aboutsummaryrefslogtreecommitdiff
path: root/payloads/libpayload/drivers/usb/ehci.c
blob: 7ee97612be7cab62cebac7cc11173aaf58d38cd0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
/*
 * This file is part of the libpayload project.
 *
 * Copyright (C) 2010 coresystems GmbH
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <libpayload.h>
#include "ehci.h"
#include "ehci_private.h"

static void dump_td(u32 addr)
{
	qtd_t *td = phys_to_virt(addr);
	debug("td at phys(%x): status: %x\n\n", addr, td->token & QTD_STATUS_MASK);
	debug("-   cerr: %x, total_len: %x\n\n", (td->token & QTD_CERR_MASK) >> QTD_CERR_SHIFT,
		(td->token & QTD_TOTAL_LEN_MASK) >> QTD_TOTAL_LEN_SHIFT);
}

static void ehci_start (hci_t *controller)
{
	EHCI_INST(controller)->operation->usbcmd |= HC_OP_RS;
}

static void ehci_stop (hci_t *controller)
{
	EHCI_INST(controller)->operation->usbcmd &= ~HC_OP_RS;
}

static void ehci_reset (hci_t *controller)
{

}

static int ehci_set_periodic_schedule(ehci_t *ehcic, int enable)
{
	/* Set periodic schedule status. */
	if (enable)
		ehcic->operation->usbcmd |= HC_OP_PERIODIC_SCHED_EN;
	else
		ehcic->operation->usbcmd &= ~HC_OP_PERIODIC_SCHED_EN;
	/* Wait for the controller to accept periodic schedule status.
	 * This shouldn't take too long, but we should timeout nevertheless.
	 */
	enable = enable ? HC_OP_PERIODIC_SCHED_STAT : 0;
	int timeout = 100; /* time out after 100ms */
	while (((ehcic->operation->usbsts & HC_OP_PERIODIC_SCHED_STAT) != enable)
			&& timeout--)
		mdelay(1);
	if (timeout < 0) {
		debug("ehci periodic schedule status change timed out.\n");
		return 1;
	}
	return 0;
}

static void ehci_shutdown (hci_t *controller)
{
	/* Make sure periodic schedule is disabled */
	ehci_set_periodic_schedule(EHCI_INST(controller), 0);
	/* Free periodic frame list */
	free(phys_to_virt(EHCI_INST(controller)->operation->periodiclistbase));

	EHCI_INST(controller)->operation->configflag = 0;
}

enum { EHCI_OUT=0, EHCI_IN=1, EHCI_SETUP=2 };

/*
 * returns the address of the closest USB2.0 hub, which is responsible for
 * split transactions, along with the number of the used downstream port
 */
static int closest_usb2_hub(const usbdev_t *dev, int *const addr, int *const port)
{
	const usbdev_t *usb1dev;
	do {
		usb1dev = dev;
		if ((dev->hub > 0) && (dev->hub < 128))
			dev = dev->controller->devices[dev->hub];
		else
			dev = NULL;
	} while (dev && (dev->speed < 2));
	if (dev) {
		*addr = usb1dev->hub;
		*port = usb1dev->port;
		return 0;
	} else {
		debug("ehci: Couldn't find closest USB2.0 hub.\n");
		return 1;
	}
}

/* returns handled bytes. assumes that the fields it writes are empty on entry */
static int fill_td(qtd_t *td, void* data, int datalen)
{
	u32 total_len = 0;
	u32 page_no = 0;

	u32 start = virt_to_phys(data);
	u32 page = start & ~4095;
	u32 offset = start & 4095;
	u32 page_len = 4096 - offset;

	td->token |= 0 << QTD_CPAGE_SHIFT;
	td->bufptrs[page_no++] = start;

	if (datalen <= page_len) {
		total_len = datalen;
	} else {
		datalen -= page_len;
		total_len += page_len;

		while (page_no < 5) {
			/* we have a continguous mapping between virtual and physical memory */
			page += 4096;

			td->bufptrs[page_no++] = page;
			if (datalen <= 4096) {
				total_len += datalen;
				break;
			}
			datalen -= 4096;
			total_len += 4096;
		}
	}
	td->token |= total_len << QTD_TOTAL_LEN_SHIFT;
	return total_len;
}

