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FDC changes :

Browse source 
- Seperated disk and disk drive emulation
- Support more drive types - 5.25" dual RPM, 3.5" DD, 3.5" HD, 3.5" HD 3-Mode
- Support drive swapping (FDC37c665 only)
- Support FDC FIFO
- Support other FDC 'enhanced mode' behaviour
- Support IBM XDF format images
- Formatting now formats both tracks, and uses correct 'fill' byte
- Various other improvements

Many of these changes provided by Battler
This commit is contained in:
TomW 2015-12-12 16:31:08 +00:00
commit eebdc165b2
16 changed files with 1530 additions and 340 deletions
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457
src/fdc.c
View file

@ -4,6 +4,7 @@
#include "disc.h"
#include "dma.h"
#include "fdd.h"
#include "io.h"
#include "pic.h"
#include "timer.h"
@ -16,6 +17,7 @@ typedef struct FDC
{
uint8_t dor,stat,command,dat,st0;
int head,track[256],sector,drive,lastdrive;
int rw_track;
int pos;
uint8_t params[256];
uint8_t res[256];
@ -42,6 +44,22 @@ typedef struct FDC
int dskchg_activelow;
int enable_3f1;
int bitcell_period;
int is_nsc; /* 1 = FDC is on a National Semiconductor Super I/O chip, 0 = other FDC. This is needed,
because the National Semiconductor Super I/O chips add some FDC commands. */
int enh_mode;
int rwc[2];
int boot_drive;
int densel_polarity;
int densel_force;
int drvrate[2];
int dma;
int fifo, tfifo;
int fifobufpos;
uint8_t fifobuf[16];
} FDC;
static FDC fdc;
@ -65,11 +83,59 @@ void fdc_reset()
fdc.head = 0;
fdc.abort = 0;
if (!AT)
fdc.rate=2;
{
fdc.rate = 2;
// fdc_update_rate();
}
// pclog("Reset FDC\n");
}
int ins;
void fdc_reset_fifo_buf()
{
int i = 0;
memset(fdc.fifobuf, 0, 16);
fdc.fifobufpos = 0;
}
void fdc_fifo_buf_write(int val)
{
if (fdc.fifobufpos < fdc.tfifo)
{
fdc.fifobuf[fdc.fifobufpos] = val;
fdc.fifobufpos++;
fdc.fifobufpos %= fdc.tfifo;
// pclog("FIFO buffer position = %02X\n", fdc.fifobufpos);
if (fdc.fifobufpos == fdc.tfifo) fdc.fifobufpos = 0;
}
}
int fdc_fifo_buf_read()
{
int temp = 0;
if (fdc.fifobufpos < fdc.tfifo)
{
temp = fdc.fifobuf[fdc.fifobufpos];
fdc.fifobufpos++;
fdc.fifobufpos %= fdc.tfifo;
// pclog("FIFO buffer position = %02X\n", fdc.fifobufpos);
if (fdc.fifobufpos == fdc.tfifo) fdc.fifobufpos = 0;
}
return temp;
}
/* For DMA mode, just goes ahead in FIFO buffer but doesn't actually read or write anything. */
void fdc_fifo_buf_dummy()
{
if (fdc.fifobufpos < fdc.tfifo)
{
fdc.fifobufpos++;
fdc.fifobufpos %= fdc.tfifo;
// pclog("FIFO buffer position = %02X\n", fdc.fifobufpos);
if (fdc.fifobufpos == fdc.tfifo) fdc.fifobufpos = 0;
}
}
static void fdc_int()
{
if (!fdc.pcjr)
@ -93,9 +159,164 @@ static void fdc_watchdog_poll(void *p)
}
}
/* fdc.rwc per Winbond W83877F datasheet:
0 = normal;
1 = 500 kbps, 360 rpm;
2 = 500 kbps, 300 rpm;
3 = 250 kbps
Drive is only aware of selected rate and densel, so on real hardware, the rate expected by FDC and the rate actually being
processed by drive can mismatch, in which case the FDC won't receive the correct data.
