2 * linux/drivers/acorn/block/mfmhd.c
4 * Copyright (C) 1995, 1996 Russell King, Dave Alan Gilbert (gilbertd@cs.man.ac.uk)
6 * MFM hard drive code [experimental]
12 * 3/2/96:DAG: Started a change list :-)
13 * Set the hardsect_size pointers up since we are running 256 byte
15 * Added DMA code, put it into the rw_intr
16 * Moved RCAL out of generic interrupt code - don't want to do it
17 * while DMA'ing - its now in individual handlers.
18 * Took interrupt handlers off task queue lists and called
19 * directly - not sure of implications.
21 * 18/2/96:DAG: Well its reading OK I think, well enough for image file code
22 * to find the image file; but now I've discovered that I actually
23 * have to put some code in for image files.
25 * Added stuff for image files; seems to work, but I've not
26 * got a multisegment image file (I don't think!).
27 * Put in a hack (yep a real hack) for multiple cylinder reads.
28 * Not convinced its working.
30 * 5/4/96:DAG: Added asm/hardware.h and use IOC_ macros
31 * Rewrote dma code in mfm.S (again!) - now takes a word at a time
32 * from main RAM for speed; still doesn't feel speedy!
34 * 20/4/96:DAG: After rewriting mfm.S a heck of a lot of times and speeding
35 * things up, I've finally figured out why its so damn slow.
36 * Linux is only reading a block at a time, and so you never
37 * get more than 1K per disc revoloution ~=60K/second.
39 * 27/4/96:DAG: On Russell's advice I change ll_rw_blk.c to ask it to
40 * join adjacent blocks together. Everything falls flat on its
42 * Four hours of debugging later; I hadn't realised that
43 * ll_rw_blk would be so generous as to join blocks whose
44 * results aren't going into consecutive buffers.
46 * OK; severe rehacking of mfm_rw_interrupt; now end_request's
47 * as soon as its DMA'd each request. Odd thing is that
48 * we are sometimes getting interrupts where we are not transferring
49 * any data; why? Is that what happens when you miss? I doubt
50 * it; are we too fast? No - its just at command ends. Got 240K/s
51 * better than before, but RiscOS hits 480K/s
53 * 25/6/96:RMK: Fixed init code to allow the MFM podule to work. Increased the
54 * number of errors for my Miniscribe drive (8425).
56 * 30/6/96:DAG: Russell suggested that a check drive 0 might turn the LEDs off
57 * - so in request_done just before it clears Busy it sends a
58 * check drive 0 - and the LEDs go off!!!!
60 * Added test for mainboard controller. - Removes need for separate
63 * 13/7/96:DAG: Changed hardware sectore size to 512 in attempt to make
65 * 21/7/96:DAG: Took out old image file stuff (accessing it now produces an IO
68 * 17/8/96:DAG: Ran through indent -kr -i8; evil - all my nice 2 character indents
69 * gone :-( Hand modified afterwards.
70 * Took out last remains of the older image map system.
72 * 22/9/96:DAG: Changed mfm.S so it will carry on DMA'ing til; BSY is dropped
73 * Changed mfm_rw_intr so that it doesn't follow the error
74 * code until BSY is dropped. Nope - still broke. Problem
75 * may revolve around when it reads the results for the error
78 *16/11/96:DAG: Modified for 2.0.18; request_irq changed
80 *17/12/96:RMK: Various cleanups, reorganisation, and the changes for new IO system.
81 * Improved probe for onboard MFM chip - it was hanging on my A5k.
82 * Added autodetect CHS code such that we don't rely on the presence
83 * of an ADFS boot block. Added ioport resource manager calls so
84 * that we don't clash with already-running hardware (eg. RiscPC Ether
85 * card slots if someone tries this)!
87 * 17/1/97:RMK: Upgraded to 2.1 kernels.
89 * 4/3/98:RMK: Changed major number to 21.
91 * 27/6/98:RMK: Changed asm/delay.h to linux/delay.h for mdelay().
95 * Possible enhancements:
96 * Multi-thread the code so that it is possible that while one drive
97 * is seeking, the other one can be reading data/seeking as well.
98 * This would be a performance boost with dual drive systems.
101 #include <linux/module.h>
102 #include <linux/fs.h>
103 #include <linux/interrupt.h>
104 #include <linux/kernel.h>
105 #include <linux/timer.h>
106 #include <linux/mm.h>
107 #include <linux/errno.h>
108 #include <linux/genhd.h>
109 #include <linux/major.h>
110 #include <linux/ioport.h>
111 #include <linux/delay.h>
112 #include <linux/blkpg.h>
114 #include <asm/system.h>
117 #include <asm/uaccess.h>
119 #include <asm/hardware.h>
120 #include <asm/ecard.h>
121 #include <asm/hardware/ioc.h>
123 static void (*do_mfm)(void) = NULL;
124 static struct request_queue *mfm_queue;
125 static DEFINE_SPINLOCK(mfm_lock);
127 #define MAJOR_NR MFM_ACORN_MAJOR
128 #define QUEUE (mfm_queue)
129 #define CURRENT elv_next_request(mfm_queue)
132 * Configuration section
134 * This is the maximum number of drives that we accept
136 #define MFM_MAXDRIVES 2
138 * Linux I/O address of onboard MFM controller or 0 to disable this
140 #define ONBOARD_MFM_ADDRESS ((0x002d0000 >> 2) | 0x80000000)
142 * Uncomment this to enable debugging in the MFM driver...
