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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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070037#include <linux/string.h>
38#include <linux/ioport.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070039#include <linux/init.h>
40#include <linux/blkpg.h>
Bartlomiej Zolnierkiewiczf26b3d72008-10-10 22:39:21 +020041#include <linux/ata.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070042#include <linux/hdreg.h>
43
Bartlomiej Zolnierkiewicz4fe6e302009-04-01 21:42:25 +020044#define HD_IRQ 14
45
Linus Torvalds1da177e2005-04-16 15:20:36 -070046#define REALLY_SLOW_IO
47#include <asm/system.h>
48#include <asm/io.h>
49#include <asm/uaccess.h>
50
51#ifdef __arm__
52#undef HD_IRQ
53#endif
54#include <asm/irq.h>
55#ifdef __arm__
56#define HD_IRQ IRQ_HARDDISK
57#endif
58
59/* Hd controller regster ports */
60
61#define HD_DATA 0x1f0 /* _CTL when writing */
62#define HD_ERROR 0x1f1 /* see err-bits */
63#define HD_NSECTOR 0x1f2 /* nr of sectors to read/write */
64#define HD_SECTOR 0x1f3 /* starting sector */
65#define HD_LCYL 0x1f4 /* starting cylinder */
66#define HD_HCYL 0x1f5 /* high byte of starting cyl */
67#define HD_CURRENT 0x1f6 /* 101dhhhh , d=drive, hhhh=head */
68#define HD_STATUS 0x1f7 /* see status-bits */
69#define HD_FEATURE HD_ERROR /* same io address, read=error, write=feature */
70#define HD_PRECOMP HD_FEATURE /* obsolete use of this port - predates IDE */
71#define HD_COMMAND HD_STATUS /* same io address, read=status, write=cmd */
72
73#define HD_CMD 0x3f6 /* used for resets */
74#define HD_ALTSTATUS 0x3f6 /* same as HD_STATUS but doesn't clear irq */
75
76/* Bits of HD_STATUS */
77#define ERR_STAT 0x01
78#define INDEX_STAT 0x02
79#define ECC_STAT 0x04 /* Corrected error */
80#define DRQ_STAT 0x08
81#define SEEK_STAT 0x10
82#define SERVICE_STAT SEEK_STAT
83#define WRERR_STAT 0x20
84#define READY_STAT 0x40
85#define BUSY_STAT 0x80
86
87/* Bits for HD_ERROR */
88#define MARK_ERR 0x01 /* Bad address mark */
89#define TRK0_ERR 0x02 /* couldn't find track 0 */
90#define ABRT_ERR 0x04 /* Command aborted */
91#define MCR_ERR 0x08 /* media change request */
92#define ID_ERR 0x10 /* ID field not found */
93#define MC_ERR 0x20 /* media changed */
94#define ECC_ERR 0x40 /* Uncorrectable ECC error */
95#define BBD_ERR 0x80 /* pre-EIDE meaning: block marked bad */
96#define ICRC_ERR 0x80 /* new meaning: CRC error during transfer */
97
98static DEFINE_SPINLOCK(hd_lock);
99static struct request_queue *hd_queue;
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900100static struct request *hd_req;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102#define TIMEOUT_VALUE (6*HZ)
103#define HD_DELAY 0
104
105#define MAX_ERRORS 16 /* Max read/write errors/sector */
106#define RESET_FREQ 8 /* Reset controller every 8th retry */
107#define RECAL_FREQ 4 /* Recalibrate every 4th retry */
108#define MAX_HD 2
109
110#define STAT_OK (READY_STAT|SEEK_STAT)
111#define OK_STATUS(s) (((s)&(STAT_OK|(BUSY_STAT|WRERR_STAT|ERR_STAT)))==STAT_OK)
112
113static void recal_intr(void);
114static void bad_rw_intr(void);
115
116static int reset;
117static int hd_error;
118
119/*
120 * This struct defines the HD's and their types.
