xref: /openbmc/linux/drivers/cdrom/gdrom.c (revision 750afb08)
1 /* GD ROM driver for the SEGA Dreamcast
2  * copyright Adrian McMenamin, 2007
3  * With thanks to Marcus Comstedt and Nathan Keynes
4  * for work in reversing PIO and DMA
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License along
17  * with this program; if not, write to the Free Software Foundation, Inc.,
18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19  *
20  */
21 
22 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
23 
24 #include <linux/init.h>
25 #include <linux/module.h>
26 #include <linux/fs.h>
27 #include <linux/kernel.h>
28 #include <linux/list.h>
29 #include <linux/slab.h>
30 #include <linux/dma-mapping.h>
31 #include <linux/cdrom.h>
32 #include <linux/genhd.h>
33 #include <linux/bio.h>
34 #include <linux/blk-mq.h>
35 #include <linux/interrupt.h>
36 #include <linux/device.h>
37 #include <linux/mutex.h>
38 #include <linux/wait.h>
39 #include <linux/platform_device.h>
40 #include <scsi/scsi.h>
41 #include <asm/io.h>
42 #include <asm/dma.h>
43 #include <asm/delay.h>
44 #include <mach/dma.h>
45 #include <mach/sysasic.h>
46 
47 #define GDROM_DEV_NAME "gdrom"
48 #define GD_SESSION_OFFSET 150
49 
50 /* GD Rom commands */
51 #define GDROM_COM_SOFTRESET 0x08
52 #define GDROM_COM_EXECDIAG 0x90
53 #define GDROM_COM_PACKET 0xA0
54 #define GDROM_COM_IDDEV 0xA1
55 
56 /* GD Rom registers */
57 #define GDROM_BASE_REG			0xA05F7000
58 #define GDROM_ALTSTATUS_REG		(GDROM_BASE_REG + 0x18)
59 #define GDROM_DATA_REG			(GDROM_BASE_REG + 0x80)
60 #define GDROM_ERROR_REG		(GDROM_BASE_REG + 0x84)
61 #define GDROM_INTSEC_REG		(GDROM_BASE_REG + 0x88)
62 #define GDROM_SECNUM_REG		(GDROM_BASE_REG + 0x8C)
63 #define GDROM_BCL_REG			(GDROM_BASE_REG + 0x90)
64 #define GDROM_BCH_REG			(GDROM_BASE_REG + 0x94)
65 #define GDROM_DSEL_REG			(GDROM_BASE_REG + 0x98)
66 #define GDROM_STATUSCOMMAND_REG	(GDROM_BASE_REG + 0x9C)
67 #define GDROM_RESET_REG		(GDROM_BASE_REG + 0x4E4)
68 
69 #define GDROM_DMA_STARTADDR_REG	(GDROM_BASE_REG + 0x404)
70 #define GDROM_DMA_LENGTH_REG		(GDROM_BASE_REG + 0x408)
71 #define GDROM_DMA_DIRECTION_REG	(GDROM_BASE_REG + 0x40C)
72 #define GDROM_DMA_ENABLE_REG		(GDROM_BASE_REG + 0x414)
73 #define GDROM_DMA_STATUS_REG		(GDROM_BASE_REG + 0x418)
74 #define GDROM_DMA_WAIT_REG		(GDROM_BASE_REG + 0x4A0)
75 #define GDROM_DMA_ACCESS_CTRL_REG	(GDROM_BASE_REG + 0x4B8)
76 
77 #define GDROM_HARD_SECTOR	2048
78 #define BLOCK_LAYER_SECTOR	512
79 #define GD_TO_BLK		4
80 
81 #define GDROM_DEFAULT_TIMEOUT	(HZ * 7)
82 
83 static DEFINE_MUTEX(gdrom_mutex);
84 static const struct {
85 	int sense_key;
86 	const char * const text;
87 } sense_texts[] = {
88 	{NO_SENSE, "OK"},
89 	{RECOVERED_ERROR, "Recovered from error"},
90 	{NOT_READY, "Device not ready"},
91 	{MEDIUM_ERROR, "Disk not ready"},
92 	{HARDWARE_ERROR, "Hardware error"},
93 	{ILLEGAL_REQUEST, "Command has failed"},
94 	{UNIT_ATTENTION, "Device needs attention - disk may have been changed"},
95 	{DATA_PROTECT, "Data protection error"},
96 	{ABORTED_COMMAND, "Command aborted"},
97 };
98 
99 static struct platform_device *pd;
100 static int gdrom_major;
101 static DECLARE_WAIT_QUEUE_HEAD(command_queue);
102 static DECLARE_WAIT_QUEUE_HEAD(request_queue);
103 
