diff options
Diffstat (limited to 'kernel/drivers/usb/host/ehci-sched.c')
| -rw-r--r-- | kernel/drivers/usb/host/ehci-sched.c | 2517 |
1 files changed, 2517 insertions, 0 deletions
diff --git a/kernel/drivers/usb/host/ehci-sched.c b/kernel/drivers/usb/host/ehci-sched.c new file mode 100644 index 000000000..f9a332775 --- /dev/null +++ b/kernel/drivers/usb/host/ehci-sched.c @@ -0,0 +1,2517 @@ +/* + * Copyright (c) 2001-2004 by David Brownell + * Copyright (c) 2003 Michal Sojka, for high-speed iso transfers + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software Foundation, + * Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +/* this file is part of ehci-hcd.c */ + +/*-------------------------------------------------------------------------*/ + +/* + * EHCI scheduled transaction support: interrupt, iso, split iso + * These are called "periodic" transactions in the EHCI spec. + * + * Note that for interrupt transfers, the QH/QTD manipulation is shared + * with the "asynchronous" transaction support (control/bulk transfers). + * The only real difference is in how interrupt transfers are scheduled. + * + * For ISO, we make an "iso_stream" head to serve the same role as a QH. + * It keeps track of every ITD (or SITD) that's linked, and holds enough + * pre-calculated schedule data to make appending to the queue be quick. + */ + +static int ehci_get_frame (struct usb_hcd *hcd); + +/* + * periodic_next_shadow - return "next" pointer on shadow list + * @periodic: host pointer to qh/itd/sitd + * @tag: hardware tag for type of this record + */ +static union ehci_shadow * +periodic_next_shadow(struct ehci_hcd *ehci, union ehci_shadow *periodic, + __hc32 tag) +{ + switch (hc32_to_cpu(ehci, tag)) { + case Q_TYPE_QH: + return &periodic->qh->qh_next; + case Q_TYPE_FSTN: + return &periodic->fstn->fstn_next; + case Q_TYPE_ITD: + return &periodic->itd->itd_next; + // case Q_TYPE_SITD: + default: + return &periodic->sitd->sitd_next; + } +} + +static __hc32 * +shadow_next_periodic(struct ehci_hcd *ehci, union ehci_shadow *periodic, + __hc32 tag) +{ + switch (hc32_to_cpu(ehci, tag)) { + /* our ehci_shadow.qh is actually software part */ + case Q_TYPE_QH: + return &periodic->qh->hw->hw_next; + /* others are hw parts */ + default: + return periodic->hw_next; + } +} + +/* caller must hold ehci->lock */ +static void periodic_unlink (struct ehci_hcd *ehci, unsigned frame, void *ptr) +{ + union ehci_shadow *prev_p = &ehci->pshadow[frame]; + __hc32 *hw_p = &ehci->periodic[frame]; + union ehci_shadow here = *prev_p; + + /* find predecessor of "ptr"; hw and shadow lists are in sync */ + while (here.ptr && here.ptr != ptr) { + prev_p = periodic_next_shadow(ehci, prev_p, + Q_NEXT_TYPE(ehci, *hw_p)); + hw_p = shadow_next_periodic(ehci, &here, + Q_NEXT_TYPE(ehci, *hw_p)); + here = *prev_p; + } + /* an interrupt entry (at list end) could have been shared */ + if (!here.ptr) + return; + + /* update shadow and hardware lists ... the old "next" pointers + * from ptr may still be in use, the caller updates them. + */ + *prev_p = *periodic_next_shadow(ehci, &here, + Q_NEXT_TYPE(ehci, *hw_p)); + + if (!ehci->use_dummy_qh || + *shadow_next_periodic(ehci, &here, Q_NEXT_TYPE(ehci, *hw_p)) + != EHCI_LIST_END(ehci)) + *hw_p = *shadow_next_periodic(ehci, &here, + Q_NEXT_TYPE(ehci, *hw_p)); + else + *hw_p = cpu_to_hc32(ehci, ehci->dummy->qh_dma); +} + +/*-------------------------------------------------------------------------*/ + +/* Bandwidth and TT management */ + +/* Find the TT data structure for this device; create it if necessary */ +static struct ehci_tt *find_tt(struct usb_device *udev) +{ + struct usb_tt *utt = udev->tt; + struct ehci_tt *tt, **tt_index, **ptt; + unsigned port; + bool allocated_index = false; + + if (!utt) + return NULL; /* Not below a TT */ + + /* + * Find/create our data structure. + * For hubs with a single TT, we get it directly. + * For hubs with multiple TTs, there's an extra level of pointers. + */ + tt_index = NULL; + if (utt->multi) { + tt_index = utt->hcpriv; + if (!tt_index) { /* Create the index array */ + tt_index = kzalloc(utt->hub->maxchild * + sizeof(*tt_index), GFP_ATOMIC); + if (!tt_index) + return ERR_PTR(-ENOMEM); + utt->hcpriv = tt_index; + allocated_index = true; + } + port = udev->ttport - 1; + ptt = &tt_index[port]; + } else { + port = 0; + ptt = (struct ehci_tt **) &utt->hcpriv; + } + + tt = *ptt; + if (!tt) { /* Create the ehci_tt */ + struct ehci_hcd *ehci = + hcd_to_ehci(bus_to_hcd(udev->bus)); + + tt = kzalloc(sizeof(*tt), GFP_ATOMIC); + if (!tt) { + if (allocated_index) { + utt->hcpriv = NULL; + kfree(tt_index); + } + return ERR_PTR(-ENOMEM); + } + list_add_tail(&tt->tt_list, &ehci->tt_list); + INIT_LIST_HEAD(&tt->ps_list); + tt->usb_tt = utt; + tt->tt_port = port; + *ptt = tt; + } + + return tt; +} + +/* Release the TT above udev, if it's not in use */ +static void drop_tt(struct usb_device *udev) +{ + struct usb_tt *utt = udev->tt; + struct ehci_tt *tt, **tt_index, **ptt; + int cnt, i; + + if (!utt || !utt->hcpriv) + return; /* Not below a TT, or never allocated */ + + cnt = 0; + if (utt->multi) { + tt_index = utt->hcpriv; + ptt = &tt_index[udev->ttport - 1]; + + /* How many entries are left in tt_index? */ + for (i = 0; i < utt->hub->maxchild; ++i) + cnt += !!tt_index[i]; + } else { + tt_index = NULL; + ptt = (struct ehci_tt **) &utt->hcpriv; + } + + tt = *ptt; + if (!tt || !list_empty(&tt->ps_list)) + return; /* never allocated, or still in use */ + + list_del(&tt->tt_list); + *ptt = NULL; + kfree(tt); + if (cnt == 1) { + utt->hcpriv = NULL; + kfree(tt_index); + } +} + +static void bandwidth_dbg(struct ehci_hcd *ehci, int sign, char *type, + struct ehci_per_sched *ps) +{ + dev_dbg(&ps->udev->dev, + "ep %02x: %s %s @ %u+%u (%u.%u+%u) [%u/%u us] mask %04x\n", + ps->ep->desc.bEndpointAddress, + (sign >= 0 ? "reserve" : "release"), type, + (ps->bw_phase << 3) + ps->phase_uf, ps->bw_uperiod, + ps->phase, ps->phase_uf, ps->period, + ps->usecs, ps->c_usecs, ps->cs_mask); +} + +static void reserve_release_intr_bandwidth(struct ehci_hcd *ehci, + struct ehci_qh *qh, int sign) +{ + unsigned start_uf; + unsigned i, j, m; + int usecs = qh->ps.usecs; + int c_usecs = qh->ps.c_usecs; + int tt_usecs = qh->ps.tt_usecs; + struct ehci_tt *tt; + + if (qh->ps.phase == NO_FRAME) /* Bandwidth wasn't reserved */ + return; + start_uf = qh->ps.bw_phase << 3; + + bandwidth_dbg(ehci, sign, "intr", &qh->ps); + + if (sign < 0) { /* Release bandwidth */ + usecs = -usecs; + c_usecs = -c_usecs; + tt_usecs = -tt_usecs; + } + + /* Entire transaction (high speed) or start-split (full/low speed) */ + for (i = start_uf + qh->ps.phase_uf; i < EHCI_BANDWIDTH_SIZE; + i += qh->ps.bw_uperiod) + ehci->bandwidth[i] += usecs; + + /* Complete-split (full/low speed) */ + if (qh->ps.c_usecs) { + /* NOTE: adjustments needed for FSTN */ + for (i = start_uf; i < EHCI_BANDWIDTH_SIZE; + i += qh->ps.bw_uperiod) { + for ((j = 2, m = 1 << (j+8)); j < 8; (++j, m <<= 1)) { + if (qh->ps.cs_mask & m) + ehci->bandwidth[i+j] += c_usecs; + } + } + } + + /* FS/LS bus bandwidth */ + if (tt_usecs) { + tt = find_tt(qh->ps.udev); + if (sign > 0) + list_add_tail(&qh->ps.ps_list, &tt->ps_list); + else + list_del(&qh->ps.ps_list); + + for (i = start_uf >> 3; i < EHCI_BANDWIDTH_FRAMES; + i += qh->ps.bw_period) + tt->bandwidth[i] += tt_usecs; + } +} + +/*-------------------------------------------------------------------------*/ + +static void compute_tt_budget(u8 budget_table[EHCI_BANDWIDTH_SIZE], + struct ehci_tt *tt) +{ + struct ehci_per_sched *ps; + unsigned uframe, uf, x; + u8 *budget_line; + + if (!tt) + return; + memset(budget_table, 0, EHCI_BANDWIDTH_SIZE); + + /* Add up the contributions from all the endpoints using this TT */ + list_for_each_entry(ps, &tt->ps_list, ps_list) { + for (uframe = ps->bw_phase << 3; uframe < EHCI_BANDWIDTH_SIZE; + uframe += ps->bw_uperiod) { + budget_line = &budget_table[uframe]; + x = ps->tt_usecs; + + /* propagate the time forward */ + for (uf = ps->phase_uf; uf < 8; ++uf) { + x += budget_line[uf]; + + /* Each microframe lasts 125 us */ + if (x <= 125) { + budget_line[uf] = x; + break; + } else { + budget_line[uf] = 125; + x -= 125; + } + } + } + } +} + +static int __maybe_unused same_tt(struct usb_device *dev1, + struct usb_device *dev2) +{ + if (!dev1->tt || !dev2->tt) + return 0; + if (dev1->tt != dev2->tt) + return 0; + if (dev1->tt->multi) + return dev1->ttport == dev2->ttport; + else + return 1; +} + +#ifdef CONFIG_USB_EHCI_TT_NEWSCHED + +/* Which uframe does the low/fullspeed transfer start in? + * + * The parameter is the mask of ssplits in "H-frame" terms + * and this returns the transfer start uframe in "B-frame" terms, + * which allows both to match, e.g. a ssplit in "H-frame" uframe 0 + * will cause a transfer in "B-frame" uframe 0. "B-frames" lag + * "H-frames" by 1 uframe. See the EHCI spec sec 4.5 and figure 4.7. + */ +static inline unsigned char tt_start_uframe(struct ehci_hcd *ehci, __hc32 mask) +{ + unsigned char smask = QH_SMASK & hc32_to_cpu(ehci, mask); + if (!smask) { + ehci_err(ehci, "invalid empty smask!