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kernel/drivers/block/amiflop.c

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init repo.
2024-07-22 17:22:30 +08:00
// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/amiga/amiflop.c
*
* Copyright (C) 1993 Greg Harp
* Portions of this driver are based on code contributed by Brad Pepers
*
* revised 28.5.95 by Joerg Dorchain
* - now no bugs(?) any more for both HD & DD
* - added support for 40 Track 5.25" drives, 80-track hopefully behaves
* like 3.5" dd (no way to test - are there any 5.25" drives out there
* that work on an A4000?)
* - wrote formatting routine (maybe dirty, but works)
*
* june/july 1995 added ms-dos support by Joerg Dorchain
* (portions based on messydos.device and various contributors)
* - currently only 9 and 18 sector disks
*
* - fixed a bug with the internal trackbuffer when using multiple
* disks the same time
* - made formatting a bit safer
* - added command line and machine based default for "silent" df0
*
* december 1995 adapted for 1.2.13pl4 by Joerg Dorchain
* - works but I think it's inefficient. (look in redo_fd_request)
* But the changes were very efficient. (only three and a half lines)
*
* january 1996 added special ioctl for tracking down read/write problems
* - usage ioctl(d, RAW_TRACK, ptr); the raw track buffer (MFM-encoded data
* is copied to area. (area should be large enough since no checking is
* done - 30K is currently sufficient). return the actual size of the
* trackbuffer
* - replaced udelays() by a timer (CIAA timer B) for the waits
* needed for the disk mechanic.
*
* february 1996 fixed error recovery and multiple disk access
* - both got broken the first time I tampered with the driver :-(
* - still not safe, but better than before
*
* revised Marts 3rd, 1996 by Jes Sorensen for use in the 1.3.28 kernel.
* - Minor changes to accept the kdev_t.
* - Replaced some more udelays with ms_delays. Udelay is just a loop,
* and so the delay will be different depending on the given
* processor :-(
* - The driver could use a major cleanup because of the new
* major/minor handling that came with kdev_t. It seems to work for
* the time being, but I can't guarantee that it will stay like
* that when we start using 16 (24?) bit minors.
*
* restructured jan 1997 by Joerg Dorchain
* - Fixed Bug accessing multiple disks
* - some code cleanup
* - added trackbuffer for each drive to speed things up
* - fixed some race conditions (who finds the next may send it to me ;-)
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/fd.h>
#include <linux/hdreg.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/major.h>
#include <linux/mutex.h>
#include <linux/fs.h>
#include <linux/blk-mq.h>
#include <linux/elevator.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <asm/setup.h>
#include <linux/uaccess.h>
#include <asm/amigahw.h>
#include <asm/amigaints.h>
#include <asm/irq.h>
#undef DEBUG /* print _LOTS_ of infos */
#define RAW_IOCTL
#ifdef RAW_IOCTL
#define IOCTL_RAW_TRACK 0x5254524B /* 'RTRK' */
#endif
/*
* Defines
*/
/*
* CIAAPRA bits (read only)
*/
#define DSKRDY (0x1<<5) /* disk ready when low */
#define DSKTRACK0 (0x1<<4) /* head at track zero when low */
#define DSKPROT (0x1<<3) /* disk protected when low */
#define DSKCHANGE (0x1<<2) /* low when disk removed */
/*
* CIAAPRB bits (read/write)
*/
#define DSKMOTOR (0x1<<7) /* motor on when low */
#define DSKSEL3 (0x1<<6) /* select drive 3 when low */
#define DSKSEL2 (0x1<<5) /* select drive 2 when low */
#define DSKSEL1 (0x1<<4) /* select drive 1 when low */
#define DSKSEL0 (0x1<<3) /* select drive 0 when low */
#define DSKSIDE (0x1<<2) /* side selection: 0 = upper, 1 = lower */
#define DSKDIREC (0x1<<1) /* step direction: 0=in, 1=out (to trk 0) */
#define DSKSTEP (0x1) /* pulse low to step head 1 track */
/*
* DSKBYTR bits (read only)
*/
#define DSKBYT (1<<15) /* register contains valid byte when set */
#define DMAON (1<<14) /* disk DMA enabled */
#define DISKWRITE (1<<13) /* disk write bit in DSKLEN enabled */
#define WORDEQUAL (1<<12) /* DSKSYNC register match when true */
/* bits 7-0 are data */
/*
* ADKCON/ADKCONR bits
*/
#ifndef SETCLR
#define ADK_SETCLR (1<<15) /* control bit */
#endif
#define ADK_PRECOMP1 (1<<14) /* precompensation selection */
#define ADK_PRECOMP0 (1<<13) /* 00=none, 01=140ns, 10=280ns, 11=500ns */
#define ADK_MFMPREC (1<<12) /* 0=GCR precomp., 1=MFM precomp. */
#define ADK_WORDSYNC (1<<10) /* enable DSKSYNC auto DMA */
#define ADK_MSBSYNC (1<<9) /* when 1, enable sync on MSbit (for GCR) */
#define ADK_FAST (1<<8) /* bit cell: 0=2us (GCR), 1=1us (MFM) */
/*
* DSKLEN bits
*/
#define DSKLEN_DMAEN (1<<15)
#define DSKLEN_WRITE (1<<14)
/*
* INTENA/INTREQ bits
*/
#define DSKINDEX (0x1<<4) /* DSKINDEX bit */
/*
* Misc
*/
#define MFM_SYNC 0x4489 /* standard MFM sync value */
/* Values for FD_COMMAND */
#define FD_RECALIBRATE 0x07 /* move to track 0 */
#define FD_SEEK 0x0F /* seek track */
#define FD_READ 0xE6 /* read with MT, MFM, SKip deleted */
#define FD_WRITE 0xC5 /* write with MT, MFM */
#define FD_SENSEI 0x08 /* Sense Interrupt Status */
#define FD_SPECIFY 0x03 /* specify HUT etc */
#define FD_FORMAT 0x4D /* format one track */
#define FD_VERSION 0x10 /* get version code */
#define FD_CONFIGURE 0x13 /* configure FIFO operation */
#define FD_PERPENDICULAR 0x12 /* perpendicular r/w mode */
#define FD_MAX_UNITS 4 /* Max. Number of drives */
#define FLOPPY_MAX_SECTORS 22 /* Max. Number of sectors per track */
struct fd_data_type {
char *name; /* description of data type */
int sects; /* sectors per track */
int (*read_fkt)(int); /* read whole track */
void (*write_fkt)(int); /* write whole track */
};
struct fd_drive_type {
unsigned long code; /* code returned from drive */
char *name; /* description of drive */
unsigned int tracks; /* number of tracks */
unsigned int heads; /* number of heads */
unsigned int read_size; /* raw read size for one track */
unsigned int write_size; /* raw write size for one track */
unsigned int sect_mult; /* sectors and gap multiplier (HD = 2) */
unsigned int precomp1; /* start track for precomp 1 */
unsigned int precomp2; /* start track for precomp 2 */
unsigned int step_delay; /* time (in ms) for delay after step */
unsigned int settle_time; /* time to settle after dir change */
unsigned int side_time; /* time needed to change sides */
};
struct amiga_floppy_struct {
struct fd_drive_type *type; /* type of floppy for this unit */
struct fd_data_type *dtype; /* type of floppy for this unit */
