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pzl.c
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1 /*
2  * Wireless Host Controller (WHC) periodic schedule 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/gfp.h>
20 #include <linux/dma-mapping.h>
21 #include <linux/uwb/umc.h>
22 #include <linux/usb.h>
23 
24 #include "../../wusbcore/wusbhc.h"
25 
26 #include "whcd.h"
27 
28 static void update_pzl_pointers(struct whc *whc, int period, u64 addr)
29 {
30  switch (period) {
31  case 0:
32  whc_qset_set_link_ptr(&whc->pz_list[0], addr);
33  whc_qset_set_link_ptr(&whc->pz_list[2], addr);
34  whc_qset_set_link_ptr(&whc->pz_list[4], addr);
35  whc_qset_set_link_ptr(&whc->pz_list[6], addr);
36  whc_qset_set_link_ptr(&whc->pz_list[8], addr);
37  whc_qset_set_link_ptr(&whc->pz_list[10], addr);
38  whc_qset_set_link_ptr(&whc->pz_list[12], addr);
39  whc_qset_set_link_ptr(&whc->pz_list[14], addr);
40  break;
41  case 1:
42  whc_qset_set_link_ptr(&whc->pz_list[1], addr);
43  whc_qset_set_link_ptr(&whc->pz_list[5], addr);
44  whc_qset_set_link_ptr(&whc->pz_list[9], addr);
45  whc_qset_set_link_ptr(&whc->pz_list[13], addr);
46  break;
47  case 2:
48  whc_qset_set_link_ptr(&whc->pz_list[3], addr);
49  whc_qset_set_link_ptr(&whc->pz_list[11], addr);
50  break;
51  case 3:
52  whc_qset_set_link_ptr(&whc->pz_list[7], addr);
53  break;
54  case 4:
55  whc_qset_set_link_ptr(&whc->pz_list[15], addr);
56  break;
57  }
58 }
59 
60 /*
61  * Return the 'period' to use for this qset. The minimum interval for
62  * the endpoint is used so whatever urbs are submitted the device is
63  * polled often enough.
64  */
65 static int qset_get_period(struct whc *whc, struct whc_qset *qset)
66 {
67  uint8_t bInterval = qset->ep->desc.bInterval;
68 
69  if (bInterval < 6)
70  bInterval = 6;
71  if (bInterval > 10)
72  bInterval = 10;
73  return bInterval - 6;
74 }
75 
76 static void qset_insert_in_sw_list(struct whc *whc, struct whc_qset *qset)
77 {
78  int period;
79 
80  period = qset_get_period(whc, qset);
81 
82  qset_clear(whc, qset);
83  list_move(&qset->list_node, &whc->periodic_list[period]);
84  qset->in_sw_list = true;
85 }
86 
87 static void pzl_qset_remove(struct whc *whc, struct whc_qset *qset)
88 {
89  list_move(&qset->list_node, &whc->periodic_removed_list);
90  qset->in_hw_list = false;
91  qset->in_sw_list = false;
92 }
93 
103 static enum whc_update pzl_process_qset(struct whc *whc, struct whc_qset *qset)
104 {
105  enum whc_update update = 0;
106  uint32_t status = 0;
107 
108  while (qset->ntds) {
109  struct whc_qtd *td;
110  int t;
111 
112  t = qset->td_start;
113  td = &qset->qtd[qset->td_start];
114  status = le32_to_cpu(td->status);
115 
116  /*
117  * Nothing to do with a still active qTD.
118  */
119  if (status & QTD_STS_ACTIVE)
120  break;
121 
122  if (status & QTD_STS_HALTED) {
123  /* Ug, an error. */
124  process_halted_qtd(whc, qset, td);
125  /* A halted qTD always triggers an update
126  because the qset was either removed or
127  reactivated. */
128  update |= WHC_UPDATE_UPDATED;
129  goto done;
130  }
131 
132  /* Mmm, a completed qTD. */
133  process_inactive_qtd(whc, qset, td);
134  }
135 
136  if (!qset->remove)
137  update |= qset_add_qtds(whc, qset);
138 
139 done:
140  /*
141  * If there are no qTDs in this qset, remove it from the PZL.
142  */
143  if (qset->remove && qset->ntds == 0) {
144  pzl_qset_remove(whc, qset);
145  update |= WHC_UPDATE_REMOVED;
146  }
147 
148  return update;
149 }
150 
158 void pzl_start(struct whc *whc)
159 {
160  le_writeq(whc->pz_list_dma, whc->base + WUSBPERIODICLISTBASE);
161 
163  whci_wait_for(&whc->umc->dev, whc->base + WUSBSTS,
165  1000, "start PZL");
166 }
167 
172 void pzl_stop(struct whc *whc)
173 {
175  whci_wait_for(&whc->umc->dev, whc->base + WUSBSTS,
177  1000, "stop PZL");
178 }
179 
189 void pzl_update(struct whc *whc, uint32_t wusbcmd)
190 {
191  struct wusbhc *wusbhc = &whc->wusbhc;
192  long t;
193 
194  mutex_lock(&wusbhc->mutex);
195  if (wusbhc->active) {
196  whc_write_wusbcmd(whc, wusbcmd, wusbcmd);
197  t = wait_event_timeout(
198  whc->periodic_list_wq,
199  (le_readl(whc->base + WUSBCMD) & WUSBCMD_PERIODIC_UPDATED) == 0,
200  msecs_to_jiffies(1000));
201  if (t == 0)
202  whc_hw_error(whc, "PZL update timeout");
203  }
204  mutex_unlock(&wusbhc->mutex);
205 }
206 
207 static void update_pzl_hw_view(struct whc *whc)
208 {
209  struct whc_qset *qset, *t;
210  int period;
211  u64 tmp_qh = 0;
212 
213  for (period = 0; period < 5; period++) {
214  list_for_each_entry_safe(qset, t, &whc->periodic_list[period], list_node) {
215  whc_qset_set_link_ptr(&qset->qh.link, tmp_qh);
216  tmp_qh = qset->qset_dma;
217  qset->in_hw_list = true;
218  }
219  update_pzl_pointers(whc, period, tmp_qh);
220  }
221 }
222 
232 {
233  struct whc *whc = container_of(work, struct whc, periodic_work);
234  struct whc_qset *qset, *t;
235  enum whc_update update = 0;
236  int period;
237 
238  spin_lock_irq(&whc->lock);
239 
240  for (period = 4; period >= 0; period--) {
241  list_for_each_entry_safe(qset, t, &whc->periodic_list[period], list_node) {
242  if (!qset->in_hw_list)
243  update |= WHC_UPDATE_ADDED;
244  update |= pzl_process_qset(whc, qset);
245  }
246  }
247 
248  if (update & (WHC_UPDATE_ADDED | WHC_UPDATE_REMOVED))
249  update_pzl_hw_view(whc);
250 
251  spin_unlock_irq(&whc->lock);
252 
253  if (update) {
255  if (update & WHC_UPDATE_REMOVED)
256  wusbcmd |= WUSBCMD_PERIODIC_QSET_RM;
257  pzl_update(whc, wusbcmd);
258  }
259 
260  /*
261  * Now that the PZL is updated, complete the removal of any
262  * removed qsets.
