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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
*/
#include "gfx.h"
#if GOS_NEED_X_THREADS
/*********************************************************
* 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
starttm = 0;
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;
}
bool_t gfxSemWaitI(gfxSem *psem) {
if (psem->cnt <= 0)
return FALSE;
psem->cnt--;
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
*********************************************************/
/** For each scheduler the following need to be defined...
*
* void _gfxThreadsInit(void); - Initialise the scheduler
* void _gfxStartThread(thread *oldt, thread *newt); - Start a new thread
* void _gfxTaskSwitch(thread *oldt, thread *newt); - Switch to a different thread
*
*/
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
void * 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
#if GFX_CPU == GFX_CPU_UNKNOWN
#include <string.h> // Prototype for memcpy()
#include <setjmp.h>
/**
* 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 we prefer to use the _setjmp() methods.
* If they don't exist compile them to be the standard setjmp() function.
* Similarly for longjmp().
*/
#if (!defined(setjmp) && !defined(_setjmp)) || (GFX_COMPILER == GFX_COMPILER_ARMCC) || (GFX_COMPILER == GFX_COMPILER_KEIL)
#define CXT_SAVE setjmp
#else
#define CXT_SAVE _setjmp
#endif
#if (!defined(longjmp) && !defined(_longjmp)) || (GFX_COMPILER == GFX_COMPILER_ARMCC) || (GFX_COMPILER == GFX_COMPILER_KEIL)
#define CXT_RESTORE longjmp
#else
#define CXT_RESTORE _longjmp
#endif
// A place to store the main thread context.
// All other threads will store the context directly after the thread structure (as part of the stack space).
static jmp_buf maincxt;
/**
* 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 dependent. It also saves a heap of code
* and a few bytes of RAM.
*
* MACROS:
*
* AUTO_DETECT_STACKFRAME TRUE/FALSE - TRUE to auto-detect stack frame structure
* STACK_DIR_UP Macro/bool_t - TRUE if the stack grows up instead of down
* MASK1 Macro/uint32_t - The 1st mask of jmp_buf elements that need relocation
* MASK2 Macro/uint32_t - The 2nd mask of jmp_buf elements that need relocation
* STACK_BASE Macro/size_t - The base of the stack frame relative to the local variables
* _gfxThreadsInit() Macro/Function - Initialise the scheduler
*
*/
#if GFX_COMPILER == GFX_COMPILER_MINGW32
#define AUTO_DETECT_STACKFRAME FALSE
#define STACK_DIR_UP FALSE
#define MASK1 0x00000011
#define MASK2 0x00000000
#define STACK_BASE 12
#define _gfxThreadsInit() mainthread.cxt = maincxt
#else
// Use auto-detection of the stack frame format
// Assumes all the relevant stuff to be relocated is in the first 256 bytes of the jmpbuf.
#define AUTO_DETECT_STACKFRAME 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
// The structure for the saved stack frame information
typedef struct saveloc {
char * localptr;
jmp_buf cxt;
} saveloc;
static bool_t stackdirup;
static uint32_t jmpmask1;
static uint32_t jmpmask2;
static size_t stackbase;
static saveloc *pframeinfo;
// These two functions are not static to prevent the compiler removing them as functions
void _gfxGetStackState(void) {
char *c;
pframeinfo->localptr = (char *)&c;
CXT_SAVE(pframeinfo->cxt);
}
void _gfxGetStackStateInFn(void) {
pframeinfo++;
_gfxGetStackState();
pframeinfo--;
}
static void _gfxThreadsInit(void) {
uint32_t i;
char ** pout;
char ** pin;
size_t diff;
char * framebase;
saveloc tmpsaveloc[2];
// Create the main thread context
mainthread.cxt = maincxt;
// Allocate a buffer to store our test data
pframeinfo = tmpsaveloc;
// Get details of the stack frame from within a function
_gfxGetStackStateInFn();
// Get details of the stack frame outside the function
_gfxGetStackState();
/* 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);
}
#endif
// Move the stack frame and relocate the context data
static void _gfxAdjustCxt(thread *t) {
char ** s;
char * nf;
int diff;
uint32_t i;
// Copy the stack frame
#if AUTO_DETECT_STACKFRAME
if (STACK_DIR_UP) { // Stack grows up
nf = (char *)(t) + sizeof(thread) + sizeof(jmp_buf) + stackbase;
memcpy(t+1, (char *)&s - stackbase, stackbase+sizeof(char *));
} else { // Stack grows down
nf = (char *)(t) + t->size - (stackbase + sizeof(char *));
memcpy(nf, &s, stackbase+sizeof(char *));
}
#elif STACK_DIR_UP
// Stack grows up
nf = (char *)(t) + sizeof(thread) + sizeof(jmp_buf) + stackbase;
memcpy(t+1, (char *)&s - stackbase, stackbase+sizeof(char *));
#else
// Stack grows down
nf = (char *)(t) + t->size - (stackbase + sizeof(char *));
memcpy(nf, &s, stackbase+sizeof(char *));
#endif
// Relocate the context data
s = (char **)(t->cxt);
diff = nf - (char *)&s;
// Relocate the elements we know need to be relocated
for (i = MASK1; i ; i >>= 1, s++) {
if ((i & 1))
*s += diff;
}
#ifdef MASK2
s = (char **)(t->cxt)+32;
for (i = MASK2; i ; i >>= 1, s++) {
if ((i & 1))
*s += diff;
}
#endif
}
static void _gfxXSwitch(thread *oldt, thread *newt, bool_t doBuildFrame) {
// Save the old context
if (CXT_SAVE(oldt->cxt)) return;
// Do we need to build a new context?