121 */
122struct hd_i_struct {
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200123 unsigned int head, sect, cyl, wpcom, lzone, ctl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124 int unit;
125 int recalibrate;
126 int special_op;
127};
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200128
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129#ifdef HD_TYPE
130static struct hd_i_struct hd_info[] = { HD_TYPE };
Andi Drebesecea5732007-07-09 23:17:57 +0200131static int NR_HD = ARRAY_SIZE(hd_info);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132#else
133static struct hd_i_struct hd_info[MAX_HD];
134static int NR_HD;
135#endif
136
137static struct gendisk *hd_gendisk[MAX_HD];
138
139static struct timer_list device_timer;
140
141#define TIMEOUT_VALUE (6*HZ)
142
143#define SET_TIMER \
144 do { \
145 mod_timer(&device_timer, jiffies + TIMEOUT_VALUE); \
146 } while (0)
147
148static void (*do_hd)(void) = NULL;
149#define SET_HANDLER(x) \
150if ((do_hd = (x)) != NULL) \
151 SET_TIMER; \
152else \
153 del_timer(&device_timer);
154
155
156#if (HD_DELAY > 0)
Ingo Molnar306e4402005-06-30 02:58:55 -0700157
Ralf Baechle334955e2011-06-01 19:04:57 +0100158#include <linux/i8253.h>
Ingo Molnar306e4402005-06-30 02:58:55 -0700159
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160unsigned long last_req;
161
162unsigned long read_timer(void)
163{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164 unsigned long t, flags;
165 int i;
166
Thomas Gleixnerced918e2010-02-17 16:47:10 +0000167 raw_spin_lock_irqsave(&i8253_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168 t = jiffies * 11932;
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200169 outb_p(0, 0x43);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170 i = inb_p(0x40);
171 i |= inb(0x40) << 8;
Thomas Gleixnerced918e2010-02-17 16:47:10 +0000172 raw_spin_unlock_irqrestore(&i8253_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173 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)
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200184 hdind = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 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
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900194static bool hd_end_request(int err, unsigned int bytes)
195{
196 if (__blk_end_request(hd_req, err, bytes))
197 return true;
198 hd_req = NULL;
199 return false;
200}
201
202static bool hd_end_request_cur(int err)
203{
204 return hd_end_request(err, blk_rq_cur_bytes(hd_req));
205}
206
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200207static void dump_status(const char *msg, unsigned int stat)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208{
209 char *name = "hd?";
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900210 if (hd_req)
211 name = hd_req->rq_disk->disk_name;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212
213#ifdef VERBOSE_ERRORS
214 printk("%s: %s: status=0x%02x { ", name, msg, stat & 0xff);
215 if (stat & BUSY_STAT) printk("Busy ");
216 if (stat & READY_STAT) printk("DriveReady ");
217 if (stat & WRERR_STAT) printk("WriteFault ");
218 if (stat & SEEK_STAT) printk("SeekComplete ");
219 if (stat & DRQ_STAT) printk("DataRequest ");
220 if (stat & ECC_STAT) printk("CorrectedError ");
221 if (stat & INDEX_STAT) printk("Index ");
222 if (stat & ERR_STAT) printk("Error ");
223 printk("}\n");
224 if ((stat & ERR_STAT) == 0) {
225 hd_error = 0;
226 } else {
227 hd_error = inb(HD_ERROR);
228 printk("%s: %s: error=0x%02x { ", name, msg, hd_error & 0xff);
229 if (hd_error & BBD_ERR) printk("BadSector ");
230 if (hd_error & ECC_ERR) printk("UncorrectableError ");
231 if (hd_error & ID_ERR) printk("SectorIdNotFound ");
232 if (hd_error & ABRT_ERR) printk("DriveStatusError ");
233 if (hd_error & TRK0_ERR) printk("TrackZeroNotFound ");
234 if (hd_error & MARK_ERR) printk("AddrMarkNotFound ");
235 printk("}");
236 if (hd_error & (BBD_ERR|ECC_ERR|ID_ERR|MARK_ERR)) {
237 printk(", CHS=%d/%d/%d", (inb(HD_HCYL)<<8) + inb(HD_LCYL),
238 inb(HD_CURRENT) & 0xf, inb(HD_SECTOR));
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900239 if (hd_req)
