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ixp425_intr.c revision 1.15.36.3
      1 /*	$NetBSD: ixp425_intr.c,v 1.15.36.3 2008/02/18 21:04:24 mjf Exp $ */
      2 
      3 /*
      4  * Copyright (c) 2003
      5  *	Ichiro FUKUHARA <ichiro (at) ichiro.org>.
      6  * All rights reserved.
      7  *
      8  * Redistribution and use in source and binary forms, with or without
      9  * modification, are permitted provided that the following conditions
     10  * are met:
     11  * 1. Redistributions of source code must retain the above copyright
     12  *    notice, this list of conditions and the following disclaimer.
     13  * 2. Redistributions in binary form must reproduce the above copyright
     14  *    notice, this list of conditions and the following disclaimer in the
     15  *    documentation and/or other materials provided with the distribution.
     16  * 3. All advertising materials mentioning features or use of this software
     17  *    must display the following acknowledgement:
     18  *	This product includes software developed by Ichiro FUKUHARA.
     19  * 4. The name of the company nor the name of the author may be used to
     20  *    endorse or promote products derived from this software without specific
     21  *    prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY ICHIRO FUKUHARA ``AS IS'' AND ANY EXPRESS OR
     24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     26  * IN NO EVENT SHALL ICHIRO FUKUHARA OR THE VOICES IN HIS HEAD BE LIABLE FOR
     27  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  */
     35 /*
     36  * Copyright (c) 2001, 2002 Wasabi Systems, Inc.
     37  * All rights reserved.
     38  *
     39  * Written by Jason R. Thorpe for Wasabi Systems, Inc.
     40  *
     41  * Redistribution and use in source and binary forms, with or without
     42  * modification, are permitted provided that the following conditions
     43  * are met:
     44  * 1. Redistributions of source code must retain the above copyright
     45  *    notice, this list of conditions and the following disclaimer.
     46  * 2. Redistributions in binary form must reproduce the above copyright
     47  *    notice, this list of conditions and the following disclaimer in the
     48  *    documentation and/or other materials provided with the distribution.
     49  * 3. All advertising materials mentioning features or use of this software
     50  *    must display the following acknowledgement:
     51  *      This product includes software developed for the NetBSD Project by
     52  *      Wasabi Systems, Inc.
     53  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
     54  *    or promote products derived from this software without specific prior
     55  *    written permission.
     56  *
     57  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
     58  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     59  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     60  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
     61  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     62  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     63  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     64  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     65  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     66  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     67  * POSSIBILITY OF SUCH DAMAGE.
     68  */
     69 
     70 #include <sys/cdefs.h>
     71 __KERNEL_RCSID(0, "$NetBSD: ixp425_intr.c,v 1.15.36.3 2008/02/18 21:04:24 mjf Exp $");
     72 
     73 #ifndef EVBARM_SPL_NOINLINE
     74 #define	EVBARM_SPL_NOINLINE
     75 #endif
     76 
     77 /*
     78  * Interrupt support for the Intel IXP425 NetworkProcessor.
     79  */
     80 
     81 #include <sys/param.h>
     82 #include <sys/systm.h>
     83 #include <sys/malloc.h>
     84 
     85 #include <uvm/uvm_extern.h>
     86 
     87 #include <machine/bus.h>
     88 #include <machine/intr.h>
     89 
     90 #include <arm/cpufunc.h>
     91 
     92 #include <arm/xscale/ixp425reg.h>
     93 #include <arm/xscale/ixp425var.h>
     94 
     95 /* Interrupt handler queues. */
     96 struct intrq intrq[NIRQ];
     97 
     98 /* Interrupts to mask at each level. */
     99 int ixp425_imask[NIPL];
    100 
    101 /* Current interrupt priority level. */
    102 volatile int current_spl_level;
    103 
    104 /* Interrupts pending. */
    105 volatile int ixp425_ipending;
    106 
    107 /* Software copy of the IRQs we have enabled. */
    108 volatile uint32_t intr_enabled;
    109 
    110 /* Mask if interrupts steered to FIQs. */
    111 uint32_t intr_steer;
    112 
    113 #ifdef __HAVE_FAST_SOFTINTS
    114 /*
    115  * Map a software interrupt queue index
    116  *
    117  * XXX: !NOTE! :XXX
    118  * We 'borrow' bits from the interrupt status register for interrupt sources
    119  * which are not used by the current IXP425 port. Should any of the following
    120  * interrupt sources be used at some future time, this must be revisited.