if (doBuildFrame) {
// Save our existing context as a starting point for the new context
newt->cxt = newt+1;
if (CXT_SAVE(newt->cxt)) {
// We are now running the new thread
// We can't use any of the above function parameters here
// as we are on a different stack.
// Run the users function.
gfxThreadExit(current->fn(current->param));
// We never get here as gfxThreadExit() never returns
}
// Adjust the new context so the stack references are correct
_gfxAdjustCxt(newt);
}
// Start the new context
CXT_RESTORE(newt->cxt, 1);
}
#define _gfxTaskSwitch(oldt, newt) _gfxXSwitch(oldt, newt, FALSE)
#define _gfxStartThread(oldt, newt) _gfxXSwitch(oldt, newt, TRUE)
#elif GFX_CPU == GFX_CPU_CORTEX_M0 || GFX_CPU == GFX_CPU_CORTEX_M1
// Use the EABI calling standard (ARM's AAPCS) - Save r4 - r11
// The context is saved at the current stack location and a pointer is maintained in the thread structure.
#define _gfxThreadsInit()
static __attribute__((pcs("aapcs"),naked)) void _gfxTaskSwitch(thread *oldt, thread *newt) {
__asm__ volatile ( "push {r4, r5, r6, r7, lr} \n\t"
"mov r4, r8 \n\t"
"mov r5, r9 \n\t"
"mov r6, r10 \n\t"
"mov r7, r11 \n\t"
"push {r4, r5, r6, r7} \n\t"
"str sp, %[oldtcxt] \n\t"
"ldr sp, %[newtcxt] \n\t"
"pop {r4, r5, r6, r7} \n\t"
"mov r8, r4 \n\t"
"mov r9, r5 \n\t"
"mov r10, r6 \n\t"
"mov r11, r7 \n\t"
"pop {r4, r5, r6, r7, pc} \n\t"
: [newtcxt] "=m" (newt->cxt)
: [oldtcxt] "m" (oldt->cxt)
: "memory");
}
static __attribute__((pcs("aapcs"),naked)) void _gfxStartThread(thread *oldt, thread *newt) {
newt->cxt = (char *)newt + newt->size;
__asm__ volatile ( "push {r4, r5, r6, r7, r8, r9, r10, r11, lr} \n\t" // save current context
"str sp, %[oldtcxt] \n\t" // save context pointer
"ldr sp, %[newtcxt] \n\t" // load new context pointer
: [newtcxt] "=m" (newt->cxt)
: [oldtcxt] "m" (oldt->cxt)
: "memory");
// Run the users function
gfxThreadExit(current->fn(current->param));
}
#elif GFX_CPU == GFX_CPU_CORTEX_M3 || GFX_CPU == GFX_CPU_CORTEX_M4 || GFX_CPU == GFX_CPU_CORTEX_M7
// Use the EABI calling standard (ARM's AAPCS) - Save r4 - r11
// The context is saved at the current stack location and a pointer is maintained in the thread structure.
