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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/ide/legacy/hd.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/ide/legacy/hd.c')
-rw-r--r--drivers/ide/legacy/hd.c864
1 files changed, 864 insertions, 0 deletions
diff --git a/drivers/ide/legacy/hd.c b/drivers/ide/legacy/hd.c
new file mode 100644
index 000000000000..c4090550ec13
--- /dev/null
+++ b/drivers/ide/legacy/hd.c
@@ -0,0 +1,864 @@
1/*
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)
159unsigned long last_req;
160
161unsigned long read_timer(void)
162{
163 extern spinlock_t i8253_lock;
164 unsigned long t, flags;
165 int i;
166
167 spin_lock_irqsave(&i8253_lock, flags);
168 t = jiffies * 11932;
169 outb_p(0, 0x43);
170 i = inb_p(0x40);
171 i |= inb(0x40) << 8;
172 spin_unlock_irqrestore(&i8253_lock, flags);
173 return(t - i);
174}
175#endif
176
177static void __init hd_setup(char *str, int *ints)
178{
179 int hdind = 0;
180
181 if (ints[0] != 3)
182 return;
183 if (hd_info[0].head != 0)
184 hdind=1;
185 hd_info[hdind].head = ints[2];
186 hd_info[hdind].sect = ints[3];
187 hd_info[hdind].cyl = ints[1];
188 hd_info[hdind].wpcom = 0;
189 hd_info[hdind].lzone = ints[1];
190 hd_info[hdind].ctl = (ints[2] > 8 ? 8 : 0);
191 NR_HD = hdind+1;
192}
193
194static void dump_status (const char *msg, unsigned int stat)
195{
196 char *name = "hd?";
197 if (CURRENT)
198 name = CURRENT->rq_disk->disk_name;
199
200#ifdef VERBOSE_ERRORS
201 printk("%s: %s: status=0x%02x { ", name, msg, stat & 0xff);
202 if (stat & BUSY_STAT) printk("Busy ");
203 if (stat & READY_STAT) printk("DriveReady ");
204 if (stat & WRERR_STAT) printk("WriteFault ");
205 if (stat & SEEK_STAT) printk("SeekComplete ");
206 if (stat & DRQ_STAT) printk("DataRequest ");
207 if (stat & ECC_STAT) printk("CorrectedError ");
208 if (stat & INDEX_STAT) printk("Index ");
209 if (stat & ERR_STAT) printk("Error ");
210 printk("}\n");
211 if ((stat & ERR_STAT) == 0) {
212 hd_error = 0;
213 } else {
214 hd_error = inb(HD_ERROR);
215 printk("%s: %s: error=0x%02x { ", name, msg, hd_error & 0xff);
216 if (hd_error & BBD_ERR) printk("BadSector ");
217 if (hd_error & ECC_ERR) printk("UncorrectableError ");
218 if (hd_error & ID_ERR) printk("SectorIdNotFound ");
219 if (hd_error & ABRT_ERR) printk("DriveStatusError ");
220 if (hd_error & TRK0_ERR) printk("TrackZeroNotFound ");
221 if (hd_error & MARK_ERR) printk("AddrMarkNotFound ");
222 printk("}");
223 if (hd_error & (BBD_ERR|ECC_ERR|ID_ERR|MARK_ERR)) {
224 printk(", CHS=%d/%d/%d", (inb(HD_HCYL)<<8) + inb(HD_LCYL),
225 inb(HD_CURRENT) & 0xf, inb(HD_SECTOR));
226 if (CURRENT)
227 printk(", sector=%ld", CURRENT->sector);
228 }
229 printk("\n");
230 }
231#else
232 printk("%s: %s: status=0x%02x.\n", name, msg, stat & 0xff);
233 if ((stat & ERR_STAT) == 0) {
234 hd_error = 0;
235 } else {
236 hd_error = inb(HD_ERROR);
237 printk("%s: %s: error=0x%02x.\n", name, msg, hd_error & 0xff);
238 }
239#endif
240}
241
242static void check_status(void)
243{
244 int i = inb_p(HD_STATUS);
245
