/* $NetBSD: fd.c,v 1.12 2022/08/07 11:06:18 andvar Exp $ */
/*-
* Copyright (C) 1997-1998 Kazuki Sakamoto (sakamoto@NetBSD.org)
* All rights reserved.
*
* Floppy Disk Drive standalone device driver
*
* 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 Kazuki Sakamoto.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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/param.h>
#include <lib/libsa/stand.h>
#include "boot.h"
/*---------------------------------------------------------------------------*
* Floppy Disk Controller Define *
*---------------------------------------------------------------------------*/
/* Floppy Disk Controller Registers */
int FDC_PORT[] = { /* fdc base I/O port */
0x3f0, /* primary */
};
#define FDC_DOR(x) (FDC_PORT[x] + 0x2) /* motor drive control bits */
#define FDC_STATUS(x) (FDC_PORT[x] + 0x4) /* fdc main status register */
#define FDC_DATA(x) (FDC_PORT[x] + 0x5) /* fdc data register */
#define FDC_RATE(x) (FDC_PORT[x] + 0x7) /* transfer rate register */
#define FDC_IRQ 6
#define FD_DMA_CHAN 2
/* fdc main status register */
#define RQM 0x80 /* the host can transfer data if set */
#define DIO 0x40 /* direction of data transfer. write required if set */
#define NON_DMA 0x20 /* fdc have date for transfer in non dma mode */
#define CMD_BUSY 0x10 /* command busy if set */
/* fdc result status */
#define ST0_IC_MASK 0xc0 /* interrupt code 00:normal terminate */
#define ST1_EN 0x80 /* end of cylinder */
/* fdc digtal output register */
#define DOR_DMAEN 0x08 /* DRQ, nDACK, TC and FINTR output enable */
#define DOR_RESET 0x04 /* fdc software reset */
/* fdc command */
#define CMD_RECALIBRATE 0x07 /* recalibrate */
#define CMD_SENSE_INT 0x08 /* sense interrupt status */
#define CMD_DRV_SENSE 0x04 /* sense drive status */
#define CMD_SEEK 0x0f /* seek */
#define CMD_FORMAT 0x4d /* format */
#define CMD_READ 0x46 /* read e6 */
#define CMD_WRITE 0xc5 /* write */
#define CMD_VERIFY 0xf6 /* verify */
#define CMD_READID 0x4a /* readID */
#define CMD_SPECIFY 0x03 /* specify */
#define CMD_CONFIG 0x13 /* config */
#define CMD_VERSION 0x10 /* version */
/* command specify value */
#define SPECIFY1 ((0x0d<<4)|0x0f)
#define SPECIFY2 ((0x01<<1)|0) /* DMA MODE */
/* fdc result */
#define STATUS_MAX 16 /* result status max number */
#define RESULT_VERSION 0x90 /* enhanced controller */
#define RESULT_SEEK 0x20 /* seek & recalibrate complete flag on status0 */
/*---------------------------------------------------------------------------*
* Floppy Disk Type Define *
*---------------------------------------------------------------------------*/
struct fdd_type {
int seccount; /* sector per track */
int secsize; /* byte per sector (uPD765 parameter) */
int datalen; /* data length */
int gap; /* gap */
int gaplen; /* gap length */
int cylinder; /* track per media */
int maxseccount; /* media max sector count */
int step; /* seek step */
int rate; /* drive rate (250 or 500kbps) */
int heads; /* heads */
int f_gap; /* format gap */
int mselect; /* drive mode select */
char *type_name; /* media type name */
};
typedef struct fdd_type FDDTYPE;
#define FDTYPE_MAX 5
FDDTYPE fdd_types[FDTYPE_MAX] = {
{ 18,2,0xff,0x1b,0x54,80,2880,1,0,2,0x6c,0,"2HQ" }, /* 2HD (PC/AT) */
{ 8,3,0xff,0x35,0x74,77,1232,1,0,2,0x54,1,"2HD" }, /* 2HD (98) */
