2 * Copyright (c) 2001-2002 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_qtd *qtd, dma_addr_t buf, size_t len,
47 int token, int maxpacket)
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 */
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_le32 ((u32)addr);
66 qtd->hw_buf_hi [i] = cpu_to_le32 ((u32)(addr >> 32));
68 if ((count + 0x1000) < len)
74 /* short packets may only terminate transfers */
76 count -= (count % maxpacket);
78 qtd->hw_token = cpu_to_le32 ((count << 16) | token);
84 /*-------------------------------------------------------------------------*/
86 /* update halted (but potentially linked) qh */
89 qh_update (struct ehci_hcd *ehci, struct ehci_qh *qh, struct ehci_qtd *qtd)
91 qh->hw_qtd_next = QTD_NEXT (qtd->qtd_dma);
92 qh->hw_alt_next = EHCI_LIST_END;
94 /* HC must see latest qtd and qh data before we clear ACTIVE+HALT */
96 qh->hw_token &= __constant_cpu_to_le32 (QTD_TOGGLE | QTD_STS_PING);
99 /*-------------------------------------------------------------------------*/
101 static void qtd_copy_status (
102 struct ehci_hcd *ehci,
108 /* count IN/OUT bytes, not SETUP (even short packets) */
109 if (likely (QTD_PID (token) != 2))
110 urb->actual_length += length - QTD_LENGTH (token);
112 /* don't modify error codes */
113 if (unlikely (urb->status != -EINPROGRESS))
116 /* force cleanup after short read; not always an error */
117 if (unlikely (IS_SHORT_READ (token)))
118 urb->status = -EREMOTEIO;
120 /* serious "can't proceed" faults reported by the hardware */
121 if (token & QTD_STS_HALT) {
122 if (token & QTD_STS_BABBLE) {
123 /* FIXME "must" disable babbling device's port too */
124 urb->status = -EOVERFLOW;
125 } else if (token & QTD_STS_MMF) {
126 /* fs/ls interrupt xfer missed the complete-split */
127 urb->status = -EPROTO;
128 } else if (token & QTD_STS_DBE) {
129 urb->status = (QTD_PID (token) == 1) /* IN ? */
130 ? -ENOSR /* hc couldn't read data */
131 : -ECOMM; /* hc couldn't write data */
132 } else if (token & QTD_STS_XACT) {
133 /* timeout, bad crc, wrong PID, etc; retried */
134 if (QTD_CERR (token))
135 urb->status = -EPIPE;
137 ehci_dbg (ehci, "devpath %s ep%d%s 3strikes\n",
139 usb_pipeendpoint (urb->pipe),
140 usb_pipein (urb->pipe) ? "in" : "out");
141 urb->status = -EPROTO;
143 /* CERR nonzero + no errors + halt --> stall */
144 } else if (QTD_CERR (token))
145 urb->status = -EPIPE;
147 urb->status = -EPROTO;
150 "dev%d ep%d%s qtd token %08x --> status %d\n",
151 usb_pipedevice (urb->pipe),
152 usb_pipeendpoint (urb->pipe),
153 usb_pipein (urb->pipe) ? "in" : "out",
156 /* stall indicates some recovery action is needed */
157 if (urb->status == -EPIPE) {
158 int pipe = urb->pipe;
160 if (!usb_pipecontrol (pipe))
161 usb_endpoint_halt (urb->dev,
162 usb_pipeendpoint (pipe),
165 /* if async CSPLIT failed, try cleaning out the TT buffer */
166 } else if (urb->dev->tt && !usb_pipeint (urb->pipe)
167 && ((token & QTD_STS_MMF) != 0
168 || QTD_CERR(token) == 0)
169 && (!ehci_is_ARC(ehci)
170 || urb->dev->tt->hub !=
171 ehci->hcd.self.root_hub)) {
173 struct usb_device *tt = urb->dev->tt->hub;
175 "clear tt buffer port %d, a%d ep%d t%08x\n",
176 urb->dev->ttport, urb->dev->devnum,
177 usb_pipeendpoint (urb->pipe), token);