104 struct gdromtoc {
105 	unsigned int entry[99];
106 	unsigned int first, last;
107 	unsigned int leadout;
108 };
109 
110 static struct gdrom_unit {
111 	struct gendisk *disk;
112 	struct cdrom_device_info *cd_info;
113 	int status;
114 	int pending;
115 	int transfer;
116 	char disk_type;
117 	struct gdromtoc *toc;
118 	struct request_queue *gdrom_rq;
119 	struct blk_mq_tag_set tag_set;
120 } gd;
121 
122 struct gdrom_id {
123 	char mid;
124 	char modid;
125 	char verid;
126 	char padA[13];
127 	char mname[16];
128 	char modname[16];
129 	char firmver[16];
130 	char padB[16];
131 };
132 
133 static int gdrom_getsense(short *bufstring);
134 static int gdrom_packetcommand(struct cdrom_device_info *cd_info,
135 	struct packet_command *command);
136 static int gdrom_hardreset(struct cdrom_device_info *cd_info);
137 
138 static bool gdrom_is_busy(void)
139 {
140 	return (__raw_readb(GDROM_ALTSTATUS_REG) & 0x80) != 0;
141 }
142 
143 static bool gdrom_data_request(void)
144 {
145 	return (__raw_readb(GDROM_ALTSTATUS_REG) & 0x88) == 8;
146 }
147 
148 static bool gdrom_wait_clrbusy(void)
149 {
150 	unsigned long timeout = jiffies + GDROM_DEFAULT_TIMEOUT;
151 	while ((__raw_readb(GDROM_ALTSTATUS_REG) & 0x80) &&
152 		(time_before(jiffies, timeout)))
153 		cpu_relax();
154 	return time_before(jiffies, timeout + 1);
155 }
156 
157 static bool gdrom_wait_busy_sleeps(void)
158 {
159 	unsigned long timeout;
160 	/* Wait to get busy first */
161 	timeout = jiffies + GDROM_DEFAULT_TIMEOUT;
162 	while (!gdrom_is_busy() && time_before(jiffies, timeout))
163 		cpu_relax();
164 	/* Now wait for busy to clear */
165 	return gdrom_wait_clrbusy();
166 }
167 
168 static void gdrom_identifydevice(void *buf)
169 {
170 	int c;
171 	short *data = buf;
172 	/* If the device won't clear it has probably
173 	* been hit by a serious failure - but we'll
174 	* try to return a sense key even so */
175 	if (!gdrom_wait_clrbusy()) {
176 		gdrom_getsense(NULL);
177 		return;
178 	}
179 	__raw_writeb(GDROM_COM_IDDEV, GDROM_STATUSCOMMAND_REG);
180 	if (!gdrom_wait_busy_sleeps()) {
181 		gdrom_getsense(NULL);
182 		return;
183 	}
184 	/* now read in the data */
185 	for (c = 0; c < 40; c++)
186 		data[c] = __raw_readw(GDROM_DATA_REG);
187 }
188 
189 static void gdrom_spicommand(void *spi_string, int buflen)
190 {
191 	short *cmd = spi_string;
192 	unsigned long timeout;
193 
194 	/* ensure IRQ_WAIT is set */
195 	__raw_writeb(0x08, GDROM_ALTSTATUS_REG);
196 	/* specify how many bytes we expect back */
197 	__raw_writeb(buflen & 0xFF, GDROM_BCL_REG);
198 	__raw_writeb((buflen >> 8) & 0xFF, GDROM_BCH_REG);
199 	/* other parameters */
200 	__raw_writeb(0, GDROM_INTSEC_REG);
201 	__raw_writeb(0, GDROM_SECNUM_REG);
202 	__raw_writeb(0, GDROM_ERROR_REG);
203 	/* Wait until we can go */
204 	if (!gdrom_wait_clrbusy()) {
205 		gdrom_getsense(NULL);
206 		return;
207 	}
208 	timeout = jiffies + GDROM_DEFAULT_TIMEOUT;
209 	__raw_writeb(GDROM_COM_PACKET, GDROM_STATUSCOMMAND_REG);
210 	while (!gdrom_data_request() && time_before(jiffies, timeout))
211 		cpu_relax();
212 	if (!time_before(jiffies, timeout + 1)) {
213 		gdrom_getsense(NULL);
214 		return;
215 	}
216 	outsw(GDROM_DATA_REG, cmd, 6);
217 }
218 
219 
220 /* gdrom_command_executediagnostic:
