blob: 1976b1b3778cd3de2d7946733fbda37edb6a7108 [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
David Brownell53bd6a62006-08-30 14:50:06 -07003 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07004 * 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".
David Brownell53bd6a62006-08-30 14:50:06 -070034 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070035 * 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
Stefan Roese6dbd6822007-05-01 09:29:37 -070046qtd_fill(struct ehci_hcd *ehci, struct ehci_qtd *qtd, dma_addr_t buf,
47 size_t len, int token, int maxpacket)
Linus Torvalds1da177e2005-04-16 15:20:36 -070048{
49 int i, count;
50 u64 addr = buf;
51
52 /* one buffer entry per 4K ... first might be short or unaligned */
Stefan Roese6dbd6822007-05-01 09:29:37 -070053 qtd->hw_buf[0] = cpu_to_hc32(ehci, (u32)addr);
54 qtd->hw_buf_hi[0] = cpu_to_hc32(ehci, (u32)(addr >> 32));
Linus Torvalds1da177e2005-04-16 15:20:36 -070055 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;
Stefan Roese6dbd6822007-05-01 09:29:37 -070065 qtd->hw_buf[i] = cpu_to_hc32(ehci, (u32)addr);
66 qtd->hw_buf_hi[i] = cpu_to_hc32(ehci,
67 (u32)(addr >> 32));
Linus Torvalds1da177e2005-04-16 15:20:36 -070068 buf += 0x1000;
69 if ((count + 0x1000) < len)
70 count += 0x1000;
71 else
72 count = len;
73 }
74
75 /* short packets may only terminate transfers */
76 if (count != len)
77 count -= (count % maxpacket);
78 }
Stefan Roese6dbd6822007-05-01 09:29:37 -070079 qtd->hw_token = cpu_to_hc32(ehci, (count << 16) | token);
Linus Torvalds1da177e2005-04-16 15:20:36 -070080 qtd->length = count;
81
82 return count;
83}
84
85/*-------------------------------------------------------------------------*/
86
87static inline void
88qh_update (struct ehci_hcd *ehci, struct ehci_qh *qh, struct ehci_qtd *qtd)
89{
90 /* writes to an active overlay are unsafe */
91 BUG_ON(qh->qh_state != QH_STATE_IDLE);
92
Stefan Roese6dbd6822007-05-01 09:29:37 -070093 qh->hw_qtd_next = QTD_NEXT(ehci, qtd->qtd_dma);
94 qh->hw_alt_next = EHCI_LIST_END(ehci);
Linus Torvalds1da177e2005-04-16 15:20:36 -070095
96 /* Except for control endpoints, we make hardware maintain data
97 * toggle (like OHCI) ... here (re)initialize the toggle in the QH,
98 * and set the pseudo-toggle in udev. Only usb_clear_halt() will
99 * ever clear it.
100 */
Stefan Roese6dbd6822007-05-01 09:29:37 -0700101 if (!(qh->hw_info1 & cpu_to_hc32(ehci, 1 << 14))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102 unsigned is_out, epnum;
103
Stefan Roese6dbd6822007-05-01 09:29:37 -0700104 is_out = !(qtd->hw_token & cpu_to_hc32(ehci, 1 << 8));
105 epnum = (hc32_to_cpup(ehci, &qh->hw_info1) >> 8) & 0x0f;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106 if (unlikely (!usb_gettoggle (qh->dev, epnum, is_out))) {
Stefan Roese6dbd6822007-05-01 09:29:37 -0700107 qh->hw_token &= ~cpu_to_hc32(ehci, QTD_TOGGLE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 usb_settoggle (qh->dev, epnum, is_out, 1);
109 }
110 }
111
112 /* HC must see latest qtd and qh data before we clear ACTIVE+HALT */
113 wmb ();
Stefan Roese6dbd6822007-05-01 09:29:37 -0700114 qh->hw_token &= cpu_to_hc32(ehci, QTD_TOGGLE | QTD_STS_PING);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115}
116
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...
120 */
121static void
122qh_refresh (struct ehci_hcd *ehci, struct ehci_qh *qh)
123{
124 struct ehci_qtd *qtd;
125
126 if (list_empty (&qh->qtd_list))
127 qtd = qh->dummy;
128 else {
129 qtd = list_entry (qh->qtd_list.next,
130 struct ehci_qtd, qtd_list);
131 /* first qtd may already be partially processed */
Stefan Roese6dbd6822007-05-01 09:29:37 -0700132 if (cpu_to_hc32(ehci, qtd->qtd_dma) == qh->hw_current)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133 qtd = NULL;
134 }
135
136 if (qtd)
137 qh_update (ehci, qh, qtd);
138}
139
140/*-------------------------------------------------------------------------*/
141
Alan Stern14c04c02007-08-24 15:40:19 -0400142static int qtd_copy_status (
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143 struct ehci_hcd *ehci,
144 struct urb *urb,
145 size_t length,
146 u32 token
147)
148{
Alan Stern14c04c02007-08-24 15:40:19 -0400149 int status = -EINPROGRESS;
150
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151 /* count IN/OUT bytes, not SETUP (even short packets) */
152 if (likely (QTD_PID (token) != 2))
153 urb->actual_length += length - QTD_LENGTH (token);
154
155 /* don't modify error codes */
Alan Sterneb231052007-08-21 15:40:36 -0400156 if (unlikely(urb->unlinked))
Alan Stern14c04c02007-08-24 15:40:19 -0400157 return status;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158
159 /* force cleanup after short read; not always an error */
160 if (unlikely (IS_SHORT_READ (token)))
Alan Stern14c04c02007-08-24 15:40:19 -0400161 status = -EREMOTEIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162
163 /* serious "can't proceed" faults reported by the hardware */
164 if (token & QTD_STS_HALT) {
165 if (token & QTD_STS_BABBLE) {
166 /* FIXME "must" disable babbling device's port too */
Alan Stern14c04c02007-08-24 15:40:19 -0400167 status = -EOVERFLOW;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168 } else if (token & QTD_STS_MMF) {
169 /* fs/ls interrupt xfer missed the complete-split */
Alan Stern14c04c02007-08-24 15:40:19 -0400170 status = -EPROTO;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700171 } else if (token & QTD_STS_DBE) {
Alan Stern14c04c02007-08-24 15:40:19 -0400172 status = (QTD_PID (token) == 1) /* IN ? */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173 ? -ENOSR /* hc couldn't read data */
174 : -ECOMM; /* hc couldn't write data */
175 } else if (token & QTD_STS_XACT) {
176 /* timeout, bad crc, wrong PID, etc; retried */
177 if (QTD_CERR (token))
Alan Stern14c04c02007-08-24 15:40:19 -0400178 status = -EPIPE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179 else {
