[PATCH AUTOSEL 5.1 26/70] net: stmmac: update rx tail pointer register to fix rx dma hang issue.

From: Sasha Levin
Date: Sat Jun 08 2019 - 07:58:43 EST

From: Biao Huang <biao.huang@xxxxxxxxxxxx>

[ Upstream commit 4523a5611526709ec9b4e2574f1bb7818212651e ]

Currently we will not update the receive descriptor tail pointer in
stmmac_rx_refill. Rx dma will think no available descriptors and stop
once received packets exceed DMA_RX_SIZE, so that the rx only test will fail.

Update the receive tail pointer in stmmac_rx_refill to add more descriptors
to the rx channel, so packets can be received continually

Fixes: 54139cf3bb33 ("net: stmmac: adding multiple buffers for rx")
Signed-off-by: Biao Huang <biao.huang@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 3c409862c52e..8cebc44108b2 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -3338,6 +3338,7 @@ static inline void stmmac_rx_refill(struct stmmac_priv *priv, u32 queue)
rx_q->dirty_rx = entry;
+ stmmac_set_rx_tail_ptr(priv, priv->ioaddr, rx_q->rx_tail_addr, queue);