148 * End of configuration
153 * This structure contains all information to do with a particular physical
157 unsigned char sectors;
159 unsigned short cylinders;
160 unsigned short lowcurrent;
161 unsigned short precomp;
163 #define NEED_1_RECAL -2
164 #define NEED_2_RECAL -3
171 } mfm_info[MFM_MAXDRIVES];
173 #define MFM_DRV_INFO mfm_info[raw_cmd.dev]
175 /* Stuff from the assembly routines */
176 extern unsigned int hdc63463_baseaddress; /* Controller base address */
177 extern unsigned int hdc63463_irqpolladdress; /* Address to read to test for int */
178 extern unsigned int hdc63463_irqpollmask; /* Mask for irq register */
179 extern unsigned int hdc63463_dataptr; /* Pointer to kernel data space to DMA */
180 extern int hdc63463_dataleft; /* Number of bytes left to transfer */
185 static int lastspecifieddrive;
186 static unsigned Busy;
188 static unsigned int PartFragRead; /* The number of sectors which have been read
189 during a partial read split over two
190 cylinders. If 0 it means a partial
191 read did not occur. */
193 static unsigned int PartFragRead_RestartBlock; /* Where to restart on a split access */
194 static unsigned int PartFragRead_SectorsLeft; /* Where to restart on a split access */
196 static int Sectors256LeftInCurrent; /* i.e. 256 byte sectors left in current */
197 static int SectorsLeftInRequest; /* i.e. blocks left in the thing mfm_request was called for */
198 static int Copy_Sector; /* The 256 byte sector we are currently at - fragments need to know
199 where to take over */
200 static char *Copy_buffer;
203 static void mfm_seek(void);
204 static void mfm_rerequest(void);
205 static void mfm_request(void);
206 static void mfm_specify (void);
207 static void issue_request(unsigned int block, unsigned int nsect,
208 struct request *req);
210 static unsigned int mfm_addr; /* Controller address */
211 static unsigned int mfm_IRQPollLoc; /* Address to read for IRQ information */
212 static unsigned int mfm_irqenable; /* Podule IRQ enable location */
213 static unsigned char mfm_irq; /* Interrupt number */
214 static int mfm_drives = 0; /* drives available */
215 static int mfm_status = 0; /* interrupt status */
218 static struct rawcmd {
220 unsigned int cylinder;
223 unsigned int cmdtype;
224 unsigned int cmdcode;
225 unsigned char cmddata[16];
229 static unsigned char result[16];
232 void (*interrupt) (void); /* interrupt handler */
233 void (*error) (void); /* error handler */
234 void (*redo) (void); /* redo handler */
235 void (*done) (int st); /* done handler */
239 static struct tq_struct mfm_tq = {0, 0, (void (*)(void *)) NULL, 0};
242 int number_mfm_drives = 1;
244 /* ------------------------------------------------------------------------------------------ */
246 * From the HD63463 data sheet from Hitachi Ltd.
249 #define MFM_COMMAND (mfm_addr + 0)
250 #define MFM_DATAOUT (mfm_addr + 1)
251 #define MFM_STATUS (mfm_addr + 8)
252 #define MFM_DATAIN (mfm_addr + 9)
254 #define CMD_ABT 0xF0 /* Abort */
255 #define CMD_SPC 0xE8 /* Specify */
256 #define CMD_TST 0xE0 /* Test */
257 #define CMD_RCLB 0xC8 /* Recalibrate */
258 #define CMD_SEK 0xC0 /* Seek */
259 #define CMD_WFS 0xAB /* Write Format Skew */
260 #define CMD_WFM 0xA3 /* Write Format */
261 #define CMD_MTB 0x90 /* Memory to buffer */
262 #define CMD_CMPD 0x88 /* Compare data */
263 #define CMD_WD 0x87 /* Write data */
264 #define CMD_RED 0x70 /* Read erroneous data */
265 #define CMD_RIS 0x68 /* Read ID skew */
266 #define CMD_FID 0x61 /* Find ID */
267 #define CMD_RID 0x60 /* Read ID */
268 #define CMD_BTM 0x50 /* Buffer to memory */
269 #define CMD_CKD 0x48 /* Check data */
270 #define CMD_RD 0x40 /* Read data */
271 #define CMD_OPBW 0x38 /* Open buffer write */
272 #define CMD_OPBR 0x30 /* Open buffer read */
273 #define CMD_CKV 0x28 /* Check drive */
274 #define CMD_CKE 0x20 /* Check ECC */
275 #define CMD_POD 0x18 /* Polling disable */
276 #define CMD_POL 0x10 /* Polling enable */
277 #define CMD_RCAL 0x08 /* Recall */
279 #define STAT_BSY 0x8000 /* Busy */
280 #define STAT_CPR 0x4000 /* Command Parameter Rejection */
281 #define STAT_CED 0x2000 /* Command end */
282 #define STAT_SED 0x1000 /* Seek end */
283 #define STAT_DER 0x0800 /* Drive error */
284 #define STAT_ABN 0x0400 /* Abnormal end */
285 #define STAT_POL 0x0200 /* Polling */
287 /* ------------------------------------------------------------------------------------------ */
289 static void console_printf(const char *fmt,...)
