blob: 242029c9c0ca9a5e9e61b64011a3cd9dce7c31fd [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Copyright (C) 1991, 1992 Linus Torvalds
3 *
4 * This is the low-level hd interrupt support. It traverses the
5 * request-list, using interrupts to jump between functions. As
6 * all the functions are called within interrupts, we may not
7 * sleep. Special care is recommended.
8 *
9 * modified by Drew Eckhardt to check nr of hd's from the CMOS.
10 *
11 * Thanks to Branko Lankester, lankeste@fwi.uva.nl, who found a bug
12 * in the early extended-partition checks and added DM partitions
13 *
14 * IRQ-unmask, drive-id, multiple-mode, support for ">16 heads",
15 * and general streamlining by Mark Lord.
16 *
17 * Removed 99% of above. Use Mark's ide driver for those options.
18 * This is now a lightweight ST-506 driver. (Paul Gortmaker)
19 *
20 * Modified 1995 Russell King for ARM processor.
21 *
22 * Bugfix: max_sectors must be <= 255 or the wheels tend to come
23 * off in a hurry once you queue things up - Paul G. 02/2001
24 */
25
26/* Uncomment the following if you want verbose error reports. */
27/* #define VERBOSE_ERRORS */
28
29#include <linux/blkdev.h>
30#include <linux/errno.h>
31#include <linux/signal.h>
32#include <linux/interrupt.h>
33#include <linux/timer.h>
34#include <linux/fs.h>
35#include <linux/kernel.h>
36#include <linux/genhd.h>
37#include <linux/slab.h>
38#include <linux/string.h>
39#include <linux/ioport.h>
40#include <linux/mc146818rtc.h> /* CMOS defines */
41#include <linux/init.h>
42#include <linux/blkpg.h>
43#include <linux/hdreg.h>
44
45#define REALLY_SLOW_IO
46#include <asm/system.h>
47#include <asm/io.h>
48#include <asm/uaccess.h>
49
50#ifdef __arm__
51#undef HD_IRQ
52#endif
53#include <asm/irq.h>
54#ifdef __arm__
55#define HD_IRQ IRQ_HARDDISK
56#endif
57
58/* Hd controller regster ports */
59
60#define HD_DATA 0x1f0 /* _CTL when writing */
61#define HD_ERROR 0x1f1 /* see err-bits */
62#define HD_NSECTOR 0x1f2 /* nr of sectors to read/write */
63#define HD_SECTOR 0x1f3 /* starting sector */
64#define HD_LCYL 0x1f4 /* starting cylinder */
65#define HD_HCYL 0x1f5 /* high byte of starting cyl */
66#define HD_CURRENT 0x1f6 /* 101dhhhh , d=drive, hhhh=head */
67#define HD_STATUS 0x1f7 /* see status-bits */
68#define HD_FEATURE HD_ERROR /* same io address, read=error, write=feature */
69#define HD_PRECOMP HD_FEATURE /* obsolete use of this port - predates IDE */
70#define HD_COMMAND HD_STATUS /* same io address, read=status, write=cmd */
71
72#define HD_CMD 0x3f6 /* used for resets */
73#define HD_ALTSTATUS 0x3f6 /* same as HD_STATUS but doesn't clear irq */
74
75/* Bits of HD_STATUS */
76#define ERR_STAT 0x01
77#define INDEX_STAT 0x02
78#define ECC_STAT 0x04 /* Corrected error */
79#define DRQ_STAT 0x08
80#define SEEK_STAT 0x10
81#define SERVICE_STAT SEEK_STAT
82#define WRERR_STAT 0x20
83#define READY_STAT 0x40
84#define BUSY_STAT 0x80
85
86/* Bits for HD_ERROR */
87#define MARK_ERR 0x01 /* Bad address mark */
88#define TRK0_ERR 0x02 /* couldn't find track 0 */
89#define ABRT_ERR 0x04 /* Command aborted */
90#define MCR_ERR 0x08 /* media change request */
91#define ID_ERR 0x10 /* ID field not found */
92#define MC_ERR 0x20 /* media changed */
93#define ECC_ERR 0x40 /* Uncorrectable ECC error */
94#define BBD_ERR 0x80 /* pre-EIDE meaning: block marked bad */
95#define ICRC_ERR 0x80 /* new meaning: CRC error during transfer */
96
97static DEFINE_SPINLOCK(hd_lock);
98static struct request_queue *hd_queue;
99
100#define MAJOR_NR HD_MAJOR
101#define QUEUE (hd_queue)
102#define CURRENT elv_next_request(hd_queue)
103
104#define TIMEOUT_VALUE (6*HZ)
105#define HD_DELAY 0
106
107#define MAX_ERRORS 16 /* Max read/write errors/sector */
108#define RESET_FREQ 8 /* Reset controller every 8th retry */
109#define RECAL_FREQ 4 /* Recalibrate every 4th retry */
110#define MAX_HD 2
111
112#define STAT_OK (READY_STAT|SEEK_STAT)
113#define OK_STATUS(s) (((s)&(STAT_OK|(BUSY_STAT|WRERR_STAT|ERR_STAT)))==STAT_OK)
114
115static void recal_intr(void);
116static void bad_rw_intr(void);
117
118static int reset;
119static int hd_error;
120
121/*
122 * This struct defines the HD's and their types.
