1 /* $NetBSD: ofw_irqhandler.c,v 1.1 2002/02/06 21:30:26 thorpej Exp $ */ 2 3 /* 4 * Copyright (c) 1994-1998 Mark Brinicombe. 5 * Copyright (c) 1994 Brini. 6 * All rights reserved. 7 * 8 * This code is derived from software written for Brini by Mark Brinicombe 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by Mark Brinicombe 21 * for the NetBSD Project. 22 * 4. The name of the company nor the name of the author may be used to 23 * endorse or promote products derived from this software without specific 24 * prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 27 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 28 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 29 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 30 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 31 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 35 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 36 * 37 * from: irqhandler.c 38 * 39 * IRQ/FIQ initialisation, claim, release and handler routines 40 * 41 * Created : 30/09/94 42 */ 43 44 #include "opt_irqstats.h" 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/syslog.h> 49 #include <sys/malloc.h> 50 51 #include <uvm/uvm_extern.h> 52 53 #include <machine/intr.h> 54 #include <machine/cpu.h> 55 56 irqhandler_t *irqhandlers[NIRQS]; 57 58 int current_intr_depth; 59 u_int current_mask; 60 u_int actual_mask; 61 u_int disabled_mask; 62 u_int spl_mask; 63 u_int irqmasks[IPL_LEVELS]; 64 u_int irqblock[NIRQS]; 65 extern u_int intrcnt[]; 66 67 extern u_int soft_interrupts; /* Only so we can initialise it */ 68 69 extern char *_intrnames; 70 71 /* Prototypes */ 72 73 int podule_irqhandler __P((void)); 74 extern void set_spl_masks __P((void)); 75 76 /* 77 * void irq_init(void) 78 * 79 * Initialise the IRQ/FIQ sub system 80 */ 81 82 void 83 irq_init() 84 { 85 int loop; 86 87 /* Clear all the IRQ handlers and the irq block masks */ 88 for (loop = 0; loop < NIRQS; ++loop) { 89 irqhandlers[loop] = NULL; 90 irqblock[loop] = 0; 91 } 92 93 /* 94 * Setup the irqmasks for the different Interrupt Priority Levels 95 * We will start with no bits set and these will be updated as handlers 96 * are installed at different IPL's. 97 */ 98 for (loop = 0; loop < IPL_LEVELS; ++loop) 99 irqmasks[loop] = 0; 100 101 current_intr_depth = 0; 102 current_mask = 0x00000000; 103 disabled_mask = 0x00000000; 104 actual_mask = 0x00000000; 105 spl_mask = 0x00000000; 106 soft_interrupts = 0x00000000; 107 108 set_spl_masks(); 109 110 /* Enable IRQ's and FIQ's */ 111 enable_interrupts(I32_bit | F32_bit); 112 } 113 114 115 /* 116 * int irq_claim(int irq, irqhandler_t *handler) 117 * 118 * Enable an IRQ and install a handler for it. 119 */ 120 121 int 122 irq_claim(irq, handler) 123 int irq; 124 irqhandler_t *handler; 125 { 126 int level; 127 int loop; 128 129 #ifdef DIAGNOSTIC 130 /* Sanity check */ 131 if (handler == NULL) 132 panic("NULL interrupt handler\n"); 133 if (handler->ih_func == NULL) 134 panic("Interrupt handler does not have a function\n"); 135 #endif /* DIAGNOSTIC */ 136 137 /* 138 * IRQ_INSTRUCT indicates that we should get the irq number 139 * from the irq structure 140 */ 141 if (irq == IRQ_INSTRUCT) 142 irq = handler->ih_num; 143 144 /* Make sure the irq number is valid */ 145 if (irq < 0 || irq >= NIRQS) 146 return(-1); 147 148 /* Make sure the level is valid */ 149 if (handler->ih_level < 0 || handler->ih_level >= IPL_LEVELS) 150 return(-1); 151 152 /* Attach handler at top of chain */ 153 handler->ih_next = irqhandlers[irq]; 154 irqhandlers[irq] = handler; 155 156 /* 157 * Reset the flags for this handler. 158 * As the handler is now in the chain mark it as active. 159 */ 160 handler->ih_flags = 0 | IRQ_FLAG_ACTIVE; 161 162 /* 163 * Record the interrupt number for accounting. 