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- more accurate timing for reading data using a motor speed of 300 RPM. This is

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important at boot time if the user wants to control the boot process.
  TODO:
  * implement timing for write and format commands
  * more accurate timing for seek, recalibrate and maybe others
  * raw floppy access slows down the emulation, use separate threads (???)
- irq line goes low with when reading the first result byte
- the drive status bits are only modified after reading the first result byte
- handling of floppy command 'sense interrupt status' simplified
- improved debug messages for i/o port reads and writes
This commit is contained in:
Volker Ruppert 2005-08-31 19:48:03 +00:00
parent 086ee4c9aa
commit b88facfb66
1 changed files with 62 additions and 65 deletions
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127
bochs/iodev/floppy.cc
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@ -1,5 +1,5 @@
/////////////////////////////////////////////////////////////////////////
// $Id: floppy.cc,v 1.79 2005-08-24 20:44:55 vruppert Exp $
// $Id: floppy.cc,v 1.80 2005-08-31 19:48:03 vruppert Exp $
/////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2002 MandrakeSoft S.A.
@ -132,7 +132,7 @@ bx_floppy_ctrl_c::init(void)
{
Bit8u i;
BX_DEBUG(("Init $Id: floppy.cc,v 1.79 2005-08-24 20:44:55 vruppert Exp $"));
BX_DEBUG(("Init $Id: floppy.cc,v 1.80 2005-08-31 19:48:03 vruppert Exp $"));
DEV_dma_register_8bit_channel(2, dma_read, dma_write, "Floppy Drive");
DEV_register_irq(6, "Floppy Drive");
for (unsigned addr=0x03F2; addr<=0x03F7; addr++) {
@ -374,38 +374,31 @@ bx_floppy_ctrl_c::read(Bit32u address, unsigned io_len)
#else
UNUSED(this_ptr);
#endif // !BX_USE_FD_SMF
Bit8u value, drive;
if (bx_dbg.floppy)
BX_INFO(("read access to port %04x", (unsigned) address));
Bit8u value = 0, drive;
switch (address) {
#if BX_DMA_FLOPPY_IO
case 0x3F2: // diskette controller digital output register
value = BX_FD_THIS s.DOR;
return(value);
break;
case 0x3F4: /* diskette controller main status register */
value = BX_FD_THIS s.main_status_reg;
return(value);
break;
case 0x3F5: /* diskette controller data */
if (BX_FD_THIS s.result_size == 0) {
BX_ERROR(("port 0x3f5: no results to read"));
BX_FD_THIS s.main_status_reg = 0;
return BX_FD_THIS s.result[0];
value = BX_FD_THIS s.result[0];
} else {
value = BX_FD_THIS s.result[BX_FD_THIS s.result_index++];
BX_FD_THIS s.main_status_reg &= 0xF0;
BX_FD_THIS lower_interrupt();
if (BX_FD_THIS s.result_index >= BX_FD_THIS s.result_size) {
enter_idle_phase();
}
value = BX_FD_THIS s.result[BX_FD_THIS s.result_index++];
BX_FD_THIS s.main_status_reg &= 0xF0;
if (BX_FD_THIS s.result_index >= BX_FD_THIS s.result_size) {
if (!BX_FD_THIS s.reset_sensei) BX_FD_THIS s.pending_irq = 0;
DEV_pic_lower_irq(6);
enter_idle_phase();
}
return(value);
}