179 usb_hub_tt_clear_buffer (urb->dev, urb->pipe);
185 ehci_urb_done (struct ehci_hcd *ehci, struct urb *urb, struct pt_regs *regs)
187 if (likely (urb->hcpriv != 0)) {
188 struct ehci_qh *qh = (struct ehci_qh *) urb->hcpriv;
190 /* S-mask in a QH means it's an interrupt urb */
191 if ((qh->hw_info2 & __constant_cpu_to_le32 (0x00ff)) != 0) {
193 /* ... update hc-wide periodic stats (for usbfs) */
194 hcd_to_bus (&ehci->hcd)->bandwidth_int_reqs--;
199 spin_lock (&urb->lock);
201 switch (urb->status) {
202 case -EINPROGRESS: /* success */
205 COUNT (ehci->stats.complete);
207 case -EREMOTEIO: /* fault or normal */
208 if (!(urb->transfer_flags & URB_SHORT_NOT_OK))
210 COUNT (ehci->stats.complete);
212 case -ECONNRESET: /* canceled */
214 COUNT (ehci->stats.unlink);
217 spin_unlock (&urb->lock);
219 #ifdef EHCI_URB_TRACE
221 "%s %s urb %p ep%d%s status %d len %d/%d\n",
222 __FUNCTION__, urb->dev->devpath, urb,
223 usb_pipeendpoint (urb->pipe),
224 usb_pipein (urb->pipe) ? "in" : "out",
226 urb->actual_length, urb->transfer_buffer_length);
229 /* complete() can reenter this HCD */
230 spin_unlock (&ehci->lock);
231 usb_hcd_giveback_urb (&ehci->hcd, urb, regs);
232 spin_lock (&ehci->lock);
237 * Process and free completed qtds for a qh, returning URBs to drivers.
238 * Chases up to qh->hw_current. Returns number of completions called,
239 * indicating how much "real" work we did.
241 #define HALT_BIT __constant_cpu_to_le32(QTD_STS_HALT)
243 qh_completions (struct ehci_hcd *ehci, struct ehci_qh *qh, struct pt_regs *regs)
245 struct ehci_qtd *last = NULL, *end = qh->dummy;
246 struct list_head *entry, *tmp;
252 if (unlikely (list_empty (&qh->qtd_list)))
255 /* completions (or tasks on other cpus) must never clobber HALT
256 * till we've gone through and cleaned everything up, even when
257 * they add urbs to this qh's queue or mark them for unlinking.
259 * NOTE: unlinking expects to be done in queue order.
261 state = qh->qh_state;
262 qh->qh_state = QH_STATE_COMPLETING;
263 stopped = (state == QH_STATE_IDLE);
265 /* remove de-activated QTDs from front of queue.
266 * after faults (including short reads), cleanup this urb
267 * then let the queue advance.
268 * if queue is stopped, handles unlinks.
270 list_for_each_safe (entry, tmp, &qh->qtd_list) {
271 struct ehci_qtd *qtd;
275 qtd = list_entry (entry, struct ehci_qtd, qtd_list);
278 /* clean up any state from previous QTD ...*/
280 if (likely (last->urb != urb)) {
281 ehci_urb_done (ehci, last->urb, regs);
284 ehci_qtd_free (ehci, last);
288 /* ignore urbs submitted during completions we reported */
292 /* hardware copies qtd out of qh overlay */
294 token = le32_to_cpu (qtd->hw_token);
296 /* always clean up qtds the hc de-activated */
297 if ((token & QTD_STS_ACTIVE) == 0) {
299 if ((token & QTD_STS_HALT) != 0) {
302 /* magic dummy for some short reads; qh won't advance */
303 } else if (IS_SHORT_READ (token)
304 && (qh->hw_alt_next & QTD_MASK)
305 == ehci->async->hw_alt_next) {
310 /* stop scanning when we reach qtds the hc is using */
311 } else if (likely (!stopped
312 && HCD_IS_RUNNING (ehci->hcd.state))) {
318 /* ignore active urbs unless some previous qtd
319 * for the urb faulted (including short read) or
320 * its urb was canceled. we may patch qh or qtds.
