diff --git a/drivers/infiniband/hw/ipath/ipath_common.h b/drivers/infiniband/hw/ipath/ipath_common.h
index 0fa43ba25b7e..414621095540 100644
--- a/drivers/infiniband/hw/ipath/ipath_common.h
+++ b/drivers/infiniband/hw/ipath/ipath_common.h
@@ -443,8 +443,9 @@ struct ipath_user_info {
 #define IPATH_CMD_UNUSED_2	26
 #define IPATH_CMD_PIOAVAILUPD	27	/* force an update of PIOAvail reg */
 #define IPATH_CMD_POLL_TYPE	28	/* set the kind of polling we want */
+#define IPATH_CMD_ARMLAUNCH_CTRL	29 /* armlaunch detection control */
 
-#define IPATH_CMD_MAX		28
+#define IPATH_CMD_MAX		29
 
 /*
  * Poll types
@@ -487,6 +488,8 @@ struct ipath_cmd {
 		__u64 port_info;
 		/* enable/disable receipt of packets */
 		__u32 recv_ctrl;
+		/* enable/disable armlaunch errors (non-zero to enable) */
+		__u32 armlaunch_ctrl;
 		/* partition key to set */
 		__u16 part_key;
 		/* user address of __u32 bitmask of active slaves */
diff --git a/drivers/infiniband/hw/ipath/ipath_driver.c b/drivers/infiniband/hw/ipath/ipath_driver.c
index bfcdf8c254c5..d5ff6ca2db30 100644
--- a/drivers/infiniband/hw/ipath/ipath_driver.c
+++ b/drivers/infiniband/hw/ipath/ipath_driver.c
@@ -334,6 +334,8 @@ static void ipath_verify_pioperf(struct ipath_devdata *dd)
 		udelay(1);
 	}
 
+	ipath_disable_armlaunch(dd);
+
 	writeq(0, piobuf); /* length 0, no dwords actually sent */
 	ipath_flush_wc();
 
@@ -365,6 +367,7 @@ static void ipath_verify_pioperf(struct ipath_devdata *dd)
 done:
 	/* disarm piobuf, so it's available again */
 	ipath_disarm_piobufs(dd, pbnum, 1);
+	ipath_enable_armlaunch(dd);
 }
 
 static int __devinit ipath_init_one(struct pci_dev *pdev,
@@ -2271,5 +2274,34 @@ int ipath_set_rx_pol_inv(struct ipath_devdata *dd, u8 new_pol_inv)
 	}
 	return 0;
 }
+
+/*
+ * Disable and enable the armlaunch error.  Used for PIO bandwidth testing on
+ * the 7220, which is count-based, rather than trigger-based.  Safe for the
+ * driver check, since it's at init.   Not completely safe when used for
+ * user-mode checking, since some error checking can be lost, but not
+ * particularly risky, and only has problematic side-effects in the face of
+ * very buggy user code.  There is no reference counting, but that's also
+ * fine, given the intended use.
+ */
+void ipath_enable_armlaunch(struct ipath_devdata *dd)
+{
+	dd->ipath_lasterror &= ~INFINIPATH_E_SPIOARMLAUNCH;
+	ipath_write_kreg(dd, dd->ipath_kregs->kr_errorclear,
+		INFINIPATH_E_SPIOARMLAUNCH);
+	dd->ipath_errormask |= INFINIPATH_E_SPIOARMLAUNCH;
+	ipath_write_kreg(dd, dd->ipath_kregs->kr_errormask,
+		dd->ipath_errormask);
+}
+
+void ipath_disable_armlaunch(struct ipath_devdata *dd)
+{
+	/* so don't re-enable if already set */
+	dd->ipath_maskederrs &= ~INFINIPATH_E_SPIOARMLAUNCH;
+	dd->ipath_errormask &= ~INFINIPATH_E_SPIOARMLAUNCH;
+	ipath_write_kreg(dd, dd->ipath_kregs->kr_errormask,
+		dd->ipath_errormask);
+}
+
 module_init(infinipath_init);
 module_exit(infinipath_cleanup);
diff --git a/drivers/infiniband/hw/ipath/ipath_file_ops.c b/drivers/infiniband/hw/ipath/ipath_file_ops.c
index 7b2f59af9c91..7e025c8e01b6 100644
--- a/drivers/infiniband/hw/ipath/ipath_file_ops.c
+++ b/drivers/infiniband/hw/ipath/ipath_file_ops.c
@@ -2224,6 +2224,11 @@ static ssize_t ipath_write(struct file *fp, const char __user *data,
 		dest = &cmd.cmd.poll_type;
 		src = &ucmd->cmd.poll_type;
 		break;
+	case IPATH_CMD_ARMLAUNCH_CTRL:
+		copy = sizeof(cmd.cmd.armlaunch_ctrl);
+		dest = &cmd.cmd.armlaunch_ctrl;
+		src = &ucmd->cmd.armlaunch_ctrl;
+		break;
 	default:
 		ret = -EINVAL;
 		goto bail;
@@ -2299,6 +2304,12 @@ static ssize_t ipath_write(struct file *fp, const char __user *data,
 	case IPATH_CMD_POLL_TYPE:
 		pd->poll_type = cmd.cmd.poll_type;
 		break;
+	case IPATH_CMD_ARMLAUNCH_CTRL:
+		if (cmd.cmd.armlaunch_ctrl)
+			ipath_enable_armlaunch(pd->port_dd);
+		else
+			ipath_disable_armlaunch(pd->port_dd);
+		break;
 	}
 
 	if (ret >= 0)
diff --git a/drivers/infiniband/hw/ipath/ipath_kernel.h b/drivers/infiniband/hw/ipath/ipath_kernel.h
index 31d79e246aa0..4cc0f95ea877 100644
--- a/drivers/infiniband/hw/ipath/ipath_kernel.h
+++ b/drivers/infiniband/hw/ipath/ipath_kernel.h
@@ -771,6 +771,8 @@ int ipath_set_linkstate(struct ipath_devdata *, u8);
 int ipath_set_mtu(struct ipath_devdata *, u16);
 int ipath_set_lid(struct ipath_devdata *, u32, u8);
 int ipath_set_rx_pol_inv(struct ipath_devdata *dd, u8 new_pol_inv);
+void ipath_enable_armlaunch(struct ipath_devdata *);
+void ipath_disable_armlaunch(struct ipath_devdata *);
 
 /* for use in system calls, where we want to know device type, etc. */
 #define port_fp(fp) ((struct ipath_filedata *)(fp)->private_data)->pd