Commit | Line | Data |
---|---|---|
1da177e4 LT |
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> | |
1da177e4 LT |
40 | #include <linux/init.h> |
41 | #include <linux/blkpg.h> | |
42 | #include <linux/hdreg.h> | |
43 | ||
44 | #define REALLY_SLOW_IO | |
45 | #include <asm/system.h> | |
46 | #include <asm/io.h> | |
47 | #include <asm/uaccess.h> | |
48 | ||
49 | #ifdef __arm__ | |
50 | #undef HD_IRQ | |
51 | #endif | |
52 | #include <asm/irq.h> | |
53 | #ifdef __arm__ | |
54 | #define HD_IRQ IRQ_HARDDISK | |
55 | #endif | |
56 | ||
57 | /* Hd controller regster ports */ | |
58 | ||
59 | #define HD_DATA 0x1f0 /* _CTL when writing */ | |
60 | #define HD_ERROR 0x1f1 /* see err-bits */ | |
61 | #define HD_NSECTOR 0x1f2 /* nr of sectors to read/write */ | |
62 | #define HD_SECTOR 0x1f3 /* starting sector */ | |
63 | #define HD_LCYL 0x1f4 /* starting cylinder */ | |
64 | #define HD_HCYL 0x1f5 /* high byte of starting cyl */ | |
65 | #define HD_CURRENT 0x1f6 /* 101dhhhh , d=drive, hhhh=head */ | |
66 | #define HD_STATUS 0x1f7 /* see status-bits */ | |
67 | #define HD_FEATURE HD_ERROR /* same io address, read=error, write=feature */ | |
68 | #define HD_PRECOMP HD_FEATURE /* obsolete use of this port - predates IDE */ | |
69 | #define HD_COMMAND HD_STATUS /* same io address, read=status, write=cmd */ | |
70 | ||
71 | #define HD_CMD 0x3f6 /* used for resets */ | |
72 | #define HD_ALTSTATUS 0x3f6 /* same as HD_STATUS but doesn't clear irq */ | |
73 | ||
74 | /* Bits of HD_STATUS */ | |
75 | #define ERR_STAT 0x01 | |
76 | #define INDEX_STAT 0x02 | |
77 | #define ECC_STAT 0x04 /* Corrected error */ | |
78 | #define DRQ_STAT 0x08 | |
79 | #define SEEK_STAT 0x10 | |
80 | #define SERVICE_STAT SEEK_STAT | |
81 | #define WRERR_STAT 0x20 | |
82 | #define READY_STAT 0x40 | |
83 | #define BUSY_STAT 0x80 | |
84 | ||
85 | /* Bits for HD_ERROR */ | |
86 | #define MARK_ERR 0x01 /* Bad address mark */ | |
87 | #define TRK0_ERR 0x02 /* couldn't find track 0 */ | |
88 | #define ABRT_ERR 0x04 /* Command aborted */ | |
89 | #define MCR_ERR 0x08 /* media change request */ | |
90 | #define ID_ERR 0x10 /* ID field not found */ | |
91 | #define MC_ERR 0x20 /* media changed */ | |
92 | #define ECC_ERR 0x40 /* Uncorrectable ECC error */ | |
93 | #define BBD_ERR 0x80 /* pre-EIDE meaning: block marked bad */ | |
94 | #define ICRC_ERR 0x80 /* new meaning: CRC error during transfer */ | |
95 | ||
96 | static DEFINE_SPINLOCK(hd_lock); | |
97 | static struct request_queue *hd_queue; | |
98 | ||
99 | #define MAJOR_NR HD_MAJOR | |
100 | #define QUEUE (hd_queue) | |
101 | #define CURRENT elv_next_request(hd_queue) | |
102 | ||
103 | #define TIMEOUT_VALUE (6*HZ) | |
104 | #define HD_DELAY 0 | |
105 | ||
106 | #define MAX_ERRORS 16 /* Max read/write errors/sector */ | |
107 | #define RESET_FREQ 8 /* Reset controller every 8th retry */ | |
108 | #define RECAL_FREQ 4 /* Recalibrate every 4th retry */ | |
109 | #define MAX_HD 2 | |
110 | ||
111 | #define STAT_OK (READY_STAT|SEEK_STAT) | |
