isa_irqhandler.c revision 1.12
1 /* $NetBSD: isa_irqhandler.c,v 1.12 2007/02/20 01:51:16 matt 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 1.12 2007/02/20 01:51:16 matt 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]; 100 101 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 } 126 127 /* 128 * Setup the irqmasks for the different Interrupt Priority Levels 129 * We will start with no bits set and these will be updated as handlers 130 * are installed at different IPL's. 131 */ 132 for (loop = 0; loop < IPL_LEVELS; ++loop) 133 irqmasks[loop] = 0; 134 135 current_intr_depth = 0; 136 current_mask = 0x00000000; 137 disabled_mask = 0x00000000; 138 actual_mask = 0x00000000; 139 spl_mask = 0x00000000; 140 141 set_spl_masks(); 142 143 /* Enable IRQ's and FIQ's */ 144 enable_interrupts(I32_bit | F32_bit); 145 } 146 147 148 /* 149 * int irq_claim(int irq, irqhandler_t *handler) 150 * 151 * Enable an IRQ and install a handler for it. 152 */ 153 154 int 155 irq_claim(irq, handler) 156 int irq; 157 irqhandler_t *handler; 158 { 159 160 #ifdef DIAGNOSTIC 161 /* Sanity check */ 162 if (handler == NULL) 163 panic("NULL interrupt handler"); 164 if (handler->ih_func == NULL) 165 panic("Interrupt handler does not have a function"); 166 #endif /* DIAGNOSTIC */ 167 168 /* 169 * IRQ_INSTRUCT indicates that we should get the irq number 170 * from the irq structure 171 */ 172 if (irq == IRQ_INSTRUCT) 173 irq = handler->ih_num; 174 175 /* Make sure the irq number is valid */ 176 if (irq < 0 || irq >= NIRQS) 177 return(-1); 178 179 /* Make sure the level is valid */ 180 if (handler->ih_level < 0 || handler->ih_level >= IPL_LEVELS) 181 return(-1); 182 183 /* Attach handler at top of chain */ 184 handler->ih_next = irqhandlers[irq]; 185 irqhandlers[irq] = handler; 186 187 /* 188 * Reset the flags for this handler. 189 * As the handler is now in the chain mark it as active. 190 */ 191 handler->ih_flags = 0 | IRQ_FLAG_ACTIVE; 192 193 /* 194 * Record the interrupt number for accounting. 195 * Done here as the accounting number may not be the same as the 196 * IRQ number though for the moment they are 197 */ 198 handler->ih_num = irq; 199 200 irq_calculatemasks(); 201 202 enable_irq(irq); 203 set_spl_masks(); 204 return(0); 205 } 206 207 208 /* 209 * int irq_release(int irq, irqhandler_t *handler) 210 * 211 * Disable an IRQ and remove a handler for it. 212 */ 213 214 int 215 irq_release(irq, handler) 216 int irq; 217 irqhandler_t *handler; 218 { 219 irqhandler_t *irqhand; 220 irqhandler_t **prehand; 221 222 /* 223 * IRQ_INSTRUCT indicates that we should get the irq number 224 * from the irq structure 225 */ 226 if (irq == IRQ_INSTRUCT) 227 irq = handler->ih_num; 228 229 /* Make sure the irq number is valid */ 230 if (irq < 0 || irq >= NIRQS) 231 return(-1); 232 233 /* Locate the handler */ 234 irqhand = irqhandlers[irq]; 235 prehand = &irqhandlers[irq]; 236 237 while (irqhand && handler != irqhand) { 238 prehand = &irqhand; 239 irqhand = irqhand->ih_next; 240 } 241 242 /* Remove the handler if located */ 243 if (irqhand) 244 *prehand = irqhand->ih_next; 245 else 246 return(-1); 247 248 /* Now the handler has been removed from the chain mark is as inactive */ 249 irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE; 250 251 /* Make sure the head of the handler list is active */ 252 if (irqhandlers[irq]) 253 irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE; 254 255 irq_calculatemasks(); 256 257 /* 258 * Disable the appropriate mask bit if there are no handlers left for 259 * this IRQ. 260 */ 261 if (irqhandlers[irq] == NULL) 262 disable_irq(irq); 263 264 set_spl_masks(); 265 266 return(0); 267 } 268 269 /* adapted from .../i386/isa/isa_machdep.c */ 270 /* 271 * Recalculate the interrupt masks from scratch. 272 * We could code special registry and deregistry versions of this function that 273 * would be faster, but the code would be nastier, and we don't expect this to 274 * happen very much anyway. 