blob: 5313b96607b5695322e6f169e9b01f3a0d755c8c [file] [log] [blame]
// 16bit code to access floppy drives.
//
// Copyright (C) 2008 Kevin O'Connor <kevin@koconnor.net>
// Copyright (C) 2002 MandrakeSoft S.A.
//
// This file may be distributed under the terms of the GNU GPLv3 license.
#include "types.h" // u8
#include "disk.h" // DISK_RET_SUCCESS
#include "config.h" // CONFIG_FLOPPY_SUPPORT
#include "biosvar.h" // SET_BDA
#include "util.h" // irq_disable
#include "cmos.h" // inb_cmos
#include "pic.h" // unmask_pic1
#include "bregs.h" // struct bregs
#define BX_FLOPPY_ON_CNT 37 /* 2 seconds */
// New diskette parameter table adding 3 parameters from IBM
// Since no provisions are made for multiple drive types, most
// values in this table are ignored. I set parameters for 1.44M
// floppy here
struct floppy_ext_dbt_s diskette_param_table2 VISIBLE16 = {
.dbt = {
.specify1 = 0xAF,
.specify2 = 0x02, // head load time 0000001, DMA used
.shutoff_ticks = 0x25,
.bps_code = 0x02,
.sectors = 18,
.interblock_len = 0x1B,
.data_len = 0xFF,
.gap_len = 0x6C,
.fill_byte = 0xF6,
.settle_time = 0x0F,
.startup_time = 0x08,
},
.max_track = 79, // maximum track
.data_rate = 0, // data transfer rate
.drive_type = 4, // drive type in cmos
};
void
floppy_drive_setup()
{
if (! CONFIG_FLOPPY_SUPPORT)
return;
dprintf(3, "init floppy drives\n");
u8 type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
u8 out = 0;
u8 num_floppies = 0;
if (type & 0xf0) {
out |= 0x07;
num_floppies++;
}
if (type & 0x0f) {
out |= 0x70;
num_floppies++;
}
SET_BDA(floppy_harddisk_info, out);
// Update equipment word bits for floppy
if (num_floppies == 1)
// 1 drive, ready for boot
SETBITS_BDA(equipment_list_flags, 0x01);
else if (num_floppies == 2)
// 2 drives, ready for boot
SETBITS_BDA(equipment_list_flags, 0x41);
outb(0x02, PORT_DMA1_MASK_REG);
// Enable IRQ6 (handle_0e)
unmask_pic1(PIC1_IRQ6);
}
static inline void
set_diskette_current_cyl(u8 drive, u8 cyl)
{
if (drive)
SET_BDA(floppy_track1, cyl);
else
SET_BDA(floppy_track0, cyl);
}
static u16
get_drive_type(u8 drive)
{
// check CMOS to see if drive exists
u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
if (drive == 0)
drive_type >>= 4;
else
drive_type &= 0x0f;
return drive_type;
}
static u16
floppy_media_known(u8 drive)
{
if (!(GET_BDA(floppy_recalibration_status) & (1<<drive)))
return 0;
u8 v = GET_BDA(floppy_media_state[drive]);
if (!(v & FMS_MEDIA_DRIVE_ESTABLISHED))
return 0;
return 1;
}
static void
floppy_reset_controller()
{
// Reset controller
u8 val8 = inb(PORT_FD_DOR);
outb(val8 & ~0x04, PORT_FD_DOR);
outb(val8 | 0x04, PORT_FD_DOR);
// Wait for controller to come out of reset
while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
;
}
static void
floppy_prepare_controller(u8 drive)
{
CLEARBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
// turn on motor of selected drive, DMA & int enabled, normal operation
u8 prev_reset = inb(PORT_FD_DOR) & 0x04;
u8 dor = 0x10;
if (drive)
dor = 0x20;
dor |= 0x0c;
dor |= drive;
outb(dor, PORT_FD_DOR);
// reset the disk motor timeout value of INT 08
SET_BDA(floppy_motor_counter, BX_FLOPPY_ON_CNT);
// wait for drive readiness
while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
;
if (prev_reset == 0) {
irq_enable();
u8 v;
for (;;) {
v = GET_BDA(floppy_recalibration_status);
if (v & FRS_TIMEOUT)
break;
cpu_relax();
}
irq_disable();
v &= ~FRS_TIMEOUT;
SET_BDA(floppy_recalibration_status, v);
}
}
static int
floppy_pio(u8 *cmd, u8 cmdlen)
{
floppy_prepare_controller(cmd[1] & 1);
// send command to controller
u8 i;
for (i=0; i<cmdlen; i++)
outb(cmd[i], PORT_FD_DATA);
irq_enable();
u8 v;
for (;;) {
if (!GET_BDA(floppy_motor_counter)) {
irq_disable();
floppy_reset_controller();
return -1;
}
v = GET_BDA(floppy_recalibration_status);
if (v & FRS_TIMEOUT)
break;
cpu_relax();
}
irq_disable();
v &= ~FRS_TIMEOUT;
