source: mainline/uspace/srv/bd/ata_bd/ata_bd.c@ 197ef43

lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since 197ef43 was 47b7006, checked in by Martin Decky <martin@…>, 15 years ago

improve run-time termination

  • get rid of exit()
  • get rid of _exit(), use the common exit()
  • get rid of core(), use the common abort()
  • make main() more fail-safe (call abort() on unhealthy conditions), call async_sess_init() explicitly
  • add several libc-private headers for cleaner environment
  • use SYS_TASK_EXIT in exit() and abort()
  • Property mode set to 100644
File size: 18.3 KB
Line 
1/*
2 * Copyright (c) 2009 Jiri Svoboda
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * - Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * - The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29/** @addtogroup bd
30 * @{
31 */
32
33/**
34 * @file
35 * @brief ATA disk driver
36 *
37 * This driver supports CHS, 28-bit and 48-bit LBA addressing. It only uses
38 * PIO transfers. There is no support DMA, the PACKET feature set or any other
39 * fancy features such as S.M.A.R.T, removable devices, etc.
40 *
41 * This driver is based on the ATA-1, ATA-2, ATA-3 and ATA/ATAPI-4 through 7
42 * standards, as published by the ANSI, NCITS and INCITS standards bodies,
43 * which are freely available. This driver contains no vendor-specific
44 * code at this moment.
45 *
46 * The driver services a single controller which can have up to two disks
47 * attached.
48 */
49
50#include <stdio.h>
51#include <libarch/ddi.h>
52#include <ddi.h>
53#include <ipc/bd.h>
54#include <async.h>
55#include <as.h>
56#include <fibril_synch.h>
57#include <str.h>
58#include <devmap.h>
59#include <sys/types.h>
60#include <inttypes.h>
61#include <errno.h>
62#include <bool.h>
63#include <task.h>
64#include <macros.h>
65
66#include "ata_hw.h"
67#include "ata_bd.h"
68
69#define NAME "ata_bd"
70#define NAMESPACE "bd"
71
72/** Number of defined legacy controller base addresses. */
73#define LEGACY_CTLS 4
74
75/** Physical block size. Should be always 512. */
76static const size_t block_size = 512;
77
78/** Size of the communication area. */
79static size_t comm_size;
80
81/** I/O base address of the command registers. */
82static uintptr_t cmd_physical;
83/** I/O base address of the control registers. */
84static uintptr_t ctl_physical;
85
86/** I/O base addresses for legacy (ISA-compatible) controllers. */
87static ata_base_t legacy_base[LEGACY_CTLS] = {
88 { 0x1f0, 0x3f0 },
89 { 0x170, 0x370 },
90 { 0x1e8, 0x3e8 },
91 { 0x168, 0x368 }
92};
93
94static ata_cmd_t *cmd;
95static ata_ctl_t *ctl;
96
97/** Per-disk state. */
98static disk_t disk[MAX_DISKS];
99
100static void print_syntax(void);
101static int ata_bd_init(void);
102static void ata_bd_connection(ipc_callid_t iid, ipc_call_t *icall);
103static int ata_bd_read_blocks(int disk_id, uint64_t ba, size_t cnt,
104 void *buf);
105static int ata_bd_write_blocks(int disk_id, uint64_t ba, size_t cnt,
106 const void *buf);
107static int ata_bd_read_block(int disk_id, uint64_t ba, size_t cnt,
108 void *buf);
109static int ata_bd_write_block(int disk_id, uint64_t ba, size_t cnt,
110 const void *buf);
111static int disk_init(disk_t *d, int disk_id);
112static int drive_identify(int drive_id, void *buf);
113static void disk_print_summary(disk_t *d);
114static int coord_calc(disk_t *d, uint64_t ba, block_coord_t *bc);