\n"); + /* uframe 7 can't have bw so this will indicate failure */ + return 7; + } + return ffs(smask) - 1; +} + +static const unsigned char +max_tt_usecs[] = { 125, 125, 125, 125, 125, 125, 30, 0 }; + +/* carryover low/fullspeed bandwidth that crosses uframe boundries */ +static inline void carryover_tt_bandwidth(unsigned short tt_usecs[8]) +{ + int i; + for (i=0; i<7; i++) { + if (max_tt_usecs[i] < tt_usecs[i]) { + tt_usecs[i+1] += tt_usecs[i] - max_tt_usecs[i]; + tt_usecs[i] = max_tt_usecs[i]; + } + } +} + +/* + * Return true if the device's tt's downstream bus is available for a + * periodic transfer of the specified length (usecs), starting at the + * specified frame/uframe. Note that (as summarized in section 11.19 + * of the usb 2.0 spec) TTs can buffer multiple transactions for each + * uframe. + * + * The uframe parameter is when the fullspeed/lowspeed transfer + * should be executed in "B-frame" terms, which is the same as the + * highspeed ssplit's uframe (which is in "H-frame" terms). For example + * a ssplit in "H-frame" 0 causes a transfer in "B-frame" 0. + * See the EHCI spec sec 4.5 and fig 4.7. + * + * This checks if the full/lowspeed bus, at the specified starting uframe, + * has the specified bandwidth available, according to rules listed + * in USB 2.0 spec section 11.18.1 fig 11-60. + * + * This does not check if the transfer would exceed the max ssplit + * limit of 16, specified in USB 2.0 spec section 11.18.4 requirement #4, + * since proper scheduling limits ssplits to less than 16 per uframe. + */ +static int tt_available ( + struct ehci_hcd *ehci, + struct ehci_per_sched *ps, + struct ehci_tt *tt, + unsigned frame, + unsigned uframe +) +{ + unsigned period = ps->bw_period; + unsigned usecs = ps->tt_usecs; + + if ((period == 0) || (uframe >= 7)) /* error */ + return 0; + + for (frame &= period - 1; frame < EHCI_BANDWIDTH_FRAMES; + frame += period) { + unsigned i, uf; + unsigned short tt_usecs[8]; + + if (tt->bandwidth[frame] + usecs > 900) + return 0; + + uf = frame << 3; + for (i = 0; i < 8; (++i, ++uf)) + tt_usecs[i] = ehci->tt_budget[uf]; + + if (max_tt_usecs[uframe] <= tt_usecs[uframe]) + return 0; + + /* special case for isoc transfers larger than 125us: + * the first and each subsequent fully used uframe + * must be empty, so as to not illegally delay + * already scheduled transactions + */ + if (125 < usecs) { + int ufs = (usecs / 125); + + for (i = uframe; i < (uframe + ufs) && i < 8; i++) + if (0 < tt_usecs[i]) + return 0; + } + + tt_usecs[uframe] += usecs; + + carryover_tt_bandwidth(tt_usecs); + + /* fail if the carryover pushed bw past the last uframe's limit */ + if (max_tt_usecs[7] < tt_usecs[7]) + return 0; + } + + return 1; +} + +#else + +/* return true iff the device's transaction translator is available + * for a periodic transfer starting at the specified frame, using + * all the uframes in the mask. + */ +static int tt_no_collision ( + struct ehci_hcd *ehci, + unsigned period, + struct usb_device *dev, + unsigned frame, + u32 uf_mask +) +{ + if (period == 0) /* error */ + return 0; + + /* note bandwidth wastage: split never follows csplit + * (different dev or endpoint) until the next uframe. + * calling convention doesn't make that distinction. + */ + for (; frame < ehci->periodic_size; frame += period) { + union ehci_shadow here; + __hc32 type; + struct ehci_qh_hw *hw; + + here = ehci->pshadow [frame]; + type = Q_NEXT_TYPE(ehci, ehci->periodic [frame]); + while (here.ptr) { + switch (hc32_to_cpu(ehci, type)) { + case Q_TYPE_ITD: + type = Q_NEXT_TYPE(ehci, here.itd->hw_next); + here = here.itd->itd_next; + continue; + case Q_TYPE_QH: + hw = here.qh->hw; + if (same_tt(dev, here.qh->ps.udev)) { + u32 mask; + + mask = hc32_to_cpu(ehci, + hw->hw_info2); + /* "knows" no gap is needed */ + mask |= mask >> 8; + if (mask & uf_mask) + break; + } + type = Q_NEXT_TYPE(ehci, hw->hw_next); + here = here.qh->qh_next; + continue; + case Q_TYPE_SITD: + if (same_tt (dev, here.sitd->urb->dev)) { + u16 mask; + + mask = hc32_to_cpu(ehci, here.sitd + ->hw_uframe); + /* FIXME assumes no gap for IN! */ + mask |= mask >> 8; + if (mask & uf_mask) + break; + } + type = Q_NEXT_TYPE(ehci, here.sitd->hw_next); + here = here.sitd->sitd_next; + continue; + // case Q_TYPE_FSTN: + default: + ehci_dbg (ehci, + "periodic frame %d bogus type %d\n", + frame, type); + } + + /* collision or error */ + return 0; + } + } + + /* no collision */ + return 1; +} + +#endif /* CONFIG_USB_EHCI_TT_NEWSCHED */ + +/*-------------------------------------------------------------------------*/ + +static void enable_periodic(struct ehci_hcd *ehci) +{ + if (ehci->periodic_count++) + return; + + /* Stop waiting to turn off the periodic schedule */ + ehci->enabled_hrtimer_events &= ~BIT(EHCI_HRTIMER_DISABLE_PERIODIC); + + /* Don't start the schedule until PSS is 0 */ + ehci_poll_PSS(ehci); + turn_on_io_watchdog(ehci); +} + +static void disable_periodic(struct ehci_hcd *ehci) +{ + if (--ehci->periodic_count) + return; + + /* Don't turn off the schedule until PSS is 1 */ + ehci_poll_PSS(ehci); +} + +/*-------------------------------------------------------------------------*/ + +/* periodic schedule slots have iso tds (normal or split) first, then a + * sparse tree for active interrupt transfers. + * + * this just links in a qh; caller guarantees uframe masks are set right. + * no FSTN support (yet; ehci 0.96+) + */ +static void qh_link_periodic(struct ehci_hcd *ehci, struct ehci_qh *qh) +{ + unsigned i; + unsigned period = qh->ps.period; + + dev_dbg(&qh->ps.udev->dev, + "link qh%d-%04x/%p start %d [%d/%d us]\n", + period, hc32_to_cpup(ehci, &qh->hw->hw_info2) + & (QH_CMASK | QH_SMASK), + qh, qh->ps.phase, qh->ps.usecs, qh->ps.c_usecs); + + /* high bandwidth, or otherwise every microframe */ + if (period == 0) + period = 1; + + for (i = qh->ps.phase; i < ehci->periodic_size; i += period) { + union ehci_shadow *prev = &ehci->pshadow[i]; + __hc32 *hw_p = &ehci->periodic[i]; + union ehci_shadow here = *prev; + __hc32 type = 0; + + /* skip the iso nodes at list head */ + while (here.ptr) { + type = Q_NEXT_TYPE(ehci, *hw_p); + if (type == cpu_to_hc32(ehci, Q_TYPE_QH)) + break; + prev = periodic_next_shadow(ehci, prev, type); + hw_p = shadow_next_periodic(ehci, &here, type); + here = *prev; + } + + /* sorting each branch by period (slow-->fast) + * enables sharing interior tree nodes + */ + while (here.ptr && qh != here.qh) { + if (qh->ps.period > here.qh->ps.period) + break; + prev = &here.qh->qh_next; + hw_p = &here.qh->hw->hw_next; + here = *prev; + } + /* link in this qh, unless some earlier pass did that */ + if (qh != here.qh) { + qh->qh_next = here; + if (here.qh) + qh->hw->hw_next = *hw_p; + wmb (); + prev->qh = qh; + *hw_p = QH_NEXT (ehci, qh->qh_dma); + } + } + qh->qh_state = QH_STATE_LINKED; + qh->xacterrs = 0; + qh->exception = 0; + + /* update per-qh bandwidth for debugfs */ + ehci_to_hcd(ehci)->self.bandwidth_allocated += qh->ps.bw_period + ? ((qh->ps.usecs + qh->ps.c_usecs) / qh->ps.bw_period) + : (qh->ps.usecs * 8); + + list_add(&qh->intr_node, &ehci->intr_qh_list); + + /* maybe enable periodic schedule processing */ + ++ehci->intr_count; + enable_periodic(ehci); +} + +static void qh_unlink_periodic(struct ehci_hcd *ehci, struct ehci_qh *qh) +{ + unsigned i; + unsigned period; + + /* + * If qh is for a low/full-speed device, simply unlinking it + * could interfere with an ongoing split transaction. To unlink + * it safely would require setting the QH_INACTIVATE bit and + * waiting at least one frame, as described in EHCI 4.12.2.5. + * + * We won't bother with any of this. Instead, we