SET_BDA(floppy_recalibration_status, v);
return 0;
}
#define floppy_ret(regs, code) \
__floppy_ret(__func__, __LINE__, (regs), (code))
void
__floppy_ret(const char *fname, int lineno, struct bregs *regs, u8 code)
{
SET_BDA(floppy_last_status, code);
if (code)
__set_code_fail(fname, lineno, regs, code);
else
set_code_success(regs);
}
static int
floppy_cmd(struct bregs *regs, u16 count, u8 *cmd, u8 cmdlen)
{
// es:bx = pointer to where to place information from diskette
// port 04: DMA-1 base and current address, channel 2
// port 05: DMA-1 base and current count, channel 2
u16 page = regs->es >> 12; // upper 4 bits
u16 base_es = regs->es << 4; // lower 16bits contributed by ES
u16 base_address = base_es + regs->bx; // lower 16 bits of address
// contributed by ES:BX
if (base_address < base_es)
// in case of carry, adjust page by 1
page++;
// check for 64K boundary overrun
u16 last_addr = base_address + count;
if (last_addr < base_address) {
floppy_ret(regs, DISK_RET_EBOUNDARY);
return -1;
}
u8 mode_register = 0x4a; // single mode, increment, autoinit disable,
if (cmd[0] == 0xe6)
// read
mode_register = 0x46;
//DEBUGF("floppy dma c2\n");
outb(0x06, PORT_DMA1_MASK_REG);
outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
outb(base_address, PORT_DMA_ADDR_2);
outb(base_address>>8, PORT_DMA_ADDR_2);
outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
outb(count, PORT_DMA_CNT_2);
outb(count>>8, PORT_DMA_CNT_2);
// port 0b: DMA-1 Mode Register
// transfer type=write, channel 2
outb(mode_register, PORT_DMA1_MODE_REG);
// port 81: DMA-1 Page Register, channel 2
outb(page, PORT_DMA_PAGE_2);
outb(0x02, PORT_DMA1_MASK_REG); // unmask channel 2
int ret = floppy_pio(cmd, cmdlen);
if (ret) {
floppy_ret(regs, DISK_RET_ETIMEOUT);
return -1;
}
// check port 3f4 for accessibility to status bytes
if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
BX_PANIC("int13_diskette: ctrl not ready\n");
// read 7 return status bytes from controller
u8 i;
for (i=0; i<7; i++) {
u8 v = inb(PORT_FD_DATA);
cmd[i] = v;
SET_BDA(floppy_return_status[i], v);
}
return 0;
}
static void
floppy_drive_recal(u8 drive)
{
// send Recalibrate command (2 bytes) to controller
u8 data[12];
data[0] = 0x07; // 07: Recalibrate
data[1] = drive; // 0=drive0, 1=drive1
floppy_pio(data, 2);
SETBITS_BDA(floppy_recalibration_status, 1<<drive);
set_diskette_current_cyl(drive, 0);
}
static u16
floppy_media_sense(u8 drive)
{
u16 rv;
u8 config_data, media_state;
floppy_drive_recal(drive);
// for now cheat and get drive type from CMOS,
// assume media is same as drive type
// ** config_data **
// Bitfields for diskette media control:
// Bit(s) Description (Table M0028)
// 7-6 last data rate set by controller
// 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
// 5-4 last diskette drive step rate selected
// 00=0Ch, 01=0Dh, 10=0Eh, 11=0Ah
// 3-2 {data rate at start of operation}
// 1-0 reserved
// ** media_state **
// Bitfields for diskette drive media state:
// Bit(s) Description (Table M0030)
// 7-6 data rate
// 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
// 5 double stepping required (e.g. 360kB in 1.2MB)
// 4 media type established
// 3 drive capable of supporting 4MB media
// 2-0 on exit from BIOS, contains
// 000 trying 360kB in 360kB
// 001 trying 360kB in 1.2MB
// 010 trying 1.2MB in 1.2MB
// 011 360kB in 360kB established
// 100 360kB in 1.2MB established
// 101 1.2MB in 1.2MB established
// 110 reserved
// 111 all other formats/drives
switch (get_drive_type(drive)) {
case 1:
// 360K 5.25" drive
config_data = 0x00; // 0000 0000
media_state = 0x25; // 0010 0101
rv = 1;
break;
case 2:
// 1.2 MB 5.25" drive
config_data = 0x00; // 0000 0000
media_state = 0x25; // 0010 0101 // need double stepping??? (bit 5)
rv = 1;
break;
case 3:
// 720K 3.5" drive
config_data = 0x00; // 0000 0000 ???