115static void coord_sc_program(const block_coord_t *bc, uint16_t scnt);
116static int wait_status(unsigned set, unsigned n_reset, uint8_t *pstatus,
117 unsigned timeout);
118
119int main(int argc, char **argv)
120{
121 char name[16];
122 int i, rc;
123 int n_disks;
124 unsigned ctl_num;
125 char *eptr;
126
127 printf(NAME ": ATA disk driver\n");
128
129 if (argc > 1) {
130 ctl_num = strtoul(argv[1], &eptr, 0);
131 if (*eptr != '\0' || ctl_num == 0 || ctl_num > 4) {
132 printf("Invalid argument.\n");
133 print_syntax();
134 return -1;
135 }
136 } else {
137 ctl_num = 1;
138 }
139
140 cmd_physical = legacy_base[ctl_num - 1].cmd;
141 ctl_physical = legacy_base[ctl_num - 1].ctl;
142
143 printf("I/O address %p/%p\n", (void *) cmd_physical,
144 (void *) ctl_physical);
145
146 if (ata_bd_init() != EOK)
147 return -1;
148
149 for (i = 0; i < MAX_DISKS; i++) {
150 printf("Identify drive %d... ", i);
151 fflush(stdout);
152
153 rc = disk_init(&disk[i], i);
154
155 if (rc == EOK) {
156 disk_print_summary(&disk[i]);
157 } else {
158 printf("Not found.\n");
159 }
160 }
161
162 n_disks = 0;
163
164 for (i = 0; i < MAX_DISKS; i++) {
165 /* Skip unattached drives. */
166 if (disk[i].present == false)
167 continue;
168
169 snprintf(name, 16, "%s/ata%udisk%d", NAMESPACE, ctl_num, i);
170 rc = devmap_device_register(name, &disk[i].devmap_handle);
171 if (rc != EOK) {
172 printf(NAME ": Unable to register device %s.\n", name);
173 return rc;
174 }
175 ++n_disks;
176 }
177
178 if (n_disks == 0) {
179 printf("No disks detected.\n");
180 return -1;
181 }
182
183 printf(NAME ": Accepting connections\n");
184 task_retval(0);
185 async_manager();
186
187 /* Not reached */
188 return 0;
189}
190
191
192static void print_syntax(void)
193{
194 printf("Syntax: " NAME " <controller_number>\n");
195 printf("Controller number = 1..4\n");
196}
197
198/** Print one-line device summary. */
199static void disk_print_summary(disk_t *d)
200{
201 uint64_t mbytes;
202
203 printf("%s: ", d->model);
204
205 switch (d->amode) {
206 case am_chs:
207 printf("CHS %u cylinders, %u heads, %u sectors",
208 disk->geom.cylinders, disk->geom.heads, disk->geom.sectors);
209 break;
210 case am_lba28:
211 printf("LBA-28");
212 break;
213 case am_lba48:
214 printf("LBA-48");
215 break;
216 }
217
218 printf(" %" PRIu64 " blocks", d->blocks);
219
220 mbytes = d->blocks / (2 * 1024);
221 if (mbytes > 0)
222 printf(" %" PRIu64 " MB.", mbytes);
223
224 printf("\n");
225}
226
227/** Register driver and enable device I/O. */
228static int ata_bd_init(void)
229{
230 void *vaddr;
231 int rc;
232
233 rc = devmap_driver_register(NAME, ata_bd_connection);
234 if (rc < 0) {
235 printf(NAME ": Unable to register driver.\n");
236 return rc;
237 }
238
239 rc = pio_enable((void *) cmd_physical, sizeof(ata_cmd_t), &vaddr);
240 if (rc != EOK) {
241 printf(NAME ": Could not initialize device I/O space.\n");
242 return rc;
243 }
244
245 cmd = vaddr;
246
247 rc = pio_enable((void *) ctl_physical, sizeof(ata_ctl_t), &vaddr);
248 if (rc != EOK) {
249 printf(NAME ": Could not initialize device I/O space.\n");
250 return rc;
251 }
252
253 ctl = vaddr;
254
255
256 return EOK;
257}
258
259/** Block device connection handler */
260static void ata_bd_connection(ipc_callid_t iid, ipc_call_t *icall)
261{
262 void *fs_va = NULL;
263 ipc_callid_t callid;
264 ipc_call_t call;
265 sysarg_t method;
266 devmap_handle_t dh;
