/* $OpenBSD: isr.c,v 1.12 2020/11/24 13:52:40 mpi Exp $ */ /* $NetBSD: isr.c,v 1.5 2000/07/09 08:08:20 nisimura Exp $ */ /*- * Copyright (c) 1996 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Adam Glass, Gordon W. Ross, and Jason R. Thorpe. * * 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. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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. */ /* * Link and dispatch interrupts. */ #include #include #include #include #include #include #include #include isr_autovec_list_t isr_autovec[NISRAUTOVEC]; void isrinit() { int i; /* Initialize the autovector lists. */ for (i = 0; i < NISRAUTOVEC; ++i) { LIST_INIT(&isr_autovec[i]); } } /* * Establish an autovectored interrupt handler. * Called by driver attach functions. */ void isrlink_autovec(int (*func)(void *), void *arg, int ipl, int priority, const char *name) { struct isr_autovec *newisr, *curisr; isr_autovec_list_t *list; #ifdef DIAGNOSTIC if (ipl < 0 || ipl >= NISRAUTOVEC) panic("isrlink_autovec: bad ipl %d", ipl); #endif newisr = (struct isr_autovec *)malloc(sizeof(struct isr_autovec), M_DEVBUF, M_NOWAIT); if (newisr == NULL) panic("isrlink_autovec: can't allocate space for isr"); /* Fill in the new entry. */ newisr->isr_func = func; newisr->isr_arg = arg; newisr->isr_ipl = ipl; newisr->isr_priority = priority; evcount_attach(&newisr->isr_count, name, &newisr->isr_ipl); /* * Some devices are particularly sensitive to interrupt * handling latency. The SCC, for example, can lose many * characters if its interrupt isn't handled with reasonable * speed. * * To work around this problem, each device can give itself a * "priority". An unbuffered SCC would give itself a higher * priority than a SCSI device, for example. * * This solution was originally developed for the hp300, which * has a flat spl scheme (by necessity). Thankfully, the * MVME systems don't have this problem, though this may serve * a useful purpose in any case. */ /* * Get the appropriate ISR list. If the list is empty, no * additional work is necessary; we simply insert ourselves * at the head of the list. */ list = &isr_autovec[ipl]; if (LIST_EMPTY(list)) { LIST_INSERT_HEAD(list, newisr, isr_link); return; } /* * A little extra work is required. We traverse the list * and place ourselves after any ISRs with our current (or * higher) priority. */ for (curisr = LIST_FIRST(list); LIST_NEXT(curisr, isr_link) != NULL; curisr = LIST_NEXT(curisr, isr_link)) { if (newisr->isr_priority > curisr->isr_priority) { LIST_INSERT_BEFORE(curisr, newisr, isr_link); return; } } /* * We're the least important entry, it seems. We just go * on the end. */ LIST_INSERT_AFTER(curisr, newisr, isr_link); } /* * This is the dispatcher called by the low-level * assembly language autovectored interrupt routine. */ void isrdispatch_autovec(int ipl) { struct isr_autovec *isr; isr_autovec_list_t *list; int rc, handled = 0; static int straycount, unexpected; #ifdef DIAGNOSTIC if (ipl < 0 || ipl >= NISRAUTOVEC) panic("isrdispatch_autovec: bad ipl %d", ipl); #endif list = &isr_autovec[ipl]; if (LIST_EMPTY(list)) { printf("isrdispatch_autovec: ipl %d unexpected\n", ipl); if (++unexpected > 10) panic("too many unexpected interrupts"); return; } /* Give all the handlers a chance. */ LIST_FOREACH(isr, list, isr_link) { #ifdef MULTIPROCESSOR if (isr->isr_ipl < IPL_CLOCK) __mp_lock(&kernel_lock); #endif rc = (*isr->isr_func)(isr->isr_arg); #ifdef MULTIPROCESSOR if (isr->isr_ipl < IPL_CLOCK) __mp_unlock(&kernel_lock); #endif if (rc != 0) isr->isr_count.ec_count++; handled |= rc; } if (handled) straycount = 0; else if (++straycount > 50) panic("isr_dispatch_autovec: too many stray interrupts"); else printf("isrdispatch_autovec: stray level %d interrupt\n", ipl); }