112 | #define OK_STATUS(s) (((s)&(STAT_OK|(BUSY_STAT|WRERR_STAT|ERR_STAT)))==STAT_OK) | |
113 | ||
114 | static void recal_intr(void); | |
115 | static void bad_rw_intr(void); | |
116 | ||
117 | static int reset; | |
118 | static int hd_error; | |
119 | ||
120 | /* | |
121 | * This struct defines the HD's and their types. | |
122 | */ | |
123 | struct hd_i_struct { | |
ec29782b | 124 | unsigned int head, sect, cyl, wpcom, lzone, ctl; |
1da177e4 LT |
125 | int unit; |
126 | int recalibrate; | |
127 | int special_op; | |
128 | }; | |
ec29782b | 129 | |
1da177e4 LT |
130 | #ifdef HD_TYPE |
131 | static struct hd_i_struct hd_info[] = { HD_TYPE }; | |
ecea5730 | 132 | static int NR_HD = ARRAY_SIZE(hd_info); |
1da177e4 LT |
133 | #else |
134 | static struct hd_i_struct hd_info[MAX_HD]; | |
135 | static int NR_HD; | |
136 | #endif | |
137 | ||
138 | static struct gendisk *hd_gendisk[MAX_HD]; | |
139 | ||
140 | static struct timer_list device_timer; | |
141 | ||
142 | #define TIMEOUT_VALUE (6*HZ) | |
143 | ||
144 | #define SET_TIMER \ | |
145 | do { \ | |
146 | mod_timer(&device_timer, jiffies + TIMEOUT_VALUE); \ | |
147 | } while (0) | |
148 | ||
149 | static void (*do_hd)(void) = NULL; | |
150 | #define SET_HANDLER(x) \ | |
151 | if ((do_hd = (x)) != NULL) \ | |
152 | SET_TIMER; \ | |
153 | else \ | |
154 | del_timer(&device_timer); | |
155 | ||
156 | ||
157 | #if (HD_DELAY > 0) | |
306e440d IM |
158 | |
159 | #include <asm/i8253.h> | |
160 | ||
1da177e4 LT |
161 | unsigned long last_req; |
162 | ||
163 | unsigned long read_timer(void) | |
164 | { | |
1da177e4 LT |
165 | unsigned long t, flags; |
166 | int i; | |
167 | ||
168 | spin_lock_irqsave(&i8253_lock, flags); | |
169 | t = jiffies * 11932; | |
ec29782b | 170 | outb_p(0, 0x43); |
1da177e4 LT |
171 | i = inb_p(0x40); |
172 | i |= inb(0x40) << 8; | |
173 | spin_unlock_irqrestore(&i8253_lock, flags); | |
174 | return(t - i); | |
175 | } | |
176 | #endif | |
177 | ||
178 | static void __init hd_setup(char *str, int *ints) | |
179 | { | |
180 | int hdind = 0; | |
181 | ||
182 | if (ints[0] != 3) | |
183 | return; | |
184 | if (hd_info[0].head != 0) | |
ec29782b | 185 | hdind = 1; |
1da177e4 LT |
186 | hd_info[hdind].head = ints[2]; |
187 | hd_info[hdind].sect = ints[3]; | |
188 | hd_info[hdind].cyl = ints[1]; | |
189 | hd_info[hdind].wpcom = 0; | |
190 | hd_info[hdind].lzone = ints[1]; | |
191 | hd_info[hdind].ctl = (ints[2] > 8 ? 8 : 0); | |
192 | NR_HD = hdind+1; | |
193 | } | |
194 | ||
ec29782b | 195 | static void dump_status(const char *msg, unsigned int stat) |
1da177e4 LT |
196 | { |
197 | char *name = "hd?"; | |
198 | if (CURRENT) | |
199 | name = CURRENT->rq_disk->disk_name; | |
200 | ||
201 | #ifdef VERBOSE_ERRORS | |
202 | printk("%s: %s: status=0x%02x { ", name, msg, stat & 0xff); | |
203 | if (stat & BUSY_STAT) printk("Busy "); | |
204 | if (stat & READY_STAT) printk("DriveReady "); | |
205 | if (stat & WRERR_STAT) printk("WriteFault "); | |
206 | if (stat & SEEK_STAT) printk("SeekComplete "); | |