267 unsigned int flags;
268 int retval;
269 uint64_t ba;
270 size_t cnt;
271 int disk_id, i;
272
273 /* Get the device handle. */
274 dh = IPC_GET_ARG1(*icall);
275
276 /* Determine which disk device is the client connecting to. */
277 disk_id = -1;
278 for (i = 0; i < MAX_DISKS; i++)
279 if (disk[i].devmap_handle == dh)
280 disk_id = i;
281
282 if (disk_id < 0 || disk[disk_id].present == false) {
283 async_answer_0(iid, EINVAL);
284 return;
285 }
286
287 /* Answer the IPC_M_CONNECT_ME_TO call. */
288 async_answer_0(iid, EOK);
289
290 if (!async_share_out_receive(&callid, &comm_size, &flags)) {
291 async_answer_0(callid, EHANGUP);
292 return;
293 }
294
295 fs_va = as_get_mappable_page(comm_size);
296 if (fs_va == NULL) {
297 async_answer_0(callid, EHANGUP);
298 return;
299 }
300
301 (void) async_share_out_finalize(callid, fs_va);
302
303 while (1) {
304 callid = async_get_call(&call);
305 method = IPC_GET_IMETHOD(call);
306 switch (method) {
307 case IPC_M_PHONE_HUNGUP:
308 /* The other side has hung up. */
309 async_answer_0(callid, EOK);
310 return;
311 case BD_READ_BLOCKS:
312 ba = MERGE_LOUP32(IPC_GET_ARG1(call),
313 IPC_GET_ARG2(call));
314 cnt = IPC_GET_ARG3(call);
315 if (cnt * block_size > comm_size) {
316 retval = ELIMIT;
317 break;
318 }
319 retval = ata_bd_read_blocks(disk_id, ba, cnt, fs_va);
320 break;
321 case BD_WRITE_BLOCKS:
322 ba = MERGE_LOUP32(IPC_GET_ARG1(call),
323 IPC_GET_ARG2(call));
324 cnt = IPC_GET_ARG3(call);
325 if (cnt * block_size > comm_size) {
326 retval = ELIMIT;
327 break;
328 }
329 retval = ata_bd_write_blocks(disk_id, ba, cnt, fs_va);
330 break;
331 case BD_GET_BLOCK_SIZE:
332 async_answer_1(callid, EOK, block_size);
333 continue;
334 case BD_GET_NUM_BLOCKS:
335 async_answer_2(callid, EOK, LOWER32(disk[disk_id].blocks),
336 UPPER32(disk[disk_id].blocks));
337 continue;
338 default:
339 retval = EINVAL;
340 break;
341 }
342 async_answer_0(callid, retval);
343 }
344}
345
346/** Initialize a disk.
347 *
348 * Probes for a disk, determines its parameters and initializes
349 * the disk structure.
350 */
351static int disk_init(disk_t *d, int disk_id)
352{
353 identify_data_t idata;
354 uint8_t model[40];
355 uint16_t w;
356 uint8_t c;
357 size_t pos, len;
358 int rc;
359 unsigned i;
360
361 rc = drive_identify(disk_id, &idata);
362 if (rc != EOK) {
363 d->present = false;
364 return rc;
365 }
366
367 if ((idata.caps & cap_lba) == 0) {
368 /* Device only supports CHS addressing. */
369 d->amode = am_chs;
370
371 d->geom.cylinders = idata.cylinders;
372 d->geom.heads = idata.heads;
373 d->geom.sectors = idata.sectors;
374
375 d->blocks = d->geom.cylinders * d->geom.heads * d->geom.sectors;
376 } else if ((idata.cmd_set1 & cs1_addr48) == 0) {
377 /* Device only supports LBA-28 addressing. */
378 d->amode = am_lba28;
379
380 d->geom.cylinders = 0;
381 d->geom.heads = 0;
382 d->geom.sectors = 0;
383
384 d->blocks =
385 (uint32_t) idata.total_lba28_0 |
386 ((uint32_t) idata.total_lba28_1 << 16);
387 } else {
388 /* Device supports LBA-48 addressing. */
389 d->amode = am_lba48;
390
391 d->geom.cylinders = 0;
392 d->geom.heads = 0;
393 d->geom.sectors = 0;
394
395 d->blocks =
396 (uint64_t) idata.total_lba48_0 |
397 ((uint64_t) idata.total_lba48_1 << 16) |
398 ((uint64_t) idata.total_lba48_2 << 32) |
399 ((uint64_t) idata.total_lba48_3 << 48);
400 }
401
402 /*
403 * Convert model name to string representation.