291 static char buffer[2048]; /* Arbitary! */
292 extern void console_print(const char *);
296 local_irq_save(flags);
299 vsprintf(buffer, fmt, ap);
300 console_print(buffer);
303 local_irq_restore(flags);
304 }; /* console_printf */
306 #define DBG(x...) console_printf(x)
311 static void print_status(void)
314 static char *errors[] = {
331 "data field EEC error",
332 "data field CRC error",
334 "data field fatal error",
337 "ID field CRC error",
342 if (result[1] < 0x65)
343 error = errors[result[1] >> 2];
347 if (mfm_status & STAT_BSY) printk("BSY ");
348 if (mfm_status & STAT_CPR) printk("CPR ");
349 if (mfm_status & STAT_CED) printk("CED ");
350 if (mfm_status & STAT_SED) printk("SED ");
351 if (mfm_status & STAT_DER) printk("DER ");
352 if (mfm_status & STAT_ABN) printk("ABN ");
353 if (mfm_status & STAT_POL) printk("POL ");
354 printk(") SSB = %X (%s)\n", result[1], error);
358 /* ------------------------------------------------------------------------------------- */
360 static void issue_command(int command, unsigned char *cmdb, int len)
365 console_printf("issue_command: %02X: ", command);
366 for (i = 0; i < len; i++)
367 console_printf("%02X ", cmdb[i]);
368 console_printf("\n");
372 status = inw(MFM_STATUS);
373 } while (status & (STAT_BSY | STAT_POL));
374 DBG("issue_command: status after pol/bsy loop: %02X:\n ", status >> 8);
376 if (status & (STAT_CPR | STAT_CED | STAT_SED | STAT_DER | STAT_ABN)) {
377 outw(CMD_RCAL, MFM_COMMAND);
378 while (inw(MFM_STATUS) & STAT_BSY);
380 status = inw(MFM_STATUS);
381 DBG("issue_command: status before parameter issue: %02X:\n ", status >> 8);
384 outw(cmdb[1] | (cmdb[0] << 8), MFM_DATAOUT);
388 status = inw(MFM_STATUS);
389 DBG("issue_command: status before command issue: %02X:\n ", status >> 8);
391 outw(command, MFM_COMMAND);
392 status = inw(MFM_STATUS);
393 DBG("issue_command: status immediately after command issue: %02X:\n ", status >> 8);
396 static void wait_for_completion(void)
398 while ((mfm_status = inw(MFM_STATUS)) & STAT_BSY);
401 static void wait_for_command_end(void)
405 while (!((mfm_status = inw(MFM_STATUS)) & STAT_CED));
407 for (i = 0; i < 16;) {
409 in = inw(MFM_DATAIN);
410 result[i++] = in >> 8;
413 outw (CMD_RCAL, MFM_COMMAND);
416 /* ------------------------------------------------------------------------------------- */
418 static void mfm_rw_intr(void)
420 int old_status; /* Holds status on entry, we read to see if the command just finished */
422 console_printf("mfm_rw_intr...dataleft=%d\n", hdc63463_dataleft);
426 /* Now don't handle the error until BSY drops */
427 if ((mfm_status & (STAT_DER | STAT_ABN)) && ((mfm_status&STAT_BSY)==0)) {
428 /* Something has gone wrong - let's try that again */
429 outw(CMD_RCAL, MFM_COMMAND); /* Clear interrupt condition */
431 DBG("mfm_rw_intr: DER/ABN err\n");
438 /* OK so what ever happened it's not an error, now I reckon we are left between
439 a choice of command end or some data which is ready to be collected */
440 /* I think we have to transfer data while the interrupt line is on and its
441 not any other type of interrupt */
442 if (CURRENT->cmd == WRITE) {
443 extern void hdc63463_writedma(void);
444 if ((hdc63463_dataleft <= 0) && (!(mfm_status & STAT_CED))) {
445 printk("mfm_rw_intr: Apparent DMA write request when no more to DMA\n");
454 extern void hdc63463_readdma(void);
455 if ((hdc63463_dataleft <= 0) && (!(mfm_status & STAT_CED))) {
456 printk("mfm_rw_intr: Apparent DMA read request when no more to DMA\n");
463 DBG("Going to try read dma..............status=0x%x, buffer=%p\n", mfm_status, hdc63463_dataptr);
467 if (hdc63463_dataptr != ((unsigned int) Copy_buffer + 256)) {
468 /* If we didn't actually manage to get any data on this interrupt - but why? We got the interrupt */
469 /* Ah - well looking at the status its just when we get command end; so no problem */
470 /*console_printf("mfm: dataptr mismatch. dataptr=0x%08x Copy_buffer+256=0x%08p\n",
471 hdc63463_dataptr,Copy_buffer+256);
474 Sectors256LeftInCurrent--;
478 /* We have come to the end of this request */
479 if (!Sectors256LeftInCurrent) {
480 DBG("mfm: end_request for CURRENT=0x%p CURRENT(sector=%d current_nr_sectors=%d nr_sectors=%d)\n",
481 CURRENT, CURRENT->sector, CURRENT->current_nr_sectors, CURRENT->nr_sectors);
483 CURRENT->nr_sectors -= CURRENT->current_nr_sectors;