    121  *
    122  *  Bit#31: SW Interrupt 1
    123  *  Bit#30: SW Interrupt 0
    124  *  Bit#14: Timestamp Timer
    125  *  Bit#11: General-purpose Timer 1
    126  */
    127 static const uint32_t si_to_irqbit[SI_NQUEUES] = {
    128 	IXP425_INT_bit31,		/* SI_SOFT */
    129 	IXP425_INT_bit30,		/* SI_SOFTCLOCK */
    130 	IXP425_INT_bit14,		/* SI_SOFTNET */
    131 	IXP425_INT_bit11,		/* SI_SOFTSERIAL */
    132 };
    133 
    134 #define	SI_TO_IRQBIT(si)	(1U << si_to_irqbit[(si)])
    135 
    136 /*
    137  * Map a software interrupt queue to an interrupt priority level.
    138  */
    139 static const int si_to_ipl[] = {
    140 	[SI_SOFTCLOCK] =	IPL_SOFTCLOCK,
    141 	[SI_SOFTBIO] =		IPL_SOFTBIO,
    142 	[SI_SOFTNET] =		IPL_SOFTNET,
    143 	[SI_SOFTSERIAL] =	IPL_SOFTSERIAL,
    144 };
    145 #endif /* __HAVE_FAST_SOFTINTS */
    146 void	ixp425_intr_dispatch(struct clockframe *frame);
    147 
    148 static inline uint32_t
    149 ixp425_irq_read(void)
    150 {
    151 	return IXPREG(IXP425_INT_STATUS) & intr_enabled;
    152 }
    153 
    154 static inline void
    155 ixp425_set_intrsteer(void)
    156 {
    157 	IXPREG(IXP425_INT_SELECT) = intr_steer & IXP425_INT_HWMASK;
    158 }
    159 
    160 static inline void
    161 ixp425_enable_irq(int irq)
    162 {
    163 
    164 	intr_enabled |= (1U << irq);
    165 	ixp425_set_intrmask();
    166 }
    167 
    168 static inline void
    169 ixp425_disable_irq(int irq)
    170 {
    171 
    172 	intr_enabled &= ~(1U << irq);
    173 	ixp425_set_intrmask();
    174 }
    175 
    176 static inline u_int32_t
    177 ixp425_irq2gpio_bit(int irq)
    178 {
    179 
    180 	static const u_int8_t int2gpio[32] __attribute__ ((aligned(32))) = {
    181 		0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* INT#0 -> INT#5 */
    182 		0x00, 0x01,				/* GPIO#0 -> GPIO#1 */
    183 		0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* INT#8 -> INT#13 */
    184 		0xff, 0xff, 0xff, 0xff, 0xff,		/* INT#14 -> INT#18 */
    185 		0x02, 0x03, 0x04, 0x05, 0x06, 0x07,	/* GPIO#2 -> GPIO#7 */
    186 		0x08, 0x09, 0x0a, 0x0b, 0x0c,		/* GPIO#8 -> GPIO#12 */
    187 		0xff, 0xff				/* INT#30 -> INT#31 */
    188 	};
    189 
    190 #ifdef DEBUG
    191 	if (int2gpio[irq] == 0xff)
    192 		panic("ixp425_irq2gpio_bit: bad GPIO irq: %d\n", irq);
    193 #endif
    194 	return (1U << int2gpio[irq]);
    195 }
    196 
    197 /*
    198  * NOTE: This routine must be called with interrupts disabled in the CPSR.
