconds(delaytime_t ms) {
	systemticks_t	starttm, delay;

	// Safety first
	switch (ms) {
	case TIME_IMMEDIATE:
		return;
	case TIME_INFINITE:
		while(1)
			gfxYield();
		return;
	}

	// Convert our delay to ticks
	delay = gfxMillisecondsToTicks(ms/1000);
	starttm = gfxSystemTicks();

	do {
		gfxYield();
	} while (gfxSystemTicks() - starttm < delay);
}

/*********************************************************
 * Threading functions
 *********************************************************/

/**
 * There are some compilers we know how they store the jmpbuf. For those
 * we can use the constant macro definitions. For others we have to "auto-detect".
 * Auto-detection is hairy and there is no guarantee it will work on all architectures.
 * For those it doesn't - read the compiler manuals and the library source code to
 * work out the correct macro values.
 * You can use the debugger to work out the values for your compiler and put them here.
 * Defining these macros as constant values makes the system behaviour guaranteed but also
 * makes your code compiler and cpu architecture dependant.
 */
#if 0
	// Define your compiler constant values here.
	//	These example values are for mingw32 compiler (x86).
	#define AUTO_DETECT_MASK	FALSE
	#define STACK_DIR_UP		FALSE
	#define MASK1				0x00000011
	#define MASK2				0x00000000
	#define STACK_BASE			9
#else
	#define AUTO_DETECT_MASK	TRUE
	#define STACK_DIR_UP		stackdirup			// TRUE if the stack grow up instead of down
	#define MASK1				jmpmask1			// The 1st mask of jmp_buf elements that need relocation
	#define MASK2				jmpmask2			// The 2nd mask of jmp_buf elements that need relocation
	#define STACK_BASE			stackbase			// The base of the stack frame relative to the local variables
	static bool_t		stackdirup;
	static uint32_t		jmpmask1;
	static uint32_t		jmpmask2;
	static size_t		stackbase;
#endif

#include <setjmp.h> /* jmp_buf, setjmp(), longjmp() */

/**
 * Some compilers define a _setjmp() and a setjmp().
 * The difference between them is that setjmp() saves the signal masks.
 * That is of no use to us so prefer to use the _setjmp() methods.
 * If they don't exist compile them to be the standard setjmp() function.
 * Similarly for longjmp().
 */
#ifndef setjmp
	#ifndef _setjmp
		#define _setjmp setjmp
	#endif
#endif
#ifndef longjmp
	#ifndef _longjmp
		#define _longjmp longjmp
	#endif
#endif

typedef struct thread {
	struct thread *	next;					// Next thread
	int				flags;					// Flags
		#define FLG_THD_ALLOC	0x0001
		#define FLG_THD_MAIN	0x0002
		#define FLG_THD_DEAD	0x0004
		#define FLG_THD_WAIT	0x0008
	size_t			size;					// Size of the thread stack (including this structure)
	threadreturn_t	(*fn)(void *param);		// Thread function
	void *			param;					// Parameter for the thread function
	jmp_buf			cxt;					// The current thread context.
} thread;

typedef struct threadQ {
	thread *head;
	thread *tail;
} threadQ;

static threadQ		readyQ;					// The list of ready threads
static threadQ		deadQ;					// Where we put threads waiting to be deallocated
static thread *		current;				// The current running thread
static thread		mainthread;				// The main thread context

static void Qinit(threadQ * q) {
	q->head = q->tail = 0;
}

static void Qadd(threadQ * q, thread *t) {
	t->next = 0;
	if (q->head) {
		q->tail->next = t;
		q->tail = t;
	} else
		q->head = q->tail = t;
}

static thread *Qpop(threadQ * q) {
	struct thread * t;

	if (!q->head)
		return 0;
	t = q->head;
	q->head = t->next;
	return t;
}

#if AUTO_DETECT_MASK
	// The structure for the saved stack frame information
	typedef struct saveloc {
		char *		localptr;
		jmp_buf		cxt;
	} saveloc;

	// A pointer to our auto-detection buffer.
	static saveloc	*pframeinfo;

	/* These functions are not static to prevent the compiler removing them as functions */

	void get_stack_state(void) {
		char c;
		pframeinfo->localptr = (char *)&c;
		_setjmp(pframeinfo->cxt);
	}

	void get_stack_state_in_fn(void) {
		pframeinfo++;
		get_stack_state();
		pframeinfo--;
	}
#endif

static void _gosThreadsInit(void) {
	Qinit(&readyQ);
	current = &mainthread;
	current->next = 0;
	current->size = sizeof(thread);
	current->flags = FLG_THD_MAIN;
	current->fn = 0;
	current->param = 0;

	#if AUTO_DETECT_MASK
		{
			uint32_t	i;
			char **		pout;
			char **		pin;
			size_t		diff;
			char *		framebase;

			// Allocate a buffer to store our test data
			pframeinfo = (saveloc *)gfxAlloc(sizeof(saveloc)*2);

			// Get details of the stack frame from within a function
			get_stack_state_in_fn();

			// Get details of the stack frame outside the function
			get_stack_state();