180 ehci_dbg (ehci, "devpath %s ep%d%s 3strikes\n",
181 urb->dev->devpath,
182 usb_pipeendpoint (urb->pipe),
183 usb_pipein (urb->pipe) ? "in" : "out");
Alan Stern14c04c02007-08-24 15:40:19 -0400184 status = -EPROTO;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 }
186 /* CERR nonzero + no errors + halt --> stall */
187 } else if (QTD_CERR (token))
Alan Stern14c04c02007-08-24 15:40:19 -0400188 status = -EPIPE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189 else /* unknown */
Alan Stern14c04c02007-08-24 15:40:19 -0400190 status = -EPROTO;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191
192 ehci_vdbg (ehci,
193 "dev%d ep%d%s qtd token %08x --> status %d\n",
194 usb_pipedevice (urb->pipe),
195 usb_pipeendpoint (urb->pipe),
196 usb_pipein (urb->pipe) ? "in" : "out",
Alan Stern14c04c02007-08-24 15:40:19 -0400197 token, status);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198
199 /* if async CSPLIT failed, try cleaning out the TT buffer */
Alan Stern14c04c02007-08-24 15:40:19 -0400200 if (status != -EPIPE
David Brownell340ba5f2007-12-19 11:30:39 -0800201 && urb->dev->tt
202 && !usb_pipeint(urb->pipe)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203 && ((token & QTD_STS_MMF) != 0
204 || QTD_CERR(token) == 0)
205 && (!ehci_is_TDI(ehci)
David Brownell53bd6a62006-08-30 14:50:06 -0700206 || urb->dev->tt->hub !=
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207 ehci_to_hcd(ehci)->self.root_hub)) {
208#ifdef DEBUG
209 struct usb_device *tt = urb->dev->tt->hub;
210 dev_dbg (&tt->dev,
211 "clear tt buffer port %d, a%d ep%d t%08x\n",
212 urb->dev->ttport, urb->dev->devnum,
213 usb_pipeendpoint (urb->pipe), token);
214#endif /* DEBUG */
David Brownell340ba5f2007-12-19 11:30:39 -0800215 /* REVISIT ARC-derived cores don't clear the root
216 * hub TT buffer in this way...
217 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218 usb_hub_tt_clear_buffer (urb->dev, urb->pipe);
219 }
220 }
Alan Stern14c04c02007-08-24 15:40:19 -0400221
222 return status;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223}
224
225static void
Alan Stern14c04c02007-08-24 15:40:19 -0400226ehci_urb_done(struct ehci_hcd *ehci, struct urb *urb, int status)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227__releases(ehci->lock)
228__acquires(ehci->lock)
229{
230 if (likely (urb->hcpriv != NULL)) {
231 struct ehci_qh *qh = (struct ehci_qh *) urb->hcpriv;
232
233 /* S-mask in a QH means it's an interrupt urb */
Stefan Roese6dbd6822007-05-01 09:29:37 -0700234 if ((qh->hw_info2 & cpu_to_hc32(ehci, QH_SMASK)) != 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235
236 /* ... update hc-wide periodic stats (for usbfs) */
237 ehci_to_hcd(ehci)->self.bandwidth_int_reqs--;
238 }
239 qh_put (qh);
240 }
241
Alan Sterneb231052007-08-21 15:40:36 -0400242 if (unlikely(urb->unlinked)) {
243 COUNT(ehci->stats.unlink);
244 } else {
David Brownell4f667622008-04-12 08:32:05 -0700245 /* report non-error and short read status as zero */
246 if (status == -EINPROGRESS || status == -EREMOTEIO)
Alan Stern14c04c02007-08-24 15:40:19 -0400247 status = 0;
Alan Sterneb231052007-08-21 15:40:36 -0400248 COUNT(ehci->stats.complete);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250
251#ifdef EHCI_URB_TRACE
252 ehci_dbg (ehci,
253 "%s %s urb %p ep%d%s status %d len %d/%d\n",
Harvey Harrison441b62c2008-03-03 16:08:34 -0800254 __func__, urb->dev->devpath, urb,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255 usb_pipeendpoint (urb->pipe),
256 usb_pipein (urb->pipe) ? "in" : "out",
Alan Stern14c04c02007-08-24 15:40:19 -0400257 status,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 urb->actual_length, urb->transfer_buffer_length);
259#endif
260
261 /* complete() can reenter this HCD */
Alan Sterne9df41c2007-08-08 11:48:02 -0400262 usb_hcd_unlink_urb_from_ep(ehci_to_hcd(ehci), urb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263 spin_unlock (&ehci->lock);
Alan Stern4a000272007-08-24 15:42:24 -0400264 usb_hcd_giveback_urb(ehci_to_hcd(ehci), urb, status);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265 spin_lock (&ehci->lock);
266}
267
268static void start_unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh);
269static void unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh);
270
271static void intr_deschedule (struct ehci_hcd *ehci, struct ehci_qh *qh);
272static int qh_schedule (struct ehci_hcd *ehci, struct ehci_qh *qh);
273
274/*
275 * Process and free completed qtds for a qh, returning URBs to drivers.
276 * Chases up to qh->hw_current. Returns number of completions called,
277 * indicating how much "real" work we did.
278 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279static unsigned
David Howells7d12e782006-10-05 14:55:46 +0100280qh_completions (struct ehci_hcd *ehci, struct ehci_qh *qh)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281{
282 struct ehci_qtd *last = NULL, *end = qh->dummy;
283 struct list_head *entry, *tmp;
Alan Stern14c04c02007-08-24 15:40:19 -0400284 int last_status = -EINPROGRESS;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285 int stopped;
286 unsigned count = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 u8 state;
Al Virofd05e722008-04-28 07:00:16 +0100288 __le32 halt = HALT_BIT(ehci);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289
290 if (unlikely (list_empty (&qh->qtd_list)))
291 return count;
292
293 /* completions (or tasks on other cpus) must never clobber HALT
294 * till we've gone through and cleaned everything up, even when
295 * they add urbs to this qh's queue or mark them for unlinking.
296 *
297 * NOTE: unlinking expects to be done in queue order.
298 */
299 state = qh->qh_state;
300 qh->qh_state = QH_STATE_COMPLETING;
301 stopped = (state == QH_STATE_IDLE);
302
303 /* remove de-activated QTDs from front of queue.
304 * after faults (including short reads), cleanup this urb
305 * then let the queue advance.
306 * if queue is stopped, handles unlinks.
