ide-atapi.c revision baf08f0be6d986521bb2fbdc7af51fc4847da734
1/*
2 * ATAPI support.
3 */
4
5#include <linux/kernel.h>
6#include <linux/delay.h>
7#include <linux/ide.h>
8#include <scsi/scsi.h>
9
10#ifdef DEBUG
11#define debug_log(fmt, args...) \
12	printk(KERN_INFO "ide: " fmt, ## args)
13#else
14#define debug_log(fmt, args...) do {} while (0)
15#endif
16
17/*
18 * Check whether we can support a device,
19 * based on the ATAPI IDENTIFY command results.
20 */
21int ide_check_atapi_device(ide_drive_t *drive, const char *s)
22{
23	u16 *id = drive->id;
24	u8 gcw[2], protocol, device_type, removable, drq_type, packet_size;
25
26	*((u16 *)&gcw) = id[ATA_ID_CONFIG];
27
28	protocol    = (gcw[1] & 0xC0) >> 6;
29	device_type =  gcw[1] & 0x1F;
30	removable   = (gcw[0] & 0x80) >> 7;
31	drq_type    = (gcw[0] & 0x60) >> 5;
32	packet_size =  gcw[0] & 0x03;
33
34#ifdef CONFIG_PPC
35	/* kludge for Apple PowerBook internal zip */
36	if (drive->media == ide_floppy && device_type == 5 &&
37	    !strstr((char *)&id[ATA_ID_PROD], "CD-ROM") &&
38	    strstr((char *)&id[ATA_ID_PROD], "ZIP"))
39		device_type = 0;
40#endif
41
42	if (protocol != 2)
43		printk(KERN_ERR "%s: %s: protocol (0x%02x) is not ATAPI\n",
44			s, drive->name, protocol);
45	else if ((drive->media == ide_floppy && device_type != 0) ||
46		 (drive->media == ide_tape && device_type != 1))
47		printk(KERN_ERR "%s: %s: invalid device type (0x%02x)\n",
48			s, drive->name, device_type);
49	else if (removable == 0)
50		printk(KERN_ERR "%s: %s: the removable flag is not set\n",
51			s, drive->name);
52	else if (drive->media == ide_floppy && drq_type == 3)
53		printk(KERN_ERR "%s: %s: sorry, DRQ type (0x%02x) not "
54			"supported\n", s, drive->name, drq_type);
55	else if (packet_size != 0)
56		printk(KERN_ERR "%s: %s: packet size (0x%02x) is not 12 "
57			"bytes\n", s, drive->name, packet_size);
58	else
59		return 1;
60	return 0;
61}
62EXPORT_SYMBOL_GPL(ide_check_atapi_device);
63
64/* PIO data transfer routine using the scatter gather table. */
65int ide_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
66		    unsigned int bcount, int write)
67{
68	ide_hwif_t *hwif = drive->hwif;
69	const struct ide_tp_ops *tp_ops = hwif->tp_ops;
70	xfer_func_t *xf = write ? tp_ops->output_data : tp_ops->input_data;
71	struct scatterlist *sg = pc->sg;
72	char *buf;
73	int count, done = 0;
74
75	while (bcount) {
76		count = min(sg->length - pc->b_count, bcount);
77
78		if (PageHighMem(sg_page(sg))) {
79			unsigned long flags;
80
81			local_irq_save(flags);
82			buf = kmap_atomic(sg_page(sg), KM_IRQ0) + sg->offset;
83			xf(drive, NULL, buf + pc->b_count, count);
84			kunmap_atomic(buf - sg->offset, KM_IRQ0);
85			local_irq_restore(flags);
86		} else {
87			buf = sg_virt(sg);
88			xf(drive, NULL, buf + pc->b_count, count);
89		}
90
91		bcount -= count;
92		pc->b_count += count;
93		done += count;
94
95		if (pc->b_count == sg->length) {
96			if (!--pc->sg_cnt)
97				break;
98			pc->sg = sg = sg_next(sg);
99			pc->b_count = 0;
100		}
101	}
102
103	if (bcount) {
104		printk(KERN_ERR "%s: %d leftover bytes, %s\n", drive->name,
105			bcount, write ? "padding with zeros"
106				      : "discarding data");
107		ide_pad_transfer(drive, write, bcount);
108	}
109
110	return done;
111}
112EXPORT_SYMBOL_GPL(ide_io_buffers);
113
114void ide_init_pc(struct ide_atapi_pc *pc)
115{
116	memset(pc, 0, sizeof(*pc));
117	pc->buf = pc->pc_buf;
118	pc->buf_size = IDE_PC_BUFFER_SIZE;
119}
120EXPORT_SYMBOL_GPL(ide_init_pc);
121
122/*
123 * Generate a new packet command request in front of the request queue, before
124 * the current request, so that it will be processed immediately, on the next
125 * pass through the driver.