			/* Work out the frame entries to relocate by treating the jump buffer as an array of pointers */
			stackdirup =  pframeinfo[1].localptr > pframeinfo[0].localptr;
			pout = (char **)pframeinfo[0].cxt;
			pin =  (char **)pframeinfo[1].cxt;
			diff = pframeinfo[0].localptr - pframeinfo[1].localptr;
			framebase = pframeinfo[0].localptr;
			jmpmask1 = jmpmask2 = 0;
			for (i = 0; i < sizeof(jmp_buf)/sizeof(char *); i++, pout++, pin++) {
				if ((size_t)(*pout - *pin) == diff) {
					if (i < 32)
						jmpmask1 |= 1 << i;
					else
						jmpmask2 |= 1 << (i-32);

					if (stackdirup) {
						if (framebase > *pout)
							framebase = *pout;
					} else {
						if (framebase < *pout)
							framebase = *pout;
					}
				}
			}
			stackbase = stackdirup ? (pframeinfo[0].localptr - framebase) : (framebase - pframeinfo[0].localptr);

			// Clean up
			gfxFree(pframeinfo);
		}
	#endif
}

gfxThreadHandle gfxThreadMe(void) {
	return (gfxThreadHandle)current;
}

void gfxYield(void) {
	if (!_setjmp(current->cxt)) {
		// Add us back to the Queue
		Qadd(&readyQ, current);

		// Check if there are dead processes to deallocate
		while ((current = Qpop(&deadQ)))
			gfxFree(current);

		// Run the next process
		current = Qpop(&readyQ);
		_longjmp(current->cxt, 1);
	}
}

// This routine is not currently public - but it could be.
void gfxThreadExit(threadreturn_t ret) {
	// Save the results
	current->param = (void *)ret;
	current->flags |= FLG_THD_DEAD;

	// Add us to the dead list if we need deallocation as we can't free ourselves.
	// If someone is waiting on the thread they will do the cleanup.
	if ((current->flags & (FLG_THD_ALLOC|FLG_THD_WAIT)) == FLG_THD_ALLOC)
		Qadd(&deadQ, current);

	// Switch to the next task
	current = Qpop(&readyQ);
	if (!current)
		gfxExit();		// Oops - this should never happen!
	_longjmp(current->cxt, 1);
}

gfxThreadHandle gfxThreadCreate(void *stackarea, size_t stacksz, threadpriority_t prio, DECLARE_THREAD_FUNCTION((*fn),p), void *param) {
	thread *	t;
	(void)		prio;

	// Ensure we have a minimum stack size
	if (stacksz < sizeof(thread)+64) {
		stacksz = sizeof(thread)+64;
		stackarea = 0;
	}

	if (stackarea) {
		t = (thread *)stackarea;
		t->flags = 0;
	} else {
		t = (thread *)gfxAlloc(stacksz);
		if (!t)
			return 0;
		t->flags = FLG_THD_ALLOC;
	}
	t->size = stacksz;
	t->fn = fn;
	t->param = param;
	if (_setjmp(t->cxt)) {
		// This is the new thread - call the function!
		gfxThreadExit(current->fn(current->param));

		// We never get here
		return 0;
	}

	// Move the stack frame and relocate the context data
	{
		char **	s;
		char *	nf;
		int		diff;
		uint32_t	i;

		// Copy the stack frame
		#if AUTO_DETECT_MASK
			if (STACK_DIR_UP) {					// Stack grows up
				nf = (char *)(t) + sizeof(thread) + stackbase;
				memcpy(t+1, (char *)&t - stackbase, stackbase+sizeof(char *));
			} else {							// Stack grows down
				nf = (char *)(t) + stacksz - (stackbase + sizeof(char *));
				memcpy(nf, &t, stackbase+sizeof(char *));
			}
		#elif STACK_DIR_UP
			// Stack grows up
			nf = (char *)(t) + sizeof(thread) + stackbase;
			memcpy(t+1, (char *)&t - stackbase, stackbase+sizeof(char *));
		#else
			// Stack grows down
			nf = (char *)(t) + size - (stackbase + sizeof(char *));
			memcpy(nf, &t, stackbase+sizeof(char *));
		#endif

		// Relocate the context data
		s = (char **)(t->cxt);
		diff = nf - (char *)&t;

		// Relocate the elements we know need to be relocated
		for (i = 1; i && i < MASK1; i <<= 1, s++) {
			if ((MASK1 & i))
				*s += diff;
		}
		#ifdef MASK2
			for (i = 1; i && i < MASK2; i <<= 1, s++) {
				if ((MASK1 & i))
					*s += diff;
			}
		#endif
	}

	// Add this thread to the ready queue
	Qadd(&readyQ, t);
	return t;
}

threadreturn_t gfxThreadWait(gfxThreadHandle th) {
	thread *		t;

	t = th;
	if (t == current)
		return -1;

	// Mark that we are waiting
	t->flags |= FLG_THD_WAIT;

	// Wait for the thread to die
	while(!(t->flags & FLG_THD_DEAD))
		gfxYield();

	// Unmark
	t->flags &= ~FLG_THD_WAIT;

	// Clean up resources if needed
	if (t->flags & FLG_THD_ALLOC)
		gfxFree(t);

	// Return the status left by the dead process
	return (threadreturn_t)t->param;
}

#endif /* GFX_USE_OS_RAW32 */