blob: 9b13bf2fa98d2c3bab626642a1ea925e183ed9e9 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
David Brownelld49d4312005-05-07 13:21:50 -07002 * Copyright (C) 2001-2004 by David Brownell
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License as published by the
6 * Free Software Foundation; either version 2 of the License, or (at your
7 * option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
11 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software Foundation,
16 * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
17 */
18
19/* this file is part of ehci-hcd.c */
20
21/*-------------------------------------------------------------------------*/
22
23/*
24 * EHCI hardware queue manipulation ... the core. QH/QTD manipulation.
25 *
26 * Control, bulk, and interrupt traffic all use "qh" lists. They list "qtd"
27 * entries describing USB transactions, max 16-20kB/entry (with 4kB-aligned
28 * buffers needed for the larger number). We use one QH per endpoint, queue
29 * multiple urbs (all three types) per endpoint. URBs may need several qtds.
30 *
31 * ISO traffic uses "ISO TD" (itd, and sitd) records, and (along with
32 * interrupts) needs careful scheduling. Performance improvements can be
33 * an ongoing challenge. That's in "ehci-sched.c".
34 *
35 * USB 1.1 devices are handled (a) by "companion" OHCI or UHCI root hubs,
36 * or otherwise through transaction translators (TTs) in USB 2.0 hubs using
37 * (b) special fields in qh entries or (c) split iso entries. TTs will
38 * buffer low/full speed data so the host collects it at high speed.
39 */
40
41/*-------------------------------------------------------------------------*/
42
43/* fill a qtd, returning how much of the buffer we were able to queue up */
44
45static int
46qtd_fill (struct ehci_qtd *qtd, dma_addr_t buf, size_t len,
47 int token, int maxpacket)
48{
49 int i, count;
50 u64 addr = buf;
51
52 /* one buffer entry per 4K ... first might be short or unaligned */
53 qtd->hw_buf [0] = cpu_to_le32 ((u32)addr);
54 qtd->hw_buf_hi [0] = cpu_to_le32 ((u32)(addr >> 32));
55 count = 0x1000 - (buf & 0x0fff); /* rest of that page */
56 if (likely (len < count)) /* ... iff needed */
57 count = len;
58 else {
59 buf += 0x1000;
60 buf &= ~0x0fff;
61
62 /* per-qtd limit: from 16K to 20K (best alignment) */
63 for (i = 1; count < len && i < 5; i++) {
64 addr = buf;
65 qtd->hw_buf [i] = cpu_to_le32 ((u32)addr);
66 qtd->hw_buf_hi [i] = cpu_to_le32 ((u32)(addr >> 32));
67 buf += 0x1000;
68 if ((count + 0x1000) < len)
69 count += 0x1000;
70 else
71 count = len;
72 }
73
74 /* short packets may only terminate transfers */
75 if (count != len)
76 count -= (count % maxpacket);
77 }
78 qtd->hw_token = cpu_to_le32 ((count << 16) | token);
79 qtd->length = count;
80
81 return count;
82}
83
84/*-------------------------------------------------------------------------*/
85
86static inline void
87qh_update (struct ehci_hcd *ehci, struct ehci_qh *qh, struct ehci_qtd *qtd)
88{
89 /* writes to an active overlay are unsafe */
90 BUG_ON(qh->qh_state != QH_STATE_IDLE);
91
92 qh->hw_qtd_next = QTD_NEXT (qtd->qtd_dma);
93 qh->hw_alt_next = EHCI_LIST_END;
94
95 /* Except for control endpoints, we make hardware maintain data
96 * toggle (like OHCI) ... here (re)initialize the toggle in the QH,
97 * and set the pseudo-toggle in udev. Only usb_clear_halt() will
98 * ever clear it.
99 */
100 if (!(qh->hw_info1 & cpu_to_le32(1 << 14))) {
101 unsigned is_out, epnum;
102
103 is_out = !(qtd->hw_token & cpu_to_le32(1 << 8));
104 epnum = (le32_to_cpup(&qh->hw_info1) >> 8) & 0x0f;
105 if (unlikely (!usb_gettoggle (qh->dev, epnum, is_out))) {
106 qh->hw_token &= ~__constant_cpu_to_le32 (QTD_TOGGLE);
107 usb_settoggle (qh->dev, epnum, is_out, 1);
108 }
109 }
110
111 /* HC must see latest qtd and qh data before we clear ACTIVE+HALT */
112 wmb ();
113 qh->hw_token &= __constant_cpu_to_le32 (QTD_TOGGLE | QTD_STS_PING);
114}
115
116/* if it weren't for a common silicon quirk (writing the dummy into the qh
117 * overlay, so qh->hw_token wrongly becomes inactive/halted), only fault
118 * recovery (including urb dequeue) would need software changes to a QH...