int track; /* current track (-1 == unknown) */
unsigned char *trackbuf; /* current track (kmaloc()'d */
int blocks; /* total # blocks on disk */
int changed; /* true when not known */
int disk; /* disk in drive (-1 == unknown) */
int motor; /* true when motor is at speed */
int busy; /* true when drive is active */
int dirty; /* true when trackbuf is not on disk */
int status; /* current error code for unit */
struct gendisk *gendisk[2];
struct blk_mq_tag_set tag_set;
};
/*
* Error codes
*/
#define FD_OK 0 /* operation succeeded */
#define FD_ERROR -1 /* general error (seek, read, write, etc) */
#define FD_NOUNIT 1 /* unit does not exist */
#define FD_UNITBUSY 2 /* unit already active */
#define FD_NOTACTIVE 3 /* unit is not active */
#define FD_NOTREADY 4 /* unit is not ready (motor not on/no disk) */
#define MFM_NOSYNC 1
#define MFM_HEADER 2
#define MFM_DATA 3
#define MFM_TRACK 4
/*
* Floppy ID values
*/
#define FD_NODRIVE 0x00000000 /* response when no unit is present */
#define FD_DD_3 0xffffffff /* double-density 3.5" (880K) drive */
#define FD_HD_3 0x55555555 /* high-density 3.5" (1760K) drive */
#define FD_DD_5 0xaaaaaaaa /* double-density 5.25" (440K) drive */
static DEFINE_MUTEX(amiflop_mutex);
static unsigned long int fd_def_df0 = FD_DD_3; /* default for df0 if it doesn't identify */
module_param(fd_def_df0, ulong, 0);
MODULE_LICENSE("GPL");
/*
* Macros
*/
#define MOTOR_ON (ciab.prb &= ~DSKMOTOR)
#define MOTOR_OFF (ciab.prb |= DSKMOTOR)
#define SELECT(mask) (ciab.prb &= ~mask)
#define DESELECT(mask) (ciab.prb |= mask)
#define SELMASK(drive) (1 << (3 + (drive & 3)))
static struct fd_drive_type drive_types[] = {
/* code name tr he rdsz wrsz sm pc1 pc2 sd st st*/
/* warning: times are now in milliseconds (ms) */
{ FD_DD_3, "DD 3.5", 80, 2, 14716, 13630, 1, 80,161, 3, 18, 1},
{ FD_HD_3, "HD 3.5", 80, 2, 28344, 27258, 2, 80,161, 3, 18, 1},
{ FD_DD_5, "DD 5.25", 40, 2, 14716, 13630, 1, 40, 81, 6, 30, 2},
{ FD_NODRIVE, "No Drive", 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
};
static int num_dr_types = ARRAY_SIZE(drive_types);
static int amiga_read(int), dos_read(int);
static void amiga_write(int), dos_write(int);
static struct fd_data_type data_types[] = {
{ "Amiga", 11 , amiga_read, amiga_write},
{ "MS-Dos", 9, dos_read, dos_write}
};
/* current info on each unit */
static struct amiga_floppy_struct unit[FD_MAX_UNITS];
static struct timer_list flush_track_timer[FD_MAX_UNITS];
static struct timer_list post_write_timer;
static unsigned long post_write_timer_drive;
static struct timer_list motor_on_timer;
static struct timer_list motor_off_timer[FD_MAX_UNITS];
static int on_attempts;
/* Synchronization of FDC access */
/* request loop (trackbuffer) */
static volatile int fdc_busy = -1;
static volatile int fdc_nested;
static DECLARE_WAIT_QUEUE_HEAD(fdc_wait);
static DECLARE_COMPLETION(motor_on_completion);
static volatile int selected = -1; /* currently selected drive */
static int writepending;
static int writefromint;
static char *raw_buf;
static DEFINE_SPINLOCK(amiflop_lock);
#define RAW_BUF_SIZE 30000 /* size of raw disk data */
/*
* These are global variables, as that's the easiest way to give
* information to interrupts. They are the data used for the current
* request.
*/
static volatile char block_flag;
static DECLARE_WAIT_QUEUE_HEAD(wait_fd_block);
/* MS-Dos MFM Coding tables (should go quick and easy) */
static unsigned char mfmencode[16]={
0x2a, 0x29, 0x24, 0x25, 0x12, 0x11, 0x14, 0x15,
0x4a, 0x49, 0x44, 0x45, 0x52, 0x51, 0x54, 0x55
};
static unsigned char mfmdecode[128];
/* floppy internal millisecond timer stuff */
static DECLARE_COMPLETION(ms_wait_completion);
#define MS_TICKS ((amiga_eclock+50)/1000)
/*
* Note that MAX_ERRORS=X doesn't imply that we retry every bad read
* max X times - some types of errors increase the errorcount by 2 or
* even 3, so we might actually retry only X/2 times before giving up.
*/
#define MAX_ERRORS 12
#define custom amiga_custom
/* Prevent "aliased" accesses. */
static int fd_ref[4] = { 0,0,0,0 };
static int fd_device[4] = { 0, 0, 0, 0 };
/*
* Here come the actual hardware access and helper functions.
* They are not reentrant and single threaded because all drives
* share the same hardware and the same trackbuffer.
*/
/* Milliseconds timer */
static irqreturn_t ms_isr(int irq, void *dummy)
{
complete(&ms_wait_completion);
return IRQ_HANDLED;
}
/* all waits are queued up
A more generic routine would do a schedule a la timer.device */
static void ms_delay(int ms)
{
int ticks;
static DEFINE_MUTEX(mutex);
if (ms > 0) {
mutex_lock(&mutex);
ticks = MS_TICKS*ms-1;
ciaa.tblo=ticks%256;
ciaa.tbhi=ticks/256;
ciaa.crb=0x19; /*count eclock, force load, one-shoot, start */
wait_for_completion(&ms_wait_completion);
mutex_unlock(&mutex);
}
}
/* Hardware semaphore */
/* returns true when we would get the semaphore */
static inline int try_fdc(int drive)
{
drive &= 3;
return ((fdc_busy < 0) || (fdc_busy == drive));
}
static void get_fdc(int drive)
{
unsigned long flags;
drive &= 3;
#ifdef DEBUG
printk("get_fdc: drive %d fdc_busy %d fdc_nested %d\n",drive,fdc_busy,fdc_nested);
#endif
local_irq_save(flags);
wait_event(fdc_wait, try_fdc(drive));
fdc_busy = drive;
fdc_nested++;
local_irq_restore(flags);
}
static inline void rel_fdc(void)
{
#ifdef DEBUG
if (fdc_nested == 0)
printk("fd: unmatched rel_fdc\n");
printk("rel_fdc: fdc_busy %d fdc_nested %d\n",fdc_busy,fdc_nested);
#endif
fdc_nested--;
if (fdc_nested == 0) {
fdc_busy = -1;
wake_up(&fdc_wait);
}
}
static void fd_select (int drive)
{
unsigned char prb = ~0;
drive&=3;
#ifdef DEBUG
printk("selecting %d\n",drive);
#endif
if (drive == selected)
return;
get_fdc(drive);
selected = drive;
if (unit[drive].track % 2 != 0)
prb &= ~DSKSIDE;
if (unit[drive].motor == 1)
prb &= ~DSKMOTOR;
ciab.prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));
ciab.prb = prb;
prb &= ~SELMASK(drive);
ciab.prb = prb;
rel_fdc();
}
static void fd_deselect (int drive)
{
unsigned char prb;
unsigned long flags;
drive&=3;
#ifdef DEBUG
printk("deselecting %d\n",drive);
#endif
if (drive != selected) {
printk(KERN_WARNING "Deselecting drive %d while %d was selected!\n",drive,selected);
return;
}
get_fdc(drive);
local_irq_save(flags);
selected = -1;
prb = ciab.prb;
prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));
ciab.prb = prb;
local_irq_restore (flags);
rel_fdc();
}
static void motor_on_callback(struct timer_list *unused)
{
if (!(ciaa.pra & DSKRDY) || --on_attempts == 0) {
complete_all(&motor_on_completion);
