574 lines
15 KiB
C
574 lines
15 KiB
C
/*-
|
|
* Copyright (c) 1991 The Regents of the University of California.
|
|
* All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to Berkeley by
|
|
* William Jolitz.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by the University of
|
|
* California, Berkeley and its contributors.
|
|
* 4. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* @(#)isa.c 7.2 (Berkeley) 5/13/91
|
|
*/
|
|
static char rcsid[] = "$Header: /cvsroot/src/sys/dev/isa/isa.c,v 1.3 1993/04/08 08:26:55 deraadt 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_DMA1 + 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(struct isa_device *, u_short *);
|
|
#ifdef notyet
|
|
struct rlist *isa_iomem;
|
|
|
|
/*
|
|
* Configure all ISA devices
|
|
*/
|
|
isa_configure() {
|
|
struct isa_device *dvp;
|
|
struct isa_driver *dp;
|
|
|
|
splhigh();
|
|
INTREN(IRQ_SLAVE);
|
|
/*rlist_free(&isa_iomem, 0xa0000, 0xfffff);*/
|
|
for (dvp = isa_devtab_tty; dvp; dvp++)
|
|
(void) config_isadev(dvp, &ttymask);
|
|
for (dvp = isa_devtab_bio; dvp; dvp++)
|
|
(void) config_isadev(dvp, &biomask);
|
|
for (dvp = isa_devtab_net; dvp; dvp++)
|
|
(void) config_isadev(dvp, &netmask);
|
|
for (dvp = isa_devtab_null; dvp; dvp++)
|
|
(void) config_isadev(dvp, 0);
|
|
#include "sl.h"
|
|
#if NSL > 0
|
|
netmask |= ttymask;
|
|
ttymask |= netmask;
|
|
#endif
|
|
/* 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_short *mp;
|
|
{
|
|
struct isa_driver *dp;
|
|
static short drqseen, irqseen;
|
|
|
|
if (dp = isdp->id_driver) {
|
|
/* if a device with i/o memory, convert to virtual address */
|
|
if (isdp->id_maddr) {
|
|
extern unsigned int atdevbase;
|
|
|
|
isdp->id_maddr -= IOM_BEGIN;
|
|
isdp->id_maddr += atdevbase;
|
|
}
|
|
isdp->id_alive = (*dp->probe)(isdp);
|
|
if (isdp->id_alive) {
|
|
|
|
printf("%s%d at port 0x%x ", dp->name,
|
|
isdp->id_unit, isdp->id_iobase);
|
|
|
|
/* check for conflicts */
|
|
if (irqseen & isdp->id_irq) {
|
|
printf("INTERRUPT CONFLICT - irq%d\n",
|
|
ffs(isdp->id_irq) - 1);
|
|
return (0);
|
|
}
|
|
if (isdp->id_drq != -1
|
|
&& (drqseen & (1<<isdp->id_drq))) {
|
|
printf("DMA CONFLICT - drq%d\n", isdp->id_drq);
|
|
return (0);
|
|
}
|
|
/* NEED TO CHECK IOMEM CONFLICT HERE */
|
|
|
|
/* allocate and wire in device */
|
|
if(isdp->id_irq) {
|
|
int intrno;
|
|
|
|
intrno = ffs(isdp->id_irq)-1;
|
|
printf("irq %d ", intrno);
|
|
INTREN(isdp->id_irq);
|
|
if(mp)INTRMASK(*mp,isdp->id_irq);
|
|
setidt(NRSVIDT + intrno, isdp->id_intr,
|
|
SDT_SYS386IGT, SEL_KPL);
|
|
irqseen |= isdp->id_irq;
|
|
}
|
|
if (isdp->id_drq != -1) {
|
|
printf("drq %d ", isdp->id_drq);
|
|
drqseen |= 1 << isdp->id_drq;
|
|
}
|
|
|
|
(*dp->attach)(isdp);
|
|
|
|
printf("on isa\n");
|
|
}
|
|
return (1);
|
|
} else return(0);
|
|
}
|
|
#else
|
|
/*
|
|
* Configure all ISA devices
|
|
*/
|
|
isa_configure() {
|
|
