1 /* 2 * Copyright (c) 2003, Matthew Dillon <dillon@backplane.com> All rights reserved. 3 * Copyright (c) 1997, Stefan Esser <se@freebsd.org> All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice unmodified, this list of conditions, and the following 10 * disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 * 26 * $FreeBSD: src/sys/kern/kern_intr.c,v 1.24.2.1 2001/10/14 20:05:50 luigi Exp $ 27 * $DragonFly: src/sys/kern/kern_intr.c,v 1.13 2003/11/03 02:08:35 dillon Exp $ 28 * 29 */ 30 31 #include <sys/param.h> 32 #include <sys/systm.h> 33 #include <sys/malloc.h> 34 #include <sys/kernel.h> 35 #include <sys/sysctl.h> 36 #include <sys/thread.h> 37 #include <sys/proc.h> 38 #include <sys/thread2.h> 39 #include <sys/random.h> 40 41 #include <machine/ipl.h> 42 43 #include <sys/interrupt.h> 44 45 typedef struct intrec { 46 struct intrec *next; 47 inthand2_t *handler; 48 void *argument; 49 const char *name; 50 int intr; 51 } intrec_t; 52 53 static intrec_t *intlists[NHWI+NSWI]; 54 static thread_t ithreads[NHWI+NSWI]; 55 static struct thread ithread_ary[NHWI+NSWI]; 56 static struct random_softc irandom_ary[NHWI+NSWI]; 57 static int irunning[NHWI+NSWI]; 58 59 static void ithread_handler(void *arg); 60 61 thread_t 62 register_swi(int intr, inthand2_t *handler, void *arg, const char *name) 63 { 64 if (intr < NHWI || intr >= NHWI + NSWI) 65 panic("register_swi: bad intr %d", intr); 66 return(register_int(intr, handler, arg, name)); 67 } 68 69 thread_t 70 register_int(int intr, inthand2_t *handler, void *arg, const char *name) 71 { 72 intrec_t **list; 73 intrec_t *rec; 74 thread_t td; 75 76 if (intr < 0 || intr > NHWI + NSWI) 77 panic("register_int: bad intr %d", intr); 78 79 rec = malloc(sizeof(intrec_t), M_DEVBUF, M_NOWAIT); 80 if (rec == NULL) 81 panic("register_swi: malloc failed"); 82 rec->handler = handler; 83 rec->argument = arg; 84 rec->name = name; 85 rec->intr = intr; 86 rec->next = NULL; 87 88 list = &intlists[intr]; 89 90 /* 91 * Create an interrupt thread if necessary, leave it in an unscheduled 92 * state. The kthread restore function exits a critical section before 93 * starting the function so we need *TWO* critical sections in order 94 * for the handler to begin running in one. 95 */ 96 if ((td = ithreads[intr]) == NULL) { 97 lwkt_create((void *)ithread_handler, (void *)intr, &ithreads[intr], 98 &ithread_ary[intr], TDF_STOPREQ|TDF_INTTHREAD, -1, 99 "ithread %d", intr); 100 td = ithreads[intr]; 101 if (intr >= NHWI && intr < NHWI + NSWI) 102 lwkt_setpri(td, TDPRI_SOFT_NORM + TDPRI_CRIT * 2); 103 else 104 lwkt_setpri(td, TDPRI_INT_MED + TDPRI_CRIT * 2); 105 } 106 107 /* 108 * Add the record to the interrupt list 109 */ 110 crit_enter(); /* token */ 111 while (*list != NULL) 112 list = &(*list)->next; 113 *list = rec; 114 crit_exit(); 115 return(td); 116 } 117 118 void 119 unregister_swi(int intr, inthand2_t *handler) 120 { 121 if (intr < NHWI || intr >= NHWI + NSWI) 122 panic("register_swi: bad intr %d", intr); 123 unregister_int(intr, handler); 124 } 125 126 void 127 unregister_int(int intr, inthand2_t handler) 128 { 129 intrec_t **list; 130 intrec_t *rec; 131 132 if (intr < 0 || intr > NHWI + NSWI) 133 panic("register_int: bad intr %d", intr); 134 list = &intlists[intr]; 135 crit_enter(); 136 while ((rec = *list) != NULL) { 137 if (rec->handler == (void *)handler) { 138 *list = rec->next; 139 break; 140 } 141 list = &rec->next; 142 } 143 crit_exit(); 144 if (rec != NULL) { 