} else {
motor_on_timer.expires = jiffies + HZ/10;
add_timer(&motor_on_timer);
}
}
static int fd_motor_on(int nr)
{
nr &= 3;
del_timer(motor_off_timer + nr);
if (!unit[nr].motor) {
unit[nr].motor = 1;
fd_select(nr);
reinit_completion(&motor_on_completion);
mod_timer(&motor_on_timer, jiffies + HZ/2);
on_attempts = 10;
wait_for_completion(&motor_on_completion);
fd_deselect(nr);
}
if (on_attempts == 0) {
on_attempts = -1;
#if 0
printk (KERN_ERR "motor_on failed, turning motor off\n");
fd_motor_off (motor_off_timer + nr);
return 0;
#else
printk (KERN_WARNING "DSKRDY not set after 1.5 seconds - assuming drive is spinning notwithstanding\n");
#endif
}
return 1;
}
static void fd_motor_off(struct timer_list *timer)
{
unsigned long drive = ((unsigned long)timer -
(unsigned long)&motor_off_timer[0]) /
sizeof(motor_off_timer[0]);
drive&=3;
if (!try_fdc(drive)) {
/* We would be blocked in an interrupt, so try again later */
timer->expires = jiffies + 1;
add_timer(timer);
return;
}
unit[drive].motor = 0;
fd_select(drive);
udelay (1);
fd_deselect(drive);
}
static void floppy_off (unsigned int nr)
{
int drive;
drive = nr & 3;
mod_timer(motor_off_timer + drive, jiffies + 3*HZ);
}
static int fd_calibrate(int drive)
{
unsigned char prb;
int n;
drive &= 3;
get_fdc(drive);
if (!fd_motor_on (drive))
return 0;
fd_select (drive);
prb = ciab.prb;
prb |= DSKSIDE;
prb &= ~DSKDIREC;
ciab.prb = prb;
for (n = unit[drive].type->tracks/2; n != 0; --n) {
if (ciaa.pra & DSKTRACK0)
break;
prb &= ~DSKSTEP;
ciab.prb = prb;
prb |= DSKSTEP;
udelay (2);
ciab.prb = prb;
ms_delay(unit[drive].type->step_delay);
}
ms_delay (unit[drive].type->settle_time);
prb |= DSKDIREC;
n = unit[drive].type->tracks + 20;
for (;;) {
prb &= ~DSKSTEP;
ciab.prb = prb;
prb |= DSKSTEP;
udelay (2);
ciab.prb = prb;
ms_delay(unit[drive].type->step_delay + 1);
if ((ciaa.pra & DSKTRACK0) == 0)
break;
if (--n == 0) {
printk (KERN_ERR "fd%d: calibrate failed, turning motor off\n", drive);
fd_motor_off (motor_off_timer + drive);
unit[drive].track = -1;
rel_fdc();
return 0;
}
}
unit[drive].track = 0;
ms_delay(unit[drive].type->settle_time);
rel_fdc();
fd_deselect(drive);
return 1;
}
static int fd_seek(int drive, int track)
{
unsigned char prb;
int cnt;
#ifdef DEBUG
printk("seeking drive %d to track %d\n",drive,track);
#endif
drive &= 3;
get_fdc(drive);
if (unit[drive].track == track) {
rel_fdc();
return 1;
}
if (!fd_motor_on(drive)) {
rel_fdc();
return 0;
}
if (unit[drive].track < 0 && !fd_calibrate(drive)) {
rel_fdc();
return 0;
}
fd_select (drive);
cnt = unit[drive].track/2 - track/2;
prb = ciab.prb;
prb |= DSKSIDE | DSKDIREC;
if (track % 2 != 0)
prb &= ~DSKSIDE;
if (cnt < 0) {
cnt = - cnt;
prb &= ~DSKDIREC;
}
ciab.prb = prb;
if (track % 2 != unit[drive].track % 2)
ms_delay (unit[drive].type->side_time);
unit[drive].track = track;
if (cnt == 0) {
rel_fdc();
fd_deselect(drive);
return 1;
}
do {
prb &= ~DSKSTEP;
ciab.prb = prb;
prb |= DSKSTEP;
udelay (1);
ciab.prb = prb;
ms_delay (unit[drive].type->step_delay);
} while (--cnt != 0);
ms_delay (unit[drive].type->settle_time);
rel_fdc();
fd_deselect(drive);
return 1;
}
static unsigned long fd_get_drive_id(int drive)
{
int i;
ulong id = 0;
drive&=3;
get_fdc(drive);
/* set up for ID */
MOTOR_ON;
udelay(2);
SELECT(SELMASK(drive));
udelay(2);
DESELECT(SELMASK(drive));
udelay(2);
MOTOR_OFF;
udelay(2);
SELECT(SELMASK(drive));
udelay(2);
DESELECT(SELMASK(drive));
udelay(2);
/* loop and read disk ID */
for (i=0; i<32; i++) {
SELECT(SELMASK(drive));
udelay(2);
/* read and store value of DSKRDY */
id <<= 1;
id |= (ciaa.pra & DSKRDY) ? 0 : 1; /* cia regs are low-active! */
DESELECT(SELMASK(drive));
}
rel_fdc();
/*
* RB: At least A500/A2000's df0: don't identify themselves.
* As every (real) Amiga has at least a 3.5" DD drive as df0:
* we default to that if df0: doesn't identify as a certain
* type.
*/
if(drive == 0 && id == FD_NODRIVE)
{
id = fd_def_df0;
printk(KERN_NOTICE "fd: drive 0 didn't identify, setting default %08lx\n", (ulong)fd_def_df0);
}
/* return the ID value */
return (id);
}
static irqreturn_t fd_block_done(int irq, void *dummy)
{
if (block_flag)
custom.dsklen = 0x4000;
if (block_flag == 2) { /* writing */
writepending = 2;
post_write_timer.expires = jiffies + 1; /* at least 2 ms */
post_write_timer_drive = selected;
add_timer(&post_write_timer);
}
else { /* reading */
block_flag = 0;
wake_up (&wait_fd_block);
}
return IRQ_HANDLED;
}
static void raw_read(int drive)
{
drive&=3;
get_fdc(drive);
wait_event(wait_fd_block, !block_flag);
fd_select(drive);
/* setup adkcon bits correctly */
custom.adkcon = ADK_MSBSYNC;
custom.adkcon = ADK_SETCLR|ADK_WORDSYNC|ADK_FAST;
custom.dsksync = MFM_SYNC;
custom.dsklen = 0;
custom.dskptr = (u_char *)ZTWO_PADDR((u_char *)raw_buf);
custom.dsklen = unit[drive].type->read_size/sizeof(short) | DSKLEN_DMAEN;
custom.dsklen = unit[drive].type->read_size/sizeof(short) | DSKLEN_DMAEN;
block_flag = 1;
wait_event(wait_fd_block, !block_flag);
custom.dsklen = 0;
fd_deselect(drive);
rel_fdc();
}
static int raw_write(int drive)
{
ushort adk;
drive&=3;
get_fdc(drive); /* corresponds to rel_fdc() in post_write() */
if ((ciaa.pra & DSKPROT) == 0) {
rel_fdc();
return 0;
}
wait_event(wait_fd_block, !block_flag);
fd_select(drive);
/* clear adkcon bits */
custom.adkcon = ADK_PRECOMP1|ADK_PRECOMP0|ADK_WORDSYNC|ADK_MSBSYNC;
/* set appropriate adkcon bits */
adk = ADK_SETCLR|ADK_FAST;
if ((ulong)unit[drive].track >= unit[drive].type->precomp2)
adk |= ADK_PRECOMP1;
else if ((ulong)unit[drive].track >= unit[drive].type->precomp1)
adk |= ADK_PRECOMP0;
custom.adkcon = adk;
custom.dsklen = DSKLEN_WRITE;
custom.dskptr = (u_char *)ZTWO_PADDR((u_char *)raw_buf);
custom.dsklen = unit[drive].type->write_size/sizeof(short) | DSKLEN_DMAEN|DSKLEN_WRITE;
custom.dsklen = unit[drive].type->write_size/sizeof(short) | DSKLEN_DMAEN|DSKLEN_WRITE;
block_flag = 2;
return 1;
}
/*
* to be called at least 2ms after the write has finished but before any
* other access to the hardware.
*/
static void post_write (unsigned long drive)
{
#ifdef DEBUG
printk("post_write for drive %ld\n",drive);
#endif
drive &= 3;
custom.dsklen = 0;
block_flag = 0;
writepending = 0;
writefromint = 0;
unit[drive].dirty = 0;
wake_up(&wait_fd_block);
fd_deselect(drive);
rel_fdc(); /* corresponds to get_fdc() in raw_write */
}
static void post_write_callback(struct timer_list *timer)
{
post_write(post_write_timer_drive);
}
/*
* The following functions are to convert the block contents into raw data
* written to disk and vice versa.
