IB/ipath: Add ability to set and clear IB local loopback

This is a sticky state.  It is useful for diagnosing problems with
boards versus cable/switch problems.

Signed-off-by: Dave Olson <dave.olson@qlogic.com>
Signed-off-by: Bryan O'Sullivan <bryan.osullivan@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

diff --git a/drivers/infiniband/hw/ipath/ipath_common.h b/drivers/infiniband/hw/ipath/ipath_common.h
index 54139d3..a413678 100644 (file)
--- a/drivers/infiniband/hw/ipath/ipath_common.h
+++ b/drivers/infiniband/hw/ipath/ipath_common.h
@@ -78,6 +78,8 @@
 #define IPATH_IB_LINKINIT              3
 #define IPATH_IB_LINKDOWN_SLEEP                4
 #define IPATH_IB_LINKDOWN_DISABLE      5
+#define IPATH_IB_LINK_LOOPBACK 6 /* enable local loopback */
+#define IPATH_IB_LINK_EXTERNAL 7 /* normal, disable local loopback */
 
 /*
  * stats maintained by the driver.  For now, at least, this is global

diff --git a/drivers/infiniband/hw/ipath/ipath_driver.c b/drivers/infiniband/hw/ipath/ipath_driver.c
index ae7f21a..c2fe541 100644 (file)
--- a/drivers/infiniband/hw/ipath/ipath_driver.c
+++ b/drivers/infiniband/hw/ipath/ipath_driver.c
@@ -1662,6 +1662,22 @@ int ipath_set_linkstate(struct ipath_devdata *dd, u8 newstate)
                lstate = IPATH_LINKACTIVE;
                break;
 
+       case IPATH_IB_LINK_LOOPBACK:
+               dev_info(&dd->pcidev->dev, "Enabling IB local loopback\n");
+               dd->ipath_ibcctrl |= INFINIPATH_IBCC_LOOPBACK;
+               ipath_write_kreg(dd, dd->ipath_kregs->kr_ibcctrl,
+                                dd->ipath_ibcctrl);
+               ret = 0;
+               goto bail; // no state change to wait for
+
+       case IPATH_IB_LINK_EXTERNAL:
+               dev_info(&dd->pcidev->dev, "Disabling IB local loopback (normal)\n");
+               dd->ipath_ibcctrl &= ~INFINIPATH_IBCC_LOOPBACK;
+               ipath_write_kreg(dd, dd->ipath_kregs->kr_ibcctrl,
+                                dd->ipath_ibcctrl);
+               ret = 0;
+               goto bail; // no state change to wait for
+
        default:
                ipath_dbg("Invalid linkstate 0x%x requested\n", newstate);
                ret = -EINVAL;