Home | History | Annotate | Line # | Download | only in ofw
ofw_irqhandler.c revision 1.5.10.1
      1 /*	$NetBSD: ofw_irqhandler.c,v 1.5.10.1 2006/05/11 23:26:18 elad 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 1.5.10.1 2006/05/11 23:26:18 elad 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 extern u_int intrcnt[];
     68 
     69 extern u_int soft_interrupts;	/* Only so we can initialise it */
     70 
     71 extern char *_intrnames;
     72 
     73 /* Prototypes */
     74 
     75 int podule_irqhandler		__P((void));
     76 extern void set_spl_masks	__P((void));
     77 
     78 /*
     79  * void irq_init(void)
     80  *
     81  * Initialise the IRQ/FIQ sub system
     82  */
     83 
     84 void
     85 irq_init()
     86 {
     87 	int loop;
     88 
     89 	/* Clear all the IRQ handlers and the irq block masks */
     90 	for (loop = 0; loop < NIRQS; ++loop) {
     91 		irqhandlers[loop] = NULL;
     92 	}
     93 
     94 	/*
     95 	 * Setup the irqmasks for the different Interrupt Priority Levels
     96 	 * We will start with no bits set and these will be updated as handlers
     97 	 * are installed at different IPL's.
     98 	 */
     99 	for (loop = 0; loop < IPL_LEVELS; ++loop)
    100 		irqmasks[loop] = 0;
    101 
    102 	current_intr_depth = 0;
    103 	current_mask = 0x00000000;
    104 	disabled_mask = 0x00000000;
    105 	actual_mask = 0x00000000;
    106 	spl_mask = 0x00000000;
    107 	soft_interrupts = 0x00000000;
    108 
    109 	set_spl_masks();
    110 
    111 	/* Enable IRQ's and FIQ's */
    112 	enable_interrupts(I32_bit | F32_bit);
    113 }
    114 
    115 
    116 /*
    117  * int irq_claim(int irq, irqhandler_t *handler)
    118  *
    119  * Enable an IRQ and install a handler for it.
    120  */
    121 
    122 int
    123 irq_claim(irq, handler)
    124 	int irq;
    125 	irqhandler_t *handler;
    126 {
    127 	int level;
    128 	int loop;
    129 
    130 #ifdef DIAGNOSTIC
    131 	/* Sanity check */
    132 	if (handler == NULL)
    133 		panic("NULL interrupt handler");
    134 	if (handler->ih_func == NULL)
    135 		panic("Interrupt handler does not have a function");
    136 #endif	/* DIAGNOSTIC */
    137 
    138 	/*
    139 	 * IRQ_INSTRUCT indicates that we should get the irq number
    140 	 * from the irq structure
    141 	 */
    142 	if (irq == IRQ_INSTRUCT)
    143 		irq = handler->ih_num;
    144 
    145 	/* Make sure the irq number is valid */
    146 	if (irq < 0 || irq >= NIRQS)
    147 		return(-1);
    148 
    149 	/* Make sure the level is valid */
    150 	if (handler->ih_level < 0 || handler->ih_level >= IPL_LEVELS)
    151     	        return(-1);
    152 
    153 	/* Attach handler at top of chain */
    154 	handler->ih_next = irqhandlers[irq];
    155 	irqhandlers[irq] = handler;
    156 
    157 	/*
    158 	 * Reset the flags for this handler.
    159 	 * As the handler is now in the chain mark it as active.
    160 	 */
    161 	handler->ih_flags = 0 | IRQ_FLAG_ACTIVE;
    162 
    163 	/*
    164 	 * Record the interrupt number for accounting.
    165 	 * Done here as the accounting number may not be the same as the
    166 	 * IRQ number though for the moment they are
    167 	 */
    168 	handler->ih_num = irq;
    169 
    170 #ifdef IRQSTATS
    171 	/* Get the interrupt name from the head of the list */
    172 	if (handler->ih_name) {
    173 		char *ptr = _intrnames + (irq * 14);
    174 		strcpy(ptr, "             ");
    175 		strncpy(ptr, handler->ih_name,
    176 		    min(strlen(handler->ih_name), 13));
    177 	} else {
    178 		char *ptr = _intrnames + (irq * 14);
    179 		sprintf(ptr, "irq %2d     ", irq);
    180 	}
    181 #endif	/* IRQSTATS */
    182 
    183 	/*
    184 	 * Update the irq masks.
