/* * 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 = 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 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_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_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 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, .getgeo = fd_getgeo, .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 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