isa_irqhandler.c revision 1.6
1 /* $NetBSD: isa_irqhandler.c,v 1.6 2003/07/15 03:36:01 lukem Exp $ */ 2 3 /* 4 * Copyright 1997 5 * Digital Equipment Corporation. All rights reserved. 6 * 7 * This software is furnished under license and may be used and 8 * copied only in accordance with the following terms and conditions. 9 * Subject to these conditions, you may download, copy, install, 10 * use, modify and distribute this software in source and/or binary 11 * form. No title or ownership is transferred hereby. 12 * 13 * 1) Any source code used, modified or distributed must reproduce 14 * and retain this copyright notice and list of conditions as 15 * they appear in the source file. 16 * 17 * 2) No right is granted to use any trade name, trademark, or logo of 18 * Digital Equipment Corporation. Neither the "Digital Equipment 19 * Corporation" name nor any trademark or logo of Digital Equipment 20 * Corporation may be used to endorse or promote products derived 21 * from this software without the prior written permission of 22 * Digital Equipment Corporation. 23 * 24 * 3) This software is provided "AS-IS" and any express or implied 25 * warranties, including but not limited to, any implied warranties 26 * of merchantability, fitness for a particular purpose, or 27 * non-infringement are disclaimed. In no event shall DIGITAL be 28 * liable for any damages whatsoever, and in particular, DIGITAL 29 * shall not be liable for special, indirect, consequential, or 30 * incidental damages or damages for lost profits, loss of 31 * revenue or loss of use, whether such damages arise in contract, 32 * negligence, tort, under statute, in equity, at law or otherwise, 33 * even if advised of the possibility of such damage. 34 */ 35 36 /* 37 * Copyright (c) 1994-1998 Mark Brinicombe. 38 * Copyright (c) 1994 Brini. 39 * All rights reserved. 40 * 41 * This code is derived from software written for Brini by Mark Brinicombe 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. All advertising materials mentioning features or use of this software 52 * must display the following acknowledgement: 53 * This product includes software developed by Mark Brinicombe 54 * for the NetBSD Project. 55 * 4. The name of the company nor the name of the author may be used to 56 * endorse or promote products derived from this software without specific 57 * prior written permission. 58 * 59 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 60 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 61 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 62 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 63 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 64 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 65 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 66 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 67 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 68 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 69 * 70 * IRQ/FIQ initialisation, claim, release and handler routines 71 * 72 * from: irqhandler.c 73 * 74 * Created : 30/09/94 75 */ 76 77 #include <sys/cdefs.h> 78 __KERNEL_RCSID(0, "$NetBSD: isa_irqhandler.c,v 1.6 2003/07/15 03:36:01 lukem Exp $"); 79 80 #include "opt_irqstats.h" 81 82 #include <sys/param.h> 83 #include <sys/systm.h> 84 #include <sys/syslog.h> 85 #include <sys/malloc.h> 86 87 #include <uvm/uvm_extern.h> 88 89 #include <machine/intr.h> 90 #include <machine/cpu.h> 91 92 irqhandler_t *irqhandlers[NIRQS]; 93 94 int current_intr_depth; 95 u_int current_mask; 96 u_int actual_mask; 97 u_int disabled_mask; 98 u_int spl_mask; 99 u_int irqmasks[IPL_LEVELS]; 100 u_int irqblock[NIRQS]; 101 102 extern u_int soft_interrupts; /* Only so we can initialise it */ 103 104 extern char *_intrnames; 105 106 /* Prototypes */ 107 108 extern void set_spl_masks(void); 109 void irq_calculatemasks(void); 110 void stray_irqhandler(u_int); 111 112 #define WriteWord(a, b) *((volatile unsigned int *)(a)) = (b) 113 114 /* 115 * void irq_init(void) 116 * 117 * Initialise the IRQ/FIQ sub system 118 */ 119 120 void 121 irq_init() 122 { 123 int loop; 124 125 /* Clear all the IRQ handlers and the irq block masks */ 126 for (loop = 0; loop < NIRQS; ++loop) { 127 irqhandlers[loop] = NULL; 128 irqblock[loop] = 0; 129 } 130 131 /* 132 * Setup the irqmasks for the different Interrupt Priority Levels 