404 */
405 for (i = 0; i < 20; i++) {
406 w = idata.model_name[i];
407 model[2 * i] = w >> 8;
408 model[2 * i + 1] = w & 0x00ff;
409 }
410
411 len = 40;
412 while (len > 0 && model[len - 1] == 0x20)
413 --len;
414
415 pos = 0;
416 for (i = 0; i < len; ++i) {
417 c = model[i];
418 if (c >= 0x80) c = '?';
419
420 chr_encode(c, d->model, &pos, 40);
421 }
422 d->model[pos] = '\0';
423
424 d->present = true;
425 fibril_mutex_initialize(&d->lock);
426
427 return EOK;
428}
429
430/** Read multiple blocks from the device. */
431static int ata_bd_read_blocks(int disk_id, uint64_t ba, size_t cnt,
432 void *buf) {
433
434 int rc;
435
436 while (cnt > 0) {
437 rc = ata_bd_read_block(disk_id, ba, 1, buf);
438 if (rc != EOK)
439 return rc;
440
441 ++ba;
442 --cnt;
443 buf += block_size;
444 }
445
446 return EOK;
447}
448
449/** Write multiple blocks to the device. */
450static int ata_bd_write_blocks(int disk_id, uint64_t ba, size_t cnt,
451 const void *buf) {
452
453 int rc;
454
455 while (cnt > 0) {
456 rc = ata_bd_write_block(disk_id, ba, 1, buf);
457 if (rc != EOK)
458 return rc;
459
460 ++ba;
461 --cnt;
462 buf += block_size;
463 }
464
465 return EOK;
466}
467
468/** Issue IDENTIFY command.
469 *
470 * Reads @c identify data into the provided buffer. This is used to detect
471 * whether an ATA device is present and if so, to determine its parameters.
472 *
473 * @param disk_id Device ID, 0 or 1.
474 * @param buf Pointer to a 512-byte buffer.
475 */
476static int drive_identify(int disk_id, void *buf)
477{
478 uint16_t data;
479 uint8_t status;
480 uint8_t drv_head;
481 size_t i;
482
483 drv_head = ((disk_id != 0) ? DHR_DRV : 0);
484
485 if (wait_status(0, ~SR_BSY, NULL, TIMEOUT_PROBE) != EOK)
486 return EIO;
487
488 pio_write_8(&cmd->drive_head, drv_head);
489
490 /*
491 * This is where we would most likely expect a non-existing device to
492 * show up by not setting SR_DRDY.
493 */
494 if (wait_status(SR_DRDY, ~SR_BSY, NULL, TIMEOUT_PROBE) != EOK)
495 return EIO;
496
497 pio_write_8(&cmd->command, CMD_IDENTIFY_DRIVE);
498
499 if (wait_status(0, ~SR_BSY, &status, TIMEOUT_PROBE) != EOK)
500 return EIO;
501
502 /* Read data from the disk buffer. */
503
504 if ((status & SR_DRQ) != 0) {
505 for (i = 0; i < block_size / 2; i++) {
506 data = pio_read_16(&cmd->data_port);
507 ((uint16_t *) buf)[i] = data;
508 }
509 }
510
511 if ((status & SR_ERR) != 0)
512 return EIO;
513
514 return EOK;
515}
516
517/** Read a physical from the device.
518 *
519 * @param disk_id Device index (0 or 1)
520 * @param ba Address the first block.
521 * @param cnt Number of blocks to transfer.
522 * @param buf Buffer for holding the data.
523 *
524 * @return EOK on success, EIO on error.
525 */
526static int ata_bd_read_block(int disk_id, uint64_t ba, size_t blk_cnt,
527 void *buf)
528{
529 size_t i;
530 uint16_t data;
531 uint8_t status;
532 uint8_t drv_head;
533 disk_t *d;
534 block_coord_t bc;
535
536 d = &disk[disk_id];
537
538 /* Silence warning. */
539 memset(&bc, 0, sizeof(bc));
540
541 /* Compute block coordinates. */
542 if (coord_calc(d, ba, &bc) != EOK)
543 return EINVAL;
544
545 /* New value for Drive/Head register */
546 drv_head =
547 ((disk_id != 0) ? DHR_DRV : 0) |
548 ((d->amode != am_chs) ? DHR_LBA : 0) |
549 (bc.h & 0x0f);
550
551 fibril_mutex_lock(&d->lock);
552
553 /* Program a Read Sectors operation. */
554
555 if (wait_status(0, ~SR_BSY, NULL, TIMEOUT_BSY) != EOK) {
556 fibril_mutex_unlock(&d->lock);
557 return EIO;
558 }
559
560 pio_write_8(&cmd->drive_head, drv_head);
561
562 if (wait_status(SR_DRDY, ~SR_BSY, NULL, TIMEOUT_DRDY) != EOK) {
563 fibril_mutex_unlock(&d->lock);
564 return EIO;
565 }
566
567 /* Program block coordinates into the device. */
568 coord_sc_program(&bc, 1);
569
570 pio_write_8(&cmd->command, d->amode == am_lba48 ?
