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>

diff --git a/drivers/net/spider_net.c b/drivers/net/spider_net.c
index 67bbd7ba406d19cf3507a4434848f9ba3ec55632..3bf4b9b6662a838e13447ca923e3946dbc271cf3 100644 (file)
--- 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;
        }