FreeBSD/Linux Kernel Cross Reference
sys/kern/subr_intr.c

     /*-
      * Copyright (c) 2015-2016 Svatopluk Kraus
      * Copyright (c) 2015-2016 Michal Meloun
      * All rights reserved.
      *
      * 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.
     *
     * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
     */
    
    #include <sys/cdefs.h>
    __FBSDID("$FreeBSD: releng/11.1/sys/kern/subr_intr.c 308382 2016-11-06 18:40:12Z gonzo $");
    
    /*
     *      New-style Interrupt Framework
     *
     *  TODO: - add support for disconnected PICs.
     *        - to support IPI (PPI) enabling on other CPUs if already started.
     *        - to complete things for removable PICs.
     */
    
    #include "opt_ddb.h"
    #include "opt_hwpmc_hooks.h"
    
    #include <sys/param.h>
    #include <sys/systm.h>
    #include <sys/kernel.h>
    #include <sys/syslog.h>
    #include <sys/malloc.h>
    #include <sys/proc.h>
    #include <sys/queue.h>
    #include <sys/bus.h>
    #include <sys/interrupt.h>
    #include <sys/conf.h>
    #include <sys/cpuset.h>
    #include <sys/rman.h>
    #include <sys/sched.h>
    #include <sys/smp.h>
    #ifdef HWPMC_HOOKS
    #include <sys/pmckern.h>
    #endif
    
    #include <machine/atomic.h>
    #include <machine/intr.h>
    #include <machine/cpu.h>
    #include <machine/smp.h>
    #include <machine/stdarg.h>
    
    #ifdef DDB
    #include <ddb/ddb.h>
    #endif
    
    #include "pic_if.h"
    #include "msi_if.h"
    
    #define INTRNAME_LEN    (2*MAXCOMLEN + 1)
    
    #ifdef DEBUG
    #define debugf(fmt, args...) do { printf("%s(): ", __func__);   \
        printf(fmt,##args); } while (0)
    #else
    #define debugf(fmt, args...)
    #endif
    
    MALLOC_DECLARE(M_INTRNG);
    MALLOC_DEFINE(M_INTRNG, "intr", "intr interrupt handling");
    
    /* Main interrupt handler called from assembler -> 'hidden' for C code. */
    void intr_irq_handler(struct trapframe *tf);
    
    /* Root interrupt controller stuff. */
    device_t intr_irq_root_dev;
    static intr_irq_filter_t *irq_root_filter;
    static void *irq_root_arg;
    static u_int irq_root_ipicount;
    
    struct intr_pic_child {
            SLIST_ENTRY(intr_pic_child)      pc_next;
            struct intr_pic                 *pc_pic;
            intr_child_irq_filter_t         *pc_filter;
            void                            *pc_filter_arg;
            uintptr_t                        pc_start;
           uintptr_t                        pc_length;
   };
   
   /* Interrupt controller definition. */
   struct intr_pic {
           SLIST_ENTRY(intr_pic)   pic_next;
           intptr_t                pic_xref;       /* hardware identification */
           device_t                pic_dev;
   #define FLAG_PIC        (1 << 0)
   #define FLAG_MSI        (1 << 1)
           u_int                   pic_flags;
           struct mtx              pic_child_lock;
           SLIST_HEAD(, intr_pic_child) pic_children;
   };
   
   static struct mtx pic_list_lock;
   static SLIST_HEAD(, intr_pic) pic_list;
   
   static struct intr_pic *pic_lookup(device_t dev, intptr_t xref);
   
   /* Interrupt source definition. */
   static struct mtx isrc_table_lock;
   static struct intr_irqsrc *irq_sources[NIRQ];
   u_int irq_next_free;
   
   #ifdef SMP
   static boolean_t irq_assign_cpu = FALSE;
   #endif
   
   /*
    * - 2 counters for each I/O interrupt.
    * - MAXCPU counters for each IPI counters for SMP.
    */
   #ifdef SMP
   #define INTRCNT_COUNT   (NIRQ * 2 + INTR_IPI_COUNT * MAXCPU)
   #else
   #define INTRCNT_COUNT   (NIRQ * 2)
   #endif
   
   /* Data for MI statistics reporting. */
   u_long intrcnt[INTRCNT_COUNT];
   char intrnames[INTRCNT_COUNT * INTRNAME_LEN];
   size_t sintrcnt = sizeof(intrcnt);
   size_t sintrnames = sizeof(intrnames);
   static u_int intrcnt_index;
   
   static struct intr_irqsrc *intr_map_get_isrc(u_int res_id);
   static void intr_map_set_isrc(u_int res_id, struct intr_irqsrc *isrc);
   static struct intr_map_data * intr_map_get_map_data(u_int res_id);
   static void intr_map_copy_map_data(u_int res_id, device_t *dev, intptr_t *xref,
       struct intr_map_data **data);
   
   /*
    *  Interrupt framework initialization routine.
    */
   static void
   intr_irq_init(void *dummy __unused)
   {
   
           SLIST_INIT(&pic_list);
           mtx_init(&pic_list_lock, "intr pic list", NULL, MTX_DEF);
   
           mtx_init(&isrc_table_lock, "intr isrc table", NULL, MTX_DEF);
   }
   SYSINIT(intr_irq_init, SI_SUB_INTR, SI_ORDER_FIRST, intr_irq_init, NULL);
   
   static void
   intrcnt_setname(const char *name, int index)
   {
   
           snprintf(intrnames + INTRNAME_LEN * index, INTRNAME_LEN, "%-*s",
               INTRNAME_LEN - 1, name);
   }
   
   /*
    *  Update name for interrupt source with interrupt event.
    */
   static void
   intrcnt_updatename(struct intr_irqsrc *isrc)
   {
   
           /* QQQ: What about stray counter name? */
           mtx_assert(&isrc_table_lock, MA_OWNED);
           intrcnt_setname(isrc->isrc_event->ie_fullname, isrc->isrc_index);
   }
   
   /*
    *  Virtualization for interrupt source interrupt counter increment.
    */
   static inline void
   isrc_increment_count(struct intr_irqsrc *isrc)
   {
   
           if (isrc->isrc_flags & INTR_ISRCF_PPI)
                   atomic_add_long(&isrc->isrc_count[0], 1);
           else
                   isrc->isrc_count[0]++;
   }
   