221  * Used to probe for presence of working GDROM
222  * Restarts GDROM device and then applies standard ATA 3
223  * Execute Diagnostic Command: a return of '1' indicates device 0
224  * present and device 1 absent
225  */
226 static char gdrom_execute_diagnostic(void)
227 {
228 	gdrom_hardreset(gd.cd_info);
229 	if (!gdrom_wait_clrbusy())
230 		return 0;
231 	__raw_writeb(GDROM_COM_EXECDIAG, GDROM_STATUSCOMMAND_REG);
232 	if (!gdrom_wait_busy_sleeps())
233 		return 0;
234 	return __raw_readb(GDROM_ERROR_REG);
235 }
236 
237 /*
238  * Prepare disk command
239  * byte 0 = 0x70
240  * byte 1 = 0x1f
241  */
242 static int gdrom_preparedisk_cmd(void)
243 {
244 	struct packet_command *spin_command;
245 	spin_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
246 	if (!spin_command)
247 		return -ENOMEM;
248 	spin_command->cmd[0] = 0x70;
249 	spin_command->cmd[2] = 0x1f;
250 	spin_command->buflen = 0;
251 	gd.pending = 1;
252 	gdrom_packetcommand(gd.cd_info, spin_command);
253 	/* 60 second timeout */
254 	wait_event_interruptible_timeout(command_queue, gd.pending == 0,
255 		GDROM_DEFAULT_TIMEOUT);
256 	gd.pending = 0;
257 	kfree(spin_command);
258 	if (gd.status & 0x01) {
259 		/* log an error */
260 		gdrom_getsense(NULL);
261 		return -EIO;
262 	}
263 	return 0;
264 }
265 
266 /*
267  * Read TOC command
268  * byte 0 = 0x14
269  * byte 1 = session
270  * byte 3 = sizeof TOC >> 8  ie upper byte
271  * byte 4 = sizeof TOC & 0xff ie lower byte
272  */
273 static int gdrom_readtoc_cmd(struct gdromtoc *toc, int session)
274 {
275 	int tocsize;
276 	struct packet_command *toc_command;
277 	int err = 0;
278 
279 	toc_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
280 	if (!toc_command)
281 		return -ENOMEM;
282 	tocsize = sizeof(struct gdromtoc);
283 	toc_command->cmd[0] = 0x14;
284 	toc_command->cmd[1] = session;
285 	toc_command->cmd[3] = tocsize >> 8;
286 	toc_command->cmd[4] = tocsize & 0xff;
287 	toc_command->buflen = tocsize;
288 	if (gd.pending) {
289 		err = -EBUSY;
290 		goto cleanup_readtoc_final;
291 	}
292 	gd.pending = 1;
293 	gdrom_packetcommand(gd.cd_info, toc_command);
294 	wait_event_interruptible_timeout(command_queue, gd.pending == 0,
295 		GDROM_DEFAULT_TIMEOUT);
296 	if (gd.pending) {
297 		err = -EINVAL;
298 		goto cleanup_readtoc;
299 	}
300 	insw(GDROM_DATA_REG, toc, tocsize/2);
301 	if (gd.status & 0x01)
302 		err = -EINVAL;
303 
304 cleanup_readtoc:
305 	gd.pending = 0;
306 cleanup_readtoc_final:
307 	kfree(toc_command);
308 	return err;
309 }
310 
311 /* TOC helpers */
312 static int get_entry_lba(int track)
313 {
314 	return (cpu_to_be32(track & 0xffffff00) - GD_SESSION_OFFSET);
315 }
316 
317 static int get_entry_q_ctrl(int track)
318 {
319 	return (track & 0x000000f0) >> 4;
320 }
321 
322 static int get_entry_track(int track)
323 {
324 	return (track & 0x0000ff00) >> 8;
325 }
326 
327 static int gdrom_get_last_session(struct cdrom_device_info *cd_info,
328 	struct cdrom_multisession *ms_info)
329 {
330 	int fentry, lentry, track, data, err;
331 
332 	if (!gd.toc)
333 		return -ENOMEM;
334 
335 	/* Check if GD-ROM */
336 	err = gdrom_readtoc_cmd(gd.toc, 1);
337 	/* Not a GD-ROM so check if standard CD-ROM */
338 	if (err) {