* (Add other formats here ;-))
*/
static unsigned long scan_sync(unsigned long raw, unsigned long end)
{
ushort *ptr = (ushort *)raw, *endp = (ushort *)end;
while (ptr < endp && *ptr++ != 0x4489)
;
if (ptr < endp) {
while (*ptr == 0x4489 && ptr < endp)
ptr++;
return (ulong)ptr;
}
return 0;
}
static inline unsigned long checksum(unsigned long *addr, int len)
{
unsigned long csum = 0;
len /= sizeof(*addr);
while (len-- > 0)
csum ^= *addr++;
csum = ((csum>>1) & 0x55555555) ^ (csum & 0x55555555);
return csum;
}
static unsigned long decode (unsigned long *data, unsigned long *raw,
int len)
{
ulong *odd, *even;
/* convert length from bytes to longwords */
len >>= 2;
odd = raw;
even = odd + len;
/* prepare return pointer */
raw += len * 2;
do {
*data++ = ((*odd++ & 0x55555555) << 1) | (*even++ & 0x55555555);
} while (--len != 0);
return (ulong)raw;
}
struct header {
unsigned char magic;
unsigned char track;
unsigned char sect;
unsigned char ord;
unsigned char labels[16];
unsigned long hdrchk;
unsigned long datachk;
};
static int amiga_read(int drive)
{
unsigned long raw;
unsigned long end;
int scnt;
unsigned long csum;
struct header hdr;
drive&=3;
raw = (long) raw_buf;
end = raw + unit[drive].type->read_size;
for (scnt = 0;scnt < unit[drive].dtype->sects * unit[drive].type->sect_mult; scnt++) {
if (!(raw = scan_sync(raw, end))) {
printk (KERN_INFO "can't find sync for sector %d\n", scnt);
return MFM_NOSYNC;
}
raw = decode ((ulong *)&hdr.magic, (ulong *)raw, 4);
raw = decode ((ulong *)&hdr.labels, (ulong *)raw, 16);
raw = decode ((ulong *)&hdr.hdrchk, (ulong *)raw, 4);
raw = decode ((ulong *)&hdr.datachk, (ulong *)raw, 4);
csum = checksum((ulong *)&hdr,
(char *)&hdr.hdrchk-(char *)&hdr);
#ifdef DEBUG
printk ("(%x,%d,%d,%d) (%lx,%lx,%lx,%lx) %lx %lx\n",
hdr.magic, hdr.track, hdr.sect, hdr.ord,
*(ulong *)&hdr.labels[0], *(ulong *)&hdr.labels[4],
*(ulong *)&hdr.labels[8], *(ulong *)&hdr.labels[12],
hdr.hdrchk, hdr.datachk);
#endif
if (hdr.hdrchk != csum) {
printk(KERN_INFO "MFM_HEADER: %08lx,%08lx\n", hdr.hdrchk, csum);
return MFM_HEADER;
}
/* verify track */
if (hdr.track != unit[drive].track) {
printk(KERN_INFO "MFM_TRACK: %d, %d\n", hdr.track, unit[drive].track);
return MFM_TRACK;
}
raw = decode ((ulong *)(unit[drive].trackbuf + hdr.sect*512),
(ulong *)raw, 512);
csum = checksum((ulong *)(unit[drive].trackbuf + hdr.sect*512), 512);
if (hdr.datachk != csum) {
printk(KERN_INFO "MFM_DATA: (%x:%d:%d:%d) sc=%d %lx, %lx\n",
hdr.magic, hdr.track, hdr.sect, hdr.ord, scnt,
hdr.datachk, csum);
printk (KERN_INFO "data=(%lx,%lx,%lx,%lx)\n",
((ulong *)(unit[drive].trackbuf+hdr.sect*512))[0],
((ulong *)(unit[drive].trackbuf+hdr.sect*512))[1],
((ulong *)(unit[drive].trackbuf+hdr.sect*512))[2],
((ulong *)(unit[drive].trackbuf+hdr.sect*512))[3]);
return MFM_DATA;
}
}
return 0;
}
static void encode(unsigned long data, unsigned long *dest)
{
unsigned long data2;
data &= 0x55555555;
data2 = data ^ 0x55555555;
data |= ((data2 >> 1) | 0x80000000) & (data2 << 1);
if (*(dest - 1) & 0x00000001)
data &= 0x7FFFFFFF;
*dest = data;
}
static void encode_block(unsigned long *dest, unsigned long *src, int len)
{
int cnt, to_cnt = 0;
unsigned long data;
/* odd bits */
for (cnt = 0; cnt < len / 4; cnt++) {
data = src[cnt] >> 1;
encode(data, dest + to_cnt++);
}
/* even bits */
for (cnt = 0; cnt < len / 4; cnt++) {
data = src[cnt];
encode(data, dest + to_cnt++);
}
}
static unsigned long *putsec(int disk, unsigned long *raw, int cnt)
{
struct header hdr;
int i;
disk&=3;
*raw = (raw[-1]&1) ? 0x2AAAAAAA : 0xAAAAAAAA;
raw++;
*raw++ = 0x44894489;
hdr.magic = 0xFF;
hdr.track = unit[disk].track;
hdr.sect = cnt;
hdr.ord = unit[disk].dtype->sects * unit[disk].type->sect_mult - cnt;
for (i = 0; i < 16; i++)
hdr.labels[i] = 0;
hdr.hdrchk = checksum((ulong *)&hdr,
(char *)&hdr.hdrchk-(char *)&hdr);
hdr.datachk = checksum((ulong *)(unit[disk].trackbuf+cnt*512), 512);
encode_block(raw, (ulong *)&hdr.magic, 4);
raw += 2;
encode_block(raw, (ulong *)&hdr.labels, 16);
raw += 8;
encode_block(raw, (ulong *)&hdr.hdrchk, 4);
raw += 2;
encode_block(raw, (ulong *)&hdr.datachk, 4);
raw += 2;
encode_block(raw, (ulong *)(unit[disk].trackbuf+cnt*512), 512);
raw += 256;
return raw;
}
static void amiga_write(int disk)
{
unsigned int cnt;
unsigned long *ptr = (unsigned long *)raw_buf;
disk&=3;
/* gap space */
for (cnt = 0; cnt < 415 * unit[disk].type->sect_mult; cnt++)
*ptr++ = 0xaaaaaaaa;
/* sectors */
for (cnt = 0; cnt < unit[disk].dtype->sects * unit[disk].type->sect_mult; cnt++)
ptr = putsec (disk, ptr, cnt);
*(ushort *)ptr = (ptr[-1]&1) ? 0x2AA8 : 0xAAA8;
}
struct dos_header {
unsigned char track, /* 0-80 */
side, /* 0-1 */
sec, /* 0-...*/
len_desc;/* 2 */
unsigned short crc; /* on 68000 we got an alignment problem,
but this compiler solves it by adding silently
adding a pad byte so data won't fit
and this took about 3h to discover.... */
unsigned char gap1[22]; /* for longword-alignedness (0x4e) */
};
/* crc routines are borrowed from the messydos-handler */
/* excerpt from the messydos-device
; The CRC is computed not only over the actual data, but including
; the SYNC mark (3 * $a1) and the 'ID/DATA - Address Mark' ($fe/$fb).
; As we don't read or encode these fields into our buffers, we have to
; preload the registers containing the CRC with the values they would have
; after stepping over these fields.
;
; How CRCs "really" work:
;
; First, you should regard a bitstring as a series of coefficients of
; polynomials. We calculate with these polynomials in modulo-2
; arithmetic, in which both add and subtract are done the same as
; exclusive-or. Now, we modify our data (a very long polynomial) in
; such a way that it becomes divisible by the CCITT-standard 16-bit
; 16 12 5
; polynomial: x + x + x + 1, represented by $11021. The easiest
; way to do this would be to multiply (using proper arithmetic) our
; datablock with $11021. So we have:
; data * $11021 =
; data * ($10000 + $1021) =
; data * $10000 + data * $1021
; The left part of this is simple: Just add two 0 bytes. But then
; the right part (data $1021) remains difficult and even could have
; a carry into the left part. The solution is to use a modified
; multiplication, which has a result that is not correct, but with
; a difference of any multiple of $11021. We then only need to keep
; the 16 least significant bits of the result.
