From cd2d6d33e2c5be653d10cdc8fcd7dcf0be28de50 Mon Sep 17 00:00:00 2001 From: Tony Lindgren Date: Thu, 15 Jan 2015 14:45:09 -0800 Subject: [PATCH] net: davinci_emac: Fix hangs with interrupts On davinci_emac, we have pulse interrupts. This means that we need to clear the EOI bits when disabling interrupts as otherwise the interrupts keep happening. And we also need to not clear the EOI bits again when enabling the interrupts as otherwise we will get tons of: unexpected IRQ trap at vector 00 These errors almost certainly mean that the omap-intc.c is signaling a spurious interrupt with the reserved irq 127 as we've seen earlier on omap3. Let's fix the issue by clearing the EOI bits when disabling the interrupts. Let's also keep the comment for "Rx Threshold and Misc interrupts are not enabled" for both enable and disable so people are aware of this when potentially adding more support. Note that eventually we should handle the RX and TX interrupts separately like cpsw is now doing. However, so far I have not seen any issues with this based on my testing, so it seems to behave a little different compared to the cpsw that had a similar issue. Cc: Brian Hutchinson Reviewed-by: Felipe Balbi Signed-off-by: Tony Lindgren Signed-off-by: David S. Miller --- drivers/net/ethernet/ti/davinci_emac.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/drivers/net/ethernet/ti/davinci_emac.c b/drivers/net/ethernet/ti/davinci_emac.c index ea712512c7d1..383ed527dad9 100644 --- a/drivers/net/ethernet/ti/davinci_emac.c +++ b/drivers/net/ethernet/ti/davinci_emac.c @@ -922,6 +922,16 @@ static void emac_int_disable(struct emac_priv *priv) if (priv->int_disable) priv->int_disable(); + /* NOTE: Rx Threshold and Misc interrupts are not enabled */ + + /* ack rxen only then a new pulse will be generated */ + emac_write(EMAC_DM646X_MACEOIVECTOR, + EMAC_DM646X_MAC_EOI_C0_RXEN); + + /* ack txen- only then a new pulse will be generated */ + emac_write(EMAC_DM646X_MACEOIVECTOR, + EMAC_DM646X_MAC_EOI_C0_TXEN); + local_irq_restore(flags); } else { @@ -951,15 +961,6 @@ static void emac_int_enable(struct emac_priv *priv) * register */ /* NOTE: Rx Threshold and Misc interrupts are not enabled */ - - /* ack rxen only then a new pulse will be generated */ - emac_write(EMAC_DM646X_MACEOIVECTOR, - EMAC_DM646X_MAC_EOI_C0_RXEN); - - /* ack txen- only then a new pulse will be generated */ - emac_write(EMAC_DM646X_MACEOIVECTOR, - EMAC_DM646X_MAC_EOI_C0_TXEN); - } else { /* Set DM644x control registers for interrupt control */ emac_ctrl_write(EMAC_CTRL_EWCTL, 0x1); -- 2.39.5