   /*
    *  Virtualization for interrupt source interrupt stray counter increment.
    */
   static inline void
   isrc_increment_straycount(struct intr_irqsrc *isrc)
   {
   
           isrc->isrc_count[1]++;
   }
   
   /*
    *  Virtualization for interrupt source interrupt name update.
    */
   static void
   isrc_update_name(struct intr_irqsrc *isrc, const char *name)
   {
           char str[INTRNAME_LEN];
   
           mtx_assert(&isrc_table_lock, MA_OWNED);
   
           if (name != NULL) {
                   snprintf(str, INTRNAME_LEN, "%s: %s", isrc->isrc_name, name);
                   intrcnt_setname(str, isrc->isrc_index);
                   snprintf(str, INTRNAME_LEN, "stray %s: %s", isrc->isrc_name,
                       name);
                   intrcnt_setname(str, isrc->isrc_index + 1);
           } else {
                   snprintf(str, INTRNAME_LEN, "%s:", isrc->isrc_name);
                   intrcnt_setname(str, isrc->isrc_index);
                   snprintf(str, INTRNAME_LEN, "stray %s:", isrc->isrc_name);
                   intrcnt_setname(str, isrc->isrc_index + 1);
           }
   }
   
   /*
    *  Virtualization for interrupt source interrupt counters setup.
    */
   static void
   isrc_setup_counters(struct intr_irqsrc *isrc)
   {
           u_int index;
   
           /*
            *  XXX - it does not work well with removable controllers and
            *        interrupt sources !!!
            */
           index = atomic_fetchadd_int(&intrcnt_index, 2);
           isrc->isrc_index = index;
           isrc->isrc_count = &intrcnt[index];
           isrc_update_name(isrc, NULL);
   }
   
   /*
    *  Virtualization for interrupt source interrupt counters release.
    */
   static void
   isrc_release_counters(struct intr_irqsrc *isrc)
   {
   
           panic("%s: not implemented", __func__);
   }
   
   #ifdef SMP
   /*
    *  Virtualization for interrupt source IPI counters setup.
    */
   u_long *
   intr_ipi_setup_counters(const char *name)
   {
           u_int index, i;
           char str[INTRNAME_LEN];
   
           index = atomic_fetchadd_int(&intrcnt_index, MAXCPU);
           for (i = 0; i < MAXCPU; i++) {
                   snprintf(str, INTRNAME_LEN, "cpu%d:%s", i, name);
                   intrcnt_setname(str, index + i);
           }
           return (&intrcnt[index]);
   }
   #endif
   
   /*
    *  Main interrupt dispatch handler. It's called straight
    *  from the assembler, where CPU interrupt is served.
    */
   void
   intr_irq_handler(struct trapframe *tf)
   {
           struct trapframe * oldframe;
           struct thread * td;
   
           KASSERT(irq_root_filter != NULL, ("%s: no filter", __func__));
   
           PCPU_INC(cnt.v_intr);
           critical_enter();
           td = curthread;
           oldframe = td->td_intr_frame;
           td->td_intr_frame = tf;
           irq_root_filter(irq_root_arg);
           td->td_intr_frame = oldframe;
           critical_exit();
   #ifdef HWPMC_HOOKS
           if (pmc_hook && TRAPF_USERMODE(tf) &&
               (PCPU_GET(curthread)->td_pflags & TDP_CALLCHAIN))
                   pmc_hook(PCPU_GET(curthread), PMC_FN_USER_CALLCHAIN, tf);
   #endif
   }
   
   int
   intr_child_irq_handler(struct intr_pic *parent, uintptr_t irq)
   {
           struct intr_pic_child *child;
           bool found;
   
           found = false;
           mtx_lock_spin(&parent->pic_child_lock);
           SLIST_FOREACH(child, &parent->pic_children, pc_next) {
                   if (child->pc_start <= irq &&
                       irq < (child->pc_start + child->pc_length)) {
                           found = true;
                           break;
                   }
           }
           mtx_unlock_spin(&parent->pic_child_lock);
   
           if (found)
                   return (child->pc_filter(child->pc_filter_arg, irq));
   
           return (FILTER_STRAY);
   }
   
   /*
    *  interrupt controller dispatch function for interrupts. It should
    *  be called straight from the interrupt controller, when associated interrupt
    *  source is learned.
    */
   int
   intr_isrc_dispatch(struct intr_irqsrc *isrc, struct trapframe *tf)
   {
   
           KASSERT(isrc != NULL, ("%s: no source", __func__));
   
           isrc_increment_count(isrc);
   
   #ifdef INTR_SOLO
           if (isrc->isrc_filter != NULL) {
                   int error;
                   error = isrc->isrc_filter(isrc->isrc_arg, tf);
                   PIC_POST_FILTER(isrc->isrc_dev, isrc);
                   if (error == FILTER_HANDLED)
                           return (0);
           } else
   #endif
           if (isrc->isrc_event != NULL) {
                   if (intr_event_handle(isrc->isrc_event, tf) == 0)
                           return (0);
           }
   
           isrc_increment_straycount(isrc);
           return (EINVAL);
   }
   
   /*
    *  Alloc unique interrupt number (resource handle) for interrupt source.
    *
    *  There could be various strategies how to allocate free interrupt number
    *  (resource handle) for new interrupt source.
    *
    *  1. Handles are always allocated forward, so handles are not recycled
    *     immediately. However, if only one free handle left which is reused
    *     constantly...
    */
   static inline int
   isrc_alloc_irq(struct intr_irqsrc *isrc)
   {
           u_int maxirqs, irq;
   
           mtx_assert(&isrc_table_lock, MA_OWNED);
   
           maxirqs = nitems(irq_sources);
           if (irq_next_free >= maxirqs)
                   return (ENOSPC);
   
           for (irq = irq_next_free; irq < maxirqs; irq++) {
                   if (irq_sources[irq] == NULL)
                           goto found;
           }
           for (irq = 0; irq < irq_next_free; irq++) {
                   if (irq_sources[irq] == NULL)
                           goto found;
           }
   
           irq_next_free = maxirqs;
           return (ENOSPC);
   
   found:
           isrc->isrc_irq = irq;
           irq_sources[irq] = isrc;
   
           irq_next_free = irq + 1;
           if (irq_next_free >= maxirqs)
                   irq_next_free = 0;
           return (0);
   }
   
   /*
    *  Free unique interrupt number (resource handle) from interrupt source.
    */
   static inline int
   isrc_free_irq(struct intr_irqsrc *isrc)
   {
   
           mtx_assert(&isrc_table_lock, MA_OWNED);
   
           if (isrc->isrc_irq >= nitems(irq_sources))
                   return (EINVAL);
           if (irq_sources[isrc->isrc_irq] != isrc)
                   return (EINVAL);
   
           irq_sources[isrc->isrc_irq] = NULL;
           isrc->isrc_irq = INTR_IRQ_INVALID;      /* just to be safe */
           return (0);
   }
   
