[PATCH 5.3 087/135] net: stmmac: xgmac: Disable Flow Control when 1 or more queues are in AV

Greg Kroah-Hartman
2019-12-03T23:09:11Z

From: Jose Abreu <Jose.Abreu@synopsys.com>

[ Upstream commit 132f2f20c9866325d12c155aca06d260f358d3cb ]

When in AVB mode we need to disable flow control to prevent MAC from
pausing in TX side.

Fixes: ec6ea8e3eee9 ("net: stmmac: Add CBS support in XGMAC2")
Signed-off-by: Jose Abreu <Jose.Abreu@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
index a4f236e3593e7..28dc3b33606e1 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
@@ -441,6 +441,7 @@ static void dwxgmac2_enable_tso(void __iomem *ioaddr, bool en, u32 chan)
static void dwxgmac2_qmode(void __iomem *ioaddr, u32 channel, u8 qmode)
{
u32 value = readl(ioaddr + XGMAC_MTL_TXQ_OPMODE(channel));
+ u32 flow = readl(ioaddr + XGMAC_RX_FLOW_CTRL);

value &= ~XGMAC_TXQEN;
if (qmode != MTL_QUEUE_AVB) {
@@ -448,6 +449,7 @@ static void dwxgmac2_qmode(void __iomem *ioaddr, u32 channel, u8 qmode)
writel(0, ioaddr + XGMAC_MTL_TCx_ETS_CONTROL(channel));
} else {
value |= 0x1 << XGMAC_TXQEN_SHIFT;
+ writel(flow & (~XGMAC_RFE), ioaddr + XGMAC_RX_FLOW_CTRL);
}

writel(value, ioaddr + XGMAC_MTL_TXQ_OPMODE(channel));
--
2.20.1