media_state = 0x17; // 0001 0111
rv = 1;
break;
case 4:
// 1.44 MB 3.5" drive
config_data = 0x00; // 0000 0000
media_state = 0x17; // 0001 0111
rv = 1;
break;
case 5:
// 2.88 MB 3.5" drive
config_data = 0xCC; // 1100 1100
media_state = 0xD7; // 1101 0111
rv = 1;
break;
//
// Extended floppy size uses special cmos setting
case 6:
// 160k 5.25" drive
config_data = 0x00; // 0000 0000
media_state = 0x27; // 0010 0111
rv = 1;
break;
case 7:
// 180k 5.25" drive
config_data = 0x00; // 0000 0000
media_state = 0x27; // 0010 0111
rv = 1;
break;
case 8:
// 320k 5.25" drive
config_data = 0x00; // 0000 0000
media_state = 0x27; // 0010 0111
rv = 1;
break;
default:
// not recognized
config_data = 0x00; // 0000 0000
media_state = 0x00; // 0000 0000
rv = 0;
}
SET_BDA(floppy_last_data_rate, config_data);
SET_BDA(floppy_media_state[drive], media_state);
return rv;
}
static int
check_drive(struct bregs *regs, u8 drive)
{
// see if drive exists
if (drive > 1 || !get_drive_type(drive)) {
// XXX - return type doesn't match
floppy_ret(regs, DISK_RET_ETIMEOUT);
return -1;
}
// see if media in drive, and type is known
if (floppy_media_known(drive) == 0 && floppy_media_sense(drive) == 0) {
floppy_ret(regs, DISK_RET_EMEDIA);
return -1;
}
return 0;
}
// diskette controller reset
static void
floppy_1300(struct bregs *regs, u8 drive)
{
if (drive > 1) {
floppy_ret(regs, DISK_RET_EPARAM);
return;
}
if (!get_drive_type(drive)) {
floppy_ret(regs, DISK_RET_ETIMEOUT);
return;
}
set_diskette_current_cyl(drive, 0); // current cylinder
floppy_ret(regs, DISK_RET_SUCCESS);
}
// Read Diskette Status
static void
floppy_1301(struct bregs *regs, u8 drive)
{
u8 v = GET_BDA(floppy_last_status);
regs->ah = v;
set_cf(regs, v);
}
// Read Diskette Sectors
static void
floppy_1302(struct bregs *regs, u8 drive)
{
if (check_drive(regs, drive))
goto fail;
u8 num_sectors = regs->al;
u8 track = regs->ch;
u8 sector = regs->cl;
u8 head = regs->dh;
if (head > 1 || sector == 0 || num_sectors == 0
|| track > 79 || num_sectors > 72) {
floppy_ret(regs, DISK_RET_EPARAM);
goto fail;
}
// send read-normal-data command (9 bytes) to controller
u8 data[12];
data[0] = 0xe6; // e6: read normal data
data[1] = (head << 2) | drive; // HD DR1 DR2
data[2] = track;
data[3] = head;
data[4] = sector;
data[5] = 2; // 512 byte sector size
data[6] = sector + num_sectors - 1; // last sector to read on track
data[7] = 0; // Gap length
data[8] = 0xff; // Gap length
int ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
if (ret)
goto fail;
if (data[0] & 0xc0) {
floppy_ret(regs, DISK_RET_ECONTROLLER);
goto fail;
}
// ??? should track be new val from return_status[3] ?