126 */
127static void ide_queue_pc_head(ide_drive_t *drive, struct gendisk *disk,
128			      struct ide_atapi_pc *pc, struct request *rq)
129{
130	blk_rq_init(NULL, rq);
131	rq->cmd_type = REQ_TYPE_SPECIAL;
132	rq->cmd_flags |= REQ_PREEMPT;
133	rq->buffer = (char *)pc;
134	rq->rq_disk = disk;
135	memcpy(rq->cmd, pc->c, 12);
136	if (drive->media == ide_tape)
137		rq->cmd[13] = REQ_IDETAPE_PC1;
138	ide_do_drive_cmd(drive, rq);
139}
140
141/*
142 * Add a special packet command request to the tail of the request queue,
143 * and wait for it to be serviced.
144 */
145int ide_queue_pc_tail(ide_drive_t *drive, struct gendisk *disk,
146		      struct ide_atapi_pc *pc)
147{
148	struct request *rq;
149	int error;
150
151	rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
152	rq->cmd_type = REQ_TYPE_SPECIAL;
153	rq->buffer = (char *)pc;
154	memcpy(rq->cmd, pc->c, 12);
155	if (drive->media == ide_tape)
156		rq->cmd[13] = REQ_IDETAPE_PC1;
157	error = blk_execute_rq(drive->queue, disk, rq, 0);
158	blk_put_request(rq);
159
160	return error;
161}
162EXPORT_SYMBOL_GPL(ide_queue_pc_tail);
163
164int ide_do_test_unit_ready(ide_drive_t *drive, struct gendisk *disk)
165{
166	struct ide_atapi_pc pc;
167
168	ide_init_pc(&pc);
169	pc.c[0] = TEST_UNIT_READY;
170
171	return ide_queue_pc_tail(drive, disk, &pc);
172}
173EXPORT_SYMBOL_GPL(ide_do_test_unit_ready);
174
175int ide_do_start_stop(ide_drive_t *drive, struct gendisk *disk, int start)
176{
177	struct ide_atapi_pc pc;
178
179	ide_init_pc(&pc);
180	pc.c[0] = START_STOP;
181	pc.c[4] = start;
182
183	if (drive->media == ide_tape)
184		pc.flags |= PC_FLAG_WAIT_FOR_DSC;
185
186	return ide_queue_pc_tail(drive, disk, &pc);
187}
188EXPORT_SYMBOL_GPL(ide_do_start_stop);
189
190int ide_set_media_lock(ide_drive_t *drive, struct gendisk *disk, int on)
191{
192	struct ide_atapi_pc pc;
193
194	if (drive->atapi_flags & IDE_AFLAG_NO_DOORLOCK)
195		return 0;
196
197	ide_init_pc(&pc);
198	pc.c[0] = ALLOW_MEDIUM_REMOVAL;
199	pc.c[4] = on;
200
201	return ide_queue_pc_tail(drive, disk, &pc);
202}
203EXPORT_SYMBOL_GPL(ide_set_media_lock);
204
205void ide_create_request_sense_cmd(ide_drive_t *drive, struct ide_atapi_pc *pc)
206{
207	ide_init_pc(pc);
208	pc->c[0] = REQUEST_SENSE;
209	if (drive->media == ide_floppy) {
210		pc->c[4] = 255;
211		pc->req_xfer = 18;
212	} else {
213		pc->c[4] = 20;
214		pc->req_xfer = 20;
215	}
216}
217EXPORT_SYMBOL_GPL(ide_create_request_sense_cmd);
218
219/*
220 * Called when an error was detected during the last packet command.
221 * We queue a request sense packet command in the head of the request list.
