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/string.h>
38 #include <linux/ioport.h>
39 #include <linux/init.h>
40 #include <linux/blkpg.h>
41 #include <linux/ata.h>
42 #include <linux/hdreg.h>
43
44 #define HD_IRQ 14
45
46 #define REALLY_SLOW_IO
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
97 static DEFINE_SPINLOCK(hd_lock);
98 static struct request_queue *hd_queue;
99 static struct request *hd_req;
100
101 #define TIMEOUT_VALUE (6*HZ)
102 #define HD_DELAY 0
103
104 #define MAX_ERRORS 16 /* Max read/write errors/sector */
105 #define RESET_FREQ 8 /* Reset controller every 8th retry */
106 #define RECAL_FREQ 4 /* Recalibrate every 4th retry */
107 #define MAX_HD 2
108
109 #define STAT_OK (READY_STAT|SEEK_STAT)
110 #define OK_STATUS(s) (((s)&(STAT_OK|(BUSY_STAT|WRERR_STAT|ERR_STAT)))==STAT_OK)
111
112 static void recal_intr(void);
113 static void bad_rw_intr(void);
114
115 static int reset;
116 static int hd_error;
117
118 /*
119 * This struct defines the HD's and their types.
120 */
121 struct hd_i_struct {
122 unsigned int head, sect, cyl, wpcom, lzone, ctl;
123 int unit;
124 int recalibrate;
125 int special_op;
126 };
127
128 #ifdef HD_TYPE
129 static struct hd_i_struct hd_info[] = { HD_TYPE };
130 static int NR_HD = ARRAY_SIZE(hd_info);
131 #else
132 static struct hd_i_struct hd_info[MAX_HD];
133 static int NR_HD;
134 #endif
135
136 static struct gendisk *hd_gendisk[MAX_HD];
137
138 static struct timer_list device_timer;
139
140 #define TIMEOUT_VALUE (6*HZ)
141
142 #define SET_TIMER \
143 do { \
144 mod_timer(&device_timer, jiffies + TIMEOUT_VALUE); \
145 } while (0)
146
147 static void (*do_hd)(void) = NULL;
148 #define SET_HANDLER(x) \
149 if ((do_hd = (x)) != NULL) \
150 SET_TIMER; \
151 else \
152 del_timer(&device_timer);
153
154
155 #if (HD_DELAY > 0)
156
157 #include <linux/i8253.h>
158
159 unsigned long last_req;
160
read_timer(void)161 unsigned long read_timer(void)
162 {
163 unsigned long t, flags;
164 int i;
165
166 raw_spin_lock_irqsave(&i8253_lock, flags);
167 t = jiffies * 11932;
168 outb_p(0, 0x43);
169 i = inb_p(0x40);
170 i |= inb(0x40) << 8;
171 raw_spin_unlock_irqrestore(&i8253_lock, flags);
172 return(t - i);
173 }
174 #endif
175
hd_setup(char * str,int * ints)176 static void __init hd_setup(char *str, int *ints)
177 {
178 int hdind = 0;
179
180 if (ints[0] != 3)
181 return;
182 if (hd_info[0].head != 0)
183 hdind = 1;
184 hd_info[hdind].head = ints[2];
185 hd_info[hdind].sect = ints[3];
186 hd_info[hdind].cyl = ints[1];
187 hd_info[hdind].wpcom = 0;
188 hd_info[hdind].lzone = ints[1];
189 hd_info[hdind].ctl = (ints[2] > 8 ? 8 : 0);
190 NR_HD = hdind+1;
191 }
192
hd_end_request(int err,unsigned int bytes)193 static bool hd_end_request(int err, unsigned int bytes)
194 {
195 if (__blk_end_request(hd_req, err, bytes))
196 return true;
197 hd_req = NULL;
198 return false;
199 }
200
hd_end_request_cur(int err)201 static bool hd_end_request_cur(int err)
202 {