set_diskette_current_cyl(drive, track);
// AL = number of sectors read (same value as passed)
floppy_ret(regs, DISK_RET_SUCCESS);
return;
fail:
regs->al = 0; // no sectors read
}
// Write Diskette Sectors
static void
floppy_1303(struct bregs *regs, u8 drive)
{
if (check_drive(regs, drive))
goto fail;
u8 num_sectors = regs->al;
u8 track = regs->ch;
u8 sector = regs->cl;
u8 head = regs->dh;
if (head > 1 || sector == 0 || num_sectors == 0
|| track > 79 || num_sectors > 72) {
floppy_ret(regs, DISK_RET_EPARAM);
goto fail;
}
// send write-normal-data command (9 bytes) to controller
u8 data[12];
data[0] = 0xc5; // c5: write normal data
data[1] = (head << 2) | drive; // HD DR1 DR2
data[2] = track;
data[3] = head;
data[4] = sector;
data[5] = 2; // 512 byte sector size
data[6] = sector + num_sectors - 1; // last sector to write on track
data[7] = 0; // Gap length
data[8] = 0xff; // Gap length
int ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
if (ret)
goto fail;
if (data[0] & 0xc0) {
if (data[1] & 0x02) {
floppy_ret(regs, DISK_RET_EWRITEPROTECT);
goto fail;
}
BX_PANIC("int13_diskette_function: read error\n");
}
// ??? should track be new val from return_status[3] ?
set_diskette_current_cyl(drive, track);
// AL = number of sectors read (same value as passed)
floppy_ret(regs, DISK_RET_SUCCESS);
return;
fail:
regs->al = 0; // no sectors read
}
// Verify Diskette Sectors
static void
floppy_1304(struct bregs *regs, u8 drive)
{
if (check_drive(regs, drive))
goto fail;
u8 num_sectors = regs->al;
u8 track = regs->ch;
u8 sector = regs->cl;
u8 head = regs->dh;
if (head > 1 || sector == 0 || num_sectors == 0
|| track > 79 || num_sectors > 72) {
floppy_ret(regs, DISK_RET_EPARAM);
goto fail;
}
// ??? should track be new val from return_status[3] ?
set_diskette_current_cyl(drive, track);
// AL = number of sectors verified (same value as passed)
floppy_ret(regs, DISK_RET_SUCCESS);
return;
fail:
regs->al = 0; // no sectors read
}
// format diskette track
static void
floppy_1305(struct bregs *regs, u8 drive)
{
dprintf(3, "floppy f05\n");
if (check_drive(regs, drive))
return;
u8 num_sectors = regs->al;
u8 head = regs->dh;
if (head > 1 || num_sectors == 0 || num_sectors > 18) {
floppy_ret(regs, DISK_RET_EPARAM);
return;
}
// send format-track command (6 bytes) to controller
u8 data[12];
data[0] = 0x4d; // 4d: format track
data[1] = (head << 2) | drive; // HD DR1 DR2
data[2] = 2; // 512 byte sector size
data[3] = num_sectors; // number of sectors per track
data[4] = 0; // Gap length
data[5] = 0xf6; // Fill byte
int ret = floppy_cmd(regs, (num_sectors * 4) - 1, data, 6);
if (ret)
return;
if (data[0] & 0xc0) {
if (data[1] & 0x02) {
floppy_ret(regs, DISK_RET_EWRITEPROTECT);
return;
}
BX_PANIC("int13_diskette_function: read error\n");
}
set_diskette_current_cyl(drive, 0);
floppy_ret(regs, 0);
}
// read diskette drive parameters
static void
floppy_1308(struct bregs *regs, u8 drive)
{
dprintf(3, "floppy f08\n");
u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
u8 num_floppies = 0;
if (drive_type & 0xf0)
num_floppies++;
if (drive_type & 0x0f)
num_floppies++;
if (drive > 1) {
regs->ax = 0;
regs->bx = 0;
regs->cx = 0;
regs->dx = 0;
regs->es = 0;
regs->di = 0;
regs->dl = num_floppies;
set_success(regs);
return;
}
if (drive == 0)
