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isa.c revision 1.28.2.13
      1        1.1      cgd /*-
      2   1.28.2.7  mycroft  * Copyright (c) 1993 Charles Hannum.
      3        1.1      cgd  * Copyright (c) 1991 The Regents of the University of California.
      4        1.1      cgd  * All rights reserved.
      5        1.1      cgd  *
      6        1.1      cgd  * This code is derived from software contributed to Berkeley by
      7        1.1      cgd  * William Jolitz.
      8        1.1      cgd  *
      9        1.1      cgd  * Redistribution and use in source and binary forms, with or without
     10        1.1      cgd  * modification, are permitted provided that the following conditions
     11        1.1      cgd  * are met:
     12        1.1      cgd  * 1. Redistributions of source code must retain the above copyright
     13        1.1      cgd  *    notice, this list of conditions and the following disclaimer.
     14        1.1      cgd  * 2. Redistributions in binary form must reproduce the above copyright
     15        1.1      cgd  *    notice, this list of conditions and the following disclaimer in the
     16        1.1      cgd  *    documentation and/or other materials provided with the distribution.
     17        1.1      cgd  * 3. All advertising materials mentioning features or use of this software
     18        1.1      cgd  *    must display the following acknowledgement:
     19        1.1      cgd  *	This product includes software developed by the University of
     20        1.1      cgd  *	California, Berkeley and its contributors.
     21        1.1      cgd  * 4. Neither the name of the University nor the names of its contributors
     22        1.1      cgd  *    may be used to endorse or promote products derived from this software
     23        1.1      cgd  *    without specific prior written permission.
     24        1.1      cgd  *
     25        1.1      cgd  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     26        1.1      cgd  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     27        1.1      cgd  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     28        1.1      cgd  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     29        1.1      cgd  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     30        1.1      cgd  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     31        1.1      cgd  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     32        1.1      cgd  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     33        1.1      cgd  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     34        1.1      cgd  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     35        1.1      cgd  * SUCH DAMAGE.
     36        1.1      cgd  *
     37       1.13      cgd  *	from: @(#)isa.c	7.2 (Berkeley) 5/13/91
     38  1.28.2.13  mycroft  *	$Id: isa.c,v 1.28.2.13 1993/10/16 04:00:59 mycroft Exp $
     39        1.1      cgd  */
     40        1.1      cgd 
     41        1.1      cgd /*
     42        1.1      cgd  * code to manage AT bus
     43        1.1      cgd  */
     44        1.1      cgd 
     45        1.1      cgd #include "param.h"
     46        1.1      cgd #include "systm.h"
     47        1.1      cgd #include "conf.h"
     48        1.1      cgd #include "file.h"
     49        1.1      cgd #include "syslog.h"
     50   1.28.2.2  mycroft #include "machine/cpu.h"
     51   1.28.2.6  mycroft #include "machine/pio.h"
     52   1.28.2.1  mycroft #include "sys/device.h"
     53        1.1      cgd #include "vm/vm.h"
     54        1.1      cgd #include "i386/isa/isa.h"
     55   1.28.2.1  mycroft #include "i386/isa/isavar.h"
     56        1.1      cgd #include "i386/isa/icu.h"
     57       1.16  mycroft #include "i386/isa/timerreg.h"
     58       1.28   brezak #include "i386/isa/spkr_reg.h"
     59       1.14  deraadt 
     60   1.28.2.1  mycroft isa_type isa_bustype;				/* type of bus */
     61        1.1      cgd 
     62   1.28.2.1  mycroft static int isaprobe __P((struct device *, struct cfdata *, void *));
     63   1.28.2.2  mycroft static void isaattach __P((struct device *, struct device *, void *));
     64   1.28.2.2  mycroft static int isasubmatch __P((struct device *, struct cfdata *, void *));
     65   1.28.2.1  mycroft 
     66   1.28.2.1  mycroft struct cfdriver isacd =
     67   1.28.2.2  mycroft     { NULL, "isa", isaprobe, isaattach, DV_DULL, sizeof(struct isa_softc) };
     68   1.28.2.1  mycroft 
     69   1.28.2.9  mycroft static void isa_defaultirq __P((void));
     70   1.28.2.2  mycroft static int isaprint __P((void *, char *));
     71   1.28.2.9  mycroft static void isa_flushintrs __P((void));
     72  1.28.2.12  mycroft static void isa_intrmaskwickedness __P((void));
     73   1.28.2.2  mycroft 
     74   1.28.2.2  mycroft /*
     75   1.28.2.2  mycroft  * We think there might be an ISA bus here.  Check it out.
