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ixp425_intr.c revision 1.18.10.1
      1 /*	$NetBSD: ixp425_intr.c,v 1.18.10.1 2008/05/16 02:22:04 yamt 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 1.18.10.1 2008/05/16 02:22:04 yamt 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 /* Interrupts pending. */
    102 volatile int ixp425_ipending;
    103 
    104 /* Software copy of the IRQs we have enabled. */
    105 volatile uint32_t intr_enabled;
    106 
    107 /* Mask if interrupts steered to FIQs. */
    108 uint32_t intr_steer;
    109 
    110 #ifdef __HAVE_FAST_SOFTINTS
    111 /*
    112  * Map a software interrupt queue index
    113  *
    114  * XXX: !NOTE! :XXX
    115  * We 'borrow' bits from the interrupt status register for interrupt sources
    116  * which are not used by the current IXP425 port. Should any of the following
    117  * interrupt sources be used at some future time, this must be revisited.
    118  *
    119  *  Bit#31: SW Interrupt 1
    120  *  Bit#30: SW Interrupt 0
    121  *  Bit#14: Timestamp Timer
    122  *  Bit#11: General-purpose Timer 1
    123  */
    124 static const uint32_t si_to_irqbit[SI_NQUEUES] = {
    125 	IXP425_INT_bit31,		/* SI_SOFT */
    126 	IXP425_INT_bit30,		/* SI_SOFTCLOCK */
    127 	IXP425_INT_bit14,		/* SI_SOFTNET */
    128 	IXP425_INT_bit11,		/* SI_SOFTSERIAL */
    129 };
    130 
    131 #define	SI_TO_IRQBIT(si)	(1U << si_to_irqbit[(si)])
    132 
    133 /*
    134  * Map a software interrupt queue to an interrupt priority level.
    135  */
    136 static const int si_to_ipl[] = {
    137 	[SI_SOFTCLOCK] =	IPL_SOFTCLOCK,
    138 	[SI_SOFTBIO] =		IPL_SOFTBIO,
    139 	[SI_SOFTNET] =		IPL_SOFTNET,
    140 	[SI_SOFTSERIAL] =	IPL_SOFTSERIAL,
    141 };
    142 #endif /* __HAVE_FAST_SOFTINTS */
    143 void	ixp425_intr_dispatch(struct clockframe *frame);
    144 
    145 static inline uint32_t
    146 ixp425_irq_read(void)
    147 {
    148 	return IXPREG(IXP425_INT_STATUS) & intr_enabled;
    149 }
    150 
    151 static inline void
    152 ixp425_set_intrsteer(void)
    153 {
    154 	IXPREG(IXP425_INT_SELECT) = intr_steer & IXP425_INT_HWMASK;
    155 }
    156 
    157 static inline void
    158 ixp425_enable_irq(int irq)
    159 {
    160 
    161 	intr_enabled |= (1U << irq);
    162 	ixp425_set_intrmask();
    163 }
    164 
    165 static inline void
    166 ixp425_disable_irq(int irq)
    167 {
    168 
    169 	intr_enabled &= ~(1U << irq);
    170 	ixp425_set_intrmask();
    171 }
    172 
    173 static inline u_int32_t
    174 ixp425_irq2gpio_bit(int irq)
    175 {
    176 
    177 	static const u_int8_t int2gpio[32] __attribute__ ((aligned(32))) = {
    178 		0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* INT#0 -> INT#5 */
    179 		0x00, 0x01,				/* GPIO#0 -> GPIO#1 */
    180 		0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* INT#8 -> INT#13 */
    181 		0xff, 0xff, 0xff, 0xff, 0xff,		/* INT#14 -> INT#18 */
    182 		0x02, 0x03, 0x04, 0x05, 0x06, 0x07,	/* GPIO#2 -> GPIO#7 */
    183 		0x08, 0x09, 0x0a, 0x0b, 0x0c,		/* GPIO#8 -> GPIO#12 */
    184 		0xff, 0xff				/* INT#30 -> INT#31 */
    185 	};
    186 
    187 #ifdef DEBUG
    188 	if (int2gpio[irq] == 0xff)
    189 		panic("ixp425_irq2gpio_bit: bad GPIO irq: %d\n", irq);
    190 #endif
    191 	return (1U << int2gpio[irq]);
    192 }
    193 
    194 /*
    195  * NOTE: This routine must be called with interrupts disabled in the CPSR.
