1 /*
2 * Wireless Host Controller (WHC) qset management.
3 *
4 * Copyright (C) 2007 Cambridge Silicon Radio Ltd.
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License version
8 * 2 as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
17 */
18 #include <linux/kernel.h>
19 #include <linux/dma-mapping.h>
20 #include <linux/uwb/umc.h>
21 #include <linux/usb.h>
22
23 #include "../../wusbcore/wusbhc.h"
24
25 #include "whcd.h"
26
qset_alloc(struct whc * whc,gfp_t mem_flags)27 struct whc_qset *qset_alloc(struct whc *whc, gfp_t mem_flags)
28 {
29 struct whc_qset *qset;
30 dma_addr_t dma;
31
32 qset = dma_pool_alloc(whc->qset_pool, mem_flags, &dma);
33 if (qset == NULL)
34 return NULL;
35 memset(qset, 0, sizeof(struct whc_qset));
36
37 qset->qset_dma = dma;
38 qset->whc = whc;
39
40 INIT_LIST_HEAD(&qset->list_node);
41 INIT_LIST_HEAD(&qset->stds);
42
43 return qset;
44 }
45
46 /**
47 * qset_fill_qh - fill the static endpoint state in a qset's QHead
48 * @qset: the qset whose QH needs initializing with static endpoint
49 * state
50 * @urb: an urb for a transfer to this endpoint
51 */
qset_fill_qh(struct whc_qset * qset,struct urb * urb)52 static void qset_fill_qh(struct whc_qset *qset, struct urb *urb)
53 {
54 struct usb_device *usb_dev = urb->dev;
55 struct usb_wireless_ep_comp_descriptor *epcd;
56 bool is_out;
57
58 is_out = usb_pipeout(urb->pipe);
59
60 epcd = (struct usb_wireless_ep_comp_descriptor *)qset->ep->extra;
61
62 if (epcd) {
63 qset->max_seq = epcd->bMaxSequence;
64 qset->max_burst = epcd->bMaxBurst;
65 } else {
66 qset->max_seq = 2;
67 qset->max_burst = 1;
68 }
69
70 qset->qh.info1 = cpu_to_le32(
71 QH_INFO1_EP(usb_pipeendpoint(urb->pipe))
72 | (is_out ? QH_INFO1_DIR_OUT : QH_INFO1_DIR_IN)
73 | usb_pipe_to_qh_type(urb->pipe)
74 | QH_INFO1_DEV_INFO_IDX(wusb_port_no_to_idx(usb_dev->portnum))
75 | QH_INFO1_MAX_PKT_LEN(usb_maxpacket(urb->dev, urb->pipe, is_out))
76 );
77 qset->qh.info2 = cpu_to_le32(
78 QH_INFO2_BURST(qset->max_burst)
79 | QH_INFO2_DBP(0)
80 | QH_INFO2_MAX_COUNT(3)
81 | QH_INFO2_MAX_RETRY(3)
82 | QH_INFO2_MAX_SEQ(qset->max_seq - 1)
83 );
84 /* FIXME: where can we obtain these Tx parameters from? Why
85 * doesn't the chip know what Tx power to use? It knows the Rx
86 * strength and can presumably guess the Tx power required
87 * from that? */
88 qset->qh.info3 = cpu_to_le32(
89 QH_INFO3_TX_RATE_53_3
90 | QH_INFO3_TX_PWR(0) /* 0 == max power */
91 );
92 }
93
94 /**
95 * qset_clear - clear fields in a qset so it may be reinserted into a
96 * schedule
97 */
qset_clear(struct whc * whc,struct whc_qset * qset)98 void qset_clear(struct whc *whc, struct whc_qset *qset)
99 {
100 qset->td_start = qset->td_end = qset->ntds = 0;
101 qset->remove = 0;
102
103 qset->qh.link = cpu_to_le32(QH_LINK_NTDS(8) | QH_LINK_T);
104 qset->qh.status = cpu_to_le16(QH_STATUS_ICUR(qset->td_start));
105 qset->qh.err_count = 0;
106 qset->qh.cur_window = cpu_to_le32((1 << qset->max_burst) - 1);
107 qset->qh.scratch[0] = 0;
108 qset->qh.scratch[1] = 0;
109 qset->qh.scratch[2] = 0;
110
111 memset(&qset->qh.overlay, 0, sizeof(qset->qh.overlay));
112
113 init_completion(&qset->remove_complete);
114 }
115
116 /**
117 * get_qset - get the qset for an async endpoint
118 *
119 * A new qset is created if one does not already exist.