/* free up data structures */
static void free_qh_and_tds(ehci_qh_t *qh, qtd_t *cur)
{
	qtd_t *next;
	while (cur) {
		next = (qtd_t*)phys_to_virt(cur->next_qtd & ~31);
		free(cur);
		cur = next;
	}
	free(qh);
}

static int wait_for_tds(qtd_t *head)
{
	int result = 0;
	qtd_t *cur = head;
	while (1) {
		if (0) dump_td(virt_to_phys(cur));
		while ((cur->token & QTD_ACTIVE) && !(cur->token & QTD_HALTED)) udelay(60);
		if (cur->token & QTD_HALTED) {
			printf("ERROR with packet\n");
			dump_td(virt_to_phys(cur));
			debug("-----------------\n");
			return 1;
		}
		if (cur->next_qtd & 1) {
			return 0;
		}
		if (0) dump_td(virt_to_phys(cur));
		/* helps debugging the TD chain */
		if (0) debug("\nmoving from %x to %x\n", cur, phys_to_virt(cur->next_qtd));
		cur = phys_to_virt(cur->next_qtd);
	}
	return result;
}

static int ehci_bulk (endpoint_t *ep, int size, u8 *data, int finalize)
{
	int result = 0;
	int endp = ep->endpoint & 0xf;
	int pid = (ep->direction==IN)?EHCI_IN:EHCI_OUT;

	int hubaddr = 0, hubport = 0;
	if (ep->dev->speed < 2) {
		/* we need a split transaction */
		if (closest_usb2_hub(ep->dev, &hubaddr, &hubport))
			return 1;
	}

	qtd_t *head = memalign(32, sizeof(qtd_t));
	qtd_t *cur = head;
	while (1) {
		memset(cur, 0, sizeof(qtd_t));
		cur->token = QTD_ACTIVE |
			(pid << QTD_PID_SHIFT) |
			(0 << QTD_CERR_SHIFT);
		u32 chunk = fill_td(cur, data, size);
		size -= chunk;
		data += chunk;

		cur->alt_next_qtd = QTD_TERMINATE;
		if (size == 0) {
			cur->next_qtd = virt_to_phys(0) | QTD_TERMINATE;
			break;
		} else {
			qtd_t *next = memalign(32, sizeof(qtd_t));
			cur->next_qtd = virt_to_phys(next);
			cur = next;
		}
	}

	/* create QH */
	ehci_qh_t *qh = memalign(32, sizeof(ehci_qh_t));
	memset(qh, 0, sizeof(ehci_qh_t));
	qh->horiz_link_ptr = virt_to_phys(qh) | QH_QH;
	qh->epchar = ep->dev->address |
		(endp << QH_EP_SHIFT) |
		(ep->dev->speed << QH_EPS_SHIFT) |
		(0 << QH_DTC_SHIFT) |
		(1 << QH_RECLAIM_HEAD_SHIFT) |
		(ep->maxpacketsize << QH_MPS_SHIFT) |
		(0 << QH_NAK_CNT_SHIFT);
	qh->epcaps = (3 << QH_PIPE_MULTIPLIER_SHIFT) |
		(hubport << QH_PORT_NUMBER_SHIFT) |
		(hubaddr << QH_HUB_ADDRESS_SHIFT);

	qh->td.next_qtd = virt_to_phys(head);
	qh->td.token |= (ep->toggle?QTD_TOGGLE_DATA1:0);
	head->token |= (ep->toggle?QTD_TOGGLE_DATA1:0);

	/* hook up QH */
	EHCI_INST(ep->dev->controller)->operation->asynclistaddr = virt_to_phys(qh);