123 */
124struct hd_i_struct {
125 unsigned int head,sect,cyl,wpcom,lzone,ctl;
126 int unit;
127 int recalibrate;
128 int special_op;
129};
130
131#ifdef HD_TYPE
132static struct hd_i_struct hd_info[] = { HD_TYPE };
133static int NR_HD = ((sizeof (hd_info))/(sizeof (struct hd_i_struct)));
134#else
135static struct hd_i_struct hd_info[MAX_HD];
136static int NR_HD;
137#endif
138
139static struct gendisk *hd_gendisk[MAX_HD];
140
141static struct timer_list device_timer;
142
143#define TIMEOUT_VALUE (6*HZ)
144
145#define SET_TIMER \
146 do { \
147 mod_timer(&device_timer, jiffies + TIMEOUT_VALUE); \
148 } while (0)
149
150static void (*do_hd)(void) = NULL;
151#define SET_HANDLER(x) \
152if ((do_hd = (x)) != NULL) \
153 SET_TIMER; \
154else \
155 del_timer(&device_timer);
156
157
158#if (HD_DELAY > 0)
Ingo Molnar306e4402005-06-30 02:58:55 -0700159
160#include <asm/i8253.h>
161
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162unsigned long last_req;
163
164unsigned long read_timer(void)
165{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166 unsigned long t, flags;
167 int i;
168
169 spin_lock_irqsave(&i8253_lock, flags);
170 t = jiffies * 11932;
171 outb_p(0, 0x43);
172 i = inb_p(0x40);
173 i |= inb(0x40) << 8;
174 spin_unlock_irqrestore(&i8253_lock, flags);
175 return(t - i);
176}
177#endif
178
179static void __init hd_setup(char *str, int *ints)
180{
181 int hdind = 0;
182
183 if (ints[0] != 3)
184 return;
185 if (hd_info[0].head != 0)
186 hdind=1;
187 hd_info[hdind].head = ints[2];
188 hd_info[hdind].sect = ints[3];
189 hd_info[hdind].cyl = ints[1];
190 hd_info[hdind].wpcom = 0;
191 hd_info[hdind].lzone = ints[1];
192 hd_info[hdind].ctl = (ints[2] > 8 ? 8 : 0);
193 NR_HD = hdind+1;
194}
195
196static void dump_status (const char *msg, unsigned int stat)
197{
198 char *name = "hd?";
199 if (CURRENT)
200 name = CURRENT->rq_disk->disk_name;
201
202#ifdef VERBOSE_ERRORS
203 printk("%s: %s: status=0x%02x { ", name, msg, stat & 0xff);
204 if (stat & BUSY_STAT) printk("Busy ");
205 if (stat & READY_STAT) printk("DriveReady ");
206 if (stat & WRERR_STAT) printk("WriteFault ");
207 if (stat & SEEK_STAT) printk("SeekComplete ");
208 if (stat & DRQ_STAT) printk("DataRequest ");
209 if (stat & ECC_STAT) printk("CorrectedError ");
210 if (stat & INDEX_STAT) printk("Index ");
211 if (stat & ERR_STAT) printk("Error ");
212 printk("}\n");
213 if ((stat & ERR_STAT) == 0) {
214 hd_error = 0;
215 } else {
216 hd_error = inb(HD_ERROR);
217 printk("%s: %s: error=0x%02x { ", name, msg, hd_error & 0xff);
218 if (hd_error & BBD_ERR) printk("BadSector ");
219 if (hd_error & ECC_ERR) printk("UncorrectableError ");
220 if (hd_error & ID_ERR) printk("SectorIdNotFound ");
221 if (hd_error & ABRT_ERR) printk("DriveStatusError ");
222 if (hd_error & TRK0_ERR) printk("TrackZeroNotFound ");
223 if (hd_error & MARK_ERR) printk("AddrMarkNotFound ");
224 printk("}");
225 if (hd_error & (BBD_ERR|ECC_ERR|ID_ERR|MARK_ERR)) {
226 printk(", CHS=%d/%d/%d", (inb(HD_HCYL)<<8) + inb(HD_LCYL),
227 inb(HD_CURRENT) & 0xf, inb(HD_SECTOR));
228 if (CURRENT)
229 printk(", sector=%ld", CURRENT->sector);
230 }
231 printk("\n");
232 }
233#else
234 printk("%s: %s: status=0x%02x.\n", name, msg, stat & 0xff);
235 if ((stat & ERR_STAT) == 0) {
236 hd_error = 0;