struct isa_device *dvp;
|
|
struct isa_driver *dp;
|
|
|
|
splhigh();
|
|
INTREN(IRQ_SLAVE);
|
|
for (dvp = isa_devtab_tty; config_isadev(dvp,&ttymask); dvp++);
|
|
for (dvp = isa_devtab_bio; config_isadev(dvp,&biomask); dvp++);
|
|
for (dvp = isa_devtab_net; config_isadev(dvp,&netmask); dvp++);
|
|
for (dvp = isa_devtab_null; config_isadev(dvp,0); dvp++);
|
|
#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_short *mp;
|
|
{
|
|
struct isa_driver *dp;
|
|
|
|
if (dp = isdp->id_driver) {
|
|
if (isdp->id_maddr) {
|
|
extern u_int atdevbase;
|
|
|
|
isdp->id_maddr -= 0xa0000;
|
|
isdp->id_maddr += atdevbase;
|
|
}
|
|
isdp->id_alive = (*dp->probe)(isdp);
|
|
if (isdp->id_alive) {
|
|
printf("%s%d", dp->name, isdp->id_unit);
|
|
printf(" at 0x%x ", isdp->id_iobase);
|
|
if(isdp->id_irq)
|
|
printf("irq %d ", ffs(isdp->id_irq)-1);
|
|
if (isdp->id_drq != -1)
|
|
printf("drq %d ", isdp->id_drq);
|
|
printf("on isa\n");
|
|
|
|
(*dp->attach)(isdp);
|
|
if(isdp->id_irq) {
|
|
int intrno;
|
|
|
|
intrno = ffs(isdp->id_irq)-1;
|
|
INTREN(isdp->id_irq);
|
|
if(mp)
|
|
INTRMASK(*mp,isdp->id_irq);
|
|
setidt(ICU_OFFSET+intrno, isdp->id_intr,
|
|
SDT_SYS386IGT, SEL_KPL);
|
|
}
|
|
}
|
|
return (1);
|
|
} else return(0);
|
|
}
|
|
#endif
|
|
|
|
#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);
|
|
|
|
/* clear npx intr latch */
|
|
outb(0xf1,0);
|
|
|
|
/* 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 */
|
|
outb(IO_ICU1+1, 1); /* 8086 mode */
|
|
outb(IO_ICU1+1, 0xff); /* leave interrupts masked */
|
|
outb(IO_ICU1, 2); /* default to ISR on read */
|
|
|
|
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 */
|
|
outb(IO_ICU2+1,1); /* 8086 mode */
|
|
outb(IO_ICU2+1, 0xff); /* leave interrupts masked */
|
|
outb(IO_ICU2, 2); /* default to ISR 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;
|
|
sleep(&isaphysmemflag, PRIBIO);
|
|
}
|
|
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) {
|
|
|
|
#ifdef notdef
|
|
/* DON'T BOTHER FOR NOW! */
|
|
/* for some reason, we get bursts of intr #7, even if not enabled! */
|
|
log(LOG_ERR,"ISA strayintr %x", d);
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Wait "n" microseconds. Relies on timer 0 to have 1Mhz clock, regardless
|
|
* of processor board speed. Note: timer had better have been programmed
|
|
* before this is first used!
|
|
*/
|
|
DELAY(n) {
|
|
int tick = getit(0,0) & 1;
|
|
|
|
while (n--) {
|
|
/* wait approximately 1 micro second */
|
|
while (tick == getit(0,0) & 1) ;
|
|
|
|
tick = getit(0,0) & 1;
|
|
}
|
|
}
|
|
|
|
getit(unit, timer) {
|
|
int port = (unit ? IO_TIMER2 : IO_TIMER1) + timer, val;
|
|
|
|
val = inb(port);
|
|
val = (inb(port) << 8) + val;
|
|
return (val);
|
|
}
|
|
|
|
extern int hz;
|
|
|
|
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 */
|
|
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));
|
|
}
|