120 */
get_qset(struct whc * whc,struct urb * urb,gfp_t mem_flags)121 struct whc_qset *get_qset(struct whc *whc, struct urb *urb,
122 gfp_t mem_flags)
123 {
124 struct whc_qset *qset;
125
126 qset = urb->ep->hcpriv;
127 if (qset == NULL) {
128 qset = qset_alloc(whc, mem_flags);
129 if (qset == NULL)
130 return NULL;
131
132 qset->ep = urb->ep;
133 urb->ep->hcpriv = qset;
134 qset_fill_qh(qset, urb);
135 }
136 return qset;
137 }
138
qset_remove_complete(struct whc * whc,struct whc_qset * qset)139 void qset_remove_complete(struct whc *whc, struct whc_qset *qset)
140 {
141 list_del_init(&qset->list_node);
142 complete(&qset->remove_complete);
143 }
144
145 /**
146 * qset_add_qtds - add qTDs for an URB to a qset
147 *
148 * Returns true if the list (ASL/PZL) must be updated because (for a
149 * WHCI 0.95 controller) an activated qTD was pointed to be iCur.
150 */
qset_add_qtds(struct whc * whc,struct whc_qset * qset)151 enum whc_update qset_add_qtds(struct whc *whc, struct whc_qset *qset)
152 {
153 struct whc_std *std;
154 enum whc_update update = 0;
155
156 list_for_each_entry(std, &qset->stds, list_node) {
157 struct whc_qtd *qtd;
158 uint32_t status;
159
160 if (qset->ntds >= WHCI_QSET_TD_MAX
161 || (qset->pause_after_urb && std->urb != qset->pause_after_urb))
162 break;
163
164 if (std->qtd)
165 continue; /* already has a qTD */
166
167 qtd = std->qtd = &qset->qtd[qset->td_end];
168
169 /* Fill in setup bytes for control transfers. */
170 if (usb_pipecontrol(std->urb->pipe))
171 memcpy(qtd->setup, std->urb->setup_packet, 8);
172
173 status = QTD_STS_ACTIVE | QTD_STS_LEN(std->len);
174
175 if (whc_std_last(std) && usb_pipeout(std->urb->pipe))
176 status |= QTD_STS_LAST_PKT;
177
178 /*
179 * For an IN transfer the iAlt field should be set so
180 * the h/w will automatically advance to the next
181 * transfer. However, if there are 8 or more TDs
182 * remaining in this transfer then iAlt cannot be set
183 * as it could point to somewhere in this transfer.
184 */
185 if (std->ntds_remaining < WHCI_QSET_TD_MAX) {
186 int ialt;
187 ialt = (qset->td_end + std->ntds_remaining) % WHCI_QSET_TD_MAX;
188 status |= QTD_STS_IALT(ialt);
189 } else if (usb_pipein(std->urb->pipe))
190 qset->pause_after_urb = std->urb;
191
192 if (std->num_pointers)
193 qtd->options = cpu_to_le32(QTD_OPT_IOC);
194 else
195 qtd->options = cpu_to_le32(QTD_OPT_IOC | QTD_OPT_SMALL);
196 qtd->page_list_ptr = cpu_to_le64(std->dma_addr);
197
198 qtd->status = cpu_to_le32(status);
199
200 if (QH_STATUS_TO_ICUR(qset->qh.status) == qset->td_end)
201 update = WHC_UPDATE_UPDATED;
202
203 if (++qset->td_end >= WHCI_QSET_TD_MAX)
204 qset->td_end = 0;
205 qset->ntds++;
206 }
207
208 return update;
209 }
210
211 /**
212 * qset_remove_qtd - remove the first qTD from a qset.
213 *
214 * The qTD might be still active (if it's part of a IN URB that
215 * resulted in a short read) so ensure it's deactivated.