	/* start async schedule */
	EHCI_INST(ep->dev->controller)->operation->usbcmd |= HC_OP_ASYNC_SCHED_EN;
	while (!(EHCI_INST(ep->dev->controller)->operation->usbsts & HC_OP_ASYNC_SCHED_STAT)) ; /* wait */

	/* wait for result */
	result = wait_for_tds(head);

	/* disable async schedule */
	EHCI_INST(ep->dev->controller)->operation->usbcmd &= ~HC_OP_ASYNC_SCHED_EN;
	while (EHCI_INST(ep->dev->controller)->operation->usbsts & HC_OP_ASYNC_SCHED_STAT) ; /* wait */

	ep->toggle = (cur->token & QTD_TOGGLE_MASK) >> QTD_TOGGLE_SHIFT;

	free_qh_and_tds(qh, head);
	return result;
}


/* FIXME: Handle control transfers as 3 QHs, so the 2nd stage can be >0x4000 bytes */
static int ehci_control (usbdev_t *dev, direction_t dir, int drlen, void *devreq,
			 int dalen, u8 *data)
{
	int endp = 0; // this is control. always 0 (for now)
	int toggle = 0;
	int mlen = dev->endpoints[0].maxpacketsize;
	int result = 0;

	int hubaddr = 0, hubport = 0, non_hs_ctrl_ep = 0;
	if (dev->speed < 2) {
		/* we need a split transaction */
		if (closest_usb2_hub(dev, &hubaddr, &hubport))
			return 1;
		non_hs_ctrl_ep = 1;
	}

	/* create qTDs */
	qtd_t *head = memalign(32, sizeof(qtd_t));
	qtd_t *cur = head;
	memset(cur, 0, sizeof(qtd_t));
	cur->token = QTD_ACTIVE |
		(toggle?QTD_TOGGLE_DATA1:0) |
		(EHCI_SETUP << QTD_PID_SHIFT) |
		(3 << QTD_CERR_SHIFT);
	if (fill_td(cur, devreq, drlen) != drlen) {
		printf("ERROR: couldn't send the entire device request\n");
	}
	qtd_t *next = memalign(32, sizeof(qtd_t));
	cur->next_qtd = virt_to_phys(next);
	cur->alt_next_qtd = QTD_TERMINATE;

	/* FIXME: We're limited to 16-20K (depending on alignment) for payload for now.
	 * Figure out, how toggle can be set sensibly in this scenario */
	if (dalen > 0) {
		toggle ^= 1;
		cur = next;
		memset(cur, 0, sizeof(qtd_t));
		cur->token = QTD_ACTIVE |
			(toggle?QTD_TOGGLE_DATA1:0) |
			(((dir == OUT)?EHCI_OUT:EHCI_IN) << QTD_PID_SHIFT) |
			(3 << QTD_CERR_SHIFT);
		if (fill_td(cur, data, dalen) != dalen) {
			printf("ERROR: couldn't send the entire control payload\n");
		}
		next = memalign(32, sizeof(qtd_t));
		cur->next_qtd = virt_to_phys(next);
		cur->alt_next_qtd = QTD_TERMINATE;
	}

	toggle = 1;
	cur = next;
	memset(cur, 0, sizeof(qtd_t));
	cur->token = QTD_ACTIVE |
		(toggle?QTD_TOGGLE_DATA1:QTD_TOGGLE_DATA0) |
		((dir == OUT)?EHCI_IN:EHCI_OUT) << QTD_PID_SHIFT |
		(0 << QTD_CERR_SHIFT);
	fill_td(cur, NULL, 0);
	cur->next_qtd = virt_to_phys(0) | QTD_TERMINATE;
	cur->alt_next_qtd = QTD_TERMINATE;

