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pci_550.c revision 1.5
      1  1.5  thorpej /* $NetBSD: pci_550.c,v 1.5 1998/06/05 19:04:51 thorpej Exp $ */
      2  1.1  thorpej 
      3  1.1  thorpej /*-
      4  1.1  thorpej  * Copyright (c) 1998 The NetBSD Foundation, Inc.
      5  1.1  thorpej  * All rights reserved.
      6  1.1  thorpej  *
      7  1.1  thorpej  * This code is derived from software contributed to The NetBSD Foundation
      8  1.3     ross  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
      9  1.4  thorpej  * NASA Ames Research Center, and by Andrew Gallatin.
     10  1.1  thorpej  *
     11  1.1  thorpej  * Redistribution and use in source and binary forms, with or without
     12  1.1  thorpej  * modification, are permitted provided that the following conditions
     13  1.1  thorpej  * are met:
     14  1.1  thorpej  * 1. Redistributions of source code must retain the above copyright
     15  1.1  thorpej  *    notice, this list of conditions and the following disclaimer.
     16  1.1  thorpej  * 2. Redistributions in binary form must reproduce the above copyright
     17  1.1  thorpej  *    notice, this list of conditions and the following disclaimer in the
     18  1.1  thorpej  *    documentation and/or other materials provided with the distribution.
     19  1.1  thorpej  * 3. All advertising materials mentioning features or use of this software
     20  1.1  thorpej  *    must display the following acknowledgement:
     21  1.1  thorpej  *	This product includes software developed by the NetBSD
     22  1.1  thorpej  *	Foundation, Inc. and its contributors.
     23  1.1  thorpej  * 4. Neither the name of The NetBSD Foundation nor the names of its
     24  1.1  thorpej  *    contributors may be used to endorse or promote products derived
     25  1.1  thorpej  *    from this software without specific prior written permission.
     26  1.1  thorpej  *
     27  1.1  thorpej  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     28  1.1  thorpej  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     29  1.1  thorpej  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     30  1.1  thorpej  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     31  1.1  thorpej  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     32  1.1  thorpej  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     33  1.1  thorpej  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     34  1.1  thorpej  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     35  1.1  thorpej  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     36  1.1  thorpej  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     37  1.1  thorpej  * POSSIBILITY OF SUCH DAMAGE.
     38  1.1  thorpej  */
     39  1.1  thorpej 
     40  1.1  thorpej /*
     41  1.1  thorpej  * Copyright (c) 1995, 1996 Carnegie-Mellon University.
     42  1.1  thorpej  * All rights reserved.
     43  1.1  thorpej  *
     44  1.1  thorpej  * Author: Chris G. Demetriou
     45  1.1  thorpej  *
     46  1.1  thorpej  * Permission to use, copy, modify and distribute this software and
     47  1.1  thorpej  * its documentation is hereby granted, provided that both the copyright
     48  1.1  thorpej  * notice and this permission notice appear in all copies of the
     49  1.1  thorpej  * software, derivative works or modified versions, and any portions
     50  1.1  thorpej  * thereof, and that both notices appear in supporting documentation.
     51  1.1  thorpej  *
     52  1.1  thorpej  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
     53  1.1  thorpej  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
     54  1.1  thorpej  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
     55  1.1  thorpej  *
     56  1.1  thorpej  * Carnegie Mellon requests users of this software to return to
     57  1.1  thorpej  *
     58  1.1  thorpej  *  Software Distribution Coordinator  or  Software.Distribution (at) CS.CMU.EDU
     59  1.1  thorpej  *  School of Computer Science
     60  1.1  thorpej  *  Carnegie Mellon University
     61  1.1  thorpej  *  Pittsburgh PA 15213-3890
     62  1.1  thorpej  *
     63  1.1  thorpej  * any improvements or extensions that they make and grant Carnegie the
     64  1.1  thorpej  * rights to redistribute these changes.