*/
int bit_rate = 250;
void fdc_update_is_nsc(int is_nsc)
{
fdc.is_nsc = is_nsc;
}
void fdc_update_enh_mode(int enh_mode)
{
fdc.enh_mode = enh_mode;
}
int fdc_get_rwc(int drive)
{
return fdc.rwc[drive];
}
void fdc_update_rwc(int drive, int rwc)
{
fdc.rwc[drive] = rwc;
}
int fdc_get_boot_drive()
{
return fdc.boot_drive;
}
void fdc_update_boot_drive(int boot_drive)
{
fdc.boot_drive = boot_drive;
}
void fdc_update_densel_polarity(int densel_polarity)
{
fdc.densel_polarity = densel_polarity;
}
void fdc_update_densel_force(int densel_force)
{
fdc.densel_force = densel_force;
}
void fdc_update_drvrate(int drive, int drvrate)
{
fdc.drvrate[drive] = drvrate;
}
void fdc_update_rate(int drive)
{
if ((fdc.rwc[drive] == 1) || (fdc.rwc[drive] == 2))
{
bit_rate = 500;
}
else if (fdc.rwc[drive] == 3)
{
bit_rate = 250;
}
else switch (fdc.rate)
{
case 0: /*High density*/
bit_rate = 500;
break;
case 1: /*Double density (360 rpm)*/
switch(fdc.drvrate[drive])
{
case 0:
bit_rate = 300;
break;
case 1:
bit_rate = 500;
break;
case 2:
bit_rate = 2000;
break;
}
break;
case 2: /*Double density*/
bit_rate = 250;
break;
case 3: /*Extended density*/
bit_rate = 1000;
break;
}
fdc.bitcell_period = 1000000 / bit_rate*2; /*Bitcell period in ns*/
// pclog("fdc_update_rate: rate=%i bit_rate=%i bitcell_period=%i\n", fdc.rate, bit_rate, fdc.bitcell_period);
}
int fdc_get_bitcell_period()
{
return fdc.bitcell_period;
}
static int fdc_get_densel(int drive)
{
switch (fdc.rwc[drive])
{
case 1:
case 3:
return 0;
case 2:
return 1;
}
if (!fdc.is_nsc)
{
switch (fdc.densel_force)
{
case 2:
return 1;
case 3:
return 0;
}
}
else
{
switch (fdc.densel_force)
{
case 0:
return 0;
case 1:
return 1;
}
}
switch (fdc.rate)
{
case 0:
case 3:
return fdc.densel_polarity ? 1 : 0;
case 1:
case 2:
return fdc.densel_polarity ? 0 : 1;
}
}
static void fdc_rate(int drive)
{
fdc_update_rate(drive);
disc_set_rate(drive, fdc.drvrate[drive], fdc.rate);
fdd_set_densel(fdc_get_densel(drive));
}
void fdc_write(uint16_t addr, uint8_t val, void *priv)
{
// pclog("Write FDC %04X %02X %04X:%04X %i %02X %i rate=%i %i\n",addr,val,cs>>4,pc,ins,fdc.st0,ins,fdc.rate, fdc.data_ready);
int drive;
switch (addr&7)
{
case 1: return;
@ -149,6 +370,14 @@ void fdc_write(uint16_t addr, uint8_t val, void *priv)
fdc.dor=val;
// printf("DOR now %02X\n",val);
return;
case 3:
/* TDR */
if (fdc.enh_mode)
{
drive = (fdc.dor & 1) ^ fdd_swap;
fdc.rwc[drive] = (val & 0x30) >> 4;
}
return;
case 4:
if (val & 0x80)
{
@ -162,8 +391,16 @@ void fdc_write(uint16_t addr, uint8_t val, void *priv)
case 5: /*Command register*/
if ((fdc.stat & 0xf0) == 0xb0)
{
fdc.dat = val;
fdc.stat &= ~0x80;
if (fdc.pcjr || !fdc.fifo)
{
fdc.dat = val;
fdc.stat &= ~0x80;