	/* create QH */
	ehci_qh_t *qh = memalign(32, sizeof(ehci_qh_t));
	memset(qh, 0, sizeof(ehci_qh_t));
	qh->horiz_link_ptr = virt_to_phys(qh) | QH_QH;
	qh->epchar = dev->address |
		(endp << QH_EP_SHIFT) |
		(dev->speed << QH_EPS_SHIFT) |
		(1 << QH_DTC_SHIFT) | /* ctrl transfers are special: take toggle bit from TD */
		(1 << QH_RECLAIM_HEAD_SHIFT) |
		(mlen << QH_MPS_SHIFT) |
		(non_hs_ctrl_ep << QH_NON_HS_CTRL_EP_SHIFT) |
		(0 << QH_NAK_CNT_SHIFT);
	qh->epcaps = (3 << QH_PIPE_MULTIPLIER_SHIFT) |
		(hubport << QH_PORT_NUMBER_SHIFT) |
		(hubaddr << QH_HUB_ADDRESS_SHIFT);
	qh->td.next_qtd = virt_to_phys(head);

	/* hook up QH */
	EHCI_INST(dev->controller)->operation->asynclistaddr = virt_to_phys(qh);

	/* start async schedule */
	EHCI_INST(dev->controller)->operation->usbcmd |= HC_OP_ASYNC_SCHED_EN;
	while (!(EHCI_INST(dev->controller)->operation->usbsts & HC_OP_ASYNC_SCHED_STAT)) ; /* wait */

	result = wait_for_tds(head);

	/* disable async schedule */
	EHCI_INST(dev->controller)->operation->usbcmd &= ~HC_OP_ASYNC_SCHED_EN;
	while (EHCI_INST(dev->controller)->operation->usbsts & HC_OP_ASYNC_SCHED_STAT) ; /* wait */

	free_qh_and_tds(qh, head);
	return result;
}


typedef struct _intr_qtd_t intr_qtd_t;

struct _intr_qtd_t {
	volatile qtd_t	td;
	u8		*data;
	intr_qtd_t	*next;
};

typedef struct {
	volatile ehci_qh_t	qh;
	intr_qtd_t		*head;
	intr_qtd_t		*tail;
	u8			*data;
	endpoint_t		*endp;
	int			reqsize;
} intr_queue_t;

static void fill_intr_queue_td(
		intr_queue_t *const intrq,
		intr_qtd_t *const intr_qtd,
		u8 *const data)
{
	const int pid = (intrq->endp->direction == IN) ? EHCI_IN
		: (intrq->endp->direction == OUT) ? EHCI_OUT
		: EHCI_SETUP;
	const int cerr = (intrq->endp->dev->speed < 2) ? 1 : 0;

	memset(intr_qtd, 0, sizeof(*intr_qtd));
	intr_qtd->td.next_qtd = QTD_TERMINATE;
	intr_qtd->td.alt_next_qtd = QTD_TERMINATE;
	intr_qtd->td.token = QTD_ACTIVE |
		(pid << QTD_PID_SHIFT) |
		(cerr << QTD_CERR_SHIFT) |
		((intrq->endp->toggle & 1) << QTD_TOGGLE_SHIFT);
	fill_td(&intr_qtd->td, data, intrq->reqsize);
	intr_qtd->data = data;
	intr_qtd->next = NULL;

	intrq->endp->toggle ^= 1;
}

static void ehci_destroy_intr_queue(endpoint_t *const, void *const);

static void *ehci_create_intr_queue(
		endpoint_t *const ep,
		const int reqsize,
		int reqcount,
		const int reqtiming)
{
	int i;

	if ((reqsize > (4 * 4096 + 1)) || /* the maximum for arbitrary aligned
					     data in five 4096 byte pages */
			(reqtiming > 1024))
		return NULL;
	if (reqcount < 2) /* we need at least 2:
			     one for processing, one for the hc to advance to */
		reqcount = 2;

	int hubaddr = 0, hubport = 0;
	if (ep->dev->speed < 2) {
		/* we need a split transaction */
		if (closest_usb2_hub(ep->dev, &hubaddr, &hubport))
			return NULL;
	}

	intr_queue_t *const intrq =
		(intr_queue_t *)memalign(32, sizeof(intr_queue_t));
	u8 *data = (u8 *)malloc(reqsize * reqcount);
	if (!intrq || !data)
		fatal("Not enough memory to create USB interrupt queue.\n");
	intrq->data = data;
	intrq->endp = ep;
	intrq->reqsize = reqsize;