break;
#endif // #if BX_DMA_FLOPPY_IO
@ -432,17 +425,15 @@ bx_floppy_ctrl_c::read(Bit32u address, unsigned io_len)
default: // BX_FLOPPY_NONE
value = 0x20;
break;
}
}
else {
} else {
value = 0x20;
}
return( value );
}
break;
case 0x3F6: // Reserved for future floppy controllers
// This address shared with the hard drive controller
value = DEV_hd_read_handler(bx_devices.pluginHardDrive, address, io_len);
return( value );
break;
case 0x3F7: // diskette controller digital input register
@ -453,13 +444,15 @@ bx_floppy_ctrl_c::read(Bit32u address, unsigned io_len)
value &= 0x7f;
// add in diskette change line
value |= (BX_FD_THIS s.DIR[BX_FD_THIS s.DOR & 0x03] & 0x80);
return( value );
break;
default:
BX_ERROR(("io_read: unsupported address 0x%04x", (unsigned) address));
return(0);
break;
}
}
BX_DEBUG(("read access to port %04x returns 0x%02x", address, value));
return (value);
}
@ -487,9 +480,7 @@ bx_floppy_ctrl_c::write(Bit32u address, Bit32u value, unsigned io_len)
Bit8u drive_select;
Bit8u motor_on_drive0, motor_on_drive1;
if (bx_dbg.floppy)
BX_INFO(("write access to port %04x, value=%02x",
(unsigned) address, (unsigned) value));
BX_DEBUG(("write access to port %04x, value=%02x", address, value));
switch (address) {
#if BX_DMA_FLOPPY_IO
@ -553,7 +544,8 @@ bx_floppy_ctrl_c::write(Bit32u address, Bit32u value, unsigned io_len)
BX_FD_THIS s.command_complete = 0;
BX_FD_THIS s.command_index = 1;
/* read/write command in progress */
BX_FD_THIS s.main_status_reg = FD_MS_MRQ | FD_MS_BUSY;
BX_FD_THIS s.main_status_reg &= 0x0f; // leave drive status untouched
BX_FD_THIS s.main_status_reg |= FD_MS_MRQ | FD_MS_BUSY;
switch (value) {
case 0x03: /* specify */
BX_FD_THIS s.command_size = 3;
@ -670,7 +662,7 @@ bx_floppy_ctrl_c::floppy_command(void)
Bit8u motor_on;
Bit8u head, drive, cylinder, sector, eot;
Bit8u sector_size, data_length;
Bit32u logical_sector;
Bit32u logical_sector, sector_time;
// Print command
char buf[9+(9*5)+1], *p = buf;
@ -746,19 +738,14 @@ bx_floppy_ctrl_c::floppy_command(void)
* byte0 = status reg0
* byte1 = current cylinder number (0 to 79)
*/
drive = BX_FD_THIS s.DOR & 0x03;
if (!BX_FD_THIS s.pending_irq) {
if (BX_FD_THIS s.reset_sensei > 0) {
drive = 4 - BX_FD_THIS s.reset_sensei;
BX_FD_THIS s.status_reg0 &= 0xf8;
BX_FD_THIS s.status_reg0 |= (BX_FD_THIS s.head[drive] << 2) | drive;
BX_FD_THIS s.reset_sensei--;
} else if (!BX_FD_THIS s.pending_irq) {
BX_FD_THIS s.status_reg0 = 0x80;
}
else {
if (BX_FD_THIS s.reset_sensei > 0) {
drive = 4 - BX_FD_THIS s.reset_sensei;
BX_FD_THIS s.status_reg0 &= 0xf8;
BX_FD_THIS s.status_reg0 |= (BX_FD_THIS s.head[drive] << 2) | drive;
BX_FD_THIS s.reset_sensei--;
}
}
}
BX_DEBUG(("sense interrupt status"));
enter_result_phase();
return;
@ -971,31 +958,26 @@ bx_floppy_ctrl_c::floppy_command(void)
if ((BX_FD_THIS s.command[0] & 0x4f) == 0x46) { // read
floppy_xfer(drive, logical_sector*512, BX_FD_THIS s.floppy_buffer,