     76   1.28.2.2  mycroft  */
     77   1.28.2.2  mycroft static int
     78   1.28.2.1  mycroft isaprobe(parent, cf, aux)
     79   1.28.2.1  mycroft 	struct device *parent;
     80   1.28.2.1  mycroft 	struct cfdata *cf;
     81   1.28.2.1  mycroft 	void *aux;
     82   1.28.2.1  mycroft {
     83   1.28.2.1  mycroft 
     84   1.28.2.1  mycroft 	/* XXX should do a real probe */
     85   1.28.2.1  mycroft 	isa_bustype = BUS_ISA;
     86   1.28.2.1  mycroft 	return 1;
     87   1.28.2.1  mycroft }
     88   1.28.2.1  mycroft 
     89   1.28.2.2  mycroft /*
     90   1.28.2.2  mycroft  * Probe succeeded, someone called config_attach.  Now we have to
     91   1.28.2.2  mycroft  * probe the ISA bus itself in our turn.
     92   1.28.2.2  mycroft  */
     93   1.28.2.2  mycroft static void
     94   1.28.2.2  mycroft isaattach(parent, self, aux)
     95   1.28.2.2  mycroft 	struct device *parent, *self;
     96   1.28.2.2  mycroft 	void *aux;
     97   1.28.2.2  mycroft {
     98   1.28.2.2  mycroft 
     99   1.28.2.7  mycroft 	/* XXX should print ISA/EISA & bus clock frequency and anything else
    100   1.28.2.2  mycroft 	   we can figure out? */
    101   1.28.2.2  mycroft 	printf("\n");
    102   1.28.2.2  mycroft 
    103   1.28.2.2  mycroft 	isa_defaultirq();
    104   1.28.2.9  mycroft 	disable_intr();
    105   1.28.2.2  mycroft 	intr_enable(IRQ_SLAVE);
    106   1.28.2.2  mycroft 
    107   1.28.2.2  mycroft 	/* Iterate ``isasubmatch'' over all devices configured here. */
    108   1.28.2.2  mycroft 	(void)config_search(isasubmatch, self, (void *)NULL);
    109   1.28.2.2  mycroft 
    110  1.28.2.12  mycroft 	isa_intrmaskwickedness();
    111   1.28.2.9  mycroft 
    112   1.28.2.9  mycroft 	isa_flushintrs();
    113   1.28.2.9  mycroft 	enable_intr();
    114   1.28.2.2  mycroft 	splnone();
    115   1.28.2.2  mycroft }
    116   1.28.2.2  mycroft 
    117   1.28.2.2  mycroft /*
    118   1.28.2.2  mycroft  * isaattach (above) iterates this function over all the sub-devices that
    119   1.28.2.2  mycroft  * were configured at the ``isa'' device.  Our job is to provide defaults
    120   1.28.2.2  mycroft  * and do some internal/external representation conversion (some of which
    121   1.28.2.2  mycroft  * is scheduled to get cleaned up later), then call the device's probe
    122   1.28.2.2  mycroft  * function.  If this says the device is there, we try to reserve ISA
    123   1.28.2.2  mycroft  * bus memory and ports for the device, and attach it.
    124   1.28.2.2  mycroft  *
    125   1.28.2.2  mycroft  * Note that we always return 0, but our ultimate caller (isaattach)
    126   1.28.2.2  mycroft  * does not care that we never `match' anything.  (In fact, our return
    127   1.28.2.2  mycroft  * value is entirely irrelevant; this function is run entirely for its
    128   1.28.2.2  mycroft  * side effects.)
