diff options
Diffstat (limited to 'drivers/usb/host/ohci-q.c')
| -rw-r--r-- | drivers/usb/host/ohci-q.c | 1107 |
1 files changed, 1107 insertions, 0 deletions
diff --git a/drivers/usb/host/ohci-q.c b/drivers/usb/host/ohci-q.c new file mode 100644 index 000000000000..c90114a77277 --- /dev/null +++ b/drivers/usb/host/ohci-q.c @@ -0,0 +1,1107 @@ +/* + * OHCI HCD (Host Controller Driver) for USB. + * + * (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at> + * (C) Copyright 2000-2002 David Brownell <dbrownell@users.sourceforge.net> + * + * This file is licenced under the GPL. + */ + +static void urb_free_priv (struct ohci_hcd *hc, urb_priv_t *urb_priv) +{ + int last = urb_priv->length - 1; + + if (last >= 0) { + int i; + struct td *td; + + for (i = 0; i <= last; i++) { + td = urb_priv->td [i]; + if (td) + td_free (hc, td); + } + } + + list_del (&urb_priv->pending); + kfree (urb_priv); +} + +/*-------------------------------------------------------------------------*/ + +/* + * URB goes back to driver, and isn't reissued. + * It's completely gone from HC data structures. + * PRECONDITION: ohci lock held, irqs blocked. + */ +static void +finish_urb (struct ohci_hcd *ohci, struct urb *urb, struct pt_regs *regs) +__releases(ohci->lock) +__acquires(ohci->lock) +{ + // ASSERT (urb->hcpriv != 0); + + urb_free_priv (ohci, urb->hcpriv); + urb->hcpriv = NULL; + + spin_lock (&urb->lock); + if (likely (urb->status == -EINPROGRESS)) + urb->status = 0; + /* report short control reads right even though the data TD always + * has TD_R set. (much simpler, but creates the 1-td limit.) + */ + if (unlikely (urb->transfer_flags & URB_SHORT_NOT_OK) + && unlikely (usb_pipecontrol (urb->pipe)) + && urb->actual_length < urb->transfer_buffer_length + && usb_pipein (urb->pipe) + && urb->status == 0) { + urb->status = -EREMOTEIO; + } + spin_unlock (&urb->lock); + + switch (usb_pipetype (urb->pipe)) { + case PIPE_ISOCHRONOUS: + ohci_to_hcd(ohci)->self.bandwidth_isoc_reqs--; + break; + case PIPE_INTERRUPT: + ohci_to_hcd(ohci)->self.bandwidth_int_reqs--; + break; + } + +#ifdef OHCI_VERBOSE_DEBUG + urb_print (urb, "RET", usb_pipeout (urb->pipe)); +#endif + + /* urb->complete() can reenter this HCD */ + spin_unlock (&ohci->lock); + usb_hcd_giveback_urb (ohci_to_hcd(ohci), urb, regs); + spin_lock (&ohci->lock); + + /* stop periodic dma if it's not needed */ + if (ohci_to_hcd(ohci)->self.bandwidth_isoc_reqs == 0 + && ohci_to_hcd(ohci)->self.bandwidth_int_reqs == 0) { + ohci->hc_control &= ~(OHCI_CTRL_PLE|OHCI_CTRL_IE); + ohci_writel (ohci, ohci->hc_control, &ohci->regs->control); + } +} + + +/*-------------------------------------------------------------------------* + * ED handling functions + *-------------------------------------------------------------------------*/ + +/* search for the right schedule branch to use for a periodic ed. + * does some load balancing; returns the branch, or negative errno. + */ +static int balance (struct ohci_hcd *ohci, int interval, int load) +{ + int i, branch = -ENOSPC; + + /* iso periods can be huge; iso tds specify frame numbers */ + if (interval > NUM_INTS) + interval = NUM_INTS; + + /* search for the least loaded schedule branch of that period + * that has enough bandwidth left unreserved. + */ + for (i = 0; i < interval ; i++) { + if (branch < 0 || ohci->load [branch] > ohci->load [i]) { +#if 1 /* CONFIG_USB_BANDWIDTH */ + int j; + + /* usb 1.1 says 90% of one frame */ + for (j = i; j < NUM_INTS; j += interval) { + if ((ohci->load [j] + load) > 900) + break; + } + if (j < NUM_INTS) + continue; +#endif + branch = i; + } + } + return branch; +} + +/*-------------------------------------------------------------------------*/ + +/* both iso and interrupt requests have periods; this routine puts them + * into the schedule tree in the apppropriate place. most iso devices use + * 1msec periods, but that's not required. + */ +static void periodic_link (struct ohci_hcd *ohci, struct ed *ed) +{ + unsigned i; + + ohci_vdbg (ohci, "link %sed %p branch %d [%dus.], interval %d\n", + (ed->hwINFO & cpu_to_hc32 (ohci, ED_ISO)) ? "iso " : "", + ed, ed->branch, ed->load, ed->interval); + + for (i = ed->branch; i < NUM_INTS; i += ed->interval) { + struct ed **prev = &ohci->periodic [i]; + __hc32 *prev_p = &ohci->hcca->int_table [i]; + struct ed *here = *prev; + + /* sorting each branch by period (slow before fast) + * lets us share the faster parts of the tree. + * (plus maybe: put interrupt eds before iso) + */ + while (here && ed != here) { + if (ed->interval > here->interval) + break; + prev = &here->ed_next; + prev_p = &here->hwNextED; + here = *prev; + } + if (ed != here) { + ed->ed_next = here; + if (here) + ed->hwNextED = *prev_p; + wmb (); + *prev = ed; + *prev_p = cpu_to_hc32(ohci, ed->dma); + wmb(); + } + ohci->load [i] += ed->load; + } + ohci_to_hcd(ohci)->self.bandwidth_allocated += ed->load / ed->interval; +} + +/* link an ed into one of the HC chains */ + +static int ed_schedule (struct ohci_hcd *ohci, struct ed *ed) +{ + int branch; + + if (ohci_to_hcd(ohci)->state == HC_STATE_QUIESCING) + return -EAGAIN; + + ed->state = ED_OPER; + ed->ed_prev = NULL; + ed->ed_next = NULL; + ed->hwNextED = 0; + wmb (); + + /* we care about rm_list when setting CLE/BLE in case the HC was at + * work on some TD when CLE/BLE was turned off, and isn't quiesced + * yet. finish_unlinks() restarts as needed, some upcoming INTR_SF. + * + * control and bulk EDs are doubly linked (ed_next, ed_prev), but + * periodic ones are singly linked (ed_next). that's because the + * periodic schedule encodes a tree like figure 3-5 in the ohci + * spec: each qh can have several "previous" nodes, and the tree + * doesn't have unused/idle descriptors. + */ + switch (ed->type) { + case PIPE_CONTROL: + if (ohci->ed_controltail == NULL) { + WARN_ON (ohci->hc_control & OHCI_CTRL_CLE); + ohci_writel (ohci, ed->dma, + &ohci->regs->ed_controlhead); + } else { + ohci->ed_controltail->ed_next = ed; + ohci->ed_controltail->hwNextED = cpu_to_hc32 (ohci, + ed->dma); + } + ed->ed_prev = ohci->ed_controltail; + if (!ohci->ed_controltail && !ohci->ed_rm_list) { + wmb(); + ohci->hc_control |= OHCI_CTRL_CLE; + ohci_writel (ohci, 0, &ohci->regs->ed_controlcurrent); + ohci_writel (ohci, ohci->hc_control, + &ohci->regs->control); + } + ohci->ed_controltail = ed; + break; + + case PIPE_BULK: + if (ohci->ed_bulktail == NULL) { + WARN_ON (ohci->hc_control & OHCI_CTRL_BLE); + ohci_writel (ohci, ed->dma, &ohci->regs->ed_bulkhead); + } else { + ohci->ed_bulktail->ed_next = ed; + ohci->ed_bulktail->hwNextED = cpu_to_hc32 (ohci, + ed->dma); + } + ed->ed_prev = ohci->ed_bulktail; + if (!ohci->ed_bulktail && !ohci->ed_rm_list) { + wmb(); + ohci->hc_control |= OHCI_CTRL_BLE; + ohci_writel (ohci, 0, &ohci->regs->ed_bulkcurrent); + ohci_writel (ohci, ohci->hc_control, + &ohci->regs->control); + } + ohci->ed_bulktail = ed; + break; + + // case PIPE_INTERRUPT: + // case PIPE_ISOCHRONOUS: + default: + branch = balance (ohci, ed->interval, ed->load); + if (branch < 0) { + ohci_dbg (ohci, + "ERR %d, interval %d msecs, load %d\n", + branch, ed->interval, ed->load); + // FIXME if there are TDs queued, fail them! + return branch; + } + ed->branch = branch; + periodic_link (ohci, ed); + } + + /* the HC may not see the schedule updates yet, but if it does + * then they'll be properly ordered. + */ + return 0; +} + +/*-------------------------------------------------------------------------*/ + +/* scan the periodic table to find and unlink this ED */ +static void periodic_unlink (struct ohci_hcd *ohci, struct ed *ed) +{ + int i; + + for (i = ed->branch; i < NUM_INTS; i += ed->interval) { + struct ed *temp; + struct ed **prev = &ohci->periodic [i]; + __hc32 *prev_p = &ohci->hcca->int_table [i]; + + while (*prev && (temp = *prev) != ed) { + prev_p = &temp->hwNextED; + prev = &temp->ed_next; + } + if (*prev) { + *prev_p = ed->hwNextED; + *prev = ed->ed_next; + } + ohci->load [i] -= ed->load; + } + ohci_to_hcd(ohci)->self.bandwidth_allocated -= ed->load / ed->interval; + + ohci_vdbg (ohci, "unlink %sed %p branch %d [%dus.], interval %d\n", + (ed->hwINFO & cpu_to_hc32 (ohci, ED_ISO)) ? "iso " : "", + ed, ed->branch, ed->load, ed->interval); +} + +/* unlink an ed from one of the HC chains. + * just the link to the ed is unlinked. + * the link from the ed still points to another operational ed or 0 + * so the HC can eventually finish the processing of the unlinked ed + * (assuming it already started that, which needn't be true). + * + * ED_UNLINK is a transient state: the HC may still see this ED, but soon + * it won't. ED_SKIP means the HC will finish its current transaction, + * but won't start anything new. The TD queue may still grow; device + * drivers don't know about this HCD-internal state. + * + * When the HC can't see the ED, something changes ED_UNLINK to one of: + * + * - ED_OPER: when there's any request queued, the ED gets rescheduled + * immediately. HC should be working on them. + * + * - ED_IDLE: when there's no TD queue. there's no reason for the HC + * to care about this ED; safe to disable the endpoint. + * + * When finish_unlinks() runs later, after SOF interrupt, it will often + * complete one or more URB unlinks before making that state change. + */ +static void ed_deschedule (struct ohci_hcd *ohci, struct ed *ed) +{ + ed->hwINFO |= cpu_to_hc32 (ohci, ED_SKIP); + wmb (); + ed->state = ED_UNLINK; + + /* To deschedule something from the control or bulk list, just + * clear CLE/BLE and wait. There's no safe way to scrub out list + * head/current registers until later, and "later" isn't very + * tightly specified. Figure 6-5 and Section 6.4.2.2 show how + * the HC is reading the ED queues (while we modify them). + * + * For now, ed_schedule() is "later". It might be good paranoia + * to scrub those registers in finish_unlinks(), in case of bugs + * that make the HC try to use them. + */ + switch (ed->type) { + case PIPE_CONTROL: + /* remove ED from the HC's list: */ + if (ed->ed_prev == NULL) { + if (!ed->hwNextED) { + ohci->hc_control &= ~OHCI_CTRL_CLE; + ohci_writel (ohci, ohci->hc_control, + &ohci->regs->control); + // a ohci_readl() later syncs CLE with the HC + } else + ohci_writel (ohci, + hc32_to_cpup (ohci, &ed->hwNextED), + &ohci->regs->ed_controlhead); + } else { + ed->ed_prev->ed_next = ed->ed_next; + ed->ed_prev->hwNextED = ed->hwNextED; + } + /* remove ED from the HCD's list: */ + if (ohci->ed_controltail == ed) { + ohci->ed_controltail = ed->ed_prev; + if (ohci->ed_controltail) + ohci->ed_controltail->ed_next = NULL; + } else if (ed->ed_next) { + ed->ed_next->ed_prev = ed->ed_prev; + } + break; + + case PIPE_BULK: + /* remove ED from the HC's list: */ + if (ed->ed_prev == NULL) { + if (!ed->hwNextED) { + ohci->hc_control &= ~OHCI_CTRL_BLE; + ohci_writel (ohci, ohci->hc_control, + &ohci->regs->control); + // a ohci_readl() later syncs BLE with the HC + } else + ohci_writel (ohci, + hc32_to_cpup (ohci, &ed->hwNextED), + &ohci->regs->ed_bulkhead); + } else { + ed->ed_prev->ed_next = ed->ed_next; + ed->ed_prev->hwNextED = ed->hwNextED; + } + /* remove ED from the HCD's list: */ + if (ohci->ed_bulktail == ed) { + ohci->ed_bulktail = ed->ed_prev; + if (ohci->ed_bulktail) + ohci->ed_bulktail->ed_next = NULL; + } else if (ed->ed_next) { + ed->ed_next->ed_prev = ed->ed_prev; + } + break; + + // case PIPE_INTERRUPT: + // case PIPE_ISOCHRONOUS: + default: + periodic_unlink (ohci, ed); + break; + } +} + + +/*-------------------------------------------------------------------------*/ + +/* get and maybe (re)init an endpoint. init _should_ be done only as part + * of enumeration, usb_set_configuration() or usb_set_interface(). + */ +static struct ed *ed_get ( + struct ohci_hcd *ohci, + struct usb_host_endpoint *ep, + struct usb_device *udev, + unsigned int pipe, + int interval +) { + struct ed *ed; + unsigned long flags; + + spin_lock_irqsave (&ohci->lock, flags); + + if (!