[PATCH 4.20 072/183] net: stmmac: dwxgmac2: Only clear interrupts that are active

[Greg Kroah-Hartman]

4.20-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 6c5092e7771cd..c5e25580a43fa 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
@@ -263,6 +263,7 @@ 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 */
@@ -282,8 +283,7 @@ 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;
 			}
@@ -295,7 +295,7 @@ 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