#define CAN_SCHEDULE_FRAMES 1000 /* how far in the future frames
* can be scheduled */
+/* When no queues need Full-Speed Bandwidth Reclamation,
+ * delay this long before turning FSBR off */
+#define FSBR_OFF_DELAY msecs_to_jiffies(400)
+
+/* If a queue hasn't advanced after this much time, assume it is stuck */
+#define QH_WAIT_TIMEOUT msecs_to_jiffies(200)
+
/*
* Queue Headers
struct uhci_td *dummy_td; /* Dummy TD to end the queue */
struct uhci_td *post_td; /* Last TD completed */
+ unsigned long advance_jiffies; /* Time of last queue advance */
unsigned int unlink_frame; /* When the QH was unlinked */
int state; /* QH_STATE_xxx; see above */
int type; /* Queue type (control, bulk, etc) */
unsigned int initial_toggle:1; /* Endpoint's current toggle value */
unsigned int needs_fixup:1; /* Must fix the TD toggle values */
unsigned int is_stopped:1; /* Queue was stopped by error/unlink */
+ unsigned int wait_expired:1; /* QH_WAIT_TIMEOUT has expired */
} __attribute__((aligned(16)));
/*
__le32 *frame;
void **frame_cpu; /* CPU's frame list */
- int fsbr; /* Full-speed bandwidth reclamation */
- unsigned long fsbrtimeout; /* FSBR delay */
+ unsigned long fsbr_jiffies; /* Time when FSBR was last wanted */
enum uhci_rh_state rh_state;
unsigned long auto_stop_time; /* When to AUTO_STOP */
unsigned int working_RD:1; /* Suspended root hub doesn't
need to be polled */
unsigned int is_initialized:1; /* Data structure is usable */
+ unsigned int fsbr_is_on:1; /* FSBR is turned on */
/* Support for port suspend/resume/reset */
unsigned long port_c_suspend; /* Bit-arrays of ports */
struct uhci_qh *qh; /* QH for this URB */
struct list_head td_list;
- unsigned fsbr : 1; /* URB turned on FSBR */
+ unsigned fsbr:1; /* URB wants FSBR */
};
uhci->term_td->status &= ~cpu_to_le32(TD_CTRL_IOC);
}
+
+/*
+ * Full-Speed Bandwidth Reclamation (FSBR).
+ * We turn on FSBR whenever a queue that wants it is advancing,
+ * and leave it on for a short time thereafter.
+ */
+static void uhci_fsbr_on(struct uhci_hcd *uhci)
+{
+ uhci->fsbr_is_on = 1;
+ uhci->skel_term_qh->link = cpu_to_le32(
+ uhci->skel_fs_control_qh->dma_handle) | UHCI_PTR_QH;
+}
+
+static void uhci_fsbr_off(struct uhci_hcd *uhci)
+{
+ uhci->fsbr_is_on = 0;
+ uhci->skel_term_qh->link = UHCI_PTR_TERM;
+}
+
+static void uhci_add_fsbr(struct uhci_hcd *uhci, struct urb *urb)
+{
+ struct urb_priv *urbp = urb->hcpriv;
+
+ if (!(urb->transfer_flags & URB_NO_FSBR))
+ urbp->fsbr = 1;
+}
+
+static void uhci_qh_wants_fsbr(struct uhci_hcd *uhci, struct uhci_qh *qh)
+{
+ struct urb_priv *urbp =
+ list_entry(qh->queue.next, struct urb_priv, node);
+
+ if (urbp->fsbr) {
+ uhci->fsbr_jiffies = jiffies;
+ if (!uhci->fsbr_is_on)
+ uhci_fsbr_on(uhci);
+ }
+}
+
+
static struct uhci_td *uhci_alloc_td(struct uhci_hcd *uhci)
{
dma_addr_t dma_handle;
qh->element = cpu_to_le32(td->dma_handle);
}
+ /* Treat the queue as if it has just advanced */
+ qh->wait_expired = 0;
+ qh->advance_jiffies = jiffies;
+
if (qh->state == QH_STATE_ACTIVE)
return;
qh->state = QH_STATE_ACTIVE;
kmem_cache_free(uhci_up_cachep, urbp);
}
-static void uhci_inc_fsbr(struct uhci_hcd *uhci, struct urb *urb)
-{
- struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
-
- if ((!(urb->transfer_flags & URB_NO_FSBR)) && !urbp->fsbr) {
- urbp->fsbr = 1;
- if (!uhci->fsbr++ && !uhci->fsbrtimeout)
- uhci->skel_term_qh->link = cpu_to_le32(uhci->skel_fs_control_qh->dma_handle) | UHCI_PTR_QH;
- }
-}
-
-static void uhci_dec_fsbr(struct uhci_hcd *uhci, struct urb *urb)
-{
- struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
-
- if ((!(urb->transfer_flags & URB_NO_FSBR)) && urbp->fsbr) {
- urbp->fsbr = 0;
- if (!--uhci->fsbr)
- uhci->fsbrtimeout = jiffies + FSBR_DELAY;
- }
-}
-
/*
* Map status to standard result codes
*
qh->skel = uhci->skel_ls_control_qh;
else {
qh->skel = uhci->skel_fs_control_qh;
- uhci_inc_fsbr(uhci, urb);
+ uhci_add_fsbr(uhci, urb);
}
urb->actual_length = -8; /* Account for the SETUP packet */
qh->skel = uhci->skel_bulk_qh;