484 CURRENT->sector += CURRENT->current_nr_sectors;
485 SectorsLeftInRequest -= CURRENT->current_nr_sectors;
487 end_request(CURRENT, 1);
488 if (SectorsLeftInRequest) {
489 hdc63463_dataptr = (unsigned int) CURRENT->buffer;
490 Copy_buffer = CURRENT->buffer;
491 Sectors256LeftInCurrent = CURRENT->current_nr_sectors * 2;
492 errors = &(CURRENT->errors);
493 /* These should match the present calculations of the next logical sector
495 Copy_Sector=CURRENT->sector*2; */
497 if (Copy_Sector != CURRENT->sector * 2)
499 /*console_printf*/printk("mfm: Copy_Sector mismatch. Copy_Sector=%d CURRENT->sector*2=%d\n",
500 Copy_Sector, CURRENT->sector * 2);
502 printk("mfm: Copy_Sector mismatch! Eek!\n");
505 }; /* Sectors256LeftInCurrent */
508 old_status = mfm_status;
509 mfm_status = inw(MFM_STATUS);
510 if (mfm_status & (STAT_DER | STAT_ABN)) {
511 /* Something has gone wrong - let's try that again */
513 DBG("mfm_rw_intr: DER/ABN error\n");
520 /* If this code wasn't entered due to command_end but there is
521 now a command end we must read the command results out. If it was
522 entered like this then mfm_interrupt_handler would have done the
524 if ((!((old_status & (STAT_CPR | STAT_BSY)) == STAT_CPR)) &&
525 ((mfm_status & (STAT_CPR | STAT_BSY)) == STAT_CPR)) {
529 in = inw(MFM_DATAIN);
530 result[len++] = in >> 8;
535 /*console_printf ("mfm_rw_intr nearexit [%02X]\n", __raw_readb(mfm_IRQPollLoc)); */
537 /* If end of command move on */
538 if (mfm_status & (STAT_CED)) {
539 outw(CMD_RCAL, MFM_COMMAND); /* Clear interrupt condition */
540 /* End of command - trigger the next command */
544 DBG("mfm_rw_intr: returned from cont->done\n");
546 /* Its going to generate another interrupt */
547 do_mfm = mfm_rw_intr;
551 static void mfm_setup_rw(void)
553 DBG("setting up for rw...\n");
555 do_mfm = mfm_rw_intr;
556 issue_command(raw_cmd.cmdcode, raw_cmd.cmddata, raw_cmd.cmdlen);
559 static void mfm_recal_intr(void)
562 console_printf("recal intr - status = ");
565 outw(CMD_RCAL, MFM_COMMAND); /* Clear interrupt condition */
566 if (mfm_status & (STAT_DER | STAT_ABN)) {
567 printk("recal failed\n");
568 MFM_DRV_INFO.cylinder = NEED_2_RECAL;
575 /* Thats seek end - we are finished */
576 if (mfm_status & STAT_SED) {
577 issue_command(CMD_POD, NULL, 0);
578 MFM_DRV_INFO.cylinder = 0;
582 /* Command end without seek end (see data sheet p.20) for parallel seek
583 - we have to send a POL command to wait for the seek */
584 if (mfm_status & STAT_CED) {
585 do_mfm = mfm_recal_intr;
586 issue_command(CMD_POL, NULL, 0);
589 printk("recal: unknown status\n");
592 static void mfm_seek_intr(void)
595 console_printf("seek intr - status = ");
598 outw(CMD_RCAL, MFM_COMMAND); /* Clear interrupt condition */
599 if (mfm_status & (STAT_DER | STAT_ABN)) {
600 printk("seek failed\n");
601 MFM_DRV_INFO.cylinder = NEED_2_RECAL;
608 if (mfm_status & STAT_SED) {
609 issue_command(CMD_POD, NULL, 0);
610 MFM_DRV_INFO.cylinder = raw_cmd.cylinder;
614 if (mfm_status & STAT_CED) {
615 do_mfm = mfm_seek_intr;
616 issue_command(CMD_POL, NULL, 0);
619 printk("seek: unknown status\n");
622 /* IDEA2 seems to work better - its what RiscOS sets my
623 * disc to - on its SECOND call to specify!
628 #define SPEC_SH 0xa9 /* Step pulse high=21, Record Length=001 (256 bytes) */
630 #define SPEC_SL 0x00 /* OM2 - SL - step pulse low */
631 #define SPEC_SH 0x21 /* Step pulse high=4, Record Length=001 (256 bytes) */
634 static void mfm_setupspecify (int drive, unsigned char *cmdb)
636 cmdb[0] = 0x1f; /* OM0 - !SECT,!MOD,!DIF,PADP,ECD,CRCP,CRCI,ACOR */
637 cmdb[1] = 0xc3; /* OM1 - DTM,BRST,!CEDM,!SEDM,!DERM,0,AMEX,PSK */
638 cmdb[2] = SPEC_SL; /* OM2 - SL - step pulse low */
639 cmdb[3] = (number_mfm_drives == 1) ? 0x02 : 0x06; /* 1 or 2 drives */
640 cmdb[4] = 0xfc | ((mfm_info[drive].cylinders - 1) >> 8);/* RW time over/high part of number of cylinders */
641 cmdb[5] = mfm_info[drive].cylinders - 1; /* low part of number of cylinders */
642 cmdb[6] = mfm_info[drive].heads - 1; /* Number of heads */
643 cmdb[7] = mfm_info[drive].sectors - 1; /* Number of sectors */
645 cmdb[9] = 0x0a; /* gap length 1 */
646 cmdb[10] = 0x0d; /* gap length 2 */
647 cmdb[11] = 0x0c; /* gap length 3 */
648 cmdb[12] = (mfm_info[drive].precomp - 1) >> 8; /* pre comp cylinder */
649 cmdb[13] = mfm_info[drive].precomp - 1;