263  *
264  * If the qset was to be reset, do so and reinsert it into the
265  * PZL if it has pending transfers.
266  */
267  spin_lock_irq(&whc->lock);
268 
270  qset_remove_complete(whc, qset);
271  if (qset->reset) {
272  qset_reset(whc, qset);
273  if (!list_empty(&qset->stds)) {
274  qset_insert_in_sw_list(whc, qset);
275  queue_work(whc->workqueue, &whc->periodic_work);
276  }
277  }
278  }
279 
280  spin_unlock_irq(&whc->lock);
281 }
282 
293 int pzl_urb_enqueue(struct whc *whc, struct urb *urb, gfp_t mem_flags)
294 {
295  struct whc_qset *qset;
296  int err;
297  unsigned long flags;
298 
299  spin_lock_irqsave(&whc->lock, flags);
300 
301  err = usb_hcd_link_urb_to_ep(&whc->wusbhc.usb_hcd, urb);
302  if (err < 0) {
303  spin_unlock_irqrestore(&whc->lock, flags);
304  return err;
305  }
306 
307  qset = get_qset(whc, urb, GFP_ATOMIC);
308  if (qset == NULL)
309  err = -ENOMEM;
310  else
311  err = qset_add_urb(whc, qset, urb, GFP_ATOMIC);
312  if (!err) {
313  if (!qset->in_sw_list && !qset->remove)
314  qset_insert_in_sw_list(whc, qset);
315  } else
316  usb_hcd_unlink_urb_from_ep(&whc->wusbhc.usb_hcd, urb);
317 
318  spin_unlock_irqrestore(&whc->lock, flags);
319 
320  if (!err)
321  queue_work(whc->workqueue, &whc->periodic_work);
322 
323  return err;
324 }
325 
336 int pzl_urb_dequeue(struct whc *whc, struct urb *urb, int status)
337 {
338  struct whc_urb *wurb = urb->hcpriv;
339  struct whc_qset *qset = wurb->qset;
340  struct whc_std *std, *t;
341  bool has_qtd = false;
342  int ret;
343  unsigned long flags;
344 
345  spin_lock_irqsave(&whc->lock, flags);
346 
347  ret = usb_hcd_check_unlink_urb(&whc->wusbhc.usb_hcd, urb, status);
348  if (ret < 0)
349  goto out;
350 
351  list_for_each_entry_safe(std, t, &qset->stds, list_node) {
352  if (std->urb == urb) {
353  if (std->qtd)
354  has_qtd = true;
355  qset_free_std(whc, std);
356  } else
357  std->qtd = NULL; /* so this std is re-added when the qset is */
358  }
359 
360  if (has_qtd) {
361  pzl_qset_remove(whc, qset);
362  update_pzl_hw_view(whc);
363  wurb->status = status;
364  wurb->is_async = false;
365  queue_work(whc->workqueue, &wurb->dequeue_work);
366  } else
367  qset_remove_urb(whc, qset, urb, status);
368 out:
369  spin_unlock_irqrestore(&whc->lock, flags);
370 
371  return ret;
372 }
373 
377 void pzl_qset_delete(struct whc *whc, struct whc_qset *qset)
378 {
379  qset->remove = 1;
380  queue_work(whc->workqueue, &whc->periodic_work);
381  qset_delete(whc, qset);
382 }
383 
388 int pzl_init(struct whc *whc)
389 {
390  int i;
391 
392  whc->pz_list = dma_alloc_coherent(&whc->umc->dev, sizeof(u64) * 16,
393  &whc->pz_list_dma, GFP_KERNEL);
394  if (whc->pz_list == NULL)
395  return -ENOMEM;
396 
397  /* Set T bit on all elements in PZL. */
398  for (i = 0; i < 16; i++)
399  whc->pz_list[i] = cpu_to_le64(QH_LINK_NTDS(8) | QH_LINK_T);
400 
401  le_writeq(whc->pz_list_dma, whc->base + WUSBPERIODICLISTBASE);
402 
403  return 0;
404 }
405 
412 void pzl_clean_up(struct whc *whc)
413 {
414  if (whc->pz_list)
415  dma_free_coherent(&whc->umc->dev, sizeof(u64) * 16, whc->pz_list,
416  whc->pz_list_dma);
417 }