133 * We will start with no bits set and these will be updated as handlers 134 * are installed at different IPL's. 135 */ 136 for (loop = 0; loop < IPL_LEVELS; ++loop) 137 irqmasks[loop] = 0; 138 139 current_intr_depth = 0; 140 current_mask = 0x00000000; 141 disabled_mask = 0x00000000; 142 actual_mask = 0x00000000; 143 spl_mask = 0x00000000; 144 soft_interrupts = 0x00000000; 145 146 set_spl_masks(); 147 148 /* Enable IRQ's and FIQ's */ 149 enable_interrupts(I32_bit | F32_bit); 150 } 151 152 153 /* 154 * int irq_claim(int irq, irqhandler_t *handler) 155 * 156 * Enable an IRQ and install a handler for it. 157 */ 158 159 int 160 irq_claim(irq, handler) 161 int irq; 162 irqhandler_t *handler; 163 { 164 165 #ifdef DIAGNOSTIC 166 /* Sanity check */ 167 if (handler == NULL) 168 panic("NULL interrupt handler"); 169 if (handler->ih_func == NULL) 170 panic("Interrupt handler does not have a function"); 171 #endif /* DIAGNOSTIC */ 172 173 /* 174 * IRQ_INSTRUCT indicates that we should get the irq number 175 * from the irq structure 176 */ 177 if (irq == IRQ_INSTRUCT) 178 irq = handler->ih_num; 179 180 /* Make sure the irq number is valid */ 181 if (irq < 0 || irq >= NIRQS) 182 return(-1); 183 184 /* Make sure the level is valid */ 185 if (handler->ih_level < 0 || handler->ih_level >= IPL_LEVELS) 186 return(-1); 187 188 /* Attach handler at top of chain */ 189 handler->ih_next = irqhandlers[irq]; 190 irqhandlers[irq] = handler; 191 192 /* 193 * Reset the flags for this handler. 194 * As the handler is now in the chain mark it as active. 195 */ 196 handler->ih_flags = 0 | IRQ_FLAG_ACTIVE; 197 198 /* 199 * Record the interrupt number for accounting. 200 * Done here as the accounting number may not be the same as the 201 * IRQ number though for the moment they are 202 */ 203 handler->ih_num = irq; 204 205 #ifdef IRQSTATS 206 /* Get the interrupt name from the head of the list */ 207 if (handler->ih_name) { 208 char *ptr = _intrnames + (irq * 14); 209 strcpy(ptr, " "); 210 strncpy(ptr, handler->ih_name, 211 min(strlen(handler->ih_name), 13)); 212 } else { 213 char *ptr = _intrnames + (irq * 14); 214 sprintf(ptr, "irq %2d ", irq); 215 } 216 #endif /* IRQSTATS */ 217 218 irq_calculatemasks(); 219 220 enable_irq(irq); 221 set_spl_masks(); 222 return(0); 223 } 224 225 226 /* 227 * int irq_release(int irq, irqhandler_t *handler) 228 * 229 * Disable an IRQ and remove a handler for it. 230 */ 231 232 int 233 irq_release(irq, handler) 234 int irq; 235 irqhandler_t *handler; 236 { 237 irqhandler_t *irqhand; 238 irqhandler_t **prehand; 239 #ifdef IRQSTATS 240 extern char *_intrnames; 241 #endif 242 243 /* 244 * IRQ_INSTRUCT indicates that we should get the irq number 245 * from the irq structure 246 */ 247 if (irq == IRQ_INSTRUCT) 248 irq = handler->ih_num; 249 250 /* Make sure the irq number is valid */ 251 if (irq < 0 || irq >= NIRQS) 252 return(-1); 253 254 /* Locate the handler */ 255 irqhand = irqhandlers[irq]; 256 prehand = &irqhandlers[irq]; 257 258 while (irqhand && handler != irqhand) { 259 prehand = &irqhand; 260 irqhand = irqhand->ih_next; 261 } 262 263 /* Remove the handler if located */ 264 if (irqhand) 265 *prehand = irqhand->ih_next; 266 else 267 return(-1); 268 269 /* Now the handler has been removed from the chain mark is as inactive */ 270 irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE; 271 272 /* Make sure the head of the handler list is active */ 273 if (irqhandlers[irq]) 274 irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE; 275 276 #ifdef IRQSTATS 277 /* Get the interrupt name from the head of the list */ 278 if (irqhandlers[irq] && irqhandlers[irq]->ih_name) { 279 char *ptr = _intrnames + (irq * 14); 280 strcpy(ptr, " "); 281 strncpy(ptr, irqhandlers[irq]->ih_name, 282 min(strlen(irqhandlers[irq]->ih_name), 13)); 283 } else { 284 char *ptr = _intrnames + (irq * 14); 285 sprintf(ptr, "irq %2d ", irq); 286 } 287 #endif /* IRQSTATS */ 288 289 irq_calculatemasks(); 290 291 /* 292 * Disable the appropriate mask bit if there are no handlers left for 293 * this IRQ. 294 */ 295 if (irqhandlers[irq] == NULL) 296 disable_irq(irq); 297 298 set_spl_masks(); 299 300 return(0); 301 } 302 303 /* adapted from .../i386/isa/isa_machdep.c */ 304 /* 305 * Recalculate the interrupt masks from scratch. 