}
else
{
fdc_fifo_buf_write(val);
if (fdc.fifobufpos == 0) fdc.stat &= ~0x80;
}
break;
}
// if (fdc.inread)
@ -178,6 +415,15 @@ void fdc_write(uint16_t addr, uint8_t val, void *priv)
// pclog("Starting FDC command %02X\n",fdc.command);
switch (fdc.command&0x1F)
{
case 1: /*Mode*/
if (!fdc.is_nsc) goto bad_command;
fdc.pnum=0;
fdc.ptot=4;
fdc.stat=0x90;
fdc.pos=0;
fdc.format_state = 0;
break;
case 2: /*Read track*/
fdc.pnum=0;
fdc.ptot=8;
@ -273,13 +519,19 @@ void fdc_write(uint16_t addr, uint8_t val, void *priv)
break;
case 0x18:
fdc.stat = 0x10;
discint = 0xfc;
if (!fdc.is_nsc) goto bad_command;
fdc.lastdrive = fdc.drive;
discint = 0x10;
fdc.pos = 0;
fdc_callback();
/* fdc.stat = 0x10;
discint = 0xfc;
fdc_callback(); */
break;
default:
fatal("Bad FDC command %02X\n",val);
bad_command:
// fatal("Bad FDC command %02X\n",val);
// dumpregs();
// exit(-1);
fdc.stat=0x10;
@ -304,31 +556,35 @@ void fdc_write(uint16_t addr, uint8_t val, void *priv)
// fdc.drive = fdc.params[0] & 3;
disc_drivesel = fdc.drive & 1;
fdc_reset_stat = 0;
disc_set_drivesel(fdc.drive & 1);
switch (discint)
{
case 2: /*Read a track*/
fdc.track[fdc.drive]=fdc.params[1];
fdc_rate(fdc.drive);
fdc.head=fdc.params[2];
fdc.sector=fdc.params[3];
fdc.eot[fdc.drive] = fdc.params[5];
if (fdc.config & 0x40)
disc_seek(fdc.drive, fdc.track[fdc.drive]);
fdd_seek(fdc.drive, fdc.params[1] - fdc.track[fdc.drive]);
fdc.track[fdc.drive]=fdc.params[1];
// pclog("Read a track track=%i head=%i sector=%i eot=%i\n", fdc.track[fdc.drive], fdc.head, fdc.sector, fdc.eot[fdc.drive]);
disc_readsector(fdc.drive, SECTOR_FIRST, fdc.track[fdc.drive], fdc.head, fdc.rate);
disc_readsector(fdc.drive, SECTOR_FIRST, fdc.track[fdc.drive], fdc.head, fdc.rate, fdc.params[4]);
disctime = 0;
readflash = 1;
fdc.inread = 1;
break;
case 5: /*Write data*/
fdc.track[fdc.drive]=fdc.params[1];
fdc_rate(fdc.drive);
fdc.head=fdc.params[2];
fdc.sector=fdc.params[3];
fdc.eot[fdc.drive] = fdc.params[4];
fdc.eot[fdc.drive] = fdc.params[5];
if (fdc.config & 0x40)
disc_seek(fdc.drive, fdc.track[fdc.drive]);
disc_writesector(fdc.drive, fdc.sector, fdc.track[fdc.drive], fdc.head, fdc.rate);
fdd_seek(fdc.drive, fdc.params[1] - fdc.track[fdc.drive]);
fdc.track[fdc.drive]=fdc.params[1];
fdc.rw_track = fdc.params[1];
disc_writesector(fdc.drive, fdc.sector, fdc.track[fdc.drive], fdc.head, fdc.rate, fdc.params[4]);
disctime = 0;
fdc.written = 0;
readflash = 1;
@ -339,14 +595,16 @@ void fdc_write(uint16_t addr, uint8_t val, void *priv)
break;
case 6: /*Read data*/
fdc.track[fdc.drive]=fdc.params[1];
fdc_rate(fdc.drive);
fdc.head=fdc.params[2];
fdc.sector=fdc.params[3];
fdc.eot[fdc.drive] = fdc.params[4];
fdc.eot[fdc.drive] = fdc.params[5];