	/* create #reqcount transfer descriptors (qTDs) */
	intrq->head = (intr_qtd_t *)memalign(32, sizeof(intr_qtd_t));
	intr_qtd_t *cur_td = intrq->head;
	for (i = 0; i < reqcount; ++i) {
		fill_intr_queue_td(intrq, cur_td, data);
		data += reqsize;
		if (i < reqcount - 1) {
			/* create one more qTD */
			intr_qtd_t *const next_td =
				(intr_qtd_t *)memalign(32, sizeof(intr_qtd_t));
			cur_td->td.next_qtd = virt_to_phys(&next_td->td);
			cur_td->next = next_td;
			cur_td = next_td;
		}
	}
	intrq->tail = cur_td;

	/* initialize QH */
	const int endp = ep->endpoint & 0xf;
	memset(&intrq->qh, 0, sizeof(intrq->qh));
	intrq->qh.horiz_link_ptr = PS_TERMINATE;
	intrq->qh.epchar = ep->dev->address |
		(endp << QH_EP_SHIFT) |
		(ep->dev->speed << QH_EPS_SHIFT) |
		(1 << QH_DTC_SHIFT) |
		(0 << QH_RECLAIM_HEAD_SHIFT) |
		(ep->maxpacketsize << QH_MPS_SHIFT) |
		(0 << QH_NAK_CNT_SHIFT);
	intrq->qh.epcaps = (1 << QH_PIPE_MULTIPLIER_SHIFT) |
		(hubport << QH_PORT_NUMBER_SHIFT) |
		(hubaddr << QH_HUB_ADDRESS_SHIFT) |
		(0xfe << QH_UFRAME_CMASK_SHIFT) |
		1 /* uFrame S-mask */;
	intrq->qh.td.next_qtd = virt_to_phys(&intrq->head->td);

	/* insert QH into periodic schedule */
	int nothing_placed = 1;
	u32 *const ps = (u32 *)phys_to_virt(EHCI_INST(ep->dev->controller)
						->operation->periodiclistbase);
	for (i = 0; i < 1024; i += reqtiming) {
		/* advance to the next free position */
		while ((i < 1024) && !(ps[i] & PS_TERMINATE)) ++i;
		if (i < 1024) {
			ps[i] =	virt_to_phys(&intrq->qh) | PS_TYPE_QH;
			nothing_placed = 0;
		}
	}
	if (nothing_placed) {
		printf("Error: Failed to place ehci interrupt queue head "
				"into periodic schedule: no space left\n");
		ehci_destroy_intr_queue(ep, intrq);
		return NULL;
	}

	return intrq;
}

static void ehci_destroy_intr_queue(endpoint_t *const ep, void *const queue)
{
	intr_queue_t *const intrq = (intr_queue_t *)queue;

	/* remove QH from periodic schedule */
	int i;
	u32 *const ps = (u32 *)phys_to_virt(EHCI_INST(
			ep->dev->controller)->operation->periodiclistbase);
	for (i = 0; i < 1024; ++i) {
		if ((ps[i] & PS_PTR_MASK) == virt_to_phys(&intrq->qh))
			ps[i] = PS_TERMINATE;
	}

	/* wait 1ms for frame to end */
	mdelay(1);

	while (intrq->head) {
		/* disable qTD and destroy list */
		intrq->head->td.next_qtd = QTD_TERMINATE;
		intrq->head->td.token &= ~QTD_ACTIVE;

		/* save and advance head ptr */
		intr_qtd_t *const to_free = intrq->head;
		intrq->head = intrq->head->next;

		/* free current interrupt qTD */
		free(to_free);
	}
	free(intrq->data);
	free(intrq);
}

static u8 *ehci_poll_intr_queue(void *const queue)
{
	intr_queue_t *const intrq = (intr_queue_t *)queue;

	u8 *ret = NULL;

