net: mediatek: add next data pointer coherency protection

The QDMA engine can fail to update the register pointing to the next TX
descriptor if this bit does not get set in the QDMA configuration register.
Not setting this bit can result in invalid values inside the TX rings
registers which will causes TX stalls.

Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index b6d3c21..f30c2e4 100644 (file)
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -1282,7 +1282,7 @@ static int mtk_start_dma(struct mtk_eth *eth)
        mtk_w32(eth,
                MTK_TX_WB_DDONE | MTK_RX_DMA_EN | MTK_TX_DMA_EN |
                MTK_RX_2B_OFFSET | MTK_DMA_SIZE_16DWORDS |
-               MTK_RX_BT_32DWORDS,
+               MTK_RX_BT_32DWORDS | MTK_NDP_CO_PRO,
                MTK_QDMA_GLO_CFG);
 
        return 0;

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.h b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
index 57f7e8a..a5eb7c6 100644 (file)
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
@@ -91,6 +91,7 @@
 #define MTK_QDMA_GLO_CFG       0x1A04
 #define MTK_RX_2B_OFFSET       BIT(31)
 #define MTK_RX_BT_32DWORDS     (3 << 11)
+#define MTK_NDP_CO_PRO         BIT(10)
 #define MTK_TX_WB_DDONE                BIT(6)
 #define MTK_DMA_SIZE_16DWORDS  (2 << 4)
 #define MTK_RX_DMA_BUSY                BIT(3)