   /*
    *  Initialize interrupt source and register it into global interrupt table.
    */
   int
   intr_isrc_register(struct intr_irqsrc *isrc, device_t dev, u_int flags,
       const char *fmt, ...)
   {
           int error;
           va_list ap;
   
           bzero(isrc, sizeof(struct intr_irqsrc));
           isrc->isrc_dev = dev;
           isrc->isrc_irq = INTR_IRQ_INVALID;      /* just to be safe */
           isrc->isrc_flags = flags;
   
           va_start(ap, fmt);
           vsnprintf(isrc->isrc_name, INTR_ISRC_NAMELEN, fmt, ap);
           va_end(ap);
   
           mtx_lock(&isrc_table_lock);
           error = isrc_alloc_irq(isrc);
           if (error != 0) {
                   mtx_unlock(&isrc_table_lock);
                   return (error);
           }
           /*
            * Setup interrupt counters, but not for IPI sources. Those are setup
            * later and only for used ones (up to INTR_IPI_COUNT) to not exhaust
            * our counter pool.
            */
           if ((isrc->isrc_flags & INTR_ISRCF_IPI) == 0)
                   isrc_setup_counters(isrc);
           mtx_unlock(&isrc_table_lock);
           return (0);
   }
   
   /*
    *  Deregister interrupt source from global interrupt table.
    */
   int
   intr_isrc_deregister(struct intr_irqsrc *isrc)
   {
           int error;
   
           mtx_lock(&isrc_table_lock);
           if ((isrc->isrc_flags & INTR_ISRCF_IPI) == 0)
                   isrc_release_counters(isrc);
           error = isrc_free_irq(isrc);
           mtx_unlock(&isrc_table_lock);
           return (error);
   }
   
   #ifdef SMP
   /*
    *  A support function for a PIC to decide if provided ISRC should be inited
    *  on given cpu. The logic of INTR_ISRCF_BOUND flag and isrc_cpu member of
    *  struct intr_irqsrc is the following:
    *
    *     If INTR_ISRCF_BOUND is set, the ISRC should be inited only on cpus
    *     set in isrc_cpu. If not, the ISRC should be inited on every cpu and
    *     isrc_cpu is kept consistent with it. Thus isrc_cpu is always correct.
    */
   bool
   intr_isrc_init_on_cpu(struct intr_irqsrc *isrc, u_int cpu)
   {
   
           if (isrc->isrc_handlers == 0)
                   return (false);
           if ((isrc->isrc_flags & (INTR_ISRCF_PPI | INTR_ISRCF_IPI)) == 0)
                   return (false);
           if (isrc->isrc_flags & INTR_ISRCF_BOUND)
                   return (CPU_ISSET(cpu, &isrc->isrc_cpu));
   
           CPU_SET(cpu, &isrc->isrc_cpu);
           return (true);
   }
   #endif
   
   #ifdef INTR_SOLO
   /*
    *  Setup filter into interrupt source.
    */
   static int
   iscr_setup_filter(struct intr_irqsrc *isrc, const char *name,
       intr_irq_filter_t *filter, void *arg, void **cookiep)
   {
   
           if (filter == NULL)
                   return (EINVAL);
   
           mtx_lock(&isrc_table_lock);
           /*
            * Make sure that we do not mix the two ways
            * how we handle interrupt sources.
            */
           if (isrc->isrc_filter != NULL || isrc->isrc_event != NULL) {
                   mtx_unlock(&isrc_table_lock);
                   return (EBUSY);
           }
           isrc->isrc_filter = filter;
           isrc->isrc_arg = arg;
           isrc_update_name(isrc, name);
           mtx_unlock(&isrc_table_lock);
   
           *cookiep = isrc;
           return (0);
   }
   #endif
   
   /*
    *  Interrupt source pre_ithread method for MI interrupt framework.
    */
   static void
   intr_isrc_pre_ithread(void *arg)
   {
           struct intr_irqsrc *isrc = arg;
   
           PIC_PRE_ITHREAD(isrc->isrc_dev, isrc);
   }
   
   /*
    *  Interrupt source post_ithread method for MI interrupt framework.
    */
   static void
   intr_isrc_post_ithread(void *arg)
   {
           struct intr_irqsrc *isrc = arg;
   
           PIC_POST_ITHREAD(isrc->isrc_dev, isrc);
   }
   
   /*
    *  Interrupt source post_filter method for MI interrupt framework.
    */
   static void
   intr_isrc_post_filter(void *arg)
   {
           struct intr_irqsrc *isrc = arg;
   
           PIC_POST_FILTER(isrc->isrc_dev, isrc);
   }
   
   /*
    *  Interrupt source assign_cpu method for MI interrupt framework.
    */
   static int
   intr_isrc_assign_cpu(void *arg, int cpu)
   {
   #ifdef SMP
           struct intr_irqsrc *isrc = arg;
           int error;
   
           if (isrc->isrc_dev != intr_irq_root_dev)
                   return (EINVAL);
   
           mtx_lock(&isrc_table_lock);
           if (cpu == NOCPU) {
                   CPU_ZERO(&isrc->isrc_cpu);
                   isrc->isrc_flags &= ~INTR_ISRCF_BOUND;
           } else {
                   CPU_SETOF(cpu, &isrc->isrc_cpu);
                   isrc->isrc_flags |= INTR_ISRCF_BOUND;
           }
   
           /*
            * In NOCPU case, it's up to PIC to either leave ISRC on same CPU or
            * re-balance it to another CPU or enable it on more CPUs. However,
            * PIC is expected to change isrc_cpu appropriately to keep us well
            * informed if the call is successful.
            */
           if (irq_assign_cpu) {
                   error = PIC_BIND_INTR(isrc->isrc_dev, isrc);
                   if (error) {
                           CPU_ZERO(&isrc->isrc_cpu);
                           mtx_unlock(&isrc_table_lock);
                           return (error);
                   }
           }
           mtx_unlock(&isrc_table_lock);
           return (0);
   #else
           return (EOPNOTSUPP);
   #endif
   }
   