240 printk(", sector=%ld", blk_rq_pos(hd_req));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 }
242 printk("\n");
243 }
244#else
245 printk("%s: %s: status=0x%02x.\n", name, msg, stat & 0xff);
246 if ((stat & ERR_STAT) == 0) {
247 hd_error = 0;
248 } else {
249 hd_error = inb(HD_ERROR);
250 printk("%s: %s: error=0x%02x.\n", name, msg, hd_error & 0xff);
251 }
252#endif
253}
254
255static void check_status(void)
256{
257 int i = inb_p(HD_STATUS);
258
259 if (!OK_STATUS(i)) {
260 dump_status("check_status", i);
261 bad_rw_intr();
262 }
263}
264
265static int controller_busy(void)
266{
267 int retries = 100000;
268 unsigned char status;
269
270 do {
271 status = inb_p(HD_STATUS);
272 } while ((status & BUSY_STAT) && --retries);
273 return status;
274}
275
276static int status_ok(void)
277{
278 unsigned char status = inb_p(HD_STATUS);
279
280 if (status & BUSY_STAT)
281 return 1; /* Ancient, but does it make sense??? */
282 if (status & WRERR_STAT)
283 return 0;
284 if (!(status & READY_STAT))
285 return 0;
286 if (!(status & SEEK_STAT))
287 return 0;
288 return 1;
289}
290
291static int controller_ready(unsigned int drive, unsigned int head)
292{
293 int retry = 100;
294
295 do {
296 if (controller_busy() & BUSY_STAT)
297 return 0;
298 outb_p(0xA0 | (drive<<4) | head, HD_CURRENT);
299 if (status_ok())
300 return 1;
301 } while (--retry);
302 return 0;
303}
304
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305static void hd_out(struct hd_i_struct *disk,
306 unsigned int nsect,
307 unsigned int sect,
308 unsigned int head,
309 unsigned int cyl,
310 unsigned int cmd,
311 void (*intr_addr)(void))
312{
313 unsigned short port;
314
315#if (HD_DELAY > 0)
316 while (read_timer() - last_req < HD_DELAY)
317 /* nothing */;
318#endif
319 if (reset)
320 return;
321 if (!controller_ready(disk->unit, head)) {
322 reset = 1;
323 return;
324 }
325 SET_HANDLER(intr_addr);
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200326 outb_p(disk->ctl, HD_CMD);
327 port = HD_DATA;
328 outb_p(disk->wpcom >> 2, ++port);
329 outb_p(nsect, ++port);
330 outb_p(sect, ++port);
331 outb_p(cyl, ++port);
332 outb_p(cyl >> 8, ++port);
333 outb_p(0xA0 | (disk->unit << 4) | head, ++port);
334 outb_p(cmd, ++port);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335}
336
337static void hd_request (void);
338
339static int drive_busy(void)
340{
341 unsigned int i;
342 unsigned char c;
343
344 for (i = 0; i < 500000 ; i++) {
345 c = inb_p(HD_STATUS);
346 if ((c & (BUSY_STAT | READY_STAT | SEEK_STAT)) == STAT_OK)
347 return 0;
348 }
349 dump_status("reset timed out", c);
350 return 1;
351}
352
353static void reset_controller(void)
354{
355 int i;
356
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200357 outb_p(4, HD_CMD);
358 for (i = 0; i < 1000; i++) barrier();
359 outb_p(hd_info[0].ctl & 0x0f, HD_CMD);
360 for (i = 0; i < 1000; i++) barrier();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361 if (drive_busy())
362 printk("hd: controller still busy\n");
363 else if ((hd_error = inb(HD_ERROR)) != 1)
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200364 printk("hd: controller reset failed: %02x\n", hd_error);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365}
366
367static void reset_hd(void)
368{
369 static int i;
370
371repeat:
372 if (reset) {
373 reset = 0;
374 i = -1;
375 reset_controller();
376 } else {
377 check_status();
378 if (reset)
379 goto repeat;
380 }
381 if (++i < NR_HD) {
382 struct hd_i_struct *disk = &hd_info[i];
383 disk->special_op = disk->recalibrate = 1;
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200384 hd_out(disk, disk->sect, disk->sect, disk->head-1,
Bartlomiej Zolnierkiewiczf26b3d72008-10-10 22:39:21 +0200385 disk->cyl, ATA_CMD_INIT_DEV_PARAMS, &reset_hd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386 if (reset)
387 goto repeat;
388 } else
389 hd_request();
390}
391
392/*
393 * Ok, don't know what to do with the unexpected interrupts: on some machines
394 * doing a reset and a retry seems to result in an eternal loop. Right now I
395 * ignore it, and just set the timeout.