237 } else {
238 hd_error = inb(HD_ERROR);
239 printk("%s: %s: error=0x%02x.\n", name, msg, hd_error & 0xff);
240 }
241#endif
242}
243
244static void check_status(void)
245{
246 int i = inb_p(HD_STATUS);
247
248 if (!OK_STATUS(i)) {
249 dump_status("check_status", i);
250 bad_rw_intr();
251 }
252}
253
254static int controller_busy(void)
255{
256 int retries = 100000;
257 unsigned char status;
258
259 do {
260 status = inb_p(HD_STATUS);
261 } while ((status & BUSY_STAT) && --retries);
262 return status;
263}
264
265static int status_ok(void)
266{
267 unsigned char status = inb_p(HD_STATUS);
268
269 if (status & BUSY_STAT)
270 return 1; /* Ancient, but does it make sense??? */
271 if (status & WRERR_STAT)
272 return 0;
273 if (!(status & READY_STAT))
274 return 0;
275 if (!(status & SEEK_STAT))
276 return 0;
277 return 1;
278}
279
280static int controller_ready(unsigned int drive, unsigned int head)
281{
282 int retry = 100;
283
284 do {
285 if (controller_busy() & BUSY_STAT)
286 return 0;
287 outb_p(0xA0 | (drive<<4) | head, HD_CURRENT);
288 if (status_ok())
289 return 1;
290 } while (--retry);
291 return 0;
292}
293
294
295static void hd_out(struct hd_i_struct *disk,
296 unsigned int nsect,
297 unsigned int sect,
298 unsigned int head,
299 unsigned int cyl,
300 unsigned int cmd,
301 void (*intr_addr)(void))
302{
303 unsigned short port;
304
305#if (HD_DELAY > 0)
306 while (read_timer() - last_req < HD_DELAY)
307 /* nothing */;
308#endif
309 if (reset)
310 return;
311 if (!controller_ready(disk->unit, head)) {
312 reset = 1;
313 return;
314 }
315 SET_HANDLER(intr_addr);
316 outb_p(disk->ctl,HD_CMD);
317 port=HD_DATA;
318 outb_p(disk->wpcom>>2,++port);
319 outb_p(nsect,++port);
320 outb_p(sect,++port);
321 outb_p(cyl,++port);
322 outb_p(cyl>>8,++port);
323 outb_p(0xA0|(disk->unit<<4)|head,++port);
324 outb_p(cmd,++port);
325}
326
327static void hd_request (void);
328
329static int drive_busy(void)
330{
331 unsigned int i;
332 unsigned char c;
333
334 for (i = 0; i < 500000 ; i++) {
335 c = inb_p(HD_STATUS);
336 if ((c & (BUSY_STAT | READY_STAT | SEEK_STAT)) == STAT_OK)
337 return 0;
338 }
339 dump_status("reset timed out", c);
340 return 1;
341}
342
343static void reset_controller(void)
344{
345 int i;
346
347 outb_p(4,HD_CMD);
348 for(i = 0; i < 1000; i++) barrier();
349 outb_p(hd_info[0].ctl & 0x0f,HD_CMD);
350 for(i = 0; i < 1000; i++) barrier();
351 if (drive_busy())
352 printk("hd: controller still busy\n");
353 else if ((hd_error = inb(HD_ERROR)) != 1)
354 printk("hd: controller reset failed: %02x\n",hd_error);
355}
356
357static void reset_hd(void)
358{
359 static int i;
360
361repeat:
362 if (reset) {
363 reset = 0;
364 i = -1;
365 reset_controller();
366 } else {
367 check_status();
368 if (reset)
369 goto repeat;
370 }
371 if (++i < NR_HD) {
372 struct hd_i_struct *disk = &hd_info[i];
373 disk->special_op = disk->recalibrate = 1;
374 hd_out(disk,disk->sect,disk->sect,disk->head-1,
375 disk->cyl,WIN_SPECIFY,&reset_hd);
376 if (reset)
377 goto repeat;
378 } else
379 hd_request();
380}
381
382/*
383 * Ok, don't know what to do with the unexpected interrupts: on some machines
384 * doing a reset and a retry seems to result in an eternal loop. Right now I
385 * ignore it, and just set the timeout.
