/*	$NetBSD: intr.c,v 1.121 2019/03/01 02:33:55 macallan Exp $ */

/*
 * Copyright (c) 1992, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This software was developed by the Computer Systems Engineering group
 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
 * contributed to Berkeley.
 *
 * 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, Lawrence Berkeley Laboratory.
 *
 * 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. 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.
 *
 *	@(#)intr.c	8.3 (Berkeley) 11/11/93
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: intr.c,v 1.121 2019/03/01 02:33:55 macallan Exp $");

#include "opt_multiprocessor.h"
#include "opt_sparc_arch.h"
#include "sx.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/cpu.h>
#include <sys/intr.h>
#include <sys/atomic.h>

#include <uvm/uvm_extern.h>

#include <dev/cons.h>

#include <machine/ctlreg.h>
#include <machine/instr.h>
#include <machine/trap.h>
#include <machine/promlib.h>

#include <sparc/sparc/asm.h>
#include <sparc/sparc/cpuvar.h>

#if defined(MULTIPROCESSOR) && defined(DDB)
#include <machine/db_machdep.h>
#endif

#if NSX > 0
#include <sys/bus.h>
#include <sparc/dev/sxvar.h>
#endif

#if defined(MULTIPROCESSOR)
static int intr_biglock_wrapper(void *);

void *xcall_cookie;
#endif

extern kmutex_t xpmsg_mutex;

void	strayintr(struct clockframe *);
#ifdef DIAGNOSTIC
void	bogusintr(struct clockframe *);
#endif

/*
 * Stray interrupt handler.  Clear it if possible.
 * If not, and if we get 10 interrupts in 10 seconds, panic.
 * XXXSMP: We are holding the kernel lock at entry & exit.
 */
void
strayintr(struct clockframe *fp)
{
	static int straytime, nstray;
	char bits[64];
	int timesince;

#if defined(MULTIPROCESSOR)
	/*
	 * XXX
	 *
	 * Don't whine about zs interrupts on MP.  We sometimes get
	 * stray interrupts when polled kernel output on cpu>0 eats
	 * the interrupt and cpu0 sees it.
	 */
#define ZS_INTR_IPL	12
	if (fp->ipl == ZS_INTR_IPL)
		return;
#endif

	snprintb(bits, sizeof(bits), PSR_BITS, fp->psr);
	printf("stray interrupt cpu%d ipl 0x%x pc=0x%x npc=0x%x psr=%s\n",
	    cpu_number(), fp->ipl, fp->pc, fp->npc, bits);

	timesince = time_uptime - straytime;
	if (timesince <= 10) {
		if (++nstray > 10)
			panic("crazy interrupts");
	} else {
		straytime = time_uptime;
		nstray = 1;
	}
}


#ifdef DIAGNOSTIC
/*
 * Bogus interrupt for which neither hard nor soft interrupt bit in
 * the IPR was set.
 */
void
bogusintr(struct clockframe *fp)
{
	char bits[64];

#if defined(MULTIPROCESSOR)
	/*
	 * XXX as above.
	 */
	if (fp->ipl == ZS_INTR_IPL)
		return;
#endif

	snprintb(bits, sizeof(bits), PSR_BITS, fp->psr);
	printf("cpu%d: bogus interrupt ipl 0x%x pc=0x%x npc=0x%x psr=%s\n",
	    cpu_number(), fp->ipl, fp->pc, fp->npc, bits);
}
#endif /* DIAGNOSTIC */

/*
 * Get module ID of interrupt target.
 */
u_int
getitr(void)
{
#if defined(MULTIPROCESSOR)
	u_int v;

	if (!CPU_ISSUN4M || sparc_ncpus <= 1)
		return (0);

	v = *((u_int *)ICR_ITR);
	return (v + 8);
#else
	return (0);
#endif
}

/*
 * Set interrupt target.
 * Return previous value.
 */
u_int
setitr(u_int mid)
{
#if defined(MULTIPROCESSOR)
	u_int v;

	if (!CPU_ISSUN4M || sparc_ncpus <= 1)
		return (0);

	v = *((u_int *)ICR_ITR);
	*((u_int *)ICR_ITR) = CPU_MID2CPUNO(mid);
	return (v + 8);
#else
	return (0);
#endif
}

