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2fc79c3815
freebsd-dev/sys/i386/isa/isa.c
Andrew Moore 2fc79c3815 Applied David Greenman's hack to disable IRQ conflict checking 
when COM_MULTIPORT is defined.
1993-11-09 02:12:36 +00:00

794 lines
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/*-
* Copyright (c) 1991 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: @(#)isa.c 7.2 (Berkeley) 5/13/91
* $Id: isa.c,v 1.6 1993/11/07 21:47:19 wollman Exp $
*/
/*
* code to manage AT bus
*
* 92/08/18 Frank P. MacLachlan (fpm@crash.cts.com):
* Fixed uninitialized variable problem and added code to deal
* with DMA page boundaries in isa_dmarangecheck(). Fixed word
* mode DMA count compution and reorganized DMA setup code in
* isa_dmastart()
*/
#include "param.h"
#include "systm.h"
#include "conf.h"
#include "file.h"
#include "buf.h"
#include "uio.h"
#include "syslog.h"
#include "malloc.h"
#include "rlist.h"
#include "machine/segments.h"
#include "vm/vm.h"
#include "i386/isa/isa_device.h"
#include "i386/isa/isa.h"
#include "i386/isa/icu.h"
#include "i386/isa/ic/i8237.h"
#include "i386/isa/ic/i8042.h"
/*
** Register definitions for DMA controller 1 (channels 0..3):
*/
#define DMA1_CHN(c) (IO_DMA1 + 1*(2*(c))) /* addr reg for channel c */
#define DMA1_SMSK (IO_DMA1 + 1*10) /* single mask register */
#define DMA1_MODE (IO_DMA1 + 1*11) /* mode register */
#define DMA1_FFC (IO_DMA1 + 1*12) /* clear first/last FF */
/*
** Register definitions for DMA controller 2 (channels 4..7):
*/
#define DMA2_CHN(c) (IO_DMA2 + 2*(2*(c))) /* addr reg for channel c */
#define DMA2_SMSK (IO_DMA2 + 2*10) /* single mask register */
#define DMA2_MODE (IO_DMA2 + 2*11) /* mode register */
#define DMA2_FFC (IO_DMA2 + 2*12) /* clear first/last FF */
int config_isadev __P((struct isa_device *, u_int *));
/*
* print a conflict message
*/
void
conflict(dvp, tmpdvp, item, reason, format)
struct isa_device *dvp, *tmpdvp;
int item;
char *reason;
char *format;
{
printf("%s%d not probed due to %s conflict with %s%d at ",
dvp->id_driver->name, dvp->id_unit, reason,
tmpdvp->id_driver->name, tmpdvp->id_unit);
printf(format, item);
printf("\n");
}
/*
* Check to see if things are alread in use, like IRQ's, I/O addresses
* and Memory addresses.
*/
int
haveseen(dvp, tmpdvp)
struct isa_device *dvp, *tmpdvp;
{
int status = 0;
/*
* Only check against devices that have already been found
*/
if (tmpdvp->id_alive) {
/*
* Check for I/O address conflict. We can only check the
* starting address of the device against the range of the
* device that has already been probed since we do not
* know how many I/O addresses this device uses.
*/
if (tmpdvp->id_alive != -1) {
if ((dvp->id_iobase >= tmpdvp->id_iobase) &&
(dvp->id_iobase <=
(tmpdvp->id_iobase + tmpdvp->id_alive - 1))) {
conflict(dvp, tmpdvp, dvp->id_iobase,
"I/O address", "0x%x");
status = 1;
}
}
/*
* Check for Memory address conflict. We can check for
* range overlap, but it will not catch all cases since the
* driver may adjust the msize paramater during probe, for
* now we just check that the starting address does not
* fall within any allocated region.
* XXX could add a second check after the probe for overlap,
* since at that time we would know the full range.
* XXX KERNBASE is a hack, we should have vaddr in the table!
*/
if(tmpdvp->id_maddr) {
if((KERNBASE + dvp->id_maddr >= tmpdvp->id_maddr) &&
(KERNBASE + dvp->id_maddr <=
(tmpdvp->id_maddr + tmpdvp->id_msize - 1))) {
conflict(dvp, tmpdvp, dvp->id_maddr, "maddr",
"0x%x");
status = 1;
}
}
#ifndef COM_MULTIPORT
/*
* Check for IRQ conflicts.