if (fdc.config & 0x40)
disc_seek(fdc.drive, fdc.track[fdc.drive]);
disc_readsector(fdc.drive, fdc.sector, fdc.track[fdc.drive], fdc.head, fdc.rate);
fdd_seek(fdc.drive, fdc.params[1] - fdc.track[fdc.drive]);
fdc.track[fdc.drive]=fdc.params[1];
fdc.rw_track = fdc.params[1];
disc_readsector(fdc.drive, fdc.sector, fdc.track[fdc.drive], fdc.head, fdc.rate, fdc.params[4]);
disctime = 0;
readflash = 1;
fdc.inread = 1;
@ -355,10 +613,12 @@ void fdc_write(uint16_t addr, uint8_t val, void *priv)
case 7: /*Recalibrate*/
fdc.stat = 1 << fdc.drive;
disctime = 0;
disc_seek(fdc.drive, 0);
fdd_seek(fdc.drive, SEEK_RECALIBRATE);
break;
case 0x0d: /*Format*/
fdc_rate(fdc.drive);
fdc.head = (fdc.params[0] & 4) ? 1 : 0;
fdc.format_state = 1;
fdc.pos = 0;
fdc.stat = 0x30;
@ -368,13 +628,15 @@ void fdc_write(uint16_t addr, uint8_t val, void *priv)
fdc.stat = 1 << fdc.drive;
fdc.head = (fdc.params[0] & 4) ? 1 : 0;
disctime = 0;
disc_seek(fdc.drive, fdc.params[1]);
fdd_seek(fdc.drive, fdc.params[1] - fdc.track[fdc.drive]);
// pclog("Seek to %i\n", fdc.params[1]);
break;
case 10: /*Read sector ID*/
fdc_rate(fdc.drive);
disctime = 0;
fdc.head = (fdc.params[0] & 4) ? 1 : 0;
// rpclog("Read sector ID %i %i\n", fdc.rate, fdc.drive);
// pclog("Read sector ID %i %i\n", fdc.rate, fdc.drive);
disc_readaddress(fdc.drive, fdc.track[fdc.drive], fdc.head, fdc.rate);
break;
}
@ -384,7 +646,6 @@ void fdc_write(uint16_t addr, uint8_t val, void *priv)
case 7:
if (!AT) return;
fdc.rate=val&3;
disc_set_rate(fdc.rate);
disc_3f7=val;
return;
@ -398,21 +659,28 @@ int paramstogo=0;
uint8_t fdc_read(uint16_t addr, void *priv)
{
uint8_t temp;
int drive;
// /*if (addr!=0x3f4) */printf("Read FDC %04X %04X:%04X %04X %i %02X %02x %i ",addr,cs>>4,pc,BX,fdc.pos,fdc.st0,fdc.stat,ins);
switch (addr&7)
{
case 1: /*???*/
drive = (fdc.dor & 1) ^ fdd_swap;
if (!fdc.enable_3f1)
return 0xff;
// temp=0x50;
temp = 0x70;
if (fdc.dor & 1)
if (drive)
temp &= ~0x40;
else
temp &= ~0x20;
break;
case 3:
temp = 0x20;
if (!fdc.enh_mode)
temp = 0x20;
else
{
temp = fdc.rwc[drive] << 4;
}
break;
case 4: /*Status*/
temp=fdc.stat;
@ -421,7 +689,12 @@ uint8_t fdc_read(uint16_t addr, void *priv)
fdc.stat&=~0x80;
if ((fdc.stat & 0xf0) == 0xf0)
{
temp = fdc.dat;
if (fdc.pcjr || !fdc.fifo)
temp = fdc.dat;
else
{
temp = fdc_fifo_buf_read();
}
break;
}
if (paramstogo)
@ -457,8 +730,9 @@ uint8_t fdc_read(uint16_t addr, void *priv)
fdc.stat &= 0xf0;
break;
case 7: /*Disk change*/
if (fdc.dor & (0x10 << (fdc.dor & 1)))
temp = (disc_changed[fdc.drive] || drive_empty[fdc.drive]) ? 0x80 : 0;
drive = (fdc.dor & 1) ^ fdd_swap;
if (fdc.dor & (0x10 << drive))
temp = (disc_changed[drive] || drive_empty[drive])?0x80:0;
else
temp = 0;