650 cmdb[14] = (mfm_info[drive].lowcurrent - 1) >> 8; /* Low current cylinder */
651 cmdb[15] = mfm_info[drive].lowcurrent - 1;
654 static void mfm_specify (void)
656 unsigned char cmdb[16];
658 DBG("specify...dev=%d lastspecified=%d\n", raw_cmd.dev, lastspecifieddrive);
659 mfm_setupspecify (raw_cmd.dev, cmdb);
661 issue_command (CMD_SPC, cmdb, 16);
662 /* Ensure that we will do another specify if we move to the other drive */
663 lastspecifieddrive = raw_cmd.dev;
664 wait_for_completion();
667 static void mfm_seek(void)
669 unsigned char cmdb[4];
672 if (MFM_DRV_INFO.cylinder < 0) {
673 do_mfm = mfm_recal_intr;
674 DBG("mfm_seek: about to call specify\n");
675 mfm_specify (); /* DAG added this */
677 cmdb[0] = raw_cmd.dev + 1;
680 issue_command(CMD_RCLB, cmdb, 2);
683 if (MFM_DRV_INFO.cylinder != raw_cmd.cylinder) {
684 cmdb[0] = raw_cmd.dev + 1;
685 cmdb[1] = 0; /* raw_cmd.head; DAG: My data sheet says this should be 0 */
686 cmdb[2] = raw_cmd.cylinder >> 8;
687 cmdb[3] = raw_cmd.cylinder;
689 do_mfm = mfm_seek_intr;
690 issue_command(CMD_SEK, cmdb, 4);
695 static void mfm_initialise(void)
701 static void request_done(int uptodate)
703 DBG("mfm:request_done\n");
705 unsigned char block[2] = {0, 0};
707 /* Apparently worked - let's check bytes left to DMA */
708 if (hdc63463_dataleft != (PartFragRead_SectorsLeft * 256)) {
709 printk("mfm: request_done - dataleft=%d - should be %d - Eek!\n", hdc63463_dataleft, PartFragRead_SectorsLeft * 256);
710 end_request(CURRENT, 0);
713 /* Potentially this means that we've done; but we might be doing
714 a partial access, (over two cylinders) or we may have a number
715 of fragments in an image file. First let's deal with partial accesss
718 /* Yep - a partial access */
720 /* and issue the remainder */
721 issue_request(PartFragRead_RestartBlock, PartFragRead_SectorsLeft, CURRENT);
725 /* ah well - perhaps there is another fragment to go */
727 /* Increment pointers/counts to start of next fragment */
728 if (SectorsLeftInRequest > 0) printk("mfm: SectorsLeftInRequest>0 - Eek! Shouldn't happen!\n");
730 /* No - its the end of the line */
731 /* end_request's should have happened at the end of sector DMAs */
732 /* Turns Drive LEDs off - may slow it down? */
733 if (!elv_next_request(QUEUE))
734 issue_command(CMD_CKV, block, 2);
737 DBG("request_done: About to mfm_request\n");
738 /* Next one please */
739 mfm_request(); /* Moved from mfm_rw_intr */
740 DBG("request_done: returned from mfm_request\n");
742 printk("mfm:request_done: update=0\n");
743 end_request(CURRENT, 0);
748 static void error_handler(void)
750 printk("error detected... status = ");
753 if (*errors > MFM_DRV_INFO.errors.abort)
755 if (*errors > MFM_DRV_INFO.errors.recal)
756 MFM_DRV_INFO.cylinder = NEED_2_RECAL;
759 static void rw_interrupt(void)
761 printk("rw_interrupt\n");
764 static struct cont rw_cont =
773 * Actually gets round to issuing the request - note everything at this
774 * point is in 256 byte sectors not Linux 512 byte blocks
776 static void issue_request(unsigned int block, unsigned int nsect,
779 struct gendisk *disk = req->rq_disk;
780 struct mfm_info *p = disk->private_data;
781 int track, start_head, start_sector;
782 int sectors_to_next_cyl;
785 track = block / p->sectors;
786 start_sector = block % p->sectors;
787 start_head = track % p->heads;
789 /* First get the number of whole tracks which are free before the next
791 sectors_to_next_cyl = (p->heads - (start_head + 1)) * p->sectors;
792 /* Then add in the number of sectors left on this track */
793 sectors_to_next_cyl += (p->sectors - start_sector);
795 DBG("issue_request: mfm_info[dev].sectors=%d track=%d\n", p->sectors, track);
798 raw_cmd.sector = start_sector;
799 raw_cmd.head = start_head;
800 raw_cmd.cylinder = track / p->heads;
801 raw_cmd.cmdtype = CURRENT->cmd;
802 raw_cmd.cmdcode = CURRENT->cmd == WRITE ? CMD_WD : CMD_RD;
803 raw_cmd.cmddata[0] = dev + 1; /* DAG: +1 to get US */
804 raw_cmd.cmddata[1] = raw_cmd.head;
805 raw_cmd.cmddata[2] = raw_cmd.cylinder >> 8;
806 raw_cmd.cmddata[3] = raw_cmd.cylinder;
807 raw_cmd.cmddata[4] = raw_cmd.head;
808 raw_cmd.cmddata[5] = raw_cmd.sector;
810 /* Was == and worked - how the heck??? */
811 if (lastspecifieddrive != raw_cmd.dev)
814 if (nsect <= sectors_to_next_cyl) {
815 raw_cmd.cmddata[6] = nsect >> 8;
