/* microkernel/task.h */

/*
 * Copyright (c) 1997-2014 Wind River Systems, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1) Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * 2) Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * 3) Neither the name of Wind River Systems nor the names of its contributors
 * may be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef TASK_H
#define TASK_H

#ifdef __cplusplus
extern "C" {
#endif

#include <sections.h>

/*
 * The following task groups are reserved for system use.
 * SysGen automatically generates corresponding TASKGROUPs with reserved
 * GROUPIDs (in the SysGen files SgObjectCount.cpp - TaskGroupIDSetter
 * constructor; and SgSystem.cpp - AddDefaultObjects method).
 * These files must be updated if any changes are made to the reserved groups.
 */

#define EXE_GROUP 1 /* TASKGROUP EXE */
#define USR_GROUP 2 /* TASKGROUP SYS */
#define FPU_GROUP 4 /* TASKGROUP FPU */

extern struct k_task _k_task_list[];

extern void _task_ioctl(ktask_t, int);
extern void _task_group_ioctl(ktask_group_t, int);
extern void task_yield(void);

extern void task_priority_set(ktask_t task, kpriority_t prio);

extern void task_entry_set(ktask_t task, void (*func)(void));
extern void task_abort_handler_set(void (*func)(void));

extern int task_offload_to_fiber(int (*)(), void *);

/*
 * Operations supported by _task_ioctl() and _task_group_ioctl()
 */

#define TASK_START 0
#define TASK_ABORT 1
#define TASK_SUSPEND 2
#define TASK_RESUME 3
#define TASK_BLOCK 4
#define TASK_UNBLOCK 5

#define TASK_GROUP_START 0
#define TASK_GROUP_ABORT 1
#define TASK_GROUP_SUSPEND 2
#define TASK_GROUP_RESUME 3
#define TASK_GROUP_BLOCK 4
#define TASK_GROUP_UNBLOCK 5

extern ktask_t task_id_get();
extern kpriority_t task_priority_get();

#define task_start(t) _task_ioctl(t, TASK_START)
#define task_abort(t) _task_ioctl(t, TASK_ABORT)
#define task_suspend(t) _task_ioctl(t, TASK_SUSPEND)
#define task_resume(t) _task_ioctl(t, TASK_RESUME)

extern uint32_t task_group_mask_get();
extern void task_group_join(uint32_t groups);
extern void task_group_leave(uint32_t groups);

#define task_group_start(g) _task_group_ioctl(g, TASK_GROUP_START)
#define task_group_abort(g) _task_group_ioctl(g, TASK_GROUP_ABORT)
#define task_group_suspend(g) _task_group_ioctl(g, TASK_GROUP_SUSPEND)
#define task_group_resume(g) _task_group_ioctl(g, TASK_GROUP_RESUME)

#define isr_task_id_get() task_id_get()
#define isr_task_priority_get() task_priority_get()
#define isr_task_group_mask_get() task_group_mask_get()

/**
 * @brief Initialize a struct k_task given parameters.
 *
 * @param ident Numeric identifier of this task object.
 * @param priority Priority of task.
 * @param state State of task.
 * @param groups Groups this task belong to.
 * @param fstart Entry function.
 * @param workspace Pointer to workspace (aka, stack).
 * @param worksize Size of workspace.
 * @param fabort Abort function.
 */
#define __K_TASK_INITIALIZER(ident, priority, state, groups, \
			     fstart, workspace, worksize, fabort) \
	{ \
	  NULL, NULL, priority, ident, state, ((groups) ^ SYS), \
	  fstart, workspace, worksize, fabort, NULL, \
	}

/**
 * @brief Define a private microkernel task.
 *
 * This declares and initializes a private task. The new task
 * can be passed to the microkernel task functions.
 *
 * @param name Name of the task.
 * @param priority Priority of task.
 * @param entry Entry function.
 * @param stack_size size of stack (in bytes)
 * @param groups Groups this task belong to.
 */
#define DEFINE_TASK(name, priority, entry, stack_size, groups) \
	extern void entry(void); \
	char __noinit __stack __stack_##name[stack_size]; \
	struct k_task _k_task_obj_##name \
		__section(_k_task_list, private, task) = \
		__K_TASK_INITIALIZER( \
			(ktask_t)&_k_task_obj_##name, \
			priority, 0x00000001, groups, \
			entry, &__stack_##name[0], stack_size, NULL); \
	const ktask_t name = (ktask_t)&_k_task_obj_##name;

#ifdef __cplusplus
}
#endif

#endif /* TASK_H */