164 * Done here as the accounting number may not be the same as the 165 * IRQ number though for the moment they are 166 */ 167 handler->ih_num = irq; 168 169 #ifdef IRQSTATS 170 /* Get the interrupt name from the head of the list */ 171 if (handler->ih_name) { 172 char *ptr = _intrnames + (irq * 14); 173 strcpy(ptr, " "); 174 strncpy(ptr, handler->ih_name, 175 min(strlen(handler->ih_name), 13)); 176 } else { 177 char *ptr = _intrnames + (irq * 14); 178 sprintf(ptr, "irq %2d ", irq); 179 } 180 #endif /* IRQSTATS */ 181 182 /* 183 * Update the irq masks. 184 * Find the lowest interrupt priority on the irq chain. 185 * Interrupt is allowable at priorities lower than this. 186 * If ih_level is out of range then don't bother to update 187 * the masks. 188 */ 189 if (handler->ih_level >= 0 && handler->ih_level < IPL_LEVELS) { 190 irqhandler_t *ptr; 191 192 /* 193 * Find the lowest interrupt priority on the irq chain. 194 * Interrupt is allowable at priorities lower than this. 195 */ 196 ptr = irqhandlers[irq]; 197 if (ptr) { 198 level = ptr->ih_level - 1; 199 while (ptr) { 200 if (ptr->ih_level - 1 < level) 201 level = ptr->ih_level - 1; 202 ptr = ptr->ih_next; 203 } 204 while (level >= 0) { 205 irqmasks[level] |= (1 << irq); 206 --level; 207 } 208 } 209 210 #include "sl.h" 211 #include "ppp.h" 212 #if NSL > 0 || NPPP > 0 213 /* In the presence of SLIP or PPP, splimp > spltty. */ 214 irqmasks[IPL_NET] &= irqmasks[IPL_TTY]; 215 #endif 216 } 217 218 /* 219 * We now need to update the irqblock array. This array indicates 220 * what other interrupts should be blocked when interrupt is asserted 221 * This basically emulates hardware interrupt priorities e.g. by 222 * blocking all other IPL_BIO interrupts with an IPL_BIO interrupt 223 * is asserted. For each interrupt we find the highest IPL and set 224 * the block mask to the interrupt mask for that level. 225 */ 226 227 for (loop = 0; loop < NIRQS; ++loop) { 228 irqhandler_t *ptr; 229 230 ptr = irqhandlers[loop]; 231 if (ptr) { 232 /* There is at least 1 handler so scan the chain */ 233 level = ptr->ih_level; 234 while (ptr) { 235 if (ptr->ih_level > level) 236 level = ptr->ih_level; 237 ptr = ptr->ih_next; 238 } 239 irqblock[loop] = ~irqmasks[level]; 240 } else 241 /* No handlers for this irq so nothing to block */ 242 irqblock[loop] = 0; 243 } 244 245 enable_irq(irq); 246 set_spl_masks(); 247 248 return(0); 249 } 250 251 252 /* 253 * int irq_release(int irq, irqhandler_t *handler) 254 * 255 * Disable an IRQ and remove a handler for it. 256 */ 257 258 int 259 irq_release(irq, handler) 260 int irq; 261 irqhandler_t *handler; 262 { 263 int level; 264 int loop; 265 irqhandler_t *irqhand; 266 irqhandler_t **prehand; 267 extern char *_intrnames; 268 269 /* 270 * IRQ_INSTRUCT indicates that we should get the irq number 271 * from the irq structure 272 */ 273 if (irq == IRQ_INSTRUCT) 274 irq = handler->ih_num; 275 276 /* Make sure the irq number is valid */ 277 if (irq < 0 || irq >= NIRQS) 278 return(-1); 279 280 /* Locate the handler */ 281 irqhand = irqhandlers[irq]; 282 prehand = &irqhandlers[irq]; 283 284 while (irqhand && handler != irqhand) { 285 prehand = &irqhand; 286 irqhand = irqhand->ih_next; 287 } 288 289 /* Remove the handler if located */ 290 if (irqhand) 291 *prehand = irqhand->ih_next; 292 else 293 return(-1); 294 295 /* Now the handler has been removed from the chain mark is as inactive */ 296 irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE; 297 298 /* Make sure the head of the handler list is active */ 299 if (irqhandlers[irq]) 300 irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE; 301 302 #ifdef IRQSTATS 303 /* Get the interrupt name from the head of the list */ 304 if (irqhandlers[irq] && irqhandlers[irq]->ih_name) { 305 char *ptr = _intrnames + (irq * 14); 306 strcpy(ptr, " "); 307 strncpy(ptr, irqhandlers[irq]->ih_name, 308 min(strlen(irqhandlers[irq]->ih_name), 13)); 309 } else { 310 char *ptr = _intrnames + (irq * 14); 311 sprintf(ptr, "irq %2d ", irq); 312 } 313 #endif /* IRQSTATS */ 314 315 /* 316 * Update the irq masks. 