FreeBSD/Linux Kernel Cross Reference
sys/i386/isa/intr_machdep.c

     /*-
      * Copyright (c) 1991 The Regents of the University of California.
      * All rights reserved.
      *
      * This code is derived from software contributed to Berkeley by
      * William Jolitz.
      *
      * Redistribution and use in source and binary forms, with or without
      * modification, are permitted provided that the following conditions
     * are met:
     * 1. Redistributions of source code must retain the above copyright
     *    notice, this list of conditions and the following disclaimer.
     * 2. Redistributions in binary form must reproduce the above copyright
     *    notice, this list of conditions and the following disclaimer in the
     *    documentation and/or other materials provided with the distribution.
     * 3. All advertising materials mentioning features or use of this software
     *    must display the following acknowledgement:
     *      This product includes software developed by the University of
     *      California, Berkeley and its contributors.
     * 4. Neither the name of the University nor the names of its contributors
     *    may be used to endorse or promote products derived from this software
     *    without specific prior written permission.
     *
     * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     * SUCH DAMAGE.
     *
     *      from: @(#)isa.c 7.2 (Berkeley) 5/13/91
     * $FreeBSD: releng/5.1/sys/i386/isa/intr_machdep.c 114803 2003-05-07 17:21:38Z jhb $
     */
    
    #include "opt_auto_eoi.h"
    #include "opt_isa.h"
    #include "opt_mca.h"
    
    #include <sys/param.h>
    #include <sys/bus.h> 
    #include <sys/errno.h>
    #include <sys/interrupt.h>
    #include <sys/kernel.h>
    #include <sys/kthread.h>
    #include <sys/lock.h>
    #include <sys/malloc.h>
    #include <sys/module.h>
    #include <sys/mutex.h>
    #include <sys/proc.h>
    #include <sys/syslog.h>
    #include <sys/systm.h>
    #include <sys/unistd.h>
    
    #include <machine/md_var.h>
    #include <machine/segments.h>
    
    #if defined(APIC_IO)
    #include <machine/smptests.h>                   /** FAST_HI */
    #include <machine/smp.h>
    #include <machine/resource.h>
    #endif /* APIC_IO */
    #ifdef PC98
    #include <pc98/pc98/pc98.h>
    #include <pc98/pc98/pc98_machdep.h>
    #include <pc98/pc98/epsonio.h>
    #else
    #include <i386/isa/isa.h>
    #endif
    #include <i386/isa/icu.h>
    
    #ifdef DEV_ISA
    #include <isa/isavar.h>
    #endif
    #include <i386/isa/intr_machdep.h>
    #include <sys/interrupt.h>
    #ifdef APIC_IO
    #include <machine/clock.h>
    #endif
    
    #ifdef DEV_MCA
    #include <i386/bios/mca_machdep.h>
    #endif
    
    /*
     * Per-interrupt data.
     */
    u_long  *intr_countp[ICU_LEN];          /* pointers to interrupt counters */
    driver_intr_t   *intr_handler[ICU_LEN]; /* first level interrupt handler */
    struct   ithd *ithds[ICU_LEN];          /* real interrupt handler */
    void    *intr_unit[ICU_LEN];
    
    static struct   mtx ithds_table_lock;   /* protect the ithds table */
    
    static inthand_t *fastintr[ICU_LEN] = {
           IDTVEC(fastintr0), IDTVEC(fastintr1),
           IDTVEC(fastintr2), IDTVEC(fastintr3),
           IDTVEC(fastintr4), IDTVEC(fastintr5),
           IDTVEC(fastintr6), IDTVEC(fastintr7),
           IDTVEC(fastintr8), IDTVEC(fastintr9),
           IDTVEC(fastintr10), IDTVEC(fastintr11),
           IDTVEC(fastintr12), IDTVEC(fastintr13),
           IDTVEC(fastintr14), IDTVEC(fastintr15),
   #if defined(APIC_IO)
           IDTVEC(fastintr16), IDTVEC(fastintr17),
           IDTVEC(fastintr18), IDTVEC(fastintr19),
           IDTVEC(fastintr20), IDTVEC(fastintr21),
           IDTVEC(fastintr22), IDTVEC(fastintr23),
           IDTVEC(fastintr24), IDTVEC(fastintr25),
           IDTVEC(fastintr26), IDTVEC(fastintr27),
           IDTVEC(fastintr28), IDTVEC(fastintr29),
           IDTVEC(fastintr30), IDTVEC(fastintr31),
   #endif /* APIC_IO */
   };
   