207 | if (stat & DRQ_STAT) printk("DataRequest "); | |
208 | if (stat & ECC_STAT) printk("CorrectedError "); | |
209 | if (stat & INDEX_STAT) printk("Index "); | |
210 | if (stat & ERR_STAT) printk("Error "); | |
211 | printk("}\n"); | |
212 | if ((stat & ERR_STAT) == 0) { | |
213 | hd_error = 0; | |
214 | } else { | |
215 | hd_error = inb(HD_ERROR); | |
216 | printk("%s: %s: error=0x%02x { ", name, msg, hd_error & 0xff); | |
217 | if (hd_error & BBD_ERR) printk("BadSector "); | |
218 | if (hd_error & ECC_ERR) printk("UncorrectableError "); | |
219 | if (hd_error & ID_ERR) printk("SectorIdNotFound "); | |
220 | if (hd_error & ABRT_ERR) printk("DriveStatusError "); | |
221 | if (hd_error & TRK0_ERR) printk("TrackZeroNotFound "); | |
222 | if (hd_error & MARK_ERR) printk("AddrMarkNotFound "); | |
223 | printk("}"); | |
224 | if (hd_error & (BBD_ERR|ECC_ERR|ID_ERR|MARK_ERR)) { | |
225 | printk(", CHS=%d/%d/%d", (inb(HD_HCYL)<<8) + inb(HD_LCYL), | |
226 | inb(HD_CURRENT) & 0xf, inb(HD_SECTOR)); | |
227 | if (CURRENT) | |
228 | printk(", sector=%ld", CURRENT->sector); | |
229 | } | |
230 | printk("\n"); | |
231 | } | |
232 | #else | |
233 | printk("%s: %s: status=0x%02x.\n", name, msg, stat & 0xff); | |
234 | if ((stat & ERR_STAT) == 0) { | |
235 | hd_error = 0; | |
236 | } else { | |
237 | hd_error = inb(HD_ERROR); | |
238 | printk("%s: %s: error=0x%02x.\n", name, msg, hd_error & 0xff); | |
239 | } | |
240 | #endif | |
241 | } | |
242 | ||
243 | static void check_status(void) | |
244 | { | |
245 | int i = inb_p(HD_STATUS); | |
246 | ||
247 | if (!OK_STATUS(i)) { | |
248 | dump_status("check_status", i); | |
249 | bad_rw_intr(); | |
250 | } | |
251 | } | |
252 | ||
253 | static int controller_busy(void) | |
254 | { | |
255 | int retries = 100000; | |
256 | unsigned char status; | |
257 | ||
258 | do { | |
259 | status = inb_p(HD_STATUS); | |
260 | } while ((status & BUSY_STAT) && --retries); | |
261 | return status; | |
262 | } | |
263 | ||
264 | static int status_ok(void) | |
265 | { | |
266 | unsigned char status = inb_p(HD_STATUS); | |
267 | ||
268 | if (status & BUSY_STAT) | |
269 | return 1; /* Ancient, but does it make sense??? */ | |
270 | if (status & WRERR_STAT) | |
271 | return 0; | |
272 | if (!(status & READY_STAT)) | |
273 | return 0; | |
274 | if (!(status & SEEK_STAT)) | |
275 | return 0; | |
276 | return 1; | |
277 | } | |
278 | ||
279 | static int controller_ready(unsigned int drive, unsigned int head) | |
280 | { | |
281 | int retry = 100; | |
282 | ||
283 | do { | |
284 | if (controller_busy() & BUSY_STAT) | |
285 | return 0; | |
286 | outb_p(0xA0 | (drive<<4) | head, HD_CURRENT); | |
287 | if (status_ok()) | |
288 | return 1; | |
289 | } while (--retry); | |
290 | return 0; | |
291 | } | |
292 | ||
1da177e4 LT |
293 | static 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); | |
ec29782b PC |
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); | |
1da177e4 LT |
323 | } |
324 | ||
325 | static void hd_request (void); | |