203 return hd_end_request(err, blk_rq_cur_bytes(hd_req));
204 }
205
dump_status(const char * msg,unsigned int stat)206 static void dump_status(const char *msg, unsigned int stat)
207 {
208 char *name = "hd?";
209 if (hd_req)
210 name = hd_req->rq_disk->disk_name;
211
212 #ifdef VERBOSE_ERRORS
213 printk("%s: %s: status=0x%02x { ", name, msg, stat & 0xff);
214 if (stat & BUSY_STAT) printk("Busy ");
215 if (stat & READY_STAT) printk("DriveReady ");
216 if (stat & WRERR_STAT) printk("WriteFault ");
217 if (stat & SEEK_STAT) printk("SeekComplete ");
218 if (stat & DRQ_STAT) printk("DataRequest ");
219 if (stat & ECC_STAT) printk("CorrectedError ");
220 if (stat & INDEX_STAT) printk("Index ");
221 if (stat & ERR_STAT) printk("Error ");
222 printk("}\n");
223 if ((stat & ERR_STAT) == 0) {
224 hd_error = 0;
225 } else {
226 hd_error = inb(HD_ERROR);
227 printk("%s: %s: error=0x%02x { ", name, msg, hd_error & 0xff);
228 if (hd_error & BBD_ERR) printk("BadSector ");
229 if (hd_error & ECC_ERR) printk("UncorrectableError ");
230 if (hd_error & ID_ERR) printk("SectorIdNotFound ");
231 if (hd_error & ABRT_ERR) printk("DriveStatusError ");
232 if (hd_error & TRK0_ERR) printk("TrackZeroNotFound ");
233 if (hd_error & MARK_ERR) printk("AddrMarkNotFound ");
234 printk("}");
235 if (hd_error & (BBD_ERR|ECC_ERR|ID_ERR|MARK_ERR)) {
236 printk(", CHS=%d/%d/%d", (inb(HD_HCYL)<<8) + inb(HD_LCYL),
237 inb(HD_CURRENT) & 0xf, inb(HD_SECTOR));
238 if (hd_req)
239 printk(", sector=%ld", blk_rq_pos(hd_req));
240 }
241 printk("\n");
242 }
243 #else
244 printk("%s: %s: status=0x%02x.\n", name, msg, stat & 0xff);
245 if ((stat & ERR_STAT) == 0) {
246 hd_error = 0;
247 } else {
248 hd_error = inb(HD_ERROR);
249 printk("%s: %s: error=0x%02x.\n", name, msg, hd_error & 0xff);
250 }
251 #endif
252 }
253
check_status(void)254 static void check_status(void)
255 {
256 int i = inb_p(HD_STATUS);
257
258 if (!OK_STATUS(i)) {
259 dump_status("check_status", i);
260 bad_rw_intr();
261 }
262 }
263
controller_busy(void)264 static int controller_busy(void)
265 {
266 int retries = 100000;
267 unsigned char status;
268
269 do {
270 status = inb_p(HD_STATUS);
271 } while ((status & BUSY_STAT) && --retries);
272 return status;
273 }
274
status_ok(void)275 static int status_ok(void)
276 {
277 unsigned char status = inb_p(HD_STATUS);
278
279 if (status & BUSY_STAT)
280 return 1; /* Ancient, but does it make sense??? */
281 if (status & WRERR_STAT)
282 return 0;
283 if (!(status & READY_STAT))
284 return 0;
285 if (!(status & SEEK_STAT))
286 return 0;
287 return 1;
288 }
289
controller_ready(unsigned int drive,unsigned int head)290 static int controller_ready(unsigned int drive, unsigned int head)
291 {
292 int retry = 100;
293
294 do {
295 if (controller_busy() & BUSY_STAT)
296 return 0;
297 outb_p(0xA0 | (drive<<4) | head, HD_CURRENT);
298 if (status_ok())
299 return 1;
300 } while (--retry);
301 return 0;
302 }
303