     65  1.1  thorpej  */
     66  1.1  thorpej 
     67  1.1  thorpej #include <sys/cdefs.h>			/* RCS ID & Copyright macro defns */
     68  1.1  thorpej 
     69  1.5  thorpej __KERNEL_RCSID(0, "$NetBSD: pci_550.c,v 1.5 1998/06/05 19:04:51 thorpej Exp $");
     70  1.1  thorpej 
     71  1.1  thorpej #include <sys/types.h>
     72  1.1  thorpej #include <sys/param.h>
     73  1.1  thorpej #include <sys/time.h>
     74  1.1  thorpej #include <sys/systm.h>
     75  1.1  thorpej #include <sys/errno.h>
     76  1.1  thorpej #include <sys/malloc.h>
     77  1.1  thorpej #include <sys/device.h>
     78  1.1  thorpej #include <sys/syslog.h>
     79  1.1  thorpej 
     80  1.1  thorpej #include <vm/vm.h>
     81  1.1  thorpej 
     82  1.1  thorpej #include <machine/autoconf.h>
     83  1.5  thorpej #include <machine/rpb.h>
     84  1.1  thorpej 
     85  1.1  thorpej #include <dev/pci/pcireg.h>
     86  1.1  thorpej #include <dev/pci/pcivar.h>
     87  1.1  thorpej #include <dev/pci/pciidereg.h>
     88  1.1  thorpej #include <dev/pci/pciidevar.h>
     89  1.1  thorpej 
     90  1.1  thorpej #include <alpha/pci/ciareg.h>
     91  1.1  thorpej #include <alpha/pci/ciavar.h>
     92  1.1  thorpej 
     93  1.1  thorpej #include <alpha/pci/pci_550.h>
     94  1.1  thorpej 
     95  1.1  thorpej #ifndef EVCNT_COUNTERS
     96  1.1  thorpej #include <machine/intrcnt.h>
     97  1.1  thorpej #endif
     98  1.1  thorpej 
     99  1.1  thorpej #include "sio.h"
    100  1.1  thorpej #if NSIO
    101  1.1  thorpej #include <alpha/pci/siovar.h>
    102  1.1  thorpej #endif
    103  1.1  thorpej 
    104  1.1  thorpej int	dec_550_intr_map __P((void *, pcitag_t, int, int,
    105  1.1  thorpej 	    pci_intr_handle_t *));
    106  1.1  thorpej const char *dec_550_intr_string __P((void *, pci_intr_handle_t));
    107  1.1  thorpej void	*dec_550_intr_establish __P((void *, pci_intr_handle_t,
    108  1.1  thorpej 	    int, int (*func)(void *), void *));
    109  1.1  thorpej void	dec_550_intr_disestablish __P((void *, void *));
    110  1.1  thorpej 
    111  1.1  thorpej void	*dec_550_pciide_compat_intr_establish __P((void *, struct device *,
    112  1.1  thorpej 	    struct pci_attach_args *, int, int (*)(void *), void *));
    113  1.1  thorpej 
    114  1.1  thorpej #define	DEC_550_PCI_IRQ_BEGIN	8
    115  1.1  thorpej #define	DEC_550_MAX_IRQ		48
    116  1.1  thorpej #define	PCI_STRAY_MAX		5
    117  1.1  thorpej 
    118  1.1  thorpej struct alpha_shared_intr *dec_550_pci_intr;
    119  1.1  thorpej #ifdef EVCNT_COUNTERS
    120  1.1  thorpej struct evcnt dec_550_intr_evcnt;
    121  1.1  thorpej #endif
    122  1.1  thorpej 
    123  1.1  thorpej void	dec_550_iointr __P((void *framep, unsigned long vec));
    124  1.1  thorpej void	dec_550_intr_enable __P((int irq));
    125  1.1  thorpej void	dec_550_intr_disable __P((int irq));
    126  1.1  thorpej 
    127  1.1  thorpej u_int64_t *dec_550_int_mask_reg;
    128  1.1  thorpej 
    129  1.1  thorpej void
    130  1.1  thorpej pci_550_pickintr(ccp)
    131  1.1  thorpej 	struct cia_config *ccp;
    132  1.1  thorpej {
    133  1.1  thorpej 	bus_space_tag_t iot = &ccp->cc_iot;
    134  1.1  thorpej 	pci_chipset_tag_t pc = &ccp->cc_pc;
    135  1.1  thorpej 	int i;
    136  1.1  thorpej 
    137  1.1  thorpej         pc->pc_intr_v = ccp;
    138  1.1  thorpej         pc->pc_intr_map = dec_550_intr_map;
    139  1.1  thorpej         pc->pc_intr_string = dec_550_intr_string;
    140  1.1  thorpej         pc->pc_intr_establish = dec_550_intr_establish;
    141  1.1  thorpej         pc->pc_intr_disestablish = dec_550_intr_disestablish;
    142  1.1  thorpej 
    143  1.1  thorpej 	pc->pc_pciide_compat_intr_establish =
    144  1.1  thorpej 	    dec_550_pciide_compat_intr_establish;
    145  1.1  thorpej 
    146  1.1  thorpej 	/*
    147  1.1  thorpej 	 * DEC 550's interrupts are enabled via the Pyxis interrupt
    148  1.1  thorpej 	 * mask register.