386 *
387 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever the
388 * drive enters "idle", "standby", or "sleep" mode, so if the status looks
389 * "good", we just ignore the interrupt completely.
390 */
391static void unexpected_hd_interrupt(void)
392{
393 unsigned int stat = inb_p(HD_STATUS);
394
395 if (stat & (BUSY_STAT|DRQ_STAT|ECC_STAT|ERR_STAT)) {
396 dump_status ("unexpected interrupt", stat);
397 SET_TIMER;
398 }
399}
400
401/*
402 * bad_rw_intr() now tries to be a bit smarter and does things
403 * according to the error returned by the controller.
404 * -Mika Liljeberg (liljeber@cs.Helsinki.FI)
405 */
406static void bad_rw_intr(void)
407{
408 struct request *req = CURRENT;
409 if (req != NULL) {
410 struct hd_i_struct *disk = req->rq_disk->private_data;
411 if (++req->errors >= MAX_ERRORS || (hd_error & BBD_ERR)) {
412 end_request(req, 0);
413 disk->special_op = disk->recalibrate = 1;
414 } else if (req->errors % RESET_FREQ == 0)
415 reset = 1;
416 else if ((hd_error & TRK0_ERR) || req->errors % RECAL_FREQ == 0)
417 disk->special_op = disk->recalibrate = 1;
418 /* Otherwise just retry */
419 }
420}
421
422static inline int wait_DRQ(void)
423{
424 int retries = 100000, stat;
425
426 while (--retries > 0)
427 if ((stat = inb_p(HD_STATUS)) & DRQ_STAT)
428 return 0;
429 dump_status("wait_DRQ", stat);
430 return -1;
431}
432
433static void read_intr(void)
434{
435 struct request *req;
436 int i, retries = 100000;
437
438 do {
439 i = (unsigned) inb_p(HD_STATUS);
440 if (i & BUSY_STAT)
441 continue;
442 if (!OK_STATUS(i))
443 break;
444 if (i & DRQ_STAT)
445 goto ok_to_read;
446 } while (--retries > 0);
447 dump_status("read_intr", i);
448 bad_rw_intr();
449 hd_request();
450 return;
451ok_to_read:
452 req = CURRENT;
453 insw(HD_DATA,req->buffer,256);
454 req->sector++;
455 req->buffer += 512;
456 req->errors = 0;
457 i = --req->nr_sectors;
458 --req->current_nr_sectors;
459#ifdef DEBUG
460 printk("%s: read: sector %ld, remaining = %ld, buffer=%p\n",
461 req->rq_disk->disk_name, req->sector, req->nr_sectors,
462 req->buffer+512));
463#endif
464 if (req->current_nr_sectors <= 0)
465 end_request(req, 1);
466 if (i > 0) {
467 SET_HANDLER(&read_intr);
468 return;
469 }
470 (void) inb_p(HD_STATUS);
471#if (HD_DELAY > 0)
472 last_req = read_timer();
473#endif
474 if (elv_next_request(QUEUE))
475 hd_request();
476 return;
477}
478
479static void write_intr(void)
480{
481 struct request *req = CURRENT;
482 int i;
483 int retries = 100000;