322 if (likely (urb->status == -EINPROGRESS))
325 /* issue status after short control reads */
326 if (unlikely (do_status != 0)
327 && QTD_PID (token) == 0 /* OUT */) {
332 /* token in overlay may be most current */
333 if (state == QH_STATE_IDLE
334 && cpu_to_le32 (qtd->qtd_dma)
336 token = le32_to_cpu (qh->hw_token);
338 /* force halt for unlinked or blocked qh, so we'll
339 * patch the qh later and so that completions can't
340 * activate it while we "know" it's stopped.
342 if ((HALT_BIT & qh->hw_token) == 0) {
344 qh->hw_token |= HALT_BIT;
349 /* remove it from the queue */
350 spin_lock (&urb->lock);
351 qtd_copy_status (ehci, urb, qtd->length, token);
352 do_status = (urb->status == -EREMOTEIO)
353 && usb_pipecontrol (urb->pipe);
354 spin_unlock (&urb->lock);
356 if (stopped && qtd->qtd_list.prev != &qh->qtd_list) {
357 last = list_entry (qtd->qtd_list.prev,
358 struct ehci_qtd, qtd_list);
359 last->hw_next = qtd->hw_next;
361 list_del (&qtd->qtd_list);
365 /* last urb's completion might still need calling */
366 if (likely (last != 0)) {
367 ehci_urb_done (ehci, last->urb, regs);
369 ehci_qtd_free (ehci, last);
372 /* restore original state; caller must unlink or relink */
373 qh->qh_state = state;
375 /* update qh after fault cleanup */
376 if (unlikely (stopped != 0)
377 /* some EHCI 0.95 impls will overlay dummy qtds */
378 || qh->hw_qtd_next == EHCI_LIST_END) {
379 if (list_empty (&qh->qtd_list))
382 end = list_entry (qh->qtd_list.next,
383 struct ehci_qtd, qtd_list);
384 /* first qtd may already be partially processed */
385 if (cpu_to_le32 (end->qtd_dma) == qh->hw_current)
389 qh_update (ehci, qh, end);
395 /*-------------------------------------------------------------------------*/
397 // high bandwidth multiplier, as encoded in highspeed endpoint descriptors
398 #define hb_mult(wMaxPacketSize) (1 + (((wMaxPacketSize) >> 11) & 0x03))
399 // ... and packet size, for any kind of endpoint descriptor
400 #define max_packet(wMaxPacketSize) ((wMaxPacketSize) & 0x07ff)
403 * reverse of qh_urb_transaction: free a list of TDs.
404 * used for cleanup after errors, before HC sees an URB's TDs.
406 static void qtd_list_free (
407 struct ehci_hcd *ehci,
409 struct list_head *qtd_list
411 struct list_head *entry, *temp;
413 list_for_each_safe (entry, temp, qtd_list) {
414 struct ehci_qtd *qtd;
416 qtd = list_entry (entry, struct ehci_qtd, qtd_list);
417 list_del (&qtd->qtd_list);
418 ehci_qtd_free (ehci, qtd);
423 * create a list of filled qtds for this URB; won't link into qh.
425 static struct list_head *
427 struct ehci_hcd *ehci,
429 struct list_head *head,
432 struct ehci_qtd *qtd, *qtd_prev;
439 * URBs map to sequences of QTDs: one logical transaction
441 qtd = ehci_qtd_alloc (ehci, flags);
444 list_add_tail (&qtd->qtd_list, head);
447 token = QTD_STS_ACTIVE;
448 token |= (EHCI_TUNE_CERR << 10);
449 /* for split transactions, SplitXState initialized to zero */
451 len = urb->transfer_buffer_length;
452 is_input = usb_pipein (urb->pipe);
453 if (usb_pipecontrol (urb->pipe)) {
455 qtd_fill (qtd, urb->setup_dma, sizeof (struct usb_ctrlrequest),
456 token | (2 /* "setup" */ << 8), 8);
458 /* ... and always at least one more pid */
461 qtd = ehci_qtd_alloc (ehci, flags);
465 qtd_prev->hw_next = QTD_NEXT (qtd->qtd_dma);
466 list_add_tail (&qtd->qtd_list, head);
470 * data transfer stage: buffer setup
472 if (likely (len > 0))
473 buf = urb->transfer_dma;
477 // FIXME this 'buf' check break some zlps...
