2 * Copyright (C) 2001-2004 by David Brownell
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.
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
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.
19 /* this file is part of ehci-hcd.c */
21 /*-------------------------------------------------------------------------*/
24 * EHCI hardware queue manipulation ... the core. QH/QTD manipulation.
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.
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".
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.
41 /*-------------------------------------------------------------------------*/
43 /* fill a qtd, returning how much of the buffer we were able to queue up */
46 qtd_fill(struct ehci_hcd
*ehci
, struct ehci_qtd
*qtd
, dma_addr_t buf
,
47 size_t len
, int token
, int maxpacket
)
52 /* one buffer entry per 4K ... first might be short or unaligned */
53 qtd
->hw_buf
[0] = cpu_to_hc32(ehci
, (u32
)addr
);
54 qtd
->hw_buf_hi
[0] = cpu_to_hc32(ehci
, (u32
)(addr
>> 32));
55 count
= 0x1000 - (buf
& 0x0fff); /* rest of that page */
56 if (likely (len
< count
)) /* ... iff needed */
62 /* per-qtd limit: from 16K to 20K (best alignment) */
63 for (i
= 1; count
< len
&& i
< 5; i
++) {
65 qtd
->hw_buf
[i
] = cpu_to_hc32(ehci
, (u32
)addr
);
66 qtd
->hw_buf_hi
[i
] = cpu_to_hc32(ehci
,
69 if ((count
+ 0x1000) < len
)
75 /* short packets may only terminate transfers */
77 count
-= (count
% maxpacket
);
79 qtd
->hw_token
= cpu_to_hc32(ehci
, (count
<< 16) | token
);
85 /*-------------------------------------------------------------------------*/
88 qh_update (struct ehci_hcd
*ehci
, struct ehci_qh
*qh
, struct ehci_qtd
*qtd
)
90 struct ehci_qh_hw
*hw
= qh
->hw
;
92 /* writes to an active overlay are unsafe */
93 BUG_ON(qh
->qh_state
!= QH_STATE_IDLE
);
95 hw
->hw_qtd_next
= QTD_NEXT(ehci
, qtd
->qtd_dma
);
96 hw
->hw_alt_next
= EHCI_LIST_END(ehci
);
98 /* Except for control endpoints, we make hardware maintain data
99 * toggle (like OHCI) ... here (re)initialize the toggle in the QH,
100 * and set the pseudo-toggle in udev. Only usb_clear_halt() will
103 if (!(hw
->hw_info1
& cpu_to_hc32(ehci
, QH_TOGGLE_CTL
))) {
104 unsigned is_out
, epnum
;
107 epnum
= (hc32_to_cpup(ehci
, &hw
->hw_info1
) >> 8) & 0x0f;
108 if (unlikely (!usb_gettoggle (qh
->dev
, epnum
, is_out
))) {
109 hw
->hw_token
&= ~cpu_to_hc32(ehci
, QTD_TOGGLE
);
110 usb_settoggle (qh
->dev
, epnum
, is_out
, 1);
114 hw
->hw_token
&= cpu_to_hc32(ehci
, QTD_TOGGLE
| QTD_STS_PING
);
117 /* if it weren't for a common silicon quirk (writing the dummy into the qh
118 * overlay, so qh->hw_token wrongly becomes inactive/halted), only fault
119 * recovery (including urb dequeue) would need software changes to a QH...
122 qh_refresh (struct ehci_hcd
*ehci
, struct ehci_qh
*qh
)
124 struct ehci_qtd
*qtd
;
126 if (list_empty (&qh
->qtd_list
))
129 qtd
= list_entry (qh
->qtd_list
.next
,
130 struct ehci_qtd
, qtd_list
);
132 * first qtd may already be partially processed.
133 * If we come here during unlink, the QH overlay region
134 * might have reference to the just unlinked qtd. The
135 * qtd is updated in qh_completions(). Update the QH
138 if (cpu_to_hc32(ehci
, qtd
->qtd_dma
) == qh
->hw
->hw_current
) {
139 qh
->hw
->hw_qtd_next
= qtd
->hw_next
;
145 qh_update (ehci
, qh
, qtd
);
148 /*-------------------------------------------------------------------------*/
150 static void qh_link_async(struct ehci_hcd
*ehci
, struct ehci_qh
*qh
);
152 static void ehci_clear_tt_buffer_complete(struct usb_hcd
*hcd
,
153 struct usb_host_endpoint
*ep
)
155 struct ehci_hcd
*ehci
= hcd_to_ehci(hcd
);
156 struct ehci_qh
*qh
= ep
->hcpriv
;
159 spin_lock_irqsave(&ehci
->lock
, flags
);
161 if (qh
->qh_state
== QH_STATE_IDLE
&& !list_empty(&qh
->qtd_list
)
162 && ehci
->rh_state
== EHCI_RH_RUNNING
)
163 qh_link_async(ehci
, qh
);
164 spin_unlock_irqrestore(&ehci
->lock
, flags
);
167 static void ehci_clear_tt_buffer(struct ehci_hcd
*ehci
, struct ehci_qh
*qh
,
168 struct urb
*urb
, u32 token
)
171 /* If an async split transaction gets an error or is unlinked,
172 * the TT buffer may be left in an indeterminate state. We
173 * have to clear the TT buffer.
175 * Note: this routine is never called for Isochronous transfers.
177 if (urb
->dev
->tt
&& !usb_pipeint(urb
->pipe
) && !qh
->clearing_tt
) {
179 struct usb_device
*tt
= urb
->dev
->tt
->hub
;
181 "clear tt buffer port %d, a%d ep%d t%08x\n",
182 urb
->dev
->ttport
, urb
->dev
->devnum
,
183 usb_pipeendpoint(urb
->pipe
), token
);
185 if (!ehci_is_TDI(ehci
)
186 || urb
->dev
->tt
->hub
!=
187 ehci_to_hcd(ehci
)->self
.root_hub
) {
188 if (usb_hub_clear_tt_buffer(urb
) == 0)
192 /* REVISIT ARC-derived cores don't clear the root
193 * hub TT buffer in this way...
