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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/block/amiflop.c
downloadop-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
op-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/block/amiflop.c')
-rw-r--r--drivers/block/amiflop.c1850
1 files changed, 1850 insertions, 0 deletions
diff --git a/drivers/block/amiflop.c b/drivers/block/amiflop.c
new file mode 100644
index 0000000..1468e8c
--- /dev/null
+++ b/drivers/block/amiflop.c
@@ -0,0 +1,1850 @@
+/*
+ * 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/fd.h>
+#include <linux/hdreg.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/amifdreg.h>
+#include <linux/amifd.h>
+#include <linux/buffer_head.h>
+#include <linux/blkdev.h>
+#include <linux/elevator.h>
+
+#include <asm/setup.h>
+#include <asm/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
+ */
+
+/*
+ * 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 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");
+
+static struct request_queue *floppy_queue;
+#define QUEUE (floppy_queue)
+#define CURRENT elv_next_request(floppy_queue)
+
+/*
+ * 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 = sizeof(drive_types) / sizeof(drive_types[0]);
+
+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 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_WAIT_QUEUE_HEAD(motor_wait);
+
+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 volatile int ms_busy = -1;
+static DECLARE_WAIT_QUEUE_HEAD(ms_wait);
+#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
+
+/* 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, struct pt_regs *fp)
+{
+ ms_busy = -1;
+ wake_up(&ms_wait);
+ 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)
+{
+ unsigned long flags;
+ int ticks;
+ if (ms > 0) {
+ local_irq_save(flags);
+ while (ms_busy == 0)
+ sleep_on(&ms_wait);
+ ms_busy = 0;
+ local_irq_restore(flags);
+ ticks = MS_TICKS*ms-1;
+ ciaa.tblo=ticks%256;
+ ciaa.tbhi=ticks/256;
+ ciaa.crb=0x19; /*count eclock, force load, one-shoot, start */
+ sleep_on(&ms_wait);
+ }
+}
+
+/* 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);
+ while (!try_fdc(drive))
+ sleep_on(&fdc_wait);
+ 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(unsigned long nr)
+{
+ if (!(ciaa.pra & DSKRDY) || --on_attempts == 0) {
+ wake_up (&motor_wait);
+ } 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);
+
+ motor_on_timer.data = nr;
+ mod_timer(&motor_on_timer, jiffies + HZ/2);
+
+ on_attempts = 10;
+ sleep_on (&motor_wait);
+ 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 (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(unsigned long drive)
+{
+ long calledfromint;
+#ifdef MODULE
+ long decusecount;
+
+ decusecount = drive & 0x40000000;
+#endif
+ calledfromint = drive & 0x80000000;
+ drive&=3;
+ if (calledfromint && !try_fdc(drive)) {
+ /* We would be blocked in an interrupt, so try again later */
+ motor_off_timer[drive].expires = jiffies + 1;
+ add_timer(motor_off_timer + drive);
+ 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;
+ /* called this way it is always from interrupt */
+ motor_off_timer[drive].data = nr | 0x80000000;
+ 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 (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, struct pt_regs *fp)
+{