478 if (!buf || is_input)
479 token |= (1 /* "in" */ << 8);
480 /* else it's already initted to "out" pid (0 << 8) */
482 maxpacket = max_packet(usb_maxpacket(urb->dev, urb->pipe, !is_input));
485 * buffer gets wrapped in one or more qtds;
486 * last one may be "short" (including zero len)
487 * and may serve as a control status ack
492 this_qtd_len = qtd_fill (qtd, buf, len, token, maxpacket);
496 qtd->hw_alt_next = ehci->async->hw_alt_next;
498 /* qh makes control packets use qtd toggle; maybe switch it */
499 if ((maxpacket & (this_qtd_len + (maxpacket - 1))) == 0)
502 if (likely (len <= 0))
506 qtd = ehci_qtd_alloc (ehci, flags);
510 qtd_prev->hw_next = QTD_NEXT (qtd->qtd_dma);
511 list_add_tail (&qtd->qtd_list, head);
514 /* unless the bulk/interrupt caller wants a chance to clean
515 * up after short reads, hc should advance qh past this urb
517 if (likely ((urb->transfer_flags & URB_SHORT_NOT_OK) == 0
518 || usb_pipecontrol (urb->pipe)))
519 qtd->hw_alt_next = EHCI_LIST_END;
522 * control requests may need a terminating data "status" ack;
523 * bulk ones may need a terminating short packet (zero length).
525 if (likely (buf != 0)) {
528 if (usb_pipecontrol (urb->pipe)) {
530 token ^= 0x0100; /* "in" <--> "out" */
531 token |= QTD_TOGGLE; /* force DATA1 */
532 } else if (usb_pipebulk (urb->pipe)
533 && (urb->transfer_flags & URB_ZERO_PACKET)
534 && !(urb->transfer_buffer_length % maxpacket)) {
539 qtd = ehci_qtd_alloc (ehci, flags);
543 qtd_prev->hw_next = QTD_NEXT (qtd->qtd_dma);
544 list_add_tail (&qtd->qtd_list, head);
546 /* never any data in such packets */
547 qtd_fill (qtd, 0, 0, token, 0);
551 /* by default, enable interrupt on urb completion */
552 if (likely (!(urb->transfer_flags & URB_NO_INTERRUPT)))
553 qtd->hw_token |= __constant_cpu_to_le32 (QTD_IOC);
557 qtd_list_free (ehci, urb, head);
561 /*-------------------------------------------------------------------------*/
564 * Hardware maintains data toggle (like OHCI) ... here we (re)initialize
565 * the hardware data toggle in the QH, and set the pseudo-toggle in udev
566 * so we can see if usb_clear_halt() was called. NOP for control, since
567 * we set up qh->hw_info1 to always use the QTD toggle bits.
570 clear_toggle (struct usb_device *udev, int ep, int is_out, struct ehci_qh *qh)
572 vdbg ("clear toggle, dev %d ep 0x%x-%s",
573 udev->devnum, ep, is_out ? "out" : "in");
574 qh->hw_token &= ~__constant_cpu_to_le32 (QTD_TOGGLE);
575 usb_settoggle (udev, ep, is_out, 1);
578 // Would be best to create all qh's from config descriptors,
579 // when each interface/altsetting is established. Unlink
580 // any previous qh and cancel its urbs first; endpoints are
581 // implicitly reset then (data toggle too).
582 // That'd mean updating how usbcore talks to HCDs. (2.7?)
586 * Each QH holds a qtd list; a QH is used for everything except iso.
588 * For interrupt urbs, the scheduler must set the microframe scheduling
589 * mask(s) each time the QH gets scheduled. For highspeed, that's
590 * just one microframe in the s-mask. For split interrupt transactions
591 * there are additional complications: c-mask, maybe FSTNs.