    185 	 * Find the lowest interrupt priority on the irq chain.
    186 	 * Interrupt is allowable at priorities lower than this.
    187 	 * If ih_level is out of range then don't bother to update
    188 	 * the masks.
    189 	 */
    190 	if (handler->ih_level >= 0 && handler->ih_level < IPL_LEVELS) {
    191 		irqhandler_t *ptr;
    192 
    193 		/*
    194 		 * Find the lowest interrupt priority on the irq chain.
    195 		 * Interrupt is allowable at priorities lower than this.
    196 		 */
    197 		ptr = irqhandlers[irq];
    198 		if (ptr) {
    199 			level = ptr->ih_level - 1;
    200 			while (ptr) {
    201 				if (ptr->ih_level - 1 < level)
    202 					level = ptr->ih_level - 1;
    203 				ptr = ptr->ih_next;
    204 			}
    205 			while (level >= 0) {
    206 				irqmasks[level] |= (1 << irq);
    207 				--level;
    208 			}
    209 		}
    210 
    211 #include "sl.h"
    212 #include "ppp.h"
    213 #if NSL > 0 || NPPP > 0
    214 		/* In the presence of SLIP or PPP, splimp > spltty. */
    215 		irqmasks[IPL_NET] &= irqmasks[IPL_TTY];
    216 #endif
    217 	}
    218 
    219 	enable_irq(irq);
    220 	set_spl_masks();
    221 
    222 	return(0);
    223 }
    224 
    225 
    226 /*
    227  * int irq_release(int irq, irqhandler_t *handler)
    228  *
    229  * Disable an IRQ and remove a handler for it.
    230  */
    231 
    232 int
    233 irq_release(irq, handler)
    234 	int irq;
    235 	irqhandler_t *handler;
    236 {
    237 	int level;
    238 	int loop;
    239 	irqhandler_t *irqhand;
    240 	irqhandler_t **prehand;
    241 	extern char *_intrnames;
    242 
    243 	/*
    244 	 * IRQ_INSTRUCT indicates that we should get the irq number
    245 	 * from the irq structure
    246 	 */
    247 	if (irq == IRQ_INSTRUCT)
    248 		irq = handler->ih_num;
    249 
    250 	/* Make sure the irq number is valid */
    251 	if (irq < 0 || irq >= NIRQS)
    252 		return(-1);
    253 
    254 	/* Locate the handler */
    255 	irqhand = irqhandlers[irq];
    256 	prehand = &irqhandlers[irq];
    257 
    258 	while (irqhand && handler != irqhand) {
    259 		prehand = &irqhand;
    260 		irqhand = irqhand->ih_next;
    261 	}
    262 
    263 	/* Remove the handler if located */
    264 	if (irqhand)
    265 		*prehand = irqhand->ih_next;
    266 	else
    267 		return(-1);
    268 
    269 	/* Now the handler has been removed from the chain mark is as inactive */
    270 	irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE;
    271 
    272 	/* Make sure the head of the handler list is active */
    273 	if (irqhandlers[irq])
    274 		irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE;
    275 
    276 #ifdef IRQSTATS
    277 	/* Get the interrupt name from the head of the list */
    278 	if (irqhandlers[irq] && irqhandlers[irq]->ih_name) {
    279 		char *ptr = _intrnames + (irq * 14);
    280 		strcpy(ptr, "             ");
    281 		strncpy(ptr, irqhandlers[irq]->ih_name,
    282 		    min(strlen(irqhandlers[irq]->ih_name), 13));
    283 	} else {
    284 		char *ptr = _intrnames + (irq * 14);
    285 		sprintf(ptr, "irq %2d     ", irq);
    286 	}
    287 #endif	/* IRQSTATS */
    288 
    289 	/*
    290 	 * Update the irq masks.
    291 	 * If ih_level is out of range then don't bother to update
    292 	 * the masks.
