cpu_status.h

日本著名的的嵌入式实时操作系统T-Kernel的源码及用户手册。

/*
 *----------------------------------------------------------------------
 *    T-Kernel
 *
 *    Copyright (C) 2004 by Ken Sakamura. All rights reserved.
 *    T-Kernel is distributed under the T-License.
 *----------------------------------------------------------------------
 *
 *    Version:   1.01.00
 *    Released by T-Engine Forum(http://www.t-engine.org) at 2004/6/28.
 *
 *----------------------------------------------------------------------
 */

/*
 *	cpu_status.h (VR4131)
 *	CPU-Dependent Definition
 */

#ifndef _CPU_STATUS_
#define _CPU_STATUS_

#include <tk/syslib.h>
#include <tk/sysdef.h>
#include "cpu_insn.h"

/*
 * Start/End critical section
 */
#define	BEGIN_CRITICAL_SECTION	{ UINT _psr_ = disint();
#define END_CRITICAL_SECTION	enaint(_psr_); }

/*
 * Start/End interrupt disable section
 */
#define	BEGIN_DISABLE_INTERRUPT	{ UINT _psr_ = disint();
#define	END_DISABLE_INTERRUPT	enaint(_psr_); }

/*
 * Interrupt enable/disable
 */
#define	ENABLE_INTERRUPT	{ enaint(0); }
#define	DISABLE_INTERRUPT	{ disint(); }

/*
 * Enable interrupt nesting
 *	Enable the interrupt that has a higher priority than 'level.'
 */
#define	ENABLE_INTERRUPT_UPTO(level)	{ enaint(0); }

/*
 * Move to/Restore task independent part
 */
#define	ENTER_TASK_INDEPENDENT	{ EnterTaskIndependent(); }
#define	LEAVE_TASK_INDEPENDENT	{ LeaveTaskIndependent(); }

/* ----------------------------------------------------------------------- */
/*
 *	Check system state
 */

/*
 * When a system call is called from task independent part, TRUE
 */
#define	in_indp()	( isTaskIndependent() || ctxtsk == NULL )

/*
 * When a system call is called during dispatch disable, TRUE
 * Also include the task independent part as during dispatch disable.
 */
#define	in_ddsp()	( isDispatchDisabled()	\
			|| in_indp()		\
			|| isDI(~getPSR()) )

/*
 * When a system call is called during CPU lock (interrupt disable), TRUE
 * Also include the task independent part as during CPU lock.
 */
#define	in_loc()	( isDI(~getPSR())	\
			|| in_indp() )

/*
 * When a system call is called during executing the quasi task part, TRUE
 * Valid only when in_indp() == FALSE because it is not discriminated
 * from the task independent part.
 */
#define	in_qtsk()	( ctxtsk->sysmode > ctxtsk->isysmode )

/* ----------------------------------------------------------------------- */
/*
 *	Task dispatcher startup routine
 */

/*
 * Request for task dispatcher startup
 *	Use IP1 software interrupt as the delayed interrupt. 
 */
Inline void dispatch_request( void )
{
	UW	occ;

	Asm("mfc0 %0, $13": "=r"(occ));
	occ |= OC_IP(1);
	Asm("mtc0 %0, $13":: "r"(occ));
}

/*
 * Throw away the current task context.
 * and forcibly dispatch to the task that should be performed next.
 *	Use at system startup and 'tk_ext_tsk, tk_exd_tsk.'
 */
Inline void force_dispatch( void )
{
IMPORT	void	dispatch_to_schedtsk();

	Asm("jr %0":: "r"(&dispatch_to_schedtsk));
}

/*
 * Start task dispatcher
 *	Do not use 'dispatch()' because of using the delayed interrupt.
 */
#define	dispatch()

/* ----------------------------------------------------------------------- */
/*
 *	Task exception
 */

/*
 * Task exception handler startup reservation
 */
IMPORT void request_tex( TCB *tcb );

/* ----------------------------------------------------------------------- */

/*
 * Task context block
 */
typedef struct {
	DW	ssp;		/* System stack pointer */
	VP	uatb;		/* Task space page table */
	INT	lsid;		/* Task space ID */
} CTXB;

/*
 * CPU information
 */
IMPORT ATR	available_cop;	/* Enabled coprocessor (TA_COPn) */

/*
 * User defined handler call
 */
IMPORT INT CallUserHandler( INT p1, INT p2, INT p3, FP hdr, VP gp );

#endif /* _CPU_STATUS_ */