246 if (!OK_STATUS(i)) {
247 dump_status("check_status", i);
248 bad_rw_intr();
249 }
250}
251
252static int controller_busy(void)
253{
254 int retries = 100000;
255 unsigned char status;
256
257 do {
258 status = inb_p(HD_STATUS);
259 } while ((status & BUSY_STAT) && --retries);
260 return status;
261}
262
263static int status_ok(void)
264{
265 unsigned char status = inb_p(HD_STATUS);
266
267 if (status & BUSY_STAT)
268 return 1; /* Ancient, but does it make sense??? */
269 if (status & WRERR_STAT)
270 return 0;
271 if (!(status & READY_STAT))
272 return 0;
273 if (!(status & SEEK_STAT))
274 return 0;
275 return 1;
276}
277
278static int controller_ready(unsigned int drive, unsigned int head)
279{
280 int retry = 100;
281
282 do {
283 if (controller_busy() & BUSY_STAT)
284 return 0;
285 outb_p(0xA0 | (drive<<4) | head, HD_CURRENT);
286 if (status_ok())
287 return 1;
288 } while (--retry);
289 return 0;
290}
291
292
293static void hd_out(struct hd_i_struct *disk,
294 unsigned int nsect,
295 unsigned int sect,
296 unsigned int head,
297 unsigned int cyl,
298 unsigned int cmd,
299 void (*intr_addr)(void))
300{
301 unsigned short port;
302
303#if (HD_DELAY > 0)
304 while (read_timer() - last_req < HD_DELAY)
305 /* nothing */;
306#endif
307 if (reset)
308 return;
309 if (!controller_ready(disk->unit, head)) {
310 reset = 1;
311 return;
312 }
313 SET_HANDLER(intr_addr);
314 outb_p(disk->ctl,HD_CMD);
315 port=HD_DATA;
316 outb_p(disk->wpcom>>2,++port);
317 outb_p(nsect,++port);
318 outb_p(sect,++port);
319 outb_p(cyl,++port);
320 outb_p(cyl>>8,++port);
321 outb_p(0xA0|(disk->unit<<4)|head,++port);
322 outb_p(cmd,++port);
323}
324
325static void hd_request (void);
326
327static int drive_busy(void)
328{
329 unsigned int i;
330 unsigned char c;
331
332 for (i = 0; i < 500000 ; i++) {
333 c = inb_p(HD_STATUS);
334 if ((c & (BUSY_STAT | READY_STAT | SEEK_STAT)) == STAT_OK)
335 return 0;
336 }
337 dump_status("reset timed out", c);
338 return 1;
339}
340
341static void reset_controller(void)
342{
343 int i;
344
345 outb_p(4,HD_CMD);
346 for(i = 0; i < 1000; i++) barrier();
347 outb_p(hd_info[0].ctl & 0x0f,HD_CMD);
348 for(i = 0; i < 1000; i++) barrier();
349 if (drive_busy())
350 printk("hd: controller still busy\n");
351 else if ((hd_error = inb(HD_ERROR)) != 1)
352 printk("hd: controller reset failed: %02x\n",hd_error);
353}
354
355static void reset_hd(void)
356{
357 static int i;
358
359repeat:
360 if (reset) {
361 reset = 0;
362 i = -1;
363 reset_controller();
364 } else {
365 check_status();
366 if (reset)
367 goto repeat;
368 }
369 if (++i < NR_HD) {
370 struct hd_i_struct *disk = &hd_info[i];
371 disk->special_op = disk->recalibrate = 1;
372 hd_out(disk,disk->sect,disk->sect,disk->head-1,
373 disk->cyl,WIN_SPECIFY,&reset_hd);
374 if (reset)
375 goto repeat;
376 } else
377 hd_request();
378}
379
380/*
381 * Ok, don't know what to do with the unexpected interrupts: on some machines
382 * doing a reset and a retry seems to result in an eternal loop. Right now I
383 * ignore it, and just set the timeout.