816 raw_cmd.cmddata[7] = nsect;
817 PartFragRead = 0; /* All in one */
818 PartFragRead_SectorsLeft = 0; /* Must set this - used in DMA calcs */
820 raw_cmd.cmddata[6] = sectors_to_next_cyl >> 8;
821 raw_cmd.cmddata[7] = sectors_to_next_cyl;
822 PartFragRead = sectors_to_next_cyl; /* only do this many this time */
823 PartFragRead_RestartBlock = block + sectors_to_next_cyl; /* Where to restart from */
824 PartFragRead_SectorsLeft = nsect - sectors_to_next_cyl;
828 /* Setup DMA pointers */
829 hdc63463_dataptr = (unsigned int) Copy_buffer;
830 hdc63463_dataleft = nsect * 256; /* Better way? */
832 DBG("mfm%c: %sing: CHS=%d/%d/%d, sectors=%d, buffer=0x%08lx (%p)\n",
833 raw_cmd.dev + 'a', (CURRENT->cmd == READ) ? "read" : "writ",
836 raw_cmd.sector, nsect, (unsigned long) Copy_buffer, CURRENT);
839 errors = &(CURRENT->errors);
841 mfm_tq.routine = (void (*)(void *)) mfm_initialise;
842 queue_task(&mfm_tq, &tq_immediate);
843 mark_bh(IMMEDIATE_BH);
847 } /* issue_request */
850 * Called when an error has just happened - need to trick mfm_request
851 * into thinking we weren't busy
853 * Turn off ints - mfm_request expects them this way
855 static void mfm_rerequest(void)
857 DBG("mfm_rerequest\n");
863 static struct gendisk *mfm_gendisk[2];
865 static void mfm_request(void)
867 DBG("mfm_request CURRENT=%p Busy=%d\n", CURRENT, Busy);
869 /* If we are still processing then return; we will get called again */
871 /* Again seems to be common in 1.3.45 */
872 /*DBG*/printk("mfm_request: Exiting due to busy\n");
878 unsigned int block, nsect;
879 struct gendisk *disk;
881 DBG("mfm_request: loop start\n");
884 DBG("mfm_request: before !CURRENT\n");
887 printk("mfm_request: Exiting due to empty queue (pre)\n");
893 DBG("mfm_request: before arg extraction\n");
895 disk = CURRENT->rq_disk;
896 block = CURRENT->sector;
897 nsect = CURRENT->nr_sectors;
898 if (block >= get_capacity(disk) ||
899 block+nsect > get_capacity(disk)) {
900 printk("%s: bad access: block=%d, count=%d, nr_sects=%ld\n",
901 disk->disk_name, block, nsect, get_capacity(disk));
902 printk("mfm: continue 1\n");
903 end_request(CURRENT, 0);
908 /* DAG: Linux doesn't cope with this - even though it has an array telling
909 it the hardware block size - silly */
910 block <<= 1; /* Now in 256 byte sectors */
911 nsect <<= 1; /* Ditto */
913 SectorsLeftInRequest = nsect >> 1;
914 Sectors256LeftInCurrent = CURRENT->current_nr_sectors * 2;
915 Copy_buffer = CURRENT->buffer;
916 Copy_Sector = CURRENT->sector << 1;
918 DBG("mfm_request: block after offset=%d\n", block);
920 if (CURRENT->cmd != READ && CURRENT->cmd != WRITE) {
921 printk("unknown mfm-command %d\n", CURRENT->cmd);
922 end_request(CURRENT, 0);
924 printk("mfm: continue 4\n");
927 issue_request(block, nsect, CURRENT);
931 DBG("mfm_request: Dropping out bottom\n");
934 static void do_mfm_request(request_queue_t *q)
936 DBG("do_mfm_request: about to mfm_request\n");
940 static void mfm_interrupt_handler(int unused, void *dev_id)
942 void (*handler) (void) = do_mfm;
946 DBG("mfm_interrupt_handler (handler=0x%p)\n", handler);
948 mfm_status = inw(MFM_STATUS);
950 /* If CPR (Command Parameter Reject) and not busy it means that the command
951 has some return message to give us */
952 if ((mfm_status & (STAT_CPR | STAT_BSY)) == STAT_CPR) {
956 in = inw(MFM_DATAIN);
957 result[len++] = in >> 8;
965 outw (CMD_RCAL, MFM_COMMAND); /* Clear interrupt condition */
966 printk ("mfm: unexpected interrupt - status = ");
976 * Tell the user about the drive if we decided it exists.
978 static void mfm_geometry(int drive)
980 struct mfm_info *p = mfm_info + drive;
981 struct gendisk *disk = mfm_gendisk[drive];
982 disk->private_data = p;
984 printk ("%s: %dMB CHS=%d/%d/%d LCC=%d RECOMP=%d\n",
986 p->cylinders * p->heads * p->sectors / 4096,
987 p->cylinders, p->heads, p->sectors,
988 p->lowcurrent, p->precomp);
989 set_capacity(disk, p->cylinders * p->heads * p->sectors / 2);
992 #ifdef CONFIG_BLK_DEV_MFM_AUTODETECT
994 * Attempt to detect a drive and find its geometry. The drive has already been
997 * We first recalibrate the disk, then try to probe sectors, heads and then
998 * cylinders. NOTE! the cylinder probe may break drives. The xd disk driver
999 * does something along these lines, so I assume that most drives are up to
1000 * this mistreatment...