593 static struct ehci_qh *
595 struct ehci_hcd *ehci,
599 struct ehci_qh *qh = ehci_qh_alloc (ehci, flags);
600 u32 info1 = 0, info2 = 0;
608 * init endpoint/device data for this QH
610 info1 |= usb_pipeendpoint (urb->pipe) << 8;
611 info1 |= usb_pipedevice (urb->pipe) << 0;
613 is_input = usb_pipein (urb->pipe);
614 type = usb_pipetype (urb->pipe);
615 maxp = usb_maxpacket (urb->dev, urb->pipe, !is_input);
617 /* Compute interrupt scheduling parameters just once, and save.
618 * - allowing for high bandwidth, how many nsec/uframe are used?
619 * - split transactions need a second CSPLIT uframe; same question
620 * - splits also need a schedule gap (for full/low speed I/O)
621 * - qh has a polling interval
623 * For control/bulk requests, the HC or TT handles these.
625 if (type == PIPE_INTERRUPT) {
626 qh->usecs = usb_calc_bus_time (USB_SPEED_HIGH, is_input, 0,
627 hb_mult (maxp) * max_packet (maxp));
628 qh->start = NO_FRAME;
630 if (urb->dev->speed == USB_SPEED_HIGH) {
634 /* FIXME handle HS periods of less than 1 frame. */
635 qh->period = urb->interval >> 3;
636 if (qh->period < 1) {
637 dbg ("intr period %d uframes, NYET!",
642 /* gap is f(FS/LS transfer times) */
643 qh->gap_uf = 1 + usb_calc_bus_time (urb->dev->speed,
644 is_input, 0, maxp) / (125 * 1000);
646 /* FIXME this just approximates SPLIT/CSPLIT times */
647 if (is_input) { // SPLIT, gap, CSPLIT+DATA
648 qh->c_usecs = qh->usecs + HS_USECS (0);
649 qh->usecs = HS_USECS (1);
650 } else { // SPLIT+DATA, gap, CSPLIT
651 qh->usecs += HS_USECS (1);
652 qh->c_usecs = HS_USECS (0);
655 qh->period = urb->interval;
658 /* support for tt scheduling */
659 qh->dev = usb_get_dev (urb->dev);
663 switch (urb->dev->speed) {
665 info1 |= (1 << 12); /* EPS "low" */
669 /* EPS 0 means "full" */
670 if (type != PIPE_INTERRUPT)
671 info1 |= (EHCI_TUNE_RL_TT << 28);
672 if (type == PIPE_CONTROL) {
673 info1 |= (1 << 27); /* for TT */
674 info1 |= 1 << 14; /* toggle from qtd */
678 info2 |= (EHCI_TUNE_MULT_TT << 30);
679 info2 |= urb->dev->ttport << 23;
681 /* set the address of the TT; for ARC's integrated
682 * root hub tt, leave it zeroed.
