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|
/*
* 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
}
#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, *lastSlot, *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 = freeSlot = (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) = freeSlots;
freeSlots = 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));
free(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 MASK1 and MASK2. 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 MASK values.
* Using the debugger to work out the values for your compiler and putting them here
* also saves a nice block of RAM.
*/
#if 0
#define STACK_DIR_UP FALSE // usually false as most stacks grow down
#define MASK1 somevalue1
#define MASK2 somevalue2 // optional
#define STACK_BASE someindex
#else
#define AUTO_DETECT_MASK TRUE
#define STACK_DIR_UP stackdirup
#define MASK1 jmpmask1
#define MASK2 jmpmask2
#define STACK_BASE 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.
// size - sizeof(thread) bytes of stack follow here
} 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->tail) {
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
static char * lowptr; // A pointer to somewhere low in the stack frame
static char * highptr; // A pointer to somewhere high in the stack frame
// The saved information on a stack frame
typedef struct saveloc {
char * localptr;
jmp_buf cxt;
} saveloc;
static saveloc infn; // The saved stack frame info inside a function
static saveloc outfn; // The saved stack frame info outside a function
static saveloc *saveptr; // Which saved stack frame variable we are currently using
// Where we save all the information
static bool_t stackdirup; // TRUE if the stack grow up instead of down
static uint32_t jmpmask1; // The 1st mask of jmp_buf elements that need relocation
static uint32_t jmpmask2; // The 2nd mask of jmp_buf elements that need relocation
static size_t stackbase; // The base of the stack frame relative to the local variables
/* These functions are not static to prevent the compiler removing them as functions */
void get_highptr(void) {
char c;
highptr = &c;
}
void test_stack(void) {
char c;
saveptr->localptr = (char *)&c;
_setjmp(saveptr->cxt);
get_highptr();
}
void get_stack_state(void) {
char c;
lowptr = &c;
test_stack();
}
void get_stack_state_in_fn(void) {
get_stack_state();
}
#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
// Get details of the stack frame from within a function
saveptr = &infn;
get_stack_state_in_fn();
// Get details of the stack frame outside the function
saveptr = &outfn;
get_stack_state();
/* stack direction */
stackdirup = highptr > lowptr; // Can we also test infn.localptr > outfn.localptr?
/* study the jump buffer */
{
uint32_t i;
char ** pout;
char ** pin;
size_t diff = outfn.localptr - infn.localptr;
char * min_frame = outfn.localptr;
/* following line views jump buffer as array of long int */
pout = (char **)outfn.cxt;
pin = (char **)infn.cxt;
jmpmask1 = jmpmask2 = 0;
if (diff) {
for (i = 0; i < sizeof(jmp_buf)/sizeof(char *); i++, pout++, pin++) {
if ((size_t)(*pout - *pin) == diff) {
/* record frame dependency */
if (i < 32)
jmpmask1 |= 1 << i;
else
jmpmask2 |= 1 << (i-32);
if (stackdirup) {
if (min_frame > *pout) {
min_frame = *pout;
}
} else {
if (min_frame < *pout) {
min_frame = *pout;
}
}
}
}
}
if (stackdirup) {
stackbase = outfn.localptr - min_frame;
} else {
stackbase = min_frame - outfn.localptr;
}
}
#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 */
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