119 */
120static void
121qh_refresh (struct ehci_hcd *ehci, struct ehci_qh *qh)
122{
123 struct ehci_qtd *qtd;
124
125 if (list_empty (&qh->qtd_list))
126 qtd = qh->dummy;
127 else {
128 qtd = list_entry (qh->qtd_list.next,
129 struct ehci_qtd, qtd_list);
130 /* first qtd may already be partially processed */
131 if (cpu_to_le32 (qtd->qtd_dma) == qh->hw_current)
132 qtd = NULL;
133 }
134
135 if (qtd)
136 qh_update (ehci, qh, qtd);
137}
138
139/*-------------------------------------------------------------------------*/
140
141static void qtd_copy_status (
142 struct ehci_hcd *ehci,
143 struct urb *urb,
144 size_t length,
145 u32 token
146)
147{
148 /* count IN/OUT bytes, not SETUP (even short packets) */
149 if (likely (QTD_PID (token) != 2))
150 urb->actual_length += length - QTD_LENGTH (token);
151
152 /* don't modify error codes */
153 if (unlikely (urb->status != -EINPROGRESS))
154 return;
155
156 /* force cleanup after short read; not always an error */
157 if (unlikely (IS_SHORT_READ (token)))
158 urb->status = -EREMOTEIO;
159
160 /* serious "can't proceed" faults reported by the hardware */
161 if (token & QTD_STS_HALT) {
162 if (token & QTD_STS_BABBLE) {
163 /* FIXME "must" disable babbling device's port too */
164 urb->status = -EOVERFLOW;
165 } else if (token & QTD_STS_MMF) {
166 /* fs/ls interrupt xfer missed the complete-split */
167 urb->status = -EPROTO;
168 } else if (token & QTD_STS_DBE) {
169 urb->status = (QTD_PID (token) == 1) /* IN ? */
170 ? -ENOSR /* hc couldn't read data */
171 : -ECOMM; /* hc couldn't write data */
172 } else if (token & QTD_STS_XACT) {
173 /* timeout, bad crc, wrong PID, etc; retried */
174 if (QTD_CERR (token))
175 urb->status = -EPIPE;
176 else {
177 ehci_dbg (ehci, "devpath %s ep%d%s 3strikes\n",
178 urb->dev->devpath,
179 usb_pipeendpoint (urb->pipe),
180 usb_pipein (urb->pipe) ? "in" : "out");
181 urb->status = -EPROTO;
182 }
183 /* CERR nonzero + no errors + halt --> stall */
184 } else if (QTD_CERR (token))
185 urb->status = -EPIPE;
186 else /* unknown */
187 urb->status = -EPROTO;
188
189 ehci_vdbg (ehci,
190 "dev%d ep%d%s qtd token %08x --> status %d\n",
191 usb_pipedevice (urb->pipe),
192 usb_pipeendpoint (urb->pipe),
193 usb_pipein (urb->pipe) ? "in" : "out",
194 token, urb->status);
195
196 /* if async CSPLIT failed, try cleaning out the TT buffer */
197 if (urb->status != -EPIPE
198 && urb->dev->tt && !usb_pipeint (urb->pipe)
199 && ((token & QTD_STS_MMF) != 0
200 || QTD_CERR(token) == 0)
201 && (!ehci_is_TDI(ehci)
202 || urb->dev->tt->hub !=
203 ehci_to_hcd(ehci)->self.root_hub)) {
204#ifdef DEBUG
205 struct usb_device *tt = urb->dev->tt->hub;
206 dev_dbg (&tt->dev,
207 "clear tt buffer port %d, a%d ep%d t%08x\n",
208 urb->dev->ttport, urb->dev->devnum,
209 usb_pipeendpoint (urb->pipe), token);
210#endif /* DEBUG */
211 usb_hub_tt_clear_buffer (urb->dev, urb->pipe);
212 }
213 }
214}
215
216static void
217ehci_urb_done (struct ehci_hcd *ehci, struct urb *urb, struct pt_regs *regs)
218__releases(ehci->lock)
219__acquires(ehci->lock)
220{
221 if (likely (urb->hcpriv != NULL)) {
222 struct ehci_qh *qh = (struct ehci_qh *) urb->hcpriv;
223
224 /* S-mask in a QH means it's an interrupt urb */
David Brownell7dedacf2005-08-04 18:06:41 -0700225 if ((qh->hw_info2 & __constant_cpu_to_le32 (QH_SMASK)) != 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226
227 /* ... update hc-wide periodic stats (for usbfs) */
228 ehci_to_hcd(ehci)->self.bandwidth_int_reqs--;
229 }
230 qh_put (qh);
231 }
232
233 spin_lock (&urb->lock);
234 urb->hcpriv = NULL;
235 switch (urb->status) {
236 case -EINPROGRESS: /* success */
237 urb->status = 0;
238 default: /* fault */
239 COUNT (ehci->stats.complete);
240 break;
241 case -EREMOTEIO: /* fault or normal */
242 if (!(urb->transfer_flags & URB_SHORT_NOT_OK))
243 urb->status = 0;
244 COUNT (ehci->stats.complete);
245 break;
246 case -ECONNRESET: /* canceled */
247 case -ENOENT:
248 COUNT (ehci->stats.unlink);
249 break;
250 }
251 spin_unlock (&urb->lock);
252
253#ifdef EHCI_URB_TRACE
254 ehci_dbg (ehci,
255 "%s %s urb %p ep%d%s status %d len %d/%d\n",
256 __FUNCTION__, urb->dev->devpath, urb,
257 usb_pipeendpoint (urb->pipe),
258 usb_pipein (urb->pipe) ? "in" : "out",
259 urb->status,
260 urb->actual_length, urb->transfer_buffer_length);
261#endif
262
263 /* complete() can reenter this HCD */
264 spin_unlock (&ehci->lock);
265 usb_hcd_giveback_urb (ehci_to_hcd(ehci), urb, regs);
266 spin_lock (&ehci->lock);
267}
268
269static void start_unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh);
270static void unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh);
271
272static void intr_deschedule (struct ehci_hcd *ehci, struct ehci_qh *qh);
273static int qh_schedule (struct ehci_hcd *ehci, struct ehci_qh *qh);
274
275/*
276 * Process and free completed qtds for a qh, returning URBs to drivers.