    196  */
    197 static void
    198 ixp425_intr_calculate_masks(void)
    199 {
    200 	struct intrq *iq;
    201 	struct intrhand *ih;
    202 	int irq, ipl;
    203 
    204 	/* First, figure out which IPLs each IRQ has. */
    205 	for (irq = 0; irq < NIRQ; irq++) {
    206 		int levels = 0;
    207 		iq = &intrq[irq];
    208 		ixp425_disable_irq(irq);
    209 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
    210 		     ih = TAILQ_NEXT(ih, ih_list))
    211 			levels |= (1U << ih->ih_ipl);
    212 		iq->iq_levels = levels;
    213 	}
    214 
    215 	/* Next, figure out which IRQs are used by each IPL. */
    216 	for (ipl = 0; ipl < NIPL; ipl++) {
    217 		int irqs = 0;
    218 		for (irq = 0; irq < NIRQ; irq++) {
    219 			if (intrq[irq].iq_levels & (1U << ipl))
    220 				irqs |= (1U << irq);
    221 		}
    222 		ixp425_imask[ipl] = irqs;
    223 	}
    224 
    225 	KASSERT(ixp425_imask[IPL_NONE] == 0);
    226 
    227 #ifdef __HAVE_FAST_SOFTINTS
    228 	/*
    229 	 * Initialize the soft interrupt masks to block themselves.
    230 	 */
    231 	ixp425_imask[IPL_SOFTCLOCK] = SI_TO_IRQBIT(SI_SOFTCLOCK);
    232 	ixp425_imask[IPL_SOFTBIO] = SI_TO_IRQBIT(SI_SOFTBIO);
    233 	ixp425_imask[IPL_SOFTNET] = SI_TO_IRQBIT(SI_SOFTNET);
    234 	ixp425_imask[IPL_SOFTSERIAL] = SI_TO_IRQBIT(SI_SOFTSERIAL);
    235 #endif
    236 
    237 	/*
    238 	 * Enforce a hierarchy that gives "slow" device (or devices with
    239 	 * limited input buffer space/"real-time" requirements) a better
    240 	 * chance at not dropping data.
    241 	 */
    242 	ixp425_imask[IPL_SOFTBIO] |= ixp425_imask[IPL_SOFTCLOCK];
    243 	ixp425_imask[IPL_SOFTNET] |= ixp425_imask[IPL_SOFTBIO];
    244 	ixp425_imask[IPL_SOFTSERIAL] |= ixp425_imask[IPL_SOFTNET];
    245 	ixp425_imask[IPL_VM] |= ixp425_imask[IPL_SOFTSERIAL];
    246 	ixp425_imask[IPL_SCHED] |= ixp425_imask[IPL_VM];
    247 	ixp425_imask[IPL_HIGH] |= ixp425_imask[IPL_SCHED];
    248 
    249 	/*
    250 	 * Now compute which IRQs must be blocked when servicing any
    251 	 * given IRQ.
    252 	 */
    253 	for (irq = 0; irq < NIRQ; irq++) {
    254 		int irqs = (1U << irq);
    255 		iq = &intrq[irq];
    256 		if (TAILQ_FIRST(&iq->iq_list) != NULL)
    257 			ixp425_enable_irq(irq);
    258 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
    259 		     ih = TAILQ_NEXT(ih, ih_list))
    260 			irqs |= ixp425_imask[ih->ih_ipl];
    261 		iq->iq_mask = irqs;
    262 	}
    263 }
    264 
    265 void
    266 splx(int new)
    267 {
    268 	ixp425_splx(new);
    269 }
    270 
    271 int
    272 _spllower(int ipl)
    273 {
    274 	return (ixp425_spllower(ipl));
    275 }
    276 
    277 int
    278 _splraise(int ipl)
    279 {
    280 	return (ixp425_splraise(ipl));
    281 }
    282 
    283 /*
    284  * ixp425_icu_init:
    285  *
    286  * 	Called early in bootstrap to make clear interrupt register
    287  */
    288 void
    289 ixp425_icu_init(void)
    290 {
    291 
    292 	intr_enabled = 0;	/* All interrupts disabled */
    293 	ixp425_set_intrmask();
    294 
    295 	intr_steer = 0;		/* All interrupts steered to IRQ */
    296 	ixp425_set_intrsteer();
    297 }
    298 
    299 /*
    300  * ixp425_intr_init:
    301  *
    302  *	Initialize the rest of the interrupt subsystem, making it
    303  *	ready to handle interrupts from devices.
