| /* |
| * Copyright (C) 2001-2004 by David Brownell |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License as published by the |
| * Free Software Foundation; either version 2 of the License, or (at your |
| * option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, but |
| * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
| * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software Foundation, |
| * Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| */ |
| |
| /* this file is part of ehci-hcd.c */ |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* |
| * EHCI hardware queue manipulation ... the core. QH/QTD manipulation. |
| * |
| * Control, bulk, and interrupt traffic all use "qh" lists. They list "qtd" |
| * entries describing USB transactions, max 16-20kB/entry (with 4kB-aligned |
| * buffers needed for the larger number). We use one QH per endpoint, queue |
| * multiple urbs (all three types) per endpoint. URBs may need several qtds. |
| * |
| * ISO traffic uses "ISO TD" (itd, and sitd) records, and (along with |
| * interrupts) needs careful scheduling. Performance improvements can be |
| * an ongoing challenge. That's in "ehci-sched.c". |
| * |
| * USB 1.1 devices are handled (a) by "companion" OHCI or UHCI root hubs, |
| * or otherwise through transaction translators (TTs) in USB 2.0 hubs using |
| * (b) special fields in qh entries or (c) split iso entries. TTs will |
| * buffer low/full speed data so the host collects it at high speed. |
| */ |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* fill a qtd, returning how much of the buffer we were able to queue up */ |
| |
| static int |
| qtd_fill (struct ehci_qtd *qtd, dma_addr_t buf, size_t len, |
| int token, int maxpacket) |
| { |
| int i, count; |
| u64 addr = buf; |
| |
| /* one buffer entry per 4K ... first might be short or unaligned */ |
| qtd->hw_buf [0] = cpu_to_le32 ((u32)addr); |
| qtd->hw_buf_hi [0] = cpu_to_le32 ((u32)(addr >> 32)); |
| count = 0x1000 - (buf & 0x0fff); /* rest of that page */ |
| if (likely (len < count)) /* ... iff needed */ |
| count = len; |
| else { |
| buf += 0x1000; |
| buf &= ~0x0fff; |
| |
| /* per-qtd limit: from 16K to 20K (best alignment) */ |
| for (i = 1; count < len && i < 5; i++) { |
| addr = buf; |
| qtd->hw_buf [i] = cpu_to_le32 ((u32)addr); |
| qtd->hw_buf_hi [i] = cpu_to_le32 ((u32)(addr >> 32)); |
| buf += 0x1000; |
| if ((count + 0x1000) < len) |
| count += 0x1000; |
| else |
| count = len; |
| } |
| |
| /* short packets may only terminate transfers */ |
| if (count != len) |
| count -= (count % maxpacket); |
| } |
| qtd->hw_token = cpu_to_le32 ((count << 16) | token); |
| qtd->length = count; |
| |
| return count; |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| static inline void |
| qh_update (struct ehci_hcd *ehci, struct ehci_qh *qh, struct ehci_qtd *qtd) |
| { |
| /* writes to an active overlay are unsafe */ |
| BUG_ON(qh->qh_state != QH_STATE_IDLE); |
| |
| qh->hw_qtd_next = QTD_NEXT (qtd->qtd_dma); |
| qh->hw_alt_next = EHCI_LIST_END; |
| |
| /* Except for control endpoints, we make hardware maintain data |
| * toggle (like OHCI) ... here (re)initialize the toggle in the QH, |
| * and set the pseudo-toggle in udev. Only usb_clear_halt() will |
| * ever clear it. |
| */ |
| if (!(qh->hw_info1 & cpu_to_le32(1 << 14))) { |
| unsigned is_out, epnum; |
| |
| is_out = !(qtd->hw_token & cpu_to_le32(1 << 8)); |
| epnum = (le32_to_cpup(&qh->hw_info1) >> 8) & 0x0f; |
| if (unlikely (!usb_gettoggle (qh->dev, epnum, is_out))) { |
| qh->hw_token &= ~__constant_cpu_to_le32 (QTD_TOGGLE); |
| usb_settoggle (qh->dev, epnum, is_out, 1); |
| } |
| } |
| |
| /* HC must see latest qtd and qh data before we clear ACTIVE+HALT */ |
| wmb (); |
| qh->hw_token &= __constant_cpu_to_le32 (QTD_TOGGLE | QTD_STS_PING); |
| } |
| |
| /* if it weren't for a common silicon quirk (writing the dummy into the qh |
| * overlay, so qh->hw_token wrongly becomes inactive/halted), only fault |