307 */
308 list_for_each_safe (entry, tmp, &qh->qtd_list) {
309 struct ehci_qtd *qtd;
310 struct urb *urb;
311 u32 token = 0;
312
313 qtd = list_entry (entry, struct ehci_qtd, qtd_list);
314 urb = qtd->urb;
315
316 /* clean up any state from previous QTD ...*/
317 if (last) {
318 if (likely (last->urb != urb)) {
Alan Stern14c04c02007-08-24 15:40:19 -0400319 ehci_urb_done(ehci, last->urb, last_status);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320 count++;
Misha Zhilinb5f7a0e2008-02-27 18:05:24 -0800321 last_status = -EINPROGRESS;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322 }
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 ();
Stefan Roese6dbd6822007-05-01 09:29:37 -0700333 token = hc32_to_cpu(ehci, qtd->hw_token);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334
335 /* always clean up qtds the hc de-activated */
Alan Sterna2c27062009-02-10 10:16:58 -0500336 retry_xacterr:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337 if ((token & QTD_STS_ACTIVE) == 0) {
338
David Brownella082b5c2008-04-10 14:21:06 -0700339 /* on STALL, error, and short reads this urb must
340 * complete and all its qtds must be recycled.
341 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342 if ((token & QTD_STS_HALT) != 0) {
Alan Sterna2c27062009-02-10 10:16:58 -0500343
344 /* retry transaction errors until we
345 * reach the software xacterr limit
346 */
347 if ((token & QTD_STS_XACT) &&
348 QTD_CERR(token) == 0 &&
349 --qh->xacterrs > 0 &&
350 !urb->unlinked) {
351 ehci_dbg(ehci,
Randy Dunlapd0626802009-02-13 11:22:06 -0800352 "detected XactErr len %zu/%zu retry %d\n",
Alan Sterna2c27062009-02-10 10:16:58 -0500353 qtd->length - QTD_LENGTH(token), qtd->length,
354 QH_XACTERR_MAX - qh->xacterrs);
355
356 /* reset the token in the qtd and the
357 * qh overlay (which still contains
358 * the qtd) so that we pick up from
359 * where we left off
360 */
361 token &= ~QTD_STS_HALT;
362 token |= QTD_STS_ACTIVE |
363 (EHCI_TUNE_CERR << 10);
364 qtd->hw_token = cpu_to_hc32(ehci,
365 token);
366 wmb();
367 qh->hw_token = cpu_to_hc32(ehci, token);
368 goto retry_xacterr;
369 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370 stopped = 1;
371
372 /* magic dummy for some short reads; qh won't advance.
373 * that silicon quirk can kick in with this dummy too.
David Brownella082b5c2008-04-10 14:21:06 -0700374 *
375 * other short reads won't stop the queue, including
376 * control transfers (status stage handles that) or
377 * most other single-qtd reads ... the queue stops if
378 * URB_SHORT_NOT_OK was set so the driver submitting
379 * the urbs could clean it up.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380 */
381 } else if (IS_SHORT_READ (token)
Stefan Roese6dbd6822007-05-01 09:29:37 -0700382 && !(qtd->hw_alt_next
383 & EHCI_LIST_END(ehci))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384 stopped = 1;
385 goto halt;
386 }
387
388 /* stop scanning when we reach qtds the hc is using */
389 } else if (likely (!stopped
390 && HC_IS_RUNNING (ehci_to_hcd(ehci)->state))) {
391 break;
392
David Brownella082b5c2008-04-10 14:21:06 -0700393 /* scan the whole queue for unlinks whenever it stops */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394 } else {
395 stopped = 1;
396
David Brownella082b5c2008-04-10 14:21:06 -0700397 /* cancel everything if we halt, suspend, etc */
398 if (!HC_IS_RUNNING(ehci_to_hcd(ehci)->state))
Alan Stern14c04c02007-08-24 15:40:19 -0400399 last_status = -ESHUTDOWN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400
David Brownella082b5c2008-04-10 14:21:06 -0700401 /* this qtd is active; skip it unless a previous qtd
402 * for its urb faulted, or its urb was canceled.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 */
David Brownella082b5c2008-04-10 14:21:06 -0700404 else if (last_status == -EINPROGRESS && !urb->unlinked)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405 continue;
David Brownell53bd6a62006-08-30 14:50:06 -0700406
David Brownella082b5c2008-04-10 14:21:06 -0700407 /* qh unlinked; token in overlay may be most current */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408 if (state == QH_STATE_IDLE
Stefan Roese6dbd6822007-05-01 09:29:37 -0700409 && cpu_to_hc32(ehci, qtd->qtd_dma)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410 == qh->hw_current)
Stefan Roese6dbd6822007-05-01 09:29:37 -0700411 token = hc32_to_cpu(ehci, qh->hw_token);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412
413 /* force halt for unlinked or blocked qh, so we'll
414 * patch the qh later and so that completions can't
415 * activate it while we "know" it's stopped.
416 */
Stefan Roese6dbd6822007-05-01 09:29:37 -0700417 if ((halt & qh->hw_token) == 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700418halt:
Stefan Roese6dbd6822007-05-01 09:29:37 -0700419 qh->hw_token |= halt;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700420 wmb ();
421 }
422 }
David Brownell53bd6a62006-08-30 14:50:06 -0700423
David Brownell4f667622008-04-12 08:32:05 -0700424 /* unless we already know the urb's status, collect qtd status
425 * and update count of bytes transferred. in common short read
426 * cases with only one data qtd (including control transfers),
427 * queue processing won't halt. but with two or more qtds (for
428 * example, with a 32 KB transfer), when the first qtd gets a
429 * short read the second must be removed by hand.
430 */
431 if (last_status == -EINPROGRESS) {
432 last_status = qtd_copy_status(ehci, urb,
433 qtd->length, token);
434 if (last_status == -EREMOTEIO
435 && (qtd->hw_alt_next
436 & EHCI_LIST_END(ehci)))
437 last_status = -EINPROGRESS;
Alan Sternb0d9efb2007-08-21 15:39:21 -0400438 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439
David Brownella082b5c2008-04-10 14:21:06 -0700440 /* if we're removing something not at the queue head,
441 * patch the hardware queue pointer.
442 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443 if (stopped && qtd->qtd_list.prev != &qh->qtd_list) {
444 last = list_entry (qtd->qtd_list.prev,
445 struct ehci_qtd, qtd_list);
446 last->hw_next = qtd->hw_next;
447 }
David Brownella082b5c2008-04-10 14:21:06 -0700448
449 /* remove qtd; it's recycled after possible urb completion */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450 list_del (&qtd->qtd_list);
451 last = qtd;
Alan Sterna2c27062009-02-10 10:16:58 -0500452
453 /* reinit the xacterr counter for the next qtd */
454 qh->xacterrs = QH_XACTERR_MAX;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455 }
456
457 /* last urb's completion might still need calling */
458 if (likely (last != NULL)) {
Alan Stern14c04c02007-08-24 15:40:19 -0400459 ehci_urb_done(ehci, last->urb, last_status);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460 count++;
461 ehci_qtd_free (ehci, last);
462 }
463
464 /* restore original state; caller must unlink or relink */
465 qh->qh_state = state;
466
467 /* be sure the hardware's done with the qh before refreshing
468 * it after fault cleanup, or recovering from silicon wrongly
469 * overlaying the dummy qtd (which reduces DMA chatter).