199 static int qtd_copy_status (
200 struct ehci_hcd
*ehci
,
206 int status
= -EINPROGRESS
;
208 /* count IN/OUT bytes, not SETUP (even short packets) */
209 if (likely (QTD_PID (token
) != 2))
210 urb
->actual_length
+= length
- QTD_LENGTH (token
);
212 /* don't modify error codes */
213 if (unlikely(urb
->unlinked
))
216 /* force cleanup after short read; not always an error */
217 if (unlikely (IS_SHORT_READ (token
)))
220 /* serious "can't proceed" faults reported by the hardware */
221 if (token
& QTD_STS_HALT
) {
222 if (token
& QTD_STS_BABBLE
) {
223 /* FIXME "must" disable babbling device's port too */
225 /* CERR nonzero + halt --> stall */
226 } else if (QTD_CERR(token
)) {
229 /* In theory, more than one of the following bits can be set
230 * since they are sticky and the transaction is retried.
231 * Which to test first is rather arbitrary.
233 } else if (token
& QTD_STS_MMF
) {
234 /* fs/ls interrupt xfer missed the complete-split */
236 } else if (token
& QTD_STS_DBE
) {
237 status
= (QTD_PID (token
) == 1) /* IN ? */
238 ? -ENOSR
/* hc couldn't read data */
239 : -ECOMM
; /* hc couldn't write data */
240 } else if (token
& QTD_STS_XACT
) {
241 /* timeout, bad CRC, wrong PID, etc */
242 ehci_dbg(ehci
, "devpath %s ep%d%s 3strikes\n",
244 usb_pipeendpoint(urb
->pipe
),
245 usb_pipein(urb
->pipe
) ? "in" : "out");
247 } else { /* unknown */
252 "dev%d ep%d%s qtd token %08x --> status %d\n",
253 usb_pipedevice (urb
->pipe
),
254 usb_pipeendpoint (urb
->pipe
),
255 usb_pipein (urb
->pipe
) ? "in" : "out",
263 ehci_urb_done(struct ehci_hcd
*ehci
, struct urb
*urb
, int status
)
264 __releases(ehci
->lock
)
265 __acquires(ehci
->lock
)
267 if (usb_pipetype(urb
->pipe
) == PIPE_INTERRUPT
) {
268 /* ... update hc-wide periodic stats */
269 ehci_to_hcd(ehci
)->self
.bandwidth_int_reqs
--;
272 if (unlikely(urb
->unlinked
)) {
273 COUNT(ehci
->stats
.unlink
);
275 /* report non-error and short read status as zero */
276 if (status
== -EINPROGRESS
|| status
== -EREMOTEIO
)
278 COUNT(ehci
->stats
.complete
);
281 #ifdef EHCI_URB_TRACE
283 "%s %s urb %p ep%d%s status %d len %d/%d\n",
284 __func__
, urb
->dev
->devpath
, urb
,
285 usb_pipeendpoint (urb
->pipe
),
286 usb_pipein (urb
->pipe
) ? "in" : "out",
288 urb
->actual_length
, urb
->transfer_buffer_length
);
291 /* complete() can reenter this HCD */
292 usb_hcd_unlink_urb_from_ep(ehci_to_hcd(ehci
), urb
);
293 spin_unlock (&ehci
->lock
);
294 usb_hcd_giveback_urb(ehci_to_hcd(ehci
), urb
, status
);
295 spin_lock (&ehci
->lock
);
298 static int qh_schedule (struct ehci_hcd
*ehci
, struct ehci_qh
*qh
);
301 * Process and free completed qtds for a qh, returning URBs to drivers.
302 * Chases up to qh->hw_current. Returns number of completions called,
303 * indicating how much "real" work we did.
306 qh_completions (struct ehci_hcd
*ehci
, struct ehci_qh
*qh
)
308 struct ehci_qtd
*last
, *end
= qh
->dummy
;
309 struct list_head
*entry
, *tmp
;
314 struct ehci_qh_hw
*hw
= qh
->hw
;
316 if (unlikely (list_empty (&qh
->qtd_list
)))
319 /* completions (or tasks on other cpus) must never clobber HALT
320 * till we've gone through and cleaned everything up, even when
321 * they add urbs to this qh's queue or mark them for unlinking.
323 * NOTE: unlinking expects to be done in queue order.
325 * It's a bug for qh->qh_state to be anything other than
326 * QH_STATE_IDLE, unless our caller is scan_async() or
329 state
= qh
->qh_state
;
330 qh
->qh_state
= QH_STATE_COMPLETING
;
331 stopped
= (state
== QH_STATE_IDLE
);
335 last_status
= -EINPROGRESS
;
336 qh
->needs_rescan
= 0;
338 /* remove de-activated QTDs from front of queue.
339 * after faults (including short reads), cleanup this urb
340 * then let the queue advance.
341 * if queue is stopped, handles unlinks.