145 free(rec, M_DEVBUF); 146 } else { 147 printf("warning: unregister_int: int %d handler %p not found\n", 148 intr, handler); 149 } 150 } 151 152 void 153 swi_setpriority(int intr, int pri) 154 { 155 struct thread *td; 156 157 if (intr < NHWI || intr >= NHWI + NSWI) 158 panic("register_swi: bad intr %d", intr); 159 if ((td = ithreads[intr]) != NULL) 160 lwkt_setpri(td, pri); 161 } 162 163 void 164 register_randintr(int intr) 165 { 166 struct random_softc *sc = &irandom_ary[intr]; 167 sc->sc_intr = intr; 168 sc->sc_enabled = 1; 169 } 170 171 void 172 unregister_randintr(int intr) 173 { 174 struct random_softc *sc = &irandom_ary[intr]; 175 sc->sc_enabled = 0; 176 } 177 178 /* 179 * Dispatch an interrupt. If there's nothing to do we have a stray 180 * interrupt and can just return, leaving the interrupt masked. 181 * 182 * We need to schedule the interrupt and set its irunning[] bit. If 183 * we are not on the interrupt thread's cpu we have to send a message 184 * to the correct cpu that will issue the desired action (interlocking 185 * with the interrupt thread's critical section). 186 * 187 * We are NOT in a critical section, which will allow the scheduled 188 * interrupt to preempt us. The MP lock might *NOT* be held here. 189 */ 190 static void 191 sched_ithd_remote(void *arg) 192 { 193 sched_ithd((int)arg); 194 } 195 196 void 197 sched_ithd(int intr) 198 { 199 thread_t td; 200 201 if ((td = ithreads[intr]) != NULL) { 202 if (intlists[intr] == NULL) { 203 printf("sched_ithd: stray interrupt %d\n", intr); 204 } else { 205 if (td->td_gd == mycpu) { 206 irunning[intr] = 1; 207 lwkt_schedule(td); /* preemption handled internally */ 208 } else { 209 lwkt_send_ipiq(td->td_gd->gd_cpuid, sched_ithd_remote, (void *)intr); 210 } 211 } 212 } else { 213 printf("sched_ithd: stray interrupt %d\n", intr); 214 } 215 } 216 217 /* 218 * Interrupt threads run this as their main loop. The handler should be 219 * in a critical section on entry. 220 */ 221 static void 222 ithread_handler(void *arg) 223 { 224 int intr = (int)arg; 225 intrec_t **list = &intlists[intr]; 226 intrec_t *rec; 227 intrec_t *nrec; 228 struct random_softc *sc = &irandom_ary[intr]; 229 230 KKASSERT(curthread->td_pri >= TDPRI_CRIT); 231 for (;;) { 232 irunning[intr] = 0; 233 for (rec = *list; rec; rec = nrec) { 234 nrec = rec->next; 235 rec->handler(rec->argument); 236 } 237 if (sc->sc_enabled) 238 add_interrupt_randomness(intr); 239 if (irunning[intr] == 0) 240 ithread_done(intr); 241 } 242 } 243 244 /* 245 * Sysctls used by systat and others: hw.intrnames and hw.intrcnt. 246 * The data for this machine dependent, and the declarations are in machine 247 * dependent code. The layout of intrnames and intrcnt however is machine 248 * independent. 249 * 250 * We do not know the length of intrcnt and intrnames at compile time, so 251 * calculate things at run time. 252 */ 253 static int 254 sysctl_intrnames(SYSCTL_HANDLER_ARGS) 255 { 256 return (sysctl_handle_opaque(oidp, intrnames, eintrnames - intrnames, 257 req)); 258 } 259 260 SYSCTL_PROC(_hw, OID_AUTO, intrnames, CTLTYPE_OPAQUE | CTLFLAG_RD, 261 NULL, 0, sysctl_intrnames, "", "Interrupt Names"); 262 263 static int 264 sysctl_intrcnt(SYSCTL_HANDLER_ARGS) 265 { 266 return (sysctl_handle_opaque(oidp, intrcnt, 267 (char *)eintrcnt - (char *)intrcnt, req)); 268 } 269 270 SYSCTL_PROC(_hw, OID_AUTO, intrcnt, CTLTYPE_OPAQUE | CTLFLAG_RD, 271 NULL, 0, sysctl_intrcnt, "", "Interrupt Counts"); 272