| * recovery (including urb dequeue) would need software changes to a QH... |
| */ |
| static void |
| qh_refresh (struct ehci_hcd *ehci, struct ehci_qh *qh) |
| { |
| struct ehci_qtd *qtd; |
| |
| if (list_empty (&qh->qtd_list)) |
| qtd = qh->dummy; |
| else { |
| qtd = list_entry (qh->qtd_list.next, |
| struct ehci_qtd, qtd_list); |
| /* first qtd may already be partially processed */ |
| if (cpu_to_le32 (qtd->qtd_dma) == qh->hw_current) |
| qtd = NULL; |
| } |
| |
| if (qtd) |
| qh_update (ehci, qh, qtd); |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| static void qtd_copy_status ( |
| struct ehci_hcd *ehci, |
| struct urb *urb, |
| size_t length, |
| u32 token |
| ) |
| { |
| /* count IN/OUT bytes, not SETUP (even short packets) */ |
| if (likely (QTD_PID (token) != 2)) |
| urb->actual_length += length - QTD_LENGTH (token); |
| |
| /* don't modify error codes */ |
| if (unlikely (urb->status != -EINPROGRESS)) |
| return; |
| |
| /* force cleanup after short read; not always an error */ |
| if (unlikely (IS_SHORT_READ (token))) |
| urb->status = -EREMOTEIO; |
| |
| /* serious "can't proceed" faults reported by the hardware */ |
| if (token & QTD_STS_HALT) { |
| if (token & QTD_STS_BABBLE) { |
| /* FIXME "must" disable babbling device's port too */ |
| urb->status = -EOVERFLOW; |
| } else if (token & QTD_STS_MMF) { |
| /* fs/ls interrupt xfer missed the complete-split */ |
| urb->status = -EPROTO; |
| } else if (token & QTD_STS_DBE) { |
| urb->status = (QTD_PID (token) == 1) /* IN ? */ |
| ? -ENOSR /* hc couldn't read data */ |
| : -ECOMM; /* hc couldn't write data */ |
| } else if (token & QTD_STS_XACT) { |
| /* timeout, bad crc, wrong PID, etc; retried */ |
| if (QTD_CERR (token)) |
| urb->status = -EPIPE; |
| else { |
| ehci_dbg (ehci, "devpath %s ep%d%s 3strikes\n", |
| urb->dev->devpath, |
| usb_pipeendpoint (urb->pipe), |
| usb_pipein (urb->pipe) ? "in" : "out"); |
| urb->status = -EPROTO; |
| } |
| /* CERR nonzero + no errors + halt --> stall */ |
| } else if (QTD_CERR (token)) |
| urb->status = -EPIPE; |
| else /* unknown */ |
| urb->status = -EPROTO; |
| |
| ehci_vdbg (ehci, |
| "dev%d ep%d%s qtd token %08x --> status %d\n", |
| usb_pipedevice (urb->pipe), |
| usb_pipeendpoint (urb->pipe), |
| usb_pipein (urb->pipe) ? "in" : "out", |
| token, urb->status); |
| |
| /* if async CSPLIT failed, try cleaning out the TT buffer */ |
| if (urb->status != -EPIPE |
| && urb->dev->tt && !usb_pipeint (urb->pipe) |
| && ((token & QTD_STS_MMF) != 0 |
| || QTD_CERR(token) == 0) |
| && (!ehci_is_TDI(ehci) |
| || urb->dev->tt->hub != |
| ehci_to_hcd(ehci)->self.root_hub)) { |
| #ifdef DEBUG |
| struct usb_device *tt = urb->dev->tt->hub; |
| dev_dbg (&tt->dev, |
| "clear tt buffer port %d, a%d ep%d t%08x\n", |
| urb->dev->ttport, urb->dev->devnum, |
| usb_pipeendpoint (urb->pipe), token); |
| #endif /* DEBUG */ |
| usb_hub_tt_clear_buffer (urb->dev, urb->pipe); |
| } |
| } |
| } |
| |
| static void |
| ehci_urb_done (struct ehci_hcd *ehci, struct urb *urb, struct pt_regs *regs) |
| __releases(ehci->lock) |
| __acquires(ehci->lock) |
| { |
| if (likely (urb->hcpriv != NULL)) { |
| struct ehci_qh *qh = (struct ehci_qh *) urb->hcpriv; |
| |
| /* S-mask in a QH means it's an interrupt urb */ |
| if ((qh->hw_info2 & __constant_cpu_to_le32 (QH_SMASK)) != 0) { |
| |
| /* ... update hc-wide periodic stats (for usbfs) */ |
| ehci_to_hcd(ehci)->self.bandwidth_int_reqs--; |
| } |
| qh_put (qh); |
| } |
| |
| spin_lock (&urb->lock); |
| urb->hcpriv = NULL; |
| switch (urb->status) { |
| case -EINPROGRESS: /* success */ |
| urb->status = 0; |
| default: /* fault */ |
| COUNT (ehci->stats.complete); |
| break; |
| case -EREMOTEIO: /* fault or normal */ |
| if (!(urb->transfer_flags & URB_SHORT_NOT_OK)) |
| urb->status = 0; |
| COUNT (ehci->stats.complete); |
| break; |
| case -ECONNRESET: /* canceled */ |
| case -ENOENT: |
| COUNT (ehci->stats.unlink); |
| break; |
| } |
| spin_unlock (&urb->lock); |
| |
| #ifdef EHCI_URB_TRACE |
| ehci_dbg (ehci, |
| "%s %s urb %p ep%d%s status %d len %d/%d\n", |