   /*
    *  Create interrupt event for interrupt source.
    */
   static int
   isrc_event_create(struct intr_irqsrc *isrc)
   {
           struct intr_event *ie;
           int error;
   
           error = intr_event_create(&ie, isrc, 0, isrc->isrc_irq,
               intr_isrc_pre_ithread, intr_isrc_post_ithread, intr_isrc_post_filter,
               intr_isrc_assign_cpu, "%s:", isrc->isrc_name);
           if (error)
                   return (error);
   
           mtx_lock(&isrc_table_lock);
           /*
            * Make sure that we do not mix the two ways
            * how we handle interrupt sources. Let contested event wins.
            */
   #ifdef INTR_SOLO
           if (isrc->isrc_filter != NULL || isrc->isrc_event != NULL) {
   #else
           if (isrc->isrc_event != NULL) {
   #endif
                   mtx_unlock(&isrc_table_lock);
                   intr_event_destroy(ie);
                   return (isrc->isrc_event != NULL ? EBUSY : 0);
           }
           isrc->isrc_event = ie;
           mtx_unlock(&isrc_table_lock);
   
           return (0);
   }
   #ifdef notyet
   /*
    *  Destroy interrupt event for interrupt source.
    */
   static void
   isrc_event_destroy(struct intr_irqsrc *isrc)
   {
           struct intr_event *ie;
   
           mtx_lock(&isrc_table_lock);
           ie = isrc->isrc_event;
           isrc->isrc_event = NULL;
           mtx_unlock(&isrc_table_lock);
   
           if (ie != NULL)
                   intr_event_destroy(ie);
   }
   #endif
   /*
    *  Add handler to interrupt source.
    */
   static int
   isrc_add_handler(struct intr_irqsrc *isrc, const char *name,
       driver_filter_t filter, driver_intr_t handler, void *arg,
       enum intr_type flags, void **cookiep)
   {
           int error;
   
           if (isrc->isrc_event == NULL) {
                   error = isrc_event_create(isrc);
                   if (error)
                           return (error);
           }
   
           error = intr_event_add_handler(isrc->isrc_event, name, filter, handler,
               arg, intr_priority(flags), flags, cookiep);
           if (error == 0) {
                   mtx_lock(&isrc_table_lock);
                   intrcnt_updatename(isrc);
                   mtx_unlock(&isrc_table_lock);
           }
   
           return (error);
   }
   
   /*
    *  Lookup interrupt controller locked.
    */
   static inline struct intr_pic *
   pic_lookup_locked(device_t dev, intptr_t xref)
   {
           struct intr_pic *pic;
   
           mtx_assert(&pic_list_lock, MA_OWNED);
   
           if (dev == NULL && xref == 0)
                   return (NULL);
   
           /* Note that pic->pic_dev is never NULL on registered PIC. */
           SLIST_FOREACH(pic, &pic_list, pic_next) {
                   if (dev == NULL) {
                           if (xref == pic->pic_xref)
                                   return (pic);
                   } else if (xref == 0 || pic->pic_xref == 0) {
                           if (dev == pic->pic_dev)
                                   return (pic);
                   } else if (xref == pic->pic_xref && dev == pic->pic_dev)
                                   return (pic);
           }
           return (NULL);
   }
   
   /*
    *  Lookup interrupt controller.
    */
   static struct intr_pic *
   pic_lookup(device_t dev, intptr_t xref)
   {
           struct intr_pic *pic;
   
           mtx_lock(&pic_list_lock);
           pic = pic_lookup_locked(dev, xref);
           mtx_unlock(&pic_list_lock);
           return (pic);
   }
   
   /*
    *  Create interrupt controller.
    */
   static struct intr_pic *
   pic_create(device_t dev, intptr_t xref)
   {
           struct intr_pic *pic;
   
           mtx_lock(&pic_list_lock);
           pic = pic_lookup_locked(dev, xref);
           if (pic != NULL) {
                   mtx_unlock(&pic_list_lock);
                   return (pic);
           }
           pic = malloc(sizeof(*pic), M_INTRNG, M_NOWAIT | M_ZERO);
           if (pic == NULL) {
                   mtx_unlock(&pic_list_lock);
                   return (NULL);
           }
           pic->pic_xref = xref;
           pic->pic_dev = dev;
           mtx_init(&pic->pic_child_lock, "pic child lock", NULL, MTX_SPIN);
           SLIST_INSERT_HEAD(&pic_list, pic, pic_next);
           mtx_unlock(&pic_list_lock);
   
           return (pic);
   }
   #ifdef notyet
   /*
    *  Destroy interrupt controller.
    */
   static void
   pic_destroy(device_t dev, intptr_t xref)
   {
           struct intr_pic *pic;
   
           mtx_lock(&pic_list_lock);
           pic = pic_lookup_locked(dev, xref);
           if (pic == NULL) {
                   mtx_unlock(&pic_list_lock);
                   return;
           }
           SLIST_REMOVE(&pic_list, pic, intr_pic, pic_next);
           mtx_unlock(&pic_list_lock);
   
           free(pic, M_INTRNG);
   }
   #endif
   /*
    *  Register interrupt controller.
    */
   struct intr_pic *
   intr_pic_register(device_t dev, intptr_t xref)
   {
           struct intr_pic *pic;
   
           if (dev == NULL)
                   return (NULL);
           pic = pic_create(dev, xref);
           if (pic == NULL)
                   return (NULL);
   
           pic->pic_flags |= FLAG_PIC;
   
           debugf("PIC %p registered for %s <dev %p, xref %x>\n", pic,
               device_get_nameunit(dev), dev, xref);
           return (pic);
   }
   
   /*
    *  Unregister interrupt controller.
    */
   int
   intr_pic_deregister(device_t dev, intptr_t xref)
   {
   
           panic("%s: not implemented", __func__);
   }
   
   /*
    *  Mark interrupt controller (itself) as a root one.
    *
    *  Note that only an interrupt controller can really know its position
    *  in interrupt controller's tree. So root PIC must claim itself as a root.
    *
    *  In FDT case, according to ePAPR approved version 1.1 from 08 April 2011,
    *  page 30:
    *    "The root of the interrupt tree is determined when traversal
    *     of the interrupt tree reaches an interrupt controller node without
    *     an interrupts property and thus no explicit interrupt parent."
    */
   int
   intr_pic_claim_root(device_t dev, intptr_t xref, intr_irq_filter_t *filter,
       void *arg, u_int ipicount)
   {
           struct intr_pic *pic;
   
           pic = pic_lookup(dev, xref);
           if (pic == NULL) {
                   device_printf(dev, "not registered\n");
                   return (EINVAL);
           }
   
           KASSERT((pic->pic_flags & FLAG_PIC) != 0,
               ("%s: Found a non-PIC controller: %s", __func__,
                device_get_name(pic->pic_dev)));
   
           if (filter == NULL) {
                   device_printf(dev, "filter missing\n");
                   return (EINVAL);
           }
   
           /*
            * Only one interrupt controllers could be on the root for now.
            * Note that we further suppose that there is not threaded interrupt
            * routine (handler) on the root. See intr_irq_handler().
            */
           if (intr_irq_root_dev != NULL) {
                   device_printf(dev, "another root already set\n");
                   return (EBUSY);
           }
   
           intr_irq_root_dev = dev;
           irq_root_filter = filter;
           irq_root_arg = arg;
           irq_root_ipicount = ipicount;
   
           debugf("irq root set to %s\n", device_get_nameunit(dev));
           return (0);
   }
   