277 * Chases up to qh->hw_current. Returns number of completions called,
278 * indicating how much "real" work we did.
279 */
280#define HALT_BIT __constant_cpu_to_le32(QTD_STS_HALT)
281static unsigned
282qh_completions (struct ehci_hcd *ehci, struct ehci_qh *qh, struct pt_regs *regs)
283{
284 struct ehci_qtd *last = NULL, *end = qh->dummy;
285 struct list_head *entry, *tmp;
286 int stopped;
287 unsigned count = 0;
288 int do_status = 0;
289 u8 state;
290
291 if (unlikely (list_empty (&qh->qtd_list)))
292 return count;
293
294 /* completions (or tasks on other cpus) must never clobber HALT
295 * till we've gone through and cleaned everything up, even when
296 * they add urbs to this qh's queue or mark them for unlinking.
297 *
298 * NOTE: unlinking expects to be done in queue order.
299 */
300 state = qh->qh_state;
301 qh->qh_state = QH_STATE_COMPLETING;
302 stopped = (state == QH_STATE_IDLE);
303
304 /* remove de-activated QTDs from front of queue.
305 * after faults (including short reads), cleanup this urb
306 * then let the queue advance.
307 * if queue is stopped, handles unlinks.
308 */
309 list_for_each_safe (entry, tmp, &qh->qtd_list) {
310 struct ehci_qtd *qtd;
311 struct urb *urb;
312 u32 token = 0;
313
314 qtd = list_entry (entry, struct ehci_qtd, qtd_list);
315 urb = qtd->urb;
316
317 /* clean up any state from previous QTD ...*/
318 if (last) {
319 if (likely (last->urb != urb)) {
320 ehci_urb_done (ehci, last->urb, regs);
321 count++;
322 }
323 ehci_qtd_free (ehci, last);
324 last = NULL;
325 }
326
327 /* ignore urbs submitted during completions we reported */
328 if (qtd == end)
329 break;
330
331 /* hardware copies qtd out of qh overlay */
332 rmb ();
333 token = le32_to_cpu (qtd->hw_token);
334
335 /* always clean up qtds the hc de-activated */
336 if ((token & QTD_STS_ACTIVE) == 0) {
337
338 if ((token & QTD_STS_HALT) != 0) {
339 stopped = 1;
340
341 /* magic dummy for some short reads; qh won't advance.
342 * that silicon quirk can kick in with this dummy too.
343 */
344 } else if (IS_SHORT_READ (token)
345 && !(qtd->hw_alt_next & EHCI_LIST_END)) {
346 stopped = 1;
347 goto halt;
348 }
349
350 /* stop scanning when we reach qtds the hc is using */
351 } else if (likely (!stopped
352 && HC_IS_RUNNING (ehci_to_hcd(ehci)->state))) {
353 break;
354
355 } else {
356 stopped = 1;
357
358 if (unlikely (!HC_IS_RUNNING (ehci_to_hcd(ehci)->state)))
359 urb->status = -ESHUTDOWN;
360
361 /* ignore active urbs unless some previous qtd
362 * for the urb faulted (including short read) or
363 * its urb was canceled. we may patch qh or qtds.
364 */
365 if (likely (urb->status == -EINPROGRESS))
366 continue;
367
368 /* issue status after short control reads */
369 if (unlikely (do_status != 0)
370 && QTD_PID (token) == 0 /* OUT */) {
371 do_status = 0;
372 continue;
373 }
374
375 /* token in overlay may be most current */
376 if (state == QH_STATE_IDLE
377 && cpu_to_le32 (qtd->qtd_dma)
378 == qh->hw_current)
379 token = le32_to_cpu (qh->hw_token);
380
381 /* force halt for unlinked or blocked qh, so we'll
382 * patch the qh later and so that completions can't
383 * activate it while we "know" it's stopped.
384 */
385 if ((HALT_BIT & qh->hw_token) == 0) {
386halt:
387 qh->hw_token |= HALT_BIT;
388 wmb ();
389 }
390 }
391
392 /* remove it from the queue */
393 spin_lock (&urb->lock);
394 qtd_copy_status (ehci, urb, qtd->length, token);
395 do_status = (urb->status == -EREMOTEIO)
396 && usb_pipecontrol (urb->pipe);
397 spin_unlock (&urb->lock);
398
399 if (stopped && qtd->qtd_list.prev != &qh->qtd_list) {
400 last = list_entry (qtd->qtd_list.prev,
401 struct ehci_qtd, qtd_list);
402 last->hw_next = qtd->hw_next;
403 }
404 list_del (&qtd->qtd_list);
405 last = qtd;
406 }
407
408 /* last urb's completion might still need calling */
409 if (likely (last != NULL)) {
410 ehci_urb_done (ehci, last->urb, regs);
411 count++;
412 ehci_qtd_free (ehci, last);
413 }
414
415 /* restore original state; caller must unlink or relink */
416 qh->qh_state = state;
417
418 /* be sure the hardware's done with the qh before refreshing
419 * it after fault cleanup, or recovering from silicon wrongly
420 * overlaying the dummy qtd (which reduces DMA chatter).