| __FUNCTION__, urb->dev->devpath, urb, |
| usb_pipeendpoint (urb->pipe), |
| usb_pipein (urb->pipe) ? "in" : "out", |
| urb->status, |
| urb->actual_length, urb->transfer_buffer_length); |
| #endif |
| |
| /* complete() can reenter this HCD */ |
| spin_unlock (&ehci->lock); |
| usb_hcd_giveback_urb (ehci_to_hcd(ehci), urb, regs); |
| spin_lock (&ehci->lock); |
| } |
| |
| static void start_unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh); |
| static void unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh); |
| |
| static void intr_deschedule (struct ehci_hcd *ehci, struct ehci_qh *qh); |
| static int qh_schedule (struct ehci_hcd *ehci, struct ehci_qh *qh); |
| |
| /* |
| * Process and free completed qtds for a qh, returning URBs to drivers. |
| * Chases up to qh->hw_current. Returns number of completions called, |
| * indicating how much "real" work we did. |
| */ |
| #define HALT_BIT __constant_cpu_to_le32(QTD_STS_HALT) |
| static unsigned |
| qh_completions (struct ehci_hcd *ehci, struct ehci_qh *qh, struct pt_regs *regs) |
| { |
| struct ehci_qtd *last = NULL, *end = qh->dummy; |
| struct list_head *entry, *tmp; |
| int stopped; |
| unsigned count = 0; |
| int do_status = 0; |
| u8 state; |
| |
| if (unlikely (list_empty (&qh->qtd_list))) |
| return count; |
| |
| /* completions (or tasks on other cpus) must never clobber HALT |
| * till we've gone through and cleaned everything up, even when |
| * they add urbs to this qh's queue or mark them for unlinking. |
| * |
| * NOTE: unlinking expects to be done in queue order. |
| */ |
| state = qh->qh_state; |
| qh->qh_state = QH_STATE_COMPLETING; |
| stopped = (state == QH_STATE_IDLE); |
| |
| /* remove de-activated QTDs from front of queue. |
| * after faults (including short reads), cleanup this urb |
| * then let the queue advance. |
| * if queue is stopped, handles unlinks. |
| */ |
| list_for_each_safe (entry, tmp, &qh->qtd_list) { |
| struct ehci_qtd *qtd; |
| struct urb *urb; |
| u32 token = 0; |
| |
| qtd = list_entry (entry, struct ehci_qtd, qtd_list); |
| urb = qtd->urb; |
| |
| /* clean up any state from previous QTD ...*/ |
| if (last) { |
| if (likely (last->urb != urb)) { |
| ehci_urb_done (ehci, last->urb, regs); |
| count++; |
| } |
| ehci_qtd_free (ehci, last); |
| last = NULL; |
| } |
| |
| /* ignore urbs submitted during completions we reported */ |
| if (qtd == end) |
| break; |
| |
| /* hardware copies qtd out of qh overlay */ |
| rmb (); |
| token = le32_to_cpu (qtd->hw_token); |
| |
| /* always clean up qtds the hc de-activated */ |
| if ((token & QTD_STS_ACTIVE) == 0) { |
| |
| if ((token & QTD_STS_HALT) != 0) { |
| stopped = 1; |
| |
| /* magic dummy for some short reads; qh won't advance. |
| * that silicon quirk can kick in with this dummy too. |
| */ |
| } else if (IS_SHORT_READ (token) |
| && !(qtd->hw_alt_next & EHCI_LIST_END)) { |
| stopped = 1; |
| goto halt; |
| } |
| |
| /* stop scanning when we reach qtds the hc is using */ |
| } else if (likely (!stopped |
| && HC_IS_RUNNING (ehci_to_hcd(ehci)->state))) { |
| break; |
| |
| } else { |
| stopped = 1; |
| |
| if (unlikely (!HC_IS_RUNNING (ehci_to_hcd(ehci)->state))) |
| urb->status = -ESHUTDOWN; |
| |
| /* ignore active urbs unless some previous qtd |
| * for the urb faulted (including short read) or |
| * its urb was canceled. we may patch qh or qtds. |
| */ |
| if (likely (urb->status == -EINPROGRESS)) |
| continue; |
| |
| /* issue status after short control reads */ |
| if (unlikely (do_status != 0) |
| && QTD_PID (token) == 0 /* OUT */) { |
| do_status = 0; |
| continue; |
| } |
| |
| /* token in overlay may be most current */ |
| if (state == QH_STATE_IDLE |
| && cpu_to_le32 (qtd->qtd_dma) |
| == qh->hw_current) |
| token = le32_to_cpu (qh->hw_token); |
| |
| /* force halt for unlinked or blocked qh, so we'll |
| * patch the qh later and so that completions can't |
| * activate it while we "know" it's stopped. |
| */ |
| if ((HALT_BIT & qh->hw_token) == 0) { |
| halt: |
| qh->hw_token |= HALT_BIT; |