#if (defined(SUN4M) && !defined(MSIIEP)) || defined(SUN4D)
void	nmi_hard(void);
void	nmi_soft(struct trapframe *);

int	(*memerr_handler)(void);
int	(*sbuserr_handler)(void);
int	(*vmeerr_handler)(void);
int	(*moduleerr_handler)(void);

#if defined(MULTIPROCESSOR)
static volatile u_int	nmi_hard_wait = 0;
int			drop_into_rom_on_fatal = 1;
#endif

void
nmi_hard(void)
{
	/*
	 * A level 15 hard interrupt.
	 */
	int fatal = 0;
	uint32_t si;
	char bits[64];
	u_int afsr, afva;

	/* Tally */
	cpuinfo.ci_intrcnt[15].ev_count++;
	cpuinfo.ci_data.cpu_nintr++;

	afsr = afva = 0;
	if ((*cpuinfo.get_asyncflt)(&afsr, &afva) == 0) {
		snprintb(bits, sizeof(bits), AFSR_BITS, afsr);
		printf("Async registers (mid %d): afsr=%s; afva=0x%x%x\n",
			cpuinfo.mid, bits,
			(afsr & AFSR_AFA) >> AFSR_AFA_RSHIFT, afva);
	}

#if defined(MULTIPROCESSOR)
	/*
	 * Increase nmi_hard_wait.  If we aren't the master, loop while this
	 * variable is non-zero.  If we are the master, loop while this
	 * variable is less than the number of cpus.
	 */
	atomic_inc_uint(&nmi_hard_wait);

	if (cpuinfo.master == 0) {
		while (nmi_hard_wait)
			;
		return;
	} else {
		int n = 100000;

		while (nmi_hard_wait < sparc_ncpus) {
			DELAY(1);
			if (n-- > 0)
				continue;
			printf("nmi_hard: SMP botch.\n");
			break;
		}
	}
#endif

	/*
	 * Examine pending system interrupts.
	 */
	si = *((uint32_t *)ICR_SI_PEND);
	snprintb(bits, sizeof(bits), SINTR_BITS, si);
	printf("cpu%d: NMI: system interrupts: %s\n", cpu_number(), bits);

#if NSX > 0
	sx_dump();
#endif

	if ((si & SINTR_M) != 0) {
		/* ECC memory error */
		if (memerr_handler != NULL)
			fatal |= (*memerr_handler)();
	}
	if ((si & SINTR_I) != 0) {
		/* MBus/SBus async error */
		if (sbuserr_handler != NULL)
			fatal |= (*sbuserr_handler)();
	}
	if ((si & SINTR_V) != 0) {
		/* VME async error */
		if (vmeerr_handler != NULL)
			fatal |= (*vmeerr_handler)();
	}
	if ((si & SINTR_ME) != 0) {
		/* Module async error */
		if (moduleerr_handler != NULL)
			fatal |= (*moduleerr_handler)();
	}

#if defined(MULTIPROCESSOR)
	/*
	 * Tell everyone else we've finished dealing with the hard NMI.
	 */
	nmi_hard_wait = 0;
	if (fatal && drop_into_rom_on_fatal) {
		prom_abort();
		return;
	}
#endif

	if (fatal)
		panic("nmi");
}

/*
 * Non-maskable soft interrupt level 15 handler
 */
void
nmi_soft(struct trapframe *tf)
{