*/
if(tmpdvp->id_irq) {
if (tmpdvp->id_irq == dvp->id_irq) {
conflict(dvp, tmpdvp, ffs(dvp->id_irq) - 1,
"irq", "%d");
status = 1;
}
}
#endif
/*
* Check for DRQ conflicts.
*/
if(tmpdvp->id_drq != -1) {
if (tmpdvp->id_drq == dvp->id_drq) {
conflict(dvp, tmpdvp, dvp->id_drq,
"drq", "%d");
status = 1;
}
}
}
return (status);
}
/*
* Search through all the isa_devtab_* tables looking for anything that
* conflicts with the current device.
*/
int
haveseen_isadev(dvp)
struct isa_device *dvp;
{
struct isa_device *tmpdvp;
int status = 0;
for (tmpdvp = isa_devtab_tty; tmpdvp->id_driver; tmpdvp++) {
status |= haveseen(dvp, tmpdvp);
}
for (tmpdvp = isa_devtab_bio; tmpdvp->id_driver; tmpdvp++) {
status |= haveseen(dvp, tmpdvp);
}
for (tmpdvp = isa_devtab_net; tmpdvp->id_driver; tmpdvp++) {
status |= haveseen(dvp, tmpdvp);
}
for (tmpdvp = isa_devtab_null; tmpdvp->id_driver; tmpdvp++) {
status |= haveseen(dvp, tmpdvp);
}
return(status);
}
/*
* Configure all ISA devices
*/
void
isa_configure() {
struct isa_device *dvp;
enable_intr();
splhigh();
INTREN(IRQ_SLAVE);
printf("Probing for devices on the ISA bus:\n");
for (dvp = isa_devtab_tty; dvp->id_driver; dvp++) {
if (!haveseen_isadev(dvp))
config_isadev(dvp,&ttymask);
}
for (dvp = isa_devtab_bio; dvp->id_driver; dvp++) {
if (!haveseen_isadev(dvp))
config_isadev(dvp,&biomask);
}
for (dvp = isa_devtab_net; dvp->id_driver; dvp++) {
if (!haveseen_isadev(dvp))
config_isadev(dvp,&netmask);
}
for (dvp = isa_devtab_null; dvp->id_driver; dvp++) {
if (!haveseen_isadev(dvp))
config_isadev(dvp,(u_int *) NULL);
}
/*
* XXX We should really add the tty device to netmask when the line is
* switched to SLIPDISC, and then remove it when it is switched away from
* SLIPDISC. No need to block out ALL ttys during a splnet when only one
* of them is running slip.
*/
#include "sl.h"
#if NSL > 0
netmask |= ttymask;
ttymask |= netmask;
#endif
/* biomask |= ttymask ; can some tty devices use buffers? */
printf("biomask %x ttymask %x netmask %x\n", biomask, ttymask, netmask);
splnone();
}
/*
* Configure an ISA device.
*/
config_isadev(isdp, mp)
struct isa_device *isdp;
u_int *mp;
{
struct isa_driver *dp = isdp->id_driver;
if (isdp->id_maddr) {
extern u_int atdevbase;
isdp->id_maddr -= 0xa0000; /* XXX should be a define */
isdp->id_maddr += atdevbase;
}
isdp->id_alive = (*dp->probe)(isdp);
if (isdp->id_alive) {
/*
* Only print the I/O address range if id_alive != -1
* Right now this is a temporary fix just for the new
* NPX code so that if it finds a 486 that can use trap
* 16 it will not report I/O addresses.
