IB/ipath: More changes to support InfiniPath on PowerPC 970 systems

Ordering of writethrough store buffers needs to be forced, and we need
to use ifdef to get writethrough behavior to InfiniPath buffers, because
there is no generic way to specify that at this time (similar to code
in char/drm/drm_vm.c and block/z2ram.c).

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

drivers/infiniband/hw/ipath/ipath_driver.c

@@ -440,7 +440,13 @@ static int __devinit ipath_init_one(struct pci_dev *pdev,
 	}
 	dd->ipath_pcirev = rev;
 
+#if defined(__powerpc__)
+	/* There isn't a generic way to specify writethrough mappings */
+	dd->ipath_kregbase = __ioremap(addr, len,
+		(_PAGE_NO_CACHE|_PAGE_WRITETHRU));
+#else
 	dd->ipath_kregbase = ioremap_nocache(addr, len);
+#endif
 
 	if (!dd->ipath_kregbase) {
 		ipath_dbg("Unable to map io addr %llx to kvirt, failing\n",