1 /* $NetBSD: footbridge_irqhandler.c,v 1.4 2002/01/07 22:58:07 chris Exp $ */ 2 3 /* 4 * Copyright (c) 1994-1998 Mark Brinicombe. 5 * Copyright (c) 1997 Causality Limited 6 * Copyright (c) 1994 Brini. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed by Mark Brinicombe 20 * for the NetBSD Project. 21 * 4. The name of the company nor the name of the author may be used to 22 * endorse or promote products derived from this software without specific 23 * prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 26 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 27 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 28 * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 29 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 30 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 31 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * from: iomd_irqhandler.c,v 1.16 $ 38 */ 39 40 #include "opt_irqstats.h" 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/syslog.h> 45 #include <sys/malloc.h> 46 #include <uvm/uvm_extern.h> 47 48 #include <machine/intr.h> 49 #include <machine/cpu.h> 50 #include <arm/arm32/machdep.h> 51 52 irqhandler_t *irqhandlers[NIRQS]; 53 54 int current_intr_depth; /* Depth of interrupt nesting */ 55 u_int intr_claimed_mask; /* Interrupts that are claimed */ 56 u_int intr_disabled_mask; /* Interrupts that are temporarily disabled */ 57 u_int intr_current_mask; /* Interrupts currently allowable */ 58 u_int spl_mask; 59 u_int irqmasks[IPL_LEVELS]; 60 u_int irqblock[NIRQS]; 61 62 extern u_int soft_interrupts; /* Only so we can initialise it */ 63 64 extern char *_intrnames; 65 66 void stray_irqhandler __P((void)); 67 68 void 69 irq_init(void) 70 { 71 int loop; 72 73 /* Clear all the IRQ handlers and the irq block masks */ 74 for (loop = 0; loop < NIRQS; ++loop) { 75 irqhandlers[loop] = NULL; 76 irqblock[loop] = 0; 77 } 78 79 /* 80 * Setup the irqmasks for the different Interrupt Priority Levels 81 * We will start with no bits set and these will be updated as handlers 82 * are installed at different IPL's. 83 */ 84 for (loop = 0; loop < IPL_LEVELS; ++loop) 85 irqmasks[loop] = 0; 86 87 current_intr_depth = 0; 88 intr_claimed_mask = 0x00000000; 89 intr_disabled_mask = 0x00000000; 90 intr_current_mask = 0x00000000; 91 spl_mask = 0x00000000; 92 soft_interrupts = 0x00000000; 93 94 set_spl_masks(); 95 irq_setmasks(); 96 97 /* Enable IRQ's and FIQ's */ 98 enable_interrupts(I32_bit | F32_bit); 99 } 100 101 void 102 stray_irqhandler() 103 { 104 panic("stray irq\n"); 105 } 106 107 /* 108 * void disable_irq(int irq) 109 * 110 * Disables a specific irq. The irq is removed from the master irq mask 111 * 112 * Use of this function outside this file is deprecated. 113 */ 114 115 void 116 disable_irq(irq) 117 int irq; 118 { 119 int oldirqstate; 120 121 oldirqstate = disable_interrupts(I32_bit); 122 intr_claimed_mask &= ~(1 << irq); 123 intr_current_mask = intr_claimed_mask & ~intr_disabled_mask; 124 irq_setmasks(); 125 restore_interrupts(oldirqstate); 126 } 127 128 129 /* 130 * void enable_irq(int irq) 131 * 132 * Enables a specific irq. The irq is added to the master irq mask 133 * This routine should be used with caution. A handler should already 134 * be installed. 135 * 136 * Use of this function outside this file is deprecated. 