343 list_for_each_safe (entry
, tmp
, &qh
->qtd_list
) {
344 struct ehci_qtd
*qtd
;
348 qtd
= list_entry (entry
, struct ehci_qtd
, qtd_list
);
351 /* clean up any state from previous QTD ...*/
353 if (likely (last
->urb
!= urb
)) {
354 ehci_urb_done(ehci
, last
->urb
, last_status
);
356 last_status
= -EINPROGRESS
;
358 ehci_qtd_free (ehci
, last
);
362 /* ignore urbs submitted during completions we reported */
366 /* hardware copies qtd out of qh overlay */
368 token
= hc32_to_cpu(ehci
, qtd
->hw_token
);
370 /* always clean up qtds the hc de-activated */
372 if ((token
& QTD_STS_ACTIVE
) == 0) {
374 /* Report Data Buffer Error: non-fatal but useful */
375 if (token
& QTD_STS_DBE
)
377 "detected DataBufferErr for urb %p ep%d%s len %d, qtd %p [qh %p]\n",
379 usb_endpoint_num(&urb
->ep
->desc
),
380 usb_endpoint_dir_in(&urb
->ep
->desc
) ? "in" : "out",
381 urb
->transfer_buffer_length
,
385 /* on STALL, error, and short reads this urb must
386 * complete and all its qtds must be recycled.
388 if ((token
& QTD_STS_HALT
) != 0) {
390 /* retry transaction errors until we
391 * reach the software xacterr limit
393 if ((token
& QTD_STS_XACT
) &&
394 QTD_CERR(token
) == 0 &&
395 ++qh
->xacterrs
< QH_XACTERR_MAX
&&
398 "detected XactErr len %zu/%zu retry %d\n",
399 qtd
->length
- QTD_LENGTH(token
), qtd
->length
, qh
->xacterrs
);
401 /* reset the token in the qtd and the
402 * qh overlay (which still contains
403 * the qtd) so that we pick up from
406 token
&= ~QTD_STS_HALT
;
407 token
|= QTD_STS_ACTIVE
|
408 (EHCI_TUNE_CERR
<< 10);
409 qtd
->hw_token
= cpu_to_hc32(ehci
,
412 hw
->hw_token
= cpu_to_hc32(ehci
,
418 /* magic dummy for some short reads; qh won't advance.
419 * that silicon quirk can kick in with this dummy too.
421 * other short reads won't stop the queue, including
422 * control transfers (status stage handles that) or
423 * most other single-qtd reads ... the queue stops if
424 * URB_SHORT_NOT_OK was set so the driver submitting
425 * the urbs could clean it up.
427 } else if (IS_SHORT_READ (token
)
428 && !(qtd
->hw_alt_next
429 & EHCI_LIST_END(ehci
))) {
433 /* stop scanning when we reach qtds the hc is using */
434 } else if (likely (!stopped
435 && ehci
->rh_state
>= EHCI_RH_RUNNING
)) {
438 /* scan the whole queue for unlinks whenever it stops */
442 /* cancel everything if we halt, suspend, etc */
443 if (ehci
->rh_state
< EHCI_RH_RUNNING
)
444 last_status
= -ESHUTDOWN
;
446 /* this qtd is active; skip it unless a previous qtd
447 * for its urb faulted, or its urb was canceled.
449 else if (last_status
== -EINPROGRESS
&& !urb
->unlinked
)
452 /* qh unlinked; token in overlay may be most current */
453 if (state
== QH_STATE_IDLE
454 && cpu_to_hc32(ehci
, qtd
->qtd_dma
)
456 token
= hc32_to_cpu(ehci
, hw
->hw_token
);
458 /* An unlink may leave an incomplete
459 * async transaction in the TT buffer.
460 * We have to clear it.
462 ehci_clear_tt_buffer(ehci
, qh
, urb
, token
);
466 /* unless we already know the urb's status, collect qtd status
467 * and update count of bytes transferred. in common short read
468 * cases with only one data qtd (including control transfers),
469 * queue processing won't halt. but with two or more qtds (for
470 * example, with a 32 KB transfer), when the first qtd gets a
471 * short read the second must be removed by hand.
473 if (last_status
== -EINPROGRESS
) {
474 last_status
= qtd_copy_status(ehci
, urb
,
476 if (last_status
== -EREMOTEIO
478 & EHCI_LIST_END(ehci
)))
479 last_status
= -EINPROGRESS
;
481 /* As part of low/full-speed endpoint-halt processing
482 * we must clear the TT buffer (11.17.5).
484 if (unlikely(last_status
!= -EINPROGRESS
&&
485 last_status
!= -EREMOTEIO
)) {
486 /* The TT's in some hubs malfunction when they
487 * receive this request following a STALL (they
488 * stop sending isochronous packets). Since a
489 * STALL can't leave the TT buffer in a busy
490 * state (if you believe Figures 11-48 - 11-51
491 * in the USB 2.0 spec), we won't clear the TT
492 * buffer in this case. Strictly speaking this
493 * is a violation of the spec.
495 if (last_status
!= -EPIPE
)
496 ehci_clear_tt_buffer(ehci
, qh
, urb
,
501 /* if we're removing something not at the queue head,
502 * patch the hardware queue pointer.
504 if (stopped
&& qtd
->qtd_list
.prev
!= &qh
->qtd_list
) {
505 last
= list_entry (qtd
->qtd_list
.prev
,
506 struct ehci_qtd
, qtd_list
);
507 last
->hw_next
= qtd
->hw_next
;
510 /* remove qtd; it's recycled after possible urb completion */
511 list_del (&qtd
->qtd_list
);
514 /* reinit the xacterr counter for the next qtd */
518 /* last urb's completion might still need calling */
519 if (likely (last
!= NULL
)) {
520 ehci_urb_done(ehci
, last
->urb
, last_status
);
522 ehci_qtd_free (ehci
, last
);
525 /* Do we need to rescan for URBs dequeued during a giveback? */
526 if (unlikely(qh
->needs_rescan
)) {
527 /* If the QH is already unlinked, do the rescan now. */
528 if (state
== QH_STATE_IDLE
)
531 /* Otherwise we have to wait until the QH is fully unlinked.