| wmb (); |
| } |
| } |
| |
| /* remove it from the queue */ |
| spin_lock (&urb->lock); |
| qtd_copy_status (ehci, urb, qtd->length, token); |
| do_status = (urb->status == -EREMOTEIO) |
| && usb_pipecontrol (urb->pipe); |
| spin_unlock (&urb->lock); |
| |
| if (stopped && qtd->qtd_list.prev != &qh->qtd_list) { |
| last = list_entry (qtd->qtd_list.prev, |
| struct ehci_qtd, qtd_list); |
| last->hw_next = qtd->hw_next; |
| } |
| list_del (&qtd->qtd_list); |
| last = qtd; |
| } |
| |
| /* last urb's completion might still need calling */ |
| if (likely (last != NULL)) { |
| ehci_urb_done (ehci, last->urb, regs); |
| count++; |
| ehci_qtd_free (ehci, last); |
| } |
| |
| /* restore original state; caller must unlink or relink */ |
| qh->qh_state = state; |
| |
| /* be sure the hardware's done with the qh before refreshing |
| * it after fault cleanup, or recovering from silicon wrongly |
| * overlaying the dummy qtd (which reduces DMA chatter). |
| */ |
| if (stopped != 0 || qh->hw_qtd_next == EHCI_LIST_END) { |
| switch (state) { |
| case QH_STATE_IDLE: |
| qh_refresh(ehci, qh); |
| break; |
| case QH_STATE_LINKED: |
| /* should be rare for periodic transfers, |
| * except maybe high bandwidth ... |
| */ |
| if ((__constant_cpu_to_le32 (QH_SMASK) |
| & qh->hw_info2) != 0) { |
| intr_deschedule (ehci, qh); |
| (void) qh_schedule (ehci, qh); |
| } else |
| unlink_async (ehci, qh); |
| break; |
| /* otherwise, unlink already started */ |
| } |
| } |
| |
| return count; |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| // high bandwidth multiplier, as encoded in highspeed endpoint descriptors |
| #define hb_mult(wMaxPacketSize) (1 + (((wMaxPacketSize) >> 11) & 0x03)) |
| // ... and packet size, for any kind of endpoint descriptor |
| #define max_packet(wMaxPacketSize) ((wMaxPacketSize) & 0x07ff) |
| |
| /* |
| * reverse of qh_urb_transaction: free a list of TDs. |
| * used for cleanup after errors, before HC sees an URB's TDs. |
| */ |
| static void qtd_list_free ( |
| struct ehci_hcd *ehci, |
| struct urb *urb, |
| struct list_head *qtd_list |
| ) { |
| struct list_head *entry, *temp; |
| |
| list_for_each_safe (entry, temp, qtd_list) { |
| struct ehci_qtd *qtd; |
| |
| qtd = list_entry (entry, struct ehci_qtd, qtd_list); |
| list_del (&qtd->qtd_list); |
| ehci_qtd_free (ehci, qtd); |
| } |
| } |
| |
| /* |
| * create a list of filled qtds for this URB; won't link into qh. |
| */ |
| static struct list_head * |
| qh_urb_transaction ( |
| struct ehci_hcd *ehci, |
| struct urb *urb, |
| struct list_head *head, |
| gfp_t flags |
| ) { |
| struct ehci_qtd *qtd, *qtd_prev; |
| dma_addr_t buf; |
| int len, maxpacket; |
| int is_input; |
| u32 token; |
| |
| /* |
| * URBs map to sequences of QTDs: one logical transaction |
| */ |
| qtd = ehci_qtd_alloc (ehci, flags); |
| if (unlikely (!qtd)) |
| return NULL; |
| list_add_tail (&qtd->qtd_list, head); |
| qtd->urb = urb; |
| |
| token = QTD_STS_ACTIVE; |
| token |= (EHCI_TUNE_CERR << 10); |
| /* for split transactions, SplitXState initialized to zero */ |
| |
| len = urb->transfer_buffer_length; |
| is_input = usb_pipein (urb->pipe); |
| if (usb_pipecontrol (urb->pipe)) { |
| /* SETUP pid */ |
| qtd_fill (qtd, urb->setup_dma, sizeof (struct usb_ctrlrequest), |
| token | (2 /* "setup" */ << 8), 8); |
| |
| /* ... and always at least one more pid */ |
| token ^= QTD_TOGGLE; |
| qtd_prev = qtd; |
| qtd = ehci_qtd_alloc (ehci, flags); |
| if (unlikely (!qtd)) |
| goto cleanup; |
| qtd->urb = urb; |
| qtd_prev->hw_next = QTD_NEXT (qtd->qtd_dma); |
| list_add_tail (&qtd->qtd_list, head); |
| } |
| |
| /* |
| * data transfer stage: buffer setup |
| */ |
| if (likely (len > 0)) |
| buf = urb->transfer_dma; |
| else |
| buf = 0; |
| |
| /* for zero length DATA stages, STATUS is always IN */ |
| if (!buf || is_input) |
| token |= (1 /* "in" */ << 8); |
| /* else it's already initted to "out" pid (0 << 8) */ |
| |
| maxpacket = max_packet(usb_maxpacket(urb->dev, urb->pipe, !is_input)); |
| |
| /* |