484
485 do {
486 i = (unsigned) inb_p(HD_STATUS);
487 if (i & BUSY_STAT)
488 continue;
489 if (!OK_STATUS(i))
490 break;
491 if ((req->nr_sectors <= 1) || (i & DRQ_STAT))
492 goto ok_to_write;
493 } while (--retries > 0);
494 dump_status("write_intr", i);
495 bad_rw_intr();
496 hd_request();
497 return;
498ok_to_write:
499 req->sector++;
500 i = --req->nr_sectors;
501 --req->current_nr_sectors;
502 req->buffer += 512;
503 if (!i || (req->bio && req->current_nr_sectors <= 0))
504 end_request(req, 1);
505 if (i > 0) {
506 SET_HANDLER(&write_intr);
507 outsw(HD_DATA,req->buffer,256);
508 local_irq_enable();
509 } else {
510#if (HD_DELAY > 0)
511 last_req = read_timer();
512#endif
513 hd_request();
514 }
515 return;
516}
517
518static void recal_intr(void)
519{
520 check_status();
521#if (HD_DELAY > 0)
522 last_req = read_timer();
523#endif
524 hd_request();
525}
526
527/*
528 * This is another of the error-routines I don't know what to do with. The
529 * best idea seems to just set reset, and start all over again.
530 */
531static void hd_times_out(unsigned long dummy)
532{
533 char *name;
534
535 do_hd = NULL;
536
537 if (!CURRENT)
538 return;
539
540 disable_irq(HD_IRQ);
541 local_irq_enable();
542 reset = 1;
543 name = CURRENT->rq_disk->disk_name;
544 printk("%s: timeout\n", name);
545 if (++CURRENT->errors >= MAX_ERRORS) {
546#ifdef DEBUG
547 printk("%s: too many errors\n", name);
548#endif
549 end_request(CURRENT, 0);
550 }
551 local_irq_disable();
552 hd_request();
553 enable_irq(HD_IRQ);
554}
555
556static int do_special_op(struct hd_i_struct *disk, struct request *req)
557{
558 if (disk->recalibrate) {
559 disk->recalibrate = 0;
560 hd_out(disk,disk->sect,0,0,0,WIN_RESTORE,&recal_intr);
561 return reset;
562 }
563 if (disk->head > 16) {
564 printk ("%s: cannot handle device with more than 16 heads - giving up\n", req->rq_disk->disk_name);
565 end_request(req, 0);
566 }
567 disk->special_op = 0;
568 return 1;
569}
570
571/*
572 * The driver enables interrupts as much as possible. In order to do this,
573 * (a) the device-interrupt is disabled before entering hd_request(),
574 * and (b) the timeout-interrupt is disabled before the sti().
575 *
576 * Interrupts are still masked (by default) whenever we are exchanging
577 * data/cmds with a drive, because some drives seem to have very poor
578 * tolerance for latency during I/O. The IDE driver has support to unmask
579 * interrupts for non-broken hardware, so use that driver if required.