684 if (!ehci_is_ARC(ehci)
685 || urb->dev->tt->hub != ehci->hcd.self.root_hub)
686 info2 |= urb->dev->tt->hub->devnum << 16;
688 /* NOTE: if (PIPE_INTERRUPT) { scheduler sets c-mask } */
692 case USB_SPEED_HIGH: /* no TT involved */
693 info1 |= (2 << 12); /* EPS "high" */
694 if (type == PIPE_CONTROL) {
695 info1 |= (EHCI_TUNE_RL_HS << 28);
696 info1 |= 64 << 16; /* usb2 fixed maxpacket */
697 info1 |= 1 << 14; /* toggle from qtd */
698 info2 |= (EHCI_TUNE_MULT_HS << 30);
699 } else if (type == PIPE_BULK) {
700 info1 |= (EHCI_TUNE_RL_HS << 28);
701 info1 |= 512 << 16; /* usb2 fixed maxpacket */
702 info2 |= (EHCI_TUNE_MULT_HS << 30);
703 } else { /* PIPE_INTERRUPT */
704 info1 |= max_packet (maxp) << 16;
705 info2 |= hb_mult (maxp) << 30;
709 dbg ("bogus dev %p speed %d", urb->dev, urb->dev->speed);
715 /* NOTE: if (PIPE_INTERRUPT) { scheduler sets s-mask } */
717 /* init as live, toggle clear, advance to dummy */
718 qh->qh_state = QH_STATE_IDLE;
719 qh->hw_info1 = cpu_to_le32 (info1);
720 qh->hw_info2 = cpu_to_le32 (info2);
721 qh_update (ehci, qh, qh->dummy);
722 usb_settoggle (urb->dev, usb_pipeendpoint (urb->pipe), !is_input, 1);
726 /*-------------------------------------------------------------------------*/
728 /* move qh (and its qtds) onto async queue; maybe enable queue. */
730 static void qh_link_async (struct ehci_hcd *ehci, struct ehci_qh *qh)
732 u32 dma = QH_NEXT (qh->qh_dma);
733 struct ehci_qh *head;
735 /* (re)start the async schedule? */
737 timer_action_done (ehci, TIMER_ASYNC_OFF);
738 if (!head->qh_next.qh) {
739 u32 cmd = readl (&ehci->regs->command);
741 if (!(cmd & CMD_ASE)) {
742 /* in case a clear of CMD_ASE didn't take yet */
743 (void) handshake (&ehci->regs->status, STS_ASS, 0, 150);
744 cmd |= CMD_ASE | CMD_RUN;
745 writel (cmd, &ehci->regs->command);
746 ehci->hcd.state = USB_STATE_RUNNING;
747 /* posted write need not be known to HC yet ... */
751 qh->hw_token &= ~HALT_BIT;
753 /* splice right after start */
754 qh->qh_next = head->qh_next;
755 qh->hw_next = head->hw_next;
758 head->qh_next.qh = qh;
761 qh->qh_state = QH_STATE_LINKED;
762 /* qtd completions reported later by interrupt */
765 /*-------------------------------------------------------------------------*/
767 #define QH_ADDR_MASK __constant_le32_to_cpu(0x7f)
770 * For control/bulk/interrupt, return QH with these TDs appended.
771 * Allocates and initializes the QH if necessary.
772 * Returns null if it can't allocate a QH it needs to.
773 * If the QH has TDs (urbs) already, that's great.
775 static struct ehci_qh *qh_append_tds (
776 struct ehci_hcd *ehci,
778 struct list_head *qtd_list,
783 struct ehci_qh *qh = NULL;
785 qh = (struct ehci_qh *) *ptr;
786 if (unlikely (qh == NULL)) {
787 /* can't sleep here, we have ehci->lock... */
788 qh = qh_make (ehci, urb, GFP_ATOMIC);
791 if (likely (qh != NULL)) {
792 struct ehci_qtd *qtd;
794 if (unlikely (list_empty (qtd_list)))
797 qtd = list_entry (qtd_list->next, struct ehci_qtd,
800 /* control qh may need patching after enumeration */
801 if (unlikely (epnum == 0)) {
802 /* set_address changes the address */
803 if ((qh->hw_info1 & QH_ADDR_MASK) == 0)
804 qh->hw_info1 |= cpu_to_le32 (
805 usb_pipedevice (urb->pipe));
807 /* for full speed, ep0 maxpacket can grow */
808 else if (!(qh->hw_info1
809 & __constant_cpu_to_le32 (0x3 << 12))) {
812 info = le32_to_cpu (qh->hw_info1);
813 max = urb->dev->descriptor.bMaxPacketSize0;
814 if (max > (0x07ff & (info >> 16))) {
815 info &= ~(0x07ff << 16);
817 qh->hw_info1 = cpu_to_le32 (info);
821 /* usb_reset_device() briefly reverts to address 0 */
822 if (usb_pipedevice (urb->pipe) == 0)
823 qh->hw_info1 &= ~QH_ADDR_MASK;
826 /* usb_clear_halt() means qh data toggle gets reset */
827 if (unlikely (!usb_gettoggle (urb->dev,
828 (epnum & 0x0f), !(epnum & 0x10)))
829 && !usb_pipecontrol (urb->pipe)) {
830 /* "never happens": drivers do stall cleanup right */
831 if (qh->qh_state != QH_STATE_IDLE
832 && !list_empty (&qh->qtd_list)
833 && qh->qh_state != QH_STATE_COMPLETING)
834 ehci_warn (ehci, "clear toggle dev%d "
835 "ep%d%s: not idle\n",
836 usb_pipedevice (urb->pipe),
838 usb_pipein (urb->pipe)
840 /* else we know this overlay write is safe */
841 clear_toggle (urb->dev,
842 epnum & 0x0f, !(epnum & 0x10), qh);
845 /* just one way to queue requests: swap with the dummy qtd.
