[PATCH 4.19 061/152] net: stmmac: dwxgmac2: Only clear interrupts that are active

From: Greg Kroah-Hartman
Date: Mon Feb 25 2019 - 16:23:48 EST


4.19-stable review patch. If anyone has any objections, please let me know.

------------------

[ Upstream commit fcc509eb10ff4794641e6ad3082118287a750d0a ]

In DMA interrupt handler we were clearing all interrupts status, even
the ones that were not active. Fix this and only clear the active
interrupts.

Cc: Joao Pinto <jpinto@xxxxxxxxxxxx>
Cc: David S. Miller <davem@xxxxxxxxxxxxx>
Cc: Giuseppe Cavallaro <peppe.cavallaro@xxxxxx>
Cc: Alexandre Torgue <alexandre.torgue@xxxxxx>
Signed-off-by: Jose Abreu <joabreu@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
index 20909036e0028..1c39305274440 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
@@ -260,6 +260,7 @@ static int dwxgmac2_dma_interrupt(void __iomem *ioaddr,
struct stmmac_extra_stats *x, u32 chan)
{
u32 intr_status = readl(ioaddr + XGMAC_DMA_CH_STATUS(chan));
+ u32 intr_en = readl(ioaddr + XGMAC_DMA_CH_INT_EN(chan));
int ret = 0;

/* ABNORMAL interrupts */
@@ -279,8 +280,7 @@ static int dwxgmac2_dma_interrupt(void __iomem *ioaddr,
x->normal_irq_n++;

if (likely(intr_status & XGMAC_RI)) {
- u32 value = readl(ioaddr + XGMAC_DMA_CH_INT_EN(chan));
- if (likely(value & XGMAC_RIE)) {
+ if (likely(intr_en & XGMAC_RIE)) {
x->rx_normal_irq_n++;
ret |= handle_rx;
}
@@ -292,7 +292,7 @@ static int dwxgmac2_dma_interrupt(void __iomem *ioaddr,
}

/* Clear interrupts */
- writel(~0x0, ioaddr + XGMAC_DMA_CH_STATUS(chan));
+ writel(intr_en & intr_status, ioaddr + XGMAC_DMA_CH_STATUS(chan));

return ret;
}
--
2.19.1