(ed = ep->hcpriv)) { + struct td *td; + int is_out; + u32 info; + + ed = ed_alloc (ohci, GFP_ATOMIC); + if (!ed) { + /* out of memory */ + goto done; + } + + /* dummy td; end of td list for ed */ + td = td_alloc (ohci, GFP_ATOMIC); + if (!td) { + /* out of memory */ + ed_free (ohci, ed); + ed = NULL; + goto done; + } + ed->dummy = td; + ed->hwTailP = cpu_to_hc32 (ohci, td->td_dma); + ed->hwHeadP = ed->hwTailP; /* ED_C, ED_H zeroed */ + ed->state = ED_IDLE; + + is_out = !(ep->desc.bEndpointAddress & USB_DIR_IN); + + /* FIXME usbcore changes dev->devnum before SET_ADDRESS + * suceeds ... otherwise we wouldn't need "pipe". + */ + info = usb_pipedevice (pipe); + ed->type = usb_pipetype(pipe); + + info |= (ep->desc.bEndpointAddress & ~USB_DIR_IN) << 7; + info |= le16_to_cpu(ep->desc.wMaxPacketSize) << 16; + if (udev->speed == USB_SPEED_LOW) + info |= ED_LOWSPEED; + /* only control transfers store pids in tds */ + if (ed->type != PIPE_CONTROL) { + info |= is_out ? ED_OUT : ED_IN; + if (ed->type != PIPE_BULK) { + /* periodic transfers... */ + if (ed->type == PIPE_ISOCHRONOUS) + info |= ED_ISO; + else if (interval > 32) /* iso can be bigger */ + interval = 32; + ed->interval = interval; + ed->load = usb_calc_bus_time ( + udev->speed, !is_out, + ed->type == PIPE_ISOCHRONOUS, + le16_to_cpu(ep->desc.wMaxPacketSize)) + / 1000; + } + } + ed->hwINFO = cpu_to_hc32(ohci, info); + + ep->hcpriv = ed; + } + +done: + spin_unlock_irqrestore (&ohci->lock, flags); + return ed; +} + +/*-------------------------------------------------------------------------*/ + +/* request unlinking of an endpoint from an operational HC. + * put the ep on the rm_list + * real work is done at the next start frame (SF) hardware interrupt + * caller guarantees HCD is running, so hardware access is safe, + * and that ed->state is ED_OPER + */ +static void start_ed_unlink (struct ohci_hcd *ohci, struct ed *ed) +{ + ed->hwINFO |= cpu_to_hc32 (ohci, ED_DEQUEUE); + ed_deschedule (ohci, ed); + + /* rm_list is just singly linked, for simplicity */ + ed->ed_next = ohci->ed_rm_list; + ed->ed_prev = NULL; + ohci->ed_rm_list = ed; + + /* enable SOF interrupt */ + ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrstatus); + ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrenable); + // flush those writes, and get latest HCCA contents + (void) ohci_readl (ohci, &ohci->regs->control); + + /* SF interrupt might get delayed; record the frame counter value that + * indicates when the HC isn't looking at it, so concurrent unlinks + * behave. frame_no wraps every 2^16 msec, and changes right before + * SF is triggered. + */ + ed->tick = ohci_frame_no(ohci) + 1; + +} + +/*-------------------------------------------------------------------------* + * TD handling functions + *-------------------------------------------------------------------------*/ + +/* enqueue next TD for this URB (OHCI spec 5.2.8.2) */ + +static void +td_fill (struct ohci_hcd *ohci, u32 info, + dma_addr_t data, int len, + struct urb *urb, int index) +{ + struct td *td, *td_pt; + struct urb_priv *urb_priv = urb->hcpriv; + int is_iso = info & TD_ISO; + int hash; + + // ASSERT (index < urb_priv->length); + + /* aim for only one interrupt per urb. mostly applies to control + * and iso; other urbs rarely need more than one TD per urb. + * this way, only final tds (or ones with an error) cause IRQs. + * at least immediately; use DI=6 in case any control request is + * tempted to die part way through. (and to force the hc to flush + * its donelist soonish, even on unlink paths.) + * + * NOTE: could delay interrupts even for the last TD, and get fewer + * interrupts ... increasing per-urb latency by sharing interrupts. + * Drivers that queue bulk urbs may request that behavior. + */ + if (index != (urb_priv->length - 1) + || (urb->transfer_flags & URB_NO_INTERRUPT)) + info |= TD_DI_SET (6); + + /* use this td as the next dummy */ + td_pt = urb_priv->td [index]; + + /* fill