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-rw-r--r--drivers/usb/host/xhci-mem.c1
-rw-r--r--drivers/usb/host/xhci-ring.c75
-rw-r--r--drivers/usb/host/xhci-trace.h5
-rw-r--r--drivers/usb/host/xhci.h3
4 files changed, 35 insertions, 49 deletions
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index c6f3ef2334a3..a8e9a4bb1537 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -143,7 +143,6 @@ static void xhci_link_rings(struct xhci_hcd *xhci, struct xhci_ring *ring,
xhci_link_segments(ring->enq_seg, first, ring->type, chain_links);
xhci_link_segments(last, next, ring->type, chain_links);
ring->num_segs += num_segs;
- ring->num_trbs_free += (TRBS_PER_SEGMENT - 1) * num_segs;
if (ring->type != TYPE_EVENT && ring->enq_seg == ring->last_seg) {
ring->last_seg->trbs[TRBS_PER_SEGMENT-1].link.control
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 2722dca6218e..646ff125def5 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -174,12 +174,10 @@ void inc_deq(struct xhci_hcd *xhci, struct xhci_ring *ring)
/* All other rings have link trbs */
if (!trb_is_link(ring->dequeue)) {
- if (last_trb_on_seg(ring->deq_seg, ring->dequeue)) {
+ if (last_trb_on_seg(ring->deq_seg, ring->dequeue))
xhci_warn(xhci, "Missing link TRB at end of segment\n");
- } else {
+ else
ring->dequeue++;
- ring->num_trbs_free++;
- }
}
while (trb_is_link(ring->dequeue)) {
@@ -221,9 +219,6 @@ static void inc_enq(struct xhci_hcd *xhci, struct xhci_ring *ring,
unsigned int link_trb_count = 0;
chain = le32_to_cpu(ring->enqueue->generic.field[3]) & TRB_CHAIN;
- /* If this is not event ring, there is one less usable TRB */
- if (!trb_is_link(ring->enqueue))
- ring->num_trbs_free--;
if (last_trb_on_seg(ring->enq_seg, ring->enqueue)) {
xhci_err(xhci, "Tried to move enqueue past ring segment\n");
@@ -276,24 +271,40 @@ static void inc_enq(struct xhci_hcd *xhci, struct xhci_ring *ring,
trace_xhci_inc_enq(ring);
}
-static int xhci_num_trbs_to(struct xhci_segment *start_seg, union xhci_trb *start,
- struct xhci_segment *end_seg, union xhci_trb *end,
- unsigned int num_segs)
+/*
+ * Return number of free normal TRBs from enqueue to dequeue pointer on ring.
+ * Not counting an assumed link TRB at end of each TRBS_PER_SEGMENT sized segment.
+ * Only for transfer and command rings where driver is the producer, not for
+ * event rings.
+ */
+static unsigned int xhci_num_trbs_free(struct xhci_hcd *xhci, struct xhci_ring *ring)
{
+ struct xhci_segment *enq_seg = ring->enq_seg;
+ union xhci_trb *enq = ring->enqueue;
union xhci_trb *last_on_seg;
- int num = 0;
+ unsigned int free = 0;
int i = 0;
+ /* Ring might be empty even if enq != deq if enq is left on a link trb */
+ if (trb_is_link(enq)) {
+ enq_seg = enq_seg->next;
+ enq = enq_seg->trbs;
+ }
+
+ /* Empty ring, common case, don't walk the segments */
+ if (enq == ring->dequeue)
+ return ring->num_segs * (TRBS_PER_SEGMENT - 1);
+
do {
- if (start_seg == end_seg && end >= start)
- return num + (end - start);
- last_on_seg = &start_seg->trbs[TRBS_PER_SEGMENT - 1];
- num += last_on_seg - start;
- start_seg = start_seg->next;
- start = start_seg->trbs;
- } while (i++ <= num_segs);
-
- return -EINVAL;
+ if (ring->deq_seg == enq_seg && ring->dequeue >= enq)
+ return free + (ring->dequeue - enq);
+ last_on_seg = &enq_seg->trbs[TRBS_PER_SEGMENT - 1];
+ free += last_on_seg - enq;
+ enq_seg = enq_seg->next;
+ enq = enq_seg->trbs;
+ } while (i++ <= ring->num_segs);
+
+ return free;
}
/*
@@ -1291,10 +1302,7 @@ static void update_ring_for_set_deq_completion(struct xhci_hcd *xhci,
unsigned int ep_index)
{
union xhci_trb *dequeue_temp;
- int num_trbs_free_temp;
- bool revert = false;
- num_trbs_free_temp = ep_ring->num_trbs_free;
dequeue_temp = ep_ring->dequeue;
/* If we get two back-to-back stalls, and the first stalled transfer
@@ -1310,7 +1318,6 @@ static void update_ring_for_set_deq_completion(struct xhci_hcd *xhci,
while (ep_ring->dequeue != dev->eps[ep_index].queued_deq_ptr) {
/* We have more usable TRBs */
- ep_ring->num_trbs_free++;
ep_ring->dequeue++;
if (trb_is_link(ep_ring->dequeue)) {