if (fdc.dskchg_activelow) /*PC2086/3086 seem to reverse this bit*/
@ -497,6 +771,11 @@ void fdc_callback()
fdc_int();
fdc_reset_stat = 4;
return;
case 1: /*Mode*/
fdc.stat=0x80;
fdc.densel_force = (fdc.params[2] & 0xC0) >> 6;
return;
case 2: /*Read track*/
readflash = 1;
fdc.eot[fdc.drive]--;
@ -518,17 +797,18 @@ void fdc_callback()
return;
}
else
disc_readsector(fdc.drive, SECTOR_NEXT, fdc.track[fdc.drive], fdc.head, fdc.rate);
disc_readsector(fdc.drive, SECTOR_NEXT, fdc.track[fdc.drive], fdc.head, fdc.rate, fdc.params[4]);
fdc.inread = 1;
return;
case 3: /*Specify*/
fdc.stat=0x80;
fdc.specify[0] = fdc.params[0];
fdc.specify[1] = fdc.params[1];
fdc.dma = (fdc.specify[1] & 1) ^ 1;
return;
case 4: /*Sense drive status*/
fdc.res[10] = (fdc.params[0] & 7) | 0x28;
if (!fdc.track[fdc.drive])
if (fdd_track0(fdc.drive))
fdc.res[10] |= 0x10;
if (writeprot[fdc.drive])
fdc.res[10] |= 0x40;
@ -549,7 +829,8 @@ void fdc_callback()
fdc.head ^= 1;
if (!fdc.head)
{
fdc.track[fdc.drive]++;
fdc.rw_track++;
// fdc.track[fdc.drive]++;
/* if (fdc.track[fdc.drive] >= 79)
{
fdc.track[fdc.drive] = 79;
@ -559,7 +840,8 @@ void fdc_callback()
}
else
{
fdc.track[fdc.drive]++;
fdc.rw_track++;
// fdc.track[fdc.drive]++;
fdc.tc = 1;
}
}
@ -570,14 +852,14 @@ void fdc_callback()
fdc.stat=0xD0;
fdc.res[4]=(fdc.head?4:0)|fdc.drive;
fdc.res[5]=fdc.res[6]=0;
fdc.res[7]=fdc.track[fdc.drive];
fdc.res[7]=fdc.rw_track;
fdc.res[8]=fdc.head;
fdc.res[9]=fdc.sector;
fdc.res[10]=fdc.params[4];
paramstogo=7;
return;
}
disc_writesector(fdc.drive, fdc.sector, fdc.track[fdc.drive], fdc.head, fdc.rate);
disc_writesector(fdc.drive, fdc.sector, fdc.rw_track, fdc.head, fdc.rate, fdc.params[4]);
// ioc_fiq(IOC_FIQ_DISC_DATA);
return;
case 6: /*Read data*/
@ -592,7 +874,8 @@ void fdc_callback()
fdc.head ^= 1;
if (!fdc.head)
{
fdc.track[fdc.drive]++;
fdc.rw_track++;
// fdc.track[fdc.drive]++;
/* if (fdc.track[fdc.drive] >= 79)
{
fdc.track[fdc.drive] = 79;
@ -602,7 +885,8 @@ void fdc_callback()
}
else
{
fdc.track[fdc.drive]++;
fdc.rw_track++;
// fdc.track[fdc.drive]++;
fdc.tc = 1;
}
}
@ -614,14 +898,14 @@ void fdc_callback()
fdc.stat=0xD0;
fdc.res[4]=(fdc.head?4:0)|fdc.drive;
fdc.res[5]=fdc.res[6]=0;
fdc.res[7]=fdc.track[fdc.drive];
fdc.res[7]=fdc.rw_track;
fdc.res[8]=fdc.head;
fdc.res[9]=fdc.sector;
fdc.res[10]=fdc.params[4];
paramstogo=7;
return;
}
disc_readsector(fdc.drive, fdc.sector, fdc.track[fdc.drive], fdc.head, fdc.rate);
disc_readsector(fdc.drive, fdc.sector, fdc.rw_track, fdc.head, fdc.rate, fdc.params[4]);
fdc.inread = 1;
return;
@ -686,10 +970,10 @@ void fdc_callback()
disctime = 128 * (1 << TIMER_SHIFT);
timer_update_outstanding();
}
else if (fdc.format_state == 4)
else if (fdc.format_state == 3)