    199  */
    200 static void
    201 ixp425_intr_calculate_masks(void)
    202 {
    203 	struct intrq *iq;
    204 	struct intrhand *ih;
    205 	int irq, ipl;
    206 
    207 	/* First, figure out which IPLs each IRQ has. */
    208 	for (irq = 0; irq < NIRQ; irq++) {
    209 		int levels = 0;
    210 		iq = &intrq[irq];
    211 		ixp425_disable_irq(irq);
    212 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
    213 		     ih = TAILQ_NEXT(ih, ih_list))
    214 			levels |= (1U << ih->ih_ipl);
    215 		iq->iq_levels = levels;
    216 	}
    217 
    218 	/* Next, figure out which IRQs are used by each IPL. */
    219 	for (ipl = 0; ipl < NIPL; ipl++) {
    220 		int irqs = 0;
    221 		for (irq = 0; irq < NIRQ; irq++) {
    222 			if (intrq[irq].iq_levels & (1U << ipl))
    223 				irqs |= (1U << irq);
    224 		}
    225 		ixp425_imask[ipl] = irqs;
    226 	}
    227 
    228 	KASSERT(ixp425_imask[IPL_NONE] == 0);
    229 
    230 #ifdef __HAVE_FAST_SOFTINTS
    231 	/*
    232 	 * Initialize the soft interrupt masks to block themselves.
    233 	 */
    234 	ixp425_imask[IPL_SOFTCLOCK] = SI_TO_IRQBIT(SI_SOFTCLOCK);
    235 	ixp425_imask[IPL_SOFTBIO] = SI_TO_IRQBIT(SI_SOFTBIO);
    236 	ixp425_imask[IPL_SOFTNET] = SI_TO_IRQBIT(SI_SOFTNET);
    237 	ixp425_imask[IPL_SOFTSERIAL] = SI_TO_IRQBIT(SI_SOFTSERIAL);
    238 #endif
    239 
    240 	/*
    241 	 * Enforce a hierarchy that gives "slow" device (or devices with
    242 	 * limited input buffer space/"real-time" requirements) a better
    243 	 * chance at not dropping data.
    244 	 */
    245 	ixp425_imask[IPL_SOFTBIO] |= ixp425_imask[IPL_SOFTCLOCK];
    246 	ixp425_imask[IPL_SOFTNET] |= ixp425_imask[IPL_SOFTBIO];
    247 	ixp425_imask[IPL_SOFTSERIAL] |= ixp425_imask[IPL_SOFTNET];
    248 	ixp425_imask[IPL_VM] |= ixp425_imask[IPL_SOFTSERIAL];
    249 	ixp425_imask[IPL_SCHED] |= ixp425_imask[IPL_VM];
    250 	ixp425_imask[IPL_HIGH] |= ixp425_imask[IPL_SCHED];
    251 
    252 	/*
    253 	 * Now compute which IRQs must be blocked when servicing any
    254 	 * given IRQ.
    255 	 */
    256 	for (irq = 0; irq < NIRQ; irq++) {
    257 		int irqs = (1U << irq);
    258 		iq = &intrq[irq];
    259 		if (TAILQ_FIRST(&iq->iq_list) != NULL)
    260 			ixp425_enable_irq(irq);
    261 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
    262 		     ih = TAILQ_NEXT(ih, ih_list))
    263 			irqs |= ixp425_imask[ih->ih_ipl];
    264 		iq->iq_mask = irqs;
    265 	}
    266 }
    267 
    268 #ifdef __HAVE_FAST_SOFTINTS
    269 void
    270 ixp425_do_pending(void)
    271 {
    272 	static __cpu_simple_lock_t processing = __SIMPLELOCK_UNLOCKED;
    273 	int new, oldirqstate;
    274 
    275 	if (__cpu_simple_lock_try(&processing) == 0)
    276 		return;
    277 
    278 	new = current_spl_level;
    279 
    280 	oldirqstate = disable_interrupts(I32_bit);
    281 
    282 #define	DO_SOFTINT(si)							\
    283 	if ((ixp425_ipending & ~new) & SI_TO_IRQBIT(si)) {		\
    284 		ixp425_ipending &= ~SI_TO_IRQBIT(si);			\
    285 		current_spl_level |= ixp425_imask[si_to_ipl[(si)]];	\
    286 		restore_interrupts(oldirqstate);			\
    287 		softintr_dispatch(si);					\
    288 		oldirqstate = disable_interrupts(I32_bit);		\
    289 		current_spl_level = new;				\
