[PATCH net v2 08/10] net: stmmac: xgmac: Disable Flow Control when 1 or more queues are in AV

From: Jose Abreu
Date: Thu Oct 31 2019 - 07:01:11 EST


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@xxxxxxxxxxxx>

---
Cc: Giuseppe Cavallaro <peppe.cavallaro@xxxxxx>
Cc: Alexandre Torgue <alexandre.torgue@xxxxxx>
Cc: Jose Abreu <joabreu@xxxxxxxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Maxime Coquelin <mcoquelin.stm32@xxxxxxxxx>
Cc: netdev@xxxxxxxxxxxxxxx
Cc: linux-stm32@xxxxxxxxxxxxxxxxxxxxxxxxxxxx
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
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 7bd1447f9f47..f148cb2061d8 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
@@ -473,6 +473,7 @@ 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) {
@@ -480,6 +481,7 @@ 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));
--
2.7.4