+ 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.data = 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);
+ while (block_flag)
+ sleep_on(&wait_fd_block);
+ 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;
+
+ while (block_flag)
+ sleep_on (&wait_fd_block);
+
+ 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;
+ }
+ while (block_flag)
+ sleep_on(&wait_fd_block);
+ 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 */
+}
+
+
+/*
+ * 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(unsigned long nr)
+{
+ 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;
+ }
+ while (block_flag == 2)
+ sleep_on (&wait_fd_block);
+ }
+ 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 void redo_fd_request(void)
+{
+ unsigned int cnt, block, track, sector;
+ int drive;
+ struct amiga_floppy_struct *floppy;
+ char *data;
+ unsigned long flags;
+
+ repeat:
+ if (!CURRENT) {
+ /* Nothing left to do */
+ return;
+ }
+
+ floppy = CURRENT->rq_disk->private_data;
+ drive = floppy - unit;
+
+ /* Here someone could investigate to be more efficient */
+ for (cnt = 0; cnt < CURRENT->current_nr_sectors; cnt++) {
+#ifdef DEBUG
+ printk("fd: sector %ld + %d requested for %s\n",
+ CURRENT->sector,cnt,
+ (CURRENT->cmd==READ)?"read":"write");
+#endif
+ block = CURRENT->sector + cnt;
+ if ((int)block > floppy->blocks) {
+ end_request(CURRENT, 0);
+ goto repeat;
+ }
+
+ track = block / (floppy->dtype->sects * floppy->type->sect_mult);
+ sector = block % (floppy->dtype->sects * floppy->type->sect_mult);
+ data = CURRENT->buffer + 512 * cnt;
+#ifdef DEBUG
+ printk("access to track %d, sector %d, with buffer at "
+ "0x%08lx\n", track, sector, data);
+#endif
+
+ if ((rq_data_dir(CURRENT) != READ) && (rq_data_dir(CURRENT) != WRITE)) {
+ printk(KERN_WARNING "do_fd_request: unknown command\n");
+ end_request(CURRENT, 0);
+ goto repeat;
+ }
+ if (get_track(drive, track) == -1) {
+ end_request(CURRENT, 0);
+ goto repeat;
+ }
+
+ switch (rq_data_dir(CURRENT)) {
+ case READ:
+ memcpy(data, floppy->trackbuf + sector * 512, 512);
+ break;
+
+ case WRITE:
+ memcpy(floppy->trackbuf + sector * 512, data, 512);
+
+ /* keep the drive spinning while writes are scheduled */
+ if (!fd_motor_on(drive)) {
+ end_request(CURRENT, 0);
+ goto repeat;
+ }
+ /*
+ * setup a callback to write the track buffer
+ * after a short (1 tick) delay.
+ */
+ local_irq_save(flags);
+
+ floppy->dirty = 1;
+ /* reset the timer */
+ mod_timer (flush_track_timer + drive, jiffies + 1);
+ local_irq_restore(flags);
+ break;
+ }
+ }
+ CURRENT->nr_sectors -= CURRENT->current_nr_sectors;
+ CURRENT->sector += CURRENT->current_nr_sectors;
+
+ end_request(CURRENT, 1);
+ goto repeat;
+}
+
+static void do_fd_request(request_queue_t * q)
+{
+ redo_fd_request();
+}
+
+static int fd_ioctl(struct inode *inode, struct file *filp,
+ unsigned int cmd, unsigned long param)
+{
+ int drive = iminor(inode) & 3;
+ static struct floppy_struct getprm;
+
+ switch(cmd){
+ case HDIO_GETGEO:
+ {
+ struct hd_geometry loc;
+ loc.heads = unit[drive].type->heads;
+ loc.sectors = unit[drive].dtype->sects * unit[drive].type->sect_mult;
+ loc.cylinders = unit[drive].type->tracks;
+ loc.start = 0;
+ if (copy_to_user((void *)param, (void *)&loc,
+ sizeof(struct hd_geometry)))
+ return -EFAULT;
+ break;
+ }
+ case FDFMTBEG:
+ get_fdc(drive);
+ if (fd_ref[drive] > 1) {
+ rel_fdc();
+ return -EBUSY;
+ }