571 CMD_READ_SECTORS_EXT : CMD_READ_SECTORS);
572
573 if (wait_status(0, ~SR_BSY, &status, TIMEOUT_BSY) != EOK) {
574 fibril_mutex_unlock(&d->lock);
575 return EIO;
576 }
577
578 if ((status & SR_DRQ) != 0) {
579 /* Read data from the device buffer. */
580
581 for (i = 0; i < block_size / 2; i++) {
582 data = pio_read_16(&cmd->data_port);
583 ((uint16_t *) buf)[i] = data;
584 }
585 }
586
587 if ((status & SR_ERR) != 0)
588 return EIO;
589
590 fibril_mutex_unlock(&d->lock);
591 return EOK;
592}
593
594/** Write a physical block to the device.
595 *
596 * @param disk_id Device index (0 or 1)
597 * @param ba Address of the first block.
598 * @param cnt Number of blocks to transfer.
599 * @param buf Buffer holding the data to write.
600 *
601 * @return EOK on success, EIO on error.
602 */
603static int ata_bd_write_block(int disk_id, uint64_t ba, size_t cnt,
604 const void *buf)
605{
606 size_t i;
607 uint8_t status;
608 uint8_t drv_head;
609 disk_t *d;
610 block_coord_t bc;
611
612 d = &disk[disk_id];
613
614 /* Silence warning. */
615 memset(&bc, 0, sizeof(bc));
616
617 /* Compute block coordinates. */
618 if (coord_calc(d, ba, &bc) != EOK)
619 return EINVAL;
620
621 /* New value for Drive/Head register */
622 drv_head =
623 ((disk_id != 0) ? DHR_DRV : 0) |
624 ((d->amode != am_chs) ? DHR_LBA : 0) |
625 (bc.h & 0x0f);
626
627 fibril_mutex_lock(&d->lock);
628
629 /* Program a Write Sectors operation. */
630
631 if (wait_status(0, ~SR_BSY, NULL, TIMEOUT_BSY) != EOK) {
632 fibril_mutex_unlock(&d->lock);
633 return EIO;
634 }
635
636 pio_write_8(&cmd->drive_head, drv_head);
637
638 if (wait_status(SR_DRDY, ~SR_BSY, NULL, TIMEOUT_DRDY) != EOK) {
639 fibril_mutex_unlock(&d->lock);
640 return EIO;
641 }
642
643 /* Program block coordinates into the device. */
644 coord_sc_program(&bc, 1);
645
646 pio_write_8(&cmd->command, d->amode == am_lba48 ?
647 CMD_WRITE_SECTORS_EXT : CMD_WRITE_SECTORS);
648
649 if (wait_status(0, ~SR_BSY, &status, TIMEOUT_BSY) != EOK) {
650 fibril_mutex_unlock(&d->lock);
651 return EIO;
652 }
653
654 if ((status & SR_DRQ) != 0) {
655 /* Write data to the device buffer. */
656
657 for (i = 0; i < block_size / 2; i++) {
658 pio_write_16(&cmd->data_port, ((uint16_t *) buf)[i]);
659 }
660 }
661
662 fibril_mutex_unlock(&d->lock);
663
664 if (status & SR_ERR)
665 return EIO;
666
667 return EOK;
668}
669
670/** Calculate block coordinates.
671 *
672 * Calculates block coordinates in the best coordinate system supported
673 * by the device. These can be later programmed into the device using
674 * @c coord_sc_program().
675 *
676 * @return EOK on success or EINVAL if block index is past end of device.