846 * only hc or qh_completions() usually modify the overlay.
848 if (likely (qtd != 0)) {
849 struct ehci_qtd *dummy;
853 /* to avoid racing the HC, use the dummy td instead of
854 * the first td of our list (becomes new dummy). both
855 * tds stay deactivated until we're done, when the
856 * HC is allowed to fetch the old dummy (4.10.2).
858 token = qtd->hw_token;
859 qtd->hw_token = HALT_BIT;
863 dma = dummy->qtd_dma;
865 dummy->qtd_dma = dma;
867 list_del (&qtd->qtd_list);
868 list_add (&dummy->qtd_list, qtd_list);
869 __list_splice (qtd_list, qh->qtd_list.prev);
871 ehci_qtd_init (qtd, qtd->qtd_dma);
874 /* hc must see the new dummy at list end */
876 qtd = list_entry (qh->qtd_list.prev,
877 struct ehci_qtd, qtd_list);
878 qtd->hw_next = QTD_NEXT (dma);
880 /* let the hc process these next qtds */
882 dummy->hw_token = token;
884 urb->hcpriv = qh_get (qh);
890 /*-------------------------------------------------------------------------*/
894 struct ehci_hcd *ehci,
896 struct list_head *qtd_list,
899 struct ehci_qtd *qtd;
903 struct ehci_qh *qh = NULL;
905 qtd = list_entry (qtd_list->next, struct ehci_qtd, qtd_list);
906 dev = (struct hcd_dev *)urb->dev->hcpriv;
907 epnum = usb_pipeendpoint (urb->pipe);
908 if (usb_pipein (urb->pipe) && !usb_pipecontrol (urb->pipe))
911 #ifdef EHCI_URB_TRACE
913 "%s %s urb %p ep%d%s len %d, qtd %p [qh %p]\n",
914 __FUNCTION__, urb->dev->devpath, urb,
915 epnum & 0x0f, usb_pipein (urb->pipe) ? "in" : "out",
916 urb->transfer_buffer_length,
917 qtd, dev ? dev->ep [epnum] : (void *)~0);
920 spin_lock_irqsave (&ehci->lock, flags);
921 qh = qh_append_tds (ehci, urb, qtd_list, epnum, &dev->ep [epnum]);
923 /* Control/bulk operations through TTs don't need scheduling,
924 * the HC and TT handle it when the TT has a buffer ready.
926 if (likely (qh != 0)) {
927 if (likely (qh->qh_state == QH_STATE_IDLE))
928 qh_link_async (ehci, qh_get (qh));
930 spin_unlock_irqrestore (&ehci->lock, flags);
931 if (unlikely (qh == 0)) {
932 qtd_list_free (ehci, urb, qtd_list);
938 /*-------------------------------------------------------------------------*/
940 /* the async qh for the qtds being reclaimed are now unlinked from the HC */
942 static void start_unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh);
944 static void end_unlink_async (struct ehci_hcd *ehci, struct pt_regs *regs)
946 struct ehci_qh *qh = ehci->reclaim;
947 struct ehci_qh *next;
949 timer_action_done (ehci, TIMER_IAA_WATCHDOG);
951 // qh->hw_next = cpu_to_le32 (qh->qh_dma);
952 qh->qh_state = QH_STATE_IDLE;
953 qh->qh_next.qh = NULL;
954 qh_put (qh); // refcount from reclaim
956 /* other unlink(s) may be pending (in QH_STATE_UNLINK_WAIT) */
958 ehci->reclaim = next;
959 ehci->reclaim_ready = 0;
962 qh_completions (ehci, qh, regs);
964 if (!list_empty (&qh->qtd_list)
965 && HCD_IS_RUNNING (ehci->hcd.state))
966 qh_link_async (ehci, qh);
968 qh_put (qh); // refcount from async list
970 /* it's not free to turn the async schedule on/off; leave it
971 * active but idle for a while once it empties.