hd_out(struct hd_i_struct * disk,unsigned int nsect,unsigned int sect,unsigned int head,unsigned int cyl,unsigned int cmd,void (* intr_addr)(void))304 static void hd_out(struct hd_i_struct *disk,
305 unsigned int nsect,
306 unsigned int sect,
307 unsigned int head,
308 unsigned int cyl,
309 unsigned int cmd,
310 void (*intr_addr)(void))
311 {
312 unsigned short port;
313
314 #if (HD_DELAY > 0)
315 while (read_timer() - last_req < HD_DELAY)
316 /* nothing */;
317 #endif
318 if (reset)
319 return;
320 if (!controller_ready(disk->unit, head)) {
321 reset = 1;
322 return;
323 }
324 SET_HANDLER(intr_addr);
325 outb_p(disk->ctl, HD_CMD);
326 port = HD_DATA;
327 outb_p(disk->wpcom >> 2, ++port);
328 outb_p(nsect, ++port);
329 outb_p(sect, ++port);
330 outb_p(cyl, ++port);
331 outb_p(cyl >> 8, ++port);
332 outb_p(0xA0 | (disk->unit << 4) | head, ++port);
333 outb_p(cmd, ++port);
334 }
335
336 static void hd_request (void);
337
drive_busy(void)338 static int drive_busy(void)
339 {
340 unsigned int i;
341 unsigned char c;
342
343 for (i = 0; i < 500000 ; i++) {
344 c = inb_p(HD_STATUS);
345 if ((c & (BUSY_STAT | READY_STAT | SEEK_STAT)) == STAT_OK)
346 return 0;
347 }
348 dump_status("reset timed out", c);
349 return 1;
350 }
351
reset_controller(void)352 static void reset_controller(void)
353 {
354 int i;
355
356 outb_p(4, HD_CMD);
357 for (i = 0; i < 1000; i++) barrier();
358 outb_p(hd_info[0].ctl & 0x0f, HD_CMD);
359 for (i = 0; i < 1000; i++) barrier();
360 if (drive_busy())
361 printk("hd: controller still busy\n");
362 else if ((hd_error = inb(HD_ERROR)) != 1)
363 printk("hd: controller reset failed: %02x\n", hd_error);
364 }
365
reset_hd(void)366 static void reset_hd(void)
367 {
368 static int i;
369
370 repeat:
371 if (reset) {
372 reset = 0;
373 i = -1;
374 reset_controller();
375 } else {
376 check_status();
377 if (reset)
378 goto repeat;
379 }
380 if (++i < NR_HD) {
381 struct hd_i_struct *disk = &hd_info[i];
382 disk->special_op = disk->recalibrate = 1;
383 hd_out(disk, disk->sect, disk->sect, disk->head-1,
384 disk->cyl, ATA_CMD_INIT_DEV_PARAMS, &reset_hd);
385 if (reset)
386 goto repeat;
387 } else
388 hd_request();
389 }
390
391 /*
392 * Ok, don't know what to do with the unexpected interrupts: on some machines
393 * doing a reset and a retry seems to result in an eternal loop. Right now I
394 * ignore it, and just set the timeout.
395 *
396 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever the
397 * drive enters "idle", "standby", or "sleep" mode, so if the status looks
398 * "good", we just ignore the interrupt completely.
399 */
unexpected_hd_interrupt(void)400 static void unexpected_hd_interrupt(void)
401 {
402 unsigned int stat = inb_p(HD_STATUS);
403
404 if (stat & (BUSY_STAT|DRQ_STAT|ECC_STAT|ERR_STAT)) {
405 dump_status("unexpected interrupt", stat);
406 SET_TIMER;
407 }
408 }
409
410 /*
411 * bad_rw_intr() now tries to be a bit smarter and does things
412 * according to the error returned by the controller.