421 */
422 if (stopped != 0 || qh->hw_qtd_next == EHCI_LIST_END) {
423 switch (state) {
424 case QH_STATE_IDLE:
425 qh_refresh(ehci, qh);
426 break;
427 case QH_STATE_LINKED:
428 /* should be rare for periodic transfers,
429 * except maybe high bandwidth ...
430 */
David Brownell7dedacf2005-08-04 18:06:41 -0700431 if ((__constant_cpu_to_le32 (QH_SMASK)
432 & qh->hw_info2) != 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433 intr_deschedule (ehci, qh);
434 (void) qh_schedule (ehci, qh);
435 } else
436 unlink_async (ehci, qh);
437 break;
438 /* otherwise, unlink already started */
439 }
440 }
441
442 return count;
443}
444
445/*-------------------------------------------------------------------------*/
446
447// high bandwidth multiplier, as encoded in highspeed endpoint descriptors
448#define hb_mult(wMaxPacketSize) (1 + (((wMaxPacketSize) >> 11) & 0x03))
449// ... and packet size, for any kind of endpoint descriptor
450#define max_packet(wMaxPacketSize) ((wMaxPacketSize) & 0x07ff)
451
452/*
453 * reverse of qh_urb_transaction: free a list of TDs.
454 * used for cleanup after errors, before HC sees an URB's TDs.
455 */
456static void qtd_list_free (
457 struct ehci_hcd *ehci,
458 struct urb *urb,
459 struct list_head *qtd_list
460) {
461 struct list_head *entry, *temp;
462
463 list_for_each_safe (entry, temp, qtd_list) {
464 struct ehci_qtd *qtd;
465
466 qtd = list_entry (entry, struct ehci_qtd, qtd_list);
467 list_del (&qtd->qtd_list);
468 ehci_qtd_free (ehci, qtd);
469 }
470}
471
472/*
473 * create a list of filled qtds for this URB; won't link into qh.
474 */
475static struct list_head *
476qh_urb_transaction (
477 struct ehci_hcd *ehci,
478 struct urb *urb,
479 struct list_head *head,
Al Viro55016f12005-10-21 03:21:58 -0400480 gfp_t flags
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481) {
482 struct ehci_qtd *qtd, *qtd_prev;
483 dma_addr_t buf;
484 int len, maxpacket;
485 int is_input;
486 u32 token;
487
488 /*
489 * URBs map to sequences of QTDs: one logical transaction
490 */
491 qtd = ehci_qtd_alloc (ehci, flags);
492 if (unlikely (!qtd))
493 return NULL;
494 list_add_tail (&qtd->qtd_list, head);
495 qtd->urb = urb;
496
497 token = QTD_STS_ACTIVE;
498 token |= (EHCI_TUNE_CERR << 10);
499 /* for split transactions, SplitXState initialized to zero */
500
501 len = urb->transfer_buffer_length;
502 is_input = usb_pipein (urb->pipe);
503 if (usb_pipecontrol (urb->pipe)) {
504 /* SETUP pid */
505 qtd_fill (qtd, urb->setup_dma, sizeof (struct usb_ctrlrequest),
506 token | (2 /* "setup" */ << 8), 8);
507
508 /* ... and always at least one more pid */
509 token ^= QTD_TOGGLE;
510 qtd_prev = qtd;
511 qtd = ehci_qtd_alloc (ehci, flags);
512 if (unlikely (!qtd))
513 goto cleanup;
514 qtd->urb = urb;
515 qtd_prev->hw_next = QTD_NEXT (qtd->qtd_dma);
516 list_add_tail (&qtd->qtd_list, head);
Alan Stern69123542005-11-03 11:44:49 -0500517
518 /* for zero length DATA stages, STATUS is always IN */
519 if (len == 0)
520 token |= (1 /* "in" */ << 8);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700521 }
522
523 /*
524 * data transfer stage: buffer setup
525 */
Alan Stern69123542005-11-03 11:44:49 -0500526 buf = urb->transfer_dma;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527
Alan Stern69123542005-11-03 11:44:49 -0500528 if (is_input)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529 token |= (1 /* "in" */ << 8);
530 /* else it's already initted to "out" pid (0 << 8) */
531
532 maxpacket = max_packet(usb_maxpacket(urb->dev, urb->pipe, !is_input));
533
534 /*
535 * buffer gets wrapped in one or more qtds;
536 * last one may be "short" (including zero len)
537 * and may serve as a control status ack
538 */
539 for (;;) {
540 int this_qtd_len;
541
542 this_qtd_len = qtd_fill (qtd, buf, len, token, maxpacket);
543 len -= this_qtd_len;
544 buf += this_qtd_len;
545 if (is_input)
546 qtd->hw_alt_next = ehci->async->hw_alt_next;
547
548 /* qh makes control packets use qtd toggle; maybe switch it */
549 if ((maxpacket & (this_qtd_len + (maxpacket - 1))) == 0)
550 token ^= QTD_TOGGLE;
551
552 if (likely (len <= 0))
553 break;
554
555 qtd_prev = qtd;
556 qtd = ehci_qtd_alloc (ehci, flags);
557 if (unlikely (!qtd))
558 goto cleanup;
559 qtd->urb = urb;
560 qtd_prev->hw_next = QTD_NEXT (qtd->qtd_dma);
561 list_add_tail (&qtd->qtd_list, head);
562 }
563
564 /* unless the bulk/interrupt caller wants a chance to clean
565 * up after short reads, hc should advance qh past this urb
566 */
567 if (likely ((urb->transfer_flags & URB_SHORT_NOT_OK) == 0
568 || usb_pipecontrol (urb->pipe)))
569 qtd->hw_alt_next = EHCI_LIST_END;
570
571 /*
572 * control requests may need a terminating data "status" ack;
573 * bulk ones may need a terminating short packet (zero length).
