1 /* $NetBSD: ofw_irqhandler.c,v 1.4 2004/08/29 17:36:46 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 <sys/cdefs.h> 45 __KERNEL_RCSID(0, "$NetBSD: ofw_irqhandler.c,v 1.4 2004/08/29 17:36:46 thorpej Exp $"); 46 47 #include "opt_irqstats.h" 48 49 #include <sys/param.h> 50 #include <sys/systm.h> 51 #include <sys/syslog.h> 52 #include <sys/malloc.h> 53 54 #include <uvm/uvm_extern.h> 55 56 #include <machine/intr.h> 57 #include <machine/cpu.h> 58 59 irqhandler_t *irqhandlers[NIRQS]; 60 61 int current_intr_depth; 62 u_int current_mask; 63 u_int actual_mask; 64 u_int disabled_mask; 65 u_int spl_mask; 66 u_int irqmasks[IPL_LEVELS]; 67 u_int irqblock[NIRQS]; 68 extern u_int intrcnt[]; 69 70 extern u_int soft_interrupts; /* Only so we can initialise it */ 71 72 extern char *_intrnames; 73 74 /* Prototypes */ 75 76 int podule_irqhandler __P((void)); 77 extern void set_spl_masks __P((void)); 78 79 /* 80 * void irq_init(void) 81 * 82 * Initialise the IRQ/FIQ sub system 83 */ 84 85 void 86 irq_init() 87 { 88 int loop; 89 90 /* Clear all the IRQ handlers and the irq block masks */ 91 for (loop = 0; loop < NIRQS; ++loop) { 92 irqhandlers[loop] = NULL; 93 irqblock[loop] = 0; 94 } 95 96 /* 97 * Setup the irqmasks for the different Interrupt Priority Levels 98 * We will start with no bits set and these will be updated as handlers 99 * are installed at different IPL's. 100 */ 101 for (loop = 0; loop < IPL_LEVELS; ++loop) 102 irqmasks[loop] = 0; 103 104 current_intr_depth = 0; 105 current_mask = 0x00000000; 106 disabled_mask = 0x00000000; 107 actual_mask = 0x00000000; 108 spl_mask = 0x00000000; 109 soft_interrupts = 0x00000000; 110 111 set_spl_masks(); 112 113 /* Enable IRQ's and FIQ's */ 114 enable_interrupts(I32_bit | F32_bit); 115 } 116 117 118 /* 119 * int irq_claim(int irq, irqhandler_t *handler) 120 * 121 * Enable an IRQ and install a handler for it. 122 */ 123 124 int 125 irq_claim(irq, handler) 126 int irq; 127 irqhandler_t *handler; 128 { 129 int level; 130 int loop; 131 132 #ifdef DIAGNOSTIC 133 /* Sanity check */ 134 if (handler == NULL) 135 panic("NULL interrupt handler"); 136 if (handler->ih_func == NULL) 137 panic("Interrupt handler does not have a function"); 138 #endif /* DIAGNOSTIC */ 139 140 /* 141 * IRQ_INSTRUCT indicates that we should get the irq number 142 * from the irq structure 143 */ 144 if (irq == IRQ_INSTRUCT) 145 irq = handler->ih_num; 146 147 /* Make sure the irq number is valid */ 148 if (irq < 0 || irq >= NIRQS) 149 return(-1); 150 151 /* Make sure the level is valid */ 152 if (handler->ih_level < 0 || handler->ih_level >= IPL_LEVELS) 153 return(-1); 154 155 /* Attach handler at top of chain */ 156 handler->ih_next = irqhandlers[irq]; 157 irqhandlers[irq] = handler; 158 159 /* 160 * Reset the flags for this handler. 161 * As the handler is now in the chain mark it as active. 162 */ 163 handler->ih_flags = 0 | IRQ_FLAG_ACTIVE; 164 165 /* 166 * Record the interrupt number for accounting. 167 * Done here as the accounting number may not be the same as the 168 * IRQ number though for the moment they are 169 */ 170 handler->ih_num = irq; 171 172 #ifdef IRQSTATS 173 /* Get the interrupt name from the head of the list */ 174 if (handler->ih_name) { 175 char *ptr = _intrnames + (irq * 14); 176 strcpy(ptr, " "); 177 strncpy(ptr, handler->ih_name, 178 min(strlen(handler->ih_name), 13)); 179 } else { 180 char *ptr = _intrnames + (irq * 14); 181 sprintf(ptr, "irq %2d ", irq); 182 } 183 #endif /* IRQSTATS */ 184 185 /* 186 * Update the irq masks. 187 * Find the lowest interrupt priority on the irq chain. 