ide-atapi.c revision 2ac07d920604eeee8966d52e70161f9b31fe90a3 
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 */
127void 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}
140EXPORT_SYMBOL_GPL(ide_queue_pc_head);
141
142/*
143 * Add a special packet command request to the tail of the request queue,
144 * and wait for it to be serviced.
145 */
146int ide_queue_pc_tail(ide_drive_t *drive, struct gendisk *disk,
147		      struct ide_atapi_pc *pc)
148{
149	struct request *rq;
150	int error;
151
152	rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
153	rq->cmd_type = REQ_TYPE_SPECIAL;
154	rq->buffer = (char *)pc;
155	memcpy(rq->cmd, pc->c, 12);
156	if (drive->media == ide_tape)
157		rq->cmd[13] = REQ_IDETAPE_PC1;
158	error = blk_execute_rq(drive->queue, disk, rq, 0);
159	blk_put_request(rq);
160
161	return error;
162}
163EXPORT_SYMBOL_GPL(ide_queue_pc_tail);
164
165/* TODO: unify the code thus making some arguments go away */
166ide_startstop_t ide_pc_intr(ide_drive_t *drive, struct ide_atapi_pc *pc,
167	ide_handler_t *handler, unsigned int timeout, ide_expiry_t *expiry,
168	void (*update_buffers)(ide_drive_t *, struct ide_atapi_pc *),
169	void (*retry_pc)(ide_drive_t *), void (*dsc_handle)(ide_drive_t *),
170	int (*io_buffers)(ide_drive_t *, struct ide_atapi_pc *, unsigned, int))
171{
172	ide_hwif_t *hwif = drive->hwif;
173	struct request *rq = hwif->hwgroup->rq;
174	const struct ide_tp_ops *tp_ops = hwif->tp_ops;
175	xfer_func_t *xferfunc;
176	unsigned int temp;
177	u16 bcount;
178	u8 stat, ireason, scsi = drive->scsi;
179
180	debug_log("Enter %s - interrupt handler\n", __func__);
181
182	if (pc->flags & PC_FLAG_TIMEDOUT) {
183		drive->pc_callback(drive);
184		return ide_stopped;
185	}
186
187	/* Clear the interrupt */
188	stat = tp_ops->read_status(hwif);
189
190	if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
191		if (hwif->dma_ops->dma_end(drive) ||
192		    (drive->media == ide_tape && !scsi && (stat & ATA_ERR))) {
193			if (drive->media == ide_floppy && !scsi)
194				printk(KERN_ERR "%s: DMA %s error\n",
195					drive->name, rq_data_dir(pc->rq)
196						     ? "write" : "read");
197			pc->flags |= PC_FLAG_DMA_ERROR;
198		} else {
199			pc->xferred = pc->req_xfer;
200			if (update_buffers)
201				update_buffers(drive, pc);
202		}
203		debug_log("%s: DMA finished\n", drive->name);
204	}
205
206	/* No more interrupts */
207	if ((stat & ATA_DRQ) == 0) {
208		debug_log("Packet command completed, %d bytes transferred\n",
209			  pc->xferred);
210
211		pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
212
213		local_irq_enable_in_hardirq();
214
215		if (drive->media == ide_tape && !scsi &&
216		    (stat & ATA_ERR) && rq->cmd[0] == REQUEST_SENSE)
217			stat &= ~ATA_ERR;
218
219		if ((stat & ATA_ERR) || (pc->flags & PC_FLAG_DMA_ERROR)) {
220			/* Error detected */
221			debug_log("%s: I/O error\n", drive->name);
222
223			if (drive->media != ide_tape || scsi) {
224				pc->rq->errors++;
225				if (scsi)
226					goto cmd_finished;
227			}
228
229			if (rq->cmd[0] == REQUEST_SENSE) {
230				printk(KERN_ERR "%s: I/O error in request sense"
231						" command\n", drive->name);
232				return ide_do_reset(drive);
233			}
234
235			debug_log("[cmd %x]: check condition\n", rq->cmd[0]);
236
237			/* Retry operation */
238			retry_pc(drive);
239
240			/* queued, but not started */
241			return ide_stopped;
242		}
