IB/ipath: Need to always request and handle PIO avail interrupts

Now that we always use PIO for vl15 on 7220, we could get stuck forever
if we happened to run out of PIO buffers from the verbs code, because
the setup code wouldn't run; the interrupt was also ignored if SDMA was
supported.  We also have to reduce the pio update threshold if we have
fewer kernel buffers than the existing threshold.

Clean up the initialization a bit to get ordering safer and more
sensible, and use the existing ipath_chg_kernavail call to do init,
rather than doing it separately.

Drop unnecessary clearing of pio buffer on pio parity error.

Drop incorrect updating of pioavailshadow when exitting freeze mode
(software state may not match chip state if buffer has been allocated
and not yet written).

If we couldn't get a kernel buffer for a while, make sure we are
in sync with hardware, mainly to handle the exitting freeze case.

Signed-off-by: Dave Olson <dave.olson@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 4 insertions, 3 deletions

diff --git a/drivers/infiniband/hw/ipath/ipath_ruc.c b/drivers/infiniband/hw/ipath/ipath_ruc.c
index 8ac5c1d82ccd..9e3fe61cbd08 100644
--- a/drivers/infiniband/hw/ipath/ipath_ruc.c
+++ b/drivers/infiniband/hw/ipath/ipath_ruc.c
@@ -481,9 +481,10 @@ done:
 		wake_up(&qp->wait);
 }
 
-static void want_buffer(struct ipath_devdata *dd)
+static void want_buffer(struct ipath_devdata *dd, struct ipath_qp *qp)
 {
-	if (!(dd->ipath_flags & IPATH_HAS_SEND_DMA)) {
+	if (!(dd->ipath_flags & IPATH_HAS_SEND_DMA) ||
+		qp->ibqp.qp_type == IB_QPT_SMI) {
 		unsigned long flags;
 
 		spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
@@ -519,7 +520,7 @@ static void ipath_no_bufs_available(struct ipath_qp *qp,
 	spin_lock_irqsave(&dev->pending_lock, flags);
 	list_add_tail(&qp->piowait, &dev->piowait);
 	spin_unlock_irqrestore(&dev->pending_lock, flags);
-	want_buffer(dev->dd);
+	want_buffer(dev->dd, qp);
 	dev->n_piowait++;
 }