470 */
Stefan Roese6dbd6822007-05-01 09:29:37 -0700471 if (stopped != 0 || qh->hw_qtd_next == EHCI_LIST_END(ehci)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472 switch (state) {
473 case QH_STATE_IDLE:
474 qh_refresh(ehci, qh);
475 break;
476 case QH_STATE_LINKED:
David Brownella082b5c2008-04-10 14:21:06 -0700477 /* We won't refresh a QH that's linked (after the HC
478 * stopped the queue). That avoids a race:
479 * - HC reads first part of QH;
480 * - CPU updates that first part and the token;
481 * - HC reads rest of that QH, including token
482 * Result: HC gets an inconsistent image, and then
483 * DMAs to/from the wrong memory (corrupting it).
484 *
485 * That should be rare for interrupt transfers,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486 * except maybe high bandwidth ...
487 */
Stefan Roese6dbd6822007-05-01 09:29:37 -0700488 if ((cpu_to_hc32(ehci, QH_SMASK)
David Brownell7dedacf2005-08-04 18:06:41 -0700489 & qh->hw_info2) != 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700490 intr_deschedule (ehci, qh);
491 (void) qh_schedule (ehci, qh);
492 } else
493 unlink_async (ehci, qh);
494 break;
495 /* otherwise, unlink already started */
496 }
497 }
498
499 return count;
500}
501
502/*-------------------------------------------------------------------------*/
503
504// high bandwidth multiplier, as encoded in highspeed endpoint descriptors
505#define hb_mult(wMaxPacketSize) (1 + (((wMaxPacketSize) >> 11) & 0x03))
506// ... and packet size, for any kind of endpoint descriptor
507#define max_packet(wMaxPacketSize) ((wMaxPacketSize) & 0x07ff)
508
509/*
510 * reverse of qh_urb_transaction: free a list of TDs.
511 * used for cleanup after errors, before HC sees an URB's TDs.
512 */
513static void qtd_list_free (
514 struct ehci_hcd *ehci,
515 struct urb *urb,
516 struct list_head *qtd_list
517) {
518 struct list_head *entry, *temp;
519
520 list_for_each_safe (entry, temp, qtd_list) {
521 struct ehci_qtd *qtd;
522
523 qtd = list_entry (entry, struct ehci_qtd, qtd_list);
524 list_del (&qtd->qtd_list);
525 ehci_qtd_free (ehci, qtd);
526 }
527}
528
529/*
530 * create a list of filled qtds for this URB; won't link into qh.
531 */
532static struct list_head *
533qh_urb_transaction (
534 struct ehci_hcd *ehci,
535 struct urb *urb,
536 struct list_head *head,
Al Viro55016f12005-10-21 03:21:58 -0400537 gfp_t flags
Linus Torvalds1da177e2005-04-16 15:20:36 -0700538) {
539 struct ehci_qtd *qtd, *qtd_prev;
540 dma_addr_t buf;
541 int len, maxpacket;
542 int is_input;
543 u32 token;
544
545 /*
546 * URBs map to sequences of QTDs: one logical transaction
547 */
548 qtd = ehci_qtd_alloc (ehci, flags);
549 if (unlikely (!qtd))
550 return NULL;
551 list_add_tail (&qtd->qtd_list, head);
552 qtd->urb = urb;
553
554 token = QTD_STS_ACTIVE;
555 token |= (EHCI_TUNE_CERR << 10);
556 /* for split transactions, SplitXState initialized to zero */
557
558 len = urb->transfer_buffer_length;
559 is_input = usb_pipein (urb->pipe);
560 if (usb_pipecontrol (urb->pipe)) {
561 /* SETUP pid */
Stefan Roese6dbd6822007-05-01 09:29:37 -0700562 qtd_fill(ehci, qtd, urb->setup_dma,
563 sizeof (struct usb_ctrlrequest),
564 token | (2 /* "setup" */ << 8), 8);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565
566 /* ... and always at least one more pid */
567 token ^= QTD_TOGGLE;
568 qtd_prev = qtd;
569 qtd = ehci_qtd_alloc (ehci, flags);
570 if (unlikely (!qtd))
571 goto cleanup;
572 qtd->urb = urb;
Stefan Roese6dbd6822007-05-01 09:29:37 -0700573 qtd_prev->hw_next = QTD_NEXT(ehci, qtd->qtd_dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574 list_add_tail (&qtd->qtd_list, head);
Alan Stern69123542005-11-03 11:44:49 -0500575
576 /* for zero length DATA stages, STATUS is always IN */
577 if (len == 0)
578 token |= (1 /* "in" */ << 8);
David Brownell53bd6a62006-08-30 14:50:06 -0700579 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700580
581 /*
582 * data transfer stage: buffer setup
583 */
Alan Stern69123542005-11-03 11:44:49 -0500584 buf = urb->transfer_dma;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585
Alan Stern69123542005-11-03 11:44:49 -0500586 if (is_input)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700587 token |= (1 /* "in" */ << 8);
588 /* else it's already initted to "out" pid (0 << 8) */
589
590 maxpacket = max_packet(usb_maxpacket(urb->dev, urb->pipe, !is_input));
591
592 /*
593 * buffer gets wrapped in one or more qtds;
594 * last one may be "short" (including zero len)
595 * and may serve as a control status ack
596 */
597 for (;;) {
598 int this_qtd_len;
599
Stefan Roese6dbd6822007-05-01 09:29:37 -0700600 this_qtd_len = qtd_fill(ehci, qtd, buf, len, token, maxpacket);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601 len -= this_qtd_len;
602 buf += this_qtd_len;
David Brownella082b5c2008-04-10 14:21:06 -0700603
604 /*
605 * short reads advance to a "magic" dummy instead of the next
606 * qtd ... that forces the queue to stop, for manual cleanup.
607 * (this will usually be overridden later.)
608 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609 if (is_input)
610 qtd->hw_alt_next = ehci->async->hw_alt_next;
611
612 /* qh makes control packets use qtd toggle; maybe switch it */
613 if ((maxpacket & (this_qtd_len + (maxpacket - 1))) == 0)
614 token ^= QTD_TOGGLE;
615
616 if (likely (len <= 0))
617 break;
618
619 qtd_prev = qtd;
620 qtd = ehci_qtd_alloc (ehci, flags);
621 if (unlikely (!qtd))
622 goto cleanup;
623 qtd->urb = urb;
Stefan Roese6dbd6822007-05-01 09:29:37 -0700624 qtd_prev->hw_next = QTD_NEXT(ehci, qtd->qtd_dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 list_add_tail (&qtd->qtd_list, head);
626 }
627
David Brownella082b5c2008-04-10 14:21:06 -0700628 /*
629 * unless the caller requires manual cleanup after short reads,
630 * have the alt_next mechanism keep the queue running after the
631 * last data qtd (the only one, for control and most other cases).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700632 */
633 if (likely ((urb->transfer_flags & URB_SHORT_NOT_OK) == 0
634 || usb_pipecontrol (urb->pipe)))
Stefan Roese6dbd6822007-05-01 09:29:37 -0700635 qtd->hw_alt_next = EHCI_LIST_END(ehci);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636
637 /*
638 * control requests may need a terminating data "status" ack;
639 * bulk ones may need a terminating short packet (zero length).
