1.\" $NetBSD: isr_add.9,v 1.4 1998/09/03 01:54:28 jeremy Exp $ 2.\" 3.\" Copyright (c) 1997 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Jeremy Cooper. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 3. All advertising materials mentioning features or use of this software 18.\" must display the following acknowledgement: 19.\" This product includes software developed by the NetBSD 20.\" Foundation, Inc. and its contributors. 21.\" 4. Neither the name of The NetBSD Foundation nor the names of its 22.\" contributors may be used to endorse or promote products derived 23.\" from this software without specific prior written permission. 24.\" 25.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 26.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS BE 29.\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35.\" POSSIBILITY OF SUCH DAMAGE. 36.\" 37.Dd May 21, 1997 38.Dt ISR_ADD 9 sun3 39.Os NetBSD 40.Sh NAME 41.Nm isr_add , 42.Nm isr_add_autovect , 43.Nm isr_add_vectored , 44.Nm isr_add_custom 45.Nd establish interrupt handler 46.Sh SYNOPSIS 47.Fd #include <sun3/autoconf.h> 48.Bd -literal 49 50typedef int (*isr_func_t)(void *); 51.Ed 52.Ft void 53.Fn isr_add_autovect "isr_func_t fun" "void *arg" "int level" 54.Ft void 55.Fn isr_add_vectored "isr_func_t fun" "void *arg" "int pri" "int vec" 56.Ft void 57.Fn isr_add_custom "int level" "void *fun" 58.Sh DESCRIPTION 59The 60.Nm 61functions establish interrupt handlers into the system interrupt dispatch table 62and are typically called from device drivers during the autoconfiguration 63process. 64.Pp 65There are two types of interrupts in the Motorola 68000 architecture, 66which differ in the way that an interrupt request is mapped to a dispatch 67function within the interrupt vector table. 68.Pp 69When the CPU detects an asserted signal on one of its interrupt request lines, 70it suspends normal instruction execution and begins an interrupt acknowledge 71cycle on the system bus. 72During this cycle the interrupting device directs how the CPU is to dispatch 73its interrupt request. 74.Pp 75If the interrupting device is integrated tightly with the system bus, 76it provides an 8-bit interrupt vector number to the CPU and a 77.Sy vectored 78interrupt occurs. 79This vector number points to a vector entry within the interrupt 80vector table to which instruction execution is immediately transfered. 81.Pp 82If the interrupting device cannot provide a vector number, 83it asserts a specialized bus line and an 84.Sy autovectored 85interrupt occurs. 86The vector number to use is determined by adding the interrupt priority 87.Pq 0\(en6 88to an autovector base 89.Pq typically Li 18 hexadecimal . 90.Pp 91.Bl -tag -width isr_add_autovec 92.It Fn isr_add_autovect 93Adds the function 94.Fa fun 95to the list of interrupt handlers to be called during an autovectored interrupt 96of priority 97.Fa level . 98The pointer 99.Fa arg 100is passed to the function as its first argument. 101.It Fn isr_add_vectored 102Adds the function 103.Fa fun 104to the list of interrupt handlers to be called during a vectored interrupts of 105priority 106.Fa pri 107at dispatch vector number 108.Fa vec . 109The pointer 110.Fa arg 111is passed to the function as its first argument. 112.It Fn isr_add_custom 113Establish function 114.Fa fun 115as the interrupt handler for vector 116.Fa level . 117The autovector base number is automatically added to 118.Fa level . 119.Pp 120.Fa fun 121is called directly as the dispatch handler and must handle all of the specifics 122of saving the processor state and returning from a processor exception. 123These requirements generally dictate that 124.Fa fun 125be written in assembler. 126.El 127.Sh "CODE REFERENCES" 128.Pa sys/arch/sun3/sun3/isr.c 129.Sh "REFERENCES" 130MC68030 User's Manual, Third edition, MC68030UM/AD Rev 2, Motorola Inc. 131.Sh "BUGS" 132There is no way to remove a handler once it has been added. 133