drive_type >>= 4;
else
drive_type &= 0x0f;
regs->bh = 0;
regs->bl = drive_type;
regs->ah = 0;
regs->al = 0;
regs->dl = num_floppies;
switch (drive_type) {
case 0: // none
regs->cx = 0;
regs->dh = 0; // max head #
break;
case 1: // 360KB, 5.25"
regs->cx = 0x2709; // 40 tracks, 9 sectors
regs->dh = 1; // max head #
break;
case 2: // 1.2MB, 5.25"
regs->cx = 0x4f0f; // 80 tracks, 15 sectors
regs->dh = 1; // max head #
break;
case 3: // 720KB, 3.5"
regs->cx = 0x4f09; // 80 tracks, 9 sectors
regs->dh = 1; // max head #
break;
case 4: // 1.44MB, 3.5"
regs->cx = 0x4f12; // 80 tracks, 18 sectors
regs->dh = 1; // max head #
break;
case 5: // 2.88MB, 3.5"
regs->cx = 0x4f24; // 80 tracks, 36 sectors
regs->dh = 1; // max head #
break;
case 6: // 160k, 5.25"
regs->cx = 0x2708; // 40 tracks, 8 sectors
regs->dh = 0; // max head #
break;
case 7: // 180k, 5.25"
regs->cx = 0x2709; // 40 tracks, 9 sectors
regs->dh = 0; // max head #
break;
case 8: // 320k, 5.25"
regs->cx = 0x2708; // 40 tracks, 8 sectors
regs->dh = 1; // max head #
break;
default: // ?
BX_PANIC("floppy: int13: bad floppy type\n");
}
/* set es & di to point to 11 byte diskette param table in ROM */
regs->es = SEG_BIOS;
regs->di = (u32)&diskette_param_table2;
/* disk status not changed upon success */
}
// read diskette drive type
static void
floppy_1315(struct bregs *regs, u8 drive)
{
dprintf(6, "floppy f15\n");
if (drive > 1) {
set_fail(regs);
regs->ah = 0; // only 2 drives supported
// set_diskette_ret_status here ???
return;
}
u8 drive_type = get_drive_type(drive);
regs->ah = (drive_type != 0);
set_success(regs);
}
// get diskette change line status
static void
floppy_1316(struct bregs *regs, u8 drive)
{
if (drive > 1) {
floppy_ret(regs, DISK_RET_EPARAM);
return;
}
floppy_ret(regs, DISK_RET_ECHANGED);
}
static void
floppy_13XX(struct bregs *regs, u8 drive)
{
floppy_ret(regs, DISK_RET_EPARAM);
}
void
floppy_13(struct bregs *regs, u8 drive)
{
if (! CONFIG_FLOPPY_SUPPORT) {
// Minimal stubs
switch (regs->ah) {
case 0x01: floppy_1301(regs, drive); break;
default: floppy_13XX(regs, drive); break;
}
return;
}
switch (regs->ah) {
case 0x00: floppy_1300(regs, drive); break;
case 0x01: floppy_1301(regs, drive); break;
case 0x02: floppy_1302(regs, drive); break;
case 0x03: floppy_1303(regs, drive); break;
case 0x04: floppy_1304(regs, drive); break;
case 0x05: floppy_1305(regs, drive); break;
case 0x08: floppy_1308(regs, drive); break;
case 0x15: floppy_1315(regs, drive); break;
case 0x16: floppy_1316(regs, drive); break;
default: floppy_13XX(regs, drive); break;
}
}
// INT 0Eh Diskette Hardware ISR Entry Point
void VISIBLE16
handle_0e()
{
debug_isr(DEBUG_ISR_0e);
if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0) {
outb(0x08, PORT_FD_DATA); // sense interrupt status
while ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
;
do {
inb(PORT_FD_DATA);
} while ((inb(PORT_FD_STATUS) & 0xc0) == 0xc0);
}
eoi_pic1();
// diskette interrupt has occurred
SETBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
}
// Called from int08 handler.
void
floppy_tick()
{
// time to turn off drive(s)?
u8 fcount = GET_BDA(floppy_motor_counter);
if (fcount) {
fcount--;
SET_BDA(floppy_motor_counter, fcount);
if (fcount == 0)
// turn motor(s) off
outb(inb(PORT_FD_DOR) & 0xcf, PORT_FD_DOR);
}
}