    304  */
    305 void
    306 ixp425_intr_init(void)
    307 {
    308 	struct intrq *iq;
    309 	int i;
    310 
    311 	intr_enabled = 0;
    312 
    313 	for (i = 0; i < NIRQ; i++) {
    314 		iq = &intrq[i];
    315 		TAILQ_INIT(&iq->iq_list);
    316 
    317 		sprintf(iq->iq_name, "irq %d", i);
    318 		evcnt_attach_dynamic(&iq->iq_ev, EVCNT_TYPE_INTR,
    319 				     NULL, "ixp425", iq->iq_name);
    320 	}
    321 
    322 	ixp425_intr_calculate_masks();
    323 
    324 	/* Enable IRQs (don't yet use FIQs). */
    325 	enable_interrupts(I32_bit);
    326 }
    327 
    328 void *
    329 ixp425_intr_establish(int irq, int ipl, int (*func)(void *), void *arg)
    330 {
    331 	struct intrq *iq;
    332 	struct intrhand *ih;
    333 	u_int oldirqstate;
    334 
    335 	if (irq < 0 || irq > NIRQ)
    336 		panic("ixp425_intr_establish: IRQ %d out of range", irq);
    337 #ifdef DEBUG
    338 	printf("ixp425_intr_establish(irq=%d, ipl=%d, func=%08x, arg=%08x)\n",
    339 	       irq, ipl, (u_int32_t) func, (u_int32_t) arg);
    340 #endif
    341 
    342 	ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT);
    343 	if (ih == NULL)
    344 		return (NULL);
    345 
    346 	ih->ih_func = func;
    347 	ih->ih_arg = arg;
    348 	ih->ih_ipl = ipl;
    349 	ih->ih_irq = irq;
    350 
    351 	iq = &intrq[irq];
    352 
    353 	/* All IXP425 interrupts are level-triggered. */
    354 	iq->iq_ist = IST_LEVEL; /* XXX */
    355 
    356 	oldirqstate = disable_interrupts(I32_bit);
    357 
    358 	TAILQ_INSERT_TAIL(&iq->iq_list, ih, ih_list);
    359 
    360 	ixp425_intr_calculate_masks();
    361 
    362 	restore_interrupts(oldirqstate);
    363 
    364 	return (ih);
    365 }
    366 
    367 void
    368 ixp425_intr_disestablish(void *cookie)
    369 {
    370 	struct intrhand *ih = cookie;
    371 	struct intrq *iq = &intrq[ih->ih_irq];
    372 	int oldirqstate;
    373 
    374 	oldirqstate = disable_interrupts(I32_bit);
    375 
    376 	TAILQ_REMOVE(&iq->iq_list, ih, ih_list);
    377 
    378 	ixp425_intr_calculate_masks();
    379 
    380 	restore_interrupts(oldirqstate);
    381 }
    382 
    383 void
    384 ixp425_intr_dispatch(struct clockframe *frame)
    385 {
    386 	struct intrq *iq;
    387 	struct intrhand *ih;
    388 	int oldirqstate, irq, ibit, hwpend;
    389 	struct cpu_info * const ci = curcpu();
    390 	const int ppl = ci->ci_cpl;
    391 	const uint32_t imask = ixp425_imask[ppl];
    392 
    393 	hwpend = ixp425_irq_read();
    394 
    395 	/*
    396 	 * Disable all the interrupts that are pending.  We will
    397 	 * reenable them once they are processed and not masked.
    398 	 */
    399 	intr_enabled &= ~hwpend;
    400 	ixp425_set_intrmask();
    401 
    402 	while (hwpend != 0) {
    403 		irq = ffs(hwpend) - 1;
    404 		ibit = (1U << irq);
    405 
    406 		hwpend &= ~ibit;
    407 
    408 		if (imask & ibit) {
    409 			/*
    410 			 * IRQ is masked; mark it as pending and check
    411 			 * the next one.  Note: the IRQ is already disabled.
    412 			 */
    413 			ixp425_ipending |= ibit;
    414 			continue;
    415 		}
    416 
    417 		ixp425_ipending &= ~ibit;
    418 
    419 		iq = &intrq[irq];
    420 		iq->iq_ev.ev_count++;
    421 		uvmexp.intrs++;
    422 
    423 		/* Clear down non-level triggered GPIO interrupts now */
    424 		if ((ibit & IXP425_INT_GPIOMASK) && iq->iq_ist != IST_LEVEL) {
    425 			IXPREG(IXP425_GPIO_VBASE + IXP425_GPIO_GPISR) =
    426 			    ixp425_irq2gpio_bit(irq);
    427 		}
    428 
    429 		TAILQ_FOREACH(ih, &iq->iq_list, ih_list) {
    430 			ci->ci_cpl = ih->ih_ipl;
    431 			oldirqstate = enable_interrupts(I32_bit);
    432 			(void) (*ih->ih_func)(ih->ih_arg ? ih->ih_arg : frame);
    433 			restore_interrupts(oldirqstate);
    434 		}
    435 
    436 		/* Clear down level triggered GPIO interrupts now */
    437 		if ((ibit & IXP425_INT_GPIOMASK) && iq->iq_ist == IST_LEVEL) {
    438 			IXPREG(IXP425_GPIO_VBASE + IXP425_GPIO_GPISR) =
    439 			    ixp425_irq2gpio_bit(irq);
    440 		}
    441 
    442 		ci->ci_cpl = ppl;
    443 
    444 		/* Re-enable this interrupt now that's it's cleared. */
    445 		intr_enabled |= ibit;
    446 		ixp425_set_intrmask();
    447 
    448 		/*
    449 		 * Don't forget to include interrupts which may have
    450 		 * arrived in the meantime.
    451 		 */
    452 		hwpend |= ((ixp425_ipending & IXP425_INT_HWMASK) & ~imask);
    453 	}
    454 
    455 #ifdef __HAVE_FAST_SOFTINTS
    456 	cpu_dosoftints();
    457 #endif
    458 }
    459