574 */
Alan Stern69123542005-11-03 11:44:49 -0500575 if (likely (urb->transfer_buffer_length != 0)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700576 int one_more = 0;
577
578 if (usb_pipecontrol (urb->pipe)) {
579 one_more = 1;
580 token ^= 0x0100; /* "in" <--> "out" */
581 token |= QTD_TOGGLE; /* force DATA1 */
582 } else if (usb_pipebulk (urb->pipe)
583 && (urb->transfer_flags & URB_ZERO_PACKET)
584 && !(urb->transfer_buffer_length % maxpacket)) {
585 one_more = 1;
586 }
587 if (one_more) {
588 qtd_prev = qtd;
589 qtd = ehci_qtd_alloc (ehci, flags);
590 if (unlikely (!qtd))
591 goto cleanup;
592 qtd->urb = urb;
593 qtd_prev->hw_next = QTD_NEXT (qtd->qtd_dma);
594 list_add_tail (&qtd->qtd_list, head);
595
596 /* never any data in such packets */
597 qtd_fill (qtd, 0, 0, token, 0);
598 }
599 }
600
601 /* by default, enable interrupt on urb completion */
602 if (likely (!(urb->transfer_flags & URB_NO_INTERRUPT)))
603 qtd->hw_token |= __constant_cpu_to_le32 (QTD_IOC);
604 return head;
605
606cleanup:
607 qtd_list_free (ehci, urb, head);
608 return NULL;
609}
610
611/*-------------------------------------------------------------------------*/
612
613// Would be best to create all qh's from config descriptors,
614// when each interface/altsetting is established. Unlink
615// any previous qh and cancel its urbs first; endpoints are
616// implicitly reset then (data toggle too).
617// That'd mean updating how usbcore talks to HCDs. (2.7?)
618
619
620/*
621 * Each QH holds a qtd list; a QH is used for everything except iso.
622 *
623 * For interrupt urbs, the scheduler must set the microframe scheduling
624 * mask(s) each time the QH gets scheduled. For highspeed, that's
625 * just one microframe in the s-mask. For split interrupt transactions
626 * there are additional complications: c-mask, maybe FSTNs.
627 */
628static struct ehci_qh *
629qh_make (
630 struct ehci_hcd *ehci,
631 struct urb *urb,
Al Viro55016f12005-10-21 03:21:58 -0400632 gfp_t flags
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633) {
634 struct ehci_qh *qh = ehci_qh_alloc (ehci, flags);
635 u32 info1 = 0, info2 = 0;
636 int is_input, type;
637 int maxp = 0;
638
639 if (!qh)
640 return qh;
641
642 /*
643 * init endpoint/device data for this QH
644 */
645 info1 |= usb_pipeendpoint (urb->pipe) << 8;
646 info1 |= usb_pipedevice (urb->pipe) << 0;
647
648 is_input = usb_pipein (urb->pipe);
649 type = usb_pipetype (urb->pipe);
650 maxp = usb_maxpacket (urb->dev, urb->pipe, !is_input);
651
652 /* Compute interrupt scheduling parameters just once, and save.
653 * - allowing for high bandwidth, how many nsec/uframe are used?
654 * - split transactions need a second CSPLIT uframe; same question
655 * - splits also need a schedule gap (for full/low speed I/O)
656 * - qh has a polling interval
657 *
658 * For control/bulk requests, the HC or TT handles these.
659 */
660 if (type == PIPE_INTERRUPT) {
Dan Streetman498f78e2005-07-29 12:18:28 -0700661 qh->usecs = NS_TO_US (usb_calc_bus_time (USB_SPEED_HIGH, is_input, 0,
662 hb_mult (maxp) * max_packet (maxp)));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 qh->start = NO_FRAME;
664
665 if (urb->dev->speed == USB_SPEED_HIGH) {
666 qh->c_usecs = 0;
667 qh->gap_uf = 0;
668
669 qh->period = urb->interval >> 3;
670 if (qh->period == 0 && urb->interval != 1) {
671 /* NOTE interval 2 or 4 uframes could work.
672 * But interval 1 scheduling is simpler, and
673 * includes high bandwidth.