137 */ 138 139 void 140 enable_irq(irq) 141 int irq; 142 { 143 u_int oldirqstate; 144 145 oldirqstate = disable_interrupts(I32_bit); 146 intr_claimed_mask |= (1 << irq); 147 intr_current_mask = intr_claimed_mask & ~intr_disabled_mask; 148 irq_setmasks(); 149 restore_interrupts(oldirqstate); 150 } 151 152 /* 153 * int irq_claim(int irq, irqhandler_t *handler) 154 * 155 * Enable an IRQ and install a handler for it. 156 */ 157 158 int 159 irq_claim(irq, handler) 160 int irq; 161 irqhandler_t *handler; 162 { 163 int level; 164 int loop; 165 166 #ifdef DIAGNOSTIC 167 /* Sanity check */ 168 if (handler == NULL) 169 panic("NULL interrupt handler\n"); 170 if (handler->ih_func == NULL) 171 panic("Interrupt handler does not have a function\n"); 172 #endif /* DIAGNOSTIC */ 173 174 /* 175 * IRQ_INSTRUCT indicates that we should get the irq number 176 * from the irq structure 177 */ 178 if (irq == IRQ_INSTRUCT) 179 irq = handler->ih_num; 180 181 /* Make sure the irq number is valid */ 182 if (irq < 0 || irq >= NIRQS) 183 return(-1); 184 185 /* Make sure the level is valid */ 186 if (handler->ih_level < 0 || handler->ih_level >= IPL_LEVELS) 187 return(-1); 188 189 /* Attach handler at top of chain */ 190 handler->ih_next = irqhandlers[irq]; 191 irqhandlers[irq] = handler; 192 193 /* 194 * Reset the flags for this handler. 195 * As the handler is now in the chain mark it as active. 196 */ 197 handler->ih_flags = 0 | IRQ_FLAG_ACTIVE; 198 199 /* 200 * Record the interrupt number for accounting. 201 * Done here as the accounting number may not be the same as the IRQ number 202 * though for the moment they are 203 */ 204 handler->ih_num = irq; 205 206 #ifdef IRQSTATS 207 /* Get the interrupt name from the head of the list */ 208 if (handler->ih_name) { 209 char *ptr = _intrnames + (irq * 14); 210 strcpy(ptr, " "); 211 strncpy(ptr, handler->ih_name, 212 min(strlen(handler->ih_name), 13)); 213 } else { 214 char *ptr = _intrnames + (irq * 14); 215 sprintf(ptr, "irq %2d ", irq); 216 } 217 #endif /* IRQSTATS */ 218 219 /* 220 * Update the irq masks. 221 * If ih_level is out of range then don't bother to update 222 * the masks. 223 */ 224 if (handler->ih_level >= 0 && handler->ih_level < IPL_LEVELS) { 225 irqhandler_t *ptr; 226 227 /* 228 * Find the lowest interrupt priority on the irq chain. 229 * Interrupt is allowable at priorities lower than this. 230 */ 231 ptr = irqhandlers[irq]; 232 if (ptr) { 233 level = ptr->ih_level - 1; 234 while (ptr) { 235 if (ptr->ih_level - 1 < level) 236 level = ptr->ih_level - 1; 237 ptr = ptr->ih_next; 238 } 239 for (loop = 0; loop < IPL_LEVELS; ++loop) { 240 if (level >= loop) 241 irqmasks[loop] |= (1 << irq); 242 else 243 irqmasks[loop] &= ~(1 << irq); 244 } 245 } 246 247 #include "sl.h" 248 #include "ppp.h" 249 #if NSL > 0 || NPPP > 0 250 /* In the presence of SLIP or PPP, splimp > spltty. */ 251 irqmasks[IPL_NET] &= irqmasks[IPL_TTY]; 252 #endif 253 } 254 255 /* 256 * We now need to update the irqblock array. This array indicates 257 * what other interrupts should be blocked when interrupt is asserted 258 * This basically emulates hardware interrupt priorities e.g. by blocking 259 * all other IPL_BIO interrupts with an IPL_BIO interrupt is asserted. 260 * For each interrupt we find the highest IPL and set the block mask to 261 * the interrupt mask for that level. 262 */ 263 for (loop = 0; loop < NIRQS; ++loop) { 264 irqhandler_t *ptr; 265 266 ptr = irqhandlers[loop]; 267 if (ptr) { 268 /* There is at least 1 handler so scan the chain */ 269 level = ptr->ih_level; 270 while (ptr) { 271 if (ptr->ih_level > level) 272 level = ptr->ih_level; 273 ptr = ptr->ih_next; 274 } 275 irqblock[loop] = ~irqmasks[level]; 276 } else 277 /* No handlers for this irq so nothing to block */ 278 irqblock[loop] = 0; 279 } 280 281 enable_irq(irq); 282 set_spl_masks(); 283 284 return(0); 285 } 286 287 288 /* 289 * int irq_release(int irq, irqhandler_t *handler) 290 * 291 * Disable an IRQ and remove a handler for it. 292 */ 293 294 int 295 irq_release(irq, handler) 296 int irq; 297 irqhandler_t *handler; 298 { 299 int level; 300 int loop; 301 irqhandler_t *irqhand; 302 irqhandler_t **prehand; 303 #ifdef IRQSTATS 304 extern char *_intrnames; 305 #endif /* IRQSTATS */ 306 /* 307 * IRQ_INSTRUCT indicates that we should get