    129   1.28.2.2  mycroft  */
    130   1.28.2.1  mycroft static int
    131   1.28.2.2  mycroft isasubmatch(isa, cf, aux)
    132   1.28.2.2  mycroft 	struct device *isa;
    133   1.28.2.1  mycroft 	struct cfdata *cf;
    134   1.28.2.1  mycroft 	void *aux;
    135   1.28.2.1  mycroft {
    136   1.28.2.2  mycroft 	struct isa_attach_args ia;
    137   1.28.2.1  mycroft 
    138   1.28.2.1  mycroft #ifdef DIAGNOSTIC
    139   1.28.2.2  mycroft 	if (cf->cf_driver->cd_match == NULL) {
    140   1.28.2.2  mycroft 		/* we really ought to add printf formats to panic(). */
    141   1.28.2.1  mycroft 		printf("isasubmatch: no match function for `%s' device\n",
    142   1.28.2.1  mycroft 			cf->cf_driver->cd_name);
    143   1.28.2.1  mycroft 		panic("isasubmatch: no match function\n");
    144   1.28.2.1  mycroft 	}
    145   1.28.2.1  mycroft #endif
    146   1.28.2.1  mycroft 
    147  1.28.2.12  mycroft 	/* Init the info needed in the device probe and attach routines. */
    148   1.28.2.2  mycroft 	ia.ia_iobase = cf->cf_iobase;
    149   1.28.2.2  mycroft 	ia.ia_iosize = cf->cf_iosize;
    150   1.28.2.2  mycroft 	if (cf->cf_irq == -1)
    151   1.28.2.2  mycroft 		ia.ia_irq = IRQUNK;
    152   1.28.2.2  mycroft 	else
    153   1.28.2.2  mycroft 		ia.ia_irq = 1 << cf->cf_irq;
    154   1.28.2.2  mycroft 	ia.ia_drq = cf->cf_drq;
    155   1.28.2.2  mycroft 	ia.ia_maddr = (caddr_t)cf->cf_maddr;
    156   1.28.2.2  mycroft 	ia.ia_msize = cf->cf_msize;
    157   1.28.2.1  mycroft 
    158   1.28.2.2  mycroft 	/* If driver says it's not there, believe it. */
    159   1.28.2.2  mycroft 	if (!cf->cf_driver->cd_match(isa, cf, &ia))
    160   1.28.2.1  mycroft 		return 0;
    161   1.28.2.1  mycroft 
    162  1.28.2.12  mycroft 	/* Check for port or shared memory conflicts. */
    163  1.28.2.12  mycroft 	if (ia.ia_iosize && !isa_portcheck(ia.ia_iobase, ia.ia_iosize))
    164  1.28.2.12  mycroft 		return 0;
    165  1.28.2.12  mycroft 	if (ia.ia_msize && !isa_memcheck(ia.ia_maddr, ia.ia_msize))
    166  1.28.2.12  mycroft 		return 0;
    167  1.28.2.12  mycroft 
    168  1.28.2.12  mycroft 	/* Reserve I/O ports and/or shared memory. */
    169  1.28.2.12  mycroft 	if (ia.ia_iosize)
    170  1.28.2.11  mycroft 		isa_portalloc(ia.ia_iobase, ia.ia_iosize);
    171  1.28.2.12  mycroft 	if (ia.ia_msize)
    172  1.28.2.12  mycroft 		isa_memalloc(ia.ia_maddr, ia.ia_msize);
    173  1.28.2.12  mycroft 
    174  1.28.2.12  mycroft 	/* Configure device. */
    175  1.28.2.12  mycroft 	config_attach(isa, cf, &ia, isaprint);
    176   1.28.2.1  mycroft 
    177   1.28.2.2  mycroft 	return 0;
    178   1.28.2.1  mycroft }
    179   1.28.2.1  mycroft 
    180   1.28.2.2  mycroft /*
    181   1.28.2.2  mycroft  * Called indirectly via config_attach (see above).  Config has already
    182   1.28.2.2  mycroft  * printed, e.g., "wdc0 at isa0".  We can ignore our ``isaname'' arg
    183   1.28.2.2  mycroft  * (it is always NULL, by definition) and just extend the line with
    184   1.28.2.2  mycroft  * the standard info (port(s), irq, drq, and iomem).