* Rod Grimes 04/26/94
*/
printf("%s%d", dp->name, isdp->id_unit);
if (isdp->id_alive != -1) {
printf(" at 0x%x", isdp->id_iobase);
if ((isdp->id_iobase + isdp->id_alive - 1) !=
isdp->id_iobase) {
printf("-0x%x",
isdp->id_iobase +
isdp->id_alive - 1);
}
}
if(isdp->id_irq)
printf(" irq %d", ffs(isdp->id_irq) - 1);
if (isdp->id_drq != -1)
printf(" drq %d", isdp->id_drq);
if (isdp->id_maddr)
printf(" maddr 0x%x", kvtop(isdp->id_maddr));
if (isdp->id_msize)
printf(" msize %d", isdp->id_msize);
if (isdp->id_flags)
printf(" flags 0x%x", isdp->id_flags);
if (isdp->id_iobase < 0x100)
printf(" on motherboard\n");
else
printf(" on isa\n");
(*dp->attach)(isdp);
if(isdp->id_irq) {
int intrno;
intrno = ffs(isdp->id_irq)-1;
setidt(ICU_OFFSET+intrno, isdp->id_intr,
SDT_SYS386IGT, SEL_KPL);
if(mp) {
INTRMASK(*mp,isdp->id_irq);
}
INTREN(isdp->id_irq);
}
} else {
printf("%s%d not found", dp->name, isdp->id_unit);
if (isdp->id_iobase) {
printf(" at 0x%x", isdp->id_iobase);
}
printf("\n");
}
}
#define IDTVEC(name) __CONCAT(X,name)
/* default interrupt vector table entries */
extern IDTVEC(intr0), IDTVEC(intr1), IDTVEC(intr2), IDTVEC(intr3),
IDTVEC(intr4), IDTVEC(intr5), IDTVEC(intr6), IDTVEC(intr7),
IDTVEC(intr8), IDTVEC(intr9), IDTVEC(intr10), IDTVEC(intr11),
IDTVEC(intr12), IDTVEC(intr13), IDTVEC(intr14), IDTVEC(intr15);
static *defvec[16] = {
&IDTVEC(intr0), &IDTVEC(intr1), &IDTVEC(intr2), &IDTVEC(intr3),
&IDTVEC(intr4), &IDTVEC(intr5), &IDTVEC(intr6), &IDTVEC(intr7),
&IDTVEC(intr8), &IDTVEC(intr9), &IDTVEC(intr10), &IDTVEC(intr11),
&IDTVEC(intr12), &IDTVEC(intr13), &IDTVEC(intr14), &IDTVEC(intr15) };
/* out of range default interrupt vector gate entry */
extern IDTVEC(intrdefault);
/*
* Fill in default interrupt table (in case of spuruious interrupt
* during configuration of kernel, setup interrupt control unit
*/
isa_defaultirq() {
int i;
/* icu vectors */
for (i = NRSVIDT ; i < NRSVIDT+ICU_LEN ; i++)
setidt(i, defvec[i], SDT_SYS386IGT, SEL_KPL);
/* out of range vectors */
for (i = NRSVIDT; i < NIDT; i++)
setidt(i, &IDTVEC(intrdefault), SDT_SYS386IGT, SEL_KPL);
/* initialize 8259's */
outb(IO_ICU1, 0x11); /* reset; program device, four bytes */
outb(IO_ICU1+1, NRSVIDT); /* starting at this vector index */
outb(IO_ICU1+1, 1<<2); /* slave on line 2 */
#ifdef AUTO_EOI_1
outb(IO_ICU1+1, 2 | 1); /* auto EOI, 8086 mode */
#else
outb(IO_ICU1+1, 1); /* 8086 mode */
#endif
outb(IO_ICU1+1, 0xff); /* leave interrupts masked */
outb(IO_ICU1, 0x0a); /* default to IRR on read */
outb(IO_ICU1, 0xc0 | (3 - 1)); /* pri order 3-7, 0-2 (com2 first) */
outb(IO_ICU2, 0x11); /* reset; program device, four bytes */
outb(IO_ICU2+1, NRSVIDT+8); /* staring at this vector index */
outb(IO_ICU2+1,2); /* my slave id is 2 */
#ifdef AUTO_EOI_2
outb(IO_ICU2+1, 2 | 1); /* auto EOI, 8086 mode */
#else
outb(IO_ICU2+1,1); /* 8086 mode */
#endif
outb(IO_ICU2+1, 0xff); /* leave interrupts masked */
outb(IO_ICU2, 0x0a); /* default to IRR on read */
}
/* region of physical memory known to be contiguous */
vm_offset_t isaphysmem;
static caddr_t dma_bounce[8]; /* XXX */
static char bounced[8]; /* XXX */
#define MAXDMASZ 512 /* XXX */
/* high byte of address is stored in this port for i-th dma channel */
static short dmapageport[8] =
{ 0x87, 0x83, 0x81, 0x82, 0x8f, 0x8b, 0x89, 0x8a };
/*
* isa_dmacascade(): program 8237 DMA controller channel to accept
* external dma control by a board.