532 * Our caller will start an unlink if qh->needs_rescan is
533 * set. But if an unlink has already started, nothing needs
536 if (state
!= QH_STATE_LINKED
)
537 qh
->needs_rescan
= 0;
540 /* restore original state; caller must unlink or relink */
541 qh
->qh_state
= state
;
543 /* be sure the hardware's done with the qh before refreshing
544 * it after fault cleanup, or recovering from silicon wrongly
545 * overlaying the dummy qtd (which reduces DMA chatter).
547 if (stopped
!= 0 || hw
->hw_qtd_next
== EHCI_LIST_END(ehci
)) {
550 qh_refresh(ehci
, qh
);
552 case QH_STATE_LINKED
:
553 /* We won't refresh a QH that's linked (after the HC
554 * stopped the queue). That avoids a race:
555 * - HC reads first part of QH;
556 * - CPU updates that first part and the token;
557 * - HC reads rest of that QH, including token
558 * Result: HC gets an inconsistent image, and then
559 * DMAs to/from the wrong memory (corrupting it).
561 * That should be rare for interrupt transfers,
562 * except maybe high bandwidth ...
565 /* Tell the caller to start an unlink */
566 qh
->needs_rescan
= 1;
568 /* otherwise, unlink already started */
575 /*-------------------------------------------------------------------------*/
577 // high bandwidth multiplier, as encoded in highspeed endpoint descriptors
578 #define hb_mult(wMaxPacketSize) (1 + (((wMaxPacketSize) >> 11) & 0x03))
579 // ... and packet size, for any kind of endpoint descriptor
580 #define max_packet(wMaxPacketSize) ((wMaxPacketSize) & 0x07ff)
583 * reverse of qh_urb_transaction: free a list of TDs.
584 * used for cleanup after errors, before HC sees an URB's TDs.
586 static void qtd_list_free (
587 struct ehci_hcd
*ehci
,
589 struct list_head
*qtd_list
591 struct list_head
*entry
, *temp
;
593 list_for_each_safe (entry
, temp
, qtd_list
) {
594 struct ehci_qtd
*qtd
;
596 qtd
= list_entry (entry
, struct ehci_qtd
, qtd_list
);
597 list_del (&qtd
->qtd_list
);
598 ehci_qtd_free (ehci
, qtd
);
603 * create a list of filled qtds for this URB; won't link into qh.
605 static struct list_head
*
607 struct ehci_hcd
*ehci
,
609 struct list_head
*head
,
612 struct ehci_qtd
*qtd
, *qtd_prev
;
614 int len
, this_sg_len
, maxpacket
;
618 struct scatterlist
*sg
;
621 * URBs map to sequences of QTDs: one logical transaction
623 qtd
= ehci_qtd_alloc (ehci
, flags
);
626 list_add_tail (&qtd
->qtd_list
, head
);
629 token
= QTD_STS_ACTIVE
;
630 token
|= (EHCI_TUNE_CERR
<< 10);
631 /* for split transactions, SplitXState initialized to zero */
633 len
= urb
->transfer_buffer_length
;
634 is_input
= usb_pipein (urb
->pipe
);
635 if (usb_pipecontrol (urb
->pipe
)) {
637 qtd_fill(ehci
, qtd
, urb
->setup_dma
,
638 sizeof (struct usb_ctrlrequest
),
639 token
| (2 /* "setup" */ << 8), 8);
641 /* ... and always at least one more pid */
644 qtd
= ehci_qtd_alloc (ehci
, flags
);
648 qtd_prev
->hw_next
= QTD_NEXT(ehci
, qtd
->qtd_dma
);
649 list_add_tail (&qtd
->qtd_list
, head
);
651 /* for zero length DATA stages, STATUS is always IN */
653 token
|= (1 /* "in" */ << 8);
657 * data transfer stage: buffer setup
659 i
= urb
->num_mapped_sgs
;
660 if (len
> 0 && i
> 0) {
662 buf
= sg_dma_address(sg
);
664 /* urb->transfer_buffer_length may be smaller than the
665 * size of the scatterlist (or vice versa)
667 this_sg_len
= min_t(int, sg_dma_len(sg
), len
);
670 buf
= urb
->transfer_dma
;
675 token
|= (1 /* "in" */ << 8);
676 /* else it's already initted to "out" pid (0 << 8) */
678 maxpacket
= max_packet(usb_maxpacket(urb
->dev
, urb
->pipe
, !is_input
));
681 * buffer gets wrapped in one or more qtds;
682 * last one may be "short" (including zero len)
683 * and may serve as a control status ack
688 this_qtd_len
= qtd_fill(ehci
, qtd
, buf
, this_sg_len
, token
,
690 this_sg_len
-= this_qtd_len
;
695 * short reads advance to a "magic" dummy instead of the next
696 * qtd ... that forces the queue to stop, for manual cleanup.
697 * (this will usually be overridden later.)
700 qtd
->hw_alt_next
= ehci
->async
->hw
->hw_alt_next
;
702 /* qh makes control packets use qtd toggle; maybe switch it */
703 if ((maxpacket
& (this_qtd_len
+ (maxpacket
- 1))) == 0)
706 if (likely(this_sg_len
<= 0)) {
707 if (--i
<= 0 || len
<= 0)
710 buf
= sg_dma_address(sg
);
711 this_sg_len
= min_t(int, sg_dma_len(sg
), len
);
715 qtd
= ehci_qtd_alloc (ehci
, flags
);
719 qtd_prev
->hw_next
= QTD_NEXT(ehci
, qtd
->qtd_dma
);
720 list_add_tail (&qtd
->qtd_list
, head
);
724 * unless the caller requires manual cleanup after short reads,
725 * have the alt_next mechanism keep the queue running after the
726 * last data qtd (the only one, for control and most other cases).