{ 15,2,0xff,0x1b,0x54,80,2400,1,0,2,0x54,1,"2HC" }, /* 2HC */
{ 9,2,0xff,0x23,0x50,80,1440,1,2,2,0x50,1,"2DD9" },/* 2DD 9 sector */
{ 8,2,0xff,0x3a,0x50,80,1280,1,2,2,0x50,1,"2DD8" },/* 2DD 8 sector */
};
int fdsectors[] = {128, 256, 512, 1024, 2048, 4096};
#define SECTOR_MAX 4096
#define FDBLK (fdsectors[un->un_type->secsize])
#define START_CYL 0
#define START_SECTOR 1
#define DELAY(x) delay(100000 * x) /* about 100ms */
#define INT_TIMEOUT 3000000
/*---------------------------------------------------------------------------*
* FDC Device Driver Define *
*---------------------------------------------------------------------------*/
#define CTLR_MAX 1
#define UNIT_MAX 2
struct fd_unit {
int ctlr;
int unit;
u_int un_flags; /* unit status flag */
int stat[STATUS_MAX]; /* result code */
FDDTYPE *un_type; /* floppy type (pointer) */
};
typedef struct fd_unit FD_UNIT;
FD_UNIT fd_unit[CTLR_MAX][UNIT_MAX];
/*
* un_flags flags
*/
#define INT_ALIVE 0x00000001 /* Device is Alive and Available */
#define INT_READY 0x00000002 /* Device is Ready */
#define INT_BUSY 0x00000004 /* Device is busy */
/*---------------------------------------------------------------------------*
* Misc define *
*---------------------------------------------------------------------------*/
#define TIMEOUT 10000000
#define ND_TIMEOUT 10000000
#define SUCCESS 0
#define FAIL -1
/*
* function declaration
*/
int fdinit(FD_UNIT *);
int fdopen(struct open_file *, int, int);
int fdclose(struct open_file *);
int fdioctl(struct open_file *, u_long, void *);
int fdstrategy(void *, int, daddr_t, size_t, void *, size_t *);
int fdc_out(int, int);
int fdc_in(int, u_char *);
int fdc_intr_wait(void);
int fd_check(FD_UNIT *);
void motor_on(int, int);
void motor_off(int, int);
void fdReset(int);
void fdRecalibrate(int, int);
void fdSpecify(int);
void fdDriveStatus(int, int, int, int *);
int fdSeek(int, int, int);
int fdSenseInt(int, int *);
int fdReadWrite(FD_UNIT *, int, int, int, int, u_char *);
void irq_init(void);
int irq_polling(int, int);
void dma_setup(u_char *, int, int, int);
int dma_finished(int);
/*===========================================================================*
* fdinit *
*===========================================================================*/
int
fdinit(FD_UNIT *un)
{
int ctlr = un->ctlr;
u_char result;
#if 0
irq_init();
#endif
fdReset(ctlr);
if (fdc_out(ctlr, CMD_VERSION) != SUCCESS) { /* version check */
printf ("fdc%d:fatal error: CMD_VERSION cmd fail\n", ctlr);
return (FAIL);
}
if (fdc_in(ctlr, &result) != SUCCESS) {
printf ("fdc%d:fatal error: CMD_VERSION exec fail\n", ctlr);
return (FAIL);
}
if (result != (u_char)RESULT_VERSION) {
printf ("fdc%d:fatal error: unknown version fdc\n", ctlr);
return (FAIL);
}
un->un_flags = INT_ALIVE;
return (SUCCESS);
}
/*===========================================================================*
* fdopen *
*===========================================================================*/
int
fdopen(struct open_file *f, int ctlr, int unit)
{
FD_UNIT *un;
int *stat;
if (ctlr >= CTLR_MAX)
return (ENXIO);
if (unit >= UNIT_MAX)
return (ENXIO);
un = &fd_unit[ctlr][unit];
stat = un->stat;
if (!(un->un_flags & INT_ALIVE)) {
if (fdinit(un) != SUCCESS)
return (ENXIO);
}
motor_on(ctlr, unit);