    290 	}
    291 
    292 	DO_SOFTINT(SI_SOFTSERIAL);
    293 	DO_SOFTINT(SI_SOFTNET);
    294 	DO_SOFTINT(SI_SOFTCLOCK);
    295 	DO_SOFTINT(SI_SOFT);
    296 
    297 	__cpu_simple_unlock(&processing);
    298 
    299 	restore_interrupts(oldirqstate);
    300 }
    301 #endif
    302 
    303 void
    304 splx(int new)
    305 {
    306 
    307 	ixp425_splx(new);
    308 }
    309 
    310 int
    311 _spllower(int ipl)
    312 {
    313 
    314 	return (ixp425_spllower(ipl));
    315 }
    316 
    317 int
    318 _splraise(int ipl)
    319 {
    320 
    321 	return (ixp425_splraise(ipl));
    322 }
    323 
    324 #ifdef __HAVE_FAST_SOFTINTS
    325 void
    326 _setsoftintr(int si)
    327 {
    328 	int oldirqstate;
    329 
    330 	oldirqstate = disable_interrupts(I32_bit);
    331 	ixp425_ipending |= SI_TO_IRQBIT(si);
    332 	restore_interrupts(oldirqstate);
    333 
    334 	/* Process unmasked pending soft interrupts. */
    335 	if ((ixp425_ipending & INT_SWMASK) & ~current_spl_level)
    336 		ixp425_do_pending();
    337 }
    338 #endif /* __HAVE_FAST_SOFTINTS */
    339 
    340 /*
    341  * ixp425_icu_init:
    342  *
    343  * 	Called early in bootstrap to make clear interrupt register
    344  */
    345 void
    346 ixp425_icu_init(void)
    347 {
    348 
    349 	intr_enabled = 0;	/* All interrupts disabled */
    350 	ixp425_set_intrmask();
    351 
    352 	intr_steer = 0;		/* All interrupts steered to IRQ */
    353 	ixp425_set_intrsteer();
    354 }
    355 
    356 /*
    357  * ixp425_intr_init:
    358  *
    359  *	Initialize the rest of the interrupt subsystem, making it
    360  *	ready to handle interrupts from devices.
    361  */
    362 void
    363 ixp425_intr_init(void)
    364 {
    365 	struct intrq *iq;
    366 	int i;
    367 
    368 	intr_enabled = 0;
    369 
    370 	for (i = 0; i < NIRQ; i++) {
    371 		iq = &intrq[i];
    372 		TAILQ_INIT(&iq->iq_list);
    373 
    374 		sprintf(iq->iq_name, "irq %d", i);
    375 		evcnt_attach_dynamic(&iq->iq_ev, EVCNT_TYPE_INTR,
    376 				     NULL, "ixp425", iq->iq_name);
    377 	}
    378 
    379 	ixp425_intr_calculate_masks();
    380 
    381 	/* Enable IRQs (don't yet use FIQs). */
    382 	enable_interrupts(I32_bit);
    383 }
    384 
    385 void *
    386 ixp425_intr_establish(int irq, int ipl, int (*func)(void *), void *arg)
    387 {
    388 	struct intrq *iq;
    389 	struct intrhand *ih;
    390 	u_int oldirqstate;
    391 
    392 	if (irq < 0 || irq > NIRQ)
    393 		panic("ixp425_intr_establish: IRQ %d out of range", irq);
    394 #ifdef DEBUG
    395 	printf("ixp425_intr_establish(irq=%d, ipl=%d, func=%08x, arg=%08x)\n",
    396 	       irq, ipl, (u_int32_t) func, (u_int32_t) arg);
    397 #endif
    398 
    399 	ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT);
    400 	if (ih == NULL)
    401 		return (NULL);
    402 
    403 	ih->ih_func = func;
    404 	ih->ih_arg = arg;
    405 	ih->ih_ipl = ipl;
    406 	ih->ih_irq = irq;
    407 
    408 	iq = &intrq[irq];
    409 
    410 	/* All IXP425 interrupts are level-triggered. */
    411 	iq->iq_ist = IST_LEVEL; /* XXX */
    412 
    413 	oldirqstate = disable_interrupts(I32_bit);
    414 
    415 	TAILQ_INSERT_TAIL(&iq->iq_list, ih, ih_list);
    416 