	/* process if head qTD is inactive AND QH has been moved forward */
	if (!(intrq->head->td.token & QTD_ACTIVE) &&
			(intrq->qh.current_td_ptr !=
			 virt_to_phys(&intrq->head->td))) {
		if (!(intrq->head->td.token & QTD_STATUS_MASK))
			ret = intrq->head->data;
		else
			debug("ehci_poll_intr_queue: transfer failed, "
				"status == 0x%02x\n",
				intrq->head->td.token & QTD_STATUS_MASK);

		/* save and advance our head ptr */
		intr_qtd_t *const new_td = intrq->head;
		intrq->head = intrq->head->next;

		/* reuse executed qTD */
		fill_intr_queue_td(intrq, new_td, new_td->data);

		/* at last insert reused qTD at the
		 * end and advance our tail ptr */
		intrq->tail->td.next_qtd = virt_to_phys(&new_td->td);
		intrq->tail->next = new_td;
		intrq->tail = intrq->tail->next;
	}
	return ret;
}

hci_t *
ehci_init (pcidev_t addr)
{
	int i;
	hci_t *controller = new_controller ();

	if (!controller)
		fatal("Could not create USB controller instance.\n");

	controller->instance = malloc (sizeof (ehci_t));
	if(!controller->instance)
		fatal("Not enough memory creating USB controller instance.\n");

#define PCI_COMMAND 4
#define PCI_COMMAND_IO 1
#define PCI_COMMAND_MEMORY 2
#define PCI_COMMAND_MASTER 4

	u32 pci_command = pci_read_config32(addr, PCI_COMMAND);
	pci_command = (pci_command | PCI_COMMAND_MEMORY) & ~PCI_COMMAND_IO ;
	pci_write_config32(addr, PCI_COMMAND, pci_command);

	controller->start = ehci_start;
	controller->stop = ehci_stop;
	controller->reset = ehci_reset;
	controller->shutdown = ehci_shutdown;
	controller->bulk = ehci_bulk;
	controller->control = ehci_control;
	controller->create_intr_queue = ehci_create_intr_queue;
	controller->destroy_intr_queue = ehci_destroy_intr_queue;
	controller->poll_intr_queue = ehci_poll_intr_queue;
	controller->bus_address = addr;
	for (i = 0; i < 128; i++) {
		controller->devices[i] = 0;
	}
	init_device_entry (controller, 0);

	EHCI_INST(controller)->capabilities = phys_to_virt(pci_read_config32(addr, USBBASE));
	EHCI_INST(controller)->operation = (hc_op_t *)(phys_to_virt(pci_read_config32(addr, USBBASE)) + EHCI_INST(controller)->capabilities->caplength);

	/* default value for frame length adjust */
	pci_write_config8(addr, FLADJ, FLADJ_framelength(60000));

	/* Enable operation of controller */
	controller->start(controller);

	/* take over all ports. USB1 should be blind now */
	EHCI_INST(controller)->operation->configflag = 1;

	/* Initialize periodic frame list */
	/* 1024 32-bit pointers, 4kb aligned */
	u32 *const periodic_list = (u32 *)memalign(4096, 1024 * sizeof(u32));
	if (!periodic_list)
		fatal("Not enough memory creating EHCI periodic frame list.\n");
	for (i = 0; i < 1024; ++i)
		periodic_list[i] = PS_TERMINATE;

	/* Make sure periodic schedule is disabled */
	ehci_set_periodic_schedule(EHCI_INST(controller), 0);
	/* Set periodic frame list pointer */
	EHCI_INST(controller)->operation->periodiclistbase =
		virt_to_phys(periodic_list);
	/* Enable use of periodic schedule */
	ehci_set_periodic_schedule(EHCI_INST(controller), 1);

	/* TODO lots of stuff missing */

	controller->devices[0]->controller = controller;
	controller->devices[0]->init = ehci_rh_init;
	controller->devices[0]->init (controller->devices[0]);

	return controller;
}