fdRecalibrate(ctlr, unit);
fdSenseInt(ctlr, stat);
if (stat[1] != START_CYL) {
printf("fdc%d: unit:%d recalibrate failed. status:0x%x cyl:%d\n",
ctlr, unit, stat[0], stat[1]);
motor_off(ctlr, unit);
return (EIO);
}
if (fd_check(un) != SUCCESS) /* research disk type */
return (EIO);
f->f_devdata = (void *)un;
return (SUCCESS);
}
/*===========================================================================*
* fdclose *
*===========================================================================*/
int
fdclose(struct open_file *f)
{
FD_UNIT *un = f->f_devdata;
fdRecalibrate(un->ctlr, un->unit);
fdSenseInt(un->ctlr, un->stat);
motor_off(un->ctlr, un->unit);
un->un_flags = 0;
return (SUCCESS);
}
/*===========================================================================*
* fdioctl *
*===========================================================================*/
int
fdioctl(struct open_file *f, u_long cmd, void *arg)
{
switch (cmd) {
default:
return (EIO);
}
return (SUCCESS);
}
/*===========================================================================*
* fdstrategy *
*===========================================================================*/
int
fdstrategy(void *devdata, int func, daddr_t blk, size_t size, void *buf,
size_t *rsize)
{
int sectrac, cyl, head, sec;
FD_UNIT *un = devdata;
int ctlr = un->ctlr;
int unit = un->unit;
int *stat = un->stat;
long blknum;
int fd_skip = 0;
u_char *cbuf = (u_char *)buf;
if (un->un_flags & INT_BUSY) {
return (ENXIO);
}
fdDriveStatus(ctlr, unit, 0, stat);
sectrac = un->un_type->seccount; /* sector per track */
*rsize = 0;
while (fd_skip < size) {
blknum = (u_long)blk * DEV_BSIZE/FDBLK + fd_skip/FDBLK;
cyl = blknum / (sectrac * 2);
fdSeek(ctlr, unit, cyl);
fdSenseInt(ctlr, stat);
if (!(stat[0] & RESULT_SEEK)) {
printf("fdc%d: unit:%d seek failed."
"status:0x%x cyl:%d pcyl:%d\n",
ctlr, unit, stat[0], cyl, stat[1]);
goto bad;
}
sec = blknum % (sectrac * 2);
head = sec / sectrac;
sec = sec % sectrac + 1;
if (fdReadWrite(un, func, cyl, head, sec, cbuf) == FAIL) {
printf("fdc%d: unit%d fdReadWrite error [%s]\n",
ctlr, unit, (func==F_READ?"READ":"WRITE"));
goto bad;
}
*rsize += FDBLK;
cbuf += FDBLK;
fd_skip += FDBLK;
}
return (SUCCESS);
bad:
return (FAIL);
}
/*===========================================================================*
* fd_check *
*===========================================================================*/
/*
* this function is Check floppy disk Type
*/
int
fd_check(FD_UNIT *un)
{
int ctlr = un->ctlr;
int unit = un->unit;
int *stat = un->stat;
int type;
static u_char sec_buff[SECTOR_MAX];
un->un_type = (FDDTYPE *)FAIL;
for (type = 0; type < FDTYPE_MAX; type++) {
un->un_type = &fdd_types[type];
/* try read start sector */
outb(FDC_RATE(ctlr), un->un_type->rate); /* rate set */
fdSpecify(ctlr);
fdSeek(ctlr, unit, START_CYL);
fdSenseInt(ctlr, stat);
if (!(stat[0] & RESULT_SEEK) || stat[1] != START_CYL) {
printf("fdc%d: unit:%d seek failed. status:0x%x\n",
ctlr, unit, stat[0]);
goto bad;
}
if (fdReadWrite(un, F_READ,
START_CYL, 0, START_SECTOR, sec_buff) == FAIL) {
continue; /* bad disk type */
}
break;
}
if (un->un_type == (FDDTYPE *)FAIL) {
printf("fdc%d: unit:%d check disk type failed.\n",
ctlr, unit);
goto bad;
}
return (SUCCESS);
bad:
return (FAIL);
}
/*
* for FDC routines.