    293 	 */
    294 	if (handler->ih_level >= 0 && handler->ih_level < IPL_LEVELS) {
    295 		irqhandler_t *ptr;
    296 
    297 		/* Clean the bit from all the masks */
    298 		for (level = 0; level < IPL_LEVELS; ++level)
    299 			irqmasks[level] &= ~(1 << irq);
    300 
    301 		/*
    302 		 * Find the lowest interrupt priority on the irq chain.
    303 		 * Interrupt is allowable at priorities lower than this.
    304 		 */
    305 		ptr = irqhandlers[irq];
    306 		if (ptr) {
    307 			level = ptr->ih_level - 1;
    308 			while (ptr) {
    309 				if (ptr->ih_level - 1 < level)
    310 					level = ptr->ih_level - 1;
    311 				ptr = ptr->ih_next;
    312 			}
    313 			while (level >= 0) {
    314 				irqmasks[level] |= (1 << irq);
    315 				--level;
    316 			}
    317 		}
    318 	}
    319 
    320 	/*
    321 	 * Disable the appropriate mask bit if there are no handlers left for
    322 	 * this IRQ.
    323 	 */
    324 	if (irqhandlers[irq] == NULL)
    325 		disable_irq(irq);
    326 
    327 	set_spl_masks();
    328 
    329 	return(0);
    330 }
    331 
    332 
    333 void *
    334 intr_claim(irq, level, name, ih_func, ih_arg)
    335 	int irq;
    336 	int level;
    337 	const char *name;
    338 	int (*ih_func) __P((void *));
    339 	void *ih_arg;
    340 {
    341 	irqhandler_t *ih;
    342 
    343 	ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT);
    344 	if (!ih)
    345 		panic("intr_claim(): Cannot malloc handler memory");
    346 
    347 	ih->ih_level = level;
    348 	ih->ih_name = name;
    349 	ih->ih_func = ih_func;
    350 	ih->ih_arg = ih_arg;
    351 	ih->ih_flags = 0;
    352 
    353 	if (irq_claim(irq, ih) != 0)
    354 		return(NULL);
    355 	return(ih);
    356 }
    357 
    358 
    359 int
    360 intr_release(arg)
    361 	void *arg;
    362 {
    363 	irqhandler_t *ih = (irqhandler_t *)arg;
    364 
    365 	if (irq_release(ih->ih_num, ih) == 0) {
    366 		free(ih, M_DEVBUF);
    367 		return(0);
    368 	}
    369 	return(1);
    370 }
    371 
    372 
    373 /*
    374  * void disable_irq(int irq)
    375  *
    376  * Disables a specific irq. The irq is removed from the master irq mask
    377  */
    378 
    379 void
    380 disable_irq(irq)
    381 	int irq;
    382 {
    383 	register int oldirqstate;
    384 
    385 	oldirqstate = disable_interrupts(I32_bit);
    386 	current_mask &= ~(1 << irq);
    387 	irq_setmasks();
    388 	restore_interrupts(oldirqstate);
    389 }
    390 
    391 
    392 /*
    393  * void enable_irq(int irq)
    394  *
    395  * Enables a specific irq. The irq is added to the master irq mask
    396  * This routine should be used with caution. A handler should already
    397  * be installed.
    398  */
    399 
    400 void
    401 enable_irq(irq)
    402 	int irq;
    403 {
    404 	register u_int oldirqstate;
    405 
    406 	oldirqstate = disable_interrupts(I32_bit);
    407 	current_mask |= (1 << irq);
    408 	irq_setmasks();
    409 	restore_interrupts(oldirqstate);
    410 }
    411 
    412 
    413 /*
    414  * void stray_irqhandler(u_int mask)
    415  *
    416  * Handler for stray interrupts. This gets called if a handler cannot be
    417  * found for an interrupt.
    418  */
    419 
    420 void	stray_irqhandler(u_int);	/* called from assembly */
    421 
    422 void
    423 stray_irqhandler(mask)
    424 	u_int mask;
    425 {
    426 	static u_int stray_irqs = 0;
    427 
    428 	if (++stray_irqs <= 8)
    429 		log(LOG_ERR, "Stray interrupt %08x%s\n", mask,
    430 		    stray_irqs >= 8 ? ": stopped logging" : "");
    431 }
    432