326 | ||
327 | static 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 | ||
341 | static void reset_controller(void) | |
342 | { | |
343 | int i; | |
344 | ||
ec29782b PC |
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(); | |
1da177e4 LT |
349 | if (drive_busy()) |
350 | printk("hd: controller still busy\n"); | |
351 | else if ((hd_error = inb(HD_ERROR)) != 1) | |
ec29782b | 352 | printk("hd: controller reset failed: %02x\n", hd_error); |
1da177e4 LT |
353 | } |
354 | ||
355 | static void reset_hd(void) | |
356 | { | |
357 | static int i; | |
358 | ||
359 | repeat: | |
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; | |
ec29782b PC |
372 | hd_out(disk, disk->sect, disk->sect, disk->head-1, |
373 | disk->cyl, WIN_SPECIFY, &reset_hd); | |
1da177e4 LT |
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 | */ | |
389 | static 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)) { | |
ec29782b | 394 | dump_status("unexpected interrupt", stat); |
1da177e4 LT |
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 | */ | |
404 | static 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 | ||
420 | static inline int wait_DRQ(void) | |
421 | { | |
b004223d AM |
422 | int retries; |
423 | int stat; | |
1da177e4 | 424 | |
b004223d AM |
425 | for (retries = 0; retries < 100000; retries++) { |
426 | stat = inb_p(HD_STATUS); | |
427 | if (stat & DRQ_STAT) | |
1da177e4 | 428 | return 0; |
b004223d | 429 | } |
1da177e4 LT |
430 | dump_status("wait_DRQ", stat); |
431 | return -1; | |
432 | } | |
433 | ||
434 | static void read_intr(void) | |
435 | { | |
436 | struct request *req; | |
437 | int i, retries = 100000; | |
438 | ||
439 | do { | |
440 | i = (unsigned) inb_p(HD_STATUS); | |
441 | if (i & BUSY_STAT) | |
442 | continue; | |
443 | if (!OK_STATUS(i)) | |
444 | break; | |
445 | if (i & DRQ_STAT) | |
446 | goto ok_to_read; | |
447 | } while (--retries > 0); | |
448 | dump_status("read_intr", i); | |
449 | bad_rw_intr(); | |
450 | hd_request(); | |
451 | return; | |
452 | ok_to_read: | |
453 | req = CURRENT; | |
ec29782b | 454 | insw(HD_DATA, req->buffer, 256); |
1da177e4 LT |
455 | req->sector++; |
456 | req->buffer += 512; | |
457 | req->errors = 0; | |
458 | i = --req->nr_sectors; | |
459 | --req->current_nr_sectors; | |
460 | #ifdef DEBUG | |
461 | printk("%s: read: sector %ld, remaining = %ld, buffer=%p\n", | |
462 | req->rq_disk->disk_name, req->sector, req->nr_sectors, | |
6a34b57b | 463 | req->buffer+512); |
1da177e4 LT |
464 | #endif |
465 | if (req->current_nr_sectors <= 0) | |
466 | end_request(req, 1); | |
467 | if (i > 0) { | |
468 | SET_HANDLER(&read_intr); | |
469 | return; | |
470 | } | |
471 | (void) inb_p(HD_STATUS); | |
472 | #if (HD_DELAY > 0) | |
473 | last_req = read_timer(); | |
474 | #endif | |
475 | if (elv_next_request(QUEUE)) | |
476 | hd_request(); | |
477 | return; | |
478 | } | |
479 | ||
480 | static void write_intr(void) | |
481 | { | |
482 | struct request *req = CURRENT; | |
483 | int i; | |