728 if (likely ((urb
->transfer_flags
& URB_SHORT_NOT_OK
) == 0
729 || usb_pipecontrol (urb
->pipe
)))
730 qtd
->hw_alt_next
= EHCI_LIST_END(ehci
);
733 * control requests may need a terminating data "status" ack;
734 * other OUT ones may need a terminating short packet
737 if (likely (urb
->transfer_buffer_length
!= 0)) {
740 if (usb_pipecontrol (urb
->pipe
)) {
742 token
^= 0x0100; /* "in" <--> "out" */
743 token
|= QTD_TOGGLE
; /* force DATA1 */
744 } else if (usb_pipeout(urb
->pipe
)
745 && (urb
->transfer_flags
& URB_ZERO_PACKET
)
746 && !(urb
->transfer_buffer_length
% maxpacket
)) {
751 qtd
= ehci_qtd_alloc (ehci
, flags
);
755 qtd_prev
->hw_next
= QTD_NEXT(ehci
, qtd
->qtd_dma
);
756 list_add_tail (&qtd
->qtd_list
, head
);
758 /* never any data in such packets */
759 qtd_fill(ehci
, qtd
, 0, 0, token
, 0);
763 /* by default, enable interrupt on urb completion */
764 if (likely (!(urb
->transfer_flags
& URB_NO_INTERRUPT
)))
765 qtd
->hw_token
|= cpu_to_hc32(ehci
, QTD_IOC
);
769 qtd_list_free (ehci
, urb
, head
);
773 /*-------------------------------------------------------------------------*/
775 // Would be best to create all qh's from config descriptors,
776 // when each interface/altsetting is established. Unlink
777 // any previous qh and cancel its urbs first; endpoints are
778 // implicitly reset then (data toggle too).
779 // That'd mean updating how usbcore talks to HCDs. (2.7?)
783 * Each QH holds a qtd list; a QH is used for everything except iso.
785 * For interrupt urbs, the scheduler must set the microframe scheduling
786 * mask(s) each time the QH gets scheduled. For highspeed, that's
787 * just one microframe in the s-mask. For split interrupt transactions
788 * there are additional complications: c-mask, maybe FSTNs.
790 static struct ehci_qh
*
792 struct ehci_hcd
*ehci
,
796 struct ehci_qh
*qh
= ehci_qh_alloc (ehci
, flags
);
797 u32 info1
= 0, info2
= 0;
800 struct usb_tt
*tt
= urb
->dev
->tt
;
801 struct ehci_qh_hw
*hw
;
807 * init endpoint/device data for this QH
809 info1
|= usb_pipeendpoint (urb
->pipe
) << 8;
810 info1
|= usb_pipedevice (urb
->pipe
) << 0;
812 is_input
= usb_pipein (urb
->pipe
);
813 type
= usb_pipetype (urb
->pipe
);
814 maxp
= usb_maxpacket (urb
->dev
, urb
->pipe
, !is_input
);
816 /* 1024 byte maxpacket is a hardware ceiling. High bandwidth
817 * acts like up to 3KB, but is built from smaller packets.
819 if (max_packet(maxp
) > 1024) {
820 ehci_dbg(ehci
, "bogus qh maxpacket %d\n", max_packet(maxp
));
824 /* Compute interrupt scheduling parameters just once, and save.
825 * - allowing for high bandwidth, how many nsec/uframe are used?
826 * - split transactions need a second CSPLIT uframe; same question
827 * - splits also need a schedule gap (for full/low speed I/O)
828 * - qh has a polling interval
830 * For control/bulk requests, the HC or TT handles these.
832 if (type
== PIPE_INTERRUPT
) {
833 qh
->usecs
= NS_TO_US(usb_calc_bus_time(USB_SPEED_HIGH
,
835 hb_mult(maxp
) * max_packet(maxp
)));
836 qh
->start
= NO_FRAME
;
838 if (urb
->dev
->speed
== USB_SPEED_HIGH
) {
842 qh
->period
= urb
->interval
>> 3;
843 if (qh
->period
== 0 && urb
->interval
!= 1) {
844 /* NOTE interval 2 or 4 uframes could work.
845 * But interval 1 scheduling is simpler, and
846 * includes high bandwidth.
849 } else if (qh
->period
> ehci
->periodic_size
) {
850 qh
->period
= ehci
->periodic_size
;
851 urb
->interval
= qh
->period
<< 3;
856 /* gap is f(FS/LS transfer times) */
857 qh
->gap_uf
= 1 + usb_calc_bus_time (urb
->dev
->speed
,
858 is_input
, 0, maxp
) / (125 * 1000);
860 /* FIXME this just approximates SPLIT/CSPLIT times */
861 if (is_input
) { // SPLIT, gap, CSPLIT+DATA
862 qh
->c_usecs
= qh
->usecs
+ HS_USECS (0);
863 qh
->usecs
= HS_USECS (1);
864 } else { // SPLIT+DATA, gap, CSPLIT
865 qh
->usecs
+= HS_USECS (1);
866 qh
->c_usecs
= HS_USECS (0);
869 think_time
= tt
? tt
->think_time
: 0;
870 qh
->tt_usecs
= NS_TO_US (think_time
+
871 usb_calc_bus_time (urb
->dev
->speed
,
872 is_input
, 0, max_packet (maxp
)));
873 qh
->period
= urb
->interval
;
874 if (qh
->period
> ehci
->periodic_size
) {
875 qh
->period
= ehci
->periodic_size
;
876 urb
->interval
= qh
->period
;
881 /* support for tt scheduling, and access to toggles */
885 switch (urb
->dev
->speed
) {
887 info1
|= QH_LOW_SPEED
;
891 /* EPS 0 means "full" */
892 if (type
!= PIPE_INTERRUPT
)
893 info1
|= (EHCI_TUNE_RL_TT
<< 28);
894 if (type
== PIPE_CONTROL
) {
895 info1
|= QH_CONTROL_EP
; /* for TT */
896 info1
|= QH_TOGGLE_CTL
; /* toggle from qtd */
900 info2
|= (EHCI_TUNE_MULT_TT
<< 30);
902 /* Some Freescale processors have an erratum in which the
903 * port number in the queue head was 0..N-1 instead of 1..N.