339 		err = gdrom_readtoc_cmd(gd.toc, 0);
340 		if (err) {
341 			pr_info("Could not get CD table of contents\n");
342 			return -ENXIO;
343 		}
344 	}
345 
346 	fentry = get_entry_track(gd.toc->first);
347 	lentry = get_entry_track(gd.toc->last);
348 	/* Find the first data track */
349 	track = get_entry_track(gd.toc->last);
350 	do {
351 		data = gd.toc->entry[track - 1];
352 		if (get_entry_q_ctrl(data))
353 			break;	/* ie a real data track */
354 		track--;
355 	} while (track >= fentry);
356 
357 	if ((track > 100) || (track < get_entry_track(gd.toc->first))) {
358 		pr_info("No data on the last session of the CD\n");
359 		gdrom_getsense(NULL);
360 		return -ENXIO;
361 	}
362 
363 	ms_info->addr_format = CDROM_LBA;
364 	ms_info->addr.lba = get_entry_lba(data);
365 	ms_info->xa_flag = 1;
366 	return 0;
367 }
368 
369 static int gdrom_open(struct cdrom_device_info *cd_info, int purpose)
370 {
371 	/* spin up the disk */
372 	return gdrom_preparedisk_cmd();
373 }
374 
375 /* this function is required even if empty */
376 static void gdrom_release(struct cdrom_device_info *cd_info)
377 {
378 }
379 
380 static int gdrom_drivestatus(struct cdrom_device_info *cd_info, int ignore)
381 {
382 	/* read the sense key */
383 	char sense = __raw_readb(GDROM_ERROR_REG);
384 	sense &= 0xF0;
385 	if (sense == 0)
386 		return CDS_DISC_OK;
387 	if (sense == 0x20)
388 		return CDS_DRIVE_NOT_READY;
389 	/* default */
390 	return CDS_NO_INFO;
391 }
392 
393 static unsigned int gdrom_check_events(struct cdrom_device_info *cd_info,
394 				       unsigned int clearing, int ignore)
395 {
396 	/* check the sense key */
397 	return (__raw_readb(GDROM_ERROR_REG) & 0xF0) == 0x60 ?
398 		DISK_EVENT_MEDIA_CHANGE : 0;
399 }
400 
401 /* reset the G1 bus */
402 static int gdrom_hardreset(struct cdrom_device_info *cd_info)
403 {
404 	int count;
405 	__raw_writel(0x1fffff, GDROM_RESET_REG);
406 	for (count = 0xa0000000; count < 0xa0200000; count += 4)
407 		__raw_readl(count);
408 	return 0;
409 }
410 
411 /* keep the function looking like the universal
412  * CD Rom specification  - returning int */
413 static int gdrom_packetcommand(struct cdrom_device_info *cd_info,
414 	struct packet_command *command)
415 {
416 	gdrom_spicommand(&command->cmd, command->buflen);
417 	return 0;
418 }
419 
420 /* Get Sense SPI command
421  * From Marcus Comstedt
422  * cmd = 0x13
423  * cmd + 4 = length of returned buffer
424  * Returns 5 16 bit words
425  */
426 static int gdrom_getsense(short *bufstring)
427 {
428 	struct packet_command *sense_command;
429 	short sense[5];
430 	int sense_key;
431 	int err = -EIO;
432 
433 	sense_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
434 	if (!sense_command)
435 		return -ENOMEM;
436 	sense_command->cmd[0] = 0x13;
437 	sense_command->cmd[4] = 10;
438 	sense_command->buflen = 10;
439 	/* even if something is pending try to get
440 	* the sense key if possible */
441 	if (gd.pending && !gdrom_wait_clrbusy()) {
442 		err = -EBUSY;
443 		goto cleanup_sense_final;
444 	}
445 	gd.pending = 1;
446 	gdrom_packetcommand(gd.cd_info, sense_command);
447 	wait_event_interruptible_timeout(command_queue, gd.pending == 0,
448 		GDROM_DEFAULT_TIMEOUT);
449 	if (gd.pending)
450 		goto cleanup_sense;