the old dummy TD */ + td = urb_priv->td [index] = urb_priv->ed->dummy; + urb_priv->ed->dummy = td_pt; + + td->ed = urb_priv->ed; + td->next_dl_td = NULL; + td->index = index; + td->urb = urb; + td->data_dma = data; + if (!len) + data = 0; + + td->hwINFO = cpu_to_hc32 (ohci, info); + if (is_iso) { + td->hwCBP = cpu_to_hc32 (ohci, data & 0xFFFFF000); + *ohci_hwPSWp(ohci, td, 0) = cpu_to_hc16 (ohci, + (data & 0x0FFF) | 0xE000); + td->ed->last_iso = info & 0xffff; + } else { + td->hwCBP = cpu_to_hc32 (ohci, data); + } + if (data) + td->hwBE = cpu_to_hc32 (ohci, data + len - 1); + else + td->hwBE = 0; + td->hwNextTD = cpu_to_hc32 (ohci, td_pt->td_dma); + + /* append to queue */ + list_add_tail (&td->td_list, &td->ed->td_list); + + /* hash it for later reverse mapping */ + hash = TD_HASH_FUNC (td->td_dma); + td->td_hash = ohci->td_hash [hash]; + ohci->td_hash [hash] = td; + + /* HC might read the TD (or cachelines) right away ... */ + wmb (); + td->ed->hwTailP = td->hwNextTD; +} + +/*-------------------------------------------------------------------------*/ + +/* Prepare all TDs of a transfer, and queue them onto the ED. + * Caller guarantees HC is active. + * Usually the ED is already on the schedule, so TDs might be + * processed as soon as they're queued. + */ +static void td_submit_urb ( + struct ohci_hcd *ohci, + struct urb *urb +) { + struct urb_priv *urb_priv = urb->hcpriv; + dma_addr_t data; + int data_len = urb->transfer_buffer_length; + int cnt = 0; + u32 info = 0; + int is_out = usb_pipeout (urb->pipe); + int periodic = 0; + + /* OHCI handles the bulk/interrupt data toggles itself. We just + * use the device toggle bits for resetting, and rely on the fact + * that resetting toggle is meaningless if the endpoint is active. + */ + if (!usb_gettoggle (urb->dev, usb_pipeendpoint (urb->pipe), is_out)) { + usb_settoggle (urb->dev, usb_pipeendpoint (urb->pipe), + is_out, 1); + urb_priv->ed->hwHeadP &= ~cpu_to_hc32 (ohci, ED_C); + } + + urb_priv->td_cnt = 0; + list_add (&urb_priv->pending, &ohci->pending); + + if (data_len) + data = urb->transfer_dma; + else + data = 0; + + /* NOTE: TD_CC is set so we can tell which TDs the HC processed by + * using TD_CC_GET, as well as by seeing them on the done list. + * (CC = NotAccessed ... 0x0F, or 0x0E in PSWs for ISO.) + */ + switch (urb_priv->ed->type) { + + /* Bulk and interrupt are identical except for where in the schedule + * their EDs live. + */ + case PIPE_INTERRUPT: + /* ... and periodic urbs have extra accounting */ + periodic = ohci_to_hcd(ohci)->self.bandwidth_int_reqs++ == 0 + && ohci_to_hcd(ohci)->self.bandwidth_isoc_reqs == 0; + /* FALLTHROUGH */ + case PIPE_BULK: + info = is_out + ? TD_T_TOGGLE | TD_CC | TD_DP_OUT + : TD_T_TOGGLE | TD_CC | TD_DP_IN; + /* TDs _could_ transfer up to 8K each */ + while (data_len > 4096) { + td_fill (ohci, info, data, 4096, urb, cnt); + data += 4096; + data_len -= 4096; + cnt++; + } + /* maybe avoid ED halt on final TD short read */ + if (!(urb->transfer_flags & URB_SHORT_NOT_OK)) + info |= TD_R; + td_fill (ohci, info, data, data_len, urb, cnt); + cnt++; + if ((urb->transfer_flags & URB_ZERO_PACKET) + && cnt < urb_priv->length) { + td_fill (ohci, info, 0, 0, urb, cnt); + cnt++; + } + /* maybe kickstart bulk list */ + if (urb_priv->ed->type == PIPE_BULK) { + wmb (); + ohci_writel (ohci, OHCI_BLF, &ohci->regs->cmdstatus); + } + break; + + /* control manages DATA0/DATA1 toggle per-request; SETUP resets it, + * any DATA phase works normally, and the STATUS ack is special. + */ + case PIPE_CONTROL: + info = TD_CC | TD_DP_SETUP | TD_T_DATA0; + td_fill (ohci, info, urb->setup_dma, 8, urb, cnt++); + if (data_len > 0) { + info = TD_CC | TD_R | TD_T_DATA1; + info |= is_out ? TD_DP_OUT : TD_DP_IN; + /* NOTE: mishandles transfers >8K, some >4K */ + td_fill (ohci, info, data, data_len, urb, cnt++); + } + info = (is_out || data_len == 0) + ? TD_CC | TD_DP_IN | TD_T_DATA1 + : TD_CC | TD_DP_OUT | TD_T_DATA1; + td_fill (ohci, info, data, 0, urb, cnt++); + /* maybe kickstart control list */ + wmb (); + ohci_writel (ohci, OHCI_CLF, &ohci->regs->cmdstatus); + break; + + /* ISO has no retransmit, so no toggle; and it uses special TDs. + * Each TD could handle multiple consecutive frames (interval 1); + * we could often reduce the number of TDs here. + */ + case PIPE_ISOCHRONOUS: + for (cnt = 0; cnt < urb->number_of_packets; cnt++) { + int frame = urb->start_frame; + + // FIXME scheduling should handle frame counter + // roll-around ... exotic case (and OHCI has + // a 2^16 iso range, vs other HCs max of 2^10) + frame += cnt * urb->interval; + frame &= 0xffff; + td_fill (ohci, TD_CC | TD_ISO | frame, + data + urb->iso_frame_desc [cnt].offset, + urb->iso_frame_desc [cnt].length, urb, cnt); + } + periodic = ohci_to_hcd(ohci)->self.bandwidth_isoc_reqs++ == 0 + && ohci_to_hcd(ohci)->self.bandwidth_int_reqs == 0; + break; + } + + /* start periodic dma if needed */ + if (periodic) { + wmb (); + ohci->hc_control |= OHCI_CTRL_PLE|OHCI_CTRL_IE; + ohci_writel (ohci, ohci->hc_control, &ohci->regs->control); + } + + // ASSERT (urb_priv->length == cnt); +} + +/*-------------------------------------------------------------------------* + * Done List handling functions + *-------------------------------------------------------------------------*/ + +/* calculate transfer length/status and update the urb + * PRECONDITION: irqsafe (only for urb->status locking) + */ +static void td_done (struct ohci_hcd *ohci, struct urb *urb, struct td *td) +{ + u32 tdINFO = hc32_to_cpup (ohci, &td->hwINFO); + int cc = 0; + + list_del (&td->td_list); + + /* ISO ... drivers see per-TD length/status */ + if (tdINFO & TD_ISO) { + u16 tdPSW = ohci_hwPSW (ohci, td, 0); + int dlen = 0; + + /* NOTE: assumes FC in tdINFO == 0, and that + * only the first of 0..MAXPSW psws is used. + */ + + cc = (tdPSW >> 12) & 0xF; + if (tdINFO & TD_CC) /* hc didn't touch? */ + return; + + if (usb_pipeout (urb->pipe)) + dlen = urb->iso_frame_desc [td->index].length; + else { + /* short reads are always OK for ISO */ + if (cc == TD_DATAUNDERRUN) + cc = TD_CC_NOERROR; + dlen = tdPSW & 0x3ff; + } + urb->actual_length += dlen; + urb->iso_frame_desc [td->index].actual_length = dlen; + urb->iso_frame_desc [td->index].status = cc_to_error [cc]; + + if (cc != TD_CC_NOERROR) + ohci_vdbg (ohci, + "urb %p iso td %p (%d) len %d cc %d\n", + urb, td, 1 + td->index, dlen, cc); + + /* BULK, INT, CONTROL ... drivers see aggregate length/status, + * except that "setup" bytes aren't counted and "short" transfers + * might not be reported as errors. + */ + } else { + int type = usb_pipetype (urb->pipe); + u32 tdBE = hc32_to_cpup (ohci, &td->hwBE); + + cc = TD_CC_GET (tdINFO); + + /* update packet status if needed (short is normally ok) */ + if (cc == TD_DATAUNDERRUN + && !(urb->transfer_flags & URB_SHORT_NOT_OK)) + cc = TD_CC_NOERROR; + if (cc != TD_CC_NOERROR && cc < 0x0E) { + spin_lock (&urb->lock); + if (urb->status == -EINPROGRESS) + urb->status = cc_to_error [cc]; + spin_unlock (&urb->lock); + } + + /* count all non-empty packets except control SETUP packet */ + if ((type != PIPE_CONTROL || td->index != 0) && tdBE != 0) { + if (td->hwCBP == 0) + urb->actual_length += tdBE - td->data_dma + 1; + else + urb->actual_length += + hc32_to_cpup (ohci, &td->hwCBP) + - td->data_dma; + } + + if (cc != TD_CC_NOERROR && cc < 0x0E) + ohci_vdbg (ohci, + "urb %p td %p (%d) cc %d, len=%d/%d\n", + urb, td, 1 + td->index, cc, + urb->actual_length, + urb->transfer_buffer_length); + } +} + +/*-------------------------------------------------------------------------*/ + +static inline struct td * +ed_halted (struct ohci_hcd *ohci, struct td *td, int cc, struct td *rev) +{ + struct urb *urb = td->urb; + struct ed *ed = td->ed; + struct list_head *tmp = td->td_list.next; + __hc32 toggle = ed->hwHeadP & cpu_to_hc32 (ohci, ED_C); + + /* clear ed halt; this is the td that caused it, but keep it inactive + * until its