;
; The following algorithm does this for us:
;
; unsigned char *data, c, crclo, crchi;
; while (not done) {
; c = *data++ + crchi;
; crchi = (@ c) >> 8 + crclo;
; crclo = @ c;
; }
;
; Remember, + is done with EOR, the @ operator is in two tables (high
; and low byte separately), which is calculated as
;
; $1021 * (c & $F0)
; xor $1021 * (c & $0F)
; xor $1021 * (c >> 4) (* is regular multiplication)
;
;
; Anyway, the end result is the same as the remainder of the division of
; the data by $11021. I am afraid I need to study theory a bit more...
my only works was to code this from manx to C....
*/
static ushort dos_crc(void * data_a3, int data_d0, int data_d1, int data_d3)
{
static unsigned char CRCTable1[] = {
0x00,0x10,0x20,0x30,0x40,0x50,0x60,0x70,0x81,0x91,0xa1,0xb1,0xc1,0xd1,0xe1,0xf1,
0x12,0x02,0x32,0x22,0x52,0x42,0x72,0x62,0x93,0x83,0xb3,0xa3,0xd3,0xc3,0xf3,0xe3,
0x24,0x34,0x04,0x14,0x64,0x74,0x44,0x54,0xa5,0xb5,0x85,0x95,0xe5,0xf5,0xc5,0xd5,
0x36,0x26,0x16,0x06,0x76,0x66,0x56,0x46,0xb7,0xa7,0x97,0x87,0xf7,0xe7,0xd7,0xc7,
0x48,0x58,0x68,0x78,0x08,0x18,0x28,0x38,0xc9,0xd9,0xe9,0xf9,0x89,0x99,0xa9,0xb9,
0x5a,0x4a,0x7a,0x6a,0x1a,0x0a,0x3a,0x2a,0xdb,0xcb,0xfb,0xeb,0x9b,0x8b,0xbb,0xab,
0x6c,0x7c,0x4c,0x5c,0x2c,0x3c,0x0c,0x1c,0xed,0xfd,0xcd,0xdd,0xad,0xbd,0x8d,0x9d,
0x7e,0x6e,0x5e,0x4e,0x3e,0x2e,0x1e,0x0e,0xff,0xef,0xdf,0xcf,0xbf,0xaf,0x9f,0x8f,
0x91,0x81,0xb1,0xa1,0xd1,0xc1,0xf1,0xe1,0x10,0x00,0x30,0x20,0x50,0x40,0x70,0x60,
0x83,0x93,0xa3,0xb3,0xc3,0xd3,0xe3,0xf3,0x02,0x12,0x22,0x32,0x42,0x52,0x62,0x72,
0xb5,0xa5,0x95,0x85,0xf5,0xe5,0xd5,0xc5,0x34,0x24,0x14,0x04,0x74,0x64,0x54,0x44,
0xa7,0xb7,0x87,0x97,0xe7,0xf7,0xc7,0xd7,0x26,0x36,0x06,0x16,0x66,0x76,0x46,0x56,
0xd9,0xc9,0xf9,0xe9,0x99,0x89,0xb9,0xa9,0x58,0x48,0x78,0x68,0x18,0x08,0x38,0x28,
0xcb,0xdb,0xeb,0xfb,0x8b,0x9b,0xab,0xbb,0x4a,0x5a,0x6a,0x7a,0x0a,0x1a,0x2a,0x3a,
0xfd,0xed,0xdd,0xcd,0xbd,0xad,0x9d,0x8d,0x7c,0x6c,0x5c,0x4c,0x3c,0x2c,0x1c,0x0c,
0xef,0xff,0xcf,0xdf,0xaf,0xbf,0x8f,0x9f,0x6e,0x7e,0x4e,0x5e,0x2e,0x3e,0x0e,0x1e
};
static unsigned char CRCTable2[] = {
0x00,0x21,0x42,0x63,0x84,0xa5,0xc6,0xe7,0x08,0x29,0x4a,0x6b,0x8c,0xad,0xce,0xef,
0x31,0x10,0x73,0x52,0xb5,0x94,0xf7,0xd6,0x39,0x18,0x7b,0x5a,0xbd,0x9c,0xff,0xde,
0x62,0x43,0x20,0x01,0xe6,0xc7,0xa4,0x85,0x6a,0x4b,0x28,0x09,0xee,0xcf,0xac,0x8d,
0x53,0x72,0x11,0x30,0xd7,0xf6,0x95,0xb4,0x5b,0x7a,0x19,0x38,0xdf,0xfe,0x9d,0xbc,
0xc4,0xe5,0x86,0xa7,0x40,0x61,0x02,0x23,0xcc,0xed,0x8e,0xaf,0x48,0x69,0x0a,0x2b,
0xf5,0xd4,0xb7,0x96,0x71,0x50,0x33,0x12,0xfd,0xdc,0xbf,0x9e,0x79,0x58,0x3b,0x1a,
0xa6,0x87,0xe4,0xc5,0x22,0x03,0x60,0x41,0xae,0x8f,0xec,0xcd,0x2a,0x0b,0x68,0x49,
0x97,0xb6,0xd5,0xf4,0x13,0x32,0x51,0x70,0x9f,0xbe,0xdd,0xfc,0x1b,0x3a,0x59,0x78,
0x88,0xa9,0xca,0xeb,0x0c,0x2d,0x4e,0x6f,0x80,0xa1,0xc2,0xe3,0x04,0x25,0x46,0x67,
0xb9,0x98,0xfb,0xda,0x3d,0x1c,0x7f,0x5e,0xb1,0x90,0xf3,0xd2,0x35,0x14,0x77,0x56,
0xea,0xcb,0xa8,0x89,0x6e,0x4f,0x2c,0x0d,0xe2,0xc3,0xa0,0x81,0x66,0x47,0x24,0x05,
0xdb,0xfa,0x99,0xb8,0x5f,0x7e,0x1d,0x3c,0xd3,0xf2,0x91,0xb0,0x57,0x76,0x15,0x34,
0x4c,0x6d,0x0e,0x2f,0xc8,0xe9,0x8a,0xab,0x44,0x65,0x06,0x27,0xc0,0xe1,0x82,0xa3,
0x7d,0x5c,0x3f,0x1e,0xf9,0xd8,0xbb,0x9a,0x75,0x54,0x37,0x16,0xf1,0xd0,0xb3,0x92,
0x2e,0x0f,0x6c,0x4d,0xaa,0x8b,0xe8,0xc9,0x26,0x07,0x64,0x45,0xa2,0x83,0xe0,0xc1,
0x1f,0x3e,0x5d,0x7c,0x9b,0xba,0xd9,0xf8,0x17,0x36,0x55,0x74,0x93,0xb2,0xd1,0xf0
};
/* look at the asm-code - what looks in C a bit strange is almost as good as handmade */
register int i;
register unsigned char *CRCT1, *CRCT2, *data, c, crch, crcl;
CRCT1=CRCTable1;
CRCT2=CRCTable2;
data=data_a3;
crcl=data_d1;
crch=data_d0;
for (i=data_d3; i>=0; i--) {
c = (*data++) ^ crch;
crch = CRCT1[c] ^ crcl;
crcl = CRCT2[c];
}
return (crch<<8)|crcl;
}
static inline ushort dos_hdr_crc (struct dos_header *hdr)
{
return dos_crc(&(hdr->track), 0xb2, 0x30, 3); /* precomputed magic */
}
static inline ushort dos_data_crc(unsigned char *data)
{
return dos_crc(data, 0xe2, 0x95 ,511); /* precomputed magic */
}
static inline unsigned char dos_decode_byte(ushort word)
{
register ushort w2;
register unsigned char byte;
register unsigned char *dec = mfmdecode;
w2=word;
w2>>=8;
w2&=127;
byte = dec[w2];
byte <<= 4;
w2 = word & 127;
byte |= dec[w2];
return byte;
}
static unsigned long dos_decode(unsigned char *data, unsigned short *raw, int len)
{
int i;
for (i = 0; i < len; i++)
*data++=dos_decode_byte(*raw++);
return ((ulong)raw);
}
#ifdef DEBUG
static void dbg(unsigned long ptr)
{
printk("raw data @%08lx: %08lx, %08lx ,%08lx, %08lx\n", ptr,
((ulong *)ptr)[0], ((ulong *)ptr)[1],
((ulong *)ptr)[2], ((ulong *)ptr)[3]);
}
#endif
static int dos_read(int drive)
{
unsigned long end;
unsigned long raw;
int scnt;
unsigned short crc,data_crc[2];
struct dos_header hdr;
drive&=3;
raw = (long) raw_buf;
end = raw + unit[drive].type->read_size;
for (scnt=0; scnt < unit[drive].dtype->sects * unit[drive].type->sect_mult; scnt++) {
do { /* search for the right sync of each sec-hdr */