+ fsync_bdev(inode->i_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 < unit[drive].type->tracks * unit[drive].type->heads)
+ {
+ get_fdc(drive);
+ if (fd_seek(drive,param) != 0){
+ memset(unit[drive].trackbuf, FD_FILL_BYTE,
+ unit[drive].dtype->sects * unit[drive].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(inode->i_bdev, 0);
+ break;
+ case FDGETPRM:
+ memset((void *)&getprm, 0, sizeof (getprm));
+ getprm.track=unit[drive].type->tracks;
+ getprm.head=unit[drive].type->heads;
+ getprm.sect=unit[drive].dtype->sects * unit[drive].type->sect_mult;
+ getprm.size=unit[drive].blocks;
+ if (copy_to_user((void *)param,
+ (void *)&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((void *)param, raw_buf,
+ unit[drive].type->read_size))
+ return -EFAULT;
+ else
+ return unit[drive].type->read_size;
+#endif
+ default:
+ printk(KERN_DEBUG "fd_ioctl: unknown cmd %d for drive %d.",
+ cmd, drive);
+ return -ENOSYS;
+ }
+ return 0;
+}
+
+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 inode *inode, struct file *filp)
+{
+ int drive = iminor(inode) & 3;
+ int system = (iminor(inode) & 4) >> 2;
+ int old_dev;
+ unsigned long flags;
+
+ old_dev = fd_device[drive];
+
+ if (fd_ref[drive] && old_dev != system)
+ return -EBUSY;
+
+ if (filp && filp->f_mode & 3) {
+ check_disk_change(inode->i_bdev);
+ if (filp->f_mode & 2 ) {
+ int wrprot;
+
+ get_fdc(drive);
+ fd_select (drive);
+ wrprot = !(ciaa.pra & DSKPROT);
+ fd_deselect (drive);
+ rel_fdc();
+
+ if (wrprot)
+ 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, unit[drive].blocks);
+
+ printk(KERN_INFO "fd%d: accessing %s-disk with %s-layout\n",drive,
+ unit[drive].type->name, data_types[system].name);
+
+ return 0;
+}
+
+static int floppy_release(struct inode * inode, struct file * filp)
+{
+ int drive = iminor(inode) & 3;
+
+ 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
+/* the mod_use counter is handled this way */
+ floppy_off (drive | 0x40000000);
+#endif
+ return 0;
+}
+
+/*
+ * floppy-change 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 int amiga_floppy_change(struct gendisk *disk)
+{
+ 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 1;
+ }
+ return 0;
+}
+
+static struct block_device_operations floppy_fops = {
+ .owner = THIS_MODULE,
+ .open = floppy_open,
+ .release = floppy_release,
+ .ioctl = fd_ioctl,
+ .media_changed = amiga_floppy_change,
+};
+
+void __init amiga_floppy_setup (char *str, int *ints)
+{
+ printk (KERN_INFO "amiflop: Setting default df0 to %x\n", ints[1]);
+ fd_def_df0 = ints[1];
+}
+
+static int __init fd_probe_drives(void)
+{
+ int drive,drives,nomem;
+
+ printk(KERN_INFO "FD: probing units\n" KERN_INFO "found ");
+ drives=0;
+ nomem=0;
+ for(drive=0;drive<FD_MAX_UNITS;drive++) {
+ struct gendisk *disk;
+ fd_probe(drive);
+ if (unit[drive].type->code == FD_NODRIVE)
+ continue;
+ disk = alloc_disk(1);
+ if (!disk) {
+ unit[drive].type->code = FD_NODRIVE;
+ continue;
+ }
+ unit[drive].gendisk = disk;
+ drives++;
+ if ((unit[drive].trackbuf = kmalloc(FLOPPY_MAX_SECTORS * 512, GFP_KERNEL)) == NULL) {
+ printk("no mem for ");
+ unit[drive].type = &drive_types[num_dr_types - 1]; /* FD_NODRIVE */
+ drives--;
+ nomem = 1;
+ }
+ printk("fd%d ",drive);
+ disk->major = FLOPPY_MAJOR;
+ disk->first_minor = drive;
+ disk->fops = &floppy_fops;
+ sprintf(disk->disk_name, "fd%d", drive);
