net: aquantia: fix potential IOMMU fault after driver unbind

IOMMU fault may occurr on unbind/bind or if_down/if_up sequence.

Although driver disables the rings on down, this is not enough.
Due to internal HW design, during subsequent initialization
NIC sometimes may reuse RX descriptors cache and write to the
host memory from the descriptor cache.
That's get catched by IOMMU on host.

This patch invalidates the descriptor cache in NIC on interface down
to prevent writing to the cached descriptors and to the memory pointed
in those descriptors.

Signed-off-by: Dmitry Bogdanov <dmitry.bogdanov@aquantia.com>
Signed-off-by: Igor Russkikh <igor.russkikh@aquantia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_llh.h b/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_llh.h
index 7056c7342afc..41f239928c15 100644
--- a/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_llh.h
+++ b/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_llh.h
@@ -325,6 +325,9 @@ void hw_atl_rpb_rx_pkt_buff_size_per_tc_set(struct aq_hw_s *aq_hw,
 					    u32 rx_pkt_buff_size_per_tc,
 					    u32 buffer);
 
+/* set rdm rx dma descriptor cache init */
+void hw_atl_rdm_rx_dma_desc_cache_init_set(struct aq_hw_s *aq_hw, u32 init);
+
 /* set rx xoff enable (per tc) */
 void hw_atl_rpb_rx_xoff_en_per_tc_set(struct aq_hw_s *aq_hw, u32 rx_xoff_en_per_tc,
 				      u32 buffer);