assume that the + * only reason for unlinking an interrupt QH while the current URB + * is still active is to dequeue all the URBs (flush the whole + * endpoint queue). + * + * If rebalancing the periodic schedule is ever implemented, this + * approach will no longer be valid. + */ + + /* high bandwidth, or otherwise part of every microframe */ + period = qh->ps.period ? : 1; + + for (i = qh->ps.phase; i < ehci->periodic_size; i += period) + periodic_unlink (ehci, i, qh); + + /* update per-qh bandwidth for debugfs */ + ehci_to_hcd(ehci)->self.bandwidth_allocated -= qh->ps.bw_period + ? ((qh->ps.usecs + qh->ps.c_usecs) / qh->ps.bw_period) + : (qh->ps.usecs * 8); + + dev_dbg(&qh->ps.udev->dev, + "unlink qh%d-%04x/%p start %d [%d/%d us]\n", + qh->ps.period, + hc32_to_cpup(ehci, &qh->hw->hw_info2) & (QH_CMASK | QH_SMASK), + qh, qh->ps.phase, qh->ps.usecs, qh->ps.c_usecs); + + /* qh->qh_next still "live" to HC */ + qh->qh_state = QH_STATE_UNLINK; + qh->qh_next.ptr = NULL; + + if (ehci->qh_scan_next == qh) + ehci->qh_scan_next = list_entry(qh->intr_node.next, + struct ehci_qh, intr_node); + list_del(&qh->intr_node); +} + +static void cancel_unlink_wait_intr(struct ehci_hcd *ehci, struct ehci_qh *qh) +{ + if (qh->qh_state != QH_STATE_LINKED || + list_empty(&qh->unlink_node)) + return; + + list_del_init(&qh->unlink_node); + + /* + * TODO: disable the event of EHCI_HRTIMER_START_UNLINK_INTR for + * avoiding unnecessary CPU wakeup + */ +} + +static void start_unlink_intr(struct ehci_hcd *ehci, struct ehci_qh *qh) +{ + /* If the QH isn't linked then there's nothing we can do. */ + if (qh->qh_state != QH_STATE_LINKED) + return; + + /* if the qh is waiting for unlink, cancel it now */ + cancel_unlink_wait_intr(ehci, qh); + + qh_unlink_periodic (ehci, qh); + + /* Make sure the unlinks are visible before starting the timer */ + wmb(); + + /* + * The EHCI spec doesn't say how long it takes the controller to + * stop accessing an unlinked interrupt QH. The timer delay is + * 9 uframes; presumably that will be long enough. + */ + qh->unlink_cycle = ehci->intr_unlink_cycle; + + /* New entries go at the end of the intr_unlink list */ + list_add_tail(&qh->unlink_node, &ehci->intr_unlink); + + if (ehci->intr_unlinking) + ; /* Avoid recursive calls */ + else if (ehci->rh_state < EHCI_RH_RUNNING) + ehci_handle_intr_unlinks(ehci); + else if (ehci->intr_unlink.next == &qh->unlink_node) { + ehci_enable_event(ehci, EHCI_HRTIMER_UNLINK_INTR, true); + ++ehci->intr_unlink_cycle; + } +} + +/* + * It is common only one intr URB is scheduled on one qh, and + * given complete() is run in tasklet context, introduce a bit + * delay to avoid unlink qh too early. + */ +static void start_unlink_intr_wait(struct ehci_hcd *ehci, + struct ehci_qh *qh) +{ + qh->unlink_cycle = ehci->intr_unlink_wait_cycle; + + /* New entries go at the end of the intr_unlink_wait list */ + list_add_tail(&qh->unlink_node, &ehci->intr_unlink_wait); + + if (ehci->rh_state < EHCI_RH_RUNNING) + ehci_handle_start_intr_unlinks(ehci); + else if (ehci->intr_unlink_wait.next == &qh->unlink_node) { + ehci_enable_event(ehci, EHCI_HRTIMER_START_UNLINK_INTR, true); + ++ehci->intr_unlink_wait_cycle; + } +} + +static void end_unlink_intr(struct ehci_hcd *ehci, struct ehci_qh *qh) +{ + struct ehci_qh_hw *hw = qh->hw; + int rc; + + qh->qh_state = QH_STATE_IDLE; + hw->hw_next = EHCI_LIST_END(ehci); + + if (!list_empty(&qh->qtd_list)) + qh_completions(ehci, qh); + + /* reschedule QH iff another request is queued */ + if (!list_empty(&qh->qtd_list) && ehci->rh_state == EHCI_RH_RUNNING) { + rc = qh_schedule(ehci, qh); + if (rc == 0) { + qh_refresh(ehci, qh); + qh_link_periodic(ehci, qh); + } + + /* An error here likely indicates handshake failure + * or no space left in the schedule. Neither fault + * should happen often ... + * + * FIXME kill the now-dysfunctional queued urbs + */ + else { + ehci_err(ehci, "can't reschedule qh %p, err %d\n", + qh, rc); + } + } + + /* maybe turn off periodic schedule */ + --ehci->intr_count; + disable_periodic(ehci); +} + +/*-------------------------------------------------------------------------*/ + +static int check_period ( + struct ehci_hcd *ehci, + unsigned frame, + unsigned uframe, + unsigned uperiod, + unsigned usecs +) { + /* complete split running into next frame? + * given FSTN support, we could sometimes check... + */ + if (uframe >= 8) + return 0; + + /* convert "usecs we need" to "max already claimed" */ + usecs = ehci->uframe_periodic_max - usecs; + + for (uframe += frame << 3; uframe < EHCI_BANDWIDTH_SIZE; + uframe += uperiod) { + if (ehci->bandwidth[uframe] > usecs) + return 0; + } + + // success! + return 1; +} + +static int check_intr_schedule ( + struct ehci_hcd *ehci, + unsigned frame, + unsigned uframe, + struct ehci_qh *qh, + unsigned *c_maskp, + struct ehci_tt *tt +) +{ + int retval = -ENOSPC; + u8 mask = 0; + + if (qh->ps.c_usecs && uframe >= 6) /* FSTN territory? */ + goto done; + + if (!check_period(ehci, frame, uframe, qh->ps.bw_uperiod, qh->ps.usecs)) + goto done; + if (!qh->ps.c_usecs) { + retval = 0; + *c_maskp = 0; + goto done; + } + +#ifdef CONFIG_USB_EHCI_TT_NEWSCHED + if (tt_available(ehci, &qh->ps, tt, frame, uframe)) { + unsigned i; + + /* TODO : this may need FSTN for SSPLIT in uframe 5. */ + for (i = uframe+2; i < 8 && i <= uframe+4; i++) + if (!check_period(ehci, frame, i, + qh->ps.bw_uperiod, qh->ps.c_usecs)) + goto done; + else + mask |= 1 << i; + + retval = 0; + + *c_maskp = mask; + } +#else + /* Make sure this tt's buffer is also available for CSPLITs. + * We pessimize a bit; probably the typical full speed case + * doesn't need the second CSPLIT. + * + * NOTE: both SPLIT and CSPLIT could be checked in just + * one smart pass... + */ + mask = 0x03 << (uframe + qh->gap_uf); + *c_maskp = mask; + + mask |= 1 << uframe; + if (tt_no_collision(ehci, qh->ps.bw_period, qh->ps.udev, frame, mask)) { + if (!check_period(ehci, frame, uframe + qh->gap_uf + 1, + qh->ps.bw_uperiod, qh->ps.c_usecs)) + goto done; + if (!check_period(ehci, frame, uframe + qh->gap_uf, + qh->ps.bw_uperiod, qh->ps.c_usecs)) + goto done; + retval = 0; + } +#endif +done: + return retval; +} + +/* "first fit" scheduling policy used the first time through, + * or when the previous schedule slot can't be re-used. + */ +static int qh_schedule(struct ehci_hcd *ehci, struct ehci_qh *qh) +{ + int status = 0; + unsigned uframe; + unsigned c_mask; + struct ehci_qh_hw *hw = qh->hw; + struct ehci_tt *tt; + + hw->hw_next = EHCI_LIST_END(ehci); + + /* reuse the previous schedule slots, if we can */ + if (qh->ps.phase != NO_FRAME) { + ehci_dbg(ehci, "reused qh %p schedule\n", qh); + return 0; + } + + uframe = 0; + c_mask = 0; + tt = find_tt(qh->ps.udev); + if (IS_ERR(tt)) { + status = PTR_ERR(tt); + goto done; + } + compute_tt_budget(ehci->tt_budget, tt); + + /* else scan the schedule to find a group of slots such that all + * uframes have enough periodic bandwidth available. + */ + /* "normal" case, uframing flexible except with splits */ + if (qh->ps.bw_period) { + int i; + unsigned frame; + + for (i = qh->ps.bw_period; i > 0; --i) { + frame = ++ehci->random_frame & (qh->ps.bw_period - 1); + for (uframe = 0; uframe < 8; uframe++) { + status = check_intr_schedule(ehci, + frame, uframe, qh, &c_mask, tt); + if (status == 0) + goto got_it; + } + } + + /* qh->ps.bw_period == 0 means every uframe */ + } else { + status = check_intr_schedule(ehci, 0, 0, qh, &c_mask, tt); + } + if (status) + goto done; + + got_it: + qh->ps.phase = (qh->ps.period ? ehci->random_frame & + (qh->ps.period - 1) : 0); + qh->ps.bw_phase = qh->ps.phase & (qh->ps.bw_period - 1); + qh->ps.phase_uf = uframe; + qh->ps.cs_mask = qh->ps.period ? + (c_mask << 8) | (1 << uframe) : + QH_SMASK; + + /* reset S-frame and (maybe) C-frame masks */ + hw->hw_info2 &= cpu_to_hc32(ehci, ~(QH_CMASK | QH_SMASK)); + hw->hw_info2 |= cpu_to_hc32(ehci, qh->ps.cs_mask); + reserve_release_intr_bandwidth(ehci, qh, 1); + +done: + return status; +} + +static int intr_submit ( + struct ehci_hcd *ehci, + struct urb *urb, + struct list_head *qtd_list, + gfp_t mem_flags +) { + unsigned epnum; + unsigned long flags; + struct ehci_qh *qh; + int status; + struct list_head empty; + + /* get endpoint and transfer/schedule data */ + epnum = urb->ep->desc.bEndpointAddress; + + spin_lock_irqsave (&ehci->lock, flags); + + if (unlikely(!HCD_HW_ACCESSIBLE(ehci_to_hcd(ehci)))) { + status = -ESHUTDOWN; + goto done_not_linked; + } + status = usb_hcd_link_urb_to_ep(ehci_to_hcd(ehci), urb); + if (unlikely(status)) + goto done_not_linked; + + /* get qh and force any scheduling errors */ + INIT_LIST_HEAD (&empty); + qh = qh_append_tds(ehci, urb, &empty, epnum, &urb->ep->hcpriv); + if (qh == NULL) { + status = -ENOMEM; + goto done; + } + if (qh->qh_state == QH_STATE_IDLE) { + if ((status = qh_schedule (ehci, qh)) != 0) + goto done; + } + + /* then queue the urb's tds to the qh */ + qh = qh_append_tds(ehci, urb, qtd_list, epnum, &urb->ep->hcpriv); + BUG_ON (qh == NULL); + + /* stuff into the periodic schedule */ + if (qh->qh_state == QH_STATE_IDLE) { + qh_refresh(ehci, qh); + qh_link_periodic(ehci, qh); + } else { + /* cancel unlink wait for the qh */ + cancel_unlink_wait_intr(ehci, qh); + } + + /* ... update usbfs periodic stats */ + ehci_to_hcd(ehci)->self.bandwidth_int_reqs++; + +done: + if (unlikely(status)) + usb_hcd_unlink_urb_from_ep(ehci_to_hcd(ehci), urb); +done_not_linked: + spin_unlock_irqrestore (&ehci->lock, flags); + if (status) + qtd_list_free (ehci, urb, qtd_list); + + return status; +} + +static void scan_intr(struct ehci_hcd *ehci) +{ + struct ehci_qh *qh; + + list_for_each_entry_safe(qh, ehci->qh_scan_next, &ehci->intr_qh_list, + intr_node) { + + /* clean any finished work for this qh */ + if (!list_empty(&qh->qtd_list)) { + int temp; + + /* + * Unlinks could happen here; completion reporting + * drops the lock. That's why ehci->qh_scan_next + * always holds the next qh to scan; if the next qh + * gets unlinked then ehci->qh_scan_next is adjusted + * in qh_unlink_periodic(). + */ + temp = qh_completions(ehci, qh); + if (unlikely(temp)) + start_unlink_intr(ehci, qh); + else if (unlikely(list_empty(&qh->qtd_list) && + qh->qh_state == QH_STATE_LINKED)) + start_unlink_intr_wait(ehci, qh); + } + } +} + +/*-------------------------------------------------------------------------*/ + +/* ehci_iso_stream ops work with both ITD and SITD */ + +static struct ehci_iso_stream * +iso_stream_alloc (gfp_t mem_flags) +{ + struct ehci_iso_stream *stream; + + stream = kzalloc(sizeof *stream, mem_flags); + if (likely (stream != NULL)) { + INIT_LIST_HEAD(&stream->td_list); + INIT_LIST_HEAD(&stream->free_list); + stream->next_uframe = NO_FRAME; + stream->ps.phase = NO_FRAME; + } + return stream; +} + +static void +iso_stream_init ( + struct ehci_hcd *ehci, + struct ehci_iso_stream *stream, + struct urb *urb +) +{ + static const u8 smask_out [] = { 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f }; + + struct usb_device *dev = urb->dev; + u32 buf1; + unsigned epnum, maxp; + int is_input; + unsigned tmp; + + /* + * this might be a "high bandwidth" highspeed endpoint, + * as encoded in the ep descriptor's wMaxPacket field + */ + epnum = usb_pipeendpoint(urb->pipe); + is_input = usb_pipein(urb->pipe) ? USB_DIR_IN : 0; + maxp = usb_endpoint_maxp(&urb->ep->desc); + if (is_input) { + buf1 = (1 << 11); + } else { + buf1 = 0; + } + + /* knows about ITD vs SITD */ + if (dev->speed == USB_SPEED_HIGH) { + unsigned multi = hb_mult(maxp); + + stream->highspeed = 1; + + maxp = max_packet(maxp); + buf1 |= maxp; + maxp *= multi; + + stream->buf0 = cpu_to_hc32(ehci, (epnum << 8) | dev->devnum); + stream->buf1 = cpu_to_hc32(ehci, buf1); + stream->buf2 = cpu_to_hc32(ehci, multi); + + /* usbfs wants to report the average usecs per frame tied up + * when transfers on this endpoint are scheduled ... + */ + stream->ps.usecs = HS_USECS_ISO(maxp); + + /* period for bandwidth allocation */ + tmp = min_t(unsigned, EHCI_BANDWIDTH_SIZE, + 1 << (urb->ep->desc.bInterval - 1)); + + /* Allow urb->interval to override */ + stream->ps.bw_uperiod = min_t(unsigned, tmp, urb->interval); + + stream->uperiod = urb->interval; + stream->ps.period = urb->interval >> 3; + stream->bandwidth = stream->ps.usecs * 8 / + stream->ps.bw_uperiod; + + } else { + u32 addr; + int think_time; + int hs_transfers; + + addr = dev->ttport << 24; + if (!ehci_is_TDI(ehci) + || (dev->tt->hub != + ehci_to_hcd(ehci)->self.root_hub)) + addr |= dev->tt->hub->devnum << 16; + addr |= epnum << 8; + addr |= dev->devnum; + stream->ps.usecs = HS_USECS_ISO(maxp); + think_time = dev->tt ? dev->tt->think_time : 0; + stream->ps.tt_usecs = NS_TO_US(think_time + usb_calc_bus_time( + dev->speed, is_input, 1, maxp)); + hs_transfers = max (1u, (maxp + 187) / 188); + if (is_input) { + u32 tmp; + + addr |= 1 << 31; + stream->ps.c_usecs = stream->ps.usecs; + stream->ps.usecs = HS_USECS_ISO(1); + stream->ps.cs_mask = 1; + + /* c-mask as specified in USB 2.0 11.18.4 3.c */ + tmp = (1 << (hs_transfers + 2)) - 1; + stream->ps.cs_mask |= tmp << (8 + 2); + } else + stream->ps.cs_mask = smask_out[hs_transfers - 1]; + + /* period for bandwidth allocation */ + tmp = min_t(unsigned, EHCI_BANDWIDTH_FRAMES, + 1 << (urb->ep->desc.bInterval - 1)); + + /* Allow urb->interval to override */ + stream->ps.bw_period = min_t(unsigned, tmp, urb->interval); + stream->ps.bw_uperiod = stream->ps.bw_period << 3; + + stream->ps.period = urb->interval; + stream->uperiod = urb->interval << 3; + stream->bandwidth = (stream->ps.usecs + stream->ps.c_usecs) / + stream->ps.bw_period; + + /* stream->splits gets created from cs_mask later */ + stream->address = cpu_to_hc32(ehci, addr); + } + + stream->ps.udev = dev; + stream->ps.ep = urb->ep; + + stream->bEndpointAddress = is_input | epnum; + stream->maxp = maxp; +} + +static struct ehci_iso_stream * +iso_stream_find (struct ehci_hcd *ehci, struct urb *urb) +{ + unsigned epnum; + struct ehci_iso_stream *stream; + struct usb_host_endpoint *ep; + unsigned long flags; + + epnum = usb_pipeendpoint (urb->pipe); + if (usb_pipein(urb->pipe)) + ep = urb->dev->ep_in[epnum]; + else + ep = urb->dev->ep_out[epnum]; + + spin_lock_irqsave (&ehci->lock, flags); + stream = ep->hcpriv; + + if (unlikely (stream == NULL)) { + stream = iso_stream_alloc(GFP_ATOMIC); + if (likely (stream != NULL)) { + ep->hcpriv = stream; + iso_stream_init(ehci, stream, urb); + } + + /* if dev->ep [epnum] is a QH, hw is set */ + } else if (unlikely (stream->hw != NULL)) { + ehci_dbg (ehci, "dev %s ep%d%s, not iso??\n", + urb->dev->devpath, epnum, + usb_pipein(urb->pipe) ? "in" : "out"); + stream = NULL; + } + + spin_unlock_irqrestore (&ehci->lock, flags); + return stream; +} + +/*-------------------------------------------------------------------------*/ + +/* ehci_iso_sched ops can be ITD-only or SITD-only */ + +static struct ehci_iso_sched * +iso_sched_alloc (unsigned packets, gfp_t mem_flags) +{ + struct ehci_iso_sched *iso_sched; + int size = sizeof *iso_sched; + + size += packets * sizeof (struct ehci_iso_packet); + iso_sched = kzalloc(size, mem_flags); + if (likely (iso_sched != NULL)) { + INIT_LIST_HEAD (&iso_sched->td_list); + } + return iso_sched; +} + +static inline void +itd_sched_init( + struct ehci_hcd *ehci, + struct ehci_iso_sched *iso_sched, + struct ehci_iso_stream *stream, + struct urb *urb +) +{ + unsigned i; + dma_addr_t dma = urb->transfer_dma; + + /* how many uframes are needed for these transfers */ + iso_sched->span = urb->number_of_packets * stream->uperiod; + + /* figure out per-uframe itd fields that we'll need later + * when we fit new itds into the schedule. + */ + for (i = 0; i < urb->number_of_packets; i++) { + struct ehci_iso_packet *uframe = &iso_sched->packet [i]; + unsigned length; + dma_addr_t buf; + u32 trans; + + length = urb->iso_frame_desc [i].length; + buf = dma + urb->iso_frame_desc [i].offset; + + trans = EHCI_ISOC_ACTIVE; + trans |= buf & 0x0fff; + if (unlikely (((i + 1) == urb->number_of_packets)) + && !