isa_irqhandler.c revision 1.5
1 /* $NetBSD: isa_irqhandler.c,v 1.5 2003/06/16 20:01:05 thorpej 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 "opt_irqstats.h" 78 79 #include <sys/param.h> 80 #include <sys/systm.h> 81 #include <sys/syslog.h> 82 #include <sys/malloc.h> 83 84 #include <uvm/uvm_extern.h> 85 86 #include <machine/intr.h> 87 #include <machine/cpu.h> 88 89 irqhandler_t *irqhandlers[NIRQS]; 90 91 int current_intr_depth; 92 u_int current_mask; 93 u_int actual_mask; 94 u_int disabled_mask; 95 u_int spl_mask; 96 u_int irqmasks[IPL_LEVELS]; 97 u_int irqblock[NIRQS]; 98 99 extern u_int soft_interrupts; /* Only so we can initialise it */ 100 101 extern char *_intrnames; 102 103 /* Prototypes */ 104 105 extern void set_spl_masks(void); 106 void irq_calculatemasks(void); 107 void stray_irqhandler(u_int); 108 109 #define WriteWord(a, b) *((volatile unsigned int *)(a)) = (b) 110 111 /* 112 * void irq_init(void) 113 * 114 * Initialise the IRQ/FIQ sub system 115 */ 116 117 void 118 irq_init() 119 { 120 int loop; 121 122 /* Clear all the IRQ handlers and the irq block masks */ 123 for (loop = 0; loop < NIRQS; ++loop) { 124 irqhandlers[loop] = NULL; 125 irqblock[loop] = 0; 126 } 127 128 /* 129 * Setup the irqmasks for the different Interrupt Priority Levels 130 * We will start with no bits set and these will be updated as handlers 131 * are installed at different IPL's. 132 */ 133 for (loop = 0; loop < IPL_LEVELS; ++loop) 134 irqmasks[loop] = 0; 135 136 current_intr_depth = 0; 137 current_mask = 0x00000000; 138 disabled_mask = 0x00000000; 139 actual_mask = 0x00000000; 140 spl_mask = 0x00000000; 141 soft_interrupts = 0x00000000; 142 143 set_spl_masks(); 144 145 /* Enable IRQ's and FIQ's */ 146 enable_interrupts(I32_bit | F32_bit); 147 } 148 149 150 /* 151 * int irq_claim(int irq, irqhandler_t *handler) 152 * 153 * Enable an IRQ and install a handler for it. 154 */ 155 156 int 157 irq_claim(irq, handler) 158 int irq; 159 irqhandler_t *handler; 160 { 161 162 #ifdef DIAGNOSTIC 163 /* Sanity check */ 164 if (handler == NULL) 165 panic("NULL interrupt handler"); 166 if (handler->ih_func == NULL) 167 panic("Interrupt handler does not have a function"); 168 #endif /* DIAGNOSTIC */ 169 170 /* 171 * IRQ_INSTRUCT indicates that we should get the irq number 172 * from the irq structure 173 */ 174 if (irq == IRQ_INSTRUCT) 175 irq = handler->ih_num; 176 177 /* Make sure the irq number is valid */ 178 if (irq < 0 || irq >= NIRQS) 179 return(-1); 180 181 /* Make sure the level is valid */ 182 if (handler->ih_level < 0 || handler->ih_level >= IPL_LEVELS) 183 return(-1); 184 185 /* Attach handler at top of chain */ 186 handler->ih_next = irqhandlers[irq]; 187 irqhandlers[irq] = handler; 188 189 /* 190 * Reset the flags for this handler. 191 * As the handler is now in the chain mark it as active. 192 */ 193 handler->ih_flags = 0 | IRQ_FLAG_ACTIVE; 194 195 /* 196 * Record the interrupt number for accounting. 