451 	insw(GDROM_DATA_REG, &sense, sense_command->buflen/2);
452 	if (sense[1] & 40) {
453 		pr_info("Drive not ready - command aborted\n");
454 		goto cleanup_sense;
455 	}
456 	sense_key = sense[1] & 0x0F;
457 	if (sense_key < ARRAY_SIZE(sense_texts))
458 		pr_info("%s\n", sense_texts[sense_key].text);
459 	else
460 		pr_err("Unknown sense key: %d\n", sense_key);
461 	if (bufstring) /* return addional sense data */
462 		memcpy(bufstring, &sense[4], 2);
463 	if (sense_key < 2)
464 		err = 0;
465 
466 cleanup_sense:
467 	gd.pending = 0;
468 cleanup_sense_final:
469 	kfree(sense_command);
470 	return err;
471 }
472 
473 static int gdrom_audio_ioctl(struct cdrom_device_info *cdi, unsigned int cmd,
474 			     void *arg)
475 {
476 	return -EINVAL;
477 }
478 
479 static const struct cdrom_device_ops gdrom_ops = {
480 	.open			= gdrom_open,
481 	.release		= gdrom_release,
482 	.drive_status		= gdrom_drivestatus,
483 	.check_events		= gdrom_check_events,
484 	.get_last_session	= gdrom_get_last_session,
485 	.reset			= gdrom_hardreset,
486 	.audio_ioctl		= gdrom_audio_ioctl,
487 	.generic_packet		= cdrom_dummy_generic_packet,
488 	.capability		= CDC_MULTI_SESSION | CDC_MEDIA_CHANGED |
489 				  CDC_RESET | CDC_DRIVE_STATUS | CDC_CD_R,
490 };
491 
492 static int gdrom_bdops_open(struct block_device *bdev, fmode_t mode)
493 {
494 	int ret;
495 
496 	check_disk_change(bdev);
497 
498 	mutex_lock(&gdrom_mutex);
499 	ret = cdrom_open(gd.cd_info, bdev, mode);
500 	mutex_unlock(&gdrom_mutex);
501 	return ret;
502 }
503 
504 static void gdrom_bdops_release(struct gendisk *disk, fmode_t mode)
505 {
506 	mutex_lock(&gdrom_mutex);
507 	cdrom_release(gd.cd_info, mode);
508 	mutex_unlock(&gdrom_mutex);
509 }
510 
511 static unsigned int gdrom_bdops_check_events(struct gendisk *disk,
512 					     unsigned int clearing)
513 {
514 	return cdrom_check_events(gd.cd_info, clearing);
515 }
516 
517 static int gdrom_bdops_ioctl(struct block_device *bdev, fmode_t mode,
518 	unsigned cmd, unsigned long arg)
519 {
520 	int ret;
521 
522 	mutex_lock(&gdrom_mutex);
523 	ret = cdrom_ioctl(gd.cd_info, bdev, mode, cmd, arg);
524 	mutex_unlock(&gdrom_mutex);
525 
526 	return ret;
527 }
528 
529 static const struct block_device_operations gdrom_bdops = {
530 	.owner			= THIS_MODULE,
531 	.open			= gdrom_bdops_open,
532 	.release		= gdrom_bdops_release,
533 	.check_events		= gdrom_bdops_check_events,
534 	.ioctl			= gdrom_bdops_ioctl,
535 };
536 
537 static irqreturn_t gdrom_command_interrupt(int irq, void *dev_id)
538 {
539 	gd.status = __raw_readb(GDROM_STATUSCOMMAND_REG);
540 	if (gd.pending != 1)
541 		return IRQ_HANDLED;
542 	gd.pending = 0;
543 	wake_up_interruptible(&command_queue);
544 	return IRQ_HANDLED;
545 }
546 
547 static irqreturn_t gdrom_dma_interrupt(int irq, void *dev_id)
548 {
549 	gd.status = __raw_readb(GDROM_STATUSCOMMAND_REG);
550 	if (gd.transfer != 1)
551 		return IRQ_HANDLED;
552 	gd.transfer = 0;
553 	wake_up_interruptible(&request_queue);
554 	return IRQ_HANDLED;
555 }
556 
557 static int gdrom_set_interrupt_handlers(void)
558 {
559 	int err;
560 
561 	err = request_irq(HW_EVENT_GDROM_CMD, gdrom_command_interrupt,
562 		0, "gdrom_command", &gd);
563 	if (err)
564 		return err;