413 * -Mika Liljeberg (liljeber@cs.Helsinki.FI)
414 */
bad_rw_intr(void)415 static void bad_rw_intr(void)
416 {
417 struct request *req = hd_req;
418
419 if (req != NULL) {
420 struct hd_i_struct *disk = req->rq_disk->private_data;
421 if (++req->errors >= MAX_ERRORS || (hd_error & BBD_ERR)) {
422 hd_end_request_cur(-EIO);
423 disk->special_op = disk->recalibrate = 1;
424 } else if (req->errors % RESET_FREQ == 0)
425 reset = 1;
426 else if ((hd_error & TRK0_ERR) || req->errors % RECAL_FREQ == 0)
427 disk->special_op = disk->recalibrate = 1;
428 /* Otherwise just retry */
429 }
430 }
431
wait_DRQ(void)432 static inline int wait_DRQ(void)
433 {
434 int retries;
435 int stat;
436
437 for (retries = 0; retries < 100000; retries++) {
438 stat = inb_p(HD_STATUS);
439 if (stat & DRQ_STAT)
440 return 0;
441 }
442 dump_status("wait_DRQ", stat);
443 return -1;
444 }
445
read_intr(void)446 static void read_intr(void)
447 {
448 struct request *req;
449 int i, retries = 100000;
450
451 do {
452 i = (unsigned) inb_p(HD_STATUS);
453 if (i & BUSY_STAT)
454 continue;
455 if (!OK_STATUS(i))
456 break;
457 if (i & DRQ_STAT)
458 goto ok_to_read;
459 } while (--retries > 0);
460 dump_status("read_intr", i);
461 bad_rw_intr();
462 hd_request();
463 return;
464
465 ok_to_read:
466 req = hd_req;
467 insw(HD_DATA, req->buffer, 256);
468 #ifdef DEBUG
469 printk("%s: read: sector %ld, remaining = %u, buffer=%p\n",
470 req->rq_disk->disk_name, blk_rq_pos(req) + 1,
471 blk_rq_sectors(req) - 1, req->buffer+512);
472 #endif
473 if (hd_end_request(0, 512)) {
474 SET_HANDLER(&read_intr);
475 return;
476 }
477
478 (void) inb_p(HD_STATUS);
479 #if (HD_DELAY > 0)
480 last_req = read_timer();
481 #endif
482 hd_request();
483 }
484
write_intr(void)485 static void write_intr(void)
486 {
487 struct request *req = hd_req;
488 int i;
489 int retries = 100000;
490
491 do {
492 i = (unsigned) inb_p(HD_STATUS);
493 if (i & BUSY_STAT)
494 continue;
495 if (!OK_STATUS(i))
496 break;
497 if ((blk_rq_sectors(req) <= 1) || (i & DRQ_STAT))
498 goto ok_to_write;
499 } while (--retries > 0);
500 dump_status("write_intr", i);
501 bad_rw_intr();
502 hd_request();
503 return;
504
505 ok_to_write:
506 if (hd_end_request(0, 512)) {
507 SET_HANDLER(&write_intr);
508 outsw(HD_DATA, req->buffer, 256);
509 return;
510 }
511
512 #if (HD_DELAY > 0)
513 last_req = read_timer();
514 #endif
515 hd_request();
516 }
517
recal_intr(void)518 static 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 */
hd_times_out(unsigned long dummy)531 static void hd_times_out(unsigned long dummy)
532 {
533 char *name;
534
535 do_hd = NULL;
536
537 if (!hd_req)
538 return;
539
540 spin_lock_irq(hd_queue->queue_lock);
541 reset = 1;
542 name = hd_req->rq_disk->disk_name;
543 printk("%s: timeout\n", name);
544 if (++hd_req->errors >= MAX_ERRORS) {
545 #ifdef DEBUG
546 printk("%s: too many errors\n", name);
547 #endif
548 hd_end_request_cur(-EIO);
549 }
550 hd_request();
551 spin_unlock_irq(hd_queue->queue_lock);
552 }
553
do_special_op(struct hd_i_struct * disk,struct request * req)554 static 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, ATA_CMD_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 hd_end_request_cur(-EIO);
