IB/qib: Don't mark VL15 bufs as WC to avoid a rare 7322 chip problem

Don't set write combining via PAT on the VL15 buffers to avoid a rare
problem with unaligned writes from interrupt-flushed store buffers.

Signed-off-by: Dave Olson <dave.olson@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/qib/qib_init.c b/drivers/infiniband/hw/qib/qib_init.c
index 9b40f345ac3..25895991dc5 100644
--- a/drivers/infiniband/hw/qib/qib_init.c
+++ b/drivers/infiniband/hw/qib/qib_init.c
@@ -1499,6 +1499,12 @@ bail:
         return -ENOMEM;
 }
 
+/*
+ * Note: Changes to this routine should be mirrored
+ * for the diagnostics routine qib_remap_ioaddr32().
+ * There is also related code for VL15 buffers in qib_init_7322_variables().
+ * The teardown code that unmaps is in qib_pcie_ddcleanup()
+ */
 int init_chip_wc_pat(struct qib_devdata *dd, u32 vl15buflen)
 {
         u64 __iomem *qib_kregbase = NULL;