674 */
675 dbg ("intr period %d uframes, NYET!",
676 urb->interval);
677 goto done;
678 }
679 } else {
david-b@pacbell.netd0384202005-08-13 18:44:58 -0700680 struct usb_tt *tt = urb->dev->tt;
681 int think_time;
682
Linus Torvalds1da177e2005-04-16 15:20:36 -0700683 /* gap is f(FS/LS transfer times) */
684 qh->gap_uf = 1 + usb_calc_bus_time (urb->dev->speed,
685 is_input, 0, maxp) / (125 * 1000);
686
687 /* FIXME this just approximates SPLIT/CSPLIT times */
688 if (is_input) { // SPLIT, gap, CSPLIT+DATA
689 qh->c_usecs = qh->usecs + HS_USECS (0);
690 qh->usecs = HS_USECS (1);
691 } else { // SPLIT+DATA, gap, CSPLIT
692 qh->usecs += HS_USECS (1);
693 qh->c_usecs = HS_USECS (0);
694 }
695
david-b@pacbell.netd0384202005-08-13 18:44:58 -0700696 think_time = tt ? tt->think_time : 0;
697 qh->tt_usecs = NS_TO_US (think_time +
698 usb_calc_bus_time (urb->dev->speed,
699 is_input, 0, max_packet (maxp)));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700700 qh->period = urb->interval;
701 }
702 }
703
704 /* support for tt scheduling, and access to toggles */
705 qh->dev = usb_get_dev (urb->dev);
706
707 /* using TT? */
708 switch (urb->dev->speed) {
709 case USB_SPEED_LOW:
710 info1 |= (1 << 12); /* EPS "low" */
711 /* FALL THROUGH */
712
713 case USB_SPEED_FULL:
714 /* EPS 0 means "full" */
715 if (type != PIPE_INTERRUPT)
716 info1 |= (EHCI_TUNE_RL_TT << 28);
717 if (type == PIPE_CONTROL) {
718 info1 |= (1 << 27); /* for TT */
719 info1 |= 1 << 14; /* toggle from qtd */
720 }
721 info1 |= maxp << 16;
722
723 info2 |= (EHCI_TUNE_MULT_TT << 30);
724 info2 |= urb->dev->ttport << 23;
725
726 /* set the address of the TT; for TDI's integrated
727 * root hub tt, leave it zeroed.
728 */
729 if (!ehci_is_TDI(ehci)
730 || urb->dev->tt->hub !=
731 ehci_to_hcd(ehci)->self.root_hub)
732 info2 |= urb->dev->tt->hub->devnum << 16;
733
734 /* NOTE: if (PIPE_INTERRUPT) { scheduler sets c-mask } */
735
736 break;
737
738 case USB_SPEED_HIGH: /* no TT involved */
739 info1 |= (2 << 12); /* EPS "high" */
740 if (type == PIPE_CONTROL) {
741 info1 |= (EHCI_TUNE_RL_HS << 28);
742 info1 |= 64 << 16; /* usb2 fixed maxpacket */
743 info1 |= 1 << 14; /* toggle from qtd */
744 info2 |= (EHCI_TUNE_MULT_HS << 30);
745 } else if (type == PIPE_BULK) {
746 info1 |= (EHCI_TUNE_RL_HS << 28);
747 info1 |= 512 << 16; /* usb2 fixed maxpacket */
748 info2 |= (EHCI_TUNE_MULT_HS << 30);
749 } else { /* PIPE_INTERRUPT */
750 info1 |= max_packet (maxp) << 16;
751 info2 |= hb_mult (maxp) << 30;
752 }
753 break;
754 default:
755 dbg ("bogus dev %p speed %d", urb->dev, urb->dev->speed);
756done:
757 qh_put (qh);
758 return NULL;
759 }
760
761 /* NOTE: if (PIPE_INTERRUPT) { scheduler sets s-mask } */
762
763 /* init as live, toggle clear, advance to dummy */
764 qh->qh_state = QH_STATE_IDLE;
765 qh->hw_info1 = cpu_to_le32 (info1);
766 qh->hw_info2 = cpu_to_le32 (info2);
767 usb_settoggle (urb->dev, usb_pipeendpoint (urb->pipe), !is_input, 1);
768 qh_refresh (ehci, qh);
769 return qh;
770}
771
772/*-------------------------------------------------------------------------*/
773
774/* move qh (and its qtds) onto async queue; maybe enable queue. */
775
776static void qh_link_async (struct ehci_hcd *ehci, struct ehci_qh *qh)
777{
778 __le32 dma = QH_NEXT (qh->qh_dma);
779 struct ehci_qh *head;
780
781 /* (re)start the async schedule? */
782 head = ehci->async;
783 timer_action_done (ehci, TIMER_ASYNC_OFF);
784 if (!head->qh_next.qh) {
785 u32 cmd = readl (&ehci->regs->command);
786
787 if (!(cmd & CMD_ASE)) {
788 /* in case a clear of CMD_ASE didn't take yet */
789 (void) handshake (&ehci->regs->status, STS_ASS, 0, 150);
790 cmd |= CMD_ASE | CMD_RUN;
791 writel (cmd, &ehci->regs->command);
792 ehci_to_hcd(ehci)->state = HC_STATE_RUNNING;
793 /* posted write need not be known to HC yet ... */
794 }
795 }
796
797 /* clear halt and/or toggle; and maybe recover from silicon quirk */
798 if (qh->qh_state == QH_STATE_IDLE)
799 qh_refresh (ehci, qh);
800
801 /* splice right after start */
802 qh->qh_next = head->qh_next;
803 qh->hw_next = head->hw_next;
804 wmb ();
805
806 head->qh_next.qh = qh;
807 head->hw_next = dma;
808
809 qh->qh_state = QH_STATE_LINKED;
810 /* qtd completions reported later by interrupt */
811}
812
813/*-------------------------------------------------------------------------*/
814
815#define QH_ADDR_MASK __constant_cpu_to_le32(0x7f)
816
817/*
818 * For control/bulk/interrupt, return QH with these TDs appended.
819 * Allocates and initializes the QH if necessary.
820 * Returns null if it can't allocate a QH it needs to.
821 * If the QH has TDs (urbs) already, that's great.