(urb->transfer_flags & URB_NO_INTERRUPT)) + trans |= EHCI_ITD_IOC; + trans |= length << 16; + uframe->transaction = cpu_to_hc32(ehci, trans); + + /* might need to cross a buffer page within a uframe */ + uframe->bufp = (buf & ~(u64)0x0fff); + buf += length; + if (unlikely ((uframe->bufp != (buf & ~(u64)0x0fff)))) + uframe->cross = 1; + } +} + +static void +iso_sched_free ( + struct ehci_iso_stream *stream, + struct ehci_iso_sched *iso_sched +) +{ + if (!iso_sched) + return; + // caller must hold ehci->lock! + list_splice (&iso_sched->td_list, &stream->free_list); + kfree (iso_sched); +} + +static int +itd_urb_transaction ( + struct ehci_iso_stream *stream, + struct ehci_hcd *ehci, + struct urb *urb, + gfp_t mem_flags +) +{ + struct ehci_itd *itd; + dma_addr_t itd_dma; + int i; + unsigned num_itds; + struct ehci_iso_sched *sched; + unsigned long flags; + + sched = iso_sched_alloc (urb->number_of_packets, mem_flags); + if (unlikely (sched == NULL)) + return -ENOMEM; + + itd_sched_init(ehci, sched, stream, urb); + + if (urb->interval < 8) + num_itds = 1 + (sched->span + 7) / 8; + else + num_itds = urb->number_of_packets; + + /* allocate/init ITDs */ + spin_lock_irqsave (&ehci->lock, flags); + for (i = 0; i < num_itds; i++) { + + /* + * Use iTDs from the free list, but not iTDs that may + * still be in use by the hardware. + */ + if (likely(!list_empty(&stream->free_list))) { + itd = list_first_entry(&stream->free_list, + struct ehci_itd, itd_list); + if (itd->frame == ehci->now_frame) + goto alloc_itd; + list_del (&itd->itd_list); + itd_dma = itd->itd_dma; + } else { + alloc_itd: + spin_unlock_irqrestore (&ehci->lock, flags); + itd = dma_pool_alloc (ehci->itd_pool, mem_flags, + &itd_dma); + spin_lock_irqsave (&ehci->lock, flags); + if (!itd) { + iso_sched_free(stream, sched); + spin_unlock_irqrestore(&ehci->lock, flags); + return -ENOMEM; + } + } + + memset (itd, 0, sizeof *itd); + itd->itd_dma = itd_dma; + itd->frame = NO_FRAME; + list_add (&itd->itd_list, &sched->td_list); + } + spin_unlock_irqrestore (&ehci->lock, flags); + + /* temporarily store schedule info in hcpriv */ + urb->hcpriv = sched; + urb->error_count = 0; + return 0; +} + +/*-------------------------------------------------------------------------*/ + +static void reserve_release_iso_bandwidth(struct ehci_hcd *ehci, + struct ehci_iso_stream *stream, int sign) +{ + unsigned uframe; + unsigned i, j; + unsigned s_mask, c_mask, m; + int usecs = stream->ps.usecs; + int c_usecs = stream->ps.c_usecs; + int tt_usecs = stream->ps.tt_usecs; + struct ehci_tt *tt; + + if (stream->ps.phase == NO_FRAME) /* Bandwidth wasn't reserved */ + return; + uframe = stream->ps.bw_phase << 3; + + bandwidth_dbg(ehci, sign, "iso", &stream->ps); + + if (sign < 0) { /* Release bandwidth */ + usecs = -usecs; + c_usecs = -c_usecs; + tt_usecs = -tt_usecs; + } + + if (!stream->splits) { /* High speed */ + for (i = uframe + stream->ps.phase_uf; i < EHCI_BANDWIDTH_SIZE; + i += stream->ps.bw_uperiod) + ehci->bandwidth[i] += usecs; + + } else { /* Full speed */ + s_mask = stream->ps.cs_mask; + c_mask = s_mask >> 8; + + /* NOTE: adjustment needed for frame overflow */ + for (i = uframe; i < EHCI_BANDWIDTH_SIZE; + i += stream->ps.bw_uperiod) { + for ((j = stream->ps.phase_uf, m = 1 << j); j < 8; + (++j, m <<= 1)) { + if (s_mask & m) + ehci->bandwidth[i+j] += usecs; + else if (c_mask & m) + ehci->bandwidth[i+j] += c_usecs; + } + } + + tt = find_tt(stream->ps.udev); + if (sign > 0) + list_add_tail(&stream->ps.ps_list, &tt->ps_list); + else + list_del(&stream->ps.ps_list); + + for (i = uframe >> 3; i < EHCI_BANDWIDTH_FRAMES; + i += stream->ps.bw_period) + tt->bandwidth[i] += tt_usecs; + } +} + +static inline int +itd_slot_ok ( + struct ehci_hcd *ehci, + struct ehci_iso_stream *stream, + unsigned uframe +) +{ + unsigned usecs; + + /* convert "usecs we need" to "max already claimed" */ + usecs = ehci->uframe_periodic_max - stream->ps.usecs; + + for (uframe &= stream->ps.bw_uperiod - 1; uframe < EHCI_BANDWIDTH_SIZE; + uframe += stream->ps.bw_uperiod) { + if (ehci->bandwidth[uframe] > usecs) + return 0; + } + return 1; +} + +static inline int +sitd_slot_ok ( + struct ehci_hcd *ehci, + struct ehci_iso_stream *stream, + unsigned uframe, + struct ehci_iso_sched *sched, + struct ehci_tt *tt +) +{ + unsigned mask, tmp; + unsigned frame, uf; + + mask = stream->ps.cs_mask << (uframe & 7); + + /* for OUT, don't wrap SSPLIT into H-microframe 7 */ + if (((stream->ps.cs_mask & 0xff) << (uframe & 7)) >= (1 << 7)) + return 0; + + /* for IN, don't wrap CSPLIT into the next frame */ + if (mask & ~0xffff) + return 0; + + /* check bandwidth */ + uframe &= stream->ps.bw_uperiod - 1; + frame = uframe >> 3; + +#ifdef CONFIG_USB_EHCI_TT_NEWSCHED + /* The tt's fullspeed bus bandwidth must be available. + * tt_available scheduling guarantees 10+% for control/bulk. + */ + uf = uframe & 7; + if (!tt_available(ehci, &stream->ps, tt, frame, uf)) + return 0; +#else + /* tt must be idle for start(s), any gap, and csplit. + * assume scheduling slop leaves 10+% for control/bulk. + */ + if (!tt_no_collision(ehci, stream->ps.bw_period, + stream->ps.udev, frame, mask)) + return 0; +#endif + + do { + unsigned max_used; + unsigned i; + + /* check starts (OUT uses more than one) */ + uf = uframe; + max_used = ehci->uframe_periodic_max - stream->ps.usecs; + for (tmp = stream->ps.cs_mask & 0xff; tmp; tmp >>= 1, uf++) { + if (ehci->bandwidth[uf] > max_used) + return 0; + } + + /* for IN, check CSPLIT */ + if (stream->ps.c_usecs) { + max_used = ehci->uframe_periodic_max - + stream->ps.c_usecs; + uf = uframe & ~7; + tmp = 1 << (2+8); + for (i = (uframe & 7) + 2; i < 8; (++i, tmp <<= 1)) { + if ((stream->ps.cs_mask & tmp) == 0) + continue; + if (ehci->bandwidth[uf+i] > max_used) + return 0; + } + } + + uframe += stream->ps.bw_uperiod; + } while (uframe < EHCI_BANDWIDTH_SIZE); + + stream->ps.cs_mask <<= uframe & 7; + stream->splits = cpu_to_hc32(ehci, stream->ps.cs_mask); + return 1; +} + +/* + * This scheduler plans almost as far into the future as it has actual + * periodic schedule slots. (Affected by TUNE_FLS, which defaults to + * "as small as possible" to be cache-friendlier.) That limits the size + * transfers you can stream reliably; avoid more than 64 msec per urb. + * Also avoid queue depths of less than ehci's worst irq latency (affected + * by the per-urb URB_NO_INTERRUPT hint, the log2_irq_thresh module parameter, + * and other factors); or more than about 230 msec total (for portability, + * given EHCI_TUNE_FLS and the slop). Or, write a smarter scheduler! + */ + +static int +iso_stream_schedule ( + struct ehci_hcd *ehci, + struct urb *urb, + struct ehci_iso_stream *stream +) +{ + u32 now, base, next, start, period, span, now2; + u32 wrap = 0, skip = 0; + int status = 0; + unsigned mod = ehci->periodic_size << 3; + struct ehci_iso_sched *sched = urb->hcpriv; + bool empty = list_empty(&stream->td_list); + bool new_stream = false; + + period = stream->uperiod; + span = sched->span; + if (!stream->highspeed) + span <<= 3; + + /* Start a new isochronous stream? */ + if (unlikely(empty && !hcd_periodic_completion_in_progress( + ehci_to_hcd(ehci), urb->ep))) { + + /* Schedule the endpoint */ + if (stream->ps.phase == NO_FRAME) { + int done = 0; + struct ehci_tt *tt = find_tt(stream->ps.udev); + + if (IS_ERR(tt)) { + status = PTR_ERR(tt); + goto fail; + } + compute_tt_budget(ehci->tt_budget, tt); + + start = ((-(++ehci->random_frame)) << 3) & (period - 1); + + /* find a uframe slot with enough bandwidth. + * Early uframes are more precious because full-speed + * iso IN transfers can't use late uframes, + * and therefore they should be allocated last. + */ + next = start; + start += period; + do { + start--; + /* check schedule: enough space? */ + if (stream->highspeed) { + if (itd_slot_ok(ehci, stream, start)) + done = 1; + } else { + if ((start % 8) >= 6) + continue; + if (sitd_slot_ok(ehci, stream, start, + sched, tt)) + done = 1; + } + } while (start > next && !done); + + /* no room in the schedule */ + if (!done) { + ehci_dbg(ehci, "iso sched full %p", urb); + status = -ENOSPC; + goto fail; + } + stream->ps.phase = (start >> 3) & + (stream->ps.period - 1); + stream->ps.bw_phase = stream->ps.phase & + (stream->ps.bw_period - 1); + stream->ps.phase_uf = start & 7; + reserve_release_iso_bandwidth(ehci, stream, 1); + } + + /* New stream is already scheduled; use the upcoming slot */ + else { + start = (stream->ps.phase << 3) + stream->ps.phase_uf; + } + + stream->next_uframe = start; + new_stream = true; + } + + now = ehci_read_frame_index(ehci) & (mod - 1); + + /* Take the isochronous scheduling threshold into account */ + if (ehci->i_thresh) + next = now + ehci->i_thresh; /* uframe cache */ + else + next = (now + 2 + 7) & ~0x07; /* full frame cache */ + + /* If needed, initialize last_iso_frame so that this URB will be seen */ + if (ehci->isoc_count == 0) + ehci->last_iso_frame = now >> 3; + + /* + * Use ehci->last_iso_frame as the base. There can't be any + * TDs scheduled for earlier than