| * buffer gets wrapped in one or more qtds; |
| * last one may be "short" (including zero len) |
| * and may serve as a control status ack |
| */ |
| for (;;) { |
| int this_qtd_len; |
| |
| this_qtd_len = qtd_fill (qtd, buf, len, token, maxpacket); |
| len -= this_qtd_len; |
| buf += this_qtd_len; |
| if (is_input) |
| qtd->hw_alt_next = ehci->async->hw_alt_next; |
| |
| /* qh makes control packets use qtd toggle; maybe switch it */ |
| if ((maxpacket & (this_qtd_len + (maxpacket - 1))) == 0) |
| token ^= QTD_TOGGLE; |
| |
| if (likely (len <= 0)) |
| break; |
| |
| qtd_prev = qtd; |
| qtd = ehci_qtd_alloc (ehci, flags); |
| if (unlikely (!qtd)) |
| goto cleanup; |
| qtd->urb = urb; |
| qtd_prev->hw_next = QTD_NEXT (qtd->qtd_dma); |
| list_add_tail (&qtd->qtd_list, head); |
| } |
| |
| /* unless the bulk/interrupt caller wants a chance to clean |
| * up after short reads, hc should advance qh past this urb |
| */ |
| if (likely ((urb->transfer_flags & URB_SHORT_NOT_OK) == 0 |
| || usb_pipecontrol (urb->pipe))) |
| qtd->hw_alt_next = EHCI_LIST_END; |
| |
| /* |
| * control requests may need a terminating data "status" ack; |
| * bulk ones may need a terminating short packet (zero length). |
| */ |
| if (likely (buf != 0)) { |
| int one_more = 0; |
| |
| if (usb_pipecontrol (urb->pipe)) { |
| one_more = 1; |
| token ^= 0x0100; /* "in" <--> "out" */ |
| token |= QTD_TOGGLE; /* force DATA1 */ |
| } else if (usb_pipebulk (urb->pipe) |
| && (urb->transfer_flags & URB_ZERO_PACKET) |
| && !(urb->transfer_buffer_length % maxpacket)) { |
| one_more = 1; |
| } |
| if (one_more) { |
| qtd_prev = qtd; |
| qtd = ehci_qtd_alloc (ehci, flags); |
| if (unlikely (!qtd)) |
| goto cleanup; |
| qtd->urb = urb; |
| qtd_prev->hw_next = QTD_NEXT (qtd->qtd_dma); |
| list_add_tail (&qtd->qtd_list, head); |
| |
| /* never any data in such packets */ |
| qtd_fill (qtd, 0, 0, token, 0); |
| } |
| } |
| |
| /* by default, enable interrupt on urb completion */ |
| if (likely (!(urb->transfer_flags & URB_NO_INTERRUPT))) |
| qtd->hw_token |= __constant_cpu_to_le32 (QTD_IOC); |
| return head; |
| |
| cleanup: |
| qtd_list_free (ehci, urb, head); |
| return NULL; |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| // Would be best to create all qh's from config descriptors, |
| // when each interface/altsetting is established. Unlink |
| // any previous qh and cancel its urbs first; endpoints are |
| // implicitly reset then (data toggle too). |
| // That'd mean updating how usbcore talks to HCDs. (2.7?) |
| |
| |
| /* |
| * Each QH holds a qtd list; a QH is used for everything except iso. |
| * |
| * For interrupt urbs, the scheduler must set the microframe scheduling |
| * mask(s) each time the QH gets scheduled. For highspeed, that's |
| * just one microframe in the s-mask. For split interrupt transactions |
| * there are additional complications: c-mask, maybe FSTNs. |
| */ |
| static struct ehci_qh * |
| qh_make ( |
| struct ehci_hcd *ehci, |
| struct urb *urb, |
| gfp_t flags |
| ) { |
| struct ehci_qh *qh = ehci_qh_alloc (ehci, flags); |
| u32 info1 = 0, info2 = 0; |
| int is_input, type; |
| int maxp = 0; |
| |
| if (!qh) |
| return qh; |
| |
| /* |
| * init endpoint/device data for this QH |
| */ |
| info1 |= usb_pipeendpoint (urb->pipe) << 8; |
| info1 |= usb_pipedevice (urb->pipe) << 0; |
| |
| is_input = usb_pipein (urb->pipe); |
| type = usb_pipetype (urb->pipe); |
| maxp = usb_maxpacket (urb->dev, urb->pipe, !is_input); |
| |
| /* Compute interrupt scheduling parameters just once, and save. |
| * - allowing for high bandwidth, how many nsec/uframe are used? |
| * - split transactions need a second CSPLIT uframe; same question |
| * - splits also need a schedule gap (for full/low speed I/O) |
| * - qh has a polling interval |
| * |
| * For control/bulk requests, the HC or TT handles these. |
| */ |
| if (type == PIPE_INTERRUPT) { |
| qh->usecs = NS_TO_US (usb_calc_bus_time (USB_SPEED_HIGH, is_input, 0, |
| hb_mult (maxp) * max_packet (maxp))); |
| qh->start = NO_FRAME; |