484 | int retries = 100000; | |
485 | ||
486 | do { | |
487 | i = (unsigned) inb_p(HD_STATUS); | |
488 | if (i & BUSY_STAT) | |
489 | continue; | |
490 | if (!OK_STATUS(i)) | |
491 | break; | |
492 | if ((req->nr_sectors <= 1) || (i & DRQ_STAT)) | |
493 | goto ok_to_write; | |
494 | } while (--retries > 0); | |
495 | dump_status("write_intr", i); | |
496 | bad_rw_intr(); | |
497 | hd_request(); | |
498 | return; | |
499 | ok_to_write: | |
500 | req->sector++; | |
501 | i = --req->nr_sectors; | |
502 | --req->current_nr_sectors; | |
503 | req->buffer += 512; | |
504 | if (!i || (req->bio && req->current_nr_sectors <= 0)) | |
505 | end_request(req, 1); | |
506 | if (i > 0) { | |
507 | SET_HANDLER(&write_intr); | |
ec29782b | 508 | outsw(HD_DATA, req->buffer, 256); |
1da177e4 LT |
509 | local_irq_enable(); |
510 | } else { | |
511 | #if (HD_DELAY > 0) | |
512 | last_req = read_timer(); | |
513 | #endif | |
514 | hd_request(); | |
515 | } | |
516 | return; | |
517 | } | |
518 | ||
519 | static void recal_intr(void) | |
520 | { | |
521 | check_status(); | |
522 | #if (HD_DELAY > 0) | |
523 | last_req = read_timer(); | |
524 | #endif | |
525 | hd_request(); | |
526 | } | |
527 | ||
528 | /* | |
529 | * This is another of the error-routines I don't know what to do with. The | |
530 | * best idea seems to just set reset, and start all over again. | |
531 | */ | |
532 | static void hd_times_out(unsigned long dummy) | |
533 | { | |
534 | char *name; | |
535 | ||
536 | do_hd = NULL; | |
537 | ||
538 | if (!CURRENT) | |
539 | return; | |
540 | ||
541 | disable_irq(HD_IRQ); | |
542 | local_irq_enable(); | |
543 | reset = 1; | |
544 | name = CURRENT->rq_disk->disk_name; | |
545 | printk("%s: timeout\n", name); | |
546 | if (++CURRENT->errors >= MAX_ERRORS) { | |
547 | #ifdef DEBUG | |
548 | printk("%s: too many errors\n", name); | |
549 | #endif | |
550 | end_request(CURRENT, 0); | |
551 | } | |
552 | local_irq_disable(); | |
553 | hd_request(); | |
554 | enable_irq(HD_IRQ); | |
555 | } | |
556 | ||
557 | static int do_special_op(struct hd_i_struct *disk, struct request *req) | |
558 | { | |
559 | if (disk->recalibrate) { | |
560 | disk->recalibrate = 0; | |
ec29782b | 561 | hd_out(disk, disk->sect, 0, 0, 0, WIN_RESTORE, &recal_intr); |
1da177e4 LT |
562 | return reset; |
563 | } | |
564 | if (disk->head > 16) { | |
ec29782b | 565 | printk("%s: cannot handle device with more than 16 heads - giving up\n", req->rq_disk->disk_name); |
1da177e4 LT |
566 | end_request(req, 0); |
567 | } | |
568 | disk->special_op = 0; | |
569 | return 1; | |
570 | } | |
571 | ||
572 | /* | |
573 | * The driver enables interrupts as much as possible. In order to do this, | |
574 | * (a) the device-interrupt is disabled before entering hd_request(), | |
575 | * and (b) the timeout-interrupt is disabled before the sti(). | |
576 | * | |
577 | * Interrupts are still masked (by default) whenever we are exchanging | |
578 | * data/cmds with a drive, because some drives seem to have very poor | |