the irq number 308 * from the irq structure 309 */ 310 if (irq == IRQ_INSTRUCT) 311 irq = handler->ih_num; 312 313 /* Make sure the irq number is valid */ 314 if (irq < 0 || irq >= NIRQS) 315 return(-1); 316 317 /* Locate the handler */ 318 irqhand = irqhandlers[irq]; 319 prehand = &irqhandlers[irq]; 320 321 while (irqhand && handler != irqhand) { 322 prehand = &irqhand->ih_next; 323 irqhand = irqhand->ih_next; 324 } 325 326 /* Remove the handler if located */ 327 if (irqhand) 328 *prehand = irqhand->ih_next; 329 else 330 return(-1); 331 332 /* Now the handler has been removed from the chain mark is as inactive */ 333 irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE; 334 335 /* Make sure the head of the handler list is active */ 336 if (irqhandlers[irq]) 337 irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE; 338 339 #ifdef IRQSTATS 340 /* Get the interrupt name from the head of the list */ 341 if (irqhandlers[irq] && irqhandlers[irq]->ih_name) { 342 char *ptr = _intrnames + (irq * 14); 343 strcpy(ptr, " "); 344 strncpy(ptr, irqhandlers[irq]->ih_name, 345 min(strlen(irqhandlers[irq]->ih_name), 13)); 346 } else { 347 char *ptr = _intrnames + (irq * 14); 348 sprintf(ptr, "irq %2d ", irq); 349 } 350 #endif /* IRQSTATS */ 351 352 /* 353 * Update the irq masks. 354 * If ih_level is out of range then don't bother to update 355 * the masks. 356 */ 357 if (handler->ih_level >= 0 && handler->ih_level < IPL_LEVELS) { 358 irqhandler_t *ptr; 359 360 /* 361 * Find the lowest interrupt priority on the irq chain. 362 * Interrupt is allowable at priorities lower than this. 363 */ 364 ptr = irqhandlers[irq]; 365 if (ptr) { 366 level = ptr->ih_level - 1; 367 while (ptr) { 368 if (ptr->ih_level - 1 < level) 369 level = ptr->ih_level - 1; 370 ptr = ptr->ih_next; 371 } 372 for (loop = 0; loop < IPL_LEVELS; ++loop) { 373 if (level >= loop) 374 irqmasks[loop] |= (1 << irq); 375 else 376 irqmasks[loop] &= ~(1 << irq); 377 } 378 } 379 } 380 381 /* 382 * We now need to update the irqblock array. This array indicates 383 * what other interrupts should be blocked when interrupt is asserted 384 * This basically emulates hardware interrupt priorities e.g. by 385 * blocking all other IPL_BIO interrupts with an IPL_BIO interrupt 386 * is asserted. For each interrupt we find the highest IPL and set 387 * the block mask to the interrupt mask for that level. 388 */ 389 for (loop = 0; loop < NIRQS; ++loop) { 390 irqhandler_t *ptr; 391 392 ptr = irqhandlers[loop]; 393 if (ptr) { 394 /* There is at least 1 handler so scan the chain */ 395 level = ptr->ih_level; 396 while (ptr) { 397 if (ptr->ih_level > level) 398 level = ptr->ih_level; 399 ptr = ptr->ih_next; 400 } 401 irqblock[loop] = ~irqmasks[level]; 402 } else 403 /* No handlers for this irq so nothing to block */ 404 irqblock[loop] = 0; 405 } 406 407 /* 408 * Disable the appropriate mask bit if there are no handlers left for 409 * this IRQ. 410 */ 411 if (irqhandlers[irq] == NULL) 412 disable_irq(irq); 413 414 set_spl_masks(); 415 416 return(0); 417 } 418 419 420 void * 421 intr_claim(irq, level, name, ih_func, ih_arg) 422 int irq; 423 int level; 424 const char *name; 425 int (*ih_func) __P((void *)); 426 void *ih_arg; 427 { 428 irqhandler_t *ih; 429 430 ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT); 431 if (!ih) 432 panic("intr_claim(): Cannot malloc handler memory\n"); 433 434 ih->ih_level = level; 435 ih->ih_name = name; 436 ih->ih_func = ih_func; 437 ih->ih_arg = ih_arg; 438 ih->ih_flags = 0; 439 440 if (irq_claim(irq, ih) != 0) 441 return(NULL); 442 return(ih); 443 } 444 445 446 int 447 intr_release(arg) 448 void *arg; 449 { 450 irqhandler_t *ih = (irqhandler_t *)arg; 451 452 if (irq_release(ih->ih_num, ih) == 0) { 453 free(ih, M_DEVBUF); 454 return(0); 455 } 456 return(1); 457 } 458