512, FROM_FLOPPY);
DEV_dma_set_drq(FLOPPY_DMA_CHAN, 1);
/* data reg not ready, controller busy */
BX_FD_THIS s.main_status_reg = FD_MS_BUSY;
return;
}
else if ((BX_FD_THIS s.command[0] & 0x7f) == 0x45) { // write
DEV_dma_set_drq(FLOPPY_DMA_CHAN, 1);
// time to read one sector at 300 rpm
sector_time = 200000 / BX_FD_THIS s.media[drive].sectors_per_track;
bx_pc_system.activate_timer(BX_FD_THIS s.floppy_timer_index,
sector_time , 0);
} else if ((BX_FD_THIS s.command[0] & 0x7f) == 0x45) { // write
/* data reg not ready, controller busy */
BX_FD_THIS s.main_status_reg = FD_MS_BUSY;
return;
}
else
DEV_dma_set_drq(FLOPPY_DMA_CHAN, 1);
} else {
BX_PANIC(("floppy_command(): unknown read/write command"));
return;
return;
}
break;
default: // invalid or unsupported command; these are captured in write() above
BX_PANIC(("You should never get here! cmd = 0x%02x",
BX_FD_THIS s.command[0]));
}
}
#endif
}
@ -1143,6 +1125,14 @@ bx_floppy_ctrl_c::timer()
enter_result_phase();
break;
case 0x46: // read normal data
case 0x66:
case 0xc6:
case 0xe6:
// transfer next sector
DEV_dma_set_drq(FLOPPY_DMA_CHAN, 1);
break;
case 0xfe: // (contrived) RESET
theFloppyController->reset(BX_RESET_SOFTWARE);
BX_FD_THIS s.pending_command = 0;
@ -1189,13 +1179,12 @@ bx_floppy_ctrl_c::dma_write(Bit8u *data_byte)
BX_INFO((" head = %u", (unsigned) BX_FD_THIS s.head[drive]));
BX_INFO((" cylinder = %u", (unsigned) BX_FD_THIS s.cylinder[drive]));
BX_INFO((" sector = %u", (unsigned) BX_FD_THIS s.sector[drive]));
}
}
DEV_dma_set_drq(FLOPPY_DMA_CHAN, 0);
enter_result_phase();
}
else { // more data to transfer
Bit32u logical_sector;
} else { // more data to transfer
Bit32u logical_sector, sector_time;
// original assumed all floppies had two sides...now it does not *delete this comment line*
logical_sector = (BX_FD_THIS s.cylinder[drive] * BX_FD_THIS s.media[drive].heads *
@ -1206,8 +1195,13 @@ bx_floppy_ctrl_c::dma_write(Bit8u *data_byte)
floppy_xfer(drive, logical_sector*512, BX_FD_THIS s.floppy_buffer,
512, FROM_FLOPPY);
}
DEV_dma_set_drq(FLOPPY_DMA_CHAN, 0);
// time to read one sector at 300 rpm
sector_time = 200000 / BX_FD_THIS s.media[drive].sectors_per_track;
bx_pc_system.activate_timer(BX_FD_THIS s.floppy_timer_index,
sector_time , 0);
}
}
}
void
@ -1315,8 +1309,10 @@ bx_floppy_ctrl_c::raise_interrupt(void)
void
bx_floppy_ctrl_c::lower_interrupt(void)
{
DEV_pic_lower_irq(6);
BX_FD_THIS s.pending_irq = 0;
if (BX_FD_THIS s.pending_irq) {
DEV_pic_lower_irq(6);
BX_FD_THIS s.pending_irq = 0;
}
}
@ -1693,7 +1689,8 @@ bx_floppy_ctrl_c::enter_result_phase(void)
/* these are always the same */
BX_FD_THIS s.result_index = 0;
BX_FD_THIS s.main_status_reg = FD_MS_MRQ | FD_MS_DIO | FD_MS_BUSY;
BX_FD_THIS s.main_status_reg &= 0x0f; // leave drive status untouched
BX_FD_THIS s.main_status_reg |= FD_MS_MRQ | FD_MS_DIO | FD_MS_BUSY;
/* invalid command */
if ((BX_FD_THIS s.status_reg0 & 0xc0) == 0x80) {