   static unpendhand_t *fastunpend[ICU_LEN] = {
           IDTVEC(fastunpend0), IDTVEC(fastunpend1),
           IDTVEC(fastunpend2), IDTVEC(fastunpend3),
           IDTVEC(fastunpend4), IDTVEC(fastunpend5),
           IDTVEC(fastunpend6), IDTVEC(fastunpend7),
           IDTVEC(fastunpend8), IDTVEC(fastunpend9),
           IDTVEC(fastunpend10), IDTVEC(fastunpend11),
           IDTVEC(fastunpend12), IDTVEC(fastunpend13),
           IDTVEC(fastunpend14), IDTVEC(fastunpend15),
   #if defined(APIC_IO)
           IDTVEC(fastunpend16), IDTVEC(fastunpend17),
           IDTVEC(fastunpend18), IDTVEC(fastunpend19),
           IDTVEC(fastunpend20), IDTVEC(fastunpend21),
           IDTVEC(fastunpend22), IDTVEC(fastunpend23),
           IDTVEC(fastunpend24), IDTVEC(fastunpend25),
           IDTVEC(fastunpend26), IDTVEC(fastunpend27),
           IDTVEC(fastunpend28), IDTVEC(fastunpend29),
           IDTVEC(fastunpend30), IDTVEC(fastunpend31),
   #endif /* APIC_IO */
   };
   
   static inthand_t *slowintr[ICU_LEN] = {
           IDTVEC(intr0), IDTVEC(intr1), IDTVEC(intr2), IDTVEC(intr3),
           IDTVEC(intr4), IDTVEC(intr5), IDTVEC(intr6), IDTVEC(intr7),
           IDTVEC(intr8), IDTVEC(intr9), IDTVEC(intr10), IDTVEC(intr11),
           IDTVEC(intr12), IDTVEC(intr13), IDTVEC(intr14), IDTVEC(intr15),
   #if defined(APIC_IO)
           IDTVEC(intr16), IDTVEC(intr17), IDTVEC(intr18), IDTVEC(intr19),
           IDTVEC(intr20), IDTVEC(intr21), IDTVEC(intr22), IDTVEC(intr23),
           IDTVEC(intr24), IDTVEC(intr25), IDTVEC(intr26), IDTVEC(intr27),
           IDTVEC(intr28), IDTVEC(intr29), IDTVEC(intr30), IDTVEC(intr31),
   #endif /* APIC_IO */
   };
   
   static driver_intr_t isa_strayintr;
   
   static void     ithds_init(void *dummy);
   static void     ithread_enable(int vector);
   static void     ithread_disable(int vector);
   static void     init_i8259(void);
   
   #ifdef PC98
   #define NMI_PARITY 0x04
   #define NMI_EPARITY 0x02
   #else
   #define NMI_PARITY (1 << 7)
   #define NMI_IOCHAN (1 << 6)
   #define ENMI_WATCHDOG (1 << 7)
   #define ENMI_BUSTIMER (1 << 6)
   #define ENMI_IOSTATUS (1 << 5)
   #endif
   
   #ifdef DEV_ISA
   /*
    * Bus attachment for the ISA PIC.
    */
   static struct isa_pnp_id atpic_ids[] = {
           { 0x0000d041 /* PNP0000 */, "AT interrupt controller" },
           { 0 }
   };
   
   static int
   atpic_probe(device_t dev)
   {
           int result;
           
           if ((result = ISA_PNP_PROBE(device_get_parent(dev), dev, atpic_ids)) <= 0)
                   device_quiet(dev);
           return(result);
   }
   
   /*
    * In the APIC_IO case we might be granted IRQ 2, as this is typically
    * consumed by chaining between the two PIC components.  If we're using
    * the APIC, however, this may not be the case, and as such we should
    * free the resource.  (XXX untested)
    *
    * The generic ISA attachment code will handle allocating any other resources
    * that we don't explicitly claim here.
    */
   static int
   atpic_attach(device_t dev)
   {
   #ifdef APIC_IO
           int             rid;
           struct resource *res;
   
