Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
---
drivers/usb/host/xhci-ring.c | 95 +++++++++++++++-----------------------------
1 file changed, 31 insertions(+), 64 deletions(-)
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 749fc68..35da18c 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -364,32 +364,6 @@ static void ring_doorbell_for_active_rings(struct xhci_hcd *xhci,
}
}
-/*
- * Find the segment that trb is in. Start searching in start_seg.
- * If we must move past a segment that has a link TRB with a toggle cycle state
- * bit set, then we will toggle the value pointed at by cycle_state.
- */
-static struct xhci_segment *find_trb_seg(
- struct xhci_segment *start_seg,
- union xhci_trb *trb, int *cycle_state)
-{
- struct xhci_segment *cur_seg = start_seg;
- struct xhci_generic_trb *generic_trb;
-
- while (cur_seg->trbs > trb ||
- &cur_seg->trbs[TRBS_PER_SEGMENT - 1] < trb) {
- generic_trb = &cur_seg->trbs[TRBS_PER_SEGMENT - 1].generic;
- if (generic_trb->field[3] & cpu_to_le32(LINK_TOGGLE))
- *cycle_state ^= 0x1;
- cur_seg = cur_seg->next;
- if (cur_seg == start_seg)
- /* Looped over the entire list. Oops! */
- return NULL;
- }
- return cur_seg;
-}
-
-
static struct xhci_ring *xhci_triad_to_transfer_ring(struct xhci_hcd *xhci,
unsigned int slot_id, unsigned int ep_index,
unsigned int stream_id)
@@ -459,9 +433,11 @@ void xhci_find_new_dequeue_state(struct xhci_hcd *xhci,
struct xhci_virt_device *dev = xhci->devs[slot_id];
struct xhci_virt_ep *ep = &dev->eps[ep_index];
struct xhci_ring *ep_ring;
- struct xhci_generic_trb *trb;
+ struct xhci_segment *new_seg;
+ union xhci_trb *new_deq, *tmp_trb;
dma_addr_t addr;
u64 hw_dequeue;
+ bool cycle_found = false;
ep_ring = xhci_triad_to_transfer_ring(xhci, slot_id,
ep_index, stream_id);
@@ -486,45 +462,36 @@ void xhci_find_new_dequeue_state(struct xhci_hcd *xhci,
hw_dequeue = le64_to_cpu(ep_ctx->deq);
}
- /* Find virtual address and segment of hardware dequeue pointer */
- state->new_deq_seg = ep_ring->deq_seg;
- state->new_deq_ptr = ep_ring->dequeue;
- while (xhci_trb_virt_to_dma(state->new_deq_seg, state->new_deq_ptr)
- != (dma_addr_t)(hw_dequeue & ~0xf)) {
- next_trb(xhci, ep_ring, &state->new_deq_seg,
- &state->new_deq_ptr);
- if (state->new_deq_ptr == ep_ring->dequeue) {
- WARN_ON(1);
- return;
- }
- }
+ new_seg = ep_ring->deq_seg;
+ new_deq = ep_ring->dequeue;
+ state->new_cycle_state = hw_dequeue & 0x1;
/*
- * Find cycle state for last_trb, starting at old cycle state of
- * hw_dequeue. If there is only one segment ring, find_trb_seg() will
- * return immediately and cannot toggle the cycle state if this search
- * wraps around, so add one more toggle manually in that case.
+ * We want to find the pointer, segment and cycle state of the
+ * new trb (the one after current TD's last_trb). We know the
+ * cycle state at hw_dequeue, so walk the ring until it's found.
+ * Once found we can jump a whole segments, but carefully cross them
+ * to check for cycle toggles.
*/
- state->new_cycle_state = hw_dequeue & 0x1;
- if (ep_ring->first_seg == ep_ring->first_seg->next &&
- cur_td->last_trb < state->new_deq_ptr)
- state->new_cycle_state ^= 0x1;
-
- state->new_deq_ptr = cur_td->last_trb;
- xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
- "Finding segment containing last TRB in TD.");
- state->new_deq_seg = find_trb_seg(state->new_deq_seg,
- state->new_deq_ptr, &state->new_cycle_state);
- if (!state->new_deq_seg) {
- WARN_ON(1);
- return;
- }
-
- /* Increment to find next TRB after last_trb. Cycle if appropriate. */
- trb = &state->new_deq_ptr->generic;
- if (TRB_TYPE_LINK_LE32(trb->field[3]) &&
- (trb->field[3] & cpu_to_le32(LINK_TOGGLE)))
- state->new_cycle_state ^= 0x1;
- next_trb(xhci, ep_ring, &state->new_deq_seg, &state->new_deq_ptr);
+ do {
+ if (cycle_found) {
+ if (new_seg->trbs > cur_td->last_trb ||
+ &new_seg->trbs[TRBS_PER_SEGMENT - 1] < cur_td->last_trb)
+ new_deq = &new_seg->trbs[TRBS_PER_SEGMENT - 1];
+ } else if (xhci_trb_virt_to_dma(new_seg, new_deq)
+ == (dma_addr_t)(hw_dequeue & ~0xf))
+ cycle_found = true;
+ tmp_trb = new_deq;
+ next_trb(xhci, ep_ring, &new_seg, &new_deq);
+
+ if (cycle_found &&
+ TRB_TYPE_LINK_LE32(tmp_trb->generic.field[3]) &&
+ tmp_trb->generic.field[3] & cpu_to_le32(LINK_TOGGLE))
+ state->new_cycle_state ^= 0x1;
+
+ } while (tmp_trb != cur_td->last_trb && new_deq != ep->ring->dequeue);
+
+ state->new_deq_seg = new_seg;
+ state->new_deq_ptr = new_deq;
/* Don't update the ring cycle state for the producer (us). */
xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
--
1.8.3.2
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