*/
/*===========================================================================*
* fdc_out *
*===========================================================================*/
int
fdc_out(int ctlr, int cmd)
{
volatile int status;
int time_out;
time_out = TIMEOUT;
while (((status = inb(FDC_STATUS(ctlr))) & (RQM | DIO))
!= (RQM | 0) && time_out-- > 0);
if (time_out <= 0) {
printf("fdc_out: timeout status = 0x%x\n", status);
return (FAIL);
}
outb(FDC_DATA(ctlr), cmd);
return (SUCCESS);
}
/*===========================================================================*
* fdc_in *
*===========================================================================*/
int
fdc_in(int ctlr, u_char *data)
{
volatile int status;
int time_out;
time_out = TIMEOUT;
while ((status = inb(FDC_STATUS(ctlr)) & (RQM | DIO))
!= (RQM | DIO) && time_out-- > 0) {
if (status == RQM) {
printf("fdc_in:error:ready for output\n");
return (FAIL);
}
}
if (time_out <= 0) {
printf("fdc_in:input ready timeout\n");
return (FAIL);
}
if (data) *data = (u_char)inb(FDC_DATA(ctlr));
return (SUCCESS);
}
/*===========================================================================*
* fdc_intr_wait *
*===========================================================================*/
int
fdc_intr_wait(void)
{
return (irq_polling(FDC_IRQ, INT_TIMEOUT)); /* wait interrupt */
}
/*===========================================================================*
* fdc command function *
*===========================================================================*/
void
motor_on(int ctlr, int unit)
{
outb(FDC_DOR(ctlr), DOR_RESET | DOR_DMAEN | unit
| (1 << (unit + 4))); /* reset & unit motor on */
DELAY(1); /* wait 100msec */
}
void
motor_off(int ctlr, int unit)
{
outb(FDC_DOR(ctlr), DOR_RESET); /* reset & motor off */
if (fdc_intr_wait() == FAIL) /* wait interrupt */
printf("fdc: motor off failed.\n");
}
void
fdReset(int ctlr)
{
outb(FDC_DOR(ctlr), 0); /* fdc reset */
DELAY(3);
outb(FDC_DOR(ctlr), DOR_RESET);
DELAY(8);
}
void
fdRecalibrate(int ctlr, int unit)
{
fdc_out(ctlr, CMD_RECALIBRATE);
fdc_out(ctlr, unit);
if (fdc_intr_wait() == FAIL) /* wait interrupt */
printf("fdc: recalibrate Timeout\n");
}
void
fdSpecify(int ctlr)
{
fdc_out(ctlr, CMD_SPECIFY);
fdc_out(ctlr, SPECIFY1);
fdc_out(ctlr, SPECIFY2);
}
void
fdDriveStatus(int ctlr, register int unit, register int head,
register int *stat)
{
u_char result;
fdc_out(ctlr, CMD_DRV_SENSE);
fdc_out(ctlr, (head << 2) | unit);
fdc_in(ctlr, &result);
*stat = (int)(result & 0xff);
}
int
fdSeek(int ctlr, int unit, int cyl)
{
int ret_val = 0;
fdc_out(ctlr, CMD_SEEK);
fdc_out(ctlr, unit);
fdc_out(ctlr, cyl);
if (fdc_intr_wait() == FAIL) { /* wait interrupt */
printf("fdc: fdSeek Timeout\n");
ret_val = FAIL;
}
return(ret_val);
}
int
fdSenseInt(int ctlr, int *stat)
{
u_char result;
fdc_out(ctlr, CMD_SENSE_INT);
fdc_in(ctlr, &result);
*stat++ = (int)(result & 0xff);
fdc_in(ctlr, &result);
*stat++ = (int)(result & 0xff);
return (0);
}
int
fdReadWrite(FD_UNIT *un, int func, int cyl, int head, int sec, u_char *adrs)