    185   1.28.2.2  mycroft  */
    186   1.28.2.2  mycroft static int
    187   1.28.2.1  mycroft isaprint(aux, isaname)
    188   1.28.2.1  mycroft 	void *aux;
    189   1.28.2.1  mycroft 	char *isaname;
    190   1.28.2.1  mycroft {
    191   1.28.2.1  mycroft 	struct isa_attach_args *ia = aux;
    192   1.28.2.1  mycroft 
    193   1.28.2.1  mycroft 	if (ia->ia_iosize)
    194   1.28.2.1  mycroft 		printf(" port 0x%x", ia->ia_iobase);
    195   1.28.2.1  mycroft 	if (ia->ia_iosize > 1)
    196   1.28.2.1  mycroft 		printf("-0x%x", ia->ia_iobase + ia->ia_iosize - 1);
    197  1.28.2.12  mycroft 	if (ia->ia_msize)
    198  1.28.2.12  mycroft 		printf(" iomem 0x%x", ia->ia_maddr);
    199  1.28.2.12  mycroft 	if (ia->ia_msize > 1)
    200  1.28.2.12  mycroft 		printf("-0x%x", ia->ia_maddr + ia->ia_msize - 1);
    201   1.28.2.3  mycroft #ifdef DIAGNOSTIC
    202   1.28.2.3  mycroft 	if (ia->ia_irq == IRQUNK)
    203   1.28.2.4  mycroft 		printf(" THIS IS A BUG ->");
    204   1.28.2.3  mycroft #endif
    205   1.28.2.3  mycroft 	if (ia->ia_irq != IRQNONE)
    206   1.28.2.1  mycroft 		printf(" irq %d", ffs(ia->ia_irq) - 1);
    207   1.28.2.1  mycroft 	if (ia->ia_drq != DRQUNK)
    208   1.28.2.1  mycroft 		printf(" drq %d", ia->ia_drq);
    209   1.28.2.7  mycroft 	/* XXXX print flags */
    210   1.28.2.2  mycroft 	return QUIET;	/* actually, our return value is irrelevant. */
    211        1.1      cgd }
    212        1.1      cgd 
    213  1.28.2.13  mycroft /*
    214  1.28.2.12  mycroft int isa_portcheck __P((u_int, u_int));
    215  1.28.2.12  mycroft int isa_memcheck __P((u_int, u_int));
    216  1.28.2.12  mycroft void isa_portalloc __P((u_int, u_int));
    217  1.28.2.12  mycroft void isa_memalloc __P((u_int, u_int));
    218  1.28.2.13  mycroft */
    219  1.28.2.12  mycroft 
    220  1.28.2.12  mycroft int	intrmask[NIRQ];
    221  1.28.2.12  mycroft struct	intrhand *intrhand[NIRQ];
    222  1.28.2.12  mycroft 
    223  1.28.2.12  mycroft /*
    224  1.28.2.12  mycroft  * Register an interrupt handler.