222 */
223void ide_retry_pc(ide_drive_t *drive, struct gendisk *disk)
224{
225	struct request *rq = &drive->request_sense_rq;
226	struct ide_atapi_pc *pc = &drive->request_sense_pc;
227
228	(void)ide_read_error(drive);
229	ide_create_request_sense_cmd(drive, pc);
230	if (drive->media == ide_tape)
231		set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags);
232	ide_queue_pc_head(drive, disk, pc, rq);
233}
234EXPORT_SYMBOL_GPL(ide_retry_pc);
235
236int ide_scsi_expiry(ide_drive_t *drive)
237{
238	struct ide_atapi_pc *pc = drive->pc;
239
240	debug_log("%s called for %lu at %lu\n", __func__,
241		  pc->scsi_cmd->serial_number, jiffies);
242
243	pc->flags |= PC_FLAG_TIMEDOUT;
244
245	return 0; /* we do not want the IDE subsystem to retry */
246}
247EXPORT_SYMBOL_GPL(ide_scsi_expiry);
248
249/*
250 * This is the usual interrupt handler which will be called during a packet
251 * command.  We will transfer some of the data (as requested by the drive)
252 * and will re-point interrupt handler to us.
253 */
254static ide_startstop_t ide_pc_intr(ide_drive_t *drive)
255{
256	struct ide_atapi_pc *pc = drive->pc;
257	ide_hwif_t *hwif = drive->hwif;
258	struct request *rq = hwif->hwgroup->rq;
259	const struct ide_tp_ops *tp_ops = hwif->tp_ops;
260	xfer_func_t *xferfunc;
261	ide_expiry_t *expiry;
262	unsigned int timeout, temp;
263	u16 bcount;
264	u8 stat, ireason, scsi = drive->scsi, dsc = 0;
265
266	debug_log("Enter %s - interrupt handler\n", __func__);
267
268	if (scsi) {
269		timeout = ide_scsi_get_timeout(pc);
270		expiry = ide_scsi_expiry;
271	} else {
272		timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
273						       : WAIT_TAPE_CMD;
274		expiry = NULL;
275	}
276
277	if (pc->flags & PC_FLAG_TIMEDOUT) {
278		drive->pc_callback(drive, 0);
279		return ide_stopped;
280	}
281
282	/* Clear the interrupt */
283	stat = tp_ops->read_status(hwif);
284
285	if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
286		if (hwif->dma_ops->dma_end(drive) ||
287		    (drive->media == ide_tape && !scsi && (stat & ATA_ERR))) {
288			if (drive->media == ide_floppy && !scsi)
289				printk(KERN_ERR "%s: DMA %s error\n",
290					drive->name, rq_data_dir(pc->rq)
291						     ? "write" : "read");
292			pc->flags |= PC_FLAG_DMA_ERROR;
293		} else {
294			pc->xferred = pc->req_xfer;
295			if (drive->pc_update_buffers)
296				drive->pc_update_buffers(drive, pc);
297		}
298		debug_log("%s: DMA finished\n", drive->name);
299	}
300
301	/* No more interrupts */
302	if ((stat & ATA_DRQ) == 0) {
303		debug_log("Packet command completed, %d bytes transferred\n",
304			  pc->xferred);
305
306		pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
307
308		local_irq_enable_in_hardirq();
309
310		if (drive->media == ide_tape && !scsi &&
311		    (stat & ATA_ERR) && rq->cmd[0] == REQUEST_SENSE)
312			stat &= ~ATA_ERR;
313
314		if ((stat & ATA_ERR) || (pc->flags & PC_FLAG_DMA_ERROR)) {
315			/* Error detected */
316			debug_log("%s: I/O error\n", drive->name);
317
318			if (drive->media != ide_tape || scsi) {
319				pc->rq->errors++;
320				if (scsi)
321					goto cmd_finished;
322			}
323
324			if (rq->cmd[0] == REQUEST_SENSE) {
325				printk(KERN_ERR "%s: I/O error in request sense"
326						" command\n", drive->name);
327				return ide_do_reset(drive);
328			}
329
330			debug_log("[cmd %x]: check condition\n", rq->cmd[0]);
331
332			/* Retry operation */
333			ide_retry_pc(drive, rq->rq_disk);
334
335			/* queued, but not started */
336			return ide_stopped;
337		}
338cmd_finished:
339		pc->error = 0;
340
341		if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) && (stat & ATA_DSC) == 0)
342			dsc = 1;
343