973 if (HCD_IS_RUNNING (ehci->hcd.state)
974 && ehci->async->qh_next.qh == 0)
975 timer_action (ehci, TIMER_ASYNC_OFF);
979 ehci->reclaim = NULL;
980 start_unlink_async (ehci, next);
984 /* makes sure the async qh will become idle */
985 /* caller must own ehci->lock */
987 static void start_unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh)
989 int cmd = readl (&ehci->regs->command);
990 struct ehci_qh *prev;
994 || (qh->qh_state != QH_STATE_LINKED
995 && qh->qh_state != QH_STATE_UNLINK_WAIT)
997 // this macro lies except on SMP compiles
998 || !spin_is_locked (&ehci->lock)
1004 /* stop async schedule right now? */
1005 if (unlikely (qh == ehci->async)) {
1006 /* can't get here without STS_ASS set */
1007 if (ehci->hcd.state != USB_STATE_HALT) {
1008 writel (cmd & ~CMD_ASE, &ehci->regs->command);
1010 // handshake later, if we need to
1012 timer_action_done (ehci, TIMER_ASYNC_OFF);
1016 qh->qh_state = QH_STATE_UNLINK;
1017 ehci->reclaim = qh = qh_get (qh);
1020 while (prev->qh_next.qh != qh)
1021 prev = prev->qh_next.qh;
1023 prev->hw_next = qh->hw_next;
1024 prev->qh_next = qh->qh_next;
1027 if (unlikely (ehci->hcd.state == USB_STATE_HALT)) {
1028 /* if (unlikely (qh->reclaim != 0))
1029 * this will recurse, probably not much
1031 end_unlink_async (ehci, NULL);
1035 ehci->reclaim_ready = 0;
1037 writel (cmd, &ehci->regs->command);
1038 (void) readl (&ehci->regs->command);
1039 timer_action (ehci, TIMER_IAA_WATCHDOG);
1042 /*-------------------------------------------------------------------------*/
1045 scan_async (struct ehci_hcd *ehci, struct pt_regs *regs)
1048 enum ehci_timer_action action = TIMER_IO_WATCHDOG;
1050 if (!++(ehci->stamp))
1052 timer_action_done (ehci, TIMER_ASYNC_SHRINK);
1054 qh = ehci->async->qh_next.qh;
1055 if (likely (qh != 0)) {
1057 /* clean any finished work for this qh */
1058 if (!list_empty (&qh->qtd_list)
1059 && qh->stamp != ehci->stamp) {
1062 /* unlinks could happen here; completion
1063 * reporting drops the lock. rescan using
1064 * the latest schedule, but don't rescan
1065 * qhs we already finished (no looping).
1068 qh->stamp = ehci->stamp;
1069 temp = qh_completions (ehci, qh, regs);
1076 /* unlink idle entries, reducing HC PCI usage as well
1077 * as HCD schedule-scanning costs. delay for any qh
1078 * we just scanned, there's a not-unusual case that it
1079 * doesn't stay idle for long.
1080 * (plus, avoids some kind of re-activation race.)
1082 if (list_empty (&qh->qtd_list)) {
1083 if (qh->stamp == ehci->stamp)
1084 action = TIMER_ASYNC_SHRINK;
1085 else if (!ehci->reclaim
1086 && qh->qh_state == QH_STATE_LINKED)
1087 start_unlink_async (ehci, qh);
1090 qh = qh->qh_next.qh;
1093 if (action == TIMER_ASYNC_SHRINK)
1094 timer_action (ehci, TIMER_ASYNC_SHRINK);