640 */
Alan Stern69123542005-11-03 11:44:49 -0500641 if (likely (urb->transfer_buffer_length != 0)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642 int one_more = 0;
643
644 if (usb_pipecontrol (urb->pipe)) {
645 one_more = 1;
646 token ^= 0x0100; /* "in" <--> "out" */
647 token |= QTD_TOGGLE; /* force DATA1 */
648 } else if (usb_pipebulk (urb->pipe)
649 && (urb->transfer_flags & URB_ZERO_PACKET)
650 && !(urb->transfer_buffer_length % maxpacket)) {
651 one_more = 1;
652 }
653 if (one_more) {
654 qtd_prev = qtd;
655 qtd = ehci_qtd_alloc (ehci, flags);
656 if (unlikely (!qtd))
657 goto cleanup;
658 qtd->urb = urb;
Stefan Roese6dbd6822007-05-01 09:29:37 -0700659 qtd_prev->hw_next = QTD_NEXT(ehci, qtd->qtd_dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660 list_add_tail (&qtd->qtd_list, head);
661
662 /* never any data in such packets */
Stefan Roese6dbd6822007-05-01 09:29:37 -0700663 qtd_fill(ehci, qtd, 0, 0, token, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700664 }
665 }
666
667 /* by default, enable interrupt on urb completion */
668 if (likely (!(urb->transfer_flags & URB_NO_INTERRUPT)))
Stefan Roese6dbd6822007-05-01 09:29:37 -0700669 qtd->hw_token |= cpu_to_hc32(ehci, QTD_IOC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700670 return head;
671
672cleanup:
673 qtd_list_free (ehci, urb, head);
674 return NULL;
675}
676
677/*-------------------------------------------------------------------------*/
678
679// Would be best to create all qh's from config descriptors,
680// when each interface/altsetting is established. Unlink
681// any previous qh and cancel its urbs first; endpoints are
682// implicitly reset then (data toggle too).
683// That'd mean updating how usbcore talks to HCDs. (2.7?)
684
685
686/*
687 * Each QH holds a qtd list; a QH is used for everything except iso.
688 *
689 * For interrupt urbs, the scheduler must set the microframe scheduling
690 * mask(s) each time the QH gets scheduled. For highspeed, that's
691 * just one microframe in the s-mask. For split interrupt transactions
692 * there are additional complications: c-mask, maybe FSTNs.
693 */
694static struct ehci_qh *
695qh_make (
696 struct ehci_hcd *ehci,
697 struct urb *urb,
Al Viro55016f12005-10-21 03:21:58 -0400698 gfp_t flags
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699) {
700 struct ehci_qh *qh = ehci_qh_alloc (ehci, flags);
701 u32 info1 = 0, info2 = 0;
702 int is_input, type;
703 int maxp = 0;
David Brownell340ba5f2007-12-19 11:30:39 -0800704 struct usb_tt *tt = urb->dev->tt;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705
706 if (!qh)
707 return qh;
708
709 /*
710 * init endpoint/device data for this QH
711 */
712 info1 |= usb_pipeendpoint (urb->pipe) << 8;
713 info1 |= usb_pipedevice (urb->pipe) << 0;
714
715 is_input = usb_pipein (urb->pipe);
716 type = usb_pipetype (urb->pipe);
717 maxp = usb_maxpacket (urb->dev, urb->pipe, !is_input);
718
David Brownellcaa9ef62008-02-08 15:08:44 -0800719 /* 1024 byte maxpacket is a hardware ceiling. High bandwidth
720 * acts like up to 3KB, but is built from smaller packets.
721 */
722 if (max_packet(maxp) > 1024) {
723 ehci_dbg(ehci, "bogus qh maxpacket %d\n", max_packet(maxp));
724 goto done;
725 }
726
Linus Torvalds1da177e2005-04-16 15:20:36 -0700727 /* Compute interrupt scheduling parameters just once, and save.
728 * - allowing for high bandwidth, how many nsec/uframe are used?
729 * - split transactions need a second CSPLIT uframe; same question
730 * - splits also need a schedule gap (for full/low speed I/O)
731 * - qh has a polling interval
732 *
733 * For control/bulk requests, the HC or TT handles these.
734 */
735 if (type == PIPE_INTERRUPT) {
David Brownell340ba5f2007-12-19 11:30:39 -0800736 qh->usecs = NS_TO_US(usb_calc_bus_time(USB_SPEED_HIGH,
737 is_input, 0,
738 hb_mult(maxp) * max_packet(maxp)));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700739 qh->start = NO_FRAME;
740
741 if (urb->dev->speed == USB_SPEED_HIGH) {
742 qh->c_usecs = 0;
743 qh->gap_uf = 0;
744
745 qh->period = urb->interval >> 3;
746 if (qh->period == 0 && urb->interval != 1) {
747 /* NOTE interval 2 or 4 uframes could work.
748 * But interval 1 scheduling is simpler, and
749 * includes high bandwidth.
750 */
751 dbg ("intr period %d uframes, NYET!",
752 urb->interval);
753 goto done;
754 }
755 } else {
david-b@pacbell.netd0384202005-08-13 18:44:58 -0700756 int think_time;
757
Linus Torvalds1da177e2005-04-16 15:20:36 -0700758 /* gap is f(FS/LS transfer times) */
759 qh->gap_uf = 1 + usb_calc_bus_time (urb->dev->speed,
760 is_input, 0, maxp) / (125 * 1000);
761
762 /* FIXME this just approximates SPLIT/CSPLIT times */
763 if (is_input) { // SPLIT, gap, CSPLIT+DATA
764 qh->c_usecs = qh->usecs + HS_USECS (0);
765 qh->usecs = HS_USECS (1);
766 } else { // SPLIT+DATA, gap, CSPLIT
767 qh->usecs += HS_USECS (1);
768 qh->c_usecs = HS_USECS (0);
769 }
770
david-b@pacbell.netd0384202005-08-13 18:44:58 -0700771 think_time = tt ? tt->think_time : 0;
772 qh->tt_usecs = NS_TO_US (think_time +
773 usb_calc_bus_time (urb->dev->speed,
774 is_input, 0, max_packet (maxp)));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700775 qh->period = urb->interval;
776 }
777 }
778
779 /* support for tt scheduling, and access to toggles */
Alan Stern6a8e87b2006-01-19 10:46:27 -0500780 qh->dev = urb->dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781
782 /* using TT? */
783 switch (urb->dev->speed) {
784 case USB_SPEED_LOW:
785 info1 |= (1 << 12); /* EPS "low" */
786 /* FALL THROUGH */
787
788 case USB_SPEED_FULL:
789 /* EPS 0 means "full" */
790 if (type != PIPE_INTERRUPT)
791 info1 |= (EHCI_TUNE_RL_TT << 28);
792 if (type == PIPE_CONTROL) {
793 info1 |= (1 << 27); /* for TT */
794 info1 |= 1 << 14; /* toggle from qtd */
795 }
796 info1 |= maxp << 16;
797
798 info2 |= (EHCI_TUNE_MULT_TT << 30);
Kumar Gala8cd42e92006-01-20 13:57:52 -0800799
800 /* Some Freescale processors have an erratum in which the
801 * port number in the queue head was 0..N-1 instead of 1..N.