	/* Tally */
	cpuinfo.ci_sintrcnt[15].ev_count++;
	cpuinfo.ci_data.cpu_nintr++;

	if (cpuinfo.mailbox) {
		/* Check PROM messages */
		uint8_t msg = *(uint8_t *)cpuinfo.mailbox;
		switch (msg) {
		case OPENPROM_MBX_STOP:
		case OPENPROM_MBX_WD:
			/* In case there's an xcall in progress (unlikely) */
			spl0();
#ifdef MULTIPROCESSOR
			cpu_ready_mask &= ~(1 << cpu_number());
#endif
			prom_cpustop(0);
			break;
		case OPENPROM_MBX_ABORT:
		case OPENPROM_MBX_BPT:
			prom_cpuidle(0);
			/*
			 * We emerge here after someone does a
			 * prom_resumecpu(ournode).
			 */
			return;
		default:
			break;
		}
	}

#if defined(MULTIPROCESSOR)
	switch (cpuinfo.msg_lev15.tag) {
	case XPMSG15_PAUSECPU:
		/* XXX - assumes DDB is the only user of mp_pause_cpu() */
		cpuinfo.flags |= CPUFLG_PAUSED;
#if defined(DDB)
		/* trap(T_DBPAUSE) */
		__asm("ta 0x8b");
#else
		while (cpuinfo.flags & CPUFLG_PAUSED)
			/* spin */;
#endif /* DDB */
	}
	cpuinfo.msg_lev15.tag = 0;
#endif /* MULTIPROCESSOR */
}

#if defined(MULTIPROCESSOR)
/*
 * Respond to an xcall() request from another CPU.
 *
 * This is also called directly from xcall() if we notice an
 * incoming message while we're waiting to grab the xpmsg_lock.
 * We pass the address of xcallintr() itself to indicate that
 * this is not a real interrupt.
 */
void
xcallintr(void *v)
{

	kpreempt_disable();

	/* Tally */
	if (v != xcallintr)
		cpuinfo.ci_sintrcnt[13].ev_count++;

	/*
	 * This happens when the remote CPU is slow at responding and the
	 * caller gave up, and has given up the mutex.
	 */
	if (mutex_owned(&xpmsg_mutex) == 0) {
		cpuinfo.ci_xpmsg_mutex_not_held.ev_count++;
#ifdef DEBUG
		printf("%s: cpu%d mutex not held\n", __func__, cpu_number());
#endif
		cpuinfo.msg.complete = 1;
		kpreempt_enable();
		return;
	}

	if (cpuinfo.msg.complete != 0) {
		cpuinfo.ci_xpmsg_bogus.ev_count++;
#ifdef DEBUG
		volatile struct xpmsg_func *p = &cpuinfo.msg.u.xpmsg_func;
		printf("%s: bogus message %08x %08x %08x %08x\n", __func__,
		    cpuinfo.msg.tag, (uint32_t)p->func, p->arg0, p->arg1);
#endif
		kpreempt_enable();
		return;
	}

	/* notyet - cpuinfo.msg.received = 1; */
	switch (cpuinfo.msg.tag) {
	case XPMSG_FUNC:
	    {
		volatile struct xpmsg_func *p = &cpuinfo.msg.u.xpmsg_func;

		if (p->func)
			(*p->func)(p->arg0, p->arg1, p->arg2);
		break;
	    }
	}
	cpuinfo.msg.tag = 0;
	cpuinfo.msg.complete = 1;

	kpreempt_enable();
}
#endif /* MULTIPROCESSOR */
#endif /* SUN4M || SUN4D */


#ifdef MSIIEP
/*
 * It's easier to make this separate so that not to further obscure
 * SUN4M case with more ifdefs.  There's no common functionality
 * anyway.
 */