    149  1.1  thorpej 	 */
    150  1.1  thorpej 	dec_550_int_mask_reg =
    151  1.1  thorpej 	    (u_int64_t *)ALPHA_PHYS_TO_K0SEG(PYXIS_INT_MASK);
    152  1.1  thorpej 
    153  1.1  thorpej 	for (i = DEC_550_PCI_IRQ_BEGIN; i < DEC_550_MAX_IRQ; i++)
    154  1.1  thorpej 		dec_550_intr_disable(i);
    155  1.1  thorpej 
    156  1.1  thorpej 	dec_550_pci_intr = alpha_shared_intr_alloc(DEC_550_MAX_IRQ);
    157  1.1  thorpej 	for (i = 0; i < DEC_550_MAX_IRQ; i++)
    158  1.1  thorpej 		alpha_shared_intr_set_maxstrays(dec_550_pci_intr, i,
    159  1.1  thorpej 			PCI_STRAY_MAX);
    160  1.1  thorpej 
    161  1.1  thorpej #if NSIO
    162  1.1  thorpej 	sio_intr_setup(pc, iot);
    163  1.1  thorpej #endif
    164  1.1  thorpej 
    165  1.1  thorpej 	set_iointr(dec_550_iointr);
    166  1.1  thorpej }
    167  1.1  thorpej 
    168  1.1  thorpej int
    169  1.1  thorpej dec_550_intr_map(ccv, bustag, buspin, line, ihp)
    170  1.1  thorpej         void *ccv;
    171  1.1  thorpej         pcitag_t bustag;
    172  1.1  thorpej         int buspin, line;
    173  1.1  thorpej         pci_intr_handle_t *ihp;
    174  1.1  thorpej {
    175  1.1  thorpej 	struct cia_config *ccp = ccv;
    176  1.1  thorpej 	pci_chipset_tag_t pc = &ccp->cc_pc;
    177  1.1  thorpej 	int bus, device, function;
    178  1.1  thorpej 
    179  1.1  thorpej 	if (buspin == 0) {
    180  1.1  thorpej 		/* No IRQ used. */
    181  1.1  thorpej 		return 1;
    182  1.1  thorpej 	}
    183  1.1  thorpej 	if (buspin > 4) {
    184  1.1  thorpej 		printf("dec_550_intr_map: bad interrupt pin %d\n", buspin);
    185  1.1  thorpej 		return 1;
    186  1.1  thorpej 	}
    187  1.1  thorpej 
    188  1.1  thorpej 	alpha_pci_decompose_tag(pc, bustag, &bus, &device, &function);
    189  1.1  thorpej 
    190  1.1  thorpej 	/*
    191  1.5  thorpej 	 * There are two main variants of Miata: Miata 1 (Intel SIO)
    192  1.5  thorpej 	 * and Miata {1.5,2} (Cypress).