802 */
803 if (ehci_has_fsl_portno_bug(ehci))
804 info2 |= (urb->dev->ttport-1) << 23;
805 else
806 info2 |= urb->dev->ttport << 23;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700807
808 /* set the address of the TT; for TDI's integrated
809 * root hub tt, leave it zeroed.
810 */
David Brownell340ba5f2007-12-19 11:30:39 -0800811 if (tt && tt->hub != ehci_to_hcd(ehci)->self.root_hub)
812 info2 |= tt->hub->devnum << 16;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700813
814 /* NOTE: if (PIPE_INTERRUPT) { scheduler sets c-mask } */
815
816 break;
817
818 case USB_SPEED_HIGH: /* no TT involved */
819 info1 |= (2 << 12); /* EPS "high" */
820 if (type == PIPE_CONTROL) {
821 info1 |= (EHCI_TUNE_RL_HS << 28);
822 info1 |= 64 << 16; /* usb2 fixed maxpacket */
823 info1 |= 1 << 14; /* toggle from qtd */
824 info2 |= (EHCI_TUNE_MULT_HS << 30);
825 } else if (type == PIPE_BULK) {
826 info1 |= (EHCI_TUNE_RL_HS << 28);
David Brownellcaa9ef62008-02-08 15:08:44 -0800827 /* The USB spec says that high speed bulk endpoints
828 * always use 512 byte maxpacket. But some device
829 * vendors decided to ignore that, and MSFT is happy
830 * to help them do so. So now people expect to use
831 * such nonconformant devices with Linux too; sigh.
832 */
833 info1 |= max_packet(maxp) << 16;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700834 info2 |= (EHCI_TUNE_MULT_HS << 30);
835 } else { /* PIPE_INTERRUPT */
836 info1 |= max_packet (maxp) << 16;
837 info2 |= hb_mult (maxp) << 30;
838 }
839 break;
840 default:
David Brownell53bd6a62006-08-30 14:50:06 -0700841 dbg ("bogus dev %p speed %d", urb->dev, urb->dev->speed);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700842done:
843 qh_put (qh);
844 return NULL;
845 }
846
847 /* NOTE: if (PIPE_INTERRUPT) { scheduler sets s-mask } */
848
849 /* init as live, toggle clear, advance to dummy */
850 qh->qh_state = QH_STATE_IDLE;
Stefan Roese6dbd6822007-05-01 09:29:37 -0700851 qh->hw_info1 = cpu_to_hc32(ehci, info1);
852 qh->hw_info2 = cpu_to_hc32(ehci, info2);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700853 usb_settoggle (urb->dev, usb_pipeendpoint (urb->pipe), !is_input, 1);
854 qh_refresh (ehci, qh);
855 return qh;
856}
857
858/*-------------------------------------------------------------------------*/
859
860/* move qh (and its qtds) onto async queue; maybe enable queue. */
861
862static void qh_link_async (struct ehci_hcd *ehci, struct ehci_qh *qh)
863{
Stefan Roese6dbd6822007-05-01 09:29:37 -0700864 __hc32 dma = QH_NEXT(ehci, qh->qh_dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700865 struct ehci_qh *head;
866
867 /* (re)start the async schedule? */
868 head = ehci->async;
869 timer_action_done (ehci, TIMER_ASYNC_OFF);
870 if (!head->qh_next.qh) {
Benjamin Herrenschmidt083522d2006-12-15 06:54:08 +1100871 u32 cmd = ehci_readl(ehci, &ehci->regs->command);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700872
873 if (!(cmd & CMD_ASE)) {
874 /* in case a clear of CMD_ASE didn't take yet */
Benjamin Herrenschmidt083522d2006-12-15 06:54:08 +1100875 (void)handshake(ehci, &ehci->regs->status,
876 STS_ASS, 0, 150);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700877 cmd |= CMD_ASE | CMD_RUN;
Benjamin Herrenschmidt083522d2006-12-15 06:54:08 +1100878 ehci_writel(ehci, cmd, &ehci->regs->command);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879 ehci_to_hcd(ehci)->state = HC_STATE_RUNNING;
880 /* posted write need not be known to HC yet ... */
881 }
882 }
883
884 /* clear halt and/or toggle; and maybe recover from silicon quirk */
885 if (qh->qh_state == QH_STATE_IDLE)
886 qh_refresh (ehci, qh);
887
888 /* splice right after start */
889 qh->qh_next = head->qh_next;
890 qh->hw_next = head->hw_next;
891 wmb ();
892
893 head->qh_next.qh = qh;
894 head->hw_next = dma;
895
Alan Sterna2c27062009-02-10 10:16:58 -0500896 qh->xacterrs = QH_XACTERR_MAX;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700897 qh->qh_state = QH_STATE_LINKED;
898 /* qtd completions reported later by interrupt */
899}
900
901/*-------------------------------------------------------------------------*/
902
Linus Torvalds1da177e2005-04-16 15:20:36 -0700903/*
904 * For control/bulk/interrupt, return QH with these TDs appended.
905 * Allocates and initializes the QH if necessary.
906 * Returns null if it can't allocate a QH it needs to.
907 * If the QH has TDs (urbs) already, that's great.