188 * Interrupt is allowable at priorities lower than this. 189 * If ih_level is out of range then don't bother to update 190 * the masks. 191 */ 192 if (handler->ih_level >= 0 && handler->ih_level < IPL_LEVELS) { 193 irqhandler_t *ptr; 194 195 /* 196 * Find the lowest interrupt priority on the irq chain. 197 * Interrupt is allowable at priorities lower than this. 198 */ 199 ptr = irqhandlers[irq]; 200 if (ptr) { 201 level = ptr->ih_level - 1; 202 while (ptr) { 203 if (ptr->ih_level - 1 < level) 204 level = ptr->ih_level - 1; 205 ptr = ptr->ih_next; 206 } 207 while (level >= 0) { 208 irqmasks[level] |= (1 << irq); 209 --level; 210 } 211 } 212 213 #include "sl.h" 214 #include "ppp.h" 215 #if NSL > 0 || NPPP > 0 216 /* In the presence of SLIP or PPP, splimp > spltty. */ 217 irqmasks[IPL_NET] &= irqmasks[IPL_TTY]; 218 #endif 219 } 220 221 /* 222 * We now need to update the irqblock array. This array indicates 223 * what other interrupts should be blocked when interrupt is asserted 224 * This basically emulates hardware interrupt priorities e.g. by 225 * blocking all other IPL_BIO interrupts with an IPL_BIO interrupt 226 * is asserted. For each interrupt we find the highest IPL and set 227 * the block mask to the interrupt mask for that level. 228 */ 229 230 for (loop = 0; loop < NIRQS; ++loop) { 231 irqhandler_t *ptr; 232 233 ptr = irqhandlers[loop]; 234 if (ptr) { 235 /* There is at least 1 handler so scan the chain */ 236 level = ptr->ih_level; 237 while (ptr) { 238 if (ptr->ih_level > level) 239 level = ptr->ih_level; 240 ptr = ptr->ih_next; 241 } 242 irqblock[loop] = ~irqmasks[level]; 243 } else 244 /* No handlers for this irq so nothing to block */ 245 irqblock[loop] = 0; 246 } 247 248 enable_irq(irq); 249 set_spl_masks(); 250 251 return(0); 252 } 253 254 255 /* 256 * int irq_release(int irq, irqhandler_t *handler) 257 * 258 * Disable an IRQ and remove a handler for it. 259 */ 260 261 int 262 irq_release(irq, handler) 263 int irq; 264 irqhandler_t *handler; 265 { 266 int level; 267 int loop; 268 irqhandler_t *irqhand; 269 irqhandler_t **prehand; 270 extern char *_intrnames; 271 272 /* 273 * IRQ_INSTRUCT indicates that we should get the irq number 274 * from the irq structure 275 */ 276 if (irq == IRQ_INSTRUCT) 277 irq = handler->ih_num; 278 279 /* Make sure the irq number is valid */ 280 if (irq < 0 || irq >= NIRQS) 281 return(-1); 282 283 /* Locate the handler */ 284 irqhand = irqhandlers[irq]; 285 prehand = &irqhandlers[irq]; 286 287 while (irqhand && handler != irqhand) { 288 prehand = &irqhand; 289 irqhand = irqhand->ih_next; 290 } 291 292 /* Remove the handler if located */ 293 if (irqhand) 294 *prehand = irqhand->ih_next; 295 else 296 return(-1); 297 298 /* Now the handler has been removed from the chain mark is as inactive */ 299 irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE; 300 301 /* Make sure the head of the handler list is active */ 302 if (irqhandlers[irq]) 303 irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE; 304 305 #ifdef IRQSTATS 306 /* Get the interrupt name from the head of the list */ 307 if (irqhandlers[irq] && irqhandlers[irq]->ih_name) { 308 char *ptr = _intrnames + (irq * 14); 309 strcpy(ptr, " "); 310 strncpy(ptr, irqhandlers[irq]->ih_name, 311 min(strlen(irqhandlers[irq]->ih_name), 13)); 312 } else { 313 char *ptr = _intrnames + (irq * 14); 314 sprintf(ptr, "irq %2d ", irq); 315 } 316 #endif /* IRQSTATS */ 317 318 /* 319 * Update the irq masks. 320 * If ih_level is out of range then don't bother to update 321 * the masks. 