216 */
qset_remove_qtd(struct whc * whc,struct whc_qset * qset)217 static void qset_remove_qtd(struct whc *whc, struct whc_qset *qset)
218 {
219 qset->qtd[qset->td_start].status = 0;
220
221 if (++qset->td_start >= WHCI_QSET_TD_MAX)
222 qset->td_start = 0;
223 qset->ntds--;
224 }
225
226 /**
227 * qset_free_std - remove an sTD and free it.
228 * @whc: the WHCI host controller
229 * @std: the sTD to remove and free.
230 */
qset_free_std(struct whc * whc,struct whc_std * std)231 void qset_free_std(struct whc *whc, struct whc_std *std)
232 {
233 list_del(&std->list_node);
234 if (std->num_pointers) {
235 dma_unmap_single(whc->wusbhc.dev, std->dma_addr,
236 std->num_pointers * sizeof(struct whc_page_list_entry),
237 DMA_TO_DEVICE);
238 kfree(std->pl_virt);
239 }
240
241 kfree(std);
242 }
243
244 /**
245 * qset_remove_qtds - remove an URB's qTDs (and sTDs).
246 */
qset_remove_qtds(struct whc * whc,struct whc_qset * qset,struct urb * urb)247 static void qset_remove_qtds(struct whc *whc, struct whc_qset *qset,
248 struct urb *urb)
249 {
250 struct whc_std *std, *t;
251
252 list_for_each_entry_safe(std, t, &qset->stds, list_node) {
253 if (std->urb != urb)
254 break;
255 if (std->qtd != NULL)
256 qset_remove_qtd(whc, qset);
257 qset_free_std(whc, std);
258 }
259 }
260
261 /**
262 * qset_free_stds - free any remaining sTDs for an URB.
263 */
qset_free_stds(struct whc_qset * qset,struct urb * urb)264 static void qset_free_stds(struct whc_qset *qset, struct urb *urb)
265 {
266 struct whc_std *std, *t;
267
268 list_for_each_entry_safe(std, t, &qset->stds, list_node) {
269 if (std->urb == urb)
270 qset_free_std(qset->whc, std);
271 }
272 }
273
qset_fill_page_list(struct whc * whc,struct whc_std * std,gfp_t mem_flags)274 static int qset_fill_page_list(struct whc *whc, struct whc_std *std, gfp_t mem_flags)
275 {
276 dma_addr_t dma_addr = std->dma_addr;
277 dma_addr_t sp, ep;
278 size_t std_len = std->len;
279 size_t pl_len;
280 int p;
281
282 sp = ALIGN(dma_addr, WHCI_PAGE_SIZE);
283 ep = dma_addr + std_len;
284 std->num_pointers = DIV_ROUND_UP(ep - sp, WHCI_PAGE_SIZE);
285
286 pl_len = std->num_pointers * sizeof(struct whc_page_list_entry);
287 std->pl_virt = kmalloc(pl_len, mem_flags);
288 if (std->pl_virt == NULL)
289 return -ENOMEM;
290 std->dma_addr = dma_map_single(whc->wusbhc.dev, std->pl_virt, pl_len, DMA_TO_DEVICE);
291
292 for (p = 0; p < std->num_pointers; p++) {
293 std->pl_virt[p].buf_ptr = cpu_to_le64(dma_addr);
294 dma_addr = ALIGN(dma_addr + WHCI_PAGE_SIZE, WHCI_PAGE_SIZE);
295 }
296
297 return 0;
298 }
299
300 /**
301 * urb_dequeue_work - executes asl/pzl update and gives back the urb to the system.
302 */
urb_dequeue_work(struct work_struct * work)303 static void urb_dequeue_work(struct work_struct *work)
304 {
305 struct whc_urb *wurb = container_of(work, struct whc_urb, dequeue_work);
306 struct whc_qset *qset = wurb->qset;
307 struct whc *whc = qset->whc;
308 unsigned long flags;
309
310 if (wurb->is_async == true)
311 asl_update(whc, WUSBCMD_ASYNC_UPDATED
312 | WUSBCMD_ASYNC_SYNCED_DB
313 | WUSBCMD_ASYNC_QSET_RM);
314 else
315 pzl_update(whc, WUSBCMD_PERIODIC_UPDATED
316 | WUSBCMD_PERIODIC_SYNCED_DB
317 | WUSBCMD_PERIODIC_QSET_RM);
318
319 spin_lock_irqsave(&whc->lock, flags);
320 qset_remove_urb(whc, qset, wurb->urb, wurb->status);
321 spin_unlock_irqrestore(&whc->lock, flags);
322 }
323
324 /**
325 * qset_add_urb - add an urb to the qset's queue.