396 *
397 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever the
398 * drive enters "idle", "standby", or "sleep" mode, so if the status looks
399 * "good", we just ignore the interrupt completely.
400 */
401static void unexpected_hd_interrupt(void)
402{
403 unsigned int stat = inb_p(HD_STATUS);
404
405 if (stat & (BUSY_STAT|DRQ_STAT|ECC_STAT|ERR_STAT)) {
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200406 dump_status("unexpected interrupt", stat);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 SET_TIMER;
408 }
409}
410
411/*
412 * bad_rw_intr() now tries to be a bit smarter and does things
413 * according to the error returned by the controller.
414 * -Mika Liljeberg (liljeber@cs.Helsinki.FI)
415 */
416static void bad_rw_intr(void)
417{
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900418 struct request *req = hd_req;
419
Linus Torvalds1da177e2005-04-16 15:20:36 -0700420 if (req != NULL) {
421 struct hd_i_struct *disk = req->rq_disk->private_data;
422 if (++req->errors >= MAX_ERRORS || (hd_error & BBD_ERR)) {
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900423 hd_end_request_cur(-EIO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424 disk->special_op = disk->recalibrate = 1;
425 } else if (req->errors % RESET_FREQ == 0)
426 reset = 1;
427 else if ((hd_error & TRK0_ERR) || req->errors % RECAL_FREQ == 0)
428 disk->special_op = disk->recalibrate = 1;
429 /* Otherwise just retry */
430 }
431}
432
433static inline int wait_DRQ(void)
434{
Andrew Mortonb0042232008-02-06 02:57:49 +0100435 int retries;
436 int stat;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437
Andrew Mortonb0042232008-02-06 02:57:49 +0100438 for (retries = 0; retries < 100000; retries++) {
439 stat = inb_p(HD_STATUS);
440 if (stat & DRQ_STAT)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441 return 0;
Andrew Mortonb0042232008-02-06 02:57:49 +0100442 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443 dump_status("wait_DRQ", stat);
444 return -1;
445}
446
447static void read_intr(void)
448{
449 struct request *req;
450 int i, retries = 100000;
451
452 do {
453 i = (unsigned) inb_p(HD_STATUS);
454 if (i & BUSY_STAT)
455 continue;
456 if (!OK_STATUS(i))
457 break;
458 if (i & DRQ_STAT)
459 goto ok_to_read;
460 } while (--retries > 0);
461 dump_status("read_intr", i);
462 bad_rw_intr();
463 hd_request();
464 return;
Tejun Heoe091eb62009-04-28 13:06:11 +0900465
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466ok_to_read:
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900467 req = hd_req;
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200468 insw(HD_DATA, req->buffer, 256);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469#ifdef DEBUG
Tejun Heo83096eb2009-05-07 22:24:39 +0900470 printk("%s: read: sector %ld, remaining = %u, buffer=%p\n",
471 req->rq_disk->disk_name, blk_rq_pos(req) + 1,
472 blk_rq_sectors(req) - 1, req->buffer+512);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700473#endif
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900474 if (hd_end_request(0, 512)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475 SET_HANDLER(&read_intr);
476 return;
477 }
Tejun Heoe091eb62009-04-28 13:06:11 +0900478
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479 (void) inb_p(HD_STATUS);
480#if (HD_DELAY > 0)
481 last_req = read_timer();
482#endif
Tejun Heoe091eb62009-04-28 13:06:11 +0900483 hd_request();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484}
485
486static void write_intr(void)
487{
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900488 struct request *req = hd_req;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700489 int i;