| |
| if (urb->dev->speed == USB_SPEED_HIGH) { |
| qh->c_usecs = 0; |
| qh->gap_uf = 0; |
| |
| qh->period = urb->interval >> 3; |
| if (qh->period == 0 && urb->interval != 1) { |
| /* NOTE interval 2 or 4 uframes could work. |
| * But interval 1 scheduling is simpler, and |
| * includes high bandwidth. |
| */ |
| dbg ("intr period %d uframes, NYET!", |
| urb->interval); |
| goto done; |
| } |
| } else { |
| struct usb_tt *tt = urb->dev->tt; |
| int think_time; |
| |
| /* gap is f(FS/LS transfer times) */ |
| qh->gap_uf = 1 + usb_calc_bus_time (urb->dev->speed, |
| is_input, 0, maxp) / (125 * 1000); |
| |
| /* FIXME this just approximates SPLIT/CSPLIT times */ |
| if (is_input) { // SPLIT, gap, CSPLIT+DATA |
| qh->c_usecs = qh->usecs + HS_USECS (0); |
| qh->usecs = HS_USECS (1); |
| } else { // SPLIT+DATA, gap, CSPLIT |
| qh->usecs += HS_USECS (1); |
| qh->c_usecs = HS_USECS (0); |
| } |
| |
| think_time = tt ? tt->think_time : 0; |
| qh->tt_usecs = NS_TO_US (think_time + |
| usb_calc_bus_time (urb->dev->speed, |
| is_input, 0, max_packet (maxp))); |
| qh->period = urb->interval; |
| } |
| } |
| |
| /* support for tt scheduling, and access to toggles */ |
| qh->dev = usb_get_dev (urb->dev); |
| |
| /* using TT? */ |
| switch (urb->dev->speed) { |
| case USB_SPEED_LOW: |
| info1 |= (1 << 12); /* EPS "low" */ |
| /* FALL THROUGH */ |
| |
| case USB_SPEED_FULL: |
| /* EPS 0 means "full" */ |
| if (type != PIPE_INTERRUPT) |
| info1 |= (EHCI_TUNE_RL_TT << 28); |
| if (type == PIPE_CONTROL) { |
| info1 |= (1 << 27); /* for TT */ |
| info1 |= 1 << 14; /* toggle from qtd */ |
| } |
| info1 |= maxp << 16; |
| |
| info2 |= (EHCI_TUNE_MULT_TT << 30); |
| info2 |= urb->dev->ttport << 23; |
| |
| /* set the address of the TT; for TDI's integrated |
| * root hub tt, leave it zeroed. |
| */ |
| if (!ehci_is_TDI(ehci) |
| || urb->dev->tt->hub != |
| ehci_to_hcd(ehci)->self.root_hub) |
| info2 |= urb->dev->tt->hub->devnum << 16; |
| |
| /* NOTE: if (PIPE_INTERRUPT) { scheduler sets c-mask } */ |
| |
| break; |
| |
| case USB_SPEED_HIGH: /* no TT involved */ |
| info1 |= (2 << 12); /* EPS "high" */ |
| if (type == PIPE_CONTROL) { |
| info1 |= (EHCI_TUNE_RL_HS << 28); |
| info1 |= 64 << 16; /* usb2 fixed maxpacket */ |
| info1 |= 1 << 14; /* toggle from qtd */ |
| info2 |= (EHCI_TUNE_MULT_HS << 30); |
| } else if (type == PIPE_BULK) { |
| info1 |= (EHCI_TUNE_RL_HS << 28); |
| info1 |= 512 << 16; /* usb2 fixed maxpacket */ |
| info2 |= (EHCI_TUNE_MULT_HS << 30); |
| } else { /* PIPE_INTERRUPT */ |
| info1 |= max_packet (maxp) << 16; |
| info2 |= hb_mult (maxp) << 30; |
| } |
| break; |
| default: |
| dbg ("bogus dev %p speed %d", urb->dev, urb->dev->speed); |
| done: |
| qh_put (qh); |
| return NULL; |
| } |
| |
| /* NOTE: if (PIPE_INTERRUPT) { scheduler sets s-mask } */ |
| |
| /* init as live, toggle clear, advance to dummy */ |
| qh->qh_state = QH_STATE_IDLE; |
| qh->hw_info1 = cpu_to_le32 (info1); |
| qh->hw_info2 = cpu_to_le32 (info2); |
| usb_settoggle (urb->dev, usb_pipeendpoint (urb->pipe), !is_input, 1); |
| qh_refresh (ehci, qh); |
| return qh; |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* move qh (and its qtds) onto async queue; maybe enable queue. */ |
| |
| static void qh_link_async (struct ehci_hcd *ehci, struct ehci_qh *qh) |
| { |
| __le32 dma = QH_NEXT (qh->qh_dma); |
| struct ehci_qh *head; |
| |
| /* (re)start the async schedule? */ |
| head = ehci->async; |
| timer_action_done (ehci, TIMER_ASYNC_OFF); |
| if (!head->qh_next.qh) { |
| u32 cmd = readl (&ehci->regs->command); |
| |
| if (!(cmd & CMD_ASE)) { |
| /* in case a clear of CMD_ASE didn't take yet */ |
| (void) handshake (&ehci->regs->status, STS_ASS, 0, 150); |
| cmd |= CMD_ASE | CMD_RUN; |
| writel (cmd, &ehci->regs->command); |
| ehci_to_hcd(ehci)->state = HC_STATE_RUNNING; |
| /* posted write need not be known to HC yet ... */ |
| } |
| } |
| |
| /* clear halt and/or toggle; and maybe recover from silicon quirk */ |
| if (qh->qh_state == QH_STATE_IDLE) |