822 */
823static struct ehci_qh *qh_append_tds (
824 struct ehci_hcd *ehci,
825 struct urb *urb,
826 struct list_head *qtd_list,
827 int epnum,
828 void **ptr
829)
830{
831 struct ehci_qh *qh = NULL;
832
833 qh = (struct ehci_qh *) *ptr;
834 if (unlikely (qh == NULL)) {
835 /* can't sleep here, we have ehci->lock... */
836 qh = qh_make (ehci, urb, GFP_ATOMIC);
837 *ptr = qh;
838 }
839 if (likely (qh != NULL)) {
840 struct ehci_qtd *qtd;
841
842 if (unlikely (list_empty (qtd_list)))
843 qtd = NULL;
844 else
845 qtd = list_entry (qtd_list->next, struct ehci_qtd,
846 qtd_list);
847
848 /* control qh may need patching ... */
849 if (unlikely (epnum == 0)) {
850
851 /* usb_reset_device() briefly reverts to address 0 */
852 if (usb_pipedevice (urb->pipe) == 0)
853 qh->hw_info1 &= ~QH_ADDR_MASK;
854 }
855
856 /* just one way to queue requests: swap with the dummy qtd.
857 * only hc or qh_refresh() ever modify the overlay.
858 */
859 if (likely (qtd != NULL)) {
860 struct ehci_qtd *dummy;
861 dma_addr_t dma;
862 __le32 token;
863
864 /* to avoid racing the HC, use the dummy td instead of
865 * the first td of our list (becomes new dummy). both
866 * tds stay deactivated until we're done, when the
867 * HC is allowed to fetch the old dummy (4.10.2).
868 */
869 token = qtd->hw_token;
870 qtd->hw_token = HALT_BIT;
871 wmb ();
872 dummy = qh->dummy;
873
874 dma = dummy->qtd_dma;
875 *dummy = *qtd;
876 dummy->qtd_dma = dma;
877
878 list_del (&qtd->qtd_list);
879 list_add (&dummy->qtd_list, qtd_list);
880 __list_splice (qtd_list, qh->qtd_list.prev);
881
882 ehci_qtd_init (qtd, qtd->qtd_dma);
883 qh->dummy = qtd;
884
885 /* hc must see the new dummy at list end */
886 dma = qtd->qtd_dma;
887 qtd = list_entry (qh->qtd_list.prev,
888 struct ehci_qtd, qtd_list);
889 qtd->hw_next = QTD_NEXT (dma);
890
891 /* let the hc process these next qtds */
892 wmb ();
893 dummy->hw_token = token;
894
895 urb->hcpriv = qh_get (qh);
896 }
897 }
898 return qh;
899}
900
901/*-------------------------------------------------------------------------*/
902
903static int
904submit_async (
905 struct ehci_hcd *ehci,
906 struct usb_host_endpoint *ep,
907 struct urb *urb,
908 struct list_head *qtd_list,
Al Viro55016f12005-10-21 03:21:58 -0400909 gfp_t mem_flags
Linus Torvalds1da177e2005-04-16 15:20:36 -0700910) {
911 struct ehci_qtd *qtd;
912 int epnum;
913 unsigned long flags;
914 struct ehci_qh *qh = NULL;
Benjamin Herrenschmidt8de98402005-11-25 09:59:46 +1100915 int rc = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916
917 qtd = list_entry (qtd_list->next, struct ehci_qtd, qtd_list);
918 epnum = ep->desc.bEndpointAddress;
919
920#ifdef EHCI_URB_TRACE
921 ehci_dbg (ehci,
922 "%s %s urb %p ep%d%s len %d, qtd %p [qh %p]\n",
923 __FUNCTION__, urb->dev->devpath, urb,
924 epnum & 0x0f, (epnum & USB_DIR_IN) ? "in" : "out",
925 urb->transfer_buffer_length,
926 qtd, ep->hcpriv);
927#endif
928
929 spin_lock_irqsave (&ehci->lock, flags);
Benjamin Herrenschmidt8de98402005-11-25 09:59:46 +1100930 if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE,
931 &ehci_to_hcd(ehci)->flags))) {
932 rc = -ESHUTDOWN;
933 goto done;
934 }
935
Linus Torvalds1da177e2005-04-16 15:20:36 -0700936 qh = qh_append_tds (ehci, urb, qtd_list, epnum, &ep->hcpriv);
Benjamin Herrenschmidt8de98402005-11-25 09:59:46 +1100937 if (unlikely(qh == NULL)) {
938 rc = -ENOMEM;
939 goto done;
940 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700941
942 /* Control/bulk operations through TTs don't need scheduling,
943 * the HC and TT handle it when the TT has a buffer ready.