    225  1.28.2.12  mycroft  */
    226  1.28.2.12  mycroft void
    227  1.28.2.12  mycroft intr_establish(intr, handler, class)
    228  1.28.2.12  mycroft 	int intr;
    229  1.28.2.12  mycroft 	struct intrhand *handler;
    230  1.28.2.12  mycroft 	enum devclass class;
    231  1.28.2.12  mycroft {
    232  1.28.2.12  mycroft 	int irqnum = ffs(intr) - 1;
    233  1.28.2.12  mycroft 
    234  1.28.2.12  mycroft #ifdef DIAGNOSTIC
    235  1.28.2.12  mycroft 	if (intr == IRQUNK || intr == IRQNONE ||
    236  1.28.2.12  mycroft 	    (intr &~ (1 << irqnum)) != IRQNONE)
    237  1.28.2.12  mycroft 		panic("intr_establish: weird irq");
    238  1.28.2.12  mycroft #endif
    239  1.28.2.12  mycroft 
    240  1.28.2.12  mycroft 	switch (class) {
    241  1.28.2.12  mycroft 	    case DV_DULL:
    242  1.28.2.12  mycroft 		break;
    243  1.28.2.12  mycroft 	    case DV_DISK:
    244  1.28.2.12  mycroft 	    case DV_TAPE:
    245  1.28.2.12  mycroft 		biomask |= intr;
    246  1.28.2.12  mycroft 		break;
    247  1.28.2.12  mycroft 	    case DV_IFNET:
    248  1.28.2.12  mycroft 		netmask |= intr;
    249  1.28.2.12  mycroft 		break;
    250  1.28.2.12  mycroft 	    case DV_TTY:
    251  1.28.2.12  mycroft 		ttymask |= intr;
    252  1.28.2.12  mycroft 		break;
    253  1.28.2.12  mycroft 	    case DV_CPU:
    254  1.28.2.12  mycroft 	    default:
    255  1.28.2.12  mycroft 		panic("intrhand: weird devclass");
    256  1.28.2.12  mycroft 	}
    257  1.28.2.13  mycroft 
    258  1.28.2.13  mycroft 	handler->ih_count = 0;
    259  1.28.2.13  mycroft 	handler->ih_next = intrhand[irqnum];
    260  1.28.2.13  mycroft 	intrhand[irqnum] = handler;
    261  1.28.2.13  mycroft 
    262  1.28.2.13  mycroft 	intr_enable(intr);
    263  1.28.2.12  mycroft }
    264  1.28.2.12  mycroft 
    265  1.28.2.12  mycroft /*
    266  1.28.2.12  mycroft  * Set up the masks for each interrupt handler based on the information
    267  1.28.2.12  mycroft  * recorded by intr_establish().
    268  1.28.2.12  mycroft  */
    269  1.28.2.12  mycroft static void
    270  1.28.2.12  mycroft isa_intrmaskwickedness()
    271  1.28.2.12  mycroft {
    272  1.28.2.12  mycroft 	int irq, mask;
    273  1.28.2.12  mycroft 
    274  1.28.2.12  mycroft 	for (irq = 0; irq < NIRQ; irq++) {
    275  1.28.2.12  mycroft 		mask = (1 << irq) | astmask;
    276  1.28.2.12  mycroft 		if (biomask & (1 << irq))
    277  1.28.2.12  mycroft 			mask |= biomask;
    278  1.28.2.12  mycroft 		if (ttymask & (1 << irq))
    279  1.28.2.12  mycroft 			mask |= ttymask;
    280  1.28.2.12  mycroft 		if (netmask & (1 << irq))
    281  1.28.2.12  mycroft 			mask |= netmask;
    282  1.28.2.12  mycroft 		intrmask[irq] = mask;
    283  1.28.2.12  mycroft 	}
    284  1.28.2.12  mycroft 
    285  1.28.2.12  mycroft 	impmask = netmask | ttymask;
    286  1.28.2.12  mycroft 	printf("biomask %x ttymask %x netmask %x impmask %x astmask %s\n",
    287  1.28.2.12  mycroft 	       biomask, ttymask, netmask, impmask, astmask);
    288  1.28.2.12  mycroft }
    289        1.1      cgd 
    290        1.1      cgd #define	IDTVEC(name)	__CONCAT(X,name)
    291        1.1      cgd /* default interrupt vector table entries */
    292   1.28.2.7  mycroft extern	*IDTVEC(intr)[NIRQ];
    293        1.1      cgd /* out of range default interrupt vector gate entry */
    294   1.28.2.7  mycroft extern	IDTVEC(stray);
    295       1.15      cgd 
    296        1.1      cgd /*
    297   1.28.2.1  mycroft  * Fill in default interrupt table, and mask all interrupts.
