Spidernet Memory barrier

Add memory barrier to make sure that the rest of the
RX descriptor state is flushed to memory before we tell
the hardware that its ready to go.

Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Cc: James K Lewis <jklewis@us.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/net/spider_net.c b/drivers/net/spider_net.c
index 67bbd7ba406d..3bf4b9b6662a 100644
--- a/drivers/net/spider_net.c
+++ b/drivers/net/spider_net.c
@@ -419,6 +419,7 @@ spider_net_prepare_rx_descr(struct spider_net_card *card,
                 card->spider_stats.rx_iommu_map_error++;
                 descr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
         } else {
+                wmb();
                 descr->dmac_cmd_status = SPIDER_NET_DESCR_CARDOWNED |
                                          SPIDER_NET_DMAC_NOINTR_COMPLETE;
         }