           /* try to allocate our IRQ and then free it */
           rid = 0;
           res = bus_alloc_resource(dev, SYS_RES_IRQ, &rid, 0, ~0, 1, 0);
           if (res != NULL)
                   bus_release_resource(dev, SYS_RES_IRQ, rid, res);
   #endif
           return(0);
   }
   
   static device_method_t atpic_methods[] = {
           /* Device interface */
           DEVMETHOD(device_probe,         atpic_probe),
           DEVMETHOD(device_attach,        atpic_attach),
           DEVMETHOD(device_detach,        bus_generic_detach),
           DEVMETHOD(device_shutdown,      bus_generic_shutdown),
           DEVMETHOD(device_suspend,       bus_generic_suspend),
           DEVMETHOD(device_resume,        bus_generic_resume),
           { 0, 0 }
   };
   
   static driver_t atpic_driver = {
           "atpic",
           atpic_methods,
           1,              /* no softc */
   };
   
   static devclass_t atpic_devclass;
   
   DRIVER_MODULE(atpic, isa, atpic_driver, atpic_devclass, 0, 0);
   DRIVER_MODULE(atpic, acpi, atpic_driver, atpic_devclass, 0, 0);
   #endif /* DEV_ISA */
   
   /*
    * Handle a NMI, possibly a machine check.
    * return true to panic system, false to ignore.
    */
   int
   isa_nmi(cd)
           int cd;
   {
           int retval = 0;
   #ifdef PC98
           int port = inb(0x33);
   
           log(LOG_CRIT, "NMI PC98 port = %x\n", port);
           if (epson_machine_id == 0x20)
                   epson_outb(0xc16, epson_inb(0xc16) | 0x1);
           if (port & NMI_PARITY) {
                   log(LOG_CRIT, "BASE RAM parity error, likely hardware failure.");
                   retval = 1;
           } else if (port & NMI_EPARITY) {
                   log(LOG_CRIT, "EXTENDED RAM parity error, likely hardware failure.");
                   retval = 1;
           } else {
                   log(LOG_CRIT, "\nNMI Resume ??\n");
           }
   #else /* IBM-PC */
           int isa_port = inb(0x61);
           int eisa_port = inb(0x461);
   
           log(LOG_CRIT, "NMI ISA %x, EISA %x\n", isa_port, eisa_port);
   #ifdef DEV_MCA
           if (MCA_system && mca_bus_nmi())
                   return(0);
   #endif
           
           if (isa_port & NMI_PARITY) {
                   log(LOG_CRIT, "RAM parity error, likely hardware failure.");
                   retval = 1;
           }
   
           if (isa_port & NMI_IOCHAN) {
                   log(LOG_CRIT, "I/O channel check, likely hardware failure.");
                   retval = 1;
           }
   
           /*
            * On a real EISA machine, this will never happen.  However it can
            * happen on ISA machines which implement XT style floating point
            * error handling (very rare).  Save them from a meaningless panic.
            */
           if (eisa_port == 0xff)
                   return(retval);
   
           if (eisa_port & ENMI_WATCHDOG) {
                   log(LOG_CRIT, "EISA watchdog timer expired, likely hardware failure.");
                   retval = 1;
           }
   
           if (eisa_port & ENMI_BUSTIMER) {
                   log(LOG_CRIT, "EISA bus timeout, likely hardware failure.");
                   retval = 1;
           }
   
           if (eisa_port & ENMI_IOSTATUS) {
                   log(LOG_CRIT, "EISA I/O port status error.");
                   retval = 1;
           }
   #endif
           return(retval);
   }
   
   /*
    *  ICU reinitialize when ICU configuration has lost.
    */
   void
   icu_reinit()
   {
           int i;
           register_t crit;
   
           crit = intr_disable();
           mtx_lock_spin(&icu_lock);
           init_i8259();
           for(i=0;i<ICU_LEN;i++)
                   if(intr_handler[i] != isa_strayintr)
                           INTREN(1<<i);
           mtx_unlock_spin(&icu_lock);
           intr_restore(crit);
   }
   
   /*
    * Create a default interrupt table to avoid problems caused by
    * spurious interrupts during configuration of kernel, then setup
    * interrupt control unit.
    */
   void
   isa_defaultirq()
   {
           int i;
           register_t crit;
   
           /* icu vectors */
           for (i = 0; i < ICU_LEN; i++)
                   icu_unset(i, (driver_intr_t *)NULL);
           crit = intr_disable();
           mtx_lock_spin(&icu_lock);
           init_i8259();
           mtx_unlock_spin(&icu_lock);
           intr_restore(crit);
   }
   