384 *
385 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever the
386 * drive enters "idle", "standby", or "sleep" mode, so if the status looks
387 * "good", we just ignore the interrupt completely.
388 */
389static void unexpected_hd_interrupt(void)
390{
391 unsigned int stat = inb_p(HD_STATUS);
392
393 if (stat & (BUSY_STAT|DRQ_STAT|ECC_STAT|ERR_STAT)) {
394 dump_status ("unexpected interrupt", stat);
395 SET_TIMER;
396 }
397}
398
399/*
400 * bad_rw_intr() now tries to be a bit smarter and does things
401 * according to the error returned by the controller.
402 * -Mika Liljeberg (liljeber@cs.Helsinki.FI)
403 */
404static void bad_rw_intr(void)
405{
406 struct request *req = CURRENT;
407 if (req != NULL) {
408 struct hd_i_struct *disk = req->rq_disk->private_data;
409 if (++req->errors >= MAX_ERRORS || (hd_error & BBD_ERR)) {
410 end_request(req, 0);
411 disk->special_op = disk->recalibrate = 1;
412 } else if (req->errors % RESET_FREQ == 0)
413 reset = 1;
414 else if ((hd_error & TRK0_ERR) || req->errors % RECAL_FREQ == 0)
415 disk->special_op = disk->recalibrate = 1;
416 /* Otherwise just retry */
417 }
418}
419
420static inline int wait_DRQ(void)
421{
422 int retries = 100000, stat;
423
424 while (--retries > 0)
425 if ((stat = inb_p(HD_STATUS)) & DRQ_STAT)
426 return 0;
427 dump_status("wait_DRQ", stat);
428 return -1;
429}
430
431static void read_intr(void)
432{
433 struct request *req;
434 int i, retries = 100000;
435
436 do {
437 i = (unsigned) inb_p(HD_STATUS);
438 if (i & BUSY_STAT)
439 continue;
440 if (!OK_STATUS(i))
441 break;
442 if (i & DRQ_STAT)
443 goto ok_to_read;
444 } while (--retries > 0);
445 dump_status("read_intr", i);
446 bad_rw_intr();
447 hd_request();
448 return;
449ok_to_read:
450 req = CURRENT;
451 insw(HD_DATA,req->buffer,256);
452 req->sector++;
453 req->buffer += 512;
454 req->errors = 0;
455 i = --req->nr_sectors;
456 --req->current_nr_sectors;
457#ifdef DEBUG
458 printk("%s: read: sector %ld, remaining = %ld, buffer=%p\n",
459 req->rq_disk->disk_name, req->sector, req->nr_sectors,
460 req->buffer+512));
461#endif
462 if (req->current_nr_sectors <= 0)
463 end_request(req, 1);
464 if (i > 0) {
465 SET_HANDLER(&read_intr);
466 return;
467 }
468 (void) inb_p(HD_STATUS);
469#if (HD_DELAY > 0)
470 last_req = read_timer();
471#endif
472 if (elv_next_request(QUEUE))
473 hd_request();
474 return;
475}
476
477static void write_intr(void)
478{
479 struct request *req = CURRENT;
480 int i;
481 int retries = 100000;
482
483 do {
484 i = (unsigned) inb_p(HD_STATUS);
485 if (i & BUSY_STAT)
486 continue;
487 if (!OK_STATUS(i))
488 break;
489 if ((req->nr_sectors <= 1) || (i & DRQ_STAT))
490 goto ok_to_write;
491 } while (--retries > 0);
492 dump_status("write_intr", i);
493 bad_rw_intr();
494 hd_request();
495 return;
496ok_to_write:
497 req->sector++;
498 i = --req->nr_sectors;
499 --req->current_nr_sectors;
500 req->buffer += 512;
501 if (!i || (req->bio && req->current_nr_sectors <= 0))
502 end_request(req, 1);
503 if (i > 0) {
504 SET_HANDLER(&write_intr);
505 outsw(HD_DATA,req->buffer,256);
506 local_irq_enable();
507 } else {
508#if (HD_DELAY > 0)
509 last_req = read_timer();
510#endif
511 hd_request();
512 }
513 return;
514}
515
516static void recal_intr(void)
517{
518 check_status();
519#if (HD_DELAY > 0)
520 last_req = read_timer();
521#endif
522 hd_request();
523}
524
525/*
526 * This is another of the error-routines I don't know what to do with. The
527 * best idea seems to just set reset, and start all over again.