   /*
    * Add a handler to manage a sub range of a parents interrupts.
    */
   struct intr_pic *
   intr_pic_add_handler(device_t parent, struct intr_pic *pic,
       intr_child_irq_filter_t *filter, void *arg, uintptr_t start,
       uintptr_t length)
   {
           struct intr_pic *parent_pic;
           struct intr_pic_child *newchild;
   #ifdef INVARIANTS
           struct intr_pic_child *child;
   #endif
   
           parent_pic = pic_lookup(parent, 0);
           if (parent_pic == NULL)
                   return (NULL);
   
           newchild = malloc(sizeof(*newchild), M_INTRNG, M_WAITOK | M_ZERO);
           newchild->pc_pic = pic;
           newchild->pc_filter = filter;
           newchild->pc_filter_arg = arg;
           newchild->pc_start = start;
           newchild->pc_length = length;
   
           mtx_lock_spin(&parent_pic->pic_child_lock);
   #ifdef INVARIANTS
           SLIST_FOREACH(child, &parent_pic->pic_children, pc_next) {
                   KASSERT(child->pc_pic != pic, ("%s: Adding a child PIC twice",
                       __func__));
           }
   #endif
           SLIST_INSERT_HEAD(&parent_pic->pic_children, newchild, pc_next);
           mtx_unlock_spin(&parent_pic->pic_child_lock);
   
           return (pic);
   }
   
   static int
   intr_resolve_irq(device_t dev, intptr_t xref, struct intr_map_data *data,
       struct intr_irqsrc **isrc)
   {
           struct intr_pic *pic;
           struct intr_map_data_msi *msi;
   
           if (data == NULL)
                   return (EINVAL);
   
           pic = pic_lookup(dev, xref);
           if (pic == NULL)
                   return (ESRCH);
   
           switch (data->type) {
           case INTR_MAP_DATA_MSI:
                   KASSERT((pic->pic_flags & FLAG_MSI) != 0,
                       ("%s: Found a non-MSI controller: %s", __func__,
                        device_get_name(pic->pic_dev)));
                   msi = (struct intr_map_data_msi *)data;
                   *isrc = msi->isrc;
                   return (0);
   
           default:
                   KASSERT((pic->pic_flags & FLAG_PIC) != 0,
                       ("%s: Found a non-PIC controller: %s", __func__,
                        device_get_name(pic->pic_dev)));
                   return (PIC_MAP_INTR(pic->pic_dev, data, isrc));
   
           }
   }
   
   int
   intr_activate_irq(device_t dev, struct resource *res)
   {
           device_t map_dev;
           intptr_t map_xref;
           struct intr_map_data *data;
           struct intr_irqsrc *isrc;
           u_int res_id;
           int error;
   
           KASSERT(rman_get_start(res) == rman_get_end(res),
               ("%s: more interrupts in resource", __func__));
   
           res_id = (u_int)rman_get_start(res);
           if (intr_map_get_isrc(res_id) != NULL)
                   panic("Attempt to double activation of resource id: %u\n",
                       res_id);
           intr_map_copy_map_data(res_id, &map_dev, &map_xref, &data);
           error = intr_resolve_irq(map_dev, map_xref, data, &isrc);
           if (error != 0) {
                   free(data, M_INTRNG);
                   /* XXX TODO DISCONECTED PICs */
                   /* if (error == EINVAL) return(0); */
                   return (error);
           }
           intr_map_set_isrc(res_id, isrc);
           rman_set_virtual(res, data);
           return (PIC_ACTIVATE_INTR(isrc->isrc_dev, isrc, res, data));
   }
   
   int
   intr_deactivate_irq(device_t dev, struct resource *res)
   {
           struct intr_map_data *data;
           struct intr_irqsrc *isrc;
           u_int res_id;
           int error;
   
           KASSERT(rman_get_start(res) == rman_get_end(res),
               ("%s: more interrupts in resource", __func__));
   
           res_id = (u_int)rman_get_start(res);
           isrc = intr_map_get_isrc(res_id);
           if (isrc == NULL)
                   panic("Attempt to deactivate non-active resource id: %u\n",
                       res_id);
   
           data = rman_get_virtual(res);
           error = PIC_DEACTIVATE_INTR(isrc->isrc_dev, isrc, res, data);
           intr_map_set_isrc(res_id, NULL);
           rman_set_virtual(res, NULL);
           free(data, M_INTRNG);
           return (error);
   }
   
   int
   intr_setup_irq(device_t dev, struct resource *res, driver_filter_t filt,
       driver_intr_t hand, void *arg, int flags, void **cookiep)
   {
           int error;
           struct intr_map_data *data;
           struct intr_irqsrc *isrc;
           const char *name;
           u_int res_id;
   
           KASSERT(rman_get_start(res) == rman_get_end(res),
               ("%s: more interrupts in resource", __func__));
   
           res_id = (u_int)rman_get_start(res);
           isrc = intr_map_get_isrc(res_id);
           if (isrc == NULL) {
                  /* XXX TODO DISCONECTED PICs */
                  return (EINVAL);
          }
  
          data = rman_get_virtual(res);
          name = device_get_nameunit(dev);
  
  #ifdef INTR_SOLO
          /*
           * Standard handling is done through MI interrupt framework. However,
           * some interrupts could request solely own special handling. This
           * non standard handling can be used for interrupt controllers without
           * handler (filter only), so in case that interrupt controllers are
           * chained, MI interrupt framework is called only in leaf controller.
           *
           * Note that root interrupt controller routine is served as well,
           * however in intr_irq_handler(), i.e. main system dispatch routine.
           */
          if (flags & INTR_SOLO && hand != NULL) {
                  debugf("irq %u cannot solo on %s\n", irq, name);
                  return (EINVAL);
          }
  
          if (flags & INTR_SOLO) {
                  error = iscr_setup_filter(isrc, name, (intr_irq_filter_t *)filt,
                      arg, cookiep);
                  debugf("irq %u setup filter error %d on %s\n", irq, error,
                      name);
          } else
  #endif
                  {
                  error = isrc_add_handler(isrc, name, filt, hand, arg, flags,
                      cookiep);
                  debugf("irq %u add handler error %d on %s\n", irq, error, name);
          }
          if (error != 0)
                  return (error);
  
          mtx_lock(&isrc_table_lock);
          error = PIC_SETUP_INTR(isrc->isrc_dev, isrc, res, data);
          if (error == 0) {
                  isrc->isrc_handlers++;
                  if (isrc->isrc_handlers == 1)
                          PIC_ENABLE_INTR(isrc->isrc_dev, isrc);
          }
          mtx_unlock(&isrc_table_lock);
          if (error != 0)
                  intr_event_remove_handler(*cookiep);
          return (error);
  }
  
  int
  intr_teardown_irq(device_t dev, struct resource *res, void *cookie)
  {
          int error;
          struct intr_map_data *data;
          struct intr_irqsrc *isrc;
          u_int res_id;
  
