[PATCH 5.13 190/300] net: stmmac: fix INTR TBU status affecting irq count statistic

From: Greg Kroah-Hartman
Date: Mon Sep 13 2021 - 10:09:37 EST


From: Voon Weifeng <weifeng.voon@xxxxxxxxx>

[ Upstream commit 1975df880b959e30f28d66148a12d77b458abd76 ]

DMA channel status "Transmit buffer unavailable(TBU)" bit is not
considered as a successful dma tx. Hence, it should not affect
all the irq count statistic.

Fixes: 1103d3a5531c ("net: stmmac: dwmac4: Also use TBU interrupt to clean TX path")
Signed-off-by: Voon Weifeng <weifeng.voon@xxxxxxxxx>
Signed-off-by: Vijayakannan Ayyathurai <vijayakannan.ayyathurai@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/stmicro/stmmac/dwmac4_lib.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_lib.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_lib.c
index e63270267578..f83db62938dd 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_lib.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_lib.c
@@ -172,11 +172,12 @@ int dwmac4_dma_interrupt(void __iomem *ioaddr,
x->rx_normal_irq_n++;
ret |= handle_rx;
}
- if (likely(intr_status & (DMA_CHAN_STATUS_TI |
- DMA_CHAN_STATUS_TBU))) {
+ if (likely(intr_status & DMA_CHAN_STATUS_TI)) {
x->tx_normal_irq_n++;
ret |= handle_tx;
}
+ if (unlikely(intr_status & DMA_CHAN_STATUS_TBU))
+ ret |= handle_tx;
if (unlikely(intr_status & DMA_CHAN_STATUS_ERI))
x->rx_early_irq++;

--
2.30.2