that. + */ + base = ehci->last_iso_frame << 3; + next = (next - base) & (mod - 1); + start = (stream->next_uframe - base) & (mod - 1); + + if (unlikely(new_stream)) + goto do_ASAP; + + /* + * Typical case: reuse current schedule, stream may still be active. + * Hopefully there are no gaps from the host falling behind + * (irq delays etc). If there are, the behavior depends on + * whether URB_ISO_ASAP is set. + */ + now2 = (now - base) & (mod - 1); + + /* Is the schedule about to wrap around? */ + if (unlikely(!empty && start < period)) { + ehci_dbg(ehci, "request %p would overflow (%u-%u < %u mod %u)\n", + urb, stream->next_uframe, base, period, mod); + status = -EFBIG; + goto fail; + } + + /* Is the next packet scheduled after the base time? */ + if (likely(!empty || start <= now2 + period)) { + + /* URB_ISO_ASAP: make sure that start >= next */ + if (unlikely(start < next && + (urb->transfer_flags & URB_ISO_ASAP))) + goto do_ASAP; + + /* Otherwise use start, if it's not in the past */ + if (likely(start >= now2)) + goto use_start; + + /* Otherwise we got an underrun while the queue was empty */ + } else { + if (urb->transfer_flags & URB_ISO_ASAP) + goto do_ASAP; + wrap = mod; + now2 += mod; + } + + /* How many uframes and packets do we need to skip? */ + skip = (now2 - start + period - 1) & -period; + if (skip >= span) { /* Entirely in the past? */ + ehci_dbg(ehci, "iso underrun %p (%u+%u < %u) [%u]\n", + urb, start + base, span - period, now2 + base, + base); + + /* Try to keep the last TD intact for scanning later */ + skip = span - period; + + /* Will it come before the current scan position? */ + if (empty) { + skip = span; /* Skip the entire URB */ + status = 1; /* and give it back immediately */ + iso_sched_free(stream, sched); + sched = NULL; + } + } + urb->error_count = skip / period; + if (sched) + sched->first_packet = urb->error_count; + goto use_start; + + do_ASAP: + /* Use the first slot after "next" */ + start = next + ((start - next) & (period - 1)); + + use_start: + /* Tried to schedule too far into the future? */ + if (unlikely(start + span - period >= mod + wrap)) { + ehci_dbg(ehci, "request %p would overflow (%u+%u >= %u)\n", + urb, start, span - period, mod + wrap); + status = -EFBIG; + goto fail; + } + + start += base; + stream->next_uframe = (start + skip) & (mod - 1); + + /* report high speed start in uframes; full speed, in frames */ + urb->start_frame = start & (mod - 1); + if (!stream->highspeed) + urb->start_frame >>= 3; + return status; + + fail: + iso_sched_free(stream, sched); + urb->hcpriv = NULL; + return status; +} + +/*-------------------------------------------------------------------------*/ + +static inline void +itd_init(struct ehci_hcd *ehci, struct ehci_iso_stream *stream, + struct ehci_itd *itd) +{ + int i; + + /* it's been recently zeroed */ + itd->hw_next = EHCI_LIST_END(ehci); + itd->hw_bufp [0] = stream->buf0; + itd->hw_bufp [1] = stream->buf1; + itd->hw_bufp [2] = stream->buf2; + + for (i = 0; i < 8; i++) + itd->index[i] = -1; + + /* All other fields are filled when scheduling */ +} + +static inline void +itd_patch( + struct ehci_hcd *ehci, + struct ehci_itd *itd, + struct ehci_iso_sched *iso_sched, + unsigned index, + u16 uframe +) +{ + struct ehci_iso_packet *uf = &iso_sched->packet [index]; + unsigned pg = itd->pg; + + // BUG_ON (pg == 6 && uf->cross); + + uframe &= 0x07; + itd->index [uframe] = index; + + itd->hw_transaction[uframe] = uf->transaction; + itd->hw_transaction[uframe] |= cpu_to_hc32(ehci, pg << 12); + itd->hw_bufp[pg] |= cpu_to_hc32(ehci, uf->bufp & ~(u32)0); + itd->hw_bufp_hi[pg] |= cpu_to_hc32(ehci, (u32)(uf->bufp >> 32)); + + /* iso_frame_desc[].offset must be strictly increasing */ + if (unlikely (uf->cross)) { + u64 bufp = uf->bufp + 4096; + + itd->pg = ++pg; + itd->hw_bufp[pg] |= cpu_to_hc32(ehci, bufp & ~(u32)0); + itd->hw_bufp_hi[pg] |= cpu_to_hc32(ehci, (u32)(bufp >> 32)); + } +} + +static inline void +itd_link (struct ehci_hcd *ehci, unsigned frame, struct ehci_itd *itd) +{ + union ehci_shadow *prev = &ehci->pshadow[frame]; + __hc32 *hw_p = &ehci->periodic[frame]; + union ehci_shadow here = *prev; + __hc32 type = 0; + + /* skip any iso nodes which might belong to previous microframes */ + while (here.ptr) { + type = Q_NEXT_TYPE(ehci, *hw_p); + if (type == cpu_to_hc32(ehci, Q_TYPE_QH)) + break; + prev = periodic_next_shadow(ehci, prev, type); + hw_p = shadow_next_periodic(ehci, &here, type); + here = *prev; + } + + itd->itd_next = here; + itd->hw_next = *hw_p; + prev->itd = itd; + itd->frame = frame; + wmb (); + *hw_p = cpu_to_hc32(ehci, itd->itd_dma | Q_TYPE_ITD); +} + +/* fit urb's itds into the selected schedule slot; activate as needed */ +static void itd_link_urb( + struct ehci_hcd *ehci, + struct urb *urb, + unsigned mod, + struct ehci_iso_stream *stream +) +{ + int packet; + unsigned next_uframe, uframe, frame; + struct ehci_iso_sched *iso_sched = urb->hcpriv; + struct ehci_itd *itd; + + next_uframe = stream->next_uframe & (mod - 1); + + if (unlikely (list_empty(&stream->td_list))) + ehci_to_hcd(ehci)->self.bandwidth_allocated + += stream->bandwidth; + + if (ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs == 0) { + if (ehci->amd_pll_fix == 1) + usb_amd_quirk_pll_disable(); + } + + ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs++; + + /* fill iTDs uframe by uframe */ + for (packet = iso_sched->first_packet, itd = NULL; + packet < urb->number_of_packets;) { + if (itd == NULL) { + /* ASSERT: we have all necessary itds */ + // BUG_ON (list_empty (&iso_sched->td_list)); + + /* ASSERT: no itds for this endpoint in this uframe */ + + itd = list_entry (iso_sched->td_list.next, + struct ehci_itd, itd_list); + list_move_tail (&itd->itd_list, &stream->td_list); + itd->stream = stream; + itd->urb = urb; + itd_init (ehci, stream, itd); + } + + uframe = next_uframe & 0x07; + frame = next_uframe >> 3; + + itd_patch(ehci, itd, iso_sched, packet, uframe); + + next_uframe += stream->uperiod; + next_uframe &= mod - 1; + packet++; + + /* link completed itds into the schedule */ + if (((next_uframe >> 3) != frame) + || packet == urb->number_of_packets) { + itd_link(ehci, frame & (ehci->periodic_size - 1), itd); + itd = NULL; + } + } + stream->next_uframe = next_uframe; + + /* don't need that schedule data any more */ + iso_sched_free (stream, iso_sched); + urb->hcpriv = stream; + + ++ehci->isoc_count; + enable_periodic(ehci); +} + +#define ISO_ERRS (EHCI_ISOC_BUF_ERR | EHCI_ISOC_BABBLE | EHCI_ISOC_XACTERR) + +/* Process and recycle a completed ITD. Return true iff its urb completed, + * and hence its completion callback probably added things to the hardware + * schedule. + * + * Note that we carefully avoid recycling this descriptor until after any + * completion callback runs, so that it won't be reused quickly. That is, + * assuming (a) no more than two urbs per frame on this endpoint, and also + * (b) only this endpoint's completions submit URBs. It seems some silicon + * corrupts things if you reuse completed descriptors very quickly... + */ +static bool itd_complete(struct ehci_hcd *ehci, struct ehci_itd *itd) +{ + struct urb *urb = itd->urb; + struct usb_iso_packet_descriptor *desc; + u32 t; + unsigned uframe; + int urb_index = -1; + struct ehci_iso_stream *stream = itd->stream; + struct usb_device *dev; + bool retval = false; + + /* for each uframe with a packet */ + for (uframe = 0; uframe < 8; uframe++) { + if (likely (itd->index[uframe] == -1)) + continue; + urb_index = itd->index[uframe]; + desc = &urb->iso_frame_desc [urb_index]; + + t = hc32_to_cpup(ehci, &itd->hw_transaction [uframe]); + itd->hw_transaction [uframe] = 0; + + /* report transfer status */ + if (unlikely (t & ISO_ERRS)) { + urb->error_count++; + if (t & EHCI_ISOC_BUF_ERR) + desc->status = usb_pipein (urb->pipe) + ? -ENOSR /* hc couldn't read */ + : -ECOMM; /* hc couldn't write */ + else if (t & EHCI_ISOC_BABBLE) + desc->status = -EOVERFLOW; + else /* (t & EHCI_ISOC_XACTERR) */ + desc->status = -EPROTO; + + /* HC need not update length with this error */ + if (!