IB/ipath: Changes to support PIO bandwidth check on IBA7220

The IBA7220 uses a count-based triggering mechanism, and therefore
can't use the same bandwidth verification mechanism as older chips.

To support the 7220, allow enabling and disabling armlaunch errors on
application request.  Minor robustness improvements as well.
Signed-off-by: Dave Olson <dave.olson@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

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 */

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);

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)

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