243cmd_finished:
244		pc->error = 0;
245		if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) &&
246		    (stat & ATA_DSC) == 0) {
247			dsc_handle(drive);
248			return ide_stopped;
249		}
250
251		/* Command finished - Call the callback function */
252		drive->pc_callback(drive);
253
254		return ide_stopped;
255	}
256
257	if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
258		pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
259		printk(KERN_ERR "%s: The device wants to issue more interrupts "
260				"in DMA mode\n", drive->name);
261		ide_dma_off(drive);
262		return ide_do_reset(drive);
263	}
264
265	/* Get the number of bytes to transfer on this interrupt. */
266	ide_read_bcount_and_ireason(drive, &bcount, &ireason);
267
268	if (ireason & ATAPI_COD) {
269		printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__);
270		return ide_do_reset(drive);
271	}
272
273	if (((ireason & ATAPI_IO) == ATAPI_IO) ==
274		!!(pc->flags & PC_FLAG_WRITING)) {
275		/* Hopefully, we will never get here */
276		printk(KERN_ERR "%s: We wanted to %s, but the device wants us "
277				"to %s!\n", drive->name,
278				(ireason & ATAPI_IO) ? "Write" : "Read",
279				(ireason & ATAPI_IO) ? "Read" : "Write");
280		return ide_do_reset(drive);
281	}
282
283	if (!(pc->flags & PC_FLAG_WRITING)) {
284		/* Reading - Check that we have enough space */
285		temp = pc->xferred + bcount;
286		if (temp > pc->req_xfer) {
287			if (temp > pc->buf_size) {
288				printk(KERN_ERR "%s: The device wants to send "
289						"us more data than expected - "
290						"discarding data\n",
291						drive->name);
292				if (scsi)
293					temp = pc->buf_size - pc->xferred;
294				else
295					temp = 0;
296				if (temp) {
297					if (pc->sg)
298						io_buffers(drive, pc, temp, 0);
299					else
300						tp_ops->input_data(drive, NULL,
301							pc->cur_pos, temp);
302					printk(KERN_ERR "%s: transferred %d of "
303							"%d bytes\n",
304							drive->name,
305							temp, bcount);
306				}
307				pc->xferred += temp;
308				pc->cur_pos += temp;
309				ide_pad_transfer(drive, 0, bcount - temp);
310				ide_set_handler(drive, handler, timeout,
311						expiry);
312				return ide_started;
313			}
314			debug_log("The device wants to send us more data than "
315				  "expected - allowing transfer\n");
316		}
317		xferfunc = tp_ops->input_data;
318	} else
319		xferfunc = tp_ops->output_data;
320
321	if ((drive->media == ide_floppy && !scsi && !pc->buf) ||
322	    (drive->media == ide_tape && !scsi && pc->bh) ||
323	    (scsi && pc->sg)) {
324		int done = io_buffers(drive, pc, bcount,
325				  !!(pc->flags & PC_FLAG_WRITING));
326
327		/* FIXME: don't do partial completions */
328		if (drive->media == ide_floppy && !scsi)
329			ide_end_request(drive, 1, done >> 9);
330	} else
331		xferfunc(drive, NULL, pc->cur_pos, bcount);
332
333	/* Update the current position */
334	pc->xferred += bcount;
335	pc->cur_pos += bcount;
336
337	debug_log("[cmd %x] transferred %d bytes on that intr.\n",
338		  rq->cmd[0], bcount);
339
340	/* And set the interrupt handler again */
341	ide_set_handler(drive, handler, timeout, expiry);
342	return ide_started;
343}
344EXPORT_SYMBOL_GPL(ide_pc_intr);
345
346static u8 ide_read_ireason(ide_drive_t *drive)
347{
348	ide_task_t task;
349
350	memset(&task, 0, sizeof(task));
351	task.tf_flags = IDE_TFLAG_IN_NSECT;
352
353	drive->hwif->tp_ops->tf_read(drive, &task);