          KASSERT(rman_get_start(res) == rman_get_end(res),
              ("%s: more interrupts in resource", __func__));
  
          res_id = (u_int)rman_get_start(res);
          isrc = intr_map_get_isrc(res_id);
          if (isrc == NULL || isrc->isrc_handlers == 0)
                  return (EINVAL);
  
          data = rman_get_virtual(res);
  
  #ifdef INTR_SOLO
          if (isrc->isrc_filter != NULL) {
                  if (isrc != cookie)
                          return (EINVAL);
  
                  mtx_lock(&isrc_table_lock);
                  isrc->isrc_filter = NULL;
                  isrc->isrc_arg = NULL;
                  isrc->isrc_handlers = 0;
                  PIC_DISABLE_INTR(isrc->isrc_dev, isrc);
                  PIC_TEARDOWN_INTR(isrc->isrc_dev, isrc, res, data);
                  isrc_update_name(isrc, NULL);
                  mtx_unlock(&isrc_table_lock);
                  return (0);
          }
  #endif
          if (isrc != intr_handler_source(cookie))
                  return (EINVAL);
  
          error = intr_event_remove_handler(cookie);
          if (error == 0) {
                  mtx_lock(&isrc_table_lock);
                  isrc->isrc_handlers--;
                  if (isrc->isrc_handlers == 0)
                          PIC_DISABLE_INTR(isrc->isrc_dev, isrc);
                  PIC_TEARDOWN_INTR(isrc->isrc_dev, isrc, res, data);
                  intrcnt_updatename(isrc);
                  mtx_unlock(&isrc_table_lock);
          }
          return (error);
  }
  
  int
  intr_describe_irq(device_t dev, struct resource *res, void *cookie,
      const char *descr)
  {
          int error;
          struct intr_irqsrc *isrc;
          u_int res_id;
  
          KASSERT(rman_get_start(res) == rman_get_end(res),
              ("%s: more interrupts in resource", __func__));
  
          res_id = (u_int)rman_get_start(res);
          isrc = intr_map_get_isrc(res_id);
          if (isrc == NULL || isrc->isrc_handlers == 0)
                  return (EINVAL);
  #ifdef INTR_SOLO
          if (isrc->isrc_filter != NULL) {
                  if (isrc != cookie)
                          return (EINVAL);
  
                  mtx_lock(&isrc_table_lock);
                  isrc_update_name(isrc, descr);
                  mtx_unlock(&isrc_table_lock);
                  return (0);
          }
  #endif
          error = intr_event_describe_handler(isrc->isrc_event, cookie, descr);
          if (error == 0) {
                  mtx_lock(&isrc_table_lock);
                  intrcnt_updatename(isrc);
                  mtx_unlock(&isrc_table_lock);
          }
          return (error);
  }
  
  #ifdef SMP
  int
  intr_bind_irq(device_t dev, struct resource *res, int cpu)
  {
          struct intr_irqsrc *isrc;
          u_int res_id;
  
          KASSERT(rman_get_start(res) == rman_get_end(res),
              ("%s: more interrupts in resource", __func__));
  
          res_id = (u_int)rman_get_start(res);
          isrc = intr_map_get_isrc(res_id);
          if (isrc == NULL || isrc->isrc_handlers == 0)
                  return (EINVAL);
  #ifdef INTR_SOLO
          if (isrc->isrc_filter != NULL)
                  return (intr_isrc_assign_cpu(isrc, cpu));
  #endif
          return (intr_event_bind(isrc->isrc_event, cpu));
  }
  
  /*
   * Return the CPU that the next interrupt source should use.
   * For now just returns the next CPU according to round-robin.
   */
  u_int
  intr_irq_next_cpu(u_int last_cpu, cpuset_t *cpumask)
  {
  
          if (!irq_assign_cpu || mp_ncpus == 1)
                  return (PCPU_GET(cpuid));
  
          do {
                  last_cpu++;
                  if (last_cpu > mp_maxid)
                          last_cpu = 0;
          } while (!CPU_ISSET(last_cpu, cpumask));
          return (last_cpu);
  }
  
  /*
   *  Distribute all the interrupt sources among the available
   *  CPUs once the AP's have been launched.
   */
  static void
  intr_irq_shuffle(void *arg __unused)
  {
          struct intr_irqsrc *isrc;
          u_int i;
  
          if (mp_ncpus == 1)
                  return;
  
          mtx_lock(&isrc_table_lock);
          irq_assign_cpu = TRUE;
          for (i = 0; i < NIRQ; i++) {
                  isrc = irq_sources[i];
                  if (isrc == NULL || isrc->isrc_handlers == 0 ||
                      isrc->isrc_flags & (INTR_ISRCF_PPI | INTR_ISRCF_IPI))
                          continue;
  
                  if (isrc->isrc_event != NULL &&
                      isrc->isrc_flags & INTR_ISRCF_BOUND &&
                      isrc->isrc_event->ie_cpu != CPU_FFS(&isrc->isrc_cpu) - 1)
                          panic("%s: CPU inconsistency", __func__);
  
                  if ((isrc->isrc_flags & INTR_ISRCF_BOUND) == 0)
                          CPU_ZERO(&isrc->isrc_cpu); /* start again */
  
                  /*
                   * We are in wicked position here if the following call fails
                   * for bound ISRC. The best thing we can do is to clear
                   * isrc_cpu so inconsistency with ie_cpu will be detectable.
                   */
                  if (PIC_BIND_INTR(isrc->isrc_dev, isrc) != 0)
                          CPU_ZERO(&isrc->isrc_cpu);
          }
          mtx_unlock(&isrc_table_lock);
  }
  SYSINIT(intr_irq_shuffle, SI_SUB_SMP, SI_ORDER_SECOND, intr_irq_shuffle, NULL);
  