322 */ 323 if (handler->ih_level >= 0 && handler->ih_level < IPL_LEVELS) { 324 irqhandler_t *ptr; 325 326 /* Clean the bit from all the masks */ 327 for (level = 0; level < IPL_LEVELS; ++level) 328 irqmasks[level] &= ~(1 << irq); 329 330 /* 331 * Find the lowest interrupt priority on the irq chain. 332 * Interrupt is allowable at priorities lower than this. 333 */ 334 ptr = irqhandlers[irq]; 335 if (ptr) { 336 level = ptr->ih_level - 1; 337 while (ptr) { 338 if (ptr->ih_level - 1 < level) 339 level = ptr->ih_level - 1; 340 ptr = ptr->ih_next; 341 } 342 while (level >= 0) { 343 irqmasks[level] |= (1 << irq); 344 --level; 345 } 346 } 347 } 348 349 /* 350 * We now need to update the irqblock array. This array indicates 351 * what other interrupts should be blocked when interrupt is asserted 352 * This basically emulates hardware interrupt priorities e.g. by 353 * blocking all other IPL_BIO interrupts with an IPL_BIO interrupt 354 * is asserted. For each interrupt we find the highest IPL and set 355 * the block mask to the interrupt mask for that level. 356 */ 357 for (loop = 0; loop < NIRQS; ++loop) { 358 irqhandler_t *ptr; 359 360 ptr = irqhandlers[loop]; 361 if (ptr) { 362 /* There is at least 1 handler so scan the chain */ 363 level = ptr->ih_level; 364 while (ptr) { 365 if (ptr->ih_level > level) 366 level = ptr->ih_level; 367 ptr = ptr->ih_next; 368 } 369 irqblock[loop] = ~irqmasks[level]; 370 } else 371 /* No handlers for this irq so nothing to block */ 372 irqblock[loop] = 0; 373 } 374 375 /* 376 * Disable the appropriate mask bit if there are no handlers left for 377 * this IRQ. 378 */ 379 if (irqhandlers[irq] == NULL) 380 disable_irq(irq); 381 382 set_spl_masks(); 383 384 return(0); 385 } 386 387 388 void * 389 intr_claim(irq, level, name, ih_func, ih_arg) 390 int irq; 391 int level; 392 const char *name; 393 int (*ih_func) __P((void *)); 394 void *ih_arg; 395 { 396 irqhandler_t *ih; 397 398 ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT); 399 if (!ih) 400 panic("intr_claim(): Cannot malloc handler memory"); 401 402 ih->ih_level = level; 403 ih->ih_name = name; 404 ih->ih_func = ih_func; 405 ih->ih_arg = ih_arg; 406 ih->ih_flags = 0; 407 408 if (irq_claim(irq, ih) != 0) 409 return(NULL); 410 return(ih); 411 } 412 413 414 int 415 intr_release(arg) 416 void *arg; 417 { 418 irqhandler_t *ih = (irqhandler_t *)arg; 419 420 if (irq_release(ih->ih_num, ih) == 0) { 421 free(ih, M_DEVBUF); 422 return(0); 423 } 424 return(1); 425 } 426 427 428 /* 429 * void disable_irq(int irq) 430 * 431 * Disables a specific irq. The irq is removed from the master irq mask 432 */ 433 434 void 435 disable_irq(irq) 436 int irq; 437 { 438 register int oldirqstate; 439 440 oldirqstate = disable_interrupts(I32_bit); 441 current_mask &= ~(1 << irq); 442 irq_setmasks(); 443 restore_interrupts(oldirqstate); 444 } 445 446 447 /* 448 * void enable_irq(int irq) 449 * 450 * Enables a specific irq. The irq is added to the master irq mask 451 * This routine should be used with caution. A handler should already 452 * be installed. 453 */ 454 455 void 456 enable_irq(irq) 457 int irq; 458 { 459 register u_int oldirqstate; 460 461 oldirqstate = disable_interrupts(I32_bit); 462 current_mask |= (1 << irq); 463 irq_setmasks(); 464 restore_interrupts(oldirqstate); 465 } 466 467 468 /* 469 * void stray_irqhandler(u_int mask) 470 * 471 * Handler for stray interrupts. This gets called if a handler cannot be 472 * found for an interrupt. 473 */ 474 475 void stray_irqhandler(u_int); /* called from assembly */ 476 477 void 478 stray_irqhandler(mask) 479 u_int mask; 480 { 481 static u_int stray_irqs = 0; 482 483 if (++stray_irqs <= 8) 484 log(LOG_ERR, "Stray interrupt %08x%s\n", mask, 485 stray_irqs >= 8 ? ": stopped logging" : ""); 486 } 487