| qh_refresh (ehci, qh); |
| |
| /* splice right after start */ |
| qh->qh_next = head->qh_next; |
| qh->hw_next = head->hw_next; |
| wmb (); |
| |
| head->qh_next.qh = qh; |
| head->hw_next = dma; |
| |
| qh->qh_state = QH_STATE_LINKED; |
| /* qtd completions reported later by interrupt */ |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| #define QH_ADDR_MASK __constant_cpu_to_le32(0x7f) |
| |
| /* |
| * For control/bulk/interrupt, return QH with these TDs appended. |
| * Allocates and initializes the QH if necessary. |
| * Returns null if it can't allocate a QH it needs to. |
| * If the QH has TDs (urbs) already, that's great. |
| */ |
| static struct ehci_qh *qh_append_tds ( |
| struct ehci_hcd *ehci, |
| struct urb *urb, |
| struct list_head *qtd_list, |
| int epnum, |
| void **ptr |
| ) |
| { |
| struct ehci_qh *qh = NULL; |
| |
| qh = (struct ehci_qh *) *ptr; |
| if (unlikely (qh == NULL)) { |
| /* can't sleep here, we have ehci->lock... */ |
| qh = qh_make (ehci, urb, GFP_ATOMIC); |
| *ptr = qh; |
| } |
| if (likely (qh != NULL)) { |
| struct ehci_qtd *qtd; |
| |
| if (unlikely (list_empty (qtd_list))) |
| qtd = NULL; |
| else |
| qtd = list_entry (qtd_list->next, struct ehci_qtd, |
| qtd_list); |
| |
| /* control qh may need patching ... */ |
| if (unlikely (epnum == 0)) { |
| |
| /* usb_reset_device() briefly reverts to address 0 */ |
| if (usb_pipedevice (urb->pipe) == 0) |
| qh->hw_info1 &= ~QH_ADDR_MASK; |
| } |
| |
| /* just one way to queue requests: swap with the dummy qtd. |
| * only hc or qh_refresh() ever modify the overlay. |
| */ |
| if (likely (qtd != NULL)) { |
| struct ehci_qtd *dummy; |
| dma_addr_t dma; |
| __le32 token; |
| |
| /* to avoid racing the HC, use the dummy td instead of |
| * the first td of our list (becomes new dummy). both |
| * tds stay deactivated until we're done, when the |
| * HC is allowed to fetch the old dummy (4.10.2). |
| */ |
| token = qtd->hw_token; |
| qtd->hw_token = HALT_BIT; |
| wmb (); |
| dummy = qh->dummy; |
| |
| dma = dummy->qtd_dma; |
| *dummy = *qtd; |
| dummy->qtd_dma = dma; |
| |
| list_del (&qtd->qtd_list); |
| list_add (&dummy->qtd_list, qtd_list); |
| __list_splice (qtd_list, qh->qtd_list.prev); |
| |
| ehci_qtd_init (qtd, qtd->qtd_dma); |
| qh->dummy = qtd; |
| |
| /* hc must see the new dummy at list end */ |
| dma = qtd->qtd_dma; |
| qtd = list_entry (qh->qtd_list.prev, |
| struct ehci_qtd, qtd_list); |
| qtd->hw_next = QTD_NEXT (dma); |
| |
| /* let the hc process these next qtds */ |
| wmb (); |
| dummy->hw_token = token; |
| |
| urb->hcpriv = qh_get (qh); |
| } |
| } |
| return qh; |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| static int |
| submit_async ( |
| struct ehci_hcd *ehci, |
| struct usb_host_endpoint *ep, |
| struct urb *urb, |
| struct list_head *qtd_list, |
| gfp_t mem_flags |
| ) { |
| struct ehci_qtd *qtd; |
| int epnum; |
| unsigned long flags; |
| struct ehci_qh *qh = NULL; |
| |
| qtd = list_entry (qtd_list->next, struct ehci_qtd, qtd_list); |
| epnum = ep->desc.bEndpointAddress; |
| |
| #ifdef EHCI_URB_TRACE |
| ehci_dbg (ehci, |
| "%s %s urb %p ep%d%s len %d, qtd %p [qh %p]\n", |
| __FUNCTION__, urb->dev->devpath, urb, |
| epnum & 0x0f, (epnum & USB_DIR_IN) ? "in" : "out", |
| urb->transfer_buffer_length, |
| qtd, ep->hcpriv); |
| #endif |
| |
| spin_lock_irqsave (&ehci->lock, flags); |
| qh = qh_append_tds (ehci, urb, qtd_list, epnum, &ep->hcpriv); |
| |
| /* Control/bulk operations through TTs don't need scheduling, |
| * the HC and TT handle it when the TT has a buffer ready. |
| */ |
| if (likely (qh != NULL)) { |
| if (likely (qh->qh_state == QH_STATE_IDLE)) |
| qh_link_async (ehci, qh_get (qh)); |
| } |
| spin_unlock_irqrestore (&ehci->lock, flags); |
| if (unlikely (qh == NULL)) { |
| qtd_list_free (ehci, urb, qtd_list); |
| return -ENOMEM; |
| } |
| return 0; |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* the async qh for the qtds being reclaimed are now unlinked from the HC */ |
| |
| static void end_unlink_async (struct ehci_hcd *ehci, struct pt_regs *regs) |