(t & EHCI_ISOC_BABBLE)) { + desc->actual_length = EHCI_ITD_LENGTH(t); + urb->actual_length += desc->actual_length; + } + } else if (likely ((t & EHCI_ISOC_ACTIVE) == 0)) { + desc->status = 0; + desc->actual_length = EHCI_ITD_LENGTH(t); + urb->actual_length += desc->actual_length; + } else { + /* URB was too late */ + urb->error_count++; + } + } + + /* handle completion now? */ + if (likely ((urb_index + 1) != urb->number_of_packets)) + goto done; + + /* ASSERT: it's really the last itd for this urb + list_for_each_entry (itd, &stream->td_list, itd_list) + BUG_ON (itd->urb == urb); + */ + + /* give urb back to the driver; completion often (re)submits */ + dev = urb->dev; + ehci_urb_done(ehci, urb, 0); + retval = true; + urb = NULL; + + --ehci->isoc_count; + disable_periodic(ehci); + + ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs--; + if (ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs == 0) { + if (ehci->amd_pll_fix == 1) + usb_amd_quirk_pll_enable(); + } + + if (unlikely(list_is_singular(&stream->td_list))) + ehci_to_hcd(ehci)->self.bandwidth_allocated + -= stream->bandwidth; + +done: + itd->urb = NULL; + + /* Add to the end of the free list for later reuse */ + list_move_tail(&itd->itd_list, &stream->free_list); + + /* Recycle the iTDs when the pipeline is empty (ep no longer in use) */ + if (list_empty(&stream->td_list)) { + list_splice_tail_init(&stream->free_list, + &ehci->cached_itd_list); + start_free_itds(ehci); + } + + return retval; +} + +/*-------------------------------------------------------------------------*/ + +static int itd_submit (struct ehci_hcd *ehci, struct urb *urb, + gfp_t mem_flags) +{ + int status = -EINVAL; + unsigned long flags; + struct ehci_iso_stream *stream; + + /* Get iso_stream head */ + stream = iso_stream_find (ehci, urb); + if (unlikely (stream == NULL)) { + ehci_dbg (ehci, "can't get iso stream\n"); + return -ENOMEM; + } + if (unlikely(urb->interval != stream->uperiod)) { + ehci_dbg (ehci, "can't change iso interval %d --> %d\n", + stream->uperiod, urb->interval); + goto done; + } + +#ifdef EHCI_URB_TRACE + ehci_dbg (ehci, + "%s %s urb %p ep%d%s len %d, %d pkts %d uframes [%p]\n", + __func__, urb->dev->devpath, urb, + usb_pipeendpoint (urb->pipe), + usb_pipein (urb->pipe) ? "in" : "out", + urb->transfer_buffer_length, + urb->number_of_packets, urb->interval, + stream); +#endif + + /* allocate ITDs w/o locking anything */ + status = itd_urb_transaction (stream, ehci, urb, mem_flags); + if (unlikely (status < 0)) { + ehci_dbg (ehci, "can't init itds\n"); + goto done; + } + + /* schedule ... need to lock */ + spin_lock_irqsave (&ehci->lock, flags); + if (unlikely(!HCD_HW_ACCESSIBLE(ehci_to_hcd(ehci)))) { + status = -ESHUTDOWN; + goto done_not_linked; + } + status = usb_hcd_link_urb_to_ep(ehci_to_hcd(ehci), urb); + if (unlikely(status)) + goto done_not_linked; + status = iso_stream_schedule(ehci, urb, stream); + if (likely(status == 0)) { + itd_link_urb (ehci, urb, ehci->periodic_size << 3, stream); + } else if (status > 0) { + status = 0; + ehci_urb_done(ehci, urb, 0); + } else { + usb_hcd_unlink_urb_from_ep(ehci_to_hcd(ehci), urb); + } + done_not_linked: + spin_unlock_irqrestore (&ehci->lock, flags); + done: + return status; +} + +/*-------------------------------------------------------------------------*/ + +/* + * "Split ISO TDs" ... used for USB 1.1 devices going through the + * TTs in USB 2.0 hubs. These need microframe scheduling. + */ + +static inline void +sitd_sched_init( + struct ehci_hcd *ehci, + struct ehci_iso_sched *iso_sched, + struct ehci_iso_stream *stream, + struct urb *urb +) +{ + unsigned i; + dma_addr_t dma = urb->transfer_dma; + + /* how many frames are needed for these transfers */ + iso_sched->span = urb->number_of_packets * stream->ps.period; + + /* figure out per-frame sitd fields that we'll need later + * when we fit new sitds into the schedule. + */ + for (i = 0; i < urb->number_of_packets; i++) { + struct ehci_iso_packet *packet = &iso_sched->packet [i]; + unsigned length; + dma_addr_t buf; + u32 trans; + + length = urb->iso_frame_desc [i].length & 0x03ff; + buf = dma + urb->iso_frame_desc [i].offset; + + trans = SITD_STS_ACTIVE; + if (((i + 1) == urb->number_of_packets) + && !(urb->transfer_flags & URB_NO_INTERRUPT)) + trans |= SITD_IOC; + trans |= length << 16; + packet->transaction = cpu_to_hc32(ehci, trans); + + /* might need to cross a buffer page within a td */ + packet->bufp = buf; + packet->buf1 = (buf + length) & ~0x0fff; + if (packet->buf1 != (buf & ~(u64)0x0fff)) + packet->cross = 1; + + /* OUT uses multiple start-splits */ + if (stream->bEndpointAddress & USB_DIR_IN) + continue; + length = (length + 187) / 188; + if (length > 1) /* BEGIN vs ALL */ + length |= 1 << 3; + packet->buf1 |= length; + } +} + +static int +sitd_urb_transaction ( + struct ehci_iso_stream *stream, + struct ehci_hcd *ehci, + struct urb *urb, + gfp_t mem_flags +) +{ + struct ehci_sitd *sitd; + dma_addr_t sitd_dma; + int i; + struct ehci_iso_sched *iso_sched; + unsigned long flags; + + iso_sched = iso_sched_alloc (urb->number_of_packets, mem_flags); + if (iso_sched == NULL) + return -ENOMEM; + + sitd_sched_init(ehci, iso_sched, stream, urb); + + /* allocate/init sITDs */ + spin_lock_irqsave (&ehci->lock, flags); + for (i = 0; i < urb->number_of_packets; i++) { + + /* NOTE: for now, we don't try to handle wraparound cases + * for IN (using sitd->hw_backpointer, like a FSTN), which + * means we never need two sitds for full speed packets. + */ + + /* + * Use siTDs from the free list, but not siTDs that may + * still be in use by the hardware. + */ + if (likely(!list_empty(&stream->free_list))) { + sitd = list_first_entry(&stream->free_list, + struct ehci_sitd, sitd_list); + if (sitd->frame == ehci->now_frame) + goto alloc_sitd; + list_del (&sitd->sitd_list); + sitd_dma = sitd->sitd_dma; + } else { + alloc_sitd: + spin_unlock_irqrestore (&ehci->lock, flags); + sitd = dma_pool_alloc (ehci->sitd_pool, mem_flags, + &sitd_dma); + spin_lock_irqsave (&ehci->lock, flags); + if (!sitd) { + iso_sched_free(stream, iso_sched); + spin_unlock_irqrestore(&ehci->lock, flags); + return -ENOMEM; + } + } + + memset (sitd, 0, sizeof *sitd); + sitd->sitd_dma = sitd_dma; + sitd->frame = NO_FRAME; + list_add (&sitd->sitd_list, &iso_sched->td_list); + } + + /* temporarily store schedule info in hcpriv */ + urb->hcpriv = iso_sched; + urb->error_count = 0; + + spin_unlock_irqrestore (&ehci->lock, flags); + return 0; +} + +/*-------------------------------------------------------------------------*/ + +static inline void +sitd_patch( + struct ehci_hcd *ehci, + struct ehci_iso_stream *stream, + struct ehci_sitd *sitd, + struct ehci_iso_sched *iso_sched, + unsigned index +) +{ + struct ehci_iso_packet *uf = &iso_sched->packet [index]; + u64 bufp = uf->bufp; + + sitd->hw_next = EHCI_LIST_END(ehci); + sitd->hw_fullspeed_ep = stream->address; + sitd->hw_uframe = stream->splits; + sitd->hw_results = uf->transaction; + sitd->hw_backpointer = EHCI_LIST_END(ehci); + + bufp = uf->bufp; + sitd->hw_buf[0] = cpu_to_hc32(ehci, bufp); + sitd->hw_buf_hi[0] = cpu_to_hc32(ehci, bufp >> 32); + + sitd->hw_buf[1] = cpu_to_hc32(ehci, uf->buf1); + if (uf->cross) + bufp += 4096; + sitd->hw_buf_hi[1] = cpu_to_hc32(ehci, bufp >> 32); + sitd->index = index; +} + +static inline void +sitd_link (struct ehci_hcd *ehci, unsigned frame, struct ehci_sitd *sitd) +{ + /* note: sitd ordering could matter (CSPLIT then SSPLIT) */ + sitd->sitd_next = ehci->pshadow [frame]; + sitd->hw_next = ehci->periodic [frame]; + ehci->pshadow [frame].sitd = sitd; + sitd->frame = frame; + wmb (); + ehci->periodic[frame] = cpu_to_hc32(ehci, sitd->sitd_dma | Q_TYPE_SITD); +} + +/* fit urb's sitds into the selected schedule slot; activate as needed */ +static void sitd_link_urb( + struct ehci_hcd *ehci, + struct urb *urb, + unsigned mod, + struct ehci_iso_stream *stream +) +{ + int packet; + unsigned next_uframe; + struct ehci_iso_sched *sched = urb->hcpriv; + struct ehci_sitd *sitd; + + next_uframe = stream->next_uframe; + + if (list_empty(&stream->td_list)) + /* usbfs ignores TT bandwidth */ + ehci_to_hcd(ehci)->self.bandwidth_allocated + += stream->bandwidth; + + if (ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs == 0) { + if (ehci->amd_pll_fix == 1) + usb_amd_quirk_pll_disable(); + } + + ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs++; + + /* fill sITDs frame by frame */ + for (packet = sched->first_packet, sitd = NULL; + packet < urb->number_of_packets; + packet++) { + + /* ASSERT: we have all necessary sitds */ + BUG_ON (list_empty (&sched->td_list)); + + /* ASSERT: no itds