{
int i;
int ctlr = un->ctlr;
int unit = un->unit;
int *stat = un->stat;
u_char result;
#if 0
printf("%s:", (func == F_READ ? "READ" : "WRITE"));
printf("cyl = %d", cyl);
printf("head = %d", head);
printf("sec = %d", sec);
printf("secsize = %d", un->un_type->secsize);
printf("seccount = %d", un->un_type->seccount);
printf("gap = %d", un->un_type->gap);
printf("datalen = %d\n", un->un_type->datalen);
#endif
dma_setup(adrs, FDBLK, func, FD_DMA_CHAN);
fdc_out(ctlr, (func == F_READ ? CMD_READ : CMD_WRITE));
fdc_out(ctlr, (head<<2) | unit);
fdc_out(ctlr, cyl); /* cyl */
fdc_out(ctlr, head); /* head */
fdc_out(ctlr, sec); /* sec */
fdc_out(ctlr, un->un_type->secsize); /* secsize */
fdc_out(ctlr, un->un_type->seccount); /* EOT (end of track) */
fdc_out(ctlr, un->un_type->gap); /* GAP3 */
fdc_out(ctlr, un->un_type->datalen); /* DTL (data length) */
if (fdc_intr_wait() == FAIL) { /* wait interrupt */
printf("fdc: DMA transfer Timeout\n");
return (FAIL);
}
for (i = 0; i < 7; i++) {
fdc_in(ctlr, &result);
stat[i] = (int)(result & 0xff);
}
if (stat[0] & ST0_IC_MASK) { /* not normal terminate */
if ((stat[1] & ~ST1_EN) || stat[2])
goto bad;
}
if (!dma_finished(FD_DMA_CHAN)) {
printf("DMA not finished\n");
goto bad;
}
return (SUCCESS);
bad:
printf(" func: %s\n", (func == F_READ ? "F_READ" : "F_WRITE"));
printf(" st0 = 0x%x\n", stat[0]);
printf(" st1 = 0x%x\n", stat[1]);
printf(" st2 = 0x%x\n", stat[2]);
printf(" c = 0x%x\n", stat[3]);
printf(" h = 0x%x\n", stat[4]);
printf(" r = 0x%x\n", stat[5]);
printf(" n = 0x%x\n", stat[6]);
return (FAIL);
}
/*-----------------------------------------------------------------------
* Interrupt Controller Operation Functions
*-----------------------------------------------------------------------
*/
/* 8259A interrupt controller register */
#define INT_CTL0 0x20
#define INT_CTL1 0x21
#define INT2_CTL0 0xA0
#define INT2_CTL1 0xA1
#define CASCADE_IRQ 2
#define ICW1_AT 0x11 /* edge triggered, cascade, need ICW4 */
#define ICW4_AT 0x01 /* not SFNM, not buffered, normal EOI, 8086 */
#define OCW3_PL 0x0e /* polling mode */
#define OCW2_CLEAR 0x20 /* interrupt clear */
/*
* IRC programing sequence
*
* after reset
* 1. ICW1 (write port:INT_CTL0 data:bit4=1)
* 2. ICW2 (write port:INT_CTL1)
* 3. ICW3 (write port:INT_CTL1)
* 4. ICW4 (write port:INT_CTL1)
*
* after ICW
* OCW1 (write port:INT_CTL1)
* OCW2 (write port:INT_CTL0 data:bit3=0,bit4=0)
* OCW3 (write port:INT_CTL0 data:bit3=1,bit4=0)
*
* IMR (read port:INT_CTL1)
* IRR (read port:INT_CTL0) OCW3(bit1=1,bit0=0)
* ISR (read port:INT_CTL0) OCW3(bit1=1,bit0=1)
* PL (read port:INT_CTL0) OCW3(bit2=1,bit1=1)
*/
u_int INT_MASK;
u_int INT2_MASK;
/*===========================================================================*
* irq initialize *
*===========================================================================*/
void
irq_init(void)
{
outb(INT_CTL0, ICW1_AT); /* ICW1 */
outb(INT_CTL1, 0); /* ICW2 for master */
outb(INT_CTL1, (1 << CASCADE_IRQ)); /* ICW3 tells slaves */
