[PATCH net-next 1/3] net: stmmac: xgmac: Disable RX FIFO Overflow interrupts

[Andrew Lunn]

On Mon, Jul 14, 2025 at 03:59:17PM +0800, Rohan G Thomas via B4 Relay wrote:
> From: Rohan G Thomas <rohan.g.thomas at altera.com>
> 
> Enabling RX FIFO Overflow interrupts is counterproductive
> and causes an interrupt storm when RX FIFO overflows.
> Disabling this interrupt has no side effect and eliminates
> interrupt storms when the RX FIFO overflows.
> 
> Commit 8a7cb245cf28 ("net: stmmac: Do not enable RX FIFO
> overflow interrupts") disables RX FIFO overflow interrupts
> for DWMAC4 IP and removes the corresponding handling of
> this interrupt. This patch is doing the same thing for
> XGMAC IP.
> 
> Signed-off-by: Rohan G Thomas <rohan.g.thomas at altera.com>
> Reviewed-by: Matthew Gerlach <matthew.gerlach at altera.com>

Please take a read of:

https://www.kernel.org/doc/html/latest/process/maintainer-netdev.html

This appears to be a fixed, so the Subject: line should indicate this.
Please also include a Fixes: tag, and Cc: stable.

> ---
>  drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c | 4 ----
>  1 file changed, 4 deletions(-)
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
> index 5dcc95bc0ad28b756accf9670c5fa00aa94fcfe3..7201a38842651a865493fce0cefe757d6ae9bafa 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
> @@ -203,10 +203,6 @@ static void dwxgmac2_dma_rx_mode(struct stmmac_priv *priv, void __iomem *ioaddr,
>  	}
>  
>  	writel(value, ioaddr + XGMAC_MTL_RXQ_OPMODE(channel));
> -
> -	/* Enable MTL RX overflow */
> -	value = readl(ioaddr + XGMAC_MTL_QINTEN(channel));
> -	writel(value | XGMAC_RXOIE, ioaddr + XGMAC_MTL_QINTEN(channel));

What is the reset default? Would it make sense to explicitly disable
it, rather than never enable it? What does 8a7cb245cf28 do?

    Andrew

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