490 int retries = 100000;
491
492 do {
493 i = (unsigned) inb_p(HD_STATUS);
494 if (i & BUSY_STAT)
495 continue;
496 if (!OK_STATUS(i))
497 break;
Tejun Heo83096eb2009-05-07 22:24:39 +0900498 if ((blk_rq_sectors(req) <= 1) || (i & DRQ_STAT))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700499 goto ok_to_write;
500 } while (--retries > 0);
501 dump_status("write_intr", i);
502 bad_rw_intr();
503 hd_request();
504 return;
Tejun Heoe091eb62009-04-28 13:06:11 +0900505
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506ok_to_write:
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900507 if (hd_end_request(0, 512)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508 SET_HANDLER(&write_intr);
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200509 outsw(HD_DATA, req->buffer, 256);
Tejun Heoe091eb62009-04-28 13:06:11 +0900510 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700511 }
Tejun Heoe091eb62009-04-28 13:06:11 +0900512
513#if (HD_DELAY > 0)
514 last_req = read_timer();
515#endif
516 hd_request();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517}
518
519static 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 */
532static void hd_times_out(unsigned long dummy)
533{
534 char *name;
535
536 do_hd = NULL;
537
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900538 if (!hd_req)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539 return;
540
Tejun Heoe93b9fb2009-04-28 12:38:33 +0900541 spin_lock_irq(hd_queue->queue_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 reset = 1;
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900543 name = hd_req->rq_disk->disk_name;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544 printk("%s: timeout\n", name);
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900545 if (++hd_req->errors >= MAX_ERRORS) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546#ifdef DEBUG
547 printk("%s: too many errors\n", name);
548#endif
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900549 hd_end_request_cur(-EIO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700550 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551 hd_request();
Tejun Heoe93b9fb2009-04-28 12:38:33 +0900552 spin_unlock_irq(hd_queue->queue_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553}
554
555static int do_special_op(struct hd_i_struct *disk, struct request *req)
556{
557 if (disk->recalibrate) {
558 disk->recalibrate = 0;
Bartlomiej Zolnierkiewiczf26b3d72008-10-10 22:39:21 +0200559 hd_out(disk, disk->sect, 0, 0, 0, ATA_CMD_RESTORE, &recal_intr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 return reset;
561 }
562 if (disk->head > 16) {
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200563 printk("%s: cannot handle device with more than 16 heads - giving up\n", req->rq_disk->disk_name);
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900564 hd_end_request_cur(-EIO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565 }
566 disk->special_op = 0;
567 return 1;
568}
569
570/*
571 * The driver enables interrupts as much as possible. In order to do this,
572 * (a) the device-interrupt is disabled before entering hd_request(),
573 * and (b) the timeout-interrupt is disabled before the sti().
574 *
575 * Interrupts are still masked (by default) whenever we are exchanging
576 * data/cmds with a drive, because some drives seem to have very poor
577 * tolerance for latency during I/O. The IDE driver has support to unmask
578 * interrupts for non-broken hardware, so use that driver if required.
