commit 569b87b47f906d65ee35d6ecc4767f20a6390b9b
author Arthur Jones <arthur.jones@qlogic.com> Thu Mar 15 14:45:05 2007 -0700
committer Roland Dreier <rolandd@cisco.com> Wed Apr 18 20:20:58 2007 -0700
tree d674574d3db6b25fe6bb41da8c64e1641bcc0d03
parent 7b196e2ff3953063b656212ff517f6115a1477b2

IB/ipath: Force PIOAvail update entry point

Due to a chip bug, the PIOAvail register is not always updated to
memory.  This patch allows userspace to force an update.

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

drivers/infiniband/hw/ipath/ipath_file_ops.c

diff --git a/drivers/infiniband/hw/ipath/ipath_file_ops.c b/drivers/infiniband/hw/ipath/ipath_file_ops.c
index bb53bde..9ca582b 100644
--- a/drivers/infiniband/hw/ipath/ipath_file_ops.c
+++ b/drivers/infiniband/hw/ipath/ipath_file_ops.c
@@ -2047,6 +2047,17 @@
 	return ret;
 }
 
+static int ipath_force_pio_avail_update(struct ipath_devdata *dd)
+{
+	u64 reg = dd->ipath_sendctrl;
+
+	clear_bit(IPATH_S_PIOBUFAVAILUPD, &reg);
+	ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl, reg);
+	ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl, dd->ipath_sendctrl);
+
+	return 0;
+}
+
 static ssize_t ipath_write(struct file *fp, const char __user *data,
 			   size_t count, loff_t *off)
 {
@@ -2106,22 +2117,30 @@
 		dest = &cmd.cmd.slave_mask_addr;
 		src = &ucmd->cmd.slave_mask_addr;
 		break;
+	case IPATH_CMD_PIOAVAILUPD:	// force an update of PIOAvail reg
+		copy = 0;
+		src = NULL;
+		dest = NULL;
+		break;
 	default:
 		ret = -EINVAL;
 		goto bail;
 	}
 
-	if ((count - consumed) < copy) {
-		ret = -EINVAL;
-		goto bail;
+	if (copy) {
+		if ((count - consumed) < copy) {
+			ret = -EINVAL;
+			goto bail;
+		}
+
+		if (copy_from_user(dest, src, copy)) {
+			ret = -EFAULT;
+			goto bail;
+		}
+
+		consumed += copy;
 	}
 
-	if (copy_from_user(dest, src, copy)) {
-		ret = -EFAULT;
-		goto bail;
-	}
-
-	consumed += copy;
 	pd = port_fp(fp);
 	if (!pd && cmd.type != __IPATH_CMD_USER_INIT &&
 		cmd.type != IPATH_CMD_ASSIGN_PORT) {
@@ -2172,6 +2191,9 @@
 					   (void __user *) (unsigned long)
 					   cmd.cmd.slave_mask_addr);
 		break;
+	case IPATH_CMD_PIOAVAILUPD:
+		ret = ipath_force_pio_avail_update(pd->port_dd);
+		break;
 	}
 
 	if (ret >= 0)