565 	err = request_irq(HW_EVENT_GDROM_DMA, gdrom_dma_interrupt,
566 		0, "gdrom_dma", &gd);
567 	if (err)
568 		free_irq(HW_EVENT_GDROM_CMD, &gd);
569 	return err;
570 }
571 
572 /* Implement DMA read using SPI command
573  * 0 -> 0x30
574  * 1 -> mode
575  * 2 -> block >> 16
576  * 3 -> block >> 8
577  * 4 -> block
578  * 8 -> sectors >> 16
579  * 9 -> sectors >> 8
580  * 10 -> sectors
581  */
582 static blk_status_t gdrom_readdisk_dma(struct request *req)
583 {
584 	int block, block_cnt;
585 	blk_status_t err;
586 	struct packet_command *read_command;
587 	unsigned long timeout;
588 
589 	read_command = kzalloc(sizeof(struct packet_command), GFP_KERNEL);
590 	if (!read_command)
591 		return BLK_STS_RESOURCE;
592 
593 	read_command->cmd[0] = 0x30;
594 	read_command->cmd[1] = 0x20;
595 	block = blk_rq_pos(req)/GD_TO_BLK + GD_SESSION_OFFSET;
596 	block_cnt = blk_rq_sectors(req)/GD_TO_BLK;
597 	__raw_writel(virt_to_phys(bio_data(req->bio)), GDROM_DMA_STARTADDR_REG);
598 	__raw_writel(block_cnt * GDROM_HARD_SECTOR, GDROM_DMA_LENGTH_REG);
599 	__raw_writel(1, GDROM_DMA_DIRECTION_REG);
600 	__raw_writel(1, GDROM_DMA_ENABLE_REG);
601 	read_command->cmd[2] = (block >> 16) & 0xFF;
602 	read_command->cmd[3] = (block >> 8) & 0xFF;
603 	read_command->cmd[4] = block & 0xFF;
604 	read_command->cmd[8] = (block_cnt >> 16) & 0xFF;
605 	read_command->cmd[9] = (block_cnt >> 8) & 0xFF;
606 	read_command->cmd[10] = block_cnt & 0xFF;
607 	/* set for DMA */
608 	__raw_writeb(1, GDROM_ERROR_REG);
609 	/* other registers */
610 	__raw_writeb(0, GDROM_SECNUM_REG);
611 	__raw_writeb(0, GDROM_BCL_REG);
612 	__raw_writeb(0, GDROM_BCH_REG);
613 	__raw_writeb(0, GDROM_DSEL_REG);
614 	__raw_writeb(0, GDROM_INTSEC_REG);
615 	/* Wait for registers to reset after any previous activity */
616 	timeout = jiffies + HZ / 2;
617 	while (gdrom_is_busy() && time_before(jiffies, timeout))
618 		cpu_relax();
619 	__raw_writeb(GDROM_COM_PACKET, GDROM_STATUSCOMMAND_REG);
620 	timeout = jiffies + HZ / 2;
621 	/* Wait for packet command to finish */
622 	while (gdrom_is_busy() && time_before(jiffies, timeout))
623 		cpu_relax();
624 	gd.pending = 1;
625 	gd.transfer = 1;
626 	outsw(GDROM_DATA_REG, &read_command->cmd, 6);
627 	timeout = jiffies + HZ / 2;
628 	/* Wait for any pending DMA to finish */
629 	while (__raw_readb(GDROM_DMA_STATUS_REG) &&
630 		time_before(jiffies, timeout))
631 		cpu_relax();
632 	/* start transfer */
633 	__raw_writeb(1, GDROM_DMA_STATUS_REG);
634 	wait_event_interruptible_timeout(request_queue,
635 		gd.transfer == 0, GDROM_DEFAULT_TIMEOUT);
636 	err = gd.transfer ? BLK_STS_IOERR : BLK_STS_OK;
637 	gd.transfer = 0;
638 	gd.pending = 0;
639 
640 	blk_mq_end_request(req, err);
641 	kfree(read_command);
642 	return BLK_STS_OK;
643 }
644 
645 static blk_status_t gdrom_queue_rq(struct blk_mq_hw_ctx *hctx,
646 				   const struct blk_mq_queue_data *bd)
647 {
648 	blk_mq_start_request(bd->rq);
649 
650 	switch (req_op(bd->rq)) {
651 	case REQ_OP_READ:
652 		return gdrom_readdisk_dma(bd->rq);
653 	case REQ_OP_WRITE:
654 		pr_notice("Read only device - write request ignored\n");
655 		return BLK_STS_IOERR;
656 	default:
657 		printk(KERN_DEBUG "gdrom: Non-fs request ignored\n");
658 		return BLK_STS_IOERR;
659 	}
660 }
661 