908 */
909static struct ehci_qh *qh_append_tds (
910 struct ehci_hcd *ehci,
911 struct urb *urb,
912 struct list_head *qtd_list,
913 int epnum,
914 void **ptr
915)
916{
917 struct ehci_qh *qh = NULL;
Al Virofd05e722008-04-28 07:00:16 +0100918 __hc32 qh_addr_mask = cpu_to_hc32(ehci, 0x7f);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700919
920 qh = (struct ehci_qh *) *ptr;
921 if (unlikely (qh == NULL)) {
922 /* can't sleep here, we have ehci->lock... */
923 qh = qh_make (ehci, urb, GFP_ATOMIC);
924 *ptr = qh;
925 }
926 if (likely (qh != NULL)) {
927 struct ehci_qtd *qtd;
928
929 if (unlikely (list_empty (qtd_list)))
930 qtd = NULL;
931 else
932 qtd = list_entry (qtd_list->next, struct ehci_qtd,
933 qtd_list);
934
935 /* control qh may need patching ... */
936 if (unlikely (epnum == 0)) {
937
938 /* usb_reset_device() briefly reverts to address 0 */
939 if (usb_pipedevice (urb->pipe) == 0)
Stefan Roese6dbd6822007-05-01 09:29:37 -0700940 qh->hw_info1 &= ~qh_addr_mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700941 }
942
943 /* just one way to queue requests: swap with the dummy qtd.
944 * only hc or qh_refresh() ever modify the overlay.
945 */
946 if (likely (qtd != NULL)) {
947 struct ehci_qtd *dummy;
948 dma_addr_t dma;
Stefan Roese6dbd6822007-05-01 09:29:37 -0700949 __hc32 token;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700950
951 /* to avoid racing the HC, use the dummy td instead of
952 * the first td of our list (becomes new dummy). both
953 * tds stay deactivated until we're done, when the
954 * HC is allowed to fetch the old dummy (4.10.2).
955 */
956 token = qtd->hw_token;
Stefan Roese6dbd6822007-05-01 09:29:37 -0700957 qtd->hw_token = HALT_BIT(ehci);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700958 wmb ();
959 dummy = qh->dummy;
960
961 dma = dummy->qtd_dma;
962 *dummy = *qtd;
963 dummy->qtd_dma = dma;
964
965 list_del (&qtd->qtd_list);
966 list_add (&dummy->qtd_list, qtd_list);
Luis R. Rodriguez7d283ae2008-08-06 15:21:26 -0700967 list_splice_tail(qtd_list, &qh->qtd_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700968
Stefan Roese6dbd6822007-05-01 09:29:37 -0700969 ehci_qtd_init(ehci, qtd, qtd->qtd_dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700970 qh->dummy = qtd;
971
972 /* hc must see the new dummy at list end */
973 dma = qtd->qtd_dma;
974 qtd = list_entry (qh->qtd_list.prev,
975 struct ehci_qtd, qtd_list);
Stefan Roese6dbd6822007-05-01 09:29:37 -0700976 qtd->hw_next = QTD_NEXT(ehci, dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700977
978 /* let the hc process these next qtds */
979 wmb ();
980 dummy->hw_token = token;
981
982 urb->hcpriv = qh_get (qh);
983 }
984 }
985 return qh;
986}
987
988/*-------------------------------------------------------------------------*/
989
990static int
991submit_async (
992 struct ehci_hcd *ehci,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700993 struct urb *urb,
994 struct list_head *qtd_list,
Al Viro55016f12005-10-21 03:21:58 -0400995 gfp_t mem_flags
Linus Torvalds1da177e2005-04-16 15:20:36 -0700996) {
997 struct ehci_qtd *qtd;
998 int epnum;
999 unsigned long flags;
1000 struct ehci_qh *qh = NULL;
Alan Sterne9df41c2007-08-08 11:48:02 -04001001 int rc;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001002
1003 qtd = list_entry (qtd_list->next, struct ehci_qtd, qtd_list);
Alan Sterne9df41c2007-08-08 11:48:02 -04001004 epnum = urb->ep->desc.bEndpointAddress;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001005
1006#ifdef EHCI_URB_TRACE
1007 ehci_dbg (ehci,
1008 "%s %s urb %p ep%d%s len %d, qtd %p [qh %p]\n",
Harvey Harrison441b62c2008-03-03 16:08:34 -08001009 __func__, urb->dev->devpath, urb,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001010 epnum & 0x0f, (epnum & USB_DIR_IN) ? "in" : "out",
1011 urb->transfer_buffer_length,
Alan Sterne9df41c2007-08-08 11:48:02 -04001012 qtd, urb->ep->hcpriv);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001013#endif
1014
1015 spin_lock_irqsave (&ehci->lock, flags);
Benjamin Herrenschmidt8de98402005-11-25 09:59:46 +11001016 if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE,
1017 &ehci_to_hcd(ehci)->flags))) {
1018 rc = -ESHUTDOWN;
1019 goto done;
1020 }
Alan Sterne9df41c2007-08-08 11:48:02 -04001021 rc = usb_hcd_link_urb_to_ep(ehci_to_hcd(ehci), urb);
1022 if (unlikely(rc))
1023 goto done;
Benjamin Herrenschmidt8de98402005-11-25 09:59:46 +11001024
Alan Sterne9df41c2007-08-08 11:48:02 -04001025 qh = qh_append_tds(ehci, urb, qtd_list, epnum, &urb->ep->hcpriv);
Benjamin Herrenschmidt8de98402005-11-25 09:59:46 +11001026 if (unlikely(qh == NULL)) {
Alan Sterne9df41c2007-08-08 11:48:02 -04001027 usb_hcd_unlink_urb_from_ep(ehci_to_hcd(ehci), urb);
Benjamin Herrenschmidt8de98402005-11-25 09:59:46 +11001028 rc = -ENOMEM;
1029 goto done;
1030 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001031
1032 /* Control/bulk operations through TTs don't need scheduling,
1033 * the HC and TT handle it when the TT has a buffer ready.
1034 */
Benjamin Herrenschmidt8de98402005-11-25 09:59:46 +11001035 if (likely (qh->qh_state == QH_STATE_IDLE))
1036 qh_link_async (ehci, qh_get (qh));
1037 done:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001038 spin_unlock_irqrestore (&ehci->lock, flags);
Benjamin Herrenschmidt8de98402005-11-25 09:59:46 +11001039 if (unlikely (qh == NULL))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001040 qtd_list_free (ehci, urb, qtd_list);
Benjamin Herrenschmidt8de98402005-11-25 09:59:46 +11001041 return rc;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001042}
1043
1044/*-------------------------------------------------------------------------*/
1045
1046/* the async qh for the qtds being reclaimed are now unlinked from the HC */
1047
David Howells7d12e782006-10-05 14:55:46 +01001048static void end_unlink_async (struct ehci_hcd *ehci)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001049{
1050 struct ehci_qh *qh = ehci->reclaim;
1051 struct ehci_qh *next;
1052
Alan Stern07d29b62007-12-11 16:05:30 -05001053 iaa_watchdog_done(ehci);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001054
Stefan Roese6dbd6822007-05-01 09:29:37 -07001055 // qh->hw_next = cpu_to_hc32(qh->qh_dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001056 qh->qh_state = QH_STATE_IDLE;
1057 qh->qh_next.qh = NULL;
David Brownell53bd6a62006-08-30 14:50:06 -07001058 qh_put (qh); // refcount from reclaim
Linus Torvalds1da177e2005-04-16 15:20:36 -07001059
1060 /* other unlink(s) may be pending (in QH_STATE_UNLINK_WAIT) */
1061 next = qh->reclaim;
1062 ehci->reclaim = next;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001063 qh->reclaim = NULL;
1064
David Howells7d12e782006-10-05 14:55:46 +01001065 qh_completions (ehci, qh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001066
1067 if (!list_empty (&qh->qtd_list)
1068 && HC_IS_RUNNING (ehci_to_hcd(ehci)->state))
1069 qh_link_async (ehci, qh);
1070 else {
1071 qh_put (qh); // refcount from async list
1072
1073 /* it's not free to turn the async schedule on/off; leave it
1074 * active but idle for a while once it empties.