#include <sparc/sparc/msiiepreg.h>

void	nmi_hard_msiiep(void);
void	nmi_soft_msiiep(void);


void
nmi_hard_msiiep(void)
{
	uint32_t si;
	char bits[128];
	int fatal = 0;

	si = mspcic_read_4(pcic_sys_ipr);
	snprintb(bits, sizeof(bits), MSIIEP_SYS_IPR_BITS, si);
	printf("NMI: system interrupts: %s\n", bits);
	       

	if (si & MSIIEP_SYS_IPR_MEM_FAULT) {
		uint32_t afsr, afar, mfsr, mfar;

		afar = *(volatile uint32_t *)MSIIEP_AFAR;
		afsr = *(volatile uint32_t *)MSIIEP_AFSR;

		mfar = *(volatile uint32_t *)MSIIEP_MFAR;
		mfsr = *(volatile uint32_t *)MSIIEP_MFSR;

		if (afsr & MSIIEP_AFSR_ERR) {
			snprintb(bits, sizeof(bits), MSIIEP_AFSR_BITS, afsr);
			printf("async fault: afsr=%s; afar=%08x\n", bits, afar);
		}

		if (mfsr & MSIIEP_MFSR_ERR) {
			snprintb(bits, sizeof(bits), MSIIEP_MFSR_BITS, mfsr);
			printf("mem fault: mfsr=%s; mfar=%08x\n", bits, mfar);
		}

		fatal = 0;
	}

	if (si & MSIIEP_SYS_IPR_SERR) {	/* XXX */
		printf("serr#\n");
		fatal = 0;
	}

	if (si & MSIIEP_SYS_IPR_DMA_ERR) {
		printf("dma: %08x\n",
		       mspcic_read_stream_4(pcic_iotlb_err_addr));
		fatal = 0;
	}

	if (si & MSIIEP_SYS_IPR_PIO_ERR) {
		printf("pio: addr=%08x, cmd=%x stat=%04x\n",
		       mspcic_read_stream_4(pcic_pio_err_addr),
		       mspcic_read_stream_1(pcic_pio_err_cmd),
		       mspcic_read_stream_2(pcic_stat));
		fatal = 0;
	}

	if (fatal)
		panic("nmi");

	/* Clear the NMI if it was PCIC related */
	mspcic_write_1(pcic_sys_ipr_clr, MSIIEP_SYS_IPR_CLR_ALL);
}


void
nmi_soft_msiiep(void)
{

	panic("soft nmi");
}

#endif /* MSIIEP */


/*
 * Level 15 interrupts are special, and not vectored here.
 * Only `prewired' interrupts appear here; boot-time configured devices
 * are attached via intr_establish() below.
 */
struct intrhand *intrhand[15] = {
	NULL,			/*  0 = error */
	NULL,			/*  1 = software level 1 + Sbus */
	NULL,	 		/*  2 = Sbus level 2 (4m: Sbus L1) */
	NULL,			/*  3 = SCSI + DMA + Sbus level 3 (4m: L2,lpt)*/
	NULL,			/*  4 = software level 4 (tty softint) (scsi) */
	NULL,			/*  5 = Ethernet + Sbus level 4 (4m: Sbus L3) */
	NULL,			/*  6 = software level 6 (not used) (4m: enet)*/
	NULL,			/*  7 = video + Sbus level 5 */
	NULL,			/*  8 = Sbus level 6 */
	NULL,			/*  9 = Sbus level 7 */
	NULL, 			/* 10 = counter 0 = clock */
	NULL,			/* 11 = floppy */
	NULL,			/* 12 = zs hardware interrupt */
	NULL,			/* 13 = audio chip */
	NULL, 			/* 14 = counter 1 = profiling timer */
};