    193  1.5  thorpej 	 *
    194  1.5  thorpej 	 * The Miata 1 has a CMD PCI IDE wired to compatibility mode at
    195  1.5  thorpej 	 * device 4 of bus 0.  This variant apparently also has the
    196  1.5  thorpej 	 * Pyxis DMA bug.
    197  1.5  thorpej 	 *
    198  1.5  thorpej 	 * On the Miata 1.5 and Miata 2, the Cypress PCI-ISA bridge lives
    199  1.5  thorpej 	 * on device 7 of bus 0.  This device has PCI IDE wired to
    200  1.5  thorpej 	 * compatibility mode on functions 1 and 2.
    201  1.5  thorpej 	 *
    202  1.5  thorpej 	 * There will be no interrupt mapping for these devices, so just
    203  1.5  thorpej 	 * bail out now.
    204  1.1  thorpej 	 */
    205  1.5  thorpej 	if (bus == 0) {
    206  1.5  thorpej 		if ((hwrpb->rpb_variation & SV_ST_MASK) < SV_ST_MIATA_1_5) {
    207  1.5  thorpej 			/* Miata 1 */
    208  1.5  thorpej 			if (device == 7)
    209  1.5  thorpej 				panic("dec_550_intr_map: SIO device");
    210  1.5  thorpej 			else if (device == 4)
    211  1.5  thorpej 				return (1);
    212  1.5  thorpej 		} else {
    213  1.5  thorpej 			/* Miata 1.5 or Miata 2 */
    214  1.5  thorpej 			if (device == 7) {
    215  1.5  thorpej 				if (function == 0)
    216  1.5  thorpej 					panic("dec_550_intr_map: SIO device");
    217  1.5  thorpej 				return (1);
    218  1.5  thorpej 			}
    219  1.5  thorpej 		}
    220  1.1  thorpej 	}
    221  1.1  thorpej 
    222  1.1  thorpej 	/*
    223  1.1  thorpej 	 * The console places the interrupt mapping in the "line" value.
    224  1.1  thorpej 	 * A value of (char)-1 indicates there is no mapping.
    225  1.1  thorpej 	 */
    226  1.1  thorpej 	if (line == 0xff) {
    227  1.1  thorpej 		printf("dec_550_intr_map: no mapping for %d/%d/%d\n",
    228  1.1  thorpej 		    bus, device, function);
    229  1.1  thorpej 		return (1);
    230  1.1  thorpej 	}
    231  1.1  thorpej 
    232  1.1  thorpej 	/* Account for the PCI interrupt offset. */
    233  1.1  thorpej 	line += DEC_550_PCI_IRQ_BEGIN;
    234  1.1  thorpej 
    235  1.1  thorpej 	if (line >= DEC_550_MAX_IRQ)
    236  1.1  thorpej 		panic("dec_550_intr_map: dec 550 irq too large (%d)\n",
    237  1.1  thorpej 		    line);
    238  1.1  thorpej 
    239  1.1  thorpej 	*ihp = line;
    240  1.1  thorpej 	return (0);
    241  1.1  thorpej }
    242  1.1  thorpej 
    243  1.1  thorpej const char *
    244  1.1  thorpej dec_550_intr_string(ccv, ih)
    245  1.1  thorpej 	void *ccv;
    246  1.1  thorpej 	pci_intr_handle_t ih;
    247  1.1  thorpej {
    248  1.1  thorpej #if 0
    249  1.1  thorpej 	struct cia_config *ccp = ccv;