  #else
  u_int
  intr_irq_next_cpu(u_int current_cpu, cpuset_t *cpumask)
  {
  
          return (PCPU_GET(cpuid));
  }
  #endif
  
  /*
   * Allocate memory for new intr_map_data structure.
   * Initialize common fields.
   */
  struct intr_map_data *
  intr_alloc_map_data(enum intr_map_data_type type, size_t len, int flags)
  {
          struct intr_map_data *data;
  
          data = malloc(len, M_INTRNG, flags);
          data->type = type;
          data->len = len;
          return (data);
  }
  
  void intr_free_intr_map_data(struct intr_map_data *data)
  {
  
          free(data, M_INTRNG);
  }
  
  
  /*
   *  Register a MSI/MSI-X interrupt controller
   */
  int
  intr_msi_register(device_t dev, intptr_t xref)
  {
          struct intr_pic *pic;
  
          if (dev == NULL)
                  return (EINVAL);
          pic = pic_create(dev, xref);
          if (pic == NULL)
                  return (ENOMEM);
  
          pic->pic_flags |= FLAG_MSI;
  
          debugf("PIC %p registered for %s <dev %p, xref %jx>\n", pic,
              device_get_nameunit(dev), dev, (uintmax_t)xref);
          return (0);
  }
  
  int
  intr_alloc_msi(device_t pci, device_t child, intptr_t xref, int count,
      int maxcount, int *irqs)
  {
          struct intr_irqsrc **isrc;
          struct intr_pic *pic;
          device_t pdev;
          struct intr_map_data_msi *msi;
          int err, i;
  
          pic = pic_lookup(NULL, xref);
          if (pic == NULL)
                  return (ESRCH);
  
          KASSERT((pic->pic_flags & FLAG_MSI) != 0,
              ("%s: Found a non-MSI controller: %s", __func__,
               device_get_name(pic->pic_dev)));
  
          isrc = malloc(sizeof(*isrc) * count, M_INTRNG, M_WAITOK);
          err = MSI_ALLOC_MSI(pic->pic_dev, child, count, maxcount, &pdev, isrc);
          if (err != 0) {
                  free(isrc, M_INTRNG);
                  return (err);
          }
  
          for (i = 0; i < count; i++) {
                  msi = (struct intr_map_data_msi *)intr_alloc_map_data(
                      INTR_MAP_DATA_MSI, sizeof(*msi), M_WAITOK | M_ZERO);
                  msi-> isrc = isrc[i];
                  irqs[i] = intr_map_irq(pic->pic_dev, xref,
                      (struct intr_map_data *)msi);
  
          }
          free(isrc, M_INTRNG);
  
          return (err);
  }
  
  int
  intr_release_msi(device_t pci, device_t child, intptr_t xref, int count,
      int *irqs)
  {
          struct intr_irqsrc **isrc;
          struct intr_pic *pic;
          struct intr_map_data_msi *msi;
          int i, err;
  
          pic = pic_lookup(NULL, xref);
          if (pic == NULL)
                  return (ESRCH);
  
          KASSERT((pic->pic_flags & FLAG_MSI) != 0,
              ("%s: Found a non-MSI controller: %s", __func__,
               device_get_name(pic->pic_dev)));
  
          isrc = malloc(sizeof(*isrc) * count, M_INTRNG, M_WAITOK);
  
          for (i = 0; i < count; i++) {
                  msi = (struct intr_map_data_msi *)
                      intr_map_get_map_data(irqs[i]);
                  KASSERT(msi->hdr.type == INTR_MAP_DATA_MSI,
                      ("%s: irq %d map data is not MSI", __func__,
                      irqs[i]));
                  isrc[i] = msi->isrc;
          }
  
          err = MSI_RELEASE_MSI(pic->pic_dev, child, count, isrc);
  
          for (i = 0; i < count; i++) {
                  if (isrc[i] != NULL)
                          intr_unmap_irq(irqs[i]);
          }
  
          free(isrc, M_INTRNG);
          return (err);
  }
  
  int
  intr_alloc_msix(device_t pci, device_t child, intptr_t xref, int *irq)
  {
          struct intr_irqsrc *isrc;
          struct intr_pic *pic;
          device_t pdev;
          struct intr_map_data_msi *msi;
          int err;
  
          pic = pic_lookup(NULL, xref);
          if (pic == NULL)
                  return (ESRCH);
  
          KASSERT((pic->pic_flags & FLAG_MSI) != 0,
              ("%s: Found a non-MSI controller: %s", __func__,
               device_get_name(pic->pic_dev)));
  
  
          err = MSI_ALLOC_MSIX(pic->pic_dev, child, &pdev, &isrc);
          if (err != 0)
                  return (err);
  
          msi = (struct intr_map_data_msi *)intr_alloc_map_data(
                      INTR_MAP_DATA_MSI, sizeof(*msi), M_WAITOK | M_ZERO);
          msi->isrc = isrc;
          *irq = intr_map_irq(pic->pic_dev, xref, (struct intr_map_data *)msi);
          return (0);
  }
  
  int
  intr_release_msix(device_t pci, device_t child, intptr_t xref, int irq)
  {
          struct intr_irqsrc *isrc;
          struct intr_pic *pic;
          struct intr_map_data_msi *msi;
          int err;
  
          pic = pic_lookup(NULL, xref);
          if (pic == NULL)
                  return (ESRCH);
  
          KASSERT((pic->pic_flags & FLAG_MSI) != 0,
              ("%s: Found a non-MSI controller: %s", __func__,
               device_get_name(pic->pic_dev)));
  
          msi = (struct intr_map_data_msi *)
              intr_map_get_map_data(irq);
          KASSERT(msi->hdr.type == INTR_MAP_DATA_MSI,
              ("%s: irq %d map data is not MSI", __func__,
              irq));
          isrc = msi->isrc;
          if (isrc == NULL) {
                  intr_unmap_irq(irq);
                  return (EINVAL);
          }
  
          err = MSI_RELEASE_MSIX(pic->pic_dev, child, isrc);
          intr_unmap_irq(irq);
  
          return (err);
  }
  
  int
  intr_map_msi(device_t pci, device_t child, intptr_t xref, int irq,
      uint64_t *addr, uint32_t *data)
  {
          struct intr_irqsrc *isrc;
          struct intr_pic *pic;
          int err;
  
          pic = pic_lookup(NULL, xref);
          if (pic == NULL)
                  return (ESRCH);
  
          KASSERT((pic->pic_flags & FLAG_MSI) != 0,
              ("%s: Found a non-MSI controller: %s", __func__,
               device_get_name(pic->pic_dev)));
  
          isrc = intr_map_get_isrc(irq);
          if (isrc == NULL)
                  return (EINVAL);
  
          err = MSI_MAP_MSI(pic->pic_dev, child, isrc, addr, data);
          return (err);
  }
  
  
  void dosoftints(void);
  void
  dosoftints(void)
  {
  }
  
  #ifdef SMP
  /*
   *  Init interrupt controller on another CPU.
   */
  void
  intr_pic_init_secondary(void)
  {
  
          /*
           * QQQ: Only root PIC is aware of other CPUs ???
           */
          KASSERT(intr_irq_root_dev != NULL, ("%s: no root attached", __func__));
  