662 /* Print string identifying GD ROM device */
663 static int gdrom_outputversion(void)
664 {
665 	struct gdrom_id *id;
666 	char *model_name, *manuf_name, *firmw_ver;
667 	int err = -ENOMEM;
668 
669 	/* query device ID */
670 	id = kzalloc(sizeof(struct gdrom_id), GFP_KERNEL);
671 	if (!id)
672 		return err;
673 	gdrom_identifydevice(id);
674 	model_name = kstrndup(id->modname, 16, GFP_KERNEL);
675 	if (!model_name)
676 		goto free_id;
677 	manuf_name = kstrndup(id->mname, 16, GFP_KERNEL);
678 	if (!manuf_name)
679 		goto free_model_name;
680 	firmw_ver = kstrndup(id->firmver, 16, GFP_KERNEL);
681 	if (!firmw_ver)
682 		goto free_manuf_name;
683 	pr_info("%s from %s with firmware %s\n",
684 		model_name, manuf_name, firmw_ver);
685 	err = 0;
686 	kfree(firmw_ver);
687 free_manuf_name:
688 	kfree(manuf_name);
689 free_model_name:
690 	kfree(model_name);
691 free_id:
692 	kfree(id);
693 	return err;
694 }
695 
696 /* set the default mode for DMA transfer */
697 static int gdrom_init_dma_mode(void)
698 {
699 	__raw_writeb(0x13, GDROM_ERROR_REG);
700 	__raw_writeb(0x22, GDROM_INTSEC_REG);
701 	if (!gdrom_wait_clrbusy())
702 		return -EBUSY;
703 	__raw_writeb(0xEF, GDROM_STATUSCOMMAND_REG);
704 	if (!gdrom_wait_busy_sleeps())
705 		return -EBUSY;
706 	/* Memory protection setting for GDROM DMA
707 	* Bits 31 - 16 security: 0x8843
708 	* Bits 15 and 7 reserved (0)
709 	* Bits 14 - 8 start of transfer range in 1 MB blocks OR'ed with 0x80
710 	* Bits 6 - 0 end of transfer range in 1 MB blocks OR'ed with 0x80
711 	* (0x40 | 0x80) = start range at 0x0C000000
712 	* (0x7F | 0x80) = end range at 0x0FFFFFFF */
713 	__raw_writel(0x8843407F, GDROM_DMA_ACCESS_CTRL_REG);
714 	__raw_writel(9, GDROM_DMA_WAIT_REG); /* DMA word setting */
715 	return 0;
716 }
717 
718 static void probe_gdrom_setupcd(void)
719 {
720 	gd.cd_info->ops = &gdrom_ops;
721 	gd.cd_info->capacity = 1;
722 	strcpy(gd.cd_info->name, GDROM_DEV_NAME);
723 	gd.cd_info->mask = CDC_CLOSE_TRAY|CDC_OPEN_TRAY|CDC_LOCK|
724 		CDC_SELECT_DISC;
725 }
726 
727 static void probe_gdrom_setupdisk(void)
728 {
729 	gd.disk->major = gdrom_major;
730 	gd.disk->first_minor = 1;
731 	gd.disk->minors = 1;
732 	strcpy(gd.disk->disk_name, GDROM_DEV_NAME);
733 }
734 
735 static int probe_gdrom_setupqueue(void)
736 {
737 	blk_queue_logical_block_size(gd.gdrom_rq, GDROM_HARD_SECTOR);
738 	/* using DMA so memory will need to be contiguous */
739 	blk_queue_max_segments(gd.gdrom_rq, 1);
740 	/* set a large max size to get most from DMA */
741 	blk_queue_max_segment_size(gd.gdrom_rq, 0x40000);
742 	gd.disk->queue = gd.gdrom_rq;
743 	return gdrom_init_dma_mode();
744 }
745 
746 static const struct blk_mq_ops gdrom_mq_ops = {
747 	.queue_rq	= gdrom_queue_rq,
748 };
749 
750 /*
751  * register this as a block device and as compliant with the
752  * universal CD Rom driver interface
753  */
754 static int probe_gdrom(struct platform_device *devptr)
755 {
756 	int err;
757 	/* Start the device */
758 	if (gdrom_execute_diagnostic() != 1) {
759 		pr_warning("ATA Probe for GDROM failed\n");
760 		return -ENODEV;
761 	}
762 	/* Print out firmware ID */
763 	if (gdrom_outputversion())
764 		return -ENOMEM;
765 	/* Register GDROM */
766 	gdrom_major = register_blkdev(0, GDROM_DEV_NAME);