905 if (ehci_has_fsl_portno_bug(ehci
))
906 info2
|= (urb
->dev
->ttport
-1) << 23;
908 info2
|= urb
->dev
->ttport
<< 23;
910 /* set the address of the TT; for TDI's integrated
911 * root hub tt, leave it zeroed.
913 if (tt
&& tt
->hub
!= ehci_to_hcd(ehci
)->self
.root_hub
)
914 info2
|= tt
->hub
->devnum
<< 16;
916 /* NOTE: if (PIPE_INTERRUPT) { scheduler sets c-mask } */
920 case USB_SPEED_HIGH
: /* no TT involved */
921 info1
|= QH_HIGH_SPEED
;
922 if (type
== PIPE_CONTROL
) {
923 info1
|= (EHCI_TUNE_RL_HS
<< 28);
924 info1
|= 64 << 16; /* usb2 fixed maxpacket */
925 info1
|= QH_TOGGLE_CTL
; /* toggle from qtd */
926 info2
|= (EHCI_TUNE_MULT_HS
<< 30);
927 } else if (type
== PIPE_BULK
) {
928 info1
|= (EHCI_TUNE_RL_HS
<< 28);
929 /* The USB spec says that high speed bulk endpoints
930 * always use 512 byte maxpacket. But some device
931 * vendors decided to ignore that, and MSFT is happy
932 * to help them do so. So now people expect to use
933 * such nonconformant devices with Linux too; sigh.
935 info1
|= max_packet(maxp
) << 16;
936 info2
|= (EHCI_TUNE_MULT_HS
<< 30);
937 } else { /* PIPE_INTERRUPT */
938 info1
|= max_packet (maxp
) << 16;
939 info2
|= hb_mult (maxp
) << 30;
943 ehci_dbg(ehci
, "bogus dev %p speed %d\n", urb
->dev
,
946 qh_destroy(ehci
, qh
);
950 /* NOTE: if (PIPE_INTERRUPT) { scheduler sets s-mask } */
952 /* init as live, toggle clear, advance to dummy */
953 qh
->qh_state
= QH_STATE_IDLE
;
955 hw
->hw_info1
= cpu_to_hc32(ehci
, info1
);
956 hw
->hw_info2
= cpu_to_hc32(ehci
, info2
);
957 qh
->is_out
= !is_input
;
958 usb_settoggle (urb
->dev
, usb_pipeendpoint (urb
->pipe
), !is_input
, 1);
959 qh_refresh (ehci
, qh
);
963 /*-------------------------------------------------------------------------*/
965 static void enable_async(struct ehci_hcd
*ehci
)
967 if (ehci
->async_count
++)
970 /* Stop waiting to turn off the async schedule */
971 ehci
->enabled_hrtimer_events
&= ~BIT(EHCI_HRTIMER_DISABLE_ASYNC
);
973 /* Don't start the schedule until ASS is 0 */
975 turn_on_io_watchdog(ehci
);
978 static void disable_async(struct ehci_hcd
*ehci
)
980 if (--ehci
->async_count
)
983 /* The async schedule and async_unlink list are supposed to be empty */
984 WARN_ON(ehci
->async
->qh_next
.qh
|| ehci
->async_unlink
);
986 /* Don't turn off the schedule until ASS is 1 */
990 /* move qh (and its qtds) onto async queue; maybe enable queue. */
992 static void qh_link_async (struct ehci_hcd
*ehci
, struct ehci_qh
*qh
)
994 __hc32 dma
= QH_NEXT(ehci
, qh
->qh_dma
);
995 struct ehci_qh
*head
;
997 /* Don't link a QH if there's a Clear-TT-Buffer pending */
998 if (unlikely(qh
->clearing_tt
))
1001 WARN_ON(qh
->qh_state
!= QH_STATE_IDLE
);
1003 /* clear halt and/or toggle; and maybe recover from silicon quirk */
1004 qh_refresh(ehci
, qh
);
1006 /* splice right after start */
1008 qh
->qh_next
= head
->qh_next
;
1009 qh
->hw
->hw_next
= head
->hw
->hw_next
;
1012 head
->qh_next
.qh
= qh
;
1013 head
->hw
->hw_next
= dma
;
1016 qh
->qh_state
= QH_STATE_LINKED
;
1017 /* qtd completions reported later by interrupt */
1022 /*-------------------------------------------------------------------------*/
1025 * For control/bulk/interrupt, return QH with these TDs appended.
1026 * Allocates and initializes the QH if necessary.
1027 * Returns null if it can't allocate a QH it needs to.
1028 * If the QH has TDs (urbs) already, that's great.
1030 static struct ehci_qh
*qh_append_tds (
1031 struct ehci_hcd
*ehci
,
1033 struct list_head
*qtd_list
,
1038 struct ehci_qh
*qh
= NULL
;
1039 __hc32 qh_addr_mask
= cpu_to_hc32(ehci
, 0x7f);
1041 qh
= (struct ehci_qh
*) *ptr
;
1042 if (unlikely (qh
== NULL
)) {
1043 /* can't sleep here, we have ehci->lock... */
1044 qh
= qh_make (ehci
, urb
, GFP_ATOMIC
);
1047 if (likely (qh
!= NULL
)) {
1048 struct ehci_qtd
*qtd
;
1050 if (unlikely (list_empty (qtd_list
)))
1053 qtd
= list_entry (qtd_list
->next
, struct ehci_qtd
,
1056 /* control qh may need patching ... */
1057 if (unlikely (epnum
== 0)) {
1059 /* usb_reset_device() briefly reverts to address 0 */
1060 if (usb_pipedevice (urb
->pipe
) == 0)
1061 qh
->hw
->hw_info1
&= ~qh_addr_mask
;
1064 /* just one way to queue requests: swap with the dummy qtd.
