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, 6 insertions, 15 deletions

diff --git a/drivers/infiniband/hw/ipath/ipath_iba7220.c b/drivers/infiniband/hw/ipath/ipath_iba7220.c
index 5f693de66542..8eee7830f042 100644
--- a/drivers/infiniband/hw/ipath/ipath_iba7220.c
+++ b/drivers/infiniband/hw/ipath/ipath_iba7220.c
@@ -595,7 +595,7 @@ static void ipath_7220_txe_recover(struct ipath_devdata *dd)
 
 	dev_info(&dd->pcidev->dev,
 		"Recovering from TXE PIO parity error\n");
-	ipath_disarm_senderrbufs(dd, 1);
+	ipath_disarm_senderrbufs(dd);
 }
 
 
@@ -675,10 +675,8 @@ static void ipath_7220_handle_hwerrors(struct ipath_devdata *dd, char *msg,
 	ctrl = ipath_read_kreg32(dd, dd->ipath_kregs->kr_control);
 	if ((ctrl & INFINIPATH_C_FREEZEMODE) && !ipath_diag_inuse) {
 		/*
-		 * Parity errors in send memory are recoverable,
-		 * just cancel the send (if indicated in * sendbuffererror),
-		 * count the occurrence, unfreeze (if no other handled
-		 * hardware error bits are set), and continue.
+		 * Parity errors in send memory are recoverable by h/w
+		 * just do housekeeping, exit freeze mode and continue.
 		 */
 		if (hwerrs & ((INFINIPATH_HWE_TXEMEMPARITYERR_PIOBUF |
 			       INFINIPATH_HWE_TXEMEMPARITYERR_PIOPBC)
@@ -687,13 +685,6 @@ static void ipath_7220_handle_hwerrors(struct ipath_devdata *dd, char *msg,
 			hwerrs &= ~((INFINIPATH_HWE_TXEMEMPARITYERR_PIOBUF |
 				     INFINIPATH_HWE_TXEMEMPARITYERR_PIOPBC)
 				    << INFINIPATH_HWE_TXEMEMPARITYERR_SHIFT);
-			if (!hwerrs) {
-				/* else leave in freeze mode */
-				ipath_write_kreg(dd,
-						 dd->ipath_kregs->kr_control,
-						 dd->ipath_control);
-				goto bail;
-			}
 		}
 		if (hwerrs) {
 			/*
@@ -723,8 +714,8 @@ static void ipath_7220_handle_hwerrors(struct ipath_devdata *dd, char *msg,
 			*dd->ipath_statusp |= IPATH_STATUS_HWERROR;
 			dd->ipath_flags &= ~IPATH_INITTED;
 		} else {
-			ipath_dbg("Clearing freezemode on ignored hardware "
-				  "error\n");
+			ipath_dbg("Clearing freezemode on ignored or "
+				"recovered hardware error\n");
 			ipath_clear_freeze(dd);
 		}
 	}
@@ -1967,7 +1958,7 @@ static void ipath_7220_config_ports(struct ipath_devdata *dd, ushort cfgports)
 			 dd->ipath_rcvctrl);
 	dd->ipath_p0_rcvegrcnt = 2048; /* always */
 	if (dd->ipath_flags & IPATH_HAS_SEND_DMA)
-		dd->ipath_pioreserved = 1; /* reserve a buffer */
+		dd->ipath_pioreserved = 3; /* kpiobufs used for PIO */
 }