   
   /* 
    *initialize 8259's
    */
   static void
   init_i8259()
   {
   
   #ifdef DEV_MCA
           if (MCA_system)
                   outb(IO_ICU1, 0x19);            /* reset; program device, four bytes */
           else
   #endif
                   outb(IO_ICU1, 0x11);            /* reset; program device, four bytes */
   
           outb(IO_ICU1+ICU_IMR_OFFSET, NRSVIDT);  /* starting at this vector index */
           outb(IO_ICU1+ICU_IMR_OFFSET, IRQ_SLAVE);                /* slave on line 7 */
   #ifdef PC98
   #ifdef AUTO_EOI_1
           outb(IO_ICU1+ICU_IMR_OFFSET, 0x1f);             /* (master) auto EOI, 8086 mode */
   #else
           outb(IO_ICU1+ICU_IMR_OFFSET, 0x1d);             /* (master) 8086 mode */
   #endif
   #else /* IBM-PC */
   #ifdef AUTO_EOI_1
           outb(IO_ICU1+ICU_IMR_OFFSET, 2 | 1);            /* auto EOI, 8086 mode */
   #else
           outb(IO_ICU1+ICU_IMR_OFFSET, 1);                /* 8086 mode */
   #endif
   #endif /* PC98 */
           outb(IO_ICU1+ICU_IMR_OFFSET, 0xff);             /* leave interrupts masked */
           outb(IO_ICU1, 0x0a);            /* default to IRR on read */
   #ifndef PC98
           outb(IO_ICU1, 0xc0 | (3 - 1));  /* pri order 3-7, 0-2 (com2 first) */
   #endif /* !PC98 */
   
   #ifdef DEV_MCA
           if (MCA_system)
                   outb(IO_ICU2, 0x19);            /* reset; program device, four bytes */
           else
   #endif
                   outb(IO_ICU2, 0x11);            /* reset; program device, four bytes */
   
           outb(IO_ICU2+ICU_IMR_OFFSET, NRSVIDT+8); /* staring at this vector index */
           outb(IO_ICU2+ICU_IMR_OFFSET, ICU_SLAVEID);         /* my slave id is 7 */
   #ifdef PC98
           outb(IO_ICU2+ICU_IMR_OFFSET,9);              /* 8086 mode */
   #else /* IBM-PC */
   #ifdef AUTO_EOI_2
           outb(IO_ICU2+ICU_IMR_OFFSET, 2 | 1);            /* auto EOI, 8086 mode */
   #else
           outb(IO_ICU2+ICU_IMR_OFFSET,1);         /* 8086 mode */
   #endif
   #endif /* PC98 */
           outb(IO_ICU2+ICU_IMR_OFFSET, 0xff);          /* leave interrupts masked */
           outb(IO_ICU2, 0x0a);            /* default to IRR on read */
   }
   
   /*
    * Caught a stray interrupt, notify
    */
   static void
   isa_strayintr(vcookiep)
           void *vcookiep;
   {
           int intr = (void **)vcookiep - &intr_unit[0];
   
           /*
            * XXX TODO print a different message for #7 if it is for a
            * glitch.  Glitches can be distinguished from real #7's by
            * testing that the in-service bit is _not_ set.  The test
            * must be done before sending an EOI so it can't be done if
            * we are using AUTO_EOI_1.
            */
           if (intrcnt[1 + intr] <= 5)
                   log(LOG_ERR, "stray irq %d\n", intr);
           if (intrcnt[1 + intr] == 5)
                   log(LOG_CRIT,
                       "too many stray irq %d's; not logging any more\n", intr);
   }
   
   #ifdef DEV_ISA
   /*
    * Return a bitmap of the current interrupt requests.  This is 8259-specific
    * and is only suitable for use at probe time.
    */
   intrmask_t
   isa_irq_pending()
   {
           u_char irr1;
           u_char irr2;
   
           irr1 = inb(IO_ICU1);
           irr2 = inb(IO_ICU2);
           return ((irr2 << 8) | irr1);
   }
   #endif
   
   /*
    * Update intrnames array with the specified name.  This is used by
    * vmstat(8) and the like.
    */
   static void
   update_intrname(int intr, const char *name)
   {
           char buf[32];
           char *cp;
           int name_index, off, strayintr;
   