outb(INT_CTL1, ICW4_AT); /* ICW4 */
outb(INT_CTL1, (INT_MASK = ~(1 << CASCADE_IRQ)));
/* IRQ mask(exclusive of cascade) */
outb(INT2_CTL0, ICW1_AT); /* ICW1 */
outb(INT2_CTL1, 8); /* ICW2 for slave */
outb(INT2_CTL1, CASCADE_IRQ); /* ICW3 is slave nr */
outb(INT2_CTL1, ICW4_AT); /* ICW4 */
outb(INT2_CTL1, (INT2_MASK = ~0)); /* IRQ 8-15 mask */
}
/*===========================================================================*
* irq polling check *
*===========================================================================*/
int
irq_polling(int irq_no, int timeout)
{
int irc_no;
int data;
int ret;
if (irq_no > 8) irc_no = 1;
else irc_no = 0;
outb(irc_no ? INT2_CTL1 : INT_CTL1, ~(1 << (irq_no >> (irc_no * 3))));
while (--timeout > 0) {
outb(irc_no ? INT2_CTL0 : INT_CTL0, OCW3_PL);
/* set polling mode */
data = inb(irc_no ? INT2_CTL0 : INT_CTL0);
if (data & 0x80) { /* if interrupt request */
if ((irq_no >> (irc_no * 3)) == (data & 0x7)) {
ret = SUCCESS;
break;
}
}
}
if (!timeout) ret = FAIL;
if (irc_no) { /* interrupt clear */
outb(INT2_CTL0, OCW2_CLEAR | (irq_no >> 3));
outb(INT_CTL0, OCW2_CLEAR | CASCADE_IRQ);
} else {
outb(INT_CTL0, OCW2_CLEAR | irq_no);
}
outb(INT_CTL1, INT_MASK);
outb(INT2_CTL1, INT2_MASK);
return (ret);
}
/*---------------------------------------------------------------------------*
* DMA Controller Define *
*---------------------------------------------------------------------------*/
/* DMA Controller Registers */
#define DMA_ADDR 0x004 /* port for low 16 bits of DMA address */
#define DMA_LTOP 0x081 /* port for top low 8bit DMA addr(ch2) */
#define DMA_HTOP 0x481 /* port for top high 8bit DMA addr(ch2) */
#define DMA_COUNT 0x005 /* port for DMA count (count = bytes - 1) */
#define DMA_DEVCON 0x008 /* DMA device control register */
#define DMA_SR 0x008 /* DMA status register */
#define DMA_RESET 0x00D /* DMA software reset register */
#define DMA_FLIPFLOP 0x00C /* DMA byte pointer flip-flop */
#define DMA_MODE 0x00B /* DMA mode port */
#define DMA_INIT 0x00A /* DMA init port */
#define DMA_RESET_VAL 0x06
/* DMA channel commands. */
#define DMA_READ 0x46 /* DMA read opcode */
#define DMA_WRITE 0x4A /* DMA write opcode */
/*===========================================================================*
* dma_setup *
*===========================================================================*/
void
dma_setup(u_char *buf, int size, int func, int chan)
{
u_long pbuf = local_to_PCI((u_long)buf);
#if 0
outb(DMA_RESET, 0);
DELAY(1);
outb(DMA_DEVCON, 0x00);
outb(DMA_INIT, DMA_RESET_VAL); /* reset the dma controller */
#endif
outb(DMA_MODE, func == F_READ ? DMA_READ : DMA_WRITE);
outb(DMA_FLIPFLOP, 0); /* write anything to reset it */
outb(DMA_ADDR, (int)pbuf >> 0);
outb(DMA_ADDR, (int)pbuf >> 8);
outb(DMA_LTOP, (int)pbuf >> 16);
outb(DMA_HTOP, (int)pbuf >> 24);
outb(DMA_COUNT, (size - 1) >> 0);
outb(DMA_COUNT, (size - 1) >> 8);
outb(DMA_INIT, chan); /* some sort of enable */
}
int
dma_finished(int chan)
{
return ((inb(DMA_SR) & 0x0f) == (1 << chan));
}