579 | * tolerance for latency during I/O. The IDE driver has support to unmask | |
580 | * interrupts for non-broken hardware, so use that driver if required. | |
581 | */ | |
582 | static void hd_request(void) | |
583 | { | |
584 | unsigned int block, nsect, sec, track, head, cyl; | |
585 | struct hd_i_struct *disk; | |
586 | struct request *req; | |
587 | ||
588 | if (do_hd) | |
589 | return; | |
590 | repeat: | |
591 | del_timer(&device_timer); | |
592 | local_irq_enable(); | |
593 | ||
594 | req = CURRENT; | |
595 | if (!req) { | |
596 | do_hd = NULL; | |
597 | return; | |
598 | } | |
599 | ||
600 | if (reset) { | |
601 | local_irq_disable(); | |
602 | reset_hd(); | |
603 | return; | |
604 | } | |
605 | disk = req->rq_disk->private_data; | |
606 | block = req->sector; | |
607 | nsect = req->nr_sectors; | |
608 | if (block >= get_capacity(req->rq_disk) || | |
609 | ((block+nsect) > get_capacity(req->rq_disk))) { | |
610 | printk("%s: bad access: block=%d, count=%d\n", | |
611 | req->rq_disk->disk_name, block, nsect); | |
612 | end_request(req, 0); | |
613 | goto repeat; | |
614 | } | |
615 | ||
616 | if (disk->special_op) { | |
617 | if (do_special_op(disk, req)) | |
618 | goto repeat; | |
619 | return; | |
620 | } | |
621 | sec = block % disk->sect + 1; | |
622 | track = block / disk->sect; | |
623 | head = track % disk->head; | |
624 | cyl = track / disk->head; | |
625 | #ifdef DEBUG | |
626 | printk("%s: %sing: CHS=%d/%d/%d, sectors=%d, buffer=%p\n", | |
e654bc43 BH |
627 | req->rq_disk->disk_name, |
628 | req_data_dir(req) == READ ? "read" : "writ", | |
1da177e4 LT |
629 | cyl, head, sec, nsect, req->buffer); |
630 | #endif | |
4aff5e23 | 631 | if (blk_fs_request(req)) { |
1da177e4 LT |
632 | switch (rq_data_dir(req)) { |
633 | case READ: | |
ec29782b PC |
634 | hd_out(disk, nsect, sec, head, cyl, WIN_READ, |
635 | &read_intr); | |
1da177e4 LT |
636 | if (reset) |
637 | goto repeat; | |
638 | break; | |
639 | case WRITE: | |
ec29782b PC |
640 | hd_out(disk, nsect, sec, head, cyl, WIN_WRITE, |
641 | &write_intr); | |
1da177e4 LT |
642 | if (reset) |
643 | goto repeat; | |
644 | if (wait_DRQ()) { | |
645 | bad_rw_intr(); | |
646 | goto repeat; | |
647 | } | |
ec29782b | 648 | outsw(HD_DATA, req->buffer, 256); |
1da177e4 LT |
649 | break; |
650 | default: | |
651 | printk("unknown hd-command\n"); | |
652 | end_request(req, 0); | |
653 | break; | |
654 | } | |
655 | } | |
656 | } | |
657 | ||
ec29782b | 658 | static void do_hd_request(struct request_queue *q) |
1da177e4 LT |
659 | { |
660 | disable_irq(HD_IRQ); | |
661 | hd_request(); | |
662 | enable_irq(HD_IRQ); | |
663 | } | |
664 | ||
a885c8c4 | 665 | static int hd_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
1da177e4 | 666 | { |
a885c8c4 CH |
667 | struct hd_i_struct *disk = bdev->bd_disk->private_data; |
668 | ||
669 | geo->heads = disk->head; | |
670 | geo->sectors = disk->sect; | |
671 | geo->cylinders = disk->cyl; | |
672 | return 0; | |
1da177e4 LT |
673 | } |