1002 static int mfm_detectdrive (int drive)
1004 unsigned int mingeo[3], maxgeo[3];
1005 unsigned int attribute, need_recal = 1;
1006 unsigned char cmdb[8];
1008 memset (mingeo, 0, sizeof (mingeo));
1009 maxgeo[0] = mfm_info[drive].sectors;
1010 maxgeo[1] = mfm_info[drive].heads;
1011 maxgeo[2] = mfm_info[drive].cylinders;
1013 cmdb[0] = drive + 1;
1016 for (attribute = 0; attribute < 3; attribute++) {
1017 while (mingeo[attribute] != maxgeo[attribute]) {
1018 unsigned int variable;
1020 variable = (maxgeo[attribute] + mingeo[attribute]) >> 1;
1021 cmdb[1] = cmdb[2] = cmdb[3] = cmdb[4] = cmdb[5] = 0;
1027 issue_command (CMD_RCLB, cmdb, 2);
1028 wait_for_completion ();
1029 wait_for_command_end ();
1030 if (result[1] == 0x20)
1032 } while (result[1] && --tries);
1034 outw (CMD_RCAL, MFM_COMMAND);
1040 switch (attribute) {
1043 issue_command (CMD_CMPD, cmdb, 8);
1048 issue_command (CMD_CMPD, cmdb, 8);
1051 cmdb[2] = variable >> 8;
1053 issue_command (CMD_SEK, cmdb, 4);
1056 wait_for_completion ();
1057 wait_for_command_end ();
1059 switch (result[1]) {
1062 mingeo[attribute] = variable + 1;
1066 outw (CMD_RCAL, MFM_COMMAND);
1072 maxgeo[attribute] = variable;
1077 mfm_info[drive].cylinders = mingeo[2];
1078 mfm_info[drive].lowcurrent = mingeo[2];
1079 mfm_info[drive].precomp = mingeo[2] / 2;
1080 mfm_info[drive].heads = mingeo[1];
1081 mfm_info[drive].sectors = mingeo[0];
1082 outw (CMD_RCAL, MFM_COMMAND);
1088 * Initialise all drive information for this controller.
1090 static int mfm_initdrives(void)
1094 if (number_mfm_drives > MFM_MAXDRIVES) {
1095 number_mfm_drives = MFM_MAXDRIVES;
1096 printk("No. of ADFS MFM drives is greater than MFM_MAXDRIVES - you can't have that many!\n");
1099 for (drive = 0; drive < number_mfm_drives; drive++) {
1100 mfm_info[drive].lowcurrent = 1;
1101 mfm_info[drive].precomp = 1;
1102 mfm_info[drive].cylinder = -1;
1103 mfm_info[drive].errors.recal = 0;
1104 mfm_info[drive].errors.report = 0;
1105 mfm_info[drive].errors.abort = 4;
1107 #ifdef CONFIG_BLK_DEV_MFM_AUTODETECT
1108 mfm_info[drive].cylinders = 1024;
1109 mfm_info[drive].heads = 8;
1110 mfm_info[drive].sectors = 64;
1112 unsigned char cmdb[16];
1114 mfm_setupspecify (drive, cmdb);
1116 issue_command (CMD_SPC, cmdb, 16);
1117 wait_for_completion ();
1118 if (!mfm_detectdrive (drive)) {
1119 mfm_info[drive].cylinders = 0;
1120 mfm_info[drive].heads = 0;
1121 mfm_info[drive].sectors = 0;
1123 cmdb[0] = cmdb[1] = 0;
1124 issue_command (CMD_CKV, cmdb, 2);
1127 mfm_info[drive].cylinders = 1; /* its going to have to figure it out from the partition info */
1128 mfm_info[drive].heads = 4;
1129 mfm_info[drive].sectors = 32;
1132 return number_mfm_drives;
1138 * The 'front' end of the mfm driver follows...
1141 static int mfm_getgeo(struct block_device *bdev, struct hd_geometry *geo)
1143 struct mfm_info *p = bdev->bd_disk->private_data;
1145 geo->heads = p->heads;
1146 geo->sectors = p->sectors;
1147 geo->cylinders = p->cylinders;
1152 * This is to handle various kernel command line parameters
1153 * specific to this driver.
1155 void mfm_setup(char *str, int *ints)
1161 * Set the CHS from the ADFS boot block if it is present. This is not ideal
1162 * since if there are any non-ADFS partitions on the disk, this won't work!
1163 * Hence, I want to get rid of this...
1165 void xd_set_geometry(struct block_device *bdev, unsigned char secsptrack,
1166 unsigned char heads, unsigned int secsize)
1168 struct mfm_info *p = bdev->bd_disk->private_data;
1169 int drive = p - mfm_info;
1170 unsigned long disksize = bdev->bd_inode->i_size;
1172 if (p->cylinders == 1) {
1173 p->sectors = secsptrack;
1175 p->cylinders = discsize / (secsptrack * heads * secsize);
1177 if ((heads < 1) || (p->cylinders > 1024)) {
1178 printk("%s: Insane disc shape! Setting to 512/4/32\n",
1179 bdev->bd_disk->disk_name);
1181 /* These values are fairly arbitary, but are there so that if your
1182 * lucky you can pick apart your disc to find out what is going on -
1183 * I reckon these figures won't hurt MOST drives
1189 if (raw_cmd.dev == drive)
1191 mfm_geometry (drive);
1195 static struct block_device_operations mfm_fops =
1197 .owner = THIS_MODULE,
1198 .getgeo = mfm_getgeo,
1202 * See if there is a controller at the address presently at mfm_addr
1204 * We check to see if the controller is busy - if it is, we abort it first,
1205 * and check that the chip is no longer busy after at least 180 clock cycles.