/*
 * Soft interrupts use a separate set of handler chains.
 * This is necessary since soft interrupt handlers do not return a value
 * and therefore cannot be mixed with hardware interrupt handlers on a
 * shared handler chain.
 */
struct intrhand *sintrhand[15] = { NULL };

static void
ih_insert(struct intrhand **head, struct intrhand *ih)
{
	struct intrhand **p, *q;
	/*
	 * This is O(N^2) for long chains, but chains are never long
	 * and we do want to preserve order.
	 */
	for (p = head; (q = *p) != NULL; p = &q->ih_next)
		continue;
	*p = ih;
	ih->ih_next = NULL;
}

static void
ih_remove(struct intrhand **head, struct intrhand *ih)
{
	struct intrhand **p, *q;

	for (p = head; (q = *p) != ih; p = &q->ih_next)
		continue;
	if (q == NULL)
		panic("intr_remove: intrhand %p fun %p arg %p",
			ih, ih->ih_fun, ih->ih_arg);

	*p = q->ih_next;
	q->ih_next = NULL;
}

static int fastvec;		/* marks fast vectors (see below) */
extern int sparc_interrupt4m[];
extern int sparc_interrupt44c[];

#ifdef DIAGNOSTIC
static void
check_tv(int level)
{
	struct trapvec *tv;
	int displ;

	/* double check for legal hardware interrupt */
	tv = &trapbase[T_L1INT - 1 + level];
	displ = (CPU_ISSUN4M || CPU_ISSUN4D)
		? &sparc_interrupt4m[0] - &tv->tv_instr[1]
		: &sparc_interrupt44c[0] - &tv->tv_instr[1];

	/* has to be `mov level,%l3; ba _sparc_interrupt; rdpsr %l0' */
	if (tv->tv_instr[0] != I_MOVi(I_L3, level) ||
	    tv->tv_instr[1] != I_BA(0, displ) ||
	    tv->tv_instr[2] != I_RDPSR(I_L0))
		panic("intr_establish(%d)\n0x%x 0x%x 0x%x != 0x%x 0x%x 0x%x",
		    level,
		    tv->tv_instr[0], tv->tv_instr[1], tv->tv_instr[2],
		    I_MOVi(I_L3, level), I_BA(0, displ), I_RDPSR(I_L0));
}
#endif

/*
 * Wire a fast trap vector.  Only one such fast trap is legal for any
 * interrupt, and it must be a hardware interrupt.
 */
static void
inst_fasttrap(int level, void (*vec)(void))
{
	struct trapvec *tv;
	u_long hi22, lo10;
	int s;

	if (CPU_ISSUN4 || CPU_ISSUN4C) {
		/* Can't wire to softintr slots */
		if (level == 1 || level == 4 || level == 6)
			return;
	}

#ifdef DIAGNOSTIC
	check_tv(level);
#endif

	tv = &trapbase[T_L1INT - 1 + level];
	hi22 = ((u_long)vec) >> 10;
	lo10 = ((u_long)vec) & 0x3ff;
	s = splhigh();

	/* kernel text is write protected -- let us in for a moment */
	pmap_kprotect((vaddr_t)tv & -PAGE_SIZE, PAGE_SIZE,
	    VM_PROT_READ|VM_PROT_WRITE);
	cpuinfo.cache_flush_all();
	tv->tv_instr[0] = I_SETHI(I_L3, hi22);	/* sethi %hi(vec),%l3 */
	tv->tv_instr[1] = I_JMPLri(I_G0, I_L3, lo10);/* jmpl %l3+%lo(vec),%g0 */
	tv->tv_instr[2] = I_RDPSR(I_L0);	/* mov %psr, %l0 */
	pmap_kprotect((vaddr_t)tv & -PAGE_SIZE, PAGE_SIZE, VM_PROT_READ);
	cpuinfo.cache_flush_all();
	fastvec |= 1 << level;
	splx(s);
}

/*
 * Uninstall a fast trap handler.
 */
static void
uninst_fasttrap(int level)
{
	struct trapvec *tv;
	int displ;	/* suspenders, belt, and buttons too */
	int s;

	tv = &trapbase[T_L1INT - 1 + level];
	s = splhigh();
	displ = (CPU_ISSUN4M || CPU_ISSUN4D)
		? &sparc_interrupt4m[0] - &tv->tv_instr[1]
		: &sparc_interrupt44c[0] - &tv->tv_instr[1];