354
355	return task.tf.nsect & 3;
356}
357
358static u8 ide_wait_ireason(ide_drive_t *drive, u8 ireason)
359{
360	int retries = 100;
361
362	while (retries-- && ((ireason & ATAPI_COD) == 0 ||
363		(ireason & ATAPI_IO))) {
364		printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
365				"a packet command, retrying\n", drive->name);
366		udelay(100);
367		ireason = ide_read_ireason(drive);
368		if (retries == 0) {
369			printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
370					"a packet command, ignoring\n",
371					drive->name);
372			ireason |= ATAPI_COD;
373			ireason &= ~ATAPI_IO;
374		}
375	}
376
377	return ireason;
378}
379
380ide_startstop_t ide_transfer_pc(ide_drive_t *drive, struct ide_atapi_pc *pc,
381				ide_handler_t *handler, unsigned int timeout,
382				ide_expiry_t *expiry)
383{
384	ide_hwif_t *hwif = drive->hwif;
385	struct request *rq = hwif->hwgroup->rq;
386	ide_startstop_t startstop;
387	u8 ireason;
388
389	if (ide_wait_stat(&startstop, drive, ATA_DRQ, ATA_BUSY, WAIT_READY)) {
390		printk(KERN_ERR "%s: Strange, packet command initiated yet "
391				"DRQ isn't asserted\n", drive->name);
392		return startstop;
393	}
394
395	ireason = ide_read_ireason(drive);
396	if (drive->media == ide_tape && !drive->scsi)
397		ireason = ide_wait_ireason(drive, ireason);
398
399	if ((ireason & ATAPI_COD) == 0 || (ireason & ATAPI_IO)) {
400		printk(KERN_ERR "%s: (IO,CoD) != (0,1) while issuing "
401				"a packet command\n", drive->name);
402		return ide_do_reset(drive);
403	}
404
405	/* Set the interrupt routine */
406	ide_set_handler(drive, handler, timeout, expiry);
407
408	/* Begin DMA, if necessary */
409	if (pc->flags & PC_FLAG_DMA_OK) {
410		pc->flags |= PC_FLAG_DMA_IN_PROGRESS;
411		hwif->dma_ops->dma_start(drive);
412	}
413
414	/* Send the actual packet */
415	if ((drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) == 0)
416		hwif->tp_ops->output_data(drive, NULL, rq->cmd, 12);
417
418	return ide_started;
419}
420EXPORT_SYMBOL_GPL(ide_transfer_pc);
421
422ide_startstop_t ide_issue_pc(ide_drive_t *drive, struct ide_atapi_pc *pc,
423			     ide_handler_t *handler, unsigned int timeout,
424			     ide_expiry_t *expiry)
425{
426	ide_hwif_t *hwif = drive->hwif;
427	u16 bcount;
428	u8 dma = 0;
429
430	/* We haven't transferred any data yet */
431	pc->xferred = 0;
432	pc->cur_pos = pc->buf;
433
434	/* Request to transfer the entire buffer at once */
435	if (drive->media == ide_tape && !drive->scsi)
436		bcount = pc->req_xfer;
437	else
438		bcount = min(pc->req_xfer, 63 * 1024);
439
440	if (pc->flags & PC_FLAG_DMA_ERROR) {
441		pc->flags &= ~PC_FLAG_DMA_ERROR;
442		ide_dma_off(drive);
443	}
444
445	if ((pc->flags & PC_FLAG_DMA_OK) && drive->using_dma) {
446		if (drive->scsi)
447			hwif->sg_mapped = 1;
448		dma = !hwif->dma_ops->dma_setup(drive);
449		if (drive->scsi)
450			hwif->sg_mapped = 0;
451	}
452
453	if (!dma)
454		pc->flags &= ~PC_FLAG_DMA_OK;
455
456	ide_pktcmd_tf_load(drive, drive->scsi ? 0 : IDE_TFLAG_OUT_DEVICE,
457			   bcount, dma);
458
459	/* Issue the packet command */
460	if (drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT) {
461		ide_execute_command(drive, ATA_CMD_PACKET, handler,
462				    timeout, NULL);
463		return ide_started;
464	} else {
465		ide_execute_pkt_cmd(drive);
466		return (*handler)(drive);
467	}
468}
469EXPORT_SYMBOL_GPL(ide_issue_pc);
470