326 *
327 * The URB is chopped into sTDs, one for each qTD that will required.
328 * At least one qTD (and sTD) is required even if the transfer has no
329 * data (e.g., for some control transfers).
330 */
qset_add_urb(struct whc * whc,struct whc_qset * qset,struct urb * urb,gfp_t mem_flags)331 int qset_add_urb(struct whc *whc, struct whc_qset *qset, struct urb *urb,
332 gfp_t mem_flags)
333 {
334 struct whc_urb *wurb;
335 int remaining = urb->transfer_buffer_length;
336 u64 transfer_dma = urb->transfer_dma;
337 int ntds_remaining;
338
339 ntds_remaining = DIV_ROUND_UP(remaining, QTD_MAX_XFER_SIZE);
340 if (ntds_remaining == 0)
341 ntds_remaining = 1;
342
343 wurb = kzalloc(sizeof(struct whc_urb), mem_flags);
344 if (wurb == NULL)
345 goto err_no_mem;
346 urb->hcpriv = wurb;
347 wurb->qset = qset;
348 wurb->urb = urb;
349 INIT_WORK(&wurb->dequeue_work, urb_dequeue_work);
350
351 while (ntds_remaining) {
352 struct whc_std *std;
353 size_t std_len;
354
355 std = kmalloc(sizeof(struct whc_std), mem_flags);
356 if (std == NULL)
357 goto err_no_mem;
358
359 std_len = remaining;
360 if (std_len > QTD_MAX_XFER_SIZE)
361 std_len = QTD_MAX_XFER_SIZE;
362
363 std->urb = urb;
364 std->dma_addr = transfer_dma;
365 std->len = std_len;
366 std->ntds_remaining = ntds_remaining;
367 std->qtd = NULL;
368
369 INIT_LIST_HEAD(&std->list_node);
370 list_add_tail(&std->list_node, &qset->stds);
371
372 if (std_len > WHCI_PAGE_SIZE) {
373 if (qset_fill_page_list(whc, std, mem_flags) < 0)
374 goto err_no_mem;
375 } else
376 std->num_pointers = 0;
377
378 ntds_remaining--;
379 remaining -= std_len;
380 transfer_dma += std_len;
381 }
382
383 return 0;
384
385 err_no_mem:
386 qset_free_stds(qset, urb);
387 return -ENOMEM;
388 }
389
390 /**
391 * qset_remove_urb - remove an URB from the urb queue.
392 *
393 * The URB is returned to the USB subsystem.
394 */
qset_remove_urb(struct whc * whc,struct whc_qset * qset,struct urb * urb,int status)395 void qset_remove_urb(struct whc *whc, struct whc_qset *qset,
396 struct urb *urb, int status)
397 {
398 struct wusbhc *wusbhc = &whc->wusbhc;
399 struct whc_urb *wurb = urb->hcpriv;
400
401 usb_hcd_unlink_urb_from_ep(&wusbhc->usb_hcd, urb);
402 /* Drop the lock as urb->complete() may enqueue another urb. */
403 spin_unlock(&whc->lock);
404 wusbhc_giveback_urb(wusbhc, urb, status);
405 spin_lock(&whc->lock);
406
407 kfree(wurb);
408 }
409
410 /**
411 * get_urb_status_from_qtd - get the completed urb status from qTD status
412 * @urb: completed urb
413 * @status: qTD status
414 */
get_urb_status_from_qtd(struct urb * urb,u32 status)415 static int get_urb_status_from_qtd(struct urb *urb, u32 status)
416 {
417 if (status & QTD_STS_HALTED) {
418 if (status & QTD_STS_DBE)
419 return usb_pipein(urb->pipe) ? -ENOSR : -ECOMM;
420 else if (status & QTD_STS_BABBLE)
421 return -EOVERFLOW;
422 else if (status & QTD_STS_RCE)
423 return -ETIME;
424 return -EPIPE;
425 }
426 if (usb_pipein(urb->pipe)
427 && (urb->transfer_flags & URB_SHORT_NOT_OK)
428 && urb->actual_length < urb->transfer_buffer_length)
429 return -EREMOTEIO;
430 return 0;
431 }
432
433 /**
434 * process_inactive_qtd - process an inactive (but not halted) qTD.