275 */ 276 void 277 irq_calculatemasks() 278 { 279 int irq, level; 280 irqhandler_t *ptr; 281 int irqlevel[NIRQS]; 282 283 /* First, figure out which levels each IRQ uses. */ 284 for (irq = 0; irq < NIRQS; irq++) { 285 int levels = 0; 286 for (ptr = irqhandlers[irq]; ptr; ptr = ptr->ih_next) 287 levels |= 1 << ptr->ih_level; 288 irqlevel[irq] = levels; 289 } 290 291 /* Then figure out which IRQs use each level. */ 292 for (level = 0; level < IPL_LEVELS; level++) { 293 int irqs = 0; 294 for (irq = 0; irq < NIRQS; irq++) 295 if (irqlevel[irq] & (1 << level)) 296 irqs |= 1 << irq; 297 irqmasks[level] = ~irqs; 298 } 299 300 /* 301 * Enforce a hierarchy that gives slow devices a better chance at not 302 * dropping data. 303 */ 304 irqmasks[IPL_NET] &= irqmasks[IPL_BIO]; 305 irqmasks[IPL_TTY] &= irqmasks[IPL_NET]; 306 307 /* 308 * There are tty, network and disk drivers that use free() at interrupt 309 * time, so imp > (tty | net | bio). 310 */ 311 irqmasks[IPL_VM] &= irqmasks[IPL_TTY]; 312 313 irqmasks[IPL_AUDIO] &= irqmasks[IPL_VM]; 314 315 /* 316 * Since run queues may be manipulated by both the statclock and tty, 317 * network, and disk drivers, statclock > (tty | net | bio). 318 */ 319 irqmasks[IPL_CLOCK] &= irqmasks[IPL_AUDIO]; 320 321 /* 322 * IPL_HIGH must block everything that can manipulate a run queue. 323 */ 324 irqmasks[IPL_HIGH] &= irqmasks[IPL_CLOCK]; 325 326 /* 327 * We need serial drivers to run at the absolute highest priority to 328 * avoid overruns, so serial > high. 329 */ 330 irqmasks[IPL_SERIAL] &= irqmasks[IPL_HIGH]; 331 } 332 333 334 void * 335 intr_claim(irq, level, name, ih_func, ih_arg) 336 int irq; 337 int level; 338 const char *name; 339 int (*ih_func) __P((void *)); 340 void *ih_arg; 341 { 342 irqhandler_t *ih; 343 344 ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT | M_ZERO); 345 if (!ih) 346 panic("intr_claim(): Cannot malloc handler memory"); 347 348 ih->ih_level = level; 349 ih->ih_func = ih_func; 350 ih->ih_arg = ih_arg; 351 ih->ih_flags = 0; 352 if (name == NULL) { 353 snprintf(ih->ih_evname, sizeof(ih->ih_evname), "irq %2d", irq); 354 name = ih->ih_evname; 355 } 356 evcnt_attach_dynamic(&ih->ih_ev, EVCNT_TYPE_INTR, NULL, NULL, name); 357 358 if (irq_claim(irq, ih) != 0) { 359 evcnt_detach(&ih->ih_ev); 360 return(NULL); 361 } 362 return(ih); 363 } 364 365 int 366 intr_release(arg) 367 void *arg; 368 { 369 irqhandler_t *ih = (irqhandler_t *)arg; 370 371 if (irq_release(ih->ih_num, ih) == 0) { 372 evcnt_detach(&ih->ih_ev); 373 free(ih, M_DEVBUF); 374 return(0); 375 } 376 return(1); 377 } 378 379 380 /* 381 * void disable_irq(int irq) 382 * 383 * Disables a specific irq. The irq is removed from the master irq mask 384 */ 385 386 void 387 disable_irq(irq) 388 int irq; 389 { 390 u_int oldirqstate; 391 392 oldirqstate = disable_interrupts(I32_bit); 393 current_mask &= ~(1 << irq); 394 irq_setmasks(); 395 restore_interrupts(oldirqstate); 396 } 397 398 399 /* 400 * void enable_irq(int irq) 401 * 402 * Enables a specific irq. The irq is added to the master irq mask 403 * This routine should be used with caution. A handler should already 404 * be installed. 405 */ 406 407 void 408 enable_irq(irq) 409 int irq; 410 { 411 u_int oldirqstate; 412 413 oldirqstate = disable_interrupts(I32_bit); 414 current_mask |= (1 << irq); 415 irq_setmasks(); 416 restore_interrupts(oldirqstate); 417 } 418 419 420 /* 421 * void stray_irqhandler(u_int mask) 422 * 423 * Handler for stray interrupts. This gets called if a handler cannot be 424 * found for an interrupt. 425 */ 426 427 void 428 stray_irqhandler(mask) 429 u_int mask; 430 { 431 static u_int stray_irqs = 0; 432 433 if (++stray_irqs <= 8) 434 log(LOG_ERR, "Stray interrupt %08x%s\n", mask, 435 stray_irqs >= 8 ? ": stopped logging" : ""); 436 } 437
Indexes created Mon Sep 29 21:09:56 GMT 2025