674 | ||
675 | /* | |
676 | * Releasing a block device means we sync() it, so that it can safely | |
677 | * be forgotten about... | |
678 | */ | |
679 | ||
7d12e780 | 680 | static irqreturn_t hd_interrupt(int irq, void *dev_id) |
1da177e4 LT |
681 | { |
682 | void (*handler)(void) = do_hd; | |
683 | ||
684 | do_hd = NULL; | |
685 | del_timer(&device_timer); | |
686 | if (!handler) | |
687 | handler = unexpected_hd_interrupt; | |
688 | handler(); | |
689 | local_irq_enable(); | |
690 | return IRQ_HANDLED; | |
691 | } | |
692 | ||
693 | static struct block_device_operations hd_fops = { | |
a885c8c4 | 694 | .getgeo = hd_getgeo, |
1da177e4 LT |
695 | }; |
696 | ||
697 | /* | |
362537b9 | 698 | * This is the hard disk IRQ description. The IRQF_DISABLED in sa_flags |
1da177e4 LT |
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 | ||
707 | static int __init hd_init(void) | |
708 | { | |
709 | int drive; | |
710 | ||
ec29782b | 711 | if (register_blkdev(MAJOR_NR, "hd")) |
1da177e4 LT |
712 | return -1; |
713 | ||
714 | hd_queue = blk_init_queue(do_hd_request, &hd_lock); | |
715 | if (!hd_queue) { | |
ec29782b | 716 | unregister_blkdev(MAJOR_NR, "hd"); |
1da177e4 LT |
717 | return -ENOMEM; |
718 | } | |
719 | ||
720 | blk_queue_max_sectors(hd_queue, 255); | |
721 | init_timer(&device_timer); | |
722 | device_timer.function = hd_times_out; | |
723 | blk_queue_hardsect_size(hd_queue, 512); | |
724 | ||
1da177e4 | 725 | if (!NR_HD) { |
48dd643c PA |
726 | /* |
727 | * We don't know anything about the drive. This means | |
1da177e4 LT |
728 | * that you *MUST* specify the drive parameters to the |
729 | * kernel yourself. | |
48dd643c PA |
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 auxilliary 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. | |
1da177e4 LT |
739 | */ |
740 | printk("hd: no drives specified - use hd=cyl,head,sectors" | |
741 | " on kernel command line\n"); | |
1da177e4 | 742 | goto out; |
48dd643c | 743 | } |
1da177e4 | 744 | |
ec29782b | 745 | for (drive = 0 ; drive < NR_HD ; drive++) { |
1da177e4 LT |
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 = MAJOR_NR; | |
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; | |
ec29782b | 759 | printk("%s: %luMB, CHS=%d/%d/%d\n", |
1da177e4 LT |
760 | disk->disk_name, (unsigned long)get_capacity(disk)/2048, |
761 | p->cyl, p->head, p->sect); | |
762 | } | |
763 | ||
362537b9 | 764 | if (request_irq(HD_IRQ, hd_interrupt, IRQF_DISABLED, "hd", NULL)) { |
1da177e4 LT |
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 */ | |
ec29782b | 779 | for (drive = 0; drive < NR_HD; drive++) |
1da177e4 LT |
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); | |
ec29782b | 794 | unregister_blkdev(MAJOR_NR, "hd"); |
1da177e4 LT |
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 | ||
ec29782b PC |
803 | static int __init parse_hd_setup(char *line) |
804 | { | |
1da177e4 LT |
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 | ||
01c22bfc | 814 | late_initcall(hd_init); |