677 */
678static int coord_calc(disk_t *d, uint64_t ba, block_coord_t *bc)
679{
680 uint64_t c;
681 uint64_t idx;
682
683 /* Check device bounds. */
684 if (ba >= d->blocks)
685 return EINVAL;
686
687 bc->amode = d->amode;
688
689 switch (d->amode) {
690 case am_chs:
691 /* Compute CHS coordinates. */
692 c = ba / (d->geom.heads * d->geom.sectors);
693 idx = ba % (d->geom.heads * d->geom.sectors);
694
695 bc->cyl_lo = c & 0xff;
696 bc->cyl_hi = (c >> 8) & 0xff;
697 bc->h = (idx / d->geom.sectors) & 0x0f;
698 bc->sector = (1 + (idx % d->geom.sectors)) & 0xff;
699 break;
700
701 case am_lba28:
702 /* Compute LBA-28 coordinates. */
703 bc->c0 = ba & 0xff; /* bits 0-7 */
704 bc->c1 = (ba >> 8) & 0xff; /* bits 8-15 */
705 bc->c2 = (ba >> 16) & 0xff; /* bits 16-23 */
706 bc->h = (ba >> 24) & 0x0f; /* bits 24-27 */
707 break;
708
709 case am_lba48:
710 /* Compute LBA-48 coordinates. */
711 bc->c0 = ba & 0xff; /* bits 0-7 */
712 bc->c1 = (ba >> 8) & 0xff; /* bits 8-15 */
713 bc->c2 = (ba >> 16) & 0xff; /* bits 16-23 */
714 bc->c3 = (ba >> 24) & 0xff; /* bits 24-31 */
715 bc->c4 = (ba >> 32) & 0xff; /* bits 32-39 */
716 bc->c5 = (ba >> 40) & 0xff; /* bits 40-47 */
717 bc->h = 0;
718 break;
719 }
720
721 return EOK;
722}
723
724/** Program block coordinates and sector count into ATA registers.
725 *
726 * Note that bc->h must be programmed separately into the device/head register.
727 */
728static void coord_sc_program(const block_coord_t *bc, uint16_t scnt)
729{
730 if (bc->amode == am_lba48) {
731 /* Write high-order bits. */
732 pio_write_8(&cmd->sector_count, scnt >> 8);
733 pio_write_8(&cmd->sector_number, bc->c3);
734 pio_write_8(&cmd->cylinder_low, bc->c4);
735 pio_write_8(&cmd->cylinder_high, bc->c5);
736 }
737
738 /* Write low-order bits. */
739 pio_write_8(&cmd->sector_count, scnt & 0x00ff);
740 pio_write_8(&cmd->sector_number, bc->c0);
741 pio_write_8(&cmd->cylinder_low, bc->c1);
742 pio_write_8(&cmd->cylinder_high, bc->c2);
743}
744
745/** Wait until some status bits are set and some are reset.
746 *
747 * Example: wait_status(SR_DRDY, ~SR_BSY) waits for SR_DRDY to become
748 * set and SR_BSY to become reset.
749 *
750 * @param set Combination if bits which must be all set.
751 * @param n_reset Negated combination of bits which must be all reset.
752 * @param pstatus Pointer where to store last read status or NULL.
753 * @param timeout Timeout in 10ms units.
754 *
755 * @return EOK on success, EIO on timeout.
756 */
757static int wait_status(unsigned set, unsigned n_reset, uint8_t *pstatus,
758 unsigned timeout)
759{
760 uint8_t status;
761 int cnt;
762
763 status = pio_read_8(&cmd->status);
764
765 /*
766 * This is crude, yet simple. First try with 1us delays
767 * (most likely the device will respond very fast). If not,
768 * start trying every 10 ms.
769 */
770
771 cnt = 100;
772 while ((status & ~n_reset) != 0 || (status & set) != set) {
773 async_usleep(1);
774 --cnt;
775 if (cnt <= 0) break;
776
777 status = pio_read_8(&cmd->status);
778 }
779
780 cnt = timeout;
781 while ((status & ~n_reset) != 0 || (status & set) != set) {
782 async_usleep(10000);
783 --cnt;
784 if (cnt <= 0) break;
785
786 status = pio_read_8(&cmd->status);
787 }
788
789 if (pstatus)
790 *pstatus = status;
791
792 if (cnt == 0)
793 return EIO;
794
795 return EOK;
796}
797
798/**
799 * @}
800 */
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