/* isr.h * * This include file contains all the constants and structures associated * with the management of processor interrupt levels. This handler * supports interrupt critical sections, vectoring of user interrupt * handlers, nesting of interrupts, and manipulating interrupt levels. * * COPYRIGHT (c) 1989-1999. * On-Line Applications Research Corporation (OAR). * * The license and distribution terms for this file may be * found in the file LICENSE in this distribution or at * http://www.rtems.com/license/LICENSE. * * $Id$ */ #ifndef __ISR_h #define __ISR_h #ifdef __cplusplus extern "C" { #endif /* * The following type defines the control block used to manage * the interrupt level portion of the status register. */ typedef uint32_t ISR_Level; /* * The following type defines the type used to manage the vectors. */ typedef uint32_t ISR_Vector_number; /* * Return type for ISR Handler */ typedef void ISR_Handler; /* * Pointer to an ISR Handler */ #if (CPU_ISR_PASSES_FRAME_POINTER == 1) typedef ISR_Handler ( *ISR_Handler_entry )( ISR_Vector_number, CPU_Interrupt_frame * ); #else typedef ISR_Handler ( *ISR_Handler_entry )( ISR_Vector_number ); #endif /* * This constant promotes out the number of vectors truly supported by * the current CPU being used. This is usually the number of distinct vectors * the cpu can vector. */ #define ISR_NUMBER_OF_VECTORS CPU_INTERRUPT_NUMBER_OF_VECTORS /* * This constant promotes out the highest valid interrupt vector number. */ #define ISR_INTERRUPT_MAXIMUM_VECTOR_NUMBER CPU_INTERRUPT_MAXIMUM_VECTOR_NUMBER /* * The following is TRUE if signals have been sent to the currently * executing thread by an ISR handler. */ SCORE_EXTERN boolean _ISR_Signals_to_thread_executing; /* * The following contains the interrupt service routine nest level. * When this variable is zero, a thread is executing. */ SCORE_EXTERN volatile uint32_t _ISR_Nest_level; /* * The following declares the Vector Table. Application * interrupt service routines are vectored by the ISR Handler via this table. */ SCORE_EXTERN ISR_Handler_entry *_ISR_Vector_table; /* * _ISR_Handler_initialization * * DESCRIPTION: * * This routine performs the initialization necessary for this handler. */ void _ISR_Handler_initialization ( void ); /* * _ISR_Disable * * DESCRIPTION: * * This routine disables all interrupts so that a critical section * of code can be executing without being interrupted. Upon return, * the argument _level will contain the previous interrupt mask level. */ #define _ISR_Disable( _level ) \ _CPU_ISR_Disable( _level ) /* * _ISR_Enable * * DESCRIPTION: * * This routine enables interrupts to the previous interrupt mask * LEVEL. It is used at the end of a critical section of code to * enable interrupts so they can be processed again. */ #define _ISR_Enable( _level ) \ _CPU_ISR_Enable( _level ) /* * _ISR_Flash * * DESCRIPTION: * * This routine temporarily enables interrupts to the previous * interrupt mask level and then disables all interrupts so that * the caller can continue into the second part of a critical * section. This routine is used to temporarily enable interrupts * during a long critical section. It is used in long sections of * critical code when a point is reached at which interrupts can * be temporarily enabled. Deciding where to flash interrupts * in a long critical section is often difficult and the point * must be selected with care to insure that the critical section * properly protects itself. */ #define _ISR_Flash( _level ) \ _CPU_ISR_Flash( _level ) /* * _ISR_Install_vector * * DESCRIPTION: * * This routine installs new_handler as the interrupt service routine * for the specified vector. The previous interrupt service routine is * returned as old_handler. */ #define _ISR_Install_vector( _vector, _new_handler, _old_handler ) \ _CPU_ISR_install_vector( _vector, _new_handler, _old_handler ) /* * _ISR_Get_level * * DESCRIPTION: * * This routine returns the current interrupt level. */ #define _ISR_Get_level() \ _CPU_ISR_Get_level() /* * _ISR_Set_level * * DESCRIPTION: * * This routine sets the current interrupt level to that specified * by new_level. The new interrupt level is effective when the * routine exits. */ #define _ISR_Set_level( _new_level ) \ _CPU_ISR_Set_level( _new_level ) /* * _ISR_Handler * * DESCRIPTION: * * This routine is the interrupt dispatcher. ALL interrupts * are vectored to this routine so that minimal context can be saved * and setup performed before the application's high-level language * interrupt service routine is invoked. After the application's * interrupt service routine returns control to this routine, it * will determine if a thread dispatch is necessary. If so, it will * insure that the necessary thread scheduling operations are * performed when the outermost interrupt service routine exits. * * NOTE: Implemented in assembly language. */ void _ISR_Handler( void ); /* * _ISR_Dispatch * * DESCRIPTION: * * This routine provides a wrapper so that the routine * _Thread_Dispatch can be invoked when a reschedule is necessary * at the end of the outermost interrupt service routine. This * wrapper is necessary to establish the processor context needed * by _Thread_Dispatch and to save the processor context which is * corrupted by _Thread_Dispatch. This context typically consists * of registers which are not preserved across routine invocations. * * NOTE: Implemented in assembly language. */ void _ISR_Dispatch( void ); /*PAGE * * _ISR_Is_in_progress * * DESCRIPTION: * * This function returns TRUE if the processor is currently servicing * and interrupt and FALSE otherwise. A return value of TRUE indicates * that the caller is an interrupt service routine, NOT a thread. The */ #if (CPU_PROVIDES_ISR_IS_IN_PROGRESS == TRUE) boolean _ISR_Is_in_progress( void ); #else #define _ISR_Is_in_progress() \ (_ISR_Nest_level != 0) #endif #include #ifdef __cplusplus } #endif #endif /* end of include file */