944 */
Benjamin Herrenschmidt8de98402005-11-25 09:59:46 +1100945 if (likely (qh->qh_state == QH_STATE_IDLE))
946 qh_link_async (ehci, qh_get (qh));
947 done:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700948 spin_unlock_irqrestore (&ehci->lock, flags);
Benjamin Herrenschmidt8de98402005-11-25 09:59:46 +1100949 if (unlikely (qh == NULL))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700950 qtd_list_free (ehci, urb, qtd_list);
Benjamin Herrenschmidt8de98402005-11-25 09:59:46 +1100951 return rc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700952}
953
954/*-------------------------------------------------------------------------*/
955
956/* the async qh for the qtds being reclaimed are now unlinked from the HC */
957
958static void end_unlink_async (struct ehci_hcd *ehci, struct pt_regs *regs)
959{
960 struct ehci_qh *qh = ehci->reclaim;
961 struct ehci_qh *next;
962
963 timer_action_done (ehci, TIMER_IAA_WATCHDOG);
964
965 // qh->hw_next = cpu_to_le32 (qh->qh_dma);
966 qh->qh_state = QH_STATE_IDLE;
967 qh->qh_next.qh = NULL;
968 qh_put (qh); // refcount from reclaim
969
970 /* other unlink(s) may be pending (in QH_STATE_UNLINK_WAIT) */
971 next = qh->reclaim;
972 ehci->reclaim = next;
973 ehci->reclaim_ready = 0;
974 qh->reclaim = NULL;
975
976 qh_completions (ehci, qh, regs);
977
978 if (!list_empty (&qh->qtd_list)
979 && HC_IS_RUNNING (ehci_to_hcd(ehci)->state))
980 qh_link_async (ehci, qh);
981 else {
982 qh_put (qh); // refcount from async list
983
984 /* it's not free to turn the async schedule on/off; leave it
985 * active but idle for a while once it empties.
986 */
987 if (HC_IS_RUNNING (ehci_to_hcd(ehci)->state)
988 && ehci->async->qh_next.qh == NULL)
989 timer_action (ehci, TIMER_ASYNC_OFF);
990 }
991
992 if (next) {
993 ehci->reclaim = NULL;
994 start_unlink_async (ehci, next);
995 }
996}
997
998/* makes sure the async qh will become idle */
999/* caller must own ehci->lock */
1000
1001static void start_unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh)
1002{
1003 int cmd = readl (&ehci->regs->command);
1004 struct ehci_qh *prev;
1005
1006#ifdef DEBUG
1007 assert_spin_locked(&ehci->lock);
1008 if (ehci->reclaim
1009 || (qh->qh_state != QH_STATE_LINKED
1010 && qh->qh_state != QH_STATE_UNLINK_WAIT)
1011 )
1012 BUG ();
1013#endif
1014
1015 /* stop async schedule right now? */
1016 if (unlikely (qh == ehci->async)) {
1017 /* can't get here without STS_ASS set */
1018 if (ehci_to_hcd(ehci)->state != HC_STATE_HALT) {
1019 writel (cmd & ~CMD_ASE, &ehci->regs->command);
1020 wmb ();
1021 // handshake later, if we need to
1022 }
1023 timer_action_done (ehci, TIMER_ASYNC_OFF);
1024 return;
1025 }
1026
1027 qh->qh_state = QH_STATE_UNLINK;
1028 ehci->reclaim = qh = qh_get (qh);
1029
1030 prev = ehci->async;
1031 while (prev->qh_next.qh != qh)
1032 prev = prev->qh_next.qh;
1033
1034 prev->hw_next = qh->hw_next;
1035 prev->qh_next = qh->qh_next;
1036 wmb ();
1037
1038 if (unlikely (ehci_to_hcd(ehci)->state == HC_STATE_HALT)) {
1039 /* if (unlikely (qh->reclaim != 0))
1040 * this will recurse, probably not much
1041 */
1042 end_unlink_async (ehci, NULL);
1043 return;
1044 }
1045
1046 ehci->reclaim_ready = 0;
1047 cmd |= CMD_IAAD;
1048 writel (cmd, &ehci->regs->command);
1049 (void) readl (&ehci->regs->command);
1050 timer_action (ehci, TIMER_IAA_WATCHDOG);
1051}
1052
1053/*-------------------------------------------------------------------------*/
1054
1055static void
1056scan_async (struct ehci_hcd *ehci, struct pt_regs *regs)
1057{
1058 struct ehci_qh *qh;
1059 enum ehci_timer_action action = TIMER_IO_WATCHDOG;
1060
1061 if (!++(ehci->stamp))
1062 ehci->stamp++;
1063 timer_action_done (ehci, TIMER_ASYNC_SHRINK);
1064rescan:
1065 qh = ehci->async->qh_next.qh;
1066 if (likely (qh != NULL)) {
1067 do {
1068 /* clean any finished work for this qh */
1069 if (!list_empty (&qh->qtd_list)
1070 && qh->stamp != ehci->stamp) {
1071 int temp;
1072
1073 /* unlinks could happen here; completion
1074 * reporting drops the lock. rescan using
1075 * the latest schedule, but don't rescan
1076 * qhs we already finished (no looping).
1077 */
1078 qh = qh_get (qh);
1079 qh->stamp = ehci->stamp;
1080 temp = qh_completions (ehci, qh, regs);
1081 qh_put (qh);
1082 if (temp != 0) {
1083 goto rescan;
1084 }
1085 }
1086
1087 /* unlink idle entries, reducing HC PCI usage as well
1088 * as HCD schedule-scanning costs. delay for any qh
1089 * we just scanned, there's a not-unusual case that it
1090 * doesn't stay idle for long.
1091 * (plus, avoids some kind of re-activation race.)
1092 */
1093 if (list_empty (&qh->qtd_list)) {
1094 if (qh->stamp == ehci->stamp)
1095 action = TIMER_ASYNC_SHRINK;
1096 else if (!ehci->reclaim
1097 && qh->qh_state == QH_STATE_LINKED)
1098 start_unlink_async (ehci, qh);
1099 }
1100
1101 qh = qh->qh_next.qh;
1102 } while (qh);
1103 }
1104 if (action == TIMER_ASYNC_SHRINK)
1105 timer_action (ehci, TIMER_ASYNC_SHRINK);
1106}