1075 */
1076 if (HC_IS_RUNNING (ehci_to_hcd(ehci)->state)
1077 && ehci->async->qh_next.qh == NULL)
1078 timer_action (ehci, TIMER_ASYNC_OFF);
1079 }
1080
1081 if (next) {
1082 ehci->reclaim = NULL;
1083 start_unlink_async (ehci, next);
1084 }
1085}
1086
1087/* makes sure the async qh will become idle */
1088/* caller must own ehci->lock */
1089
1090static void start_unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh)
1091{
Benjamin Herrenschmidt083522d2006-12-15 06:54:08 +11001092 int cmd = ehci_readl(ehci, &ehci->regs->command);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001093 struct ehci_qh *prev;
1094
1095#ifdef DEBUG
1096 assert_spin_locked(&ehci->lock);
1097 if (ehci->reclaim
1098 || (qh->qh_state != QH_STATE_LINKED
1099 && qh->qh_state != QH_STATE_UNLINK_WAIT)
1100 )
1101 BUG ();
1102#endif
1103
1104 /* stop async schedule right now? */
1105 if (unlikely (qh == ehci->async)) {
1106 /* can't get here without STS_ASS set */
David Brownelld0852292006-01-20 14:35:55 -08001107 if (ehci_to_hcd(ehci)->state != HC_STATE_HALT
1108 && !ehci->reclaim) {
1109 /* ... and CMD_IAAD clear */
Benjamin Herrenschmidt083522d2006-12-15 06:54:08 +11001110 ehci_writel(ehci, cmd & ~CMD_ASE,
1111 &ehci->regs->command);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001112 wmb ();
1113 // handshake later, if we need to
David Brownelld0852292006-01-20 14:35:55 -08001114 timer_action_done (ehci, TIMER_ASYNC_OFF);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001115 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001116 return;
David Brownell53bd6a62006-08-30 14:50:06 -07001117 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001118
1119 qh->qh_state = QH_STATE_UNLINK;
1120 ehci->reclaim = qh = qh_get (qh);
1121
1122 prev = ehci->async;
1123 while (prev->qh_next.qh != qh)
1124 prev = prev->qh_next.qh;
1125
1126 prev->hw_next = qh->hw_next;
1127 prev->qh_next = qh->qh_next;
1128 wmb ();
1129
Alan Stern391016f2009-03-16 14:21:56 -04001130 /* If the controller isn't running, we don't have to wait for it */
1131 if (unlikely(!HC_IS_RUNNING(ehci_to_hcd(ehci)->state))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001132 /* if (unlikely (qh->reclaim != 0))
David Brownell53bd6a62006-08-30 14:50:06 -07001133 * this will recurse, probably not much
Linus Torvalds1da177e2005-04-16 15:20:36 -07001134 */
David Howells7d12e782006-10-05 14:55:46 +01001135 end_unlink_async (ehci);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001136 return;
1137 }
1138
Linus Torvalds1da177e2005-04-16 15:20:36 -07001139 cmd |= CMD_IAAD;
Benjamin Herrenschmidt083522d2006-12-15 06:54:08 +11001140 ehci_writel(ehci, cmd, &ehci->regs->command);
1141 (void)ehci_readl(ehci, &ehci->regs->command);
Alan Stern07d29b62007-12-11 16:05:30 -05001142 iaa_watchdog_start(ehci);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001143}
1144
1145/*-------------------------------------------------------------------------*/
1146
David Howells7d12e782006-10-05 14:55:46 +01001147static void scan_async (struct ehci_hcd *ehci)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001148{
1149 struct ehci_qh *qh;
1150 enum ehci_timer_action action = TIMER_IO_WATCHDOG;
1151
David Brownellb9638012008-06-03 22:21:55 -07001152 ehci->stamp = ehci_readl(ehci, &ehci->regs->frame_index);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001153 timer_action_done (ehci, TIMER_ASYNC_SHRINK);
1154rescan:
1155 qh = ehci->async->qh_next.qh;
1156 if (likely (qh != NULL)) {
1157 do {
1158 /* clean any finished work for this qh */
1159 if (!list_empty (&qh->qtd_list)
1160 && qh->stamp != ehci->stamp) {
1161 int temp;
1162
1163 /* unlinks could happen here; completion
1164 * reporting drops the lock. rescan using
1165 * the latest schedule, but don't rescan
1166 * qhs we already finished (no looping).
1167 */
1168 qh = qh_get (qh);
1169 qh->stamp = ehci->stamp;
David Howells7d12e782006-10-05 14:55:46 +01001170 temp = qh_completions (ehci, qh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001171 qh_put (qh);
1172 if (temp != 0) {
1173 goto rescan;
1174 }
1175 }
1176
David Brownellb9638012008-06-03 22:21:55 -07001177 /* unlink idle entries, reducing DMA usage as well
Linus Torvalds1da177e2005-04-16 15:20:36 -07001178 * as HCD schedule-scanning costs. delay for any qh
1179 * we just scanned, there's a not-unusual case that it
1180 * doesn't stay idle for long.
1181 * (plus, avoids some kind of re-activation race.)
1182 */
David Brownellb9638012008-06-03 22:21:55 -07001183 if (list_empty(&qh->qtd_list)
1184 && qh->qh_state == QH_STATE_LINKED) {
1185 if (!ehci->reclaim
1186 && ((ehci->stamp - qh->stamp) & 0x1fff)
1187 >= (EHCI_SHRINK_FRAMES * 8))
1188 start_unlink_async(ehci, qh);
1189 else
Linus Torvalds1da177e2005-04-16 15:20:36 -07001190 action = TIMER_ASYNC_SHRINK;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001191 }
1192
1193 qh = qh->qh_next.qh;
1194 } while (qh);
1195 }
1196 if (action == TIMER_ASYNC_SHRINK)
1197 timer_action (ehci, TIMER_ASYNC_SHRINK);
1198}