    298        1.1      cgd  */
    299   1.28.2.9  mycroft static void
    300   1.28.2.1  mycroft isa_defaultirq()
    301   1.28.2.1  mycroft {
    302        1.1      cgd 	int i;
    303        1.1      cgd 
    304        1.1      cgd 	/* icu vectors */
    305   1.28.2.1  mycroft 	for (i = ICU_OFFSET; i < ICU_OFFSET + ICU_LEN ; i++)
    306   1.28.2.7  mycroft 		setidt(i, IDTVEC(intr)[i],  SDT_SYS386IGT, SEL_KPL);
    307       1.15      cgd 
    308        1.1      cgd 	/* out of range vectors */
    309   1.28.2.1  mycroft 	for (; i < NIDT; i++)
    310   1.28.2.7  mycroft 		setidt(i, &IDTVEC(stray), SDT_SYS386IGT, SEL_KPL);
    311        1.1      cgd 
    312        1.1      cgd 	/* initialize 8259's */
    313        1.1      cgd 	outb(IO_ICU1, 0x11);		/* reset; program device, four bytes */
    314   1.28.2.1  mycroft 	outb(IO_ICU1+1, ICU_OFFSET);	/* starting at this vector index */
    315   1.28.2.1  mycroft 	outb(IO_ICU1+1, IRQ_SLAVE);
    316       1.15      cgd #ifdef AUTO_EOI_1
    317       1.15      cgd 	outb(IO_ICU1+1, 2 | 1);		/* auto EOI, 8086 mode */
    318       1.15      cgd #else
    319        1.1      cgd 	outb(IO_ICU1+1, 1);		/* 8086 mode */
    320       1.15      cgd #endif
    321        1.1      cgd 	outb(IO_ICU1+1, 0xff);		/* leave interrupts masked */
    322   1.28.2.8  mycroft 	outb(IO_ICU1, 0x0a);		/* default to IRR on read */
    323       1.21   andrew #ifdef REORDER_IRQ
    324       1.15      cgd 	outb(IO_ICU1, 0xc0 | (3 - 1));	/* pri order 3-7, 0-2 (com2 first) */
    325       1.21   andrew #endif
    326        1.1      cgd 
    327        1.1      cgd 	outb(IO_ICU2, 0x11);		/* reset; program device, four bytes */
    328   1.28.2.1  mycroft 	outb(IO_ICU2+1, ICU_OFFSET+8);	/* staring at this vector index */
    329   1.28.2.1  mycroft 	outb(IO_ICU2+1, ffs(IRQ_SLAVE)-1);
    330       1.15      cgd #ifdef AUTO_EOI_2
    331       1.15      cgd 	outb(IO_ICU2+1, 2 | 1);		/* auto EOI, 8086 mode */
    332       1.15      cgd #else
    333   1.28.2.1  mycroft 	outb(IO_ICU2+1, 1);		/* 8086 mode */
    334       1.15      cgd #endif
    335        1.1      cgd 	outb(IO_ICU2+1, 0xff);		/* leave interrupts masked */
    336       1.15      cgd 	outb(IO_ICU2, 0x0a);		/* default to IRR on read */
    337   1.28.2.8  mycroft }
    338   1.28.2.8  mycroft 
    339   1.28.2.8  mycroft /*
    340   1.28.2.9  mycroft  * Flush any pending interrupts.
    341   1.28.2.9  mycroft  */
    342   1.28.2.9  mycroft static void
    343   1.28.2.9  mycroft isa_flushintrs()
    344   1.28.2.9  mycroft {
    345   1.28.2.9  mycroft 	register int i;
    346   1.28.2.9  mycroft 
    347   1.28.2.9  mycroft 	/* clear any pending interrupts */
    348   1.28.2.9  mycroft 	for (i = 0; i < 8; i++) {
    349   1.28.2.9  mycroft 		outb(IO_ICU1, ICU_EOI);
    350   1.28.2.9  mycroft 		outb(IO_ICU2, ICU_EOI);
    351   1.28.2.9  mycroft 	}
    352   1.28.2.9  mycroft }
    353   1.28.2.9  mycroft 
    354   1.28.2.9  mycroft /*
    355   1.28.2.8  mycroft  * Determine what IRQ a device is using by trying to force it to generate an
    356   1.28.2.8  mycroft  * interrupt and seeing which IRQ line goes high.  It is not safe to call
    357   1.28.2.8  mycroft  * this function after autoconfig.