if (!(raw = scan_sync (raw, end))) {
printk(KERN_INFO "dos_read: no hdr sync on "
"track %d, unit %d for sector %d\n",
unit[drive].track,drive,scnt);
return MFM_NOSYNC;
}
#ifdef DEBUG
dbg(raw);
#endif
} while (*((ushort *)raw)!=0x5554); /* loop usually only once done */
raw+=2; /* skip over headermark */
raw = dos_decode((unsigned char *)&hdr,(ushort *) raw,8);
crc = dos_hdr_crc(&hdr);
#ifdef DEBUG
printk("(%3d,%d,%2d,%d) %x\n", hdr.track, hdr.side,
hdr.sec, hdr.len_desc, hdr.crc);
#endif
if (crc != hdr.crc) {
printk(KERN_INFO "dos_read: MFM_HEADER %04x,%04x\n",
hdr.crc, crc);
return MFM_HEADER;
}
if (hdr.track != unit[drive].track/unit[drive].type->heads) {
printk(KERN_INFO "dos_read: MFM_TRACK %d, %d\n",
hdr.track,
unit[drive].track/unit[drive].type->heads);
return MFM_TRACK;
}
if (hdr.side != unit[drive].track%unit[drive].type->heads) {
printk(KERN_INFO "dos_read: MFM_SIDE %d, %d\n",
hdr.side,
unit[drive].track%unit[drive].type->heads);
return MFM_TRACK;
}
if (hdr.len_desc != 2) {
printk(KERN_INFO "dos_read: unknown sector len "
"descriptor %d\n", hdr.len_desc);
return MFM_DATA;
}
#ifdef DEBUG
printk("hdr accepted\n");
#endif
if (!(raw = scan_sync (raw, end))) {
printk(KERN_INFO "dos_read: no data sync on track "
"%d, unit %d for sector%d, disk sector %d\n",
unit[drive].track, drive, scnt, hdr.sec);
return MFM_NOSYNC;
}
#ifdef DEBUG
dbg(raw);
#endif
if (*((ushort *)raw)!=0x5545) {
printk(KERN_INFO "dos_read: no data mark after "
"sync (%d,%d,%d,%d) sc=%d\n",
hdr.track,hdr.side,hdr.sec,hdr.len_desc,scnt);
return MFM_NOSYNC;
}
raw+=2; /* skip data mark (included in checksum) */
raw = dos_decode((unsigned char *)(unit[drive].trackbuf + (hdr.sec - 1) * 512), (ushort *) raw, 512);
raw = dos_decode((unsigned char *)data_crc,(ushort *) raw,4);
crc = dos_data_crc(unit[drive].trackbuf + (hdr.sec - 1) * 512);
if (crc != data_crc[0]) {
printk(KERN_INFO "dos_read: MFM_DATA (%d,%d,%d,%d) "
"sc=%d, %x %x\n", hdr.track, hdr.side,
hdr.sec, hdr.len_desc, scnt,data_crc[0], crc);
printk(KERN_INFO "data=(%lx,%lx,%lx,%lx,...)\n",
((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[0],
((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[1],
((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[2],
((ulong *)(unit[drive].trackbuf+(hdr.sec-1)*512))[3]);
return MFM_DATA;
}
}
return 0;
}
static inline ushort dos_encode_byte(unsigned char byte)
{
register unsigned char *enc, b2, b1;
register ushort word;
enc=mfmencode;
b1=byte;
b2=b1>>4;
b1&=15;
word=enc[b2] <<8 | enc [b1];
return (word|((word&(256|64)) ? 0: 128));
}
static void dos_encode_block(ushort *dest, unsigned char *src, int len)
{
int i;
for (i = 0; i < len; i++) {
*dest=dos_encode_byte(*src++);
*dest|=((dest[-1]&1)||(*dest&0x4000))? 0: 0x8000;
dest++;
}
}
static unsigned long *ms_putsec(int drive, unsigned long *raw, int cnt)
{
static struct dos_header hdr={0,0,0,2,0,
{78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78,78}};
int i;
static ushort crc[2]={0,0x4e4e};
drive&=3;
/* id gap 1 */
/* the MFM word before is always 9254 */
for(i=0;i<6;i++)
*raw++=0xaaaaaaaa;
/* 3 sync + 1 headermark */
*raw++=0x44894489;
*raw++=0x44895554;
/* fill in the variable parts of the header */
hdr.track=unit[drive].track/unit[drive].type->heads;
hdr.side=unit[drive].track%unit[drive].type->heads;
hdr.sec=cnt+1;
hdr.crc=dos_hdr_crc(&hdr);
/* header (without "magic") and id gap 2*/
dos_encode_block((ushort *)raw,(unsigned char *) &hdr.track,28);
raw+=14;
/*id gap 3 */
for(i=0;i<6;i++)
*raw++=0xaaaaaaaa;
/* 3 syncs and 1 datamark */
*raw++=0x44894489;
*raw++=0x44895545;
/* data */
dos_encode_block((ushort *)raw,
(unsigned char *)unit[drive].trackbuf+cnt*512,512);
raw+=256;
/*data crc + jd's special gap (long words :-/) */
crc[0]=dos_data_crc(unit[drive].trackbuf+cnt*512);
dos_encode_block((ushort *) raw,(unsigned char *)crc,4);
raw+=2;
/* data gap */
for(i=0;i<38;i++)
*raw++=0x92549254;
return raw; /* wrote 652 MFM words */
}
static void dos_write(int disk)
{
int cnt;
unsigned long raw = (unsigned long) raw_buf;
unsigned long *ptr=(unsigned long *)raw;
disk&=3;
/* really gap4 + indexgap , but we write it first and round it up */
for (cnt=0;cnt<425;cnt++)
*ptr++=0x92549254;
/* the following is just guessed */
if (unit[disk].type->sect_mult==2) /* check for HD-Disks */
for(cnt=0;cnt<473;cnt++)
*ptr++=0x92549254;
/* now the index marks...*/
for (cnt=0;cnt<20;cnt++)
*ptr++=0x92549254;
for (cnt=0;cnt<6;cnt++)
*ptr++=0xaaaaaaaa;
*ptr++=0x52245224;
*ptr++=0x52245552;
for (cnt=0;cnt<20;cnt++)
*ptr++=0x92549254;
/* sectors */
for(cnt = 0; cnt < unit[disk].dtype->sects * unit[disk].type->sect_mult; cnt++)
ptr=ms_putsec(disk,ptr,cnt);
*(ushort *)ptr = 0xaaa8; /* MFM word before is always 0x9254 */
}
/*
* Here comes the high level stuff (i.e. the filesystem interface)
* and helper functions.
* Normally this should be the only part that has to be adapted to
* different kernel versions.