ret = uhci_submit_common(uhci, urb, qh);
if (ret == 0)
- uhci_inc_fsbr(uhci, urb);
+ uhci_add_fsbr(uhci, urb);
return ret;
}
* the QH is new and idle or else it's unlinked and waiting to
* become idle, so we can activate it right away. But only if the
* queue isn't stopped. */
- if (qh->queue.next == &urbp->node && !qh->is_stopped)
+ if (qh->queue.next == &urbp->node && !qh->is_stopped) {
uhci_activate_qh(uhci, qh);
+ uhci_qh_wants_fsbr(uhci, qh);
+ }
goto done;
err_submit_failed:
qh->needs_fixup = 0;
}
- uhci_dec_fsbr(uhci, urb); /* Safe since it checks */
uhci_free_urb_priv(uhci, urbp);
switch (qh->type) {
if (!list_empty(&qh->queue)) {
if (qh->needs_fixup)
uhci_fixup_toggles(qh, 0);
+
+ /* If the first URB on the queue wants FSBR but its time
+ * limit has expired, set the next TD to interrupt on
+ * completion before reactivating the QH. */
+ urbp = list_entry(qh->queue.next, struct urb_priv, node);
+ if (urbp->fsbr && qh->wait_expired) {
+ struct uhci_td *td = list_entry(urbp->td_list.next,
+ struct uhci_td, list);
+
+ td->status |= __cpu_to_le32(TD_CTRL_IOC);
+ }
+
uhci_activate_qh(uhci, qh);
}
uhci_make_qh_idle(uhci, qh);
}
+/*
+ * Check for queues that have made some forward progress.
+ * Returns 0 if the queue is not Isochronous, is ACTIVE, and
+ * has not advanced since last examined; 1 otherwise.
+ */
+static int uhci_advance_check(struct uhci_hcd *uhci, struct uhci_qh *qh)
+{
+ struct urb_priv *urbp = NULL;
+ struct uhci_td *td;
+ int ret = 1;
+ unsigned status;
+
+ if (qh->type == USB_ENDPOINT_XFER_ISOC)
+ return ret;
+
+ /* Treat an UNLINKING queue as though it hasn't advanced.
+ * This is okay because reactivation will treat it as though
+ * it has advanced, and if it is going to become IDLE then
+ * this doesn't matter anyway. Furthermore it's possible
+ * for an UNLINKING queue not to have any URBs at all, or
+ * for its first URB not to have any TDs (if it was dequeued
+ * just as it completed). So it's not easy in any case to
+ * test whether such queues have advanced. */
+ if (qh->state != QH_STATE_ACTIVE) {
+ urbp = NULL;
+ status = 0;
+
+ } else {
+ urbp = list_entry(qh->queue.next, struct urb_priv, node);
+ td = list_entry(urbp->td_list.next, struct uhci_td, list);
+ status = td_status(td);
+ if (!(status & TD_CTRL_ACTIVE)) {
+
+ /* We're okay, the queue has advanced */
+ qh->wait_expired = 0;
+ qh->advance_jiffies = jiffies;
+ return ret;
+ }
+ ret = 0;
+ }
+
+ /* The queue hasn't advanced; check for timeout */
+ if (!qh->wait_expired && time_after(jiffies,
+ qh->advance_jiffies + QH_WAIT_TIMEOUT)) {
+ qh->wait_expired = 1;
+
+ /* If the current URB wants FSBR, unlink it temporarily
+ * so that we can safely set the next TD to interrupt on
+ * completion. That way we'll know as soon as the queue
+ * starts moving again. */
+ if (urbp && urbp->fsbr && !(status & TD_CTRL_IOC))
+ uhci_unlink_qh(uhci, qh);
+ }
+ return ret;
+}
+
/*
* Process events in the schedule, but only in one thread at a time
*/
return;
}
uhci->scan_in_progress = 1;
- rescan:
+rescan:
uhci->need_rescan = 0;
uhci_clear_next_interrupt(uhci);
while ((qh = uhci->next_qh) != uhci->skelqh[i]) {
uhci->next_qh = list_entry(qh->node.next,
struct uhci_qh, node);
- uhci_scan_qh(uhci, qh, regs);
+
+ if (uhci_advance_check(uhci, qh)) {
+ uhci_scan_qh(uhci, qh, regs);
+ if (qh->state == QH_STATE_ACTIVE)
+ uhci_qh_wants_fsbr(uhci, qh);
+ }
}
}
goto rescan;
uhci->scan_in_progress = 0;
+ if (uhci->fsbr_is_on && time_after(jiffies,
+ uhci->fsbr_jiffies + FSBR_OFF_DELAY))
+ uhci_fsbr_off(uhci);
+
if (list_empty(&uhci->skel_unlink_qh->node))
uhci_clear_next_interrupt(uhci);
else
uhci_set_next_interrupt(uhci);
}
-
-static void check_fsbr(struct uhci_hcd *uhci)
-{
- /* For now, don't scan URBs for FSBR timeouts.
- * Add it back in later... */
-
- /* Really disable FSBR */
- if (!uhci->fsbr && uhci->fsbrtimeout && time_after_eq(jiffies, uhci->fsbrtimeout)) {
- uhci->fsbrtimeout = 0;
- uhci->skel_term_qh->link = UHCI_PTR_TERM;
- }
-}
projects / linux-2.6 / commitdiff