    358   1.28.2.8  mycroft  */
    359   1.28.2.8  mycroft u_short
    360   1.28.2.8  mycroft isa_discoverintr(force, aux)
    361   1.28.2.8  mycroft 	void (*force)();
    362   1.28.2.8  mycroft {
    363   1.28.2.8  mycroft 	int time = TIMER_FREQ * 1;	/* wait up to 1 second */
    364   1.28.2.8  mycroft 	u_int last, now;
    365   1.28.2.8  mycroft 	u_short iobase = IO_TIMER1;
    366   1.28.2.8  mycroft 
    367   1.28.2.9  mycroft 	isa_flushintrs();
    368   1.28.2.8  mycroft 	/* attempt to force interrupt */
    369   1.28.2.8  mycroft 	force(aux);
    370   1.28.2.8  mycroft 	/* set timer 2 to a known state */
    371   1.28.2.8  mycroft 	outb(iobase + TIMER_MODE, TIMER_SEL2|TIMER_RATEGEN|TIMER_16BIT);
    372   1.28.2.8  mycroft 	outb(iobase + TIMER_CNTR2, 0xff);
    373   1.28.2.8  mycroft 	outb(iobase + TIMER_CNTR2, 0xff);
    374   1.28.2.8  mycroft 	last = 0xffff;
    375   1.28.2.8  mycroft 	while (time > 0) {
    376   1.28.2.8  mycroft 		register u_char irr, lo, hi;
    377  1.28.2.10  mycroft 		irr = inb(IO_ICU1) & ~IRQ_SLAVE;
    378   1.28.2.8  mycroft 		if (irr)
    379   1.28.2.8  mycroft 			return 1 << (ffs(irr) - 1);
    380   1.28.2.8  mycroft 		irr = inb(IO_ICU2);
    381   1.28.2.8  mycroft 		if (irr)
    382   1.28.2.8  mycroft 			return 1 << (ffs(irr) + 7);
    383   1.28.2.8  mycroft 		outb(iobase + TIMER_MODE, TIMER_SEL2|TIMER_LATCH);
    384   1.28.2.8  mycroft 		lo = inb(iobase + TIMER_CNTR2);
    385   1.28.2.8  mycroft 		hi = inb(iobase + TIMER_CNTR2);
    386   1.28.2.8  mycroft 		now = (hi << 8) | lo;
    387   1.28.2.8  mycroft 		if (now <= last)
    388   1.28.2.8  mycroft 			time -= (last - now);
    389   1.28.2.8  mycroft 		else
    390  1.28.2.10  mycroft 			time -= 0x10000 - (now - last);
    391   1.28.2.8  mycroft 		last = now;
    392   1.28.2.8  mycroft 	}
    393   1.28.2.8  mycroft 	return IRQNONE;
    394        1.1      cgd }
    395        1.1      cgd 
    396        1.1      cgd /*
    397        1.1      cgd  * Handle a NMI, possibly a machine check.
    398        1.1      cgd  * return true to panic system, false to ignore.
    399   1.28.2.7  mycroft  *
    400   1.28.2.7  mycroft  * This implementation is hist[oe]rical.
    401        1.1      cgd  */
    402       1.21   andrew int
    403   1.28.2.7  mycroft isa_nmi()
    404   1.28.2.7  mycroft {
    405        1.1      cgd 
    406   1.28.2.7  mycroft 	log(LOG_CRIT, "NMI port 61 %x, port 70 %x\n", inb(0x61), inb(0x70));
    407   1.28.2.7  mycroft 	return 0;
    408        1.1      cgd }
    409        1.1      cgd 
    410        1.1      cgd /*
    411        1.1      cgd  * Caught a stray interrupt, notify
    412        1.1      cgd  */
    413       1.21   andrew void
    414   1.28.2.1  mycroft isa_strayintr(d)
    415   1.28.2.1  mycroft 	int d;
    416   1.28.2.1  mycroft {
    417   1.28.2.7  mycroft 	extern u_long intrcnt_stray;
    418        1.1      cgd 
    419        1.4      cgd 	/*
    420   1.28.2.1  mycroft 	 * Stray level 7 interrupts occur when someone raises an interrupt
    421   1.28.2.1  mycroft 	 * and then drops it before the CPU acknowledges it.  This means
    422   1.28.2.7  mycroft 	 * either the device is screwed or something is cli'ing too long
    423   1.28.2.7  mycroft 	 * and it's timing out.