	/* kernel text is write protected -- let us in for a moment */
	pmap_kprotect((vaddr_t)tv & -PAGE_SIZE, PAGE_SIZE,
	    VM_PROT_READ|VM_PROT_WRITE);
	cpuinfo.cache_flush_all();
	tv->tv_instr[0] = I_MOVi(I_L3, level);
	tv->tv_instr[1] = I_BA(0, displ);
	tv->tv_instr[2] = I_RDPSR(I_L0);
	pmap_kprotect((vaddr_t)tv & -PAGE_SIZE, PAGE_SIZE, VM_PROT_READ);
	cpuinfo.cache_flush_all();
	fastvec &= ~(1 << level);
	splx(s);
}

/*
 * Attach an interrupt handler to the vector chain for the given level.
 * This is not possible if it has been taken away as a fast vector.
 */
void
intr_establish(int level, int classipl,
	       struct intrhand *ih, void (*vec)(void),
	       bool maybe_mpsafe)
{
	int s = splhigh();
#ifdef MULTIPROCESSOR
	bool mpsafe;
#endif /* MULTIPROCESSOR */
	if (classipl == 0)
		classipl = level;

#ifdef MULTIPROCESSOR
	mpsafe = (classipl != IPL_VM) || maybe_mpsafe;
#endif

#ifdef DIAGNOSTIC
	if (CPU_ISSUN4C) {
		/*
		 * Check reserved softintr slots on SUN4C only.
		 * No check for SUN4, as 4/300's have
		 * esp0 at level 4 and le0 at level 6.
		 */
		if (level == 1 || level == 4 || level == 6)
			panic("intr_establish: reserved softintr level");
	}
#endif

	/*
	 * If a `fast vector' is currently tied to this level, we must
	 * first undo that.
	 */
	if (fastvec & (1 << level)) {
		printf("intr_establish: untie fast vector at level %d\n",
		    level);
		uninst_fasttrap(level);
	} else if (vec != NULL &&
		   intrhand[level] == NULL && sintrhand[level] == NULL) {
		inst_fasttrap(level, vec);
	}

	/* A requested IPL cannot exceed its device class level */
	if (classipl < level)
		panic("intr_establish: class lvl (%d) < pil (%d)\n",
			classipl, level);

	/* pre-shift to PIL field in %psr */
	ih->ih_classipl = (classipl << 8) & PSR_PIL;

#ifdef MULTIPROCESSOR
	if (!mpsafe) {
		ih->ih_realfun = ih->ih_fun;
		ih->ih_realarg = ih->ih_arg;
		ih->ih_fun = intr_biglock_wrapper;
		ih->ih_arg = ih;
	}
#endif /* MULTIPROCESSOR */

	ih_insert(&intrhand[level], ih);
	splx(s);
}

void
intr_disestablish(int level, struct intrhand *ih)
{

	ih_remove(&intrhand[level], ih);
}

/*
 * This is a softintr cookie.  NB that sic_pilreq MUST be the
 * first element in the struct, because the softintr_schedule()
 * macro in intr.h casts cookies to int * to get it.  On a
 * sun4m, sic_pilreq is an actual processor interrupt level that
 * is passed to raise(), and on a sun4 or sun4c sic_pilreq is a
 * bit to set in the interrupt enable register with ienab_bis().
 */
struct softintr_cookie {
	int sic_pilreq;		/* CPU-specific bits; MUST be first! */
	int sic_pil;		/* Actual machine PIL that is used */
	struct intrhand sic_hand;
};

/*
 * softintr_init(): initialise the MI softintr system.
 */
void
sparc_softintr_init(void)
{

#if defined(MULTIPROCESSOR) && (defined(SUN4M) || defined(SUN4D))
	/* Establish a standard soft interrupt handler for cross calls */
	xcall_cookie = sparc_softintr_establish(13, xcallintr, NULL);
#endif
}