580 */
581static void hd_request(void)
582{
583 unsigned int block, nsect, sec, track, head, cyl;
584 struct hd_i_struct *disk;
585 struct request *req;
586
587 if (do_hd)
588 return;
589repeat:
590 del_timer(&device_timer);
591 local_irq_enable();
592
593 req = CURRENT;
594 if (!req) {
595 do_hd = NULL;
596 return;
597 }
598
599 if (reset) {
600 local_irq_disable();
601 reset_hd();
602 return;
603 }
604 disk = req->rq_disk->private_data;
605 block = req->sector;
606 nsect = req->nr_sectors;
607 if (block >= get_capacity(req->rq_disk) ||
608 ((block+nsect) > get_capacity(req->rq_disk))) {
609 printk("%s: bad access: block=%d, count=%d\n",
610 req->rq_disk->disk_name, block, nsect);
611 end_request(req, 0);
612 goto repeat;
613 }
614
615 if (disk->special_op) {
616 if (do_special_op(disk, req))
617 goto repeat;
618 return;
619 }
620 sec = block % disk->sect + 1;
621 track = block / disk->sect;
622 head = track % disk->head;
623 cyl = track / disk->head;
624#ifdef DEBUG
625 printk("%s: %sing: CHS=%d/%d/%d, sectors=%d, buffer=%p\n",
626 req->rq_disk->disk_name, (req->cmd == READ)?"read":"writ",
627 cyl, head, sec, nsect, req->buffer);
628#endif
629 if (req->flags & REQ_CMD) {
630 switch (rq_data_dir(req)) {
631 case READ:
632 hd_out(disk,nsect,sec,head,cyl,WIN_READ,&read_intr);
633 if (reset)
634 goto repeat;
635 break;
636 case WRITE:
637 hd_out(disk,nsect,sec,head,cyl,WIN_WRITE,&write_intr);
638 if (reset)
639 goto repeat;
640 if (wait_DRQ()) {
641 bad_rw_intr();
642 goto repeat;
643 }
644 outsw(HD_DATA,req->buffer,256);
645 break;
646 default:
647 printk("unknown hd-command\n");
648 end_request(req, 0);
649 break;
650 }
651 }
652}
653
654static void do_hd_request (request_queue_t * q)
655{
656 disable_irq(HD_IRQ);
657 hd_request();
658 enable_irq(HD_IRQ);
659}
660
661static int hd_ioctl(struct inode * inode, struct file * file,
662 unsigned int cmd, unsigned long arg)
663{
664 struct hd_i_struct *disk = inode->i_bdev->bd_disk->private_data;
665 struct hd_geometry __user *loc = (struct hd_geometry __user *) arg;
666 struct hd_geometry g;
667
668 if (cmd != HDIO_GETGEO)
669 return -EINVAL;
670 if (!loc)
671 return -EINVAL;
672 g.heads = disk->head;
673 g.sectors = disk->sect;
674 g.cylinders = disk->cyl;
675 g.start = get_start_sect(inode->i_bdev);
676 return copy_to_user(loc, &g, sizeof g) ? -EFAULT : 0;
677}
678
679/*
680 * Releasing a block device means we sync() it, so that it can safely
681 * be forgotten about...
682 */
683
684static irqreturn_t hd_interrupt(int irq, void *dev_id, struct pt_regs *regs)
685{
686 void (*handler)(void) = do_hd;
687
688 do_hd = NULL;
689 del_timer(&device_timer);
690 if (!handler)
691 handler = unexpected_hd_interrupt;
692 handler();
693 local_irq_enable();
694 return IRQ_HANDLED;
695}
696
697static struct block_device_operations hd_fops = {
698 .ioctl = hd_ioctl,
699};
700
701/*
702 * This is the hard disk IRQ description. The SA_INTERRUPT in sa_flags
703 * means we run the IRQ-handler with interrupts disabled: this is bad for
704 * interrupt latency, but anything else has led to problems on some
705 * machines.
706 *
707 * We enable interrupts in some of the routines after making sure it's
708 * safe.
709 */
710
711static int __init hd_init(void)
712{
713 int drive;
714
715 if (register_blkdev(MAJOR_NR,"hd"))
716 return -1;
717
718 hd_queue = blk_init_queue(do_hd_request, &hd_lock);
719 if (!hd_queue) {
720 unregister_blkdev(MAJOR_NR,"hd");
721 return -ENOMEM;
722 }
723
724 blk_queue_max_sectors(hd_queue, 255);
725 init_timer(&device_timer);
726 device_timer.function = hd_times_out;
727 blk_queue_hardsect_size(hd_queue, 512);
728
729#ifdef __i386__
730 if (!NR_HD) {
731 extern struct drive_info drive_info;
732 unsigned char *BIOS = (unsigned char *) &drive_info;
733 unsigned long flags;
734 int cmos_disks;
735
736 for (drive=0 ; drive<2 ; drive++) {
737 hd_info[drive].cyl = *(unsigned short *) BIOS;
738 hd_info[drive].head = *(2+BIOS);
739 hd_info[drive].wpcom = *(unsigned short *) (5+BIOS);
740 hd_info[drive].ctl = *(8+BIOS);
741 hd_info[drive].lzone = *(unsigned short *) (12+BIOS);
742 hd_info[drive].sect = *(14+BIOS);
743#ifdef does_not_work_for_everybody_with_scsi_but_helps_ibm_vp
744 if (hd_info[drive].cyl && NR_HD == drive)
745 NR_HD++;
746#endif
747 BIOS += 16;
748 }
749
750 /*
751 We query CMOS about hard disks : it could be that
752 we have a SCSI/ESDI/etc controller that is BIOS
753 compatible with ST-506, and thus showing up in our
754 BIOS table, but not register compatible, and therefore
755 not present in CMOS.