317 * If ih_level is out of range then don't bother to update 318 * the masks. 319 */ 320 if (handler->ih_level >= 0 && handler->ih_level < IPL_LEVELS) { 321 irqhandler_t *ptr; 322 323 /* Clean the bit from all the masks */ 324 for (level = 0; level < IPL_LEVELS; ++level) 325 irqmasks[level] &= ~(1 << irq); 326 327 /* 328 * Find the lowest interrupt priority on the irq chain. 329 * Interrupt is allowable at priorities lower than this. 330 */ 331 ptr = irqhandlers[irq]; 332 if (ptr) { 333 level = ptr->ih_level - 1; 334 while (ptr) { 335 if (ptr->ih_level - 1 < level) 336 level = ptr->ih_level - 1; 337 ptr = ptr->ih_next; 338 } 339 while (level >= 0) { 340 irqmasks[level] |= (1 << irq); 341 --level; 342 } 343 } 344 } 345 346 /* 347 * We now need to update the irqblock array. This array indicates 348 * what other interrupts should be blocked when interrupt is asserted 349 * This basically emulates hardware interrupt priorities e.g. by 350 * blocking all other IPL_BIO interrupts with an IPL_BIO interrupt 351 * is asserted. For each interrupt we find the highest IPL and set 352 * the block mask to the interrupt mask for that level. 353 */ 354 for (loop = 0; loop < NIRQS; ++loop) { 355 irqhandler_t *ptr; 356 357 ptr = irqhandlers[loop]; 358 if (ptr) { 359 /* There is at least 1 handler so scan the chain */ 360 level = ptr->ih_level; 361 while (ptr) { 362 if (ptr->ih_level > level) 363 level = ptr->ih_level; 364 ptr = ptr->ih_next; 365 } 366 irqblock[loop] = ~irqmasks[level]; 367 } else 368 /* No handlers for this irq so nothing to block */ 369 irqblock[loop] = 0; 370 } 371 372 /* 373 * Disable the appropriate mask bit if there are no handlers left for 374 * this IRQ. 375 */ 376 if (irqhandlers[irq] == NULL) 377 disable_irq(irq); 378 379 set_spl_masks(); 380 381 return(0); 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\n"); 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 } 409 410 411 int 412 intr_release(arg) 413 void *arg; 414 { 415 irqhandler_t *ih = (irqhandler_t *)arg; 416 417 if (irq_release(ih->ih_num, ih) == 0) { 418 free(ih, M_DEVBUF); 419 return(0); 420 } 421 return(1); 422 } 423 424 425 /* 426 * void disable_irq(int irq) 427 * 428 * Disables a specific irq. The irq is removed from the master irq mask 429 */ 430 431 void 432 disable_irq(irq) 433 int irq; 434 { 435 register int oldirqstate; 436 437 oldirqstate = disable_interrupts(I32_bit); 438 current_mask &= ~(1 << irq); 439 irq_setmasks(); 440 restore_interrupts(oldirqstate); 441 } 442 443 444 /* 445 * void enable_irq(int irq) 446 * 447 * Enables a specific irq. The irq is added to the master irq mask 448 * This routine should be used with caution. A handler should already 449 * be installed. 450 */ 451 452 void 453 enable_irq(irq) 454 int irq; 455 { 456 register u_int oldirqstate; 457 458 oldirqstate = disable_interrupts(I32_bit); 459 current_mask |= (1 << irq); 460 irq_setmasks(); 461 restore_interrupts(oldirqstate); 462 } 463 464 465 /* 466 * void stray_irqhandler(u_int mask) 467 * 468 * Handler for stray interrupts. This gets called if a handler cannot be 469 * found for an interrupt. 470 */ 471 472 void 473 stray_irqhandler(mask) 474 u_int mask; 475 { 476 static u_int stray_irqs = 0; 477 478 if (++stray_irqs <= 8) 479 log(LOG_ERR, "Stray interrupt %08x%s\n", mask, 480 stray_irqs >= 8 ? ": stopped logging" : ""); 481 } 482