if (ep_ring->dequeue ==
@@ -1320,15 +1327,10 @@ static void update_ring_for_set_deq_completion(struct xhci_hcd *xhci,
ep_ring->dequeue = ep_ring->deq_seg->trbs;
}
if (ep_ring->dequeue == dequeue_temp) {
- revert = true;
+ xhci_dbg(xhci, "Unable to find new dequeue pointer\n");
break;
}
}
-
- if (revert) {
- xhci_dbg(xhci, "Unable to find new dequeue pointer\n");
- ep_ring->num_trbs_free = num_trbs_free_temp;
- }
}
/*
@@ -2183,7 +2185,6 @@ static int finish_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
u32 trb_comp_code)
{
struct xhci_ep_ctx *ep_ctx;
- int trbs_freed;
ep_ctx = xhci_get_ep_ctx(xhci, ep->vdev->out_ctx, ep->ep_index);
@@ -2253,13 +2254,6 @@ static int finish_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
}
/* Update ring dequeue pointer */
- trbs_freed = xhci_num_trbs_to(ep_ring->deq_seg, ep_ring->dequeue,
- td->last_trb_seg, td->last_trb,
- ep_ring->num_segs);
- if (trbs_freed < 0)
- xhci_dbg(xhci, "Failed to count freed trbs at TD finish\n");
- else
- ep_ring->num_trbs_free += trbs_freed;
ep_ring->dequeue = td->last_trb;
ep_ring->deq_seg = td->last_trb_seg;
inc_deq(xhci, ep_ring);
@@ -2483,7 +2477,6 @@ static int skip_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td,
/* Update ring dequeue pointer */
ep->ring->dequeue = td->last_trb;
ep->ring->deq_seg = td->last_trb_seg;
- ep->ring->num_trbs_free += td->num_trbs - 1;
inc_deq(xhci, ep->ring);
return xhci_td_cleanup(xhci, td, ep->ring, status);
@@ -3227,7 +3220,7 @@ static int prepare_ring(struct xhci_hcd *xhci, struct xhci_ring *ep_ring,
if (ep_ring != xhci->cmd_ring) {
new_segs = xhci_ring_expansion_needed(xhci, ep_ring, num_trbs);
- } else if (ep_ring->num_trbs_free <= num_trbs) {
+ } else if (xhci_num_trbs_free(xhci, ep_ring) <= num_trbs) {
xhci_err(xhci, "Do not support expand command ring\n");
return -ENOMEM;
}
@@ -4205,7 +4198,6 @@ cleanup:
ep_ring->enqueue = urb_priv->td[0].first_trb;
ep_ring->enq_seg = urb_priv->td[0].start_seg;
ep_ring->cycle_state = start_cycle;
- ep_ring->num_trbs_free = ep_ring->num_trbs_free_temp;
usb_hcd_unlink_urb_from_ep(bus_to_hcd(urb->dev->bus), urb);
return ret;
}
@@ -4287,7 +4279,6 @@ int xhci_queue_isoc_tx_prepare(struct xhci_hcd *xhci, gfp_t mem_flags,
}
skip_start_over:
- ep_ring->num_trbs_free_temp = ep_ring->num_trbs_free;
return xhci_queue_isoc_tx(xhci, mem_flags, urb, slot_id, ep_index);
}
diff --git a/drivers/usb/host/xhci-trace.h b/drivers/usb/host/xhci-trace.h
index 7555c4ea7c4b..d6b32f2ad90e 100644
--- a/drivers/usb/host/xhci-trace.h
+++ b/drivers/usb/host/xhci-trace.h
@@ -458,7 +458,6 @@ DECLARE_EVENT_CLASS(xhci_log_ring,
__field(unsigned int, num_segs)
__field(unsigned int, stream_id)
__field(unsigned int, cycle_state)
- __field(unsigned int, num_trbs_free)
__field(unsigned int, bounce_buf_len)
),
TP_fast_assign(
@@ -469,18 +468,16 @@ DECLARE_EVENT_CLASS(xhci_log_ring,
__entry->enq_seg = ring->enq_seg->dma;
__entry->deq_seg = ring->deq_seg->dma;
__entry->cycle_state = ring->cycle_state;
- __entry->num_trbs_free = ring->num_trbs_free;
__entry->bounce_buf_len = ring->bounce_buf_len;
__entry->enq = xhci_trb_virt_to_dma(ring->enq_seg, ring->enqueue);
__entry->deq = xhci_trb_virt_to_dma(ring->deq_seg, ring->dequeue);
),
- TP_printk("%s %p: enq %pad(%pad) deq %pad(%pad) segs %d stream %d free_trbs %d bounce %d cycle %d",
+ TP_printk("%s %p: enq %pad(%pad) deq %pad(%pad) segs %d stream %d bounce %d cycle %d",
xhci_ring_type_string(__entry->type), __entry->ring,
&__entry->enq, &__entry->enq_seg,
&__entry->deq, &__entry->deq_seg,
__entry->num_segs,
__entry->stream_id,
- __entry->num_trbs_free,
__entry->bounce_buf_len,
__entry->cycle_state
)
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 56e318c384ff..456e1c8ca005 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1633,8 +1633,7 @@ struct xhci_ring {
u32 cycle_state;
unsigned int stream_id;
unsigned int num_segs;
- unsigned int num_trbs_free;
- unsigned int num_trbs_free_temp;
+ unsigned int num_trbs_free; /* used only by xhci DbC */
unsigned int bounce_buf_len;
enum xhci_ring_type type;
bool last_td_was_short;