           /*
            * Initialise strings for bitbucket and stray interrupt counters.
            * These have statically allocated indices 0 and 1 through ICU_LEN.
            */
           if (intrnames[0] == '\0') {
                   off = sprintf(intrnames, "???") + 1;
                   for (strayintr = 0; strayintr < ICU_LEN; strayintr++)
                           off += sprintf(intrnames + off, "stray irq%d",
                               strayintr) + 1;
           }
   
           if (name == NULL)
                   name = "???";
           if (snprintf(buf, sizeof(buf), "%s irq%d", name, intr) >= sizeof(buf))
                   goto use_bitbucket;
   
           /*
            * Search for `buf' in `intrnames'.  In the usual case when it is
            * not found, append it to the end if there is enough space (the \0
            * terminator for the previous string, if any, becomes a separator).
            */
           for (cp = intrnames, name_index = 0;
               cp != eintrnames && name_index < NR_INTRNAMES;
               cp += strlen(cp) + 1, name_index++) {
                   if (*cp == '\0') {
                           if (strlen(buf) >= eintrnames - cp)
                                   break;
                           strcpy(cp, buf);
                           goto found;
                   }
                   if (strcmp(cp, buf) == 0)
                           goto found;
           }
   
   use_bitbucket:
           printf("update_intrname: counting %s irq%d as %s\n", name, intr,
               intrnames);
           name_index = 0;
   found:
           intr_countp[intr] = &intrcnt[name_index];
   }
   
   int
   icu_setup(int intr, driver_intr_t *handler, void *arg, int flags)
   {
   #ifdef FAST_HI
           int             select;         /* the select register is 8 bits */
           int             vector;
           u_int32_t       value;          /* the window register is 32 bits */
   #endif /* FAST_HI */
           register_t      crit;
   
   #if defined(APIC_IO)
           if ((u_int)intr >= ICU_LEN)     /* no 8259 SLAVE to ignore */
   #else
           if ((u_int)intr >= ICU_LEN || intr == ICU_SLAVEID)
   #endif /* APIC_IO */
                   return (EINVAL);
   #if 0
           if (intr_handler[intr] != isa_strayintr)
                   return (EBUSY);
   #endif
   
           crit = intr_disable();
           mtx_lock_spin(&icu_lock);
           intr_handler[intr] = handler;
           intr_unit[intr] = arg;
   #ifdef FAST_HI
           if (flags & INTR_FAST) {
                   vector = TPR_FAST_INTS + intr;
                   setidt(vector, fastintr[intr],
                          SDT_SYS386IGT, SEL_KPL, GSEL(GCODE_SEL, SEL_KPL));
           }
           else {
                   vector = TPR_SLOW_INTS + intr;
                   setidt(vector, slowintr[intr],
                          SDT_SYS386IGT, SEL_KPL, GSEL(GCODE_SEL, SEL_KPL));
           }
   #ifdef APIC_INTR_REORDER
           set_lapic_isrloc(intr, vector);
   #endif
           /*
            * Reprogram the vector in the IO APIC.
            */
           if (int_to_apicintpin[intr].ioapic >= 0) {
                   select = int_to_apicintpin[intr].redirindex;
                   value = io_apic_read(int_to_apicintpin[intr].ioapic, 
                                        select) & ~IOART_INTVEC;
                   io_apic_write(int_to_apicintpin[intr].ioapic, 
                                 select, value | vector);
           }
   #else
           setidt(ICU_OFFSET + intr,
                  flags & INTR_FAST ? fastintr[intr] : slowintr[intr],
                  SDT_SYS386IGT, SEL_KPL, GSEL(GCODE_SEL, SEL_KPL));
   #endif /* FAST_HI */
           INTREN(1 << intr);
           mtx_unlock_spin(&icu_lock);
           intr_restore(crit);
           return (0);
   }
   
   /*
    * Dissociate an interrupt handler from an IRQ and set the handler to
    * the stray interrupt handler.  The 'handler' parameter is used only
    * for consistency checking.
    */
   int
   icu_unset(intr, handler)
           int     intr;
           driver_intr_t *handler;
   {
           register_t crit;
   
           if ((u_int)intr >= ICU_LEN || handler != intr_handler[intr])
                   return (EINVAL);
   