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 */
hd_request(void)579 static 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;
587 repeat:
588 del_timer(&device_timer);
589
590 if (!hd_req) {
591 hd_req = blk_fetch_request(hd_queue);
592 if (!hd_req) {
593 do_hd = NULL;
594 return;
595 }
596 }
597 req = hd_req;
598
599 if (reset) {
600 reset_hd();
601 return;
602 }
603 disk = req->rq_disk->private_data;
604 block = blk_rq_pos(req);
605 nsect = blk_rq_sectors(req);
606 if (block >= get_capacity(req->rq_disk) ||
607 ((block+nsect) > get_capacity(req->rq_disk))) {
608 printk("%s: bad access: block=%d, count=%d\n",
609 req->rq_disk->disk_name, block, nsect);
610 hd_end_request_cur(-EIO);
611 goto repeat;
612 }
613
614 if (disk->special_op) {
615 if (do_special_op(disk, req))
616 goto repeat;
617 return;
618 }
619 sec = block % disk->sect + 1;
620 track = block / disk->sect;
621 head = track % disk->head;
622 cyl = track / disk->head;
623 #ifdef DEBUG
624 printk("%s: %sing: CHS=%d/%d/%d, sectors=%d, buffer=%p\n",
625 req->rq_disk->disk_name,
626 req_data_dir(req) == READ ? "read" : "writ",
627 cyl, head, sec, nsect, req->buffer);
628 #endif
629 if (req->cmd_type == REQ_TYPE_FS) {
630 switch (rq_data_dir(req)) {
631 case READ:
632 hd_out(disk, nsect, sec, head, cyl, ATA_CMD_PIO_READ,
633 &read_intr);
634 if (reset)
635 goto repeat;
636 break;
637 case WRITE:
638 hd_out(disk, nsect, sec, head, cyl, ATA_CMD_PIO_WRITE,
639 &write_intr);
640 if (reset)
641 goto repeat;
642 if (wait_DRQ()) {
643 bad_rw_intr();
644 goto repeat;
645 }
646 outsw(HD_DATA, req->buffer, 256);
647 break;
648 default:
649 printk("unknown hd-command\n");
650 hd_end_request_cur(-EIO);
651 break;
652 }
653 }
654 }
655
do_hd_request(struct request_queue * q)656 static void do_hd_request(struct request_queue *q)
657 {
658 hd_request();
659 }
660
hd_getgeo(struct block_device * bdev,struct hd_geometry * geo)661 static int hd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
662 {
663 struct hd_i_struct *disk = bdev->bd_disk->private_data;
664
665 geo->heads = disk->head;
666 geo->sectors = disk->sect;
667 geo->cylinders = disk->cyl;
668 return 0;
669 }
670
671 /*
672 * Releasing a block device means we sync() it, so that it can safely
673 * be forgotten about...
674 */
675
hd_interrupt(int irq,void * dev_id)676 static irqreturn_t hd_interrupt(int irq, void *dev_id)
677 {
678 void (*handler)(void) = do_hd;
679
680 spin_lock(hd_queue->queue_lock);
681
682 do_hd = NULL;
683 del_timer(&device_timer);
684 if (!handler)
685 handler = unexpected_hd_interrupt;
686 handler();
687
688 spin_unlock(hd_queue->queue_lock);
689
690 return IRQ_HANDLED;
691 }
692
693 static const struct block_device_operations hd_fops = {
694 .getgeo = hd_getgeo,
695 };
696
697 /*
698 * This is the hard disk IRQ description. The IRQF_DISABLED in sa_flags
699 * means we run the IRQ-handler with interrupts disabled: this is bad for
700 * interrupt latency, but anything else has led to problems on some
701 * machines.
702 *
703 * We enable interrupts in some of the routines after making sure it's
704 * safe.