528 */
529static void hd_times_out(unsigned long dummy)
530{
531 char *name;
532
533 do_hd = NULL;
534
535 if (!CURRENT)
536 return;
537
538 disable_irq(HD_IRQ);
539 local_irq_enable();
540 reset = 1;
541 name = CURRENT->rq_disk->disk_name;
542 printk("%s: timeout\n", name);
543 if (++CURRENT->errors >= MAX_ERRORS) {
544#ifdef DEBUG
545 printk("%s: too many errors\n", name);
546#endif
547 end_request(CURRENT, 0);
548 }
549 local_irq_disable();
550 hd_request();
551 enable_irq(HD_IRQ);
552}
553
554static int do_special_op(struct hd_i_struct *disk, struct request *req)
555{
556 if (disk->recalibrate) {
557 disk->recalibrate = 0;
558 hd_out(disk,disk->sect,0,0,0,WIN_RESTORE,&recal_intr);
559 return reset;
560 }
561 if (disk->head > 16) {
562 printk ("%s: cannot handle device with more than 16 heads - giving up\n", req->rq_disk->disk_name);
563 end_request(req, 0);
564 }
565 disk->special_op = 0;
566 return 1;
567}
568
569/*
570 * The driver enables interrupts as much as possible. In order to do this,
571 * (a) the device-interrupt is disabled before entering hd_request(),
572 * and (b) the timeout-interrupt is disabled before the sti().
573 *
574 * Interrupts are still masked (by default) whenever we are exchanging
575 * data/cmds with a drive, because some drives seem to have very poor
576 * tolerance for latency during I/O. The IDE driver has support to unmask
577 * interrupts for non-broken hardware, so use that driver if required.
578 */
579static void hd_request(void)
580{
581 unsigned int block, nsect, sec, track, head, cyl;
582 struct hd_i_struct *disk;
583 struct request *req;
584
585 if (do_hd)
586 return;
587repeat:
588 del_timer(&device_timer);
589 local_irq_enable();
590
591 req = CURRENT;
592 if (!req) {
593 do_hd = NULL;
594 return;
595 }
596
597 if (reset) {
598 local_irq_disable();
599 reset_hd();
600 return;
601 }
602 disk = req->rq_disk->private_data;
603 block = req->sector;
604 nsect = req->nr_sectors;
605 if (block >= get_capacity(req->rq_disk) ||
606 ((block+nsect) > get_capacity(req->rq_disk))) {
607 printk("%s: bad access: block=%d, count=%d\n",
608 req->rq_disk->disk_name, block, nsect);
609 end_request(req, 0);
610 goto repeat;
611 }
612
613 if (disk->special_op) {
614 if (do_special_op(disk, req))
615 goto repeat;
616 return;
617 }
618 sec = block % disk->sect + 1;
619 track = block / disk->sect;
620 head = track % disk->head;
621 cyl = track / disk->head;
622#ifdef DEBUG
623 printk("%s: %sing: CHS=%d/%d/%d, sectors=%d, buffer=%p\n",
624 req->rq_disk->disk_name, (req->cmd == READ)?"read":"writ",
625 cyl, head, sec, nsect, req->buffer);
626#endif
627 if (req->flags & REQ_CMD) {
628 switch (rq_data_dir(req)) {
629 case READ:
630 hd_out(disk,nsect,sec,head,cyl,WIN_READ,&read_intr);
631 if (reset)
632 goto repeat;
633 break;
634 case WRITE:
635 hd_out(disk,nsect,sec,head,cyl,WIN_WRITE,&write_intr);
636 if (reset)
637 goto repeat;
638 if (wait_DRQ()) {
639 bad_rw_intr();
640 goto repeat;
641 }
642 outsw(HD_DATA,req->buffer,256);