197 * Done here as the accounting number may not be the same as the 198 * IRQ number though for the moment they are 199 */ 200 handler->ih_num = irq; 201 202 #ifdef IRQSTATS 203 /* Get the interrupt name from the head of the list */ 204 if (handler->ih_name) { 205 char *ptr = _intrnames + (irq * 14); 206 strcpy(ptr, " "); 207 strncpy(ptr, handler->ih_name, 208 min(strlen(handler->ih_name), 13)); 209 } else { 210 char *ptr = _intrnames + (irq * 14); 211 sprintf(ptr, "irq %2d ", irq); 212 } 213 #endif /* IRQSTATS */ 214 215 irq_calculatemasks(); 216 217 enable_irq(irq); 218 set_spl_masks(); 219 return(0); 220 } 221 222 223 /* 224 * int irq_release(int irq, irqhandler_t *handler) 225 * 226 * Disable an IRQ and remove a handler for it. 227 */ 228 229 int 230 irq_release(irq, handler) 231 int irq; 232 irqhandler_t *handler; 233 { 234 irqhandler_t *irqhand; 235 irqhandler_t **prehand; 236 #ifdef IRQSTATS 237 extern char *_intrnames; 238 #endif 239 240 /* 241 * IRQ_INSTRUCT indicates that we should get the irq number 242 * from the irq structure 243 */ 244 if (irq == IRQ_INSTRUCT) 245 irq = handler->ih_num; 246 247 /* Make sure the irq number is valid */ 248 if (irq < 0 || irq >= NIRQS) 249 return(-1); 250 251 /* Locate the handler */ 252 irqhand = irqhandlers[irq]; 253 prehand = &irqhandlers[irq]; 254 255 while (irqhand && handler != irqhand) { 256 prehand = &irqhand; 257 irqhand = irqhand->ih_next; 258 } 259 260 /* Remove the handler if located */ 261 if (irqhand) 262 *prehand = irqhand->ih_next; 263 else 264 return(-1); 265 266 /* Now the handler has been removed from the chain mark is as inactive */ 267 irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE; 268 269 /* Make sure the head of the handler list is active */ 270 if (irqhandlers[irq]) 271 irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE; 272 273 #ifdef IRQSTATS 274 /* Get the interrupt name from the head of the list */ 275 if (irqhandlers[irq] && irqhandlers[irq]->ih_name) { 276 char *ptr = _intrnames + (irq * 14); 277 strcpy(ptr, " "); 278 strncpy(ptr, irqhandlers[irq]->ih_name, 279 min(strlen(irqhandlers[irq]->ih_name), 13)); 280 } else { 281 char *ptr = _intrnames + (irq * 14); 282 sprintf(ptr, "irq %2d ", irq); 283 } 284 #endif /* IRQSTATS */ 285 286 irq_calculatemasks(); 287 288 /* 289 * Disable the appropriate mask bit if there are no handlers left for 290 * this IRQ. 291 */ 292 if (irqhandlers[irq] == NULL) 293 disable_irq(irq); 294 295 set_spl_masks(); 296 297 return(0); 298 } 299 300 /* adapted from .../i386/isa/isa_machdep.c */ 301 /* 302 * Recalculate the interrupt masks from scratch. 303 * We could code special registry and deregistry versions of this function that 304 * would be faster, but the code would be nastier, and we don't expect this to 305 * happen very much anyway. 306 */ 307 void 308 irq_calculatemasks() 309 { 310 int irq, level; 311 irqhandler_t *ptr; 312 int irqlevel[NIRQS]; 313 314 /* First, figure out which levels each IRQ uses. */ 315 for (irq = 0; irq < NIRQS; irq++) { 316 int levels = 0; 317 for (ptr = irqhandlers[irq]; ptr; ptr = ptr->ih_next) 318 levels |= 1 << ptr->ih_level; 319 irqlevel[irq] = levels; 320 } 321 322 /* Then figure out which IRQs use each level. */ 323 for (level = 0; level < IPL_LEVELS; level++) { 324 int irqs = 0; 325 for (irq = 0; irq < NIRQS; irq++) 326 if (irqlevel[irq] & (1 << level)) 327 irqs |= 1 << irq; 328 irqmasks[level] = ~irqs; 329 } 330 331 /* 332 * Enforce a hierarchy that gives slow devices a better chance at not 333 * dropping data. 334 */ 335 irqmasks[IPL_NET] &= irqmasks[IPL_BIO]; 336 irqmasks[IPL_TTY] &= irqmasks[IPL_NET]; 337 338 /* 339 * There are tty, network and disk drivers that use free() at interrupt 340 * time, so imp > (tty | net | bio). 