1065 * only hc or qh_refresh() ever modify the overlay.
1067 if (likely (qtd
!= NULL
)) {
1068 struct ehci_qtd
*dummy
;
1072 /* to avoid racing the HC, use the dummy td instead of
1073 * the first td of our list (becomes new dummy). both
1074 * tds stay deactivated until we're done, when the
1075 * HC is allowed to fetch the old dummy (4.10.2).
1077 token
= qtd
->hw_token
;
1078 qtd
->hw_token
= HALT_BIT(ehci
);
1082 dma
= dummy
->qtd_dma
;
1084 dummy
->qtd_dma
= dma
;
1086 list_del (&qtd
->qtd_list
);
1087 list_add (&dummy
->qtd_list
, qtd_list
);
1088 list_splice_tail(qtd_list
, &qh
->qtd_list
);
1090 ehci_qtd_init(ehci
, qtd
, qtd
->qtd_dma
);
1093 /* hc must see the new dummy at list end */
1095 qtd
= list_entry (qh
->qtd_list
.prev
,
1096 struct ehci_qtd
, qtd_list
);
1097 qtd
->hw_next
= QTD_NEXT(ehci
, dma
);
1099 /* let the hc process these next qtds */
1101 dummy
->hw_token
= token
;
1109 /*-------------------------------------------------------------------------*/
1113 struct ehci_hcd
*ehci
,
1115 struct list_head
*qtd_list
,
1119 unsigned long flags
;
1120 struct ehci_qh
*qh
= NULL
;
1123 epnum
= urb
->ep
->desc
.bEndpointAddress
;
1125 #ifdef EHCI_URB_TRACE
1127 struct ehci_qtd
*qtd
;
1128 qtd
= list_entry(qtd_list
->next
, struct ehci_qtd
, qtd_list
);
1130 "%s %s urb %p ep%d%s len %d, qtd %p [qh %p]\n",
1131 __func__
, urb
->dev
->devpath
, urb
,
1132 epnum
& 0x0f, (epnum
& USB_DIR_IN
) ? "in" : "out",
1133 urb
->transfer_buffer_length
,
1134 qtd
, urb
->ep
->hcpriv
);
1138 spin_lock_irqsave (&ehci
->lock
, flags
);
1139 if (unlikely(!HCD_HW_ACCESSIBLE(ehci_to_hcd(ehci
)))) {
1143 rc
= usb_hcd_link_urb_to_ep(ehci_to_hcd(ehci
), urb
);
1147 qh
= qh_append_tds(ehci
, urb
, qtd_list
, epnum
, &urb
->ep
->hcpriv
);
1148 if (unlikely(qh
== NULL
)) {
1149 usb_hcd_unlink_urb_from_ep(ehci_to_hcd(ehci
), urb
);
1154 /* Control/bulk operations through TTs don't need scheduling,
1155 * the HC and TT handle it when the TT has a buffer ready.
1157 if (likely (qh
->qh_state
== QH_STATE_IDLE
))
1158 qh_link_async(ehci
, qh
);
1160 spin_unlock_irqrestore (&ehci
->lock
, flags
);
1161 if (unlikely (qh
== NULL
))
1162 qtd_list_free (ehci
, urb
, qtd_list
);
1166 /*-------------------------------------------------------------------------*/
1168 static void single_unlink_async(struct ehci_hcd
*ehci
, struct ehci_qh
*qh
)
1170 struct ehci_qh
*prev
;
1172 /* Add to the end of the list of QHs waiting for the next IAAD */
1173 qh
->qh_state
= QH_STATE_UNLINK
;
1174 if (ehci
->async_unlink
)
1175 ehci
->async_unlink_last
->unlink_next
= qh
;
1177 ehci
->async_unlink
= qh
;
1178 ehci
->async_unlink_last
= qh
;
1180 /* Unlink it from the schedule */
1182 while (prev
->qh_next
.qh
!= qh
)
1183 prev
= prev
->qh_next
.qh
;
1185 prev
->hw
->hw_next
= qh
->hw
->hw_next
;
1186 prev
->qh_next
= qh
->qh_next
;
1187 if (ehci
->qh_scan_next
== qh
)
1188 ehci
->qh_scan_next
= qh
->qh_next
.qh
;
1191 static void start_iaa_cycle(struct ehci_hcd
*ehci
, bool nested
)
1194 * Do nothing if an IAA cycle is already running or
1195 * if one will be started shortly.