    250  1.1  thorpej #endif
    251  1.1  thorpej 	static char irqstr[16];		/* 12 + 2 + NULL + sanity */
    252  1.1  thorpej 
    253  1.1  thorpej 	if (ih >= DEC_550_MAX_IRQ)
    254  1.1  thorpej 		panic("dec_550_intr_string: bogus 550 IRQ 0x%x\n", ih);
    255  1.1  thorpej 	sprintf(irqstr, "dec 550 irq %d", ih);
    256  1.1  thorpej 	return (irqstr);
    257  1.1  thorpej }
    258  1.1  thorpej 
    259  1.1  thorpej void *
    260  1.1  thorpej dec_550_intr_establish(ccv, ih, level, func, arg)
    261  1.1  thorpej 	void *ccv, *arg;
    262  1.1  thorpej 	pci_intr_handle_t ih;
    263  1.1  thorpej 	int level;
    264  1.1  thorpej 	int (*func) __P((void *));
    265  1.1  thorpej {
    266  1.1  thorpej #if 0
    267  1.1  thorpej 	struct cia_config *ccp = ccv;
    268  1.1  thorpej #endif
    269  1.1  thorpej 	void *cookie;
    270  1.1  thorpej 
    271  1.1  thorpej 	if (ih >= DEC_550_MAX_IRQ)
    272  1.1  thorpej 		panic("dec_550_intr_establish: bogus dec 550 IRQ 0x%x\n", ih);
    273  1.1  thorpej 
    274  1.1  thorpej 	cookie = alpha_shared_intr_establish(dec_550_pci_intr, ih, IST_LEVEL,
    275  1.1  thorpej 	    level, func, arg, "dec 550 irq");
    276  1.1  thorpej 
    277  1.1  thorpej 	if (cookie != NULL && alpha_shared_intr_isactive(dec_550_pci_intr, ih))
    278  1.1  thorpej 		dec_550_intr_enable(ih);
    279  1.1  thorpej 	return (cookie);
    280  1.1  thorpej }
    281  1.1  thorpej 
    282  1.1  thorpej void
    283  1.1  thorpej dec_550_intr_disestablish(ccv, cookie)
    284  1.1  thorpej         void *ccv, *cookie;
    285  1.1  thorpej {
    286  1.1  thorpej #if 0
    287  1.1  thorpej 	struct cia_config *ccp = ccv;
    288  1.1  thorpej #endif
    289  1.1  thorpej 
    290  1.1  thorpej 	panic("dec_550_intr_disestablish not implemented"); /* XXX */
    291  1.1  thorpej }
    292  1.1  thorpej 
    293  1.1  thorpej void *
    294  1.1  thorpej dec_550_pciide_compat_intr_establish(v, dev, pa, chan, func, arg)
    295  1.1  thorpej 	void *v;
    296  1.1  thorpej 	struct device *dev;
    297  1.1  thorpej 	struct pci_attach_args *pa;
    298  1.1  thorpej 	int chan;
    299  1.1  thorpej 	int (*func) __P((void *));
    300  1.1  thorpej 	void *arg;
    301  1.1  thorpej {
    302  1.1  thorpej 	pci_chipset_tag_t pc = pa->pa_pc;
    303  1.1  thorpej 	void *cookie = NULL;
    304  1.1  thorpej 	int bus, irq;
    305  1.1  thorpej 
    306  1.1  thorpej 	alpha_pci_decompose_tag(pc, pa->pa_tag, &bus, NULL, NULL);
    307  1.1  thorpej 
    308  1.1  thorpej 	/*
    309  1.1  thorpej 	 * If this isn't PCI bus #0, all bets are off.