341 */ 342 irqmasks[IPL_VM] &= irqmasks[IPL_TTY]; 343 344 irqmasks[IPL_AUDIO] &= irqmasks[IPL_VM]; 345 346 /* 347 * Since run queues may be manipulated by both the statclock and tty, 348 * network, and disk drivers, statclock > (tty | net | bio). 349 */ 350 irqmasks[IPL_CLOCK] &= irqmasks[IPL_AUDIO]; 351 352 /* 353 * IPL_HIGH must block everything that can manipulate a run queue. 354 */ 355 irqmasks[IPL_HIGH] &= irqmasks[IPL_CLOCK]; 356 357 /* 358 * We need serial drivers to run at the absolute highest priority to 359 * avoid overruns, so serial > high. 360 */ 361 irqmasks[IPL_SERIAL] &= irqmasks[IPL_HIGH]; 362 363 /* 364 * We now need to update the irqblock array. This array indicates 365 * what other interrupts should be blocked when interrupt is asserted 366 * This basically emulates hardware interrupt priorities e.g. by 367 * blocking all other IPL_BIO interrupts with an IPL_BIO interrupt 368 * is asserted. For each interrupt we find the highest IPL and set 369 * the block mask to the interrupt mask for that level. 370 */ 371 372 /* And eventually calculate the complete masks. */ 373 for (irq = 0; irq < NIRQS; irq++) { 374 int irqs = 1 << irq; 375 for (ptr = irqhandlers[irq]; ptr; ptr = ptr->ih_next) 376 irqs |= ~(irqmasks[ptr->ih_level]); 377 irqblock[irq] = irqs; 378 } 379 } 380 381 382 void * 383 intr_claim(irq, level, name, ih_func, ih_arg) 384 int irq; 385 int level; 386 const char *name; 387 int (*ih_func) __P((void *)); 388 void *ih_arg; 389 { 390 irqhandler_t *ih; 391 392 ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT); 393 if (!ih) 394 panic("intr_claim(): Cannot malloc handler memory"); 395 396 ih->ih_level = level; 397 ih->ih_name = name; 398 ih->ih_func = ih_func; 399 ih->ih_arg = ih_arg; 400 ih->ih_flags = 0; 401 402 if (irq_claim(irq, ih) != 0) 403 return(NULL); 404 return(ih); 405 } 406 407 int 408 intr_release(arg) 409 void *arg; 410 { 411 irqhandler_t *ih = (irqhandler_t *)arg; 412 413 if (irq_release(ih->ih_num, ih) == 0) { 414 free(ih, M_DEVBUF); 415 return(0); 416 } 417 return(1); 418 } 419 420 421 /* 422 * void disable_irq(int irq) 423 * 424 * Disables a specific irq. The irq is removed from the master irq mask 425 */ 426 427 void 428 disable_irq(irq) 429 int irq; 430 { 431 u_int oldirqstate; 432 433 oldirqstate = disable_interrupts(I32_bit); 434 current_mask &= ~(1 << irq); 435 irq_setmasks(); 436 restore_interrupts(oldirqstate); 437 } 438 439 440 /* 441 * void enable_irq(int irq) 442 * 443 * Enables a specific irq. The irq is added to the master irq mask 444 * This routine should be used with caution. A handler should already 445 * be installed. 446 */ 447 448 void 449 enable_irq(irq) 450 int irq; 451 { 452 u_int oldirqstate; 453 454 oldirqstate = disable_interrupts(I32_bit); 455 current_mask |= (1 << irq); 456 irq_setmasks(); 457 restore_interrupts(oldirqstate); 458 } 459 460 461 /* 462 * void stray_irqhandler(u_int mask) 463 * 464 * Handler for stray interrupts. This gets called if a handler cannot be 465 * found for an interrupt. 466 */ 467 468 void 469 stray_irqhandler(mask) 470 u_int mask; 471 { 472 static u_int stray_irqs = 0; 473 474 if (++stray_irqs <= 8) 475 log(LOG_ERR, "Stray interrupt %08x%s\n", mask, 476 stray_irqs >= 8 ? ": stopped logging" : ""); 477 } 478
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