579 */
580static void hd_request(void)
581{
582 unsigned int block, nsect, sec, track, head, cyl;
583 struct hd_i_struct *disk;
584 struct request *req;
585
586 if (do_hd)
587 return;
588repeat:
589 del_timer(&device_timer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900591 if (!hd_req) {
Tejun Heo9934c8c2009-05-08 11:54:16 +0900592 hd_req = blk_fetch_request(hd_queue);
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900593 if (!hd_req) {
594 do_hd = NULL;
595 return;
596 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 }
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900598 req = hd_req;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599
600 if (reset) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601 reset_hd();
602 return;
603 }
604 disk = req->rq_disk->private_data;
Tejun Heo83096eb2009-05-07 22:24:39 +0900605 block = blk_rq_pos(req);
606 nsect = blk_rq_sectors(req);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607 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);
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900611 hd_end_request_cur(-EIO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612 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",
Boaz Harroshe654bc42007-06-20 13:53:23 +0200626 req->rq_disk->disk_name,
627 req_data_dir(req) == READ ? "read" : "writ",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700628 cyl, head, sec, nsect, req->buffer);
629#endif
Christoph Hellwig33659eb2010-08-07 18:17:56 +0200630 if (req->cmd_type == REQ_TYPE_FS) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631 switch (rq_data_dir(req)) {
632 case READ:
Bartlomiej Zolnierkiewiczf26b3d72008-10-10 22:39:21 +0200633 hd_out(disk, nsect, sec, head, cyl, ATA_CMD_PIO_READ,
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200634 &read_intr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635 if (reset)
636 goto repeat;
637 break;
638 case WRITE:
Bartlomiej Zolnierkiewiczf26b3d72008-10-10 22:39:21 +0200639 hd_out(disk, nsect, sec, head, cyl, ATA_CMD_PIO_WRITE,
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200640 &write_intr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641 if (reset)
642 goto repeat;
643 if (wait_DRQ()) {
644 bad_rw_intr();
645 goto repeat;
646 }
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200647 outsw(HD_DATA, req->buffer, 256);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700648 break;
649 default:
650 printk("unknown hd-command\n");
Tejun Heo8a12c4a2009-05-08 11:54:02 +0900651 hd_end_request_cur(-EIO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652 break;
653 }
654 }
655}
656
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200657static void do_hd_request(struct request_queue *q)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700659 hd_request();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660}
661
Christoph Hellwiga885c8c2006-01-08 01:02:50 -0800662static int hd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663{
Christoph Hellwiga885c8c2006-01-08 01:02:50 -0800664 struct hd_i_struct *disk = bdev->bd_disk->private_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665
Christoph Hellwiga885c8c2006-01-08 01:02:50 -0800666 geo->heads = disk->head;
667 geo->sectors = disk->sect;
668 geo->cylinders = disk->cyl;
669 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700670}
671
672/*
673 * Releasing a block device means we sync() it, so that it can safely
674 * be forgotten about...
675 */
676
David Howells7d12e782006-10-05 14:55:46 +0100677static irqreturn_t hd_interrupt(int irq, void *dev_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700678{
679 void (*handler)(void) = do_hd;
680
Tejun Heoe93b9fb2009-04-28 12:38:33 +0900681 spin_lock(hd_queue->queue_lock);
682
Linus Torvalds1da177e2005-04-16 15:20:36 -0700683 do_hd = NULL;
684 del_timer(&device_timer);
685 if (!handler)
686 handler = unexpected_hd_interrupt;
687 handler();
Tejun Heoe93b9fb2009-04-28 12:38:33 +0900688
689 spin_unlock(hd_queue->queue_lock);
690
Linus Torvalds1da177e2005-04-16 15:20:36 -0700691 return IRQ_HANDLED;
692}
693
Alexey Dobriyan83d5cde2009-09-21 17:01:13 -0700694static const struct block_device_operations hd_fops = {
Christoph Hellwiga885c8c2006-01-08 01:02:50 -0800695 .getgeo = hd_getgeo,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696};
697
698/*
Thomas Gleixner362537b2006-07-01 19:29:34 -0700699 * This is the hard disk IRQ description. The IRQF_DISABLED in sa_flags
Linus Torvalds1da177e2005-04-16 15:20:36 -0700700 * means we run the IRQ-handler with interrupts disabled: this is bad for
701 * interrupt latency, but anything else has led to problems on some
702 * machines.
703 *
704 * We enable interrupts in some of the routines after making sure it's
705 * safe.
706 */
707
708static int __init hd_init(void)
709{
710 int drive;
711
Christoph Hellwigddeb9c32009-06-16 22:07:32 +0200712 if (register_blkdev(HD_MAJOR, "hd"))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713 return -1;
714
715 hd_queue = blk_init_queue(do_hd_request, &hd_lock);
716 if (!hd_queue) {
Christoph Hellwigddeb9c32009-06-16 22:07:32 +0200717 unregister_blkdev(HD_MAJOR, "hd");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700718 return -ENOMEM;
719 }
720
Martin K. Petersen086fa5f2010-02-26 00:20:38 -0500721 blk_queue_max_hw_sectors(hd_queue, 255);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722 init_timer(&device_timer);
723 device_timer.function = hd_times_out;
Martin K. Petersene1defc42009-05-22 17:17:49 -0400724 blk_queue_logical_block_size(hd_queue, 512);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726 if (!NR_HD) {
H. Peter Anvin48dd6432007-07-11 12:18:27 -0700727 /*
728 * We don't know anything about the drive. This means
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729 * that you *MUST* specify the drive parameters to the
730 * kernel yourself.