344		/* Command finished - Call the callback function */
345		drive->pc_callback(drive, dsc);
346
347		return ide_stopped;
348	}
349
350	if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
351		pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
352		printk(KERN_ERR "%s: The device wants to issue more interrupts "
353				"in DMA mode\n", drive->name);
354		ide_dma_off(drive);
355		return ide_do_reset(drive);
356	}
357
358	/* Get the number of bytes to transfer on this interrupt. */
359	ide_read_bcount_and_ireason(drive, &bcount, &ireason);
360
361	if (ireason & ATAPI_COD) {
362		printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__);
363		return ide_do_reset(drive);
364	}
365
366	if (((ireason & ATAPI_IO) == ATAPI_IO) ==
367		!!(pc->flags & PC_FLAG_WRITING)) {
368		/* Hopefully, we will never get here */
369		printk(KERN_ERR "%s: We wanted to %s, but the device wants us "
370				"to %s!\n", drive->name,
371				(ireason & ATAPI_IO) ? "Write" : "Read",
372				(ireason & ATAPI_IO) ? "Read" : "Write");
373		return ide_do_reset(drive);
374	}
375
376	if (!(pc->flags & PC_FLAG_WRITING)) {
377		/* Reading - Check that we have enough space */
378		temp = pc->xferred + bcount;
379		if (temp > pc->req_xfer) {
380			if (temp > pc->buf_size) {
381				printk(KERN_ERR "%s: The device wants to send "
382						"us more data than expected - "
383						"discarding data\n",
384						drive->name);
385				if (scsi)
386					temp = pc->buf_size - pc->xferred;
387				else
388					temp = 0;
389				if (temp) {
390					if (pc->sg)
391						drive->pc_io_buffers(drive, pc,
392								     temp, 0);
393					else
394						tp_ops->input_data(drive, NULL,
395							pc->cur_pos, temp);
396					printk(KERN_ERR "%s: transferred %d of "
397							"%d bytes\n",
398							drive->name,
399							temp, bcount);
400				}
401				pc->xferred += temp;
402				pc->cur_pos += temp;
403				ide_pad_transfer(drive, 0, bcount - temp);
404				goto next_irq;
405			}
406			debug_log("The device wants to send us more data than "
407				  "expected - allowing transfer\n");
408		}
409		xferfunc = tp_ops->input_data;
410	} else
411		xferfunc = tp_ops->output_data;
412
413	if ((drive->media == ide_floppy && !scsi && !pc->buf) ||
414	    (drive->media == ide_tape && !scsi && pc->bh) ||
415	    (scsi && pc->sg)) {
416		int done = drive->pc_io_buffers(drive, pc, bcount,
417				  !!(pc->flags & PC_FLAG_WRITING));
418
419		/* FIXME: don't do partial completions */
420		if (drive->media == ide_floppy && !scsi)
421			ide_end_request(drive, 1, done >> 9);
422	} else
423		xferfunc(drive, NULL, pc->cur_pos, bcount);
424
425	/* Update the current position */
426	pc->xferred += bcount;
427	pc->cur_pos += bcount;
428
429	debug_log("[cmd %x] transferred %d bytes on that intr.\n",
430		  rq->cmd[0], bcount);
431next_irq:
432	/* And set the interrupt handler again */
433	ide_set_handler(drive, ide_pc_intr, timeout, expiry);
434	return ide_started;
435}
436
437static u8 ide_read_ireason(ide_drive_t *drive)
438{
439	ide_task_t task;
440
441	memset(&task, 0, sizeof(task));
442	task.tf_flags = IDE_TFLAG_IN_NSECT;
443
444	drive->hwif->tp_ops->tf_read(drive, &task);
445
446	return task.tf.nsect & 3;
447}
448
449static u8 ide_wait_ireason(ide_drive_t *drive, u8 ireason)
450{
451	int retries = 100;
452
453	while (retries-- && ((ireason & ATAPI_COD) == 0 ||
454		(ireason & ATAPI_IO))) {
455		printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
456				"a packet command, retrying\n", drive->name);
457		udelay(100);
458		ireason = ide_read_ireason(drive);
459		if (retries == 0) {
460			printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