    424   1.28.2.7  mycroft 	 *
    425   1.28.2.7  mycroft 	 * -1 is passed by the generic handler for out of range exceptions,
    426   1.28.2.7  mycroft 	 * since we don't really want 208 little vectors.  (It wouldn't be
    427   1.28.2.7  mycroft 	 * all that much code, but why bother?)
    428        1.4      cgd 	 */
    429   1.28.2.7  mycroft 	if (intrcnt_stray++ < 5)
    430   1.28.2.7  mycroft 		if (d == -1)
    431   1.28.2.7  mycroft 			log(LOG_ERR, "wild interrupt\n");
    432   1.28.2.7  mycroft 		else
    433   1.28.2.7  mycroft 			log(LOG_ERR, "stray interrupt %d\n", d);
    434       1.15      cgd 	if (intrcnt_stray == 5)
    435   1.28.2.7  mycroft 		log(LOG_ERR, "too many stray interrupts; stopped logging\n");
    436        1.1      cgd }
    437        1.1      cgd 
    438   1.28.2.7  mycroft static int beeping;
    439   1.28.2.7  mycroft 
    440       1.21   andrew static void
    441       1.21   andrew sysbeepstop(int f)
    442        1.1      cgd {
    443       1.16  mycroft 
    444        1.1      cgd 	/* disable counter 2 */
    445       1.16  mycroft 	disable_intr();
    446       1.28   brezak 	outb(PITAUX_PORT, inb(PITAUX_PORT) & ~PIT_SPKR);
    447       1.16  mycroft 	enable_intr();
    448        1.1      cgd 	if (f)
    449       1.24  deraadt 		timeout((timeout_t)sysbeepstop, (caddr_t)0, f);
    450        1.1      cgd 	else
    451        1.1      cgd 		beeping = 0;
    452        1.1      cgd }
    453        1.1      cgd 
    454       1.21   andrew void
    455       1.21   andrew sysbeep(int pitch, int period)
    456        1.1      cgd {
    457       1.16  mycroft 	static int last_pitch, last_period;
    458        1.1      cgd 
    459       1.16  mycroft 	if (beeping) {
    460       1.24  deraadt 		untimeout((timeout_t)sysbeepstop, (caddr_t)(last_period/2));
    461       1.24  deraadt 		untimeout((timeout_t)sysbeepstop, (caddr_t)0);
    462        1.1      cgd 	}
    463       1.16  mycroft 	if (!beeping || last_pitch != pitch) {
    464       1.16  mycroft 		/*
    465   1.28.2.7  mycroft 		 * XXX - move timer stuff to clock.c.
    466   1.28.2.7  mycroft 		 */
    467       1.16  mycroft 		disable_intr();
    468       1.16  mycroft 		outb(TIMER_MODE, TIMER_SEL2|TIMER_16BIT|TIMER_SQWAVE);
    469   1.28.2.7  mycroft 		outb(TIMER_CNTR2, TIMER_DIV(pitch));
    470   1.28.2.7  mycroft 		outb(TIMER_CNTR2, TIMER_DIV(pitch)>>8);
    471       1.28   brezak 		outb(PITAUX_PORT, inb(PITAUX_PORT) | PIT_SPKR);	/* enable counter 2 */
    472       1.16  mycroft 		enable_intr();
    473       1.16  mycroft 	}
    474       1.16  mycroft 	last_pitch = pitch;
    475       1.16  mycroft 	beeping = last_period = period;
    476       1.24  deraadt 	timeout((timeout_t)sysbeepstop, (caddr_t)(period/2), period);
    477        1.1      cgd }
    478