{
// rpclog("Format next stage\n");
disc_format(fdc.drive, fdc.track[fdc.drive], fdc.head, fdc.rate);
// pclog("Format next stage track %i head %i\n", fdc.track[fdc.drive], fdc.head);
disc_format(fdc.drive, fdc.track[fdc.drive], fdc.head, fdc.rate, fdc.params[4]);
fdc.format_state = 4;
}
else
@ -756,6 +1040,9 @@ void fdc_callback()
case 0x13: /*Configure*/
fdc.config = fdc.params[1];
fdc.pretrk = fdc.params[2];
fdc.fifo = (fdc.params[1] & 0x20) ? 0 : 1;
fdc.tfifo = (fdc.params[1] & 0xF) + 1;
pclog("FIFO is now %02X, threshold is %02X\n", fdc.fifo, fdc.tfifo);
fdc.stat = 0x80;
disctime = 0;
// picint(0x40);
@ -777,6 +1064,13 @@ void fdc_callback()
disctime = 0;
return;
case 0x18: /*NSC*/
fdc.stat = (fdc.stat & 0xf) | 0xd0;
fdc.res[10] = 0x73;
paramstogo=1;
discint=0;
disctime = 0;
return;
case 0xfc: /*Invalid*/
fdc.dat = fdc.st0 = 0x80;
@ -797,7 +1091,7 @@ void fdc_callback()
void fdc_overrun()
{
img_stop();
disc_sector_stop();
disctime = 0;
fdc_int();
@ -817,7 +1111,7 @@ int fdc_data(uint8_t data)
if (fdc.tc)
return 0;
if (fdc.pcjr)
if (fdc.pcjr || !fdc.dma)
{
if (fdc.data_ready)
{
@ -826,15 +1120,44 @@ int fdc_data(uint8_t data)
return -1;
}
fdc.dat = data;
fdc.data_ready = 1;
fdc.stat = 0xf0;
// pclog("fdc_data\n");
if (fdc.pcjr || !fdc.fifo)
{
fdc.dat = data;
fdc.data_ready = 1;
fdc.stat = 0xf0;
}
else
{
// FIFO enabled
fdc_fifo_buf_write(data);
if (fdc.fifobufpos == 0)
{
// We have wrapped around, means FIFO is over
fdc.data_ready = 1;
fdc.stat = 0xf0;
}
}
}
else
{
if (dma_channel_write(2, data) & DMA_OVER)
fdc.tc = 1;
if (!fdc.fifo)
{
fdc.data_ready = 1;
fdc.stat = 0xd0;
}
else
{
fdc_fifo_buf_dummy();
if (fdc.fifobufpos == 0)
{
// We have wrapped around, means FIFO is over
fdc.data_ready = 1;
fdc.stat = 0xd0;
}
}
}
return 0;
@ -918,7 +1241,7 @@ int fdc_getdata(int last)
{
int data;
if (fdc.pcjr)
if (fdc.pcjr || !fdc.dma)
{
if (fdc.written)
{
@ -926,13 +1249,37 @@ int fdc_getdata(int last)
// pclog("Overrun\n");
return -1;
}
data = fdc.dat;
if (!last)
fdc.stat = 0xb0;
if (fdc.pcjr || !fdc.fifo)
{
data = fdc.dat;
if (!last)
fdc.stat = 0xb0;
}
else
{
data = fdc_fifo_buf_read();
if (!last && (fdc.fifobufpos == 0))
fdc.stat = 0xb0;
}
}
else
{
data = dma_channel_read(2);
if (!fdc.fifo)
{
if (!last)
fdc.stat = 0x90;
}
else
{
fdc_fifo_buf_dummy();
if (!last && (fdc.fifobufpos == 0))
fdc.stat = 0x90;
}
if (data & DMA_OVER)
fdc.tc = 1;
@ -968,6 +1315,14 @@ void fdc_init()
timer_add(fdc_callback, &disctime, &disctime, NULL);
fdc.dskchg_activelow = 0;
fdc.enable_3f1 = 1;
fdc_update_enh_mode(0);
fdc_update_densel_polarity(1);
fdc_update_rwc(0, 0);
fdc_update_rwc(1, 0);
fdc_update_densel_force(0);
fdc.fifo = fdc.tfifo = 0;
}
void fdc_add()