isa_irqhandler.c revision 1.13
1 /* $NetBSD: isa_irqhandler.c,v 1.13 2007/03/08 20:48:39 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 1.13 2007/03/08 20:48:39 matt Exp $"); 79 80 #include <sys/param.h> 81 #include <sys/systm.h> 82 #include <sys/syslog.h> 83 #include <sys/malloc.h> 84 85 #include <uvm/uvm_extern.h> 86 87 #include <machine/intr.h> 88 #include <machine/irqhandler.h> 89 #include <machine/cpu.h> 90 91 irqhandler_t *irqhandlers[NIRQS]; 92 93 int current_intr_depth; 94 u_int current_mask; 95 u_int actual_mask; 96 u_int disabled_mask; 97 u_int spl_mask; 98 u_int irqmasks[IPL_LEVELS]; 99 100 /* Prototypes */ 101 102 extern void set_spl_masks(void); 103 void irq_calculatemasks(void); 104 void stray_irqhandler(u_int); 105 106 #define WriteWord(a, b) *((volatile unsigned int *)(a)) = (b) 107 108 /* 109 * void irq_init(void) 110 * 111 * Initialise the IRQ/FIQ sub system 112 */ 113 114 void 115 irq_init() 116 { 117 int loop; 118 119 /* Clear all the IRQ handlers and the irq block masks */ 120 for (loop = 0; loop < NIRQS; ++loop) { 121 irqhandlers[loop] = NULL; 122 } 123 124 /* 125 * Setup the irqmasks for the different Interrupt Priority Levels 126 * We will start with no bits set and these will be updated as handlers 127 * are installed at different IPL's. 128 */ 129 for (loop = 0; loop < IPL_LEVELS; ++loop) 130 irqmasks[loop] = 0; 131 132 current_intr_depth = 0; 133 current_mask = 0x00000000; 134 disabled_mask = 0x00000000; 135 actual_mask = 0x00000000; 136 spl_mask = 0x00000000; 137 138 set_spl_masks(); 139 140 /* Enable IRQ's and FIQ's */ 141 enable_interrupts(I32_bit | F32_bit); 142 } 143 144 145 /* 146 * int irq_claim(int irq, irqhandler_t *handler) 147 * 148 * Enable an IRQ and install a handler for it. 149 */ 150 151 int 152 irq_claim(irq, handler, group, name) 153 int irq; 154 irqhandler_t *handler; 155 const char *group; 156 const char *name; 157 { 158 159 #ifdef DIAGNOSTIC 160 /* Sanity check */ 161 if (handler == NULL) 162 panic("NULL interrupt handler"); 163 if (handler->ih_func == NULL) 164 panic("Interrupt handler does not have a function"); 165 #endif /* DIAGNOSTIC */ 166 167 /* 168 * IRQ_INSTRUCT indicates that we should get the irq number 169 * from the irq structure 170 */ 171 if (irq == IRQ_INSTRUCT) 172 irq = handler->ih_num; 173 174 /* Make sure the irq number is valid */ 175 if (irq < 0 || irq >= NIRQS) 176 return(-1); 177 178 /* Make sure the level is valid */ 179 if (handler->ih_level < 0 || handler->ih_level >= IPL_LEVELS) 180 return(-1); 181 182 /* Attach evcnt */ 183 evcnt_attach_dynamic(&handler->ih_ev, EVCNT_TYPE_INTR, NULL, 184 group, name); 185 186 /* Attach handler at top of chain */ 187 handler->ih_next = irqhandlers[irq]; 188 irqhandlers[irq] = handler; 189 190 /* 191 * Reset the flags for this handler. 192 * As the handler is now in the chain mark it as active. 193 */ 194 handler->ih_flags = 0 | IRQ_FLAG_ACTIVE; 195 196 /* 197 * Record the interrupt number for accounting. 198 * Done here as the accounting number may not be the same as the 199 * IRQ number though for the moment they are 200 */ 201 handler->ih_num = irq; 202 203 irq_calculatemasks(); 204 205 enable_irq(irq); 206 set_spl_masks(); 207 return(0); 208 } 209 210 211 /* 212 * int irq_release(int irq, irqhandler_t *handler) 213 * 214 * Disable an IRQ and remove a handler for it. 215 */ 216 217 int 218 irq_release(irq, handler) 219 int irq; 220 irqhandler_t *handler; 221 { 222 irqhandler_t *irqhand; 223 irqhandler_t **prehand; 224 225 /* 226 * IRQ_INSTRUCT indicates that we should get the irq number 227 * from the irq structure 228 */ 229 if (irq == IRQ_INSTRUCT) 230 irq = handler->ih_num; 231 232 /* Make sure the irq number is valid */ 233 if (irq < 0 || irq >= NIRQS) 234 return(-1); 235 236 /* Locate the handler */ 237 prehand = &irqhandlers[irq]; 238 irqhand = *prehand; 239 240 while (irqhand && handler != irqhand) { 241 prehand = &irqhand->ih_next; 242 irqhand = *prehand; 243 } 244 245 /* Remove the handler if located */ 246 if (irqhand) 247 *prehand = irqhand->ih_next; 248 else 249 return(-1); 250 251 /* The handler has been removed from the chain so mark it as inactive */ 252 irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE; 253 254 /* Make sure the head of the handler list is active */ 255 if (irqhandlers[irq]) 256 irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE; 257 258 evcnt_detach(&irqhand->ih_ev); 259 260 irq_calculatemasks(); 261 262 /* 263 * Disable the appropriate mask bit if there are no handlers left for 264 * this IRQ. 265 */ 266 if (irqhandlers[irq] == NULL) 267 disable_irq(irq); 268 269 set_spl_masks(); 270 271 return(0); 272 } 273 274 /* adapted from .../i386/isa/isa_machdep.c */ 275 /* 276 * Recalculate the interrupt masks from scratch. 