summaryrefslogtreecommitdiffstats
path: root/drivers/usb/host/ehci-sched.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/usb/host/ehci-sched.c')
-rw-r--r--drivers/usb/host/ehci-sched.c2500
1 files changed, 2500 insertions, 0 deletions
diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c
new file mode 100644
index 000000000..da7b00a61
--- /dev/null
+++ b/drivers/usb/host/ehci-sched.c
@@ -0,0 +1,2500 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2001-2004 by David Brownell
+ * Copyright (c) 2003 Michal Sojka, for high-speed iso transfers
+ */
+
+/* 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 = kcalloc(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;
+ }
+ 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 = hc32_to_cpu(ehci, mask) & QH_SMASK;
+
+ 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 (usecs > 125) {
+ int ufs = (usecs / 125);
+
+ for (i = uframe; i < (uframe + ufs) && i < 8; i++)
+ if (tt_usecs[i] > 0)
+ 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->unlink_reason = 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) {
+ status = qh_schedule(ehci, qh);
+ if (status)
+ 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);
+ buf1 = is_input ? 1 << 11 : 0;
+
+ /* knows about ITD vs SITD */
+ if (dev->speed == USB_SPEED_HIGH) {
+ unsigned multi = usb_endpoint_maxp_mult(&urb->ep->desc);
+
+ stream->highspeed = 1;
+
+ 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->think_time;
+ 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;
+ 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 */
+ 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;
+
+ 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;
+ struct ehci_iso_stream *stream = sitd->stream;
+ 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 */
+ 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;
+ union ehci_shadow q, *q_p;
+ __hc32 type, *hw_p;
+
+ /*
+ * 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;
+
+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)
+ return;
+
+ /* The last frame may still have active siTDs */
+ ehci->last_iso_frame = frame;
+ frame = (frame + 1) & fmask;
+
+ goto restart;
+}