*/
/* FIXME: this assumes the drive is still spinning -
* which is only true if we complete writing a track within three seconds
*/
static void flush_track_callback(struct timer_list *timer)
{
unsigned long nr = ((unsigned long)timer -
(unsigned long)&flush_track_timer[0]) /
sizeof(flush_track_timer[0]);
nr&=3;
writefromint = 1;
if (!try_fdc(nr)) {
/* we might block in an interrupt, so try again later */
flush_track_timer[nr].expires = jiffies + 1;
add_timer(flush_track_timer + nr);
return;
}
get_fdc(nr);
(*unit[nr].dtype->write_fkt)(nr);
if (!raw_write(nr)) {
printk (KERN_NOTICE "floppy disk write protected\n");
writefromint = 0;
writepending = 0;
}
rel_fdc();
}
static int non_int_flush_track (unsigned long nr)
{
unsigned long flags;
nr&=3;
writefromint = 0;
del_timer(&post_write_timer);
get_fdc(nr);
if (!fd_motor_on(nr)) {
writepending = 0;
rel_fdc();
return 0;
}
local_irq_save(flags);
if (writepending != 2) {
local_irq_restore(flags);
(*unit[nr].dtype->write_fkt)(nr);
if (!raw_write(nr)) {
printk (KERN_NOTICE "floppy disk write protected "
"in write!\n");
writepending = 0;
return 0;
}
wait_event(wait_fd_block, block_flag != 2);
}
else {
local_irq_restore(flags);
ms_delay(2); /* 2 ms post_write delay */
post_write(nr);
}
rel_fdc();
return 1;
}
static int get_track(int drive, int track)
{
int error, errcnt;
drive&=3;
if (unit[drive].track == track)
return 0;
get_fdc(drive);
if (!fd_motor_on(drive)) {
rel_fdc();
return -1;
}
if (unit[drive].dirty == 1) {
del_timer (flush_track_timer + drive);
non_int_flush_track (drive);
}
errcnt = 0;
while (errcnt < MAX_ERRORS) {
if (!fd_seek(drive, track))
return -1;
raw_read(drive);
error = (*unit[drive].dtype->read_fkt)(drive);
if (error == 0) {
rel_fdc();
return 0;
}
/* Read Error Handling: recalibrate and try again */
unit[drive].track = -1;
errcnt++;
}
rel_fdc();
return -1;
}
static blk_status_t amiflop_rw_cur_segment(struct amiga_floppy_struct *floppy,
struct request *rq)
{
int drive = floppy - unit;
unsigned int cnt, block, track, sector;
char *data;
for (cnt = 0; cnt < blk_rq_cur_sectors(rq); cnt++) {
#ifdef DEBUG
printk("fd: sector %ld + %d requested for %s\n",
blk_rq_pos(rq), cnt,
(rq_data_dir(rq) == READ) ? "read" : "write");
#endif
block = blk_rq_pos(rq) + cnt;
track = block / (floppy->dtype->sects * floppy->type->sect_mult);
sector = block % (floppy->dtype->sects * floppy->type->sect_mult);
data = bio_data(rq->bio) + 512 * cnt;
#ifdef DEBUG
printk("access to track %d, sector %d, with buffer at "
"0x%08lx\n", track, sector, data);
#endif
if (get_track(drive, track) == -1)
return BLK_STS_IOERR;
if (rq_data_dir(rq) == READ) {
memcpy(data, floppy->trackbuf + sector * 512, 512);
} else {
memcpy(floppy->trackbuf + sector * 512, data, 512);
/* keep the drive spinning while writes are scheduled */
if (!fd_motor_on(drive))
return BLK_STS_IOERR;
/*
* setup a callback to write the track buffer
* after a short (1 tick) delay.
*/
floppy->dirty = 1;
/* reset the timer */
mod_timer (flush_track_timer + drive, jiffies + 1);
}
}
return BLK_STS_OK;
}
static blk_status_t amiflop_queue_rq(struct blk_mq_hw_ctx *hctx,
const struct blk_mq_queue_data *bd)
{
struct request *rq = bd->rq;
struct amiga_floppy_struct *floppy = rq->rq_disk->private_data;
blk_status_t err;
if (!spin_trylock_irq(&amiflop_lock))
return BLK_STS_DEV_RESOURCE;
blk_mq_start_request(rq);
do {
err = amiflop_rw_cur_segment(floppy, rq);
} while (blk_update_request(rq, err, blk_rq_cur_bytes(rq)));
blk_mq_end_request(rq, err);
spin_unlock_irq(&amiflop_lock);
return BLK_STS_OK;
}
static int fd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
int drive = MINOR(bdev->bd_dev) & 3;
geo->heads = unit[drive].type->heads;
geo->sectors = unit[drive].dtype->sects * unit[drive].type->sect_mult;
geo->cylinders = unit[drive].type->tracks;
return 0;
}
static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode,
unsigned int cmd, unsigned long param)
{
struct amiga_floppy_struct *p = bdev->bd_disk->private_data;
int drive = p - unit;
static struct floppy_struct getprm;
void __user *argp = (void __user *)param;
switch(cmd){
case FDFMTBEG:
get_fdc(drive);
if (fd_ref[drive] > 1) {
rel_fdc();
return -EBUSY;
}
fsync_bdev(bdev);
if (fd_motor_on(drive) == 0) {
rel_fdc();
return -ENODEV;
}
if (fd_calibrate(drive) == 0) {
rel_fdc();
return -ENXIO;
}
floppy_off(drive);
rel_fdc();
break;
case FDFMTTRK:
if (param < p->type->tracks * p->type->heads)
{
get_fdc(drive);
if (fd_seek(drive,param) != 0){
memset(p->trackbuf, FD_FILL_BYTE,
p->dtype->sects * p->type->sect_mult * 512);
non_int_flush_track(drive);
}
floppy_off(drive);
rel_fdc();
}
else
return -EINVAL;
break;
case FDFMTEND:
floppy_off(drive);
invalidate_bdev(bdev);
break;
case FDGETPRM:
memset((void *)&getprm, 0, sizeof (getprm));
getprm.track=p->type->tracks;
getprm.head=p->type->heads;
getprm.sect=p->dtype->sects * p->type->sect_mult;
getprm.size=p->blocks;
if (copy_to_user(argp, &getprm, sizeof(struct floppy_struct)))
return -EFAULT;
break;
case FDSETPRM:
case FDDEFPRM:
return -EINVAL;
case FDFLUSH: /* unconditionally, even if not needed */
del_timer (flush_track_timer + drive);
non_int_flush_track(drive);
break;
#ifdef RAW_IOCTL
case IOCTL_RAW_TRACK:
if (copy_to_user(argp, raw_buf, p->type->read_size))
return -EFAULT;
else
return p->type->read_size;
#endif
default:
return -ENOSYS;
}
return 0;
}
static int fd_ioctl(struct block_device *bdev, fmode_t mode,
unsigned int cmd, unsigned long param)
{
int ret;
mutex_lock(&amiflop_mutex);
ret = fd_locked_ioctl(bdev, mode, cmd, param);
mutex_unlock(&amiflop_mutex);
return ret;
}
static void fd_probe(int dev)
{
unsigned long code;
int type;
int drive;
drive = dev & 3;
code = fd_get_drive_id(drive);
/* get drive type */
for (type = 0; type < num_dr_types; type++)
if (drive_types[type].code == code)
break;
if (type >= num_dr_types) {
printk(KERN_WARNING "fd_probe: unsupported drive type "
"%08lx found\n", code);
unit[drive].type = &drive_types[num_dr_types-1]; /* FD_NODRIVE */
return;
}
unit[drive].type = drive_types + type;
unit[drive].track = -1;
unit[drive].disk = -1;
unit[drive].motor = 0;
unit[drive].busy = 0;
unit[drive].status = -1;
}
/*
* floppy_open check for aliasing (/dev/fd0 can be the same as
* /dev/PS0 etc), and disallows simultaneous access to the same
* drive with different device numbers.