    310  1.1  thorpej 	 */
    311  1.1  thorpej 	if (bus != 0)
    312  1.1  thorpej 		return (NULL);
    313  1.1  thorpej 
    314  1.1  thorpej 	irq = PCIIDE_COMPAT_IRQ(chan);
    315  1.1  thorpej #if NSIO
    316  1.1  thorpej 	cookie = sio_intr_establish(NULL /*XXX*/, irq, IST_EDGE, IPL_BIO,
    317  1.1  thorpej 	    func, arg);
    318  1.1  thorpej #endif
    319  1.1  thorpej 	return (cookie);
    320  1.1  thorpej }
    321  1.1  thorpej 
    322  1.1  thorpej void
    323  1.1  thorpej dec_550_iointr(framep, vec)
    324  1.1  thorpej 	void *framep;
    325  1.1  thorpej 	unsigned long vec;
    326  1.1  thorpej {
    327  1.1  thorpej 	int irq;
    328  1.1  thorpej 
    329  1.1  thorpej 	if (vec >= 0x900) {
    330  1.1  thorpej 		irq = ((vec - 0x900) >> 4) + DEC_550_PCI_IRQ_BEGIN;
    331  1.1  thorpej 
    332  1.1  thorpej 		if (irq >= DEC_550_MAX_IRQ)
    333  1.1  thorpej 			panic("550_iointr: vec 0x%x out of range\n", vec);
    334  1.1  thorpej 
    335  1.1  thorpej #ifdef EVCNT_COUNTERS
    336  1.1  thorpej 		dec_550_intr_evcnt.ev_count++;
    337  1.1  thorpej #else
    338  1.1  thorpej 		if (DEC_550_MAX_IRQ != INTRCNT_DEC_550_IRQ_LEN)
    339  1.1  thorpej 			panic("dec_550 interrupt counter sizes inconsistent");
    340  1.1  thorpej 		intrcnt[INTRCNT_DEC_550_IRQ + irq]++;
    341  1.1  thorpej #endif
    342  1.1  thorpej 
    343  1.1  thorpej 		if (!alpha_shared_intr_dispatch(dec_550_pci_intr, irq)) {
    344  1.1  thorpej 			alpha_shared_intr_stray(dec_550_pci_intr, irq,
    345  1.1  thorpej 			    "dec 550 irq");
    346  1.1  thorpej 			if (dec_550_pci_intr[irq].intr_nstrays ==
    347  1.1  thorpej 			    dec_550_pci_intr[irq].intr_maxstrays)
    348  1.1  thorpej 				dec_550_intr_disable(irq);
    349  1.1  thorpej 		}
    350  1.1  thorpej 		return;
    351  1.1  thorpej 	}
    352  1.1  thorpej #if NSIO
    353  1.1  thorpej 	if (vec >= 0x800) {
    354  1.1  thorpej 		sio_iointr(framep, vec);
    355  1.1  thorpej 		return;
    356  1.1  thorpej 	}
    357  1.1  thorpej #endif
    358  1.1  thorpej 	panic("dec_550_iointr: weird vec 0x%x\n", vec);
    359  1.1  thorpej }
    360  1.1  thorpej 
    361  1.1  thorpej void
    362  1.1  thorpej dec_550_intr_enable(irq)
    363  1.1  thorpej 	int irq;
    364  1.1  thorpej {
    365  1.1  thorpej 	u_int64_t imask;
    366  1.1  thorpej 	int s;
    367  1.1  thorpej 
    368  1.1  thorpej #if 1
    369  1.1  thorpej 	printf("dec_550_intr_enable: enabling %d\n", irq);
    370  1.1  thorpej #endif
    371  1.1  thorpej 
    372  1.1  thorpej 	s = splhigh();
    373  1.1  thorpej 	alpha_mb();
    374  1.1  thorpej 	imask = *dec_550_int_mask_reg;
    375  1.1  thorpej 	imask |= (1UL << irq);
    376  1.1  thorpej 	*dec_550_int_mask_reg = imask;
    377  1.1  thorpej 	alpha_mb();
    378  1.1  thorpej 	splx(s);
    379  1.1  thorpej }
    380  1.1  thorpej 
    381  1.1  thorpej void
    382  1.1  thorpej dec_550_intr_disable(irq)
    383  1.1  thorpej 	int irq;
    384  1.1  thorpej {
    385  1.1  thorpej 	u_int64_t imask;
    386  1.1  thorpej 	int s;
    387  1.1  thorpej 
    388  1.1  thorpej #if 1
    389  1.1  thorpej 	printf("dec_550_intr_disable: disabling %d\n", irq);
    390  1.1  thorpej #endif
    391  1.1  thorpej 
    392  1.1  thorpej 	s = splhigh();
    393  1.1  thorpej 	alpha_mb();
    394  1.1  thorpej 	imask = *dec_550_int_mask_reg;
    395  1.1  thorpej 	imask &= ~(1UL << irq);
    396  1.1  thorpej 	*dec_550_int_mask_reg = imask;
    397  1.1  thorpej 	alpha_mb();
    398  1.1  thorpej 	splx(s);
    399  1.1  thorpej }
    400