*/
void isa_dmacascade(unsigned chan)
{
if (chan > 7)
panic("isa_dmacascade: impossible request");
/* set dma channel mode, and set dma channel mode */
if ((chan & 4) == 0) {
outb(DMA1_MODE, DMA37MD_CASCADE | chan);
outb(DMA1_SMSK, chan);
} else {
outb(DMA2_MODE, DMA37MD_CASCADE | (chan & 3));
outb(DMA2_SMSK, chan & 3);
}
}
/*
* isa_dmastart(): program 8237 DMA controller channel, avoid page alignment
* problems by using a bounce buffer.
*/
void isa_dmastart(int flags, caddr_t addr, unsigned nbytes, unsigned chan)
{ vm_offset_t phys;
int waport;
caddr_t newaddr;
if ( chan > 7
|| (chan < 4 && nbytes > (1<<16))
|| (chan >= 4 && (nbytes > (1<<17) || (u_int)addr & 1)))
panic("isa_dmastart: impossible request");
if (isa_dmarangecheck(addr, nbytes, chan)) {
if (dma_bounce[chan] == 0)
dma_bounce[chan] =
/*(caddr_t)malloc(MAXDMASZ, M_TEMP, M_WAITOK);*/
(caddr_t) isaphysmem + NBPG*chan;
bounced[chan] = 1;
newaddr = dma_bounce[chan];
*(int *) newaddr = 0; /* XXX */
/* copy bounce buffer on write */
if (!(flags & B_READ))
bcopy(addr, newaddr, nbytes);
addr = newaddr;
}
/* translate to physical */
phys = pmap_extract(pmap_kernel(), (vm_offset_t)addr);
if ((chan & 4) == 0) {
/*
* Program one of DMA channels 0..3. These are
* byte mode channels.
*/
/* set dma channel mode, and reset address ff */
if (flags & B_READ)
outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|chan);
else
outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_READ|chan);
outb(DMA1_FFC, 0);
/* send start address */
waport = DMA1_CHN(chan);
outb(waport, phys);
outb(waport, phys>>8);
outb(dmapageport[chan], phys>>16);
/* send count */
outb(waport + 1, --nbytes);
outb(waport + 1, nbytes>>8);
/* unmask channel */
outb(DMA1_SMSK, chan);
} else {
/*
* Program one of DMA channels 4..7. These are
* word mode channels.
*/
/* set dma channel mode, and reset address ff */
if (flags & B_READ)
outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|(chan&3));
else
outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_READ|(chan&3));
outb(DMA2_FFC, 0);
/* send start address */
waport = DMA2_CHN(chan - 4);
outb(waport, phys>>1);
outb(waport, phys>>9);
outb(dmapageport[chan], phys>>16);
/* send count */
nbytes >>= 1;
outb(waport + 2, --nbytes);
outb(waport + 2, nbytes>>8);
/* unmask channel */
outb(DMA2_SMSK, chan & 3);
}
}
void isa_dmadone(int flags, caddr_t addr, int nbytes, int chan)
{
/* copy bounce buffer on read */
/*if ((flags & (B_PHYS|B_READ)) == (B_PHYS|B_READ))*/
if (bounced[chan]) {
bcopy(dma_bounce[chan], addr, nbytes);
bounced[chan] = 0;
}
}
/*
* Check for problems with the address range of a DMA transfer
* (non-contiguous physical pages, outside of bus address space,
* crossing DMA page boundaries).
* Return true if special handling needed.
