diff options
Diffstat (limited to 'drivers/usb/host/ehci-sched.c')
| -rw-r--r-- | drivers/usb/host/ehci-sched.c | 136 |
1 files changed, 61 insertions, 75 deletions
diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c index 7cf3da7babf0..69ebee73c0c1 100644 --- a/drivers/usb/host/ehci-sched.c +++ b/drivers/usb/host/ehci-sched.c @@ -36,29 +36,6 @@ static int ehci_get_frame (struct usb_hcd *hcd); -#ifdef CONFIG_PCI - -static unsigned ehci_read_frame_index(struct ehci_hcd *ehci) -{ - unsigned uf; - - /* - * The MosChip MCS9990 controller updates its microframe counter - * a little before the frame counter, and occasionally we will read - * the invalid intermediate value. Avoid problems by checking the - * microframe number (the low-order 3 bits); if they are 0 then - * re-read the register to get the correct value. - */ - uf = ehci_readl(ehci, &ehci->regs->frame_index); - if (unlikely(ehci->frame_index_bug && ((uf & 7) == 0))) - uf = ehci_readl(ehci, &ehci->regs->frame_index); - return uf; -} - -#endif - -/*-------------------------------------------------------------------------*/ - /* * periodic_next_shadow - return "next" pointer on shadow list * @periodic: host pointer to qh/itd/sitd @@ -1361,7 +1338,7 @@ sitd_slot_ok ( * given EHCI_TUNE_FLS and the slop). Or, write a smarter scheduler! */ -#define SCHEDULE_SLOP 80 /* microframes */ +#define SCHEDULING_DELAY 40 /* microframes */ static int iso_stream_schedule ( @@ -1370,7 +1347,7 @@ iso_stream_schedule ( struct ehci_iso_stream *stream ) { - u32 now, next, start, period, span; + u32 now, base, next, start, period, span; int status; unsigned mod = ehci->periodic_size << 3; struct ehci_iso_sched *sched = urb->hcpriv; @@ -1382,62 +1359,72 @@ iso_stream_schedule ( span <<= 3; } - if (span > mod - SCHEDULE_SLOP) { - ehci_dbg (ehci, "iso request %p too long\n", urb); - status = -EFBIG; - goto fail; - } - now = ehci_read_frame_index(ehci) & (mod - 1); /* Typical case: reuse current schedule, stream is still active. * Hopefully there are no gaps from the host falling behind - * (irq delays etc), but if there are we'll take the next - * slot in the schedule, implicitly assuming URB_ISO_ASAP. + * (irq delays etc). If there are, the behavior depends on + * whether URB_ISO_ASAP is set. */ if (likely (!list_empty (&stream->td_list))) { - u32 excess; - /* For high speed devices, allow scheduling within the - * isochronous scheduling threshold. For full speed devices - * and Intel PCI-based controllers, don't (work around for - * Intel ICH9 bug). - */ - if (!stream->highspeed && ehci->fs_i_thresh) - next = now + ehci->i_thresh; + /* Take the isochronous scheduling threshold into account */ + if (ehci->i_thresh) + next = now + ehci->i_thresh; /* uframe cache */ else - next = now; + next = (now + 2 + 7) & ~0x07; /* full frame cache */ - /* Fell behind (by up to twice the slop amount)? - * We decide based on the time of the last currently-scheduled - * slot, not the time of the next available slot. + /* + * Use ehci->last_iso_frame as the base. There can't be any + * TDs scheduled for earlier than that. */ - excess = (stream->next_uframe - period - next) & (mod - 1); - if (excess >= mod - 2 * SCHEDULE_SLOP) - start = next + excess - mod + period * - DIV_ROUND_UP(mod - excess, period); - else - start = next + excess + period; - if (start - now >= mod) { - ehci_dbg(ehci, "request %p would overflow (%d+%d >= %d)\n", - urb, start - now - period, period, - mod); - status = -EFBIG; + base = ehci->last_iso_frame << 3; + next = (next - base) & (mod - 1); + start = (stream->next_uframe - base) & (mod - 1); + + /* Is the schedule already full? */ + if (unlikely(start < period)) { + ehci_dbg(ehci, "iso sched full %p (%u-%u < %u mod %u)\n", + urb, stream->next_uframe, base, + period, mod); + status = -ENOSPC; goto fail; } + + /* Behind the scheduling