urb->complete() has a chance to clean up. + */ + ed->hwINFO |= cpu_to_hc32 (ohci, ED_SKIP); + wmb (); + ed->hwHeadP &= ~cpu_to_hc32 (ohci, ED_H); + + /* put any later tds from this urb onto the donelist, after 'td', + * order won't matter here: no errors, and nothing was transferred. + * also patch the ed so it looks as if those tds completed normally. + */ + while (tmp != &ed->td_list) { + struct td *next; + __hc32 info; + + next = list_entry (tmp, struct td, td_list); + tmp = next->td_list.next; + + if (next->urb != urb) + break; + + /* NOTE: if multi-td control DATA segments get supported, + * this urb had one of them, this td wasn't the last td + * in that segment (TD_R clear), this ed halted because + * of a short read, _and_ URB_SHORT_NOT_OK is clear ... + * then we need to leave the control STATUS packet queued + * and clear ED_SKIP. + */ + info = next->hwINFO; + info |= cpu_to_hc32 (ohci, TD_DONE); + info &= ~cpu_to_hc32 (ohci, TD_CC); + next->hwINFO = info; + + next->next_dl_td = rev; + rev = next; + + ed->hwHeadP = next->hwNextTD | toggle; + } + + /* help for troubleshooting: report anything that + * looks odd ... that doesn't include protocol stalls + * (or maybe some other things) + */ + switch (cc) { + case TD_DATAUNDERRUN: + if ((urb->transfer_flags & URB_SHORT_NOT_OK) == 0) + break; + /* fallthrough */ + case TD_CC_STALL: + if (usb_pipecontrol (urb->pipe)) + break; + /* fallthrough */ + default: + ohci_dbg (ohci, + "urb %p path %s ep%d%s %08x cc %d --> status %d\n", + urb, urb->dev->devpath, + usb_pipeendpoint (urb->pipe), + usb_pipein (urb->pipe) ? "in" : "out", + hc32_to_cpu (ohci, td->hwINFO), + cc, cc_to_error [cc]); + } + + return rev; +} + +/* replies to the request have to be on a FIFO basis so + * we unreverse the hc-reversed done-list + */ +static struct td *dl_reverse_done_list (struct ohci_hcd *ohci) +{ + u32 td_dma; + struct td *td_rev = NULL; + struct td *td = NULL; + + td_dma = hc32_to_cpup (ohci, &ohci->hcca->done_head); + ohci->hcca->done_head = 0; + wmb(); + + /* get TD from hc's singly linked list, and + * prepend to ours. ed->td_list changes later. + */ + while (td_dma) { + int cc; + + td = dma_to_td (ohci, td_dma); + if (!td) { + ohci_err (ohci, "bad entry %8x\n", td_dma); + break; + } + + td->hwINFO |= cpu_to_hc32 (ohci, TD_DONE); + cc = TD_CC_GET (hc32_to_cpup (ohci, &td->hwINFO)); + + /* Non-iso endpoints can halt on error; un-halt, + * and dequeue any other TDs from this urb. + * No other TD could have caused the halt. + */ + if (cc != TD_CC_NOERROR + && (td->ed->hwHeadP & cpu_to_hc32 (ohci, ED_H))) + td_rev = ed_halted (ohci, td, cc, td_rev); + + td->next_dl_td = td_rev; + td_rev = td; + td_dma = hc32_to_cpup (ohci, &td->hwNextTD); + } + return td_rev; +} + +/*-------------------------------------------------------------------------*/ + +/* there are some urbs/eds to unlink; called in_irq(), with HCD locked */ +static void +finish_unlinks (struct ohci_hcd *ohci, u16 tick, struct pt_regs *regs) +{ + struct ed *ed, **last; + +rescan_all: + for (last = &ohci->ed_rm_list, ed = *last; ed != NULL; ed = *last) { + struct list_head *entry, *tmp; + int completed, modified; + __hc32 *prev; + + /* only take off EDs that the HC isn't using, accounting for + * frame counter wraps and EDs with partially retired TDs + */ + if (likely (regs && HC_IS_RUNNING(ohci_to_hcd(ohci)->state))) { + if (tick_before (tick, ed->tick)) { +skip_ed: + last = &ed->ed_next; + continue; + } + + if (!list_empty (&ed->td_list)) { + struct td *td; + u32 head; + + td = list_entry (ed->td_list.next, struct td, + td_list); + head = hc32_to_cpu (ohci, ed->hwHeadP) & + TD_MASK; + + /* INTR_WDH may need to clean up first */ + if (td->td_dma != head) + goto skip_ed; + } + } + + /* reentrancy: if we drop the schedule lock, someone might + * have modified this list. normally it's just prepending + * entries (which we'd ignore), but paranoia won't hurt. + */ + *last = ed->ed_next; + ed->ed_next = NULL; + modified = 0; + + /* unlink urbs as requested, but rescan the list after + * we call a completion since it might have unlinked + * another (earlier) urb + * + * When we get here, the HC doesn't see this ed. But it + * must not be rescheduled until all completed URBs have + * been given back to the driver. + */ +rescan_this: + completed = 0; + prev = &ed->hwHeadP; + list_for_each_safe (entry, tmp, &ed->td_list) { + struct td *td; + struct urb *urb; + urb_priv_t *urb_priv; + __hc32 savebits; + + td = list_entry (entry, struct td, td_list); + urb = td->urb; + urb_priv = td->urb->hcpriv; + + if (urb->status == -EINPROGRESS) { + prev = &td->hwNextTD; + continue; + } + + /* patch pointer hc uses */ + savebits = *prev & ~cpu_to_hc32 (ohci, TD_MASK); + *prev = td->hwNextTD | savebits; + + /* HC may have partly processed this TD */ + td_done (ohci, urb, td); + urb_priv->td_cnt++; + + /* if URB is done, clean up */ + if (urb_priv->td_cnt == urb_priv->length) { + modified = completed = 1; + finish_urb (ohci, urb, regs); + } + } + if (completed && !list_empty (&ed->td_list)) + goto rescan_this; + + /* ED's now officially unlinked, hc doesn't see */ + ed->state = ED_IDLE; + ed->hwHeadP &= ~cpu_to_hc32(ohci, ED_H); + ed->hwNextED = 0; + wmb (); + ed->hwINFO &= ~cpu_to_hc32 (ohci, ED_SKIP | ED_DEQUEUE); + + /* but if there's work queued, reschedule */ + if (!list_empty (&ed->td_list)) { + if (HC_IS_RUNNING(ohci_to_hcd(ohci)->state)) + ed_schedule (ohci, ed); + } + + if (modified) + goto rescan_all; + } + + /* maybe reenable control and bulk lists */ + if (HC_IS_RUNNING(ohci_to_hcd(ohci)->state) + && ohci_to_hcd(ohci)->state != HC_STATE_QUIESCING + && !ohci->ed_rm_list) { + u32 command = 0, control = 0; + + if (ohci->ed_controltail) { + command |= OHCI_CLF; + if (!(ohci->hc_control & OHCI_CTRL_CLE)) { + control |= OHCI_CTRL_CLE; + ohci_writel (ohci, 0, + &ohci->regs->ed_controlcurrent); + } + } + if (ohci->ed_bulktail) { + command |= OHCI_BLF; + if (!(ohci->hc_control & OHCI_CTRL_BLE)) { + control |= OHCI_CTRL_BLE; + ohci_writel (ohci, 0, + &ohci->regs->ed_bulkcurrent); + } + } + + /* CLE/BLE to enable, CLF/BLF to (maybe) kickstart */ + if (control) { + ohci->hc_control |= control; + ohci_writel (ohci, ohci->hc_control, + &ohci->regs->control); + } + if (command) + ohci_writel (ohci, command, &ohci->regs->cmdstatus); + } +} + + + +/*-------------------------------------------------------------------------*/ + +/* + * Process normal completions (error or success) and clean the schedules. + * + * This is the main path for handing urbs back to drivers. The only other + * path is finish_unlinks(), which unlinks URBs using ed_rm_list, instead of + * scanning the (re-reversed) donelist as this does. + */ +static void +dl_done_list (struct ohci_hcd *ohci, struct pt_regs *regs) +{ + struct td *td = dl_reverse_done_list (ohci); + + while (td) { + struct td *td_next = td->next_dl_td; + struct urb *urb = td->urb; + urb_priv_t *urb_priv = urb->hcpriv; + struct ed *ed = td->ed; + + /* update URB's length and status from TD */ + td_done (ohci, urb, td); + urb_priv->td_cnt++; + + /* If all this urb's TDs are done, call complete() */ + if (urb_priv->td_cnt == urb_priv->length) + finish_urb (ohci, urb, regs); + + /* clean schedule: unlink EDs that are no longer busy */ + if (list_empty (&ed->td_list)) { + if (ed->state == ED_OPER) + start_ed_unlink (ohci, ed); + + /* ... reenabling halted EDs only after fault cleanup */ + } else if ((ed->hwINFO & cpu_to_hc32 (ohci, ED_SKIP | ED_DEQUEUE)) + == cpu_to_hc32 (ohci, ED_SKIP)) { + td = list_entry (ed->td_list.next, struct td, td_list); + if (!(td->hwINFO & cpu_to_hc32 (ohci, TD_DONE))) { + ed->hwINFO &= ~cpu_to_hc32 (ohci, ED_SKIP); + /* ... hc may need waking-up */ + switch (ed->type) { + case PIPE_CONTROL: + ohci_writel (ohci, OHCI_CLF, + &ohci->regs->cmdstatus); + break; + case PIPE_BULK: + ohci_writel (ohci, OHCI_BLF, + &ohci->regs->cmdstatus); + break; + } + } + } + + td = td_next; + } +} |