*/
static int floppy_open(struct block_device *bdev, fmode_t mode)
{
int drive = MINOR(bdev->bd_dev) & 3;
int system = (MINOR(bdev->bd_dev) & 4) >> 2;
int old_dev;
unsigned long flags;
mutex_lock(&amiflop_mutex);
old_dev = fd_device[drive];
if (fd_ref[drive] && old_dev != system) {
mutex_unlock(&amiflop_mutex);
return -EBUSY;
}
if (unit[drive].type->code == FD_NODRIVE) {
mutex_unlock(&amiflop_mutex);
return -ENXIO;
}
if (mode & (FMODE_READ|FMODE_WRITE)) {
bdev_check_media_change(bdev);
if (mode & FMODE_WRITE) {
int wrprot;
get_fdc(drive);
fd_select (drive);
wrprot = !(ciaa.pra & DSKPROT);
fd_deselect (drive);
rel_fdc();
if (wrprot) {
mutex_unlock(&amiflop_mutex);
return -EROFS;
}
}
}
local_irq_save(flags);
fd_ref[drive]++;
fd_device[drive] = system;
local_irq_restore(flags);
unit[drive].dtype=&data_types[system];
unit[drive].blocks=unit[drive].type->heads*unit[drive].type->tracks*
data_types[system].sects*unit[drive].type->sect_mult;
set_capacity(unit[drive].gendisk[system], unit[drive].blocks);
printk(KERN_INFO "fd%d: accessing %s-disk with %s-layout\n",drive,
unit[drive].type->name, data_types[system].name);
mutex_unlock(&amiflop_mutex);
return 0;
}
static void floppy_release(struct gendisk *disk, fmode_t mode)
{
struct amiga_floppy_struct *p = disk->private_data;
int drive = p - unit;
mutex_lock(&amiflop_mutex);
if (unit[drive].dirty == 1) {
del_timer (flush_track_timer + drive);
non_int_flush_track (drive);
}
if (!fd_ref[drive]--) {
printk(KERN_CRIT "floppy_release with fd_ref == 0");
fd_ref[drive] = 0;
}
#ifdef MODULE
floppy_off (drive);
#endif
mutex_unlock(&amiflop_mutex);
}
/*
* check_events is never called from an interrupt, so we can relax a bit
* here, sleep etc. Note that floppy-on tries to set current_DOR to point
* to the desired drive, but it will probably not survive the sleep if
* several floppies are used at the same time: thus the loop.
*/
static unsigned amiga_check_events(struct gendisk *disk, unsigned int clearing)
{
struct amiga_floppy_struct *p = disk->private_data;
int drive = p - unit;
int changed;
static int first_time = 1;
if (first_time)
changed = first_time--;
else {
get_fdc(drive);
fd_select (drive);
changed = !(ciaa.pra & DSKCHANGE);
fd_deselect (drive);
rel_fdc();
}
if (changed) {
fd_probe(drive);
p->track = -1;
p->dirty = 0;
writepending = 0; /* if this was true before, too bad! */
writefromint = 0;
return DISK_EVENT_MEDIA_CHANGE;
}
return 0;
}
static const struct block_device_operations floppy_fops = {
.owner = THIS_MODULE,
.open = floppy_open,
.release = floppy_release,
.ioctl = fd_ioctl,
.getgeo = fd_getgeo,
.check_events = amiga_check_events,
};
static const struct blk_mq_ops amiflop_mq_ops = {
.queue_rq = amiflop_queue_rq,
};
static int fd_alloc_disk(int drive, int system)
{
struct gendisk *disk;
disk = blk_mq_alloc_disk(&unit[drive].tag_set, NULL);
if (IS_ERR(disk))
return PTR_ERR(disk);
disk->major = FLOPPY_MAJOR;
disk->first_minor = drive + system;
disk->minors = 1;
disk->fops = &floppy_fops;
disk->events = DISK_EVENT_MEDIA_CHANGE;
if (system)
sprintf(disk->disk_name, "fd%d_msdos", drive);
else
sprintf(disk->disk_name, "fd%d", drive);
disk->private_data = &unit[drive];
set_capacity(disk, 880 * 2);
unit[drive].gendisk[system] = disk;
add_disk(disk);
return 0;
}
static int fd_alloc_drive(int drive)
{
unit[drive].trackbuf = kmalloc(FLOPPY_MAX_SECTORS * 512, GFP_KERNEL);
if (!unit[drive].trackbuf)
goto out;
memset(&unit[drive].tag_set, 0, sizeof(unit[drive].tag_set));
unit[drive].tag_set.ops = &amiflop_mq_ops;
unit[drive].tag_set.nr_hw_queues = 1;
unit[drive].tag_set.nr_maps = 1;
unit[drive].tag_set.queue_depth = 2;
unit[drive].tag_set.numa_node = NUMA_NO_NODE;
unit[drive].tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
if (blk_mq_alloc_tag_set(&unit[drive].tag_set))
goto out_cleanup_trackbuf;
pr_cont(" fd%d", drive);
if (fd_alloc_disk(drive, 0) || fd_alloc_disk(drive, 1))
goto out_cleanup_tagset;
return 0;
out_cleanup_tagset:
blk_mq_free_tag_set(&unit[drive].tag_set);
out_cleanup_trackbuf:
kfree(unit[drive].trackbuf);
out:
unit[drive].type->code = FD_NODRIVE;
return -ENOMEM;
}
static int __init fd_probe_drives(void)
{
int drive,drives,nomem;
pr_info("FD: probing units\nfound");
drives=0;
nomem=0;
for(drive=0;drive<FD_MAX_UNITS;drive++) {
fd_probe(drive);
if (unit[drive].type->code == FD_NODRIVE)
continue;
if (fd_alloc_drive(drive) < 0) {
pr_cont(" no mem for fd%d", drive);
nomem = 1;
continue;
}
drives++;
}
if ((drives > 0) || (nomem == 0)) {
if (drives == 0)
pr_cont(" no drives");
pr_cont("\n");
return drives;
}
pr_cont("\n");
return -ENOMEM;
}
static int __init amiga_floppy_probe(struct platform_device *pdev)
{
int i, ret;
if (register_blkdev(FLOPPY_MAJOR,"fd"))
return -EBUSY;
ret = -ENOMEM;
raw_buf = amiga_chip_alloc(RAW_BUF_SIZE, "Floppy");
if (!raw_buf) {
printk("fd: cannot get chip mem buffer\n");
goto out_blkdev;
}
ret = -EBUSY;
if (request_irq(IRQ_AMIGA_DSKBLK, fd_block_done, 0, "floppy_dma", NULL)) {
printk("fd: cannot get irq for dma\n");
goto out_irq;
}
if (request_irq(IRQ_AMIGA_CIAA_TB, ms_isr, 0, "floppy_timer", NULL)) {
printk("fd: cannot get irq for timer\n");
goto out_irq2;
}
ret = -ENODEV;
if (fd_probe_drives() < 1) /* No usable drives */
goto out_probe;
/* initialize variables */
timer_setup(&motor_on_timer, motor_on_callback, 0);
motor_on_timer.expires = 0;
for (i = 0; i < FD_MAX_UNITS; i++) {
timer_setup(&motor_off_timer[i], fd_motor_off, 0);
motor_off_timer[i].expires = 0;
timer_setup(&flush_track_timer[i], flush_track_callback, 0);
flush_track_timer[i].expires = 0;
unit[i].track = -1;
}
timer_setup(&post_write_timer, post_write_callback, 0);
post_write_timer.expires = 0;
for (i = 0; i < 128; i++)
mfmdecode[i]=255;
for (i = 0; i < 16; i++)
mfmdecode[mfmencode[i]]=i;
/* make sure that disk DMA is enabled */
custom.dmacon = DMAF_SETCLR | DMAF_DISK;
/* init ms timer */
ciaa.crb = 8; /* one-shot, stop */
return 0;
out_probe:
free_irq(IRQ_AMIGA_CIAA_TB, NULL);
out_irq2:
free_irq(IRQ_AMIGA_DSKBLK, NULL);
out_irq:
amiga_chip_free(raw_buf);
out_blkdev:
unregister_blkdev(FLOPPY_MAJOR,"fd");
return ret;
}
static struct platform_driver amiga_floppy_driver = {
.driver = {
.name = "amiga-floppy",
},
};
static int __init amiga_floppy_init(void)
{
return platform_driver_probe(&amiga_floppy_driver, amiga_floppy_probe);
}
module_init(amiga_floppy_init);
#ifndef MODULE
static int __init amiga_floppy_setup (char *str)
{
int n;
if (!MACH_IS_AMIGA)
return 0;
if (!get_option(&str, &n))
return 0;
printk (KERN_INFO "amiflop: Setting default df0 to %x\n", n);
fd_def_df0 = n;
return 1;
}
__setup("floppy=", amiga_floppy_setup);
#endif
MODULE_ALIAS("platform:amiga-floppy");
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