1206 * We then issue a command and check that the BSY or CPR bits are set.
1208 static int mfm_probecontroller (unsigned int mfm_addr)
1210 if (inw (MFM_STATUS) & STAT_BSY) {
1211 outw (CMD_ABT, MFM_COMMAND);
1213 if (inw (MFM_STATUS) & STAT_BSY)
1217 if (inw (MFM_STATUS) & STAT_CED)
1218 outw (CMD_RCAL, MFM_COMMAND);
1220 outw (CMD_SEK, MFM_COMMAND);
1222 if (inw (MFM_STATUS) & (STAT_BSY | STAT_CPR)) {
1223 unsigned int count = 2000;
1224 while (inw (MFM_STATUS) & STAT_BSY) {
1230 outw (CMD_RCAL, MFM_COMMAND);
1235 static int mfm_do_init(unsigned char irqmask)
1239 printk("mfm: found at address %08X, interrupt %d\n", mfm_addr, mfm_irq);
1242 if (!request_region (mfm_addr, 10, "mfm"))
1245 ret = register_blkdev(MAJOR_NR, "mfm");
1249 /* Stuff for the assembler routines to get to */
1250 hdc63463_baseaddress = ioaddr(mfm_addr);
1251 hdc63463_irqpolladdress = mfm_IRQPollLoc;
1252 hdc63463_irqpollmask = irqmask;
1254 mfm_queue = blk_init_queue(do_mfm_request, &mfm_lock);
1259 lastspecifieddrive = -1;
1261 mfm_drives = mfm_initdrives();
1267 for (i = 0; i < mfm_drives; i++) {
1268 struct gendisk *disk = alloc_disk(64);
1271 disk->major = MAJOR_NR;
1272 disk->first_minor = i << 6;
1273 disk->fops = &mfm_fops;
1274 sprintf(disk->disk_name, "mfm%c", 'a'+i);
1275 mfm_gendisk[i] = disk;
1278 printk("mfm: detected %d hard drive%s\n", mfm_drives,
1279 mfm_drives == 1 ? "" : "s");
1280 ret = request_irq(mfm_irq, mfm_interrupt_handler, IRQF_DISABLED, "MFM harddisk", NULL);
1282 printk("mfm: unable to get IRQ%d\n", mfm_irq);
1287 outw(0x80, mfm_irqenable); /* Required to enable IRQs from MFM podule */
1289 for (i = 0; i < mfm_drives; i++) {
1291 mfm_gendisk[i]->queue = mfm_queue;
1292 add_disk(mfm_gendisk[i]);
1297 for (i = 0; i < mfm_drives; i++)
1298 put_disk(mfm_gendisk[i]);
1300 blk_cleanup_queue(mfm_queue);
1302 unregister_blkdev(MAJOR_NR, "mfm");
1304 release_region(mfm_addr, 10);
1309 put_disk(mfm_gendisk[i]);
1313 static void mfm_do_exit(void)
1317 free_irq(mfm_irq, NULL);
1318 for (i = 0; i < mfm_drives; i++) {
1319 del_gendisk(mfm_gendisk[i]);
1320 put_disk(mfm_gendisk[i]);
1322 blk_cleanup_queue(mfm_queue);
1323 unregister_blkdev(MAJOR_NR, "mfm");
1325 release_region(mfm_addr, 10);
1328 static int __devinit mfm_probe(struct expansion_card *ec, struct ecard_id *id)
1333 mfm_addr = ecard_address(ec, ECARD_IOC, ECARD_MEDIUM) + 0x800;
1334 mfm_IRQPollLoc = ioaddr(mfm_addr + 0x400);
1335 mfm_irqenable = mfm_IRQPollLoc;
1338 return mfm_do_init(0x08);
1341 static void __devexit mfm_remove(struct expansion_card *ec)
1343 outw (0, mfm_irqenable); /* Required to enable IRQs from MFM podule */
1347 static const struct ecard_id mfm_cids[] = {
1348 { MANU_ACORN, PROD_ACORN_MFM },
1352 static struct ecard_driver mfm_driver = {
1354 .remove = __devexit(mfm_remove),
1355 .id_table = mfm_cids,
1362 * Look for a MFM controller - first check the motherboard, then the podules
1363 * The podules have an extra interrupt enable that needs to be played with
1365 * The HDC is accessed at MEDIUM IOC speeds.
1367 static int __init mfm_init (void)
1369 unsigned char irqmask;
1371 if (mfm_probecontroller(ONBOARD_MFM_ADDRESS)) {
1372 mfm_addr = ONBOARD_MFM_ADDRESS;
1373 mfm_IRQPollLoc = IOC_IRQSTATB;
1375 mfm_irq = IRQ_HARDDISK;
1376 return mfm_do_init(0x08); /* IL3 pin */
1378 return ecard_register_driver(&mfm_driver);
1382 static void __exit mfm_exit(void)
1384 if (mfm_addr == ONBOARD_MFM_ADDRESS)
1387 ecard_unregister_driver(&mfm_driver);
1390 module_init(mfm_init)
1391 module_exit(mfm_exit)
1392 MODULE_LICENSE("GPL");