767 	if (gdrom_major <= 0)
768 		return gdrom_major;
769 	pr_info("Registered with major number %d\n",
770 		gdrom_major);
771 	/* Specify basic properties of drive */
772 	gd.cd_info = kzalloc(sizeof(struct cdrom_device_info), GFP_KERNEL);
773 	if (!gd.cd_info) {
774 		err = -ENOMEM;
775 		goto probe_fail_no_mem;
776 	}
777 	probe_gdrom_setupcd();
778 	gd.disk = alloc_disk(1);
779 	if (!gd.disk) {
780 		err = -ENODEV;
781 		goto probe_fail_no_disk;
782 	}
783 	probe_gdrom_setupdisk();
784 	if (register_cdrom(gd.cd_info)) {
785 		err = -ENODEV;
786 		goto probe_fail_cdrom_register;
787 	}
788 	gd.disk->fops = &gdrom_bdops;
789 	/* latch on to the interrupt */
790 	err = gdrom_set_interrupt_handlers();
791 	if (err)
792 		goto probe_fail_cmdirq_register;
793 
794 	gd.gdrom_rq = blk_mq_init_sq_queue(&gd.tag_set, &gdrom_mq_ops, 1,
795 				BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_BLOCKING);
796 	if (IS_ERR(gd.gdrom_rq)) {
797 		err = PTR_ERR(gd.gdrom_rq);
798 		gd.gdrom_rq = NULL;
799 		goto probe_fail_requestq;
800 	}
801 
802 	blk_queue_bounce_limit(gd.gdrom_rq, BLK_BOUNCE_HIGH);
803 
804 	err = probe_gdrom_setupqueue();
805 	if (err)
806 		goto probe_fail_toc;
807 
808 	gd.toc = kzalloc(sizeof(struct gdromtoc), GFP_KERNEL);
809 	if (!gd.toc) {
810 		err = -ENOMEM;
811 		goto probe_fail_toc;
812 	}
813 	add_disk(gd.disk);
814 	return 0;
815 
816 probe_fail_toc:
817 	blk_cleanup_queue(gd.gdrom_rq);
818 	blk_mq_free_tag_set(&gd.tag_set);
819 probe_fail_requestq:
820 	free_irq(HW_EVENT_GDROM_DMA, &gd);
821 	free_irq(HW_EVENT_GDROM_CMD, &gd);
822 probe_fail_cmdirq_register:
823 probe_fail_cdrom_register:
824 	del_gendisk(gd.disk);
825 probe_fail_no_disk:
826 	kfree(gd.cd_info);
827 probe_fail_no_mem:
828 	unregister_blkdev(gdrom_major, GDROM_DEV_NAME);
829 	gdrom_major = 0;
830 	pr_warning("Probe failed - error is 0x%X\n", err);
831 	return err;
832 }
833 
834 static int remove_gdrom(struct platform_device *devptr)
835 {
836 	blk_cleanup_queue(gd.gdrom_rq);
837 	blk_mq_free_tag_set(&gd.tag_set);
838 	free_irq(HW_EVENT_GDROM_CMD, &gd);
839 	free_irq(HW_EVENT_GDROM_DMA, &gd);
840 	del_gendisk(gd.disk);
841 	if (gdrom_major)
842 		unregister_blkdev(gdrom_major, GDROM_DEV_NAME);
843 	unregister_cdrom(gd.cd_info);
844 
845 	return 0;
846 }
847 
848 static struct platform_driver gdrom_driver = {
849 	.probe = probe_gdrom,
850 	.remove = remove_gdrom,
851 	.driver = {
852 			.name = GDROM_DEV_NAME,
853 	},
854 };
855 
856 static int __init init_gdrom(void)
857 {
858 	int rc;
859 	gd.toc = NULL;
860 	rc = platform_driver_register(&gdrom_driver);
861 	if (rc)
862 		return rc;
863 	pd = platform_device_register_simple(GDROM_DEV_NAME, -1, NULL, 0);
864 	if (IS_ERR(pd)) {
865 		platform_driver_unregister(&gdrom_driver);
866 		return PTR_ERR(pd);
867 	}
868 	return 0;
869 }
870 
871 static void __exit exit_gdrom(void)
872 {
873 	platform_device_unregister(pd);
874 	platform_driver_unregister(&gdrom_driver);
875 	kfree(gd.toc);
876 	kfree(gd.cd_info);
877 }
878 
879 module_init(init_gdrom);
880 module_exit(exit_gdrom);
881 MODULE_AUTHOR("Adrian McMenamin <adrian@mcmen.demon.co.uk>");
882 MODULE_DESCRIPTION("SEGA Dreamcast GD-ROM Driver");
883 MODULE_LICENSE("GPL");
884