1197 if (ehci
->async_iaa
|| ehci
->async_unlinking
)
1200 /* If the controller isn't running, we don't have to wait for it */
1201 if (unlikely(ehci
->rh_state
< EHCI_RH_RUNNING
)) {
1203 /* Do all the waiting QHs */
1204 ehci
->async_iaa
= ehci
->async_unlink
;
1205 ehci
->async_unlink
= NULL
;
1207 if (!nested
) /* Avoid recursion */
1208 end_unlink_async(ehci
);
1210 /* Otherwise start a new IAA cycle */
1211 } else if (likely(ehci
->rh_state
== EHCI_RH_RUNNING
)) {
1214 /* Do only the first waiting QH (nVidia bug?) */
1215 qh
= ehci
->async_unlink
;
1216 ehci
->async_iaa
= qh
;
1217 ehci
->async_unlink
= qh
->unlink_next
;
1218 qh
->unlink_next
= NULL
;
1220 /* Make sure the unlinks are all visible to the hardware */
1223 ehci_writel(ehci
, ehci
->command
| CMD_IAAD
,
1224 &ehci
->regs
->command
);
1225 ehci_readl(ehci
, &ehci
->regs
->command
);
1226 ehci_enable_event(ehci
, EHCI_HRTIMER_IAA_WATCHDOG
, true);
1230 /* the async qh for the qtds being unlinked are now gone from the HC */
1232 static void end_unlink_async(struct ehci_hcd
*ehci
)
1236 if (ehci
->has_synopsys_hc_bug
)
1237 ehci_writel(ehci
, (u32
) ehci
->async
->qh_dma
,
1238 &ehci
->regs
->async_next
);
1240 /* Process the idle QHs */
1242 ehci
->async_unlinking
= true;
1243 while (ehci
->async_iaa
) {
1244 qh
= ehci
->async_iaa
;
1245 ehci
->async_iaa
= qh
->unlink_next
;
1246 qh
->unlink_next
= NULL
;
1248 qh
->qh_state
= QH_STATE_IDLE
;
1249 qh
->qh_next
.qh
= NULL
;
1251 qh_completions(ehci
, qh
);
1252 if (!list_empty(&qh
->qtd_list
) &&
1253 ehci
->rh_state
== EHCI_RH_RUNNING
)
1254 qh_link_async(ehci
, qh
);
1255 disable_async(ehci
);
1257 ehci
->async_unlinking
= false;
1259 /* Start a new IAA cycle if any QHs are waiting for it */
1260 if (ehci
->async_unlink
) {
1261 start_iaa_cycle(ehci
, true);
1262 if (unlikely(ehci
->rh_state
< EHCI_RH_RUNNING
))
1267 static void start_unlink_async(struct ehci_hcd
*ehci
, struct ehci_qh
*qh
);
1269 static void unlink_empty_async(struct ehci_hcd
*ehci
)
1272 struct ehci_qh
*qh_to_unlink
= NULL
;
1273 bool check_unlinks_later
= false;
1276 /* Find the last async QH which has been empty for a timer cycle */
1277 for (qh
= ehci
->async
->qh_next
.qh
; qh
; qh
= qh
->qh_next
.qh
) {
1278 if (list_empty(&qh
->qtd_list
) &&
1279 qh
->qh_state
== QH_STATE_LINKED
) {
1281 if (qh
->unlink_cycle
== ehci
->async_unlink_cycle
)
1282 check_unlinks_later
= true;
1288 /* If nothing else is being unlinked, unlink the last empty QH */
1289 if (!ehci
->async_iaa
&& !ehci
->async_unlink
&& qh_to_unlink
) {
1290 start_unlink_async(ehci
, qh_to_unlink
);
1294 /* Other QHs will be handled later */
1296 ehci_enable_event(ehci
, EHCI_HRTIMER_ASYNC_UNLINKS
, true);
1297 ++ehci
->async_unlink_cycle
;
1301 /* makes sure the async qh will become idle */
1302 /* caller must own ehci->lock */
1304 static void start_unlink_async(struct ehci_hcd
*ehci
, struct ehci_qh
*qh
)
1307 * If the QH isn't linked then there's nothing we can do
1308 * unless we were called during a giveback, in which case
1309 * qh_completions() has to deal with it.
1311 if (qh
->qh_state
!= QH_STATE_LINKED
) {
1312 if (qh
->qh_state
== QH_STATE_COMPLETING
)
1313 qh
->needs_rescan
= 1;
1317 single_unlink_async(ehci
, qh
);
1318 start_iaa_cycle(ehci
, false);
1321 /*-------------------------------------------------------------------------*/
1323 static void scan_async (struct ehci_hcd
*ehci
)
1326 bool check_unlinks_later
= false;
1328 ehci
->qh_scan_next
= ehci
->async
->qh_next
.qh
;
1329 while (ehci
->qh_scan_next
) {
1330 qh
= ehci
->qh_scan_next
;
1331 ehci
->qh_scan_next
= qh
->qh_next
.qh
;
1333 /* clean any finished work for this qh */
1334 if (!list_empty(&qh
->qtd_list
)) {
1338 * Unlinks could happen here; completion reporting
1339 * drops the lock. That's why ehci->qh_scan_next
1340 * always holds the next qh to scan; if the next qh
1341 * gets unlinked then ehci->qh_scan_next is adjusted
1342 * in single_unlink_async().
1344 temp
= qh_completions(ehci
, qh
);
1345 if (qh
->needs_rescan
) {
1346 start_unlink_async(ehci
, qh
);
1347 } else if (list_empty(&qh
->qtd_list
)
1348 && qh
->qh_state
== QH_STATE_LINKED
) {
1349 qh
->unlink_cycle
= ehci
->async_unlink_cycle
;
1350 check_unlinks_later
= true;
1351 } else if (temp
!= 0)
1357 * Unlink empty entries, reducing DMA usage as well
1358 * as HCD schedule-scanning costs. Delay for any qh
1359 * we just scanned, there's a not-unusual case that it
1360 * doesn't stay idle for long.
1362 if (check_unlinks_later
&& ehci
->rh_state
== EHCI_RH_RUNNING
&&
1363 !(ehci
->enabled_hrtimer_events
&
1364 BIT(EHCI_HRTIMER_ASYNC_UNLINKS
))) {
1365 ehci_enable_event(ehci
, EHCI_HRTIMER_ASYNC_UNLINKS
, true);
1366 ++ehci
->async_unlink_cycle
;