for this endpoint in this frame */ + + sitd = list_entry (sched->td_list.next, + struct ehci_sitd, sitd_list); + list_move_tail (&sitd->sitd_list, &stream->td_list); + sitd->stream = stream; + sitd->urb = urb; + + sitd_patch(ehci, stream, sitd, sched, packet); + sitd_link(ehci, (next_uframe >> 3) & (ehci->periodic_size - 1), + sitd); + + next_uframe += stream->uperiod; + } + stream->next_uframe = next_uframe & (mod - 1); + + /* don't need that schedule data any more */ + iso_sched_free (stream, sched); + urb->hcpriv = stream; + + ++ehci->isoc_count; + enable_periodic(ehci); +} + +/*-------------------------------------------------------------------------*/ + +#define SITD_ERRS (SITD_STS_ERR | SITD_STS_DBE | SITD_STS_BABBLE \ + | SITD_STS_XACT | SITD_STS_MMF) + +/* Process and recycle a completed SITD. Return true iff its urb completed, + * and hence its completion callback probably added things to the hardware + * schedule. + * + * Note that we carefully avoid recycling this descriptor until after any + * completion callback runs, so that it won't be reused quickly. That is, + * assuming (a) no more than two urbs per frame on this endpoint, and also + * (b) only this endpoint's completions submit URBs. It seems some silicon + * corrupts things if you reuse completed descriptors very quickly... + */ +static bool sitd_complete(struct ehci_hcd *ehci, struct ehci_sitd *sitd) +{ + struct urb *urb = sitd->urb; + struct usb_iso_packet_descriptor *desc; + u32 t; + int urb_index = -1; + struct ehci_iso_stream *stream = sitd->stream; + struct usb_device *dev; + bool retval = false; + + urb_index = sitd->index; + desc = &urb->iso_frame_desc [urb_index]; + t = hc32_to_cpup(ehci, &sitd->hw_results); + + /* report transfer status */ + if (unlikely(t & SITD_ERRS)) { + urb->error_count++; + if (t & SITD_STS_DBE) + desc->status = usb_pipein (urb->pipe) + ? -ENOSR /* hc couldn't read */ + : -ECOMM; /* hc couldn't write */ + else if (t & SITD_STS_BABBLE) + desc->status = -EOVERFLOW; + else /* XACT, MMF, etc */ + desc->status = -EPROTO; + } else if (unlikely(t & SITD_STS_ACTIVE)) { + /* URB was too late */ + urb->error_count++; + } else { + desc->status = 0; + desc->actual_length = desc->length - SITD_LENGTH(t); + urb->actual_length += desc->actual_length; + } + + /* handle completion now? */ + if ((urb_index + 1) != urb->number_of_packets) + goto done; + + /* ASSERT: it's really the last sitd for this urb + list_for_each_entry (sitd, &stream->td_list, sitd_list) + BUG_ON (sitd->urb == urb); + */ + + /* give urb back to the driver; completion often (re)submits */ + dev = urb->dev; + ehci_urb_done(ehci, urb, 0); + retval = true; + urb = NULL; + + --ehci->isoc_count; + disable_periodic(ehci); + + ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs--; + if (ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs == 0) { + if (ehci->amd_pll_fix == 1) + usb_amd_quirk_pll_enable(); + } + + if (list_is_singular(&stream->td_list)) + ehci_to_hcd(ehci)->self.bandwidth_allocated + -= stream->bandwidth; + +done: + sitd->urb = NULL; + + /* Add to the end of the free list for later reuse */ + list_move_tail(&sitd->sitd_list, &stream->free_list); + + /* Recycle the siTDs when the pipeline is empty (ep no longer in use) */ + if (list_empty(&stream->td_list)) { + list_splice_tail_init(&stream->free_list, + &ehci->cached_sitd_list); + start_free_itds(ehci); + } + + return retval; +} + + +static int sitd_submit (struct ehci_hcd *ehci, struct urb *urb, + gfp_t mem_flags) +{ + int status = -EINVAL; + unsigned long flags; + struct ehci_iso_stream *stream; + + /* Get iso_stream head */ + stream = iso_stream_find (ehci, urb); + if (stream == NULL) { + ehci_dbg (ehci, "can't get iso stream\n"); + return -ENOMEM; + } + if (urb->interval != stream->ps.period) { + ehci_dbg (ehci, "can't change iso interval %d --> %d\n", + stream->ps.period, urb->interval); + goto done; + } + +#ifdef EHCI_URB_TRACE + ehci_dbg (ehci, + "submit %p dev%s ep%d%s-iso len %d\n", + urb, urb->dev->devpath, + usb_pipeendpoint (urb->pipe), + usb_pipein (urb->pipe) ? "in" : "out", + urb->transfer_buffer_length); +#endif + + /* allocate SITDs */ + status = sitd_urb_transaction (stream, ehci, urb, mem_flags); + if (status < 0) { + ehci_dbg (ehci, "can't init sitds\n"); + goto done; + } + + /* schedule ... need to lock */ + spin_lock_irqsave (&ehci->lock, flags); + if (unlikely(!HCD_HW_ACCESSIBLE(ehci_to_hcd(ehci)))) { + status = -ESHUTDOWN; + goto done_not_linked; + } + status = usb_hcd_link_urb_to_ep(ehci_to_hcd(ehci), urb); + if (unlikely(status)) + goto done_not_linked; + status = iso_stream_schedule(ehci, urb, stream); + if (likely(status == 0)) { + sitd_link_urb (ehci, urb, ehci->periodic_size << 3, stream); + } else if (status > 0) { + status = 0; + ehci_urb_done(ehci, urb, 0); + } else { + usb_hcd_unlink_urb_from_ep(ehci_to_hcd(ehci), urb); + } + done_not_linked: + spin_unlock_irqrestore (&ehci->lock, flags); + done: + return status; +} + +/*-------------------------------------------------------------------------*/ + +static void scan_isoc(struct ehci_hcd *ehci) +{ + unsigned uf, now_frame, frame; + unsigned fmask = ehci->periodic_size - 1; + bool modified, live; + + /* + * When running, scan from last scan point up to "now" + * else clean up by scanning everything that's left. + * Touches as few pages as possible: cache-friendly. + */ + if (ehci->rh_state >= EHCI_RH_RUNNING) { + uf = ehci_read_frame_index(ehci); + now_frame = (uf >> 3) & fmask; + live = true; + } else { + now_frame = (ehci->last_iso_frame - 1) & fmask; + live = false; + } + ehci->now_frame = now_frame; + + frame = ehci->last_iso_frame; + for (;;) { + union ehci_shadow q, *q_p; + __hc32 type, *hw_p; + +restart: + /* scan each element in frame's queue for completions */ + q_p = &ehci->pshadow [frame]; + hw_p = &ehci->periodic [frame]; + q.ptr = q_p->ptr; + type = Q_NEXT_TYPE(ehci, *hw_p); + modified = false; + + while (q.ptr != NULL) { + switch (hc32_to_cpu(ehci, type)) { + case Q_TYPE_ITD: + /* If this ITD is still active, leave it for + * later processing ... check the next entry. + * No need to check for activity unless the + * frame is current. + */ + if (frame == now_frame && live) { + rmb(); + for (uf = 0; uf < 8; uf++) { + if (q.itd->hw_transaction[uf] & + ITD_ACTIVE(ehci)) + break; + } + if (uf < 8) { + q_p = &q.itd->itd_next; + hw_p = &q.itd->hw_next; + type = Q_NEXT_TYPE(ehci, + q.itd->hw_next); + q = *q_p; + break; + } + } + + /* Take finished ITDs out of the schedule + * and process them: recycle, maybe report + * URB completion. HC won't cache the + * pointer for much longer, if at all. + */ + *q_p = q.itd->itd_next; + if (!ehci->use_dummy_qh || + q.itd->hw_next != EHCI_LIST_END(ehci)) + *hw_p = q.itd->hw_next; + else + *hw_p = cpu_to_hc32(ehci, + ehci->dummy->qh_dma); + type = Q_NEXT_TYPE(ehci, q.itd->hw_next); + wmb(); + modified = itd_complete (ehci, q.itd); + q = *q_p; + break; + case Q_TYPE_SITD: + /* If this SITD is still active, leave it for + * later processing ... check the next entry. + * No need to check for activity unless the + * frame is current. + */ + if (((frame == now_frame) || + (((frame + 1) & fmask) == now_frame)) + && live + && (q.sitd->hw_results & + SITD_ACTIVE(ehci))) { + + q_p = &q.sitd->sitd_next; + hw_p = &q.sitd->hw_next; + type = Q_NEXT_TYPE(ehci, + q.sitd->hw_next); + q = *q_p; + break; + } + + /* Take finished SITDs out of the schedule + * and process them: recycle, maybe report + * URB completion. + */ + *q_p = q.sitd->sitd_next; + if (!ehci->use_dummy_qh || + q.sitd->hw_next != EHCI_LIST_END(ehci)) + *hw_p = q.sitd->hw_next; + else + *hw_p = cpu_to_hc32(ehci, + ehci->dummy->qh_dma); + type = Q_NEXT_TYPE(ehci, q.sitd->hw_next); + wmb(); + modified = sitd_complete (ehci, q.sitd); + q = *q_p; + break; + default: + ehci_dbg(ehci, "corrupt type %d frame %d shadow %p\n", + type, frame, q.ptr); + // BUG (); + /* FALL THROUGH */ + case Q_TYPE_QH: + case Q_TYPE_FSTN: + /* End of the iTDs and siTDs */ + q.ptr = NULL; + break; + } + + /* assume completion callbacks modify the queue */ + if (unlikely(modified && ehci->isoc_count > 0)) + goto restart; + } + + /* Stop when we have reached the current frame */ + if (frame == now_frame) + break; + + /* The last frame may still have active siTDs */ + ehci->last_iso_frame = frame; + frame = (frame + 1) & fmask; + } +} |