435 *
436 * Update the urb with the transfer bytes from the qTD, if the urb is
437 * completely transfered or (in the case of an IN only) the LPF is
438 * set, then the transfer is complete and the urb should be returned
439 * to the system.
440 */
process_inactive_qtd(struct whc * whc,struct whc_qset * qset,struct whc_qtd * qtd)441 void process_inactive_qtd(struct whc *whc, struct whc_qset *qset,
442 struct whc_qtd *qtd)
443 {
444 struct whc_std *std = list_first_entry(&qset->stds, struct whc_std, list_node);
445 struct urb *urb = std->urb;
446 uint32_t status;
447 bool complete;
448
449 status = le32_to_cpu(qtd->status);
450
451 urb->actual_length += std->len - QTD_STS_TO_LEN(status);
452
453 if (usb_pipein(urb->pipe) && (status & QTD_STS_LAST_PKT))
454 complete = true;
455 else
456 complete = whc_std_last(std);
457
458 qset_remove_qtd(whc, qset);
459 qset_free_std(whc, std);
460
461 /*
462 * Transfers for this URB are complete? Then return it to the
463 * USB subsystem.
464 */
465 if (complete) {
466 qset_remove_qtds(whc, qset, urb);
467 qset_remove_urb(whc, qset, urb, get_urb_status_from_qtd(urb, status));
468
469 /*
470 * If iAlt isn't valid then the hardware didn't
471 * advance iCur. Adjust the start and end pointers to
472 * match iCur.
473 */
474 if (!(status & QTD_STS_IALT_VALID))
475 qset->td_start = qset->td_end
476 = QH_STATUS_TO_ICUR(le16_to_cpu(qset->qh.status));
477 qset->pause_after_urb = NULL;
478 }
479 }
480
481 /**
482 * process_halted_qtd - process a qset with a halted qtd
483 *
484 * Remove all the qTDs for the failed URB and return the failed URB to
485 * the USB subsystem. Then remove all other qTDs so the qset can be
486 * removed.
487 *
488 * FIXME: this is the point where rate adaptation can be done. If a
489 * transfer failed because it exceeded the maximum number of retries
490 * then it could be reactivated with a slower rate without having to
491 * remove the qset.
492 */
process_halted_qtd(struct whc * whc,struct whc_qset * qset,struct whc_qtd * qtd)493 void process_halted_qtd(struct whc *whc, struct whc_qset *qset,
494 struct whc_qtd *qtd)
495 {
496 struct whc_std *std = list_first_entry(&qset->stds, struct whc_std, list_node);
497 struct urb *urb = std->urb;
498 int urb_status;
499
500 urb_status = get_urb_status_from_qtd(urb, le32_to_cpu(qtd->status));
501
502 qset_remove_qtds(whc, qset, urb);
503 qset_remove_urb(whc, qset, urb, urb_status);
504
505 list_for_each_entry(std, &qset->stds, list_node) {
506 if (qset->ntds == 0)
507 break;
508 qset_remove_qtd(whc, qset);
509 std->qtd = NULL;
510 }
511
512 qset->remove = 1;
513 }
514
qset_free(struct whc * whc,struct whc_qset * qset)515 void qset_free(struct whc *whc, struct whc_qset *qset)
516 {
517 dma_pool_free(whc->qset_pool, qset, qset->qset_dma);
518 }
519
520 /**
521 * qset_delete - wait for a qset to be unused, then free it.
522 */
qset_delete(struct whc * whc,struct whc_qset * qset)523 void qset_delete(struct whc *whc, struct whc_qset *qset)
524 {
525 wait_for_completion(&qset->remove_complete);
526 qset_free(whc, qset);
527 }
528