*/
isa_dmarangecheck(caddr_t va, unsigned length, unsigned chan) {
vm_offset_t phys, priorpage = 0, endva;
u_int dma_pgmsk = (chan & 4) ? ~(128*1024-1) : ~(64*1024-1);
endva = (vm_offset_t)round_page(va + length);
for (; va < (caddr_t) endva ; va += NBPG) {
phys = trunc_page(pmap_extract(pmap_kernel(), (vm_offset_t)va));
#define ISARAM_END RAM_END
if (phys == 0)
panic("isa_dmacheck: no physical page present");
if (phys > ISARAM_END)
return (1);
if (priorpage) {
if (priorpage + NBPG != phys)
return (1);
/* check if crossing a DMA page boundary */
if (((u_int)priorpage ^ (u_int)phys) & dma_pgmsk)
return (1);
}
priorpage = phys;
}
return (0);
}
/* head of queue waiting for physmem to become available */
struct buf isa_physmemq;
/* blocked waiting for resource to become free for exclusive use */
static isaphysmemflag;
/* if waited for and call requested when free (B_CALL) */
static void (*isaphysmemunblock)(); /* needs to be a list */
/*
* Allocate contiguous physical memory for transfer, returning
* a *virtual* address to region. May block waiting for resource.
* (assumed to be called at splbio())
*/
caddr_t
isa_allocphysmem(caddr_t va, unsigned length, void (*func)()) {
isaphysmemunblock = func;
while (isaphysmemflag & B_BUSY) {
isaphysmemflag |= B_WANTED;
tsleep(&isaphysmemflag, PRIBIO, "isaphys", 0);
}
isaphysmemflag |= B_BUSY;
return((caddr_t)isaphysmem);
}
/*
* Free contiguous physical memory used for transfer.
* (assumed to be called at splbio())
*/
void
isa_freephysmem(caddr_t va, unsigned length) {
isaphysmemflag &= ~B_BUSY;
if (isaphysmemflag & B_WANTED) {
isaphysmemflag &= B_WANTED;
wakeup(&isaphysmemflag);
if (isaphysmemunblock)
(*isaphysmemunblock)();
}
}
/*
* Handle a NMI, possibly a machine check.
* return true to panic system, false to ignore.
*/
isa_nmi(cd) {
log(LOG_CRIT, "\nNMI port 61 %x, port 70 %x\n", inb(0x61), inb(0x70));
return(0);
}
/*
* Caught a stray interrupt, notify
*/
isa_strayintr(d) {
/* DON'T BOTHER FOR NOW! */
/* for some reason, we get bursts of intr #7, even if not enabled! */
/*
* Well the reason you got bursts of intr #7 is because someone
* raised an interrupt line and dropped it before the 8259 could
* prioritize it. This is documented in the intel data book. This
* means you have BAD hardware! I have changed this so that only
* the first 5 get logged, then it quits logging them, and puts
* out a special message. rgrimes 3/25/1993
*/
extern u_long intrcnt_stray;
intrcnt_stray++;
if (intrcnt_stray <= 5)
log(LOG_ERR,"ISA strayintr %x\n", d);
if (intrcnt_stray == 5)
log(LOG_CRIT,"Too many ISA strayintr not logging any more\n");
}
/*
* Wait "n" microseconds.
* Relies on timer 1 counting down from (TIMER_FREQ / hz) at
* (1 * TIMER_FREQ) Hz.
* Note: timer had better have been programmed before this is first used!
* (The standard programming causes the timer to generate a square wave and
* the counter is decremented twice every cycle.)
*/
#define CF (1 * TIMER_FREQ)
#define TIMER_FREQ 1193182 /* XXX - should be elsewhere */
extern int hz; /* XXX - should be elsewhere */
int DELAY(n)
int n;
{
int counter_limit;
int prev_tick;
int tick;
int ticks_left;
int sec;
int usec;
#ifdef DELAYDEBUG
int getit_calls = 1;
int n1;
static int state = 0;
if (state == 0) {
state = 1;
for (n1 = 1; n1 <= 10000000; n1 *= 10)
DELAY(n1);
state = 2;
}
if (state == 1)
printf("DELAY(%d)...", n);
#endif
/*
* Read the counter first, so that the rest of the setup overhead is
* counted. Guess the initial overhead is 20 usec (on most systems it
* takes about 1.5 usec for each of the i/o's in getit(). The loop
* takes about 6 usec on a 486/33 and 13 usec on a 386/20. The
* multiplications and divisions to scale the count take a while).