| { |
| struct ehci_qh *qh = ehci->reclaim; |
| struct ehci_qh *next; |
| |
| timer_action_done (ehci, TIMER_IAA_WATCHDOG); |
| |
| // qh->hw_next = cpu_to_le32 (qh->qh_dma); |
| qh->qh_state = QH_STATE_IDLE; |
| qh->qh_next.qh = NULL; |
| qh_put (qh); // refcount from reclaim |
| |
| /* other unlink(s) may be pending (in QH_STATE_UNLINK_WAIT) */ |
| next = qh->reclaim; |
| ehci->reclaim = next; |
| ehci->reclaim_ready = 0; |
| qh->reclaim = NULL; |
| |
| qh_completions (ehci, qh, regs); |
| |
| if (!list_empty (&qh->qtd_list) |
| && HC_IS_RUNNING (ehci_to_hcd(ehci)->state)) |
| qh_link_async (ehci, qh); |
| else { |
| qh_put (qh); // refcount from async list |
| |
| /* it's not free to turn the async schedule on/off; leave it |
| * active but idle for a while once it empties. |
| */ |
| if (HC_IS_RUNNING (ehci_to_hcd(ehci)->state) |
| && ehci->async->qh_next.qh == NULL) |
| timer_action (ehci, TIMER_ASYNC_OFF); |
| } |
| |
| if (next) { |
| ehci->reclaim = NULL; |
| start_unlink_async (ehci, next); |
| } |
| } |
| |
| /* makes sure the async qh will become idle */ |
| /* caller must own ehci->lock */ |
| |
| static void start_unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh) |
| { |
| int cmd = readl (&ehci->regs->command); |
| struct ehci_qh *prev; |
| |
| #ifdef DEBUG |
| assert_spin_locked(&ehci->lock); |
| if (ehci->reclaim |
| || (qh->qh_state != QH_STATE_LINKED |
| && qh->qh_state != QH_STATE_UNLINK_WAIT) |
| ) |
| BUG (); |
| #endif |
| |
| /* stop async schedule right now? */ |
| if (unlikely (qh == ehci->async)) { |
| /* can't get here without STS_ASS set */ |
| if (ehci_to_hcd(ehci)->state != HC_STATE_HALT) { |
| writel (cmd & ~CMD_ASE, &ehci->regs->command); |
| wmb (); |
| // handshake later, if we need to |
| } |
| timer_action_done (ehci, TIMER_ASYNC_OFF); |
| return; |
| } |
| |
| qh->qh_state = QH_STATE_UNLINK; |
| ehci->reclaim = qh = qh_get (qh); |
| |
| prev = ehci->async; |
| while (prev->qh_next.qh != qh) |
| prev = prev->qh_next.qh; |
| |
| prev->hw_next = qh->hw_next; |
| prev->qh_next = qh->qh_next; |
| wmb (); |
| |
| if (unlikely (ehci_to_hcd(ehci)->state == HC_STATE_HALT)) { |
| /* if (unlikely (qh->reclaim != 0)) |
| * this will recurse, probably not much |
| */ |
| end_unlink_async (ehci, NULL); |
| return; |
| } |
| |
| ehci->reclaim_ready = 0; |
| cmd |= CMD_IAAD; |
| writel (cmd, &ehci->regs->command); |
| (void) readl (&ehci->regs->command); |
| timer_action (ehci, TIMER_IAA_WATCHDOG); |
| } |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| static void |
| scan_async (struct ehci_hcd *ehci, struct pt_regs *regs) |
| { |
| struct ehci_qh *qh; |
| enum ehci_timer_action action = TIMER_IO_WATCHDOG; |
| |
| if (!++(ehci->stamp)) |
| ehci->stamp++; |
| timer_action_done (ehci, TIMER_ASYNC_SHRINK); |
| rescan: |
| qh = ehci->async->qh_next.qh; |
| if (likely (qh != NULL)) { |
| do { |
| /* clean any finished work for this qh */ |
| if (!list_empty (&qh->qtd_list) |
| && qh->stamp != ehci->stamp) { |
| int temp; |
| |
| /* unlinks could happen here; completion |
| * reporting drops the lock. rescan using |
| * the latest schedule, but don't rescan |
| * qhs we already finished (no looping). |
| */ |
| qh = qh_get (qh); |
| qh->stamp = ehci->stamp; |
| temp = qh_completions (ehci, qh, regs); |
| qh_put (qh); |
| if (temp != 0) { |
| goto rescan; |
| } |
| } |
| |
| /* unlink idle entries, reducing HC PCI usage as well |
| * as HCD schedule-scanning costs. delay for any qh |
| * we just scanned, there's a not-unusual case that it |
| * doesn't stay idle for long. |
| * (plus, avoids some kind of re-activation race.) |
| */ |
| if (list_empty (&qh->qtd_list)) { |
| if (qh->stamp == ehci->stamp) |
| action = TIMER_ASYNC_SHRINK; |
| else if (!ehci->reclaim |
| && qh->qh_state == QH_STATE_LINKED) |
| start_unlink_async (ehci, qh); |
| } |
| |
| qh = qh->qh_next.qh; |
| } while (qh); |
| } |
| if (action == TIMER_ASYNC_SHRINK) |
| timer_action (ehci, TIMER_ASYNC_SHRINK); |
| } |