/*
 * softintr_establish(): MI interface.  establish a func(arg) as a
 * software interrupt.
 */
void *
sparc_softintr_establish(int level, void (*fun)(void *), void *arg)
{
	struct softintr_cookie *sic;
	struct intrhand *ih;
	int pilreq;
	int pil;
#ifdef MULTIPROCESSOR
	bool mpsafe = (level != IPL_VM);
#endif /* MULTIPROCESSOR */

	/*
	 * On a sun4m, the processor interrupt level is stored
	 * in the softintr cookie to be passed to raise().
	 *
	 * On a sun4 or sun4c the appropriate bit to set
	 * in the interrupt enable register is stored in
	 * the softintr cookie to be passed to ienab_bis().
	 */
	pil = pilreq = level;
	if (CPU_ISSUN4 || CPU_ISSUN4C) {
		/* Select the most suitable of three available softint levels */
		if (level >= 1 && level < 4) {
			pil = 1;
			pilreq = IE_L1;
		} else if (level >= 4 && level < 6) {
			pil = 4;
			pilreq = IE_L4;
		} else {
			pil = 6;
			pilreq = IE_L6;
		}
	}

	sic = malloc(sizeof(*sic), M_DEVBUF, 0);
	sic->sic_pil = pil;
	sic->sic_pilreq = pilreq;
	ih = &sic->sic_hand;
#ifdef MULTIPROCESSOR
	if (!mpsafe) {
		ih->ih_realfun = (int (*)(void *))fun;
		ih->ih_realarg = arg;
		ih->ih_fun = intr_biglock_wrapper;
		ih->ih_arg = ih;
	} else
#endif /* MULTIPROCESSOR */
	{
		ih->ih_fun = (int (*)(void *))fun;
		ih->ih_arg = arg;
	}

	/*
	 * Always run the handler at the requested level, which might
	 * be higher than the hardware can provide.
	 *
	 * pre-shift to PIL field in %psr
	 */
	ih->ih_classipl = (level << 8) & PSR_PIL;

	if (fastvec & (1 << pil)) {
		printf("softintr_establish: untie fast vector at level %d\n",
		    pil);
		uninst_fasttrap(level);
	}

	ih_insert(&sintrhand[pil], ih);
	return (void *)sic;
}

/*
 * softintr_disestablish(): MI interface.  disestablish the specified
 * software interrupt.
 */
void
sparc_softintr_disestablish(void *cookie)
{
	struct softintr_cookie *sic = cookie;

	ih_remove(&sintrhand[sic->sic_pil], &sic->sic_hand);
	free(cookie, M_DEVBUF);
}

#if 0
void
sparc_softintr_schedule(void *cookie)
{
	struct softintr_cookie *sic = cookie;
	if (CPU_ISSUN4M || CPU_ISSUN4D) {
#if defined(SUN4M) || defined(SUN4D)
		extern void raise(int,int);
		raise(0, sic->sic_pilreq);
#endif
	} else {
#if defined(SUN4) || defined(SUN4C)
		ienab_bis(sic->sic_pilreq);
#endif
	}
}
#endif

#ifdef MULTIPROCESSOR

/*
 * intr_biglock_wrapper: grab biglock and call a real interrupt handler.
 */

static int
intr_biglock_wrapper(void *vp)
{
	struct intrhand *ih = vp;
	int ret;

	KERNEL_LOCK(1, NULL);

	ret = (*ih->ih_realfun)(ih->ih_realarg);

	KERNEL_UNLOCK_ONE(NULL);

	return ret;
}
#endif /* MULTIPROCESSOR */

bool
cpu_intr_p(void)
{
	int idepth;

	kpreempt_disable();
	idepth = curcpu()->ci_idepth;
	kpreempt_enable();

	return idepth != 0;
}