cpu_status.h

uT Kernel os source code for AT91

/*
 *----------------------------------------------------------------------
 *    micro T-Kernel
 *
 *    Copyright (C) 2006-2007 by Ken Sakamura. All rights reserved.
 *    micro T-Kernel is distributed under the micro T-License.
 *----------------------------------------------------------------------
 *
 *    Version:   1.00.00
 *    Released by T-Engine Forum(http://www.t-engine.org) at 2007/03/26.
 *
 *----------------------------------------------------------------------
 */

/*
 *	cpu_status.h (AT91)
 *	AT91M55800A-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 _cpsr_ = disint();
#define END_CRITICAL_SECTION	if ( !isDI(_cpsr_)			\
				  && knl_ctxtsk != knl_schedtsk			\
				  && !knl_isTaskIndependent()		\
				  && !knl_dispatch_disabled ) {		\
					knl_dispatch();			\
				}					\
				enaint(_cpsr_); }

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

/*
 * 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	{ knl_EnterTaskIndependent(); }
#define LEAVE_TASK_INDEPENDENT	{ knl_LeaveTaskIndependent(); }

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

/*
 * When a system call is called from the task independent part, TRUE
 */
#define in_indp()	( knl_isTaskIndependent() || knl_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()	( knl_dispatch_disabled	\
			|| in_indp()		\
			|| isDI(knl_getCPSR()) )

/*
 * 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(knl_getCPSR())		\
			|| 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()	( knl_ctxtsk->sysmode > knl_ctxtsk->isysmode )

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

/*
 * Request for task dispatcher startup
 *	Do nothing at this point because there is no delayed
 *	interrupt function in ARM.
 *	Perform dispatcher startup with END_CRITICAL_SECTION.
 */
#define knl_dispatch_request()	/* */

/*
 * 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 knl_force_dispatch( void )
{
IMPORT	void	knl_dispatch_to_schedtsk();

	Asm("bx %0":: "r"(&knl_dispatch_to_schedtsk));
}

/*
 * Start task dispatcher
 */
Inline void knl_dispatch( void )
{
#if USE_TRAP
	Asm("swi %0":: "i"(SWI_DISPATCH): "lr");
#else
IMPORT void knl_dispatch_entry( void );		/* Dispatcher call */
	knl_dispatch_entry();
#endif
}

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

/*
 * Task context block
 */
typedef struct {
	VP	ssp;		/* System stack pointer */
} CTXB;

#endif /* _CPU_STATUS_ */