277 * We could code special registry and deregistry versions of this function that 278 * would be faster, but the code would be nastier, and we don't expect this to 279 * happen very much anyway. 280 */ 281 void 282 irq_calculatemasks() 283 { 284 int irq, level; 285 irqhandler_t *ptr; 286 int irqlevel[NIRQS]; 287 288 /* First, figure out which levels each IRQ uses. */ 289 for (irq = 0; irq < NIRQS; irq++) { 290 int levels = 0; 291 for (ptr = irqhandlers[irq]; ptr; ptr = ptr->ih_next) 292 levels |= 1 << ptr->ih_level; 293 irqlevel[irq] = levels; 294 } 295 296 /* Then figure out which IRQs use each level. */ 297 for (level = 0; level < IPL_LEVELS; level++) { 298 int irqs = 0; 299 for (irq = 0; irq < NIRQS; irq++) 300 if (irqlevel[irq] & (1 << level)) 301 irqs |= 1 << irq; 302 irqmasks[level] = ~irqs; 303 } 304 305 /* 306 * Enforce a hierarchy that gives slow devices a better chance at not 307 * dropping data. 308 */ 309 irqmasks[IPL_NET] &= irqmasks[IPL_BIO]; 310 irqmasks[IPL_TTY] &= irqmasks[IPL_NET]; 311 312 /* 313 * There are tty, network and disk drivers that use free() at interrupt 314 * time, so imp > (tty | net | bio). 315 */ 316 irqmasks[IPL_VM] &= irqmasks[IPL_TTY]; 317 318 irqmasks[IPL_AUDIO] &= irqmasks[IPL_VM]; 319 320 /* 321 * Since run queues may be manipulated by both the statclock and tty, 322 * network, and disk drivers, statclock > (tty | net | bio). 323 */ 324 irqmasks[IPL_CLOCK] &= irqmasks[IPL_AUDIO]; 325 326 /* 327 * IPL_HIGH must block everything that can manipulate a run queue. 328 */ 329 irqmasks[IPL_HIGH] &= irqmasks[IPL_CLOCK]; 330 331 /* 332 * We need serial drivers to run at the absolute highest priority to 333 * avoid overruns, so serial > high. 334 */ 335 irqmasks[IPL_SERIAL] &= irqmasks[IPL_HIGH]; 336 } 337 338 339 void * 340 intr_claim(irq, level, ih_func, ih_arg, group, name) 341 int irq; 342 int level; 343 int (*ih_func)(void *); 344 void *ih_arg; 345 const char *group; 346 const char *name; 347 { 348 irqhandler_t *ih; 349 350 ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT | M_ZERO); 351 if (!ih) 352 panic("intr_claim(): Cannot malloc handler memory"); 353 354 ih->ih_level = level; 355 ih->ih_func = ih_func; 356 ih->ih_arg = ih_arg; 357 ih->ih_flags = 0; 358 359 if (irq_claim(irq, ih, group, name) != 0) 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 free(ih, M_DEVBUF); 373 return(0); 374 } 375 return(1); 376 } 377 378 379 /* 380 * void disable_irq(int irq) 381 * 382 * Disables a specific irq. The irq is removed from the master irq mask 383 */ 384 385 void 386 disable_irq(irq) 387 int irq; 388 { 389 u_int oldirqstate; 390 391 oldirqstate = disable_interrupts(I32_bit); 392 current_mask &= ~(1 << irq); 393 irq_setmasks(); 394 restore_interrupts(oldirqstate); 395 } 396 397 398 /* 399 * void enable_irq(int irq) 400 * 401 * Enables a specific irq. The irq is added to the master irq mask 402 * This routine should be used with caution. A handler should already 403 * be installed. 404 */ 405 406 void 407 enable_irq(irq) 408 int irq; 409 { 410 u_int oldirqstate; 411 412 oldirqstate = disable_interrupts(I32_bit); 413 current_mask |= (1 << irq); 414 irq_setmasks(); 415 restore_interrupts(oldirqstate); 416 } 417 418 419 /* 420 * void stray_irqhandler(u_int mask) 421 * 422 * Handler for stray interrupts. This gets called if a handler cannot be 423 * found for an interrupt. 424 */ 425 426 void 427 stray_irqhandler(mask) 428 u_int mask; 429 { 430 static u_int stray_irqs = 0; 431 432 if (++stray_irqs <= 8) 433 log(LOG_ERR, "Stray interrupt %08x%s\n", mask, 434 stray_irqs >= 8 ? ": stopped logging" : ""); 435 } 436
Indexes created Mon Sep 29 21:09:56 GMT 2025