+ disk->private_data = &unit[drive];
+ disk->queue = floppy_queue;
+ set_capacity(disk, 880*2);
+ add_disk(disk);
+ }
+ if ((drives > 0) || (nomem == 0)) {
+ if (drives == 0)
+ printk("no drives");
+ printk("\n");
+ return drives;
+ }
+ printk("\n");
+ return -ENOMEM;
+}
+
+static struct kobject *floppy_find(dev_t dev, int *part, void *data)
+{
+ int drive = *part & 3;
+ if (unit[drive].type->code == FD_NODRIVE)
+ return NULL;
+ *part = 0;
+ return get_disk(unit[drive].gendisk);
+}
+
+int __init amiga_floppy_init(void)
+{
+ int i, ret;
+
+ if (!AMIGAHW_PRESENT(AMI_FLOPPY))
+ return -ENXIO;
+
+ if (register_blkdev(FLOPPY_MAJOR,"fd"))
+ return -EBUSY;
+
+ /*
+ * We request DSKPTR, DSKLEN and DSKDATA only, because the other
+ * floppy registers are too spreaded over the custom register space
+ */
+ ret = -EBUSY;
+ if (!request_mem_region(CUSTOM_PHYSADDR+0x20, 8, "amiflop [Paula]")) {
+ printk("fd: cannot get floppy registers\n");
+ goto out_blkdev;
+ }
+
+ ret = -ENOMEM;
+ if ((raw_buf = (char *)amiga_chip_alloc (RAW_BUF_SIZE, "Floppy")) ==
+ NULL) {
+ printk("fd: cannot get chip mem buffer\n");
+ goto out_memregion;
+ }
+
+ 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 = -ENOMEM;
+ floppy_queue = blk_init_queue(do_fd_request, &amiflop_lock);
+ if (!floppy_queue)
+ goto out_queue;
+
+ ret = -ENXIO;
+ if (fd_probe_drives() < 1) /* No usable drives */
+ goto out_probe;
+
+ blk_register_region(MKDEV(FLOPPY_MAJOR, 0), 256, THIS_MODULE,
+ floppy_find, NULL, NULL);
+
+ /* initialize variables */
+ init_timer(&motor_on_timer);
+ motor_on_timer.expires = 0;
+ motor_on_timer.data = 0;
+ motor_on_timer.function = motor_on_callback;
+ for (i = 0; i < FD_MAX_UNITS; i++) {
+ init_timer(&motor_off_timer[i]);
+ motor_off_timer[i].expires = 0;
+ motor_off_timer[i].data = i|0x80000000;
+ motor_off_timer[i].function = fd_motor_off;
+ init_timer(&flush_track_timer[i]);
+ flush_track_timer[i].expires = 0;
+ flush_track_timer[i].data = i;
+ flush_track_timer[i].function = flush_track_callback;
+
+ unit[i].track = -1;
+ }
+
+ init_timer(&post_write_timer);
+ post_write_timer.expires = 0;
+ post_write_timer.data = 0;
+ post_write_timer.function = post_write;
+
+ 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:
+ blk_cleanup_queue(floppy_queue);
+out_queue:
+ free_irq(IRQ_AMIGA_CIAA_TB, NULL);
+out_irq2:
+ free_irq(IRQ_AMIGA_DSKBLK, NULL);
+out_irq:
+ amiga_chip_free(raw_buf);
+out_memregion:
+ release_mem_region(CUSTOM_PHYSADDR+0x20, 8);
+out_blkdev:
+ unregister_blkdev(FLOPPY_MAJOR,"fd");
+ return ret;
+}
+
+#ifdef MODULE
+#include <linux/version.h>
+
+int init_module(void)
+{
+ if (!MACH_IS_AMIGA)
+ return -ENXIO;
+ return amiga_floppy_init();
+}
+
+#if 0 /* not safe to unload */
+void cleanup_module(void)
+{
+ int i;
+
+ for( i = 0; i < FD_MAX_UNITS; i++) {
+ if (unit[i].type->code != FD_NODRIVE) {
+ del_gendisk(unit[i].gendisk);
+ put_disk(unit[i].gendisk);
+ kfree(unit[i].trackbuf);
+ }
+ }
+ blk_unregister_region(MKDEV(FLOPPY_MAJOR, 0), 256);
+ free_irq(IRQ_AMIGA_CIAA_TB, NULL);
+ free_irq(IRQ_AMIGA_DSKBLK, NULL);
+ custom.dmacon = DMAF_DISK; /* disable DMA */
+ amiga_chip_free(raw_buf);
+ blk_cleanup_queue(floppy_queue);
+ release_mem_region(CUSTOM_PHYSADDR+0x20, 8);
+ unregister_blkdev(FLOPPY_MAJOR, "fd");
+}
+#endif
+#endif
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