306 * We could code special registry and deregistry versions of this function that 307 * would be faster, but the code would be nastier, and we don't expect this to 308 * happen very much anyway. 309 */ 310 void 311 irq_calculatemasks() 312 { 313 int irq, level; 314 irqhandler_t *ptr; 315 int irqlevel[NIRQS]; 316 317 /* First, figure out which levels each IRQ uses. */ 318 for (irq = 0; irq < NIRQS; irq++) { 319 int levels = 0; 320 for (ptr = irqhandlers[irq]; ptr; ptr = ptr->ih_next) 321 levels |= 1 << ptr->ih_level; 322 irqlevel[irq] = levels; 323 } 324 325 /* Then figure out which IRQs use each level. */ 326 for (level = 0; level < IPL_LEVELS; level++) { 327 int irqs = 0; 328 for (irq = 0; irq < NIRQS; irq++) 329 if (irqlevel[irq] & (1 << level)) 330 irqs |= 1 << irq; 331 irqmasks[level] = ~irqs; 332 } 333 334 /* 335 * Enforce a hierarchy that gives slow devices a better chance at not 336 * dropping data. 337 */ 338 irqmasks[IPL_NET] &= irqmasks[IPL_BIO]; 339 irqmasks[IPL_TTY] &= irqmasks[IPL_NET]; 340 341 /* 342 * There are tty, network and disk drivers that use free() at interrupt 343 * time, so imp > (tty | net | bio). 344 */ 345 irqmasks[IPL_VM] &= irqmasks[IPL_TTY]; 346 347 irqmasks[IPL_AUDIO] &= irqmasks[IPL_VM]; 348 349 /* 350 * Since run queues may be manipulated by both the statclock and tty, 351 * network, and disk drivers, statclock > (tty | net | bio). 352 */ 353 irqmasks[IPL_CLOCK] &= irqmasks[IPL_AUDIO]; 354 355 /* 356 * IPL_HIGH must block everything that can manipulate a run queue. 357 */ 358 irqmasks[IPL_HIGH] &= irqmasks[IPL_CLOCK]; 359 360 /* 361 * We need serial drivers to run at the absolute highest priority to 362 * avoid overruns, so serial > high. 363 */ 364 irqmasks[IPL_SERIAL] &= irqmasks[IPL_HIGH]; 365 366 /* 367 * We now need to update the irqblock array. This array indicates 368 * what other interrupts should be blocked when interrupt is asserted 369 * This basically emulates hardware interrupt priorities e.g. by 370 * blocking all other IPL_BIO interrupts with an IPL_BIO interrupt 371 * is asserted. For each interrupt we find the highest IPL and set 372 * the block mask to the interrupt mask for that level. 373 */ 374 375 /* And eventually calculate the complete masks. */ 376 for (irq = 0; irq < NIRQS; irq++) { 377 int irqs = 1 << irq; 378 for (ptr = irqhandlers[irq]; ptr; ptr = ptr->ih_next) 379 irqs |= ~(irqmasks[ptr->ih_level]); 380 irqblock[irq] = irqs; 381 } 382 } 383 384 385 void * 386 intr_claim(irq, level, name, ih_func, ih_arg) 387 int irq; 388 int level; 389 const char *name; 390 int (*ih_func) __P((void *)); 391 void *ih_arg; 392 { 393 irqhandler_t *ih; 394 395 ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT); 396 if (!ih) 397 panic("intr_claim(): Cannot malloc handler memory"); 398 399 ih->ih_level = level; 400 ih->ih_name = name; 401 ih->ih_func = ih_func; 402 ih->ih_arg = ih_arg; 403 ih->ih_flags = 0; 404 405 if (irq_claim(irq, ih) != 0) 406 return(NULL); 407 return(ih); 408 } 409 410 int 411 intr_release(arg) 412 void *arg; 413 { 414 irqhandler_t *ih = (irqhandler_t *)arg; 415 416 if (irq_release(ih->ih_num, ih) == 0) { 417 free(ih, M_DEVBUF); 418 return(0); 419 } 420 return(1); 421 } 422 423 424 /* 425 * void disable_irq(int irq) 426 * 427 * Disables a specific irq. The irq is removed from the master irq mask 428 */ 429 430 void 431 disable_irq(irq) 432 int irq; 433 { 434 u_int oldirqstate; 435 436 oldirqstate = disable_interrupts(I32_bit); 437 current_mask &= ~(1 << irq); 438 irq_setmasks(); 439 restore_interrupts(oldirqstate); 440 } 441 442 443 /* 444 * void enable_irq(int irq) 445 * 446 * Enables a specific irq. The irq is added to the master irq mask 447 * This routine should be used with caution. A handler should already 448 * be installed. 449 */ 450 451 void 452 enable_irq(irq) 453 int irq; 454 { 455 u_int oldirqstate; 456 457 oldirqstate = disable_interrupts(I32_bit); 458 current_mask |= (1 << irq); 459 irq_setmasks(); 460 restore_interrupts(oldirqstate); 461 } 462 463 464 /* 465 * void stray_irqhandler(u_int mask) 466 * 467 * Handler for stray interrupts. This gets called if a handler cannot be 468 * found for an interrupt. 469 */ 470 471 void 472 stray_irqhandler(mask) 473 u_int mask; 474 { 475 static u_int stray_irqs = 0; 476 477 if (++stray_irqs <= 8) 478 log(LOG_ERR, "Stray interrupt %08x%s\n", mask, 479 stray_irqs >= 8 ? ": stopped logging" : ""); 480 } 481
Indexes created Mon Sep 29 18:09:42 GMT 2025