    417 	ixp425_intr_calculate_masks();
    418 
    419 	restore_interrupts(oldirqstate);
    420 
    421 	return (ih);
    422 }
    423 
    424 void
    425 ixp425_intr_disestablish(void *cookie)
    426 {
    427 	struct intrhand *ih = cookie;
    428 	struct intrq *iq = &intrq[ih->ih_irq];
    429 	int oldirqstate;
    430 
    431 	oldirqstate = disable_interrupts(I32_bit);
    432 
    433 	TAILQ_REMOVE(&iq->iq_list, ih, ih_list);
    434 
    435 	ixp425_intr_calculate_masks();
    436 
    437 	restore_interrupts(oldirqstate);
    438 }
    439 
    440 void
    441 ixp425_intr_dispatch(struct clockframe *frame)
    442 {
    443 	struct intrq *iq;
    444 	struct intrhand *ih;
    445 	int oldirqstate, pcpl, irq, ibit, hwpend;
    446 	struct cpu_info *ci;
    447 
    448 	ci = curcpu();
    449 	ci->ci_idepth++;
    450 	pcpl = current_spl_level;
    451 	hwpend = ixp425_irq_read();
    452 
    453 	/*
    454 	 * Disable all the interrupts that are pending.  We will
    455 	 * reenable them once they are processed and not masked.
    456 	 */
    457 	intr_enabled &= ~hwpend;
    458 	ixp425_set_intrmask();
    459 
    460 	while (hwpend != 0) {
    461 		irq = ffs(hwpend) - 1;
    462 		ibit = (1U << irq);
    463 
    464 		hwpend &= ~ibit;
    465 
    466 		if (pcpl & ibit) {
    467 			/*
    468 			 * IRQ is masked; mark it as pending and check
    469 			 * the next one.  Note: the IRQ is already disabled.
    470 			 */
    471 			ixp425_ipending |= ibit;
    472 			continue;
    473 		}
    474 
    475 		ixp425_ipending &= ~ibit;
    476 
    477 		iq = &intrq[irq];
    478 		iq->iq_ev.ev_count++;
    479 		uvmexp.intrs++;
    480 		current_spl_level |= iq->iq_mask;
    481 
    482 		/* Clear down non-level triggered GPIO interrupts now */
    483 		if ((ibit & IXP425_INT_GPIOMASK) && iq->iq_ist != IST_LEVEL) {
    484 			IXPREG(IXP425_GPIO_VBASE + IXP425_GPIO_GPISR) =
    485 			    ixp425_irq2gpio_bit(irq);
    486 		}
    487 
    488 		oldirqstate = enable_interrupts(I32_bit);
    489 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
    490 		     ih = TAILQ_NEXT(ih, ih_list)) {
    491 			(void) (*ih->ih_func)(ih->ih_arg ? ih->ih_arg : frame);
    492 		}
    493 		restore_interrupts(oldirqstate);
    494 
    495 		/* Clear down level triggered GPIO interrupts now */
    496 		if ((ibit & IXP425_INT_GPIOMASK) && iq->iq_ist == IST_LEVEL) {
    497 			IXPREG(IXP425_GPIO_VBASE + IXP425_GPIO_GPISR) =
    498 			    ixp425_irq2gpio_bit(irq);
    499 		}
    500 
    501 		current_spl_level = pcpl;
    502 
    503 		/* Re-enable this interrupt now that's it's cleared. */
    504 		intr_enabled |= ibit;
    505 		ixp425_set_intrmask();
    506 
    507 		/*
    508 		 * Don't forget to include interrupts which may have
    509 		 * arrived in the meantime.
    510 		 */
    511 		hwpend |= ((ixp425_ipending & IXP425_INT_HWMASK) & ~pcpl);
    512 	}
    513 	ci->ci_idepth--;
    514 
    515 #ifdef __HAVE_FAST_SOFTINTS
    516 	/* Check for pendings soft intrs. */
    517 	if ((ixp425_ipending & INT_SWMASK) & ~current_spl_level) {
    518 		oldirqstate = enable_interrupts(I32_bit);
    519 		ixp425_do_pending();
    520 		restore_interrupts(oldirqstate);
    521 	}
    522 #endif
    523 }
    524