705 */
706
hd_init(void)707 static int __init hd_init(void)
708 {
709 int drive;
710
711 if (register_blkdev(HD_MAJOR, "hd"))
712 return -1;
713
714 hd_queue = blk_init_queue(do_hd_request, &hd_lock);
715 if (!hd_queue) {
716 unregister_blkdev(HD_MAJOR, "hd");
717 return -ENOMEM;
718 }
719
720 blk_queue_max_hw_sectors(hd_queue, 255);
721 init_timer(&device_timer);
722 device_timer.function = hd_times_out;
723 blk_queue_logical_block_size(hd_queue, 512);
724
725 if (!NR_HD) {
726 /*
727 * We don't know anything about the drive. This means
728 * that you *MUST* specify the drive parameters to the
729 * kernel yourself.
730 *
731 * If we were on an i386, we used to read this info from
732 * the BIOS or CMOS. This doesn't work all that well,
733 * since this assumes that this is a primary or secondary
734 * drive, and if we're using this legacy driver, it's
735 * probably an auxiliary controller added to recover
736 * legacy data off an ST-506 drive. Either way, it's
737 * definitely safest to have the user explicitly specify
738 * the information.
739 */
740 printk("hd: no drives specified - use hd=cyl,head,sectors"
741 " on kernel command line\n");
742 goto out;
743 }
744
745 for (drive = 0 ; drive < NR_HD ; drive++) {
746 struct gendisk *disk = alloc_disk(64);
747 struct hd_i_struct *p = &hd_info[drive];
748 if (!disk)
749 goto Enomem;
750 disk->major = HD_MAJOR;
751 disk->first_minor = drive << 6;
752 disk->fops = &hd_fops;
753 sprintf(disk->disk_name, "hd%c", 'a'+drive);
754 disk->private_data = p;
755 set_capacity(disk, p->head * p->sect * p->cyl);
756 disk->queue = hd_queue;
757 p->unit = drive;
758 hd_gendisk[drive] = disk;
759 printk("%s: %luMB, CHS=%d/%d/%d\n",
760 disk->disk_name, (unsigned long)get_capacity(disk)/2048,
761 p->cyl, p->head, p->sect);
762 }
763
764 if (request_irq(HD_IRQ, hd_interrupt, IRQF_DISABLED, "hd", NULL)) {
765 printk("hd: unable to get IRQ%d for the hard disk driver\n",
766 HD_IRQ);
767 goto out1;
768 }
769 if (!request_region(HD_DATA, 8, "hd")) {
770 printk(KERN_WARNING "hd: port 0x%x busy\n", HD_DATA);
771 goto out2;
772 }
773 if (!request_region(HD_CMD, 1, "hd(cmd)")) {
774 printk(KERN_WARNING "hd: port 0x%x busy\n", HD_CMD);
775 goto out3;
776 }
777
778 /* Let them fly */
779 for (drive = 0; drive < NR_HD; drive++)
780 add_disk(hd_gendisk[drive]);
781
782 return 0;
783
784 out3:
785 release_region(HD_DATA, 8);
786 out2:
787 free_irq(HD_IRQ, NULL);
788 out1:
789 for (drive = 0; drive < NR_HD; drive++)
790 put_disk(hd_gendisk[drive]);
791 NR_HD = 0;
792 out:
793 del_timer(&device_timer);
794 unregister_blkdev(HD_MAJOR, "hd");
795 blk_cleanup_queue(hd_queue);
796 return -1;
797 Enomem:
798 while (drive--)
799 put_disk(hd_gendisk[drive]);
800 goto out;
801 }
802
parse_hd_setup(char * line)803 static int __init parse_hd_setup(char *line)
804 {
805 int ints[6];
806
807 (void) get_options(line, ARRAY_SIZE(ints), ints);
808 hd_setup(NULL, ints);
809
810 return 1;
811 }
812 __setup("hd=", parse_hd_setup);
813
814 late_initcall(hd_init);
815