#if CORTEX_USE_FPU
#warning "GOS Threads: You have specified GFX_CPU=GFX_CPU_CORTX_M? with no hardware floating point support but CORTEX_USE_FPU is TRUE. Try using GFX_CPU_GFX_CPU_CORTEX_M?_FP instead"
#endif
#define _gfxThreadsInit()
static __attribute__((pcs("aapcs"),naked)) void _gfxTaskSwitch(thread *oldt, thread *newt) {
__asm__ volatile ( "push {r4, r5, r6, r7, r8, r9, r10, r11, lr} \n\t"
"str sp, %[oldtcxt] \n\t"
"ldr sp, %[newtcxt] \n\t"
"pop {r4, r5, r6, r7, r8, r9, r10, r11, pc} \n\t"
: [newtcxt] "=m" (newt->cxt)
: [oldtcxt] "m" (oldt->cxt)
: "memory");
}
static __attribute__((pcs("aapcs"),naked)) void _gfxStartThread(thread *oldt, thread *newt) {
newt->cxt = (char *)newt + newt->size;
__asm__ volatile ( "push {r4, r5, r6, r7, r8, r9, r10, r11, lr} \n\t"
"str sp, %[oldtcxt] \n\t"
"ldr sp, %[newtcxt] \n\t"
: [newtcxt] "=m" (newt->cxt)
: [oldtcxt] "m" (oldt->cxt)
: "memory");
// Run the users function
gfxThreadExit(current->fn(current->param));
}
#elif GFX_CPU == GFX_CPU == GFX_CPU_CORTEX_M4_FP || GFX_CPU == GFX_CPU_CORTEX_M7_FP
// Use the EABI calling standard (ARM's AAPCS) - Save r4 - r11 and floating point
// The context is saved at the current stack location and a pointer is maintained in the thread structure.
#if !CORTEX_USE_FPU
#warning "GOS Threads: You have specified GFX_CPU=GFX_CPU_CORTX_M?_FP with hardware floating point support but CORTEX_USE_FPU is FALSE. Try using GFX_CPU_GFX_CPU_CORTEX_M? instead"
#endif
#define _gfxThreadsInit()
static __attribute__((pcs("aapcs-vfp"),naked)) void _gfxTaskSwitch(thread *oldt, thread *newt) {
__asm__ volatile ( "push {r4, r5, r6, r7, r8, r9, r10, r11, lr} \n\t"
"vpush {s16-s31} \n\t"
"str sp, %[oldtcxt] \n\t"
"ldr sp, %[newtcxt] \n\t"
"vpop {s16-s31} \n\t"
"pop {r4, r5, r6, r7, r8, r9, r10, r11, pc} \n\t"
: [newtcxt] "=m" (newt->cxt)
: [oldtcxt] "m" (oldt->cxt)
: "memory");
}
static __attribute__((pcs("aapcs-vfp"),naked)) void _gfxStartThread(thread *oldt, thread *newt) {
newt->cxt = (char *)newt + newt->size;
__asm__ volatile ( "push {r4, r5, r6, r7, r8, r9, r10, r11, lr} \n\t"
"vpush {s16-s31} \n\t"
"str sp, %[oldtcxt] \n\t"
"ldr sp, %[newtcxt] \n\t"
: [newtcxt] "=m" (newt->cxt)
: [oldtcxt] "m" (oldt->cxt)
: "memory");
// Run the users function
gfxThreadExit(current->fn(current->param));
}
#else
#error "GOS Threads: Unsupported Scheduler. Try setting GFX_CPU = GFX_CPU_UNKNOWN"
#endif
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;
}
void _gosThreadsInit(void) {
Qinit(&readyQ);
mainthread.next = 0;
mainthread.size = sizeof(thread);
mainthread.flags = FLG_THD_MAIN;
mainthread.fn = 0;
mainthread.param = 0;
_gfxThreadsInit();
current = &mainthread;
}
gfxThreadHandle gfxThreadMe(void) {
return (gfxThreadHandle)current;
}
// Check if there are dead processes to deallocate
static void cleanUpDeadThreads(void) {
thread *p;
while ((p = Qpop(&deadQ)))
gfxFree(p);
}
void gfxYield(void) {
thread *me;
// Clean up zombies
cleanUpDeadThreads();
// Is there another thread to run?
if (!readyQ.head)
return;
Qadd(&readyQ, me = current);
current = Qpop(&readyQ);
_gfxTaskSwitch(me, current);
}
// This routine is not currently public - but it could be.
void gfxThreadExit(threadreturn_t ret) {
thread *me;
// Save the results in case someone is waiting
me = current;
me->param = (void *)ret;
me->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 ((me->flags & (FLG_THD_ALLOC|FLG_THD_WAIT)) == FLG_THD_ALLOC)
Qadd(&deadQ, me);
// Set the next thread. Exit if it was the last thread
if (!(current = Qpop(&readyQ)))
gfxExit();
// Switch to the new thread
_gfxTaskSwitch(me, current);
// We never get back here as we didn't re-queue ourselves
}
gfxThreadHandle gfxThreadCreate(void *stackarea, size_t stacksz, threadpriority_t prio, DECLARE_THREAD_FUNCTION((*fn),p), void *param) {
thread * t;
thread * me;
(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;
// Add the current thread to the queue because we are starting a new thread.
me = current;
Qadd(&readyQ, me);
current = t;
_gfxStartThread(me, t);
// Return the new thread handle
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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