          //mtx_lock(&isrc_table_lock);
          PIC_INIT_SECONDARY(intr_irq_root_dev);
          //mtx_unlock(&isrc_table_lock);
  }
  #endif
  
  #ifdef DDB
  DB_SHOW_COMMAND(irqs, db_show_irqs)
  {
          u_int i, irqsum;
          u_long num;
          struct intr_irqsrc *isrc;
  
          for (irqsum = 0, i = 0; i < NIRQ; i++) {
                  isrc = irq_sources[i];
                  if (isrc == NULL)
                          continue;
  
                  num = isrc->isrc_count != NULL ? isrc->isrc_count[0] : 0;
                  db_printf("irq%-3u <%s>: cpu %02lx%s cnt %lu\n", i,
                      isrc->isrc_name, isrc->isrc_cpu.__bits[0],
                      isrc->isrc_flags & INTR_ISRCF_BOUND ? " (bound)" : "", num);
                  irqsum += num;
          }
          db_printf("irq total %u\n", irqsum);
  }
  #endif
  
  /*
   * Interrupt mapping table functions.
   *
   * Please, keep this part separately, it can be transformed to
   * extension of standard resources.
   */
  struct intr_map_entry
  {
          device_t                dev;
          intptr_t                xref;
          struct intr_map_data    *map_data;
          struct intr_irqsrc      *isrc;
          /* XXX TODO DISCONECTED PICs */
          /*int                   flags */
  };
  
  /* XXX Convert irq_map[] to dynamicaly expandable one. */
  static struct intr_map_entry *irq_map[2 * NIRQ];
  static int irq_map_count = nitems(irq_map);
  static int irq_map_first_free_idx;
  static struct mtx irq_map_lock;
  
  static struct intr_irqsrc *
  intr_map_get_isrc(u_int res_id)
  {
          struct intr_irqsrc *isrc;
  
          mtx_lock(&irq_map_lock);
          if ((res_id >= irq_map_count) || (irq_map[res_id] == NULL)) {
                  mtx_unlock(&irq_map_lock);
                  return (NULL);
          }
          isrc = irq_map[res_id]->isrc;
          mtx_unlock(&irq_map_lock);
          return (isrc);
  }
  
  static void
  intr_map_set_isrc(u_int res_id, struct intr_irqsrc *isrc)
  {
  
          mtx_lock(&irq_map_lock);
          if ((res_id >= irq_map_count) || (irq_map[res_id] == NULL)) {
                  mtx_unlock(&irq_map_lock);
                  return;
          }
          irq_map[res_id]->isrc = isrc;
          mtx_unlock(&irq_map_lock);
  }
  
  /*
   * Get a copy of intr_map_entry data
   */
  static struct intr_map_data *
  intr_map_get_map_data(u_int res_id)
  {
          struct intr_map_data *data;
  
          data = NULL;
          mtx_lock(&irq_map_lock);
          if (res_id >= irq_map_count || irq_map[res_id] == NULL)
                  panic("Attempt to copy invalid resource id: %u\n", res_id);
          data = irq_map[res_id]->map_data;
          mtx_unlock(&irq_map_lock);
  
          return (data);
  }
  
  /*
   * Get a copy of intr_map_entry data
   */
  static void
  intr_map_copy_map_data(u_int res_id, device_t *map_dev, intptr_t *map_xref,
      struct intr_map_data **data)
  {
          size_t len;
  
          len = 0;
          mtx_lock(&irq_map_lock);
          if (res_id >= irq_map_count || irq_map[res_id] == NULL)
                  panic("Attempt to copy invalid resource id: %u\n", res_id);
          if (irq_map[res_id]->map_data != NULL)
                  len = irq_map[res_id]->map_data->len;
          mtx_unlock(&irq_map_lock);
  
          if (len == 0)
                  *data = NULL;
          else
                  *data = malloc(len, M_INTRNG, M_WAITOK | M_ZERO);
          mtx_lock(&irq_map_lock);
          if (irq_map[res_id] == NULL)
                  panic("Attempt to copy invalid resource id: %u\n", res_id);
          if (len != 0) {
                  if (len != irq_map[res_id]->map_data->len)
                          panic("Resource id: %u has changed.\n", res_id);
                  memcpy(*data, irq_map[res_id]->map_data, len);
          }
          *map_dev = irq_map[res_id]->dev;
          *map_xref = irq_map[res_id]->xref;
          mtx_unlock(&irq_map_lock);
  }
  
  
  /*
   * Allocate and fill new entry in irq_map table.
   */
  u_int
  intr_map_irq(device_t dev, intptr_t xref, struct intr_map_data *data)
  {
          u_int i;
          struct intr_map_entry *entry;
  
          /* Prepare new entry first. */
          entry = malloc(sizeof(*entry), M_INTRNG, M_WAITOK | M_ZERO);
  
          entry->dev = dev;
          entry->xref = xref;
          entry->map_data = data;
          entry->isrc = NULL;
  
          mtx_lock(&irq_map_lock);
          for (i = irq_map_first_free_idx; i < irq_map_count; i++) {
                  if (irq_map[i] == NULL) {
                          irq_map[i] = entry;
                          irq_map_first_free_idx = i + 1;
                          mtx_unlock(&irq_map_lock);
                          return (i);
                  }
          }
          mtx_unlock(&irq_map_lock);
  
          /* XXX Expand irq_map table */
          panic("IRQ mapping table is full.");
  }
  
  /*
   * Remove and free mapping entry.
   */
  void
  intr_unmap_irq(u_int res_id)
  {
          struct intr_map_entry *entry;
  
          mtx_lock(&irq_map_lock);
          if ((res_id >= irq_map_count) || (irq_map[res_id] == NULL))
                  panic("Attempt to unmap invalid resource id: %u\n", res_id);
          entry = irq_map[res_id];
          irq_map[res_id] = NULL;
          irq_map_first_free_idx = res_id;
          mtx_unlock(&irq_map_lock);
          intr_free_intr_map_data(entry->map_data);
          free(entry, M_INTRNG);
  }
  
  /*
   * Clone mapping entry.
   */
  u_int
  intr_map_clone_irq(u_int old_res_id)
  {
          device_t map_dev;
          intptr_t map_xref;
          struct intr_map_data *data;
  
          intr_map_copy_map_data(old_res_id, &map_dev, &map_xref, &data);
          return (intr_map_irq(map_dev, map_xref, data));
  }
  
  static void
  intr_map_init(void *dummy __unused)
  {
  
          mtx_init(&irq_map_lock, "intr map table", NULL, MTX_DEF);
  }
  SYSINIT(intr_map_init, SI_SUB_INTR, SI_ORDER_FIRST, intr_map_init, NULL);

Cache object: 46066d8d983d6346bbbbf3e206092a14