643 break;
644 default:
645 printk("unknown hd-command\n");
646 end_request(req, 0);
647 break;
648 }
649 }
650}
651
652static void do_hd_request (request_queue_t * q)
653{
654 disable_irq(HD_IRQ);
655 hd_request();
656 enable_irq(HD_IRQ);
657}
658
659static int hd_ioctl(struct inode * inode, struct file * file,
660 unsigned int cmd, unsigned long arg)
661{
662 struct hd_i_struct *disk = inode->i_bdev->bd_disk->private_data;
663 struct hd_geometry __user *loc = (struct hd_geometry __user *) arg;
664 struct hd_geometry g;
665
666 if (cmd != HDIO_GETGEO)
667 return -EINVAL;
668 if (!loc)
669 return -EINVAL;
670 g.heads = disk->head;
671 g.sectors = disk->sect;
672 g.cylinders = disk->cyl;
673 g.start = get_start_sect(inode->i_bdev);
674 return copy_to_user(loc, &g, sizeof g) ? -EFAULT : 0;
675}
676
677/*
678 * Releasing a block device means we sync() it, so that it can safely
679 * be forgotten about...
680 */
681
682static irqreturn_t hd_interrupt(int irq, void *dev_id, struct pt_regs *regs)
683{
684 void (*handler)(void) = do_hd;
685
686 do_hd = NULL;
687 del_timer(&device_timer);
688 if (!handler)
689 handler = unexpected_hd_interrupt;
690 handler();
691 local_irq_enable();
692 return IRQ_HANDLED;
693}
694
695static struct block_device_operations hd_fops = {
696 .ioctl = hd_ioctl,
697};
698
699/*
700 * This is the hard disk IRQ description. The SA_INTERRUPT in sa_flags
701 * means we run the IRQ-handler with interrupts disabled: this is bad for
702 * interrupt latency, but anything else has led to problems on some
703 * machines.
704 *
705 * We enable interrupts in some of the routines after making sure it's
706 * safe.
707 */
708
709static int __init hd_init(void)
710{
711 int drive;
712
713 if (register_blkdev(MAJOR_NR,"hd"))
714 return -1;
715
716 hd_queue = blk_init_queue(do_hd_request, &hd_lock);
717 if (!hd_queue) {
718 unregister_blkdev(MAJOR_NR,"hd");
719 return -ENOMEM;
720 }
721
722 blk_queue_max_sectors(hd_queue, 255);
723 init_timer(&device_timer);
724 device_timer.function = hd_times_out;
725 blk_queue_hardsect_size(hd_queue, 512);
726
727#ifdef __i386__
728 if (!NR_HD) {
729 extern struct drive_info drive_info;
730 unsigned char *BIOS = (unsigned char *) &drive_info;
731 unsigned long flags;
732 int cmos_disks;
733
734 for (drive=0 ; drive<2 ; drive++) {
735 hd_info[drive].cyl = *(unsigned short *) BIOS;
736 hd_info[drive].head = *(2+BIOS);
737 hd_info[drive].wpcom = *(unsigned short *) (5+BIOS);
738 hd_info[drive].ctl = *(8+BIOS);
739 hd_info[drive].lzone = *(unsigned short *) (12+BIOS);
740 hd_info[drive].sect = *(14+BIOS);
741#ifdef does_not_work_for_everybody_with_scsi_but_helps_ibm_vp
742 if (hd_info[drive].cyl && NR_HD == drive)
743 NR_HD++;
744#endif
745 BIOS += 16;
746 }
747
748 /*
749 We query CMOS about hard disks : it could be that
750 we have a SCSI/ESDI/etc controller that is BIOS
751 compatible with ST-506, and thus showing up in our
752 BIOS table, but not register compatible, and therefore
753 not present in CMOS.