756
757 Furthermore, we will assume that our ST-506 drives
758 <if any> are the primary drives in the system, and
759 the ones reflected as drive 1 or 2.
760
761 The first drive is stored in the high nibble of CMOS
762 byte 0x12, the second in the low nibble. This will be
763 either a 4 bit drive type or 0xf indicating use byte 0x19
764 for an 8 bit type, drive 1, 0x1a for drive 2 in CMOS.
765
766 Needless to say, a non-zero value means we have
767 an AT controller hard disk for that drive.
768
769 Currently the rtc_lock is a bit academic since this
770 driver is non-modular, but someday... ? Paul G.
771 */
772
773 spin_lock_irqsave(&rtc_lock, flags);
774 cmos_disks = CMOS_READ(0x12);
775 spin_unlock_irqrestore(&rtc_lock, flags);
776
777 if (cmos_disks & 0xf0) {
778 if (cmos_disks & 0x0f)
779 NR_HD = 2;
780 else
781 NR_HD = 1;
782 }
783 }
784#endif /* __i386__ */
785#ifdef __arm__
786 if (!NR_HD) {
787 /* We don't know anything about the drive. This means
788 * that you *MUST* specify the drive parameters to the
789 * kernel yourself.
790 */
791 printk("hd: no drives specified - use hd=cyl,head,sectors"
792 " on kernel command line\n");
793 }
794#endif
795 if (!NR_HD)
796 goto out;
797
798 for (drive=0 ; drive < NR_HD ; drive++) {
799 struct gendisk *disk = alloc_disk(64);
800 struct hd_i_struct *p = &hd_info[drive];
801 if (!disk)
802 goto Enomem;
803 disk->major = MAJOR_NR;
804 disk->first_minor = drive << 6;
805 disk->fops = &hd_fops;
806 sprintf(disk->disk_name, "hd%c", 'a'+drive);
807 disk->private_data = p;
808 set_capacity(disk, p->head * p->sect * p->cyl);
809 disk->queue = hd_queue;
810 p->unit = drive;
811 hd_gendisk[drive] = disk;
812 printk ("%s: %luMB, CHS=%d/%d/%d\n",
813 disk->disk_name, (unsigned long)get_capacity(disk)/2048,
814 p->cyl, p->head, p->sect);
815 }
816
817 if (request_irq(HD_IRQ, hd_interrupt, SA_INTERRUPT, "hd", NULL)) {
818 printk("hd: unable to get IRQ%d for the hard disk driver\n",
819 HD_IRQ);
820 goto out1;
821 }
822 if (!request_region(HD_DATA, 8, "hd")) {
823 printk(KERN_WARNING "hd: port 0x%x busy\n", HD_DATA);
824 goto out2;
825 }
826 if (!request_region(HD_CMD, 1, "hd(cmd)")) {
827 printk(KERN_WARNING "hd: port 0x%x busy\n", HD_CMD);
828 goto out3;
829 }
830
831 /* Let them fly */
832 for(drive=0; drive < NR_HD; drive++)
833 add_disk(hd_gendisk[drive]);
834
835 return 0;
836
837out3:
838 release_region(HD_DATA, 8);
839out2:
840 free_irq(HD_IRQ, NULL);
841out1:
842 for (drive = 0; drive < NR_HD; drive++)
843 put_disk(hd_gendisk[drive]);
844 NR_HD = 0;
845out:
846 del_timer(&device_timer);
847 unregister_blkdev(MAJOR_NR,"hd");
848 blk_cleanup_queue(hd_queue);
849 return -1;
850Enomem:
851 while (drive--)
852 put_disk(hd_gendisk[drive]);
853 goto out;
854}
855
maximilian attemsfca44802005-04-16 15:25:52 -0700856static int __init parse_hd_setup (char *line) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857 int ints[6];
858
859 (void) get_options(line, ARRAY_SIZE(ints), ints);
860 hd_setup(NULL, ints);
861
862 return 1;
863}
864__setup("hd=", parse_hd_setup);
865
866module_init(hd_init);