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 1.10 2003/07/25 05:26:50 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, "ithread %d", intr); 99 td = ithreads[intr]; 100 if (intr >= NHWI && intr < NHWI + NSWI) 101 lwkt_setpri(td, TDPRI_SOFT_NORM + TDPRI_CRIT * 2); 102 else 103 lwkt_setpri(td, TDPRI_INT_MED + TDPRI_CRIT * 2); 104 } 105 106 /* 107 * Add the record to the interrupt list 108 */ 109 crit_enter(); /* token */ 110 while (*list != NULL) 111 list = &(*list)->next; 112 *list = rec; 113 crit_exit(); 114 return(td); 115 } 116 117 void 118 unregister_swi(int intr, inthand2_t *handler) 119 { 120 if (intr < NHWI || intr >= NHWI + NSWI) 121 panic("register_swi: bad intr %d", intr); 122 unregister_int(intr, handler); 123 } 124 125 void 126 unregister_int(int intr, inthand2_t handler) 127 { 128 intrec_t **list; 129 intrec_t *rec; 130 131 if (intr < 0 || intr > NHWI + NSWI) 132 panic("register_int: bad intr %d", intr); 133 list = &intlists[intr]; 134 crit_enter(); 135 while ((rec = *list) != NULL) { 136 if (rec->handler == (void *)handler) { 137 *list = rec->next; 138 break; 139 } 140 list = &rec->next; 141 } 142 crit_exit(); 143 if (rec != NULL) { 144 free(rec, M_DEVBUF); 145 } else { 146 printf("warning: unregister_int: int %d handler %p not found\n", 147 intr, handler); 148 } 149 } 150 151 void 152 swi_setpriority(int intr, int pri) 153 { 154 struct thread *td; 155 156 if (intr < NHWI || intr >= NHWI + NSWI) 157 panic("register_swi: bad intr %d", intr); 158 if ((td = ithreads[intr]) != NULL) 159 lwkt_setpri(td, pri); 160 } 161 162 void 163 register_randintr(int intr) 164 { 165 struct random_softc *sc = &irandom_ary[intr]; 166 sc->sc_intr = intr; 167 sc->sc_enabled = 1; 168 } 169 170 void 171 unregister_randintr(int intr) 172 { 173 struct random_softc *sc = &irandom_ary[intr]; 174 sc->sc_enabled = 0; 175 } 176 177 /* 178 * Dispatch an interrupt. If there's nothing to do we have a stray 179 * interrupt and can just return, leaving the interrupt masked. 180 * 181 * We need to schedule the interrupt and set its irunning[] bit. If 182 * we are not on the interrupt thread's cpu we have to send a message 183 * to the correct cpu that will issue the desired action (interlocking 184 * with the interrupt thread's critical section). 185 * 186 * We are NOT in a critical section, which will allow the scheduled 187 * interrupt to preempt us. 188 */ 189 static void 190 sched_ithd_remote(void *arg) 191 { 192 sched_ithd((int)arg); 193 } 194 195 void 196 sched_ithd(int intr) 197 { 198 thread_t td; 199 200 if ((td = ithreads[intr]) != NULL) { 201 if (intlists[intr] == NULL) { 202 printf("sched_ithd: stray interrupt %d\n", intr); 203 } else { 204 if (td->td_gd == mycpu) { 205 irunning[intr] = 1; 206 lwkt_schedule(td); /* preemption handled internally */ 207 } else { 208 lwkt_send_ipiq(td->td_gd->gd_cpuid, sched_ithd_remote, (void *)intr); 209 } 210 } 211 } else { 212 printf("sched_ithd: stray interrupt %d\n", intr); 213 } 214 } 215 216 /* 217 * Interrupt threads run this as their main loop. The handler should be 218 * in a critical section on entry. 219 */ 220 static void 221 ithread_handler(void *arg) 222 { 223 int intr = (int)arg; 224 intrec_t **list = &intlists[intr]; 225 intrec_t *rec; 226 intrec_t *nrec; 227 struct random_softc *sc = &irandom_ary[intr]; 228 229 KKASSERT(curthread->td_pri >= TDPRI_CRIT); 230 for (;;) { 231 irunning[intr] = 0; 232 for (rec = *list; rec; rec = nrec) { 233 nrec = rec->next; 234 rec->handler(rec->argument); 235 } 236 if (sc->sc_enabled) 237 add_interrupt_randomness(intr); 238 if (irunning[intr] == 0) 239 ithread_done(intr); 240 } 241 } 242 243 /* 244 * Sysctls used by systat and others: hw.intrnames and hw.intrcnt. 245 * The data for this machine dependent, and the declarations are in machine 246 * dependent code. The layout of intrnames and intrcnt however is machine 247 * independent. 248 * 249 * We do not know the length of intrcnt and intrnames at compile time, so 250 * calculate things at run time. 251 */ 252 static int 253 sysctl_intrnames(SYSCTL_HANDLER_ARGS) 254 { 255 return (sysctl_handle_opaque(oidp, intrnames, eintrnames - intrnames, 256 req)); 257 } 258 259 SYSCTL_PROC(_hw, OID_AUTO, intrnames, CTLTYPE_OPAQUE | CTLFLAG_RD, 260 NULL, 0, sysctl_intrnames, "", "Interrupt Names"); 261 262 static int 263 sysctl_intrcnt(SYSCTL_HANDLER_ARGS) 264 { 265 return (sysctl_handle_opaque(oidp, intrcnt, 266 (char *)eintrcnt - (char *)intrcnt, req)); 267 } 268 269 SYSCTL_PROC(_hw, OID_AUTO, intrcnt, CTLTYPE_OPAQUE | CTLFLAG_RD, 270 NULL, 0, sysctl_intrcnt, "", "Interrupt Counts"); 271