754
755 Furthermore, we will assume that our ST-506 drives
756 <if any> are the primary drives in the system, and
757 the ones reflected as drive 1 or 2.
758
759 The first drive is stored in the high nibble of CMOS
760 byte 0x12, the second in the low nibble. This will be
761 either a 4 bit drive type or 0xf indicating use byte 0x19
762 for an 8 bit type, drive 1, 0x1a for drive 2 in CMOS.
763
764 Needless to say, a non-zero value means we have
765 an AT controller hard disk for that drive.
766
767 Currently the rtc_lock is a bit academic since this
768 driver is non-modular, but someday... ? Paul G.
769 */
770
771 spin_lock_irqsave(&rtc_lock, flags);
772 cmos_disks = CMOS_READ(0x12);
773 spin_unlock_irqrestore(&rtc_lock, flags);
774
775 if (cmos_disks & 0xf0) {
776 if (cmos_disks & 0x0f)
777 NR_HD = 2;
778 else
779 NR_HD = 1;
780 }
781 }
782#endif /* __i386__ */
783#ifdef __arm__
784 if (!NR_HD) {
785 /* We don't know anything about the drive. This means
786 * that you *MUST* specify the drive parameters to the
787 * kernel yourself.
788 */
789 printk("hd: no drives specified - use hd=cyl,head,sectors"
790 " on kernel command line\n");
791 }
792#endif
793 if (!NR_HD)
794 goto out;
795
796 for (drive=0 ; drive < NR_HD ; drive++) {
797 struct gendisk *disk = alloc_disk(64);
798 struct hd_i_struct *p = &hd_info[drive];
799 if (!disk)
800 goto Enomem;
801 disk->major = MAJOR_NR;
802 disk->first_minor = drive << 6;
803 disk->fops = &hd_fops;
804 sprintf(disk->disk_name, "hd%c", 'a'+drive);
805 disk->private_data = p;
806 set_capacity(disk, p->head * p->sect * p->cyl);
807 disk->queue = hd_queue;
808 p->unit = drive;
809 hd_gendisk[drive] = disk;
810 printk ("%s: %luMB, CHS=%d/%d/%d\n",
811 disk->disk_name, (unsigned long)get_capacity(disk)/2048,
812 p->cyl, p->head, p->sect);
813 }
814
815 if (request_irq(HD_IRQ, hd_interrupt, SA_INTERRUPT, "hd", NULL)) {
816 printk("hd: unable to get IRQ%d for the hard disk driver\n",
817 HD_IRQ);
818 goto out1;
819 }
820 if (!request_region(HD_DATA, 8, "hd")) {
821 printk(KERN_WARNING "hd: port 0x%x busy\n", HD_DATA);
822 goto out2;
823 }
824 if (!request_region(HD_CMD, 1, "hd(cmd)")) {
825 printk(KERN_WARNING "hd: port 0x%x busy\n", HD_CMD);
826 goto out3;
827 }
828
829 /* Let them fly */
830 for(drive=0; drive < NR_HD; drive++)
831 add_disk(hd_gendisk[drive]);
832
833 return 0;
834
835out3:
836 release_region(HD_DATA, 8);
837out2:
838 free_irq(HD_IRQ, NULL);
839out1:
840 for (drive = 0; drive < NR_HD; drive++)
841 put_disk(hd_gendisk[drive]);
842 NR_HD = 0;
843out:
844 del_timer(&device_timer);
845 unregister_blkdev(MAJOR_NR,"hd");
846 blk_cleanup_queue(hd_queue);
847 return -1;
848Enomem:
849 while (drive--)
850 put_disk(hd_gendisk[drive]);
851 goto out;
852}
853
854static int parse_hd_setup (char *line) {
855 int ints[6];
856
857 (void) get_options(line, ARRAY_SIZE(ints), ints);
858 hd_setup(NULL, ints);
859
860 return 1;
861}
862__setup("hd=", parse_hd_setup);
863
864module_init(hd_init);