From a8184003c0bb1d6362c2af76c560b3caae6832cb Mon Sep 17 00:00:00 2001 From: Rabin Vincent Date: Tue, 23 Aug 2016 16:31:28 +0200 Subject: [PATCH] dwc_eth_qos: fix interrupt enable race We currently enable interrupts before we enable NAPI. If an RX interrupt hits before we enabled NAPI then the NAPI callback is never called and we leave the hardware with RX interrupts disabled, which of course leads us to never handling received packets. Fix this by moving the interrupt enable to after we've enable NAPI and the reclaim tasklet. Fixes: cd5e41234729 ("dwc_eth_qos: do phy_start before resetting hardware") Signed-off-by: Rabin Vincent Signed-off-by: Lars Persson Signed-off-by: David S. Miller --- drivers/net/ethernet/synopsys/dwc_eth_qos.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/synopsys/dwc_eth_qos.c b/drivers/net/ethernet/synopsys/dwc_eth_qos.c index 9f159a775af3..5a3941bf250f 100644 --- a/drivers/net/ethernet/synopsys/dwc_eth_qos.c +++ b/drivers/net/ethernet/synopsys/dwc_eth_qos.c @@ -1622,13 +1622,7 @@ static void dwceqos_init_hw(struct net_local *lp) DWCEQOS_MMC_CTRL_RSTONRD); dwceqos_enable_mmc_interrupt(lp); - /* Enable Interrupts */ - dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_IE, - DWCEQOS_DMA_CH0_IE_NIE | - DWCEQOS_DMA_CH0_IE_RIE | DWCEQOS_DMA_CH0_IE_TIE | - DWCEQOS_DMA_CH0_IE_AIE | - DWCEQOS_DMA_CH0_IE_FBEE); - + dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_IE, 0); dwceqos_write(lp, REG_DWCEQOS_MAC_IE, 0); dwceqos_write(lp, REG_DWCEQOS_MAC_CFG, DWCEQOS_MAC_CFG_IPC | @@ -1905,6 +1899,15 @@ static int dwceqos_open(struct net_device *ndev) netif_start_queue(ndev); tasklet_enable(&lp->tx_bdreclaim_tasklet); + /* Enable Interrupts -- do this only after we enable NAPI and the + * tasklet. + */ + dwceqos_write(lp, REG_DWCEQOS_DMA_CH0_IE, + DWCEQOS_DMA_CH0_IE_NIE | + DWCEQOS_DMA_CH0_IE_RIE | DWCEQOS_DMA_CH0_IE_TIE | + DWCEQOS_DMA_CH0_IE_AIE | + DWCEQOS_DMA_CH0_IE_FBEE); + return 0; } -- 2.30.2