*/
prev_tick = getit(0, 0);
n -= 20;
/*
* Calculate (n * (CF / 1e6)) without using floating point and without
* any avoidable overflows.
*/
sec = n / 1000000;
usec = n - sec * 1000000;
ticks_left = sec * CF
+ usec * (CF / 1000000)
+ usec * ((CF % 1000000) / 1000) / 1000
+ usec * (CF % 1000) / 1000000;
counter_limit = TIMER_FREQ / hz;
while (ticks_left > 0) {
tick = getit(0, 0);
#ifdef DELAYDEBUG
++getit_calls;
#endif
if (tick > prev_tick)
ticks_left -= prev_tick - (tick - counter_limit);
else
ticks_left -= prev_tick - tick;
prev_tick = tick;
}
#ifdef DELAYDEBUG
if (state == 1)
printf(" %d calls to getit() at %d usec each\n",
getit_calls, (n + 5) / getit_calls);
#endif
}
getit(unit, timer) {
int high;
int low;
/*
* XXX - isa.h defines bogus timers. There's no such timer as
* IO_TIMER_2 = 0x48. There's a timer in the CMOS RAM chip but
* its interface is quite different. Neither timer is an 8252.
* We actually only call this with unit = 0 and timer = 0. It
* could be static...
*/
/*
* Protect ourself against interrupts.
* XXX - sysbeep() and sysbeepstop() need protection.
*/
disable_intr();
/*
* Latch the count for 'timer' (cc00xxxx, c = counter, x = any).
*/
outb(IO_TIMER1 + 3, timer << 6);
low = inb(IO_TIMER1 + timer);
high = inb(IO_TIMER1 + timer);
enable_intr();
return ((high << 8) | low);
}
static beeping;
static
sysbeepstop(f)
{
/* disable counter 2 */
outb(0x61, inb(0x61) & 0xFC);
if (f)
timeout(sysbeepstop, 0, f);
else
beeping = 0;
}
void sysbeep(int pitch, int period)
{
outb(0x61, inb(0x61) | 3); /* enable counter 2 */
/*
* XXX - move timer stuff to clock.c.
* Program counter 2:
* ccaammmb, c counter, a = access, m = mode, b = BCD
* 1011x110, 11 for aa = LSB then MSB, x11 for mmm = square wave.
*/
outb(0x43, 0xb6); /* set command for counter 2, 2 byte write */
outb(0x42, pitch);
outb(0x42, (pitch>>8));
if (!beeping) {
beeping = period;
timeout(sysbeepstop, period/2, period);
}
}
/*
* Pass command to keyboard controller (8042)
*/
unsigned kbc_8042cmd(val) {
while (inb(KBSTATP)&KBS_IBF);
if (val) outb(KBCMDP, val);
while (inb(KBSTATP)&KBS_IBF);
return (inb(KBDATAP));
}
/*
* find an ISA device in a given isa_devtab_* table, given
* the table to search, the expected id_driver entry, and the unit number.
*
* this function is defined in isa_device.h, and this location is debatable;
* i put it there because it's useless w/o, and directly operates on
* the other stuff in that file.
*
*/
struct isa_device *find_isadev(table, driverp, unit)
struct isa_device *table;
struct isa_driver *driverp;
int unit;
{
if (driverp == NULL) /* sanity check */
return NULL;
while ((table->id_driver != driverp) || (table->id_unit != unit)) {
if (table->id_driver == 0)
return NULL;
table++;
}
return table;
}
/*
* Return nonzero if a (masked) irq is pending for a given device.
*/
int
isa_irq_pending(dvp)
struct isa_device *dvp;
{
unsigned id_irq;
id_irq = (unsigned short) dvp->id_irq; /* XXX silly type in struct */
if (id_irq & 0xff)
return (inb(IO_ICU1) & id_irq);
return (inb(IO_ICU2) & (id_irq >> 8));
}
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