           crit = intr_disable();
           mtx_lock_spin(&icu_lock);
           INTRDIS(1 << intr);
           intr_countp[intr] = &intrcnt[1 + intr];
           intr_handler[intr] = isa_strayintr;
           intr_unit[intr] = &intr_unit[intr];
   #ifdef FAST_HI_XXX
           /* XXX how do I re-create dvp here? */
           setidt(flags & INTR_FAST ? TPR_FAST_INTS + intr : TPR_SLOW_INTS + intr,
               slowintr[intr], SDT_SYS386IGT, SEL_KPL, GSEL(GCODE_SEL, SEL_KPL));
   #else /* FAST_HI */
   #ifdef APIC_INTR_REORDER
           set_lapic_isrloc(intr, ICU_OFFSET + intr);
   #endif
           setidt(ICU_OFFSET + intr, slowintr[intr], SDT_SYS386IGT, SEL_KPL,
               GSEL(GCODE_SEL, SEL_KPL));
   #endif /* FAST_HI */
           mtx_unlock_spin(&icu_lock);
           intr_restore(crit);
           return (0);
   }
   
   static void
   ithds_init(void *dummy)
   {
   
           mtx_init(&ithds_table_lock, "ithread table lock", NULL, MTX_SPIN);
   }
   SYSINIT(ithds_init, SI_SUB_INTR, SI_ORDER_SECOND, ithds_init, NULL);
   
   static void
   ithread_enable(int vector)
   {
           register_t crit;
   
           crit = intr_disable();
           mtx_lock_spin(&icu_lock);
           INTREN(1 << vector);
           mtx_unlock_spin(&icu_lock);
           intr_restore(crit);
   }
   
   static void
   ithread_disable(int vector)
   {
           register_t crit;
   
           crit = intr_disable();
           mtx_lock_spin(&icu_lock);
           INTRDIS(1 << vector);
           mtx_unlock_spin(&icu_lock);
           intr_restore(crit);
   }
   
   int
   inthand_add(const char *name, int irq, driver_intr_t handler, void *arg,
       enum intr_type flags, void **cookiep)
   {
           struct ithd *ithd;              /* descriptor for the IRQ */
           int errcode = 0;
           int created_ithd = 0;
   
           /*
            * Work around a race where more than one CPU may be registering
            * handlers on the same IRQ at the same time.
            */
           mtx_lock_spin(&ithds_table_lock);
           ithd = ithds[irq];
           mtx_unlock_spin(&ithds_table_lock);
           if (ithd == NULL) {
                   errcode = ithread_create(&ithd, irq, 0, ithread_disable,
                       ithread_enable, "irq%d:", irq);
                   if (errcode)
                           return (errcode);
                   mtx_lock_spin(&ithds_table_lock);
                   if (ithds[irq] == NULL) {
                           ithds[irq] = ithd;
                           created_ithd++;
                           mtx_unlock_spin(&ithds_table_lock);
                   } else {
                           struct ithd *orphan;
   
                           orphan = ithd;
                           ithd = ithds[irq];
                           mtx_unlock_spin(&ithds_table_lock);
                           ithread_destroy(orphan);
                   }
           }
   
           errcode = ithread_add_handler(ithd, name, handler, arg,
               ithread_priority(flags), flags, cookiep);
           
           if ((flags & INTR_FAST) == 0 || errcode)
                   /*
                    * The interrupt process must be in place, but
                    * not necessarily schedulable, before we
                    * initialize the ICU, since it may cause an
                    * immediate interrupt.
                    */
                   if (icu_setup(irq, sched_ithd, arg, flags) != 0)
                           panic("inthand_add: Can't initialize ICU");
   
           if (errcode)
                   return (errcode);
           
           if (flags & INTR_FAST) {
                   errcode = icu_setup(irq, handler, arg, flags);
                   if (errcode && bootverbose)
                           printf("\tinthand_add(irq%d) failed, result=%d\n", 
                                  irq, errcode);
                   if (errcode)
                           return (errcode);
           }
   
           update_intrname(irq, name);
           return (0);
   }
   
   /*
    * Deactivate and remove linked list the interrupt handler descriptor
    * data connected created by an earlier call of inthand_add(), then
    * adjust the interrupt masks if necessary.
    *
    * Return the memory held by the interrupt handler descriptor data
    * structure to the system.  First ensure the handler is not actively
    * in use.
    */
   int
   inthand_remove(void *cookie)
   {
   
           return (ithread_remove_handler(cookie));
   }
   
   void
   call_fast_unpend(int irq)
   {
           fastunpend[irq]();
   }
   

Cache object: 048963f78f3fd1b610bdcd3aedb5d2cf