threshold? */ + if (unlikely(start < next)) { + + /* USB_ISO_ASAP: Round up to the first available slot */ + if (urb->transfer_flags & URB_ISO_ASAP) + start += (next - start + period - 1) & -period; + + /* + * Not ASAP: Use the next slot in the stream. If + * the entire URB falls before the threshold, fail. + */ + else if (start + span - period < next) { + ehci_dbg(ehci, "iso urb late %p (%u+%u < %u)\n", + urb, start + base, + span - period, next + base); + status = -EXDEV; + goto fail; + } + } + + start += base; } /* need to schedule; when's the next (u)frame we could start? * this is bigger than ehci->i_thresh allows; scheduling itself - * isn't free, the slop should handle reasonably slow cpus. it + * isn't free, the delay should handle reasonably slow cpus. it * can also help high bandwidth if the dma and irq loads don't * jump until after the queue is primed. */ else { int done = 0; - start = SCHEDULE_SLOP + (now & ~0x07); - /* NOTE: assumes URB_ISO_ASAP, to limit complexity/bugs */ + base = now & ~0x07; + start = base + SCHEDULING_DELAY; /* find a uframe slot with enough bandwidth. * Early uframes are more precious because full-speed @@ -1464,19 +1451,16 @@ iso_stream_schedule ( /* no room in the schedule */ if (!done) { - ehci_dbg(ehci, "iso resched full %p (now %d max %d)\n", - urb, now, now + mod); + ehci_dbg(ehci, "iso sched full %p", urb); status = -ENOSPC; goto fail; } } /* Tried to schedule too far into the future? */ - if (unlikely(start - now + span - period - >= mod - 2 * SCHEDULE_SLOP)) { - ehci_dbg(ehci, "request %p would overflow (%d+%d >= %d)\n", - urb, start - now, span - period, - mod - 2 * SCHEDULE_SLOP); + if (unlikely(start - base + span - period >= mod)) { + ehci_dbg(ehci, "request %p would overflow (%u+%u >= %u)\n", + urb, start - base, span - period, mod); status = -EFBIG; goto fail; } @@ -1490,7 +1474,7 @@ iso_stream_schedule ( /* Make sure scan_isoc() sees these */ if (ehci->isoc_count == 0) - ehci->next_frame = now >> 3; + ehci->last_iso_frame = now >> 3; return 0; fail: @@ -1646,7 +1630,7 @@ static void itd_link_urb( /* don't need that schedule data any more */ iso_sched_free (stream, iso_sched); - urb->hcpriv = NULL; + urb->hcpriv = stream; ++ehci->isoc_count; enable_periodic(ehci); @@ -1708,7 +1692,7 @@ static bool itd_complete(struct ehci_hcd *ehci, struct ehci_itd *itd) urb->actual_length += desc->actual_length; } else { /* URB was too late */ - desc->status = -EXDEV; + urb->error_count++; } } @@ -2045,7 +2029,7 @@ static void sitd_link_urb( /* don't need that schedule data any more */ iso_sched_free (stream, sched); - urb->hcpriv = NULL; + urb->hcpriv = stream; ++ehci->isoc_count; enable_periodic(ehci); @@ -2081,7 +2065,7 @@ static bool sitd_complete(struct ehci_hcd *ehci, struct ehci_sitd *sitd) t = hc32_to_cpup(ehci, &sitd->hw_results); /* report transfer status */ - if (t & SITD_ERRS) { + if (unlikely(t & SITD_ERRS)) { urb->error_count++; if (t & SITD_STS_DBE) desc->status = usb_pipein (urb->pipe) @@ -2091,6 +2075,9 @@ static bool sitd_complete(struct ehci_hcd *ehci, struct ehci_sitd *sitd) 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); @@ -2220,16 +2207,16 @@ static void scan_isoc(struct ehci_hcd *ehci) now_frame = (uf >> 3) & fmask; live = true; } else { - now_frame = (ehci->next_frame - 1) & fmask; + now_frame = (ehci->last_iso_frame - 1) & fmask; live = false; } ehci->now_frame = now_frame; - frame = ehci->next_frame; for (;;) { union ehci_shadow q, *q_p; __hc32 type, *hw_p; + frame = ehci->last_iso_frame; restart: /* scan each element in frame's queue for completions */ q_p = &ehci->pshadow [frame]; @@ -2334,7 +2321,6 @@ restart: /* Stop when we have reached the current frame */ if (frame == now_frame) break; - frame = (frame + 1) & fmask; + ehci->last_iso_frame = (frame + 1) & fmask; } - ehci->next_frame = now_frame; } |