H. Peter Anvin48dd6432007-07-11 12:18:27 -0700731 *
732 * If we were on an i386, we used to read this info from
733 * the BIOS or CMOS. This doesn't work all that well,
734 * since this assumes that this is a primary or secondary
735 * drive, and if we're using this legacy driver, it's
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300736 * probably an auxiliary controller added to recover
H. Peter Anvin48dd6432007-07-11 12:18:27 -0700737 * legacy data off an ST-506 drive. Either way, it's
738 * definitely safest to have the user explicitly specify
739 * the information.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700740 */
741 printk("hd: no drives specified - use hd=cyl,head,sectors"
742 " on kernel command line\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743 goto out;
H. Peter Anvin48dd6432007-07-11 12:18:27 -0700744 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200746 for (drive = 0 ; drive < NR_HD ; drive++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747 struct gendisk *disk = alloc_disk(64);
748 struct hd_i_struct *p = &hd_info[drive];
749 if (!disk)
750 goto Enomem;
Christoph Hellwigddeb9c32009-06-16 22:07:32 +0200751 disk->major = HD_MAJOR;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752 disk->first_minor = drive << 6;
753 disk->fops = &hd_fops;
754 sprintf(disk->disk_name, "hd%c", 'a'+drive);
755 disk->private_data = p;
756 set_capacity(disk, p->head * p->sect * p->cyl);
757 disk->queue = hd_queue;
758 p->unit = drive;
759 hd_gendisk[drive] = disk;
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200760 printk("%s: %luMB, CHS=%d/%d/%d\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761 disk->disk_name, (unsigned long)get_capacity(disk)/2048,
762 p->cyl, p->head, p->sect);
763 }
764
Thomas Gleixner362537b2006-07-01 19:29:34 -0700765 if (request_irq(HD_IRQ, hd_interrupt, IRQF_DISABLED, "hd", NULL)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700766 printk("hd: unable to get IRQ%d for the hard disk driver\n",
767 HD_IRQ);
768 goto out1;
769 }
770 if (!request_region(HD_DATA, 8, "hd")) {
771 printk(KERN_WARNING "hd: port 0x%x busy\n", HD_DATA);
772 goto out2;
773 }
774 if (!request_region(HD_CMD, 1, "hd(cmd)")) {
775 printk(KERN_WARNING "hd: port 0x%x busy\n", HD_CMD);
776 goto out3;
777 }
778
779 /* Let them fly */
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200780 for (drive = 0; drive < NR_HD; drive++)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781 add_disk(hd_gendisk[drive]);
782
783 return 0;
784
785out3:
786 release_region(HD_DATA, 8);
787out2:
788 free_irq(HD_IRQ, NULL);
789out1:
790 for (drive = 0; drive < NR_HD; drive++)
791 put_disk(hd_gendisk[drive]);
792 NR_HD = 0;
793out:
794 del_timer(&device_timer);
Christoph Hellwigddeb9c32009-06-16 22:07:32 +0200795 unregister_blkdev(HD_MAJOR, "hd");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796 blk_cleanup_queue(hd_queue);
797 return -1;
798Enomem:
799 while (drive--)
800 put_disk(hd_gendisk[drive]);
801 goto out;
802}
803
Paolo Ciarrocchiec297822008-04-26 17:36:41 +0200804static int __init parse_hd_setup(char *line)
805{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806 int ints[6];
807
808 (void) get_options(line, ARRAY_SIZE(ints), ints);
809 hd_setup(NULL, ints);
810
811 return 1;
812}
813__setup("hd=", parse_hd_setup);
814
Adrian Bunk01c22bf2008-07-16 20:33:47 +0200815late_initcall(hd_init);