461					"a packet command, ignoring\n",
462					drive->name);
463			ireason |= ATAPI_COD;
464			ireason &= ~ATAPI_IO;
465		}
466	}
467
468	return ireason;
469}
470
471static int ide_delayed_transfer_pc(ide_drive_t *drive)
472{
473	/* Send the actual packet */
474	drive->hwif->tp_ops->output_data(drive, NULL, drive->pc->c, 12);
475
476	/* Timeout for the packet command */
477	return WAIT_FLOPPY_CMD;
478}
479
480static ide_startstop_t ide_transfer_pc(ide_drive_t *drive)
481{
482	struct ide_atapi_pc *pc = drive->pc;
483	ide_hwif_t *hwif = drive->hwif;
484	struct request *rq = hwif->hwgroup->rq;
485	ide_expiry_t *expiry;
486	unsigned int timeout;
487	ide_startstop_t startstop;
488	u8 ireason;
489
490	if (ide_wait_stat(&startstop, drive, ATA_DRQ, ATA_BUSY, WAIT_READY)) {
491		printk(KERN_ERR "%s: Strange, packet command initiated yet "
492				"DRQ isn't asserted\n", drive->name);
493		return startstop;
494	}
495
496	ireason = ide_read_ireason(drive);
497	if (drive->media == ide_tape && !drive->scsi)
498		ireason = ide_wait_ireason(drive, ireason);
499
500	if ((ireason & ATAPI_COD) == 0 || (ireason & ATAPI_IO)) {
501		printk(KERN_ERR "%s: (IO,CoD) != (0,1) while issuing "
502				"a packet command\n", drive->name);
503		return ide_do_reset(drive);
504	}
505
506	/*
507	 * If necessary schedule the packet transfer to occur 'timeout'
508	 * miliseconds later in ide_delayed_transfer_pc() after the device
509	 * says it's ready for a packet.
510	 */
511	if (drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) {
512		timeout = drive->pc_delay;
513		expiry = &ide_delayed_transfer_pc;
514	} else {
515		if (drive->scsi) {
516			timeout = ide_scsi_get_timeout(pc);
517			expiry = ide_scsi_expiry;
518		} else {
519			timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
520							       : WAIT_TAPE_CMD;
521			expiry = NULL;
522		}
523	}
524
525	/* Set the interrupt routine */
526	ide_set_handler(drive, ide_pc_intr, timeout, expiry);
527
528	/* Begin DMA, if necessary */
529	if (pc->flags & PC_FLAG_DMA_OK) {
530		pc->flags |= PC_FLAG_DMA_IN_PROGRESS;
531		hwif->dma_ops->dma_start(drive);
532	}
533
534	/* Send the actual packet */
535	if ((drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) == 0)
536		hwif->tp_ops->output_data(drive, NULL, rq->cmd, 12);
537
538	return ide_started;
539}
540
541ide_startstop_t ide_issue_pc(ide_drive_t *drive, unsigned int timeout,
542			     ide_expiry_t *expiry)
543{
544	struct ide_atapi_pc *pc = drive->pc;
545	ide_hwif_t *hwif = drive->hwif;
546	u16 bcount;
547	u8 dma = 0;
548
549	/* We haven't transferred any data yet */
550	pc->xferred = 0;
551	pc->cur_pos = pc->buf;
552
553	/* Request to transfer the entire buffer at once */
554	if (drive->media == ide_tape && !drive->scsi)
555		bcount = pc->req_xfer;
556	else
557		bcount = min(pc->req_xfer, 63 * 1024);
558
559	if (pc->flags & PC_FLAG_DMA_ERROR) {
560		pc->flags &= ~PC_FLAG_DMA_ERROR;
561		ide_dma_off(drive);
562	}
563
564	if ((pc->flags & PC_FLAG_DMA_OK) && drive->using_dma) {
565		if (drive->scsi)
566			hwif->sg_mapped = 1;
567		dma = !hwif->dma_ops->dma_setup(drive);
568		if (drive->scsi)
569			hwif->sg_mapped = 0;
570	}
571
572	if (!dma)
573		pc->flags &= ~PC_FLAG_DMA_OK;
574
575	ide_pktcmd_tf_load(drive, drive->scsi ? 0 : IDE_TFLAG_OUT_DEVICE,
576			   bcount, dma);
577
578	/* Issue the packet command */
579	if (drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT) {
580		ide_execute_command(drive, ATA_CMD_PACKET, ide_transfer_pc,
581				    timeout, NULL);
582		return ide_started;
583	} else {
584		ide_execute_pkt_cmd(drive);
585		return ide_transfer_pc(drive);
586	}
587}
588EXPORT_SYMBOL_GPL(ide_issue_pc);
589