sam7fc/include/rtos/context.h

#ifndef _CONTEXT_H_
#define _CONTEXT_H_

#include <stdint.h>
#include "rtos/spinlock.h"

struct register_context {
	uint32_t r0;
	uint32_t r1;
	uint32_t pc;
	uint32_t cpsr;
	uint32_t r2;
	uint32_t r3;
	uint32_t r4;
	uint32_t r5;
	uint32_t r6;
	uint32_t r7;
	uint32_t r8;
	uint32_t r9;
	uint32_t r10;
	uint32_t r11;
	uint32_t r12;
	uint32_t sp;
	uint32_t r14;
};

enum ctx_state {
	CONTEXT_NULL = 0,
	CONTEXT_RUNNING = 1,
	CONTEXT_READY = 2,
	CONTEXT_INTERRUPTED = 3,
	CONTEXT_SLEEP = 4,
	CONTEXT_SLEEP_QUEUE = 5,
};

struct context {
	/* regs *MUST* be first in struct! */
	struct register_context regs;
	void *stack;
	uint8_t state;
	uint8_t priority;

	/* next pointers for run & sleep queues */
	struct context *run_queue;
	struct context *sleep_queue;
};

extern struct context *current_context;

void isr_context_yield(void);
void context_yield(void);

uint8_t isr_context_wait(struct spinlock *lock);
uint8_t context_wait(struct spinlock *lock);
uint8_t context_wait_queue(struct spinlock *lock, struct context **queue);
uint8_t context_wait_pri_queue(struct spinlock *lock, struct context **queue);

void isr_context_signal(struct context *c);
void context_signal(struct context *c);
uint32_t context_signal_queue(struct context **queue);

void isr_context_interrupt(struct context *c);
void context_interrupt(struct context *c);
uint32_t context_interrupt_queue(struct context *c, struct context **queue);

struct context * create_ctx(uint32_t stacksize, uint8_t priority, void (* code)(void *arg), void *arg);

void init_context(void);

#endif /* _CONTEXT_H_ */