Re: [PATCH net-next v3 3/3] net: stmmac: Add driver support for DWMAC5 fault IRQ Support

[Andrew Halaney]

On Thu, Nov 23, 2023 at 05:08:15PM +0530, Suraj Jaiswal wrote:
> Add IRQ support to listen HW fault like ECC,DPP,FSM
> fault and print the fault information in the kernel
> log.
> 
> Signed-off-by: Suraj Jaiswal <quic_jsuraj@xxxxxxxxxxx>
> ---
>  drivers/net/ethernet/stmicro/stmmac/common.h  |  1 +
>  drivers/net/ethernet/stmicro/stmmac/stmmac.h  |  2 ++
>  .../net/ethernet/stmicro/stmmac/stmmac_main.c | 18 +++++++++++++++++
>  .../ethernet/stmicro/stmmac/stmmac_platform.c | 20 +++++++++++++++++++
>  4 files changed, 41 insertions(+)
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/common.h b/drivers/net/ethernet/stmicro/stmmac/common.h
> index 6b935922054d..c4821c7ab674 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/common.h
> +++ b/drivers/net/ethernet/stmicro/stmmac/common.h
> @@ -347,6 +347,7 @@ enum request_irq_err {
>  	REQ_IRQ_ERR_SFTY_UE,
>  	REQ_IRQ_ERR_SFTY_CE,
>  	REQ_IRQ_ERR_LPI,
> +	REQ_IRQ_ERR_SAFETY,
>  	REQ_IRQ_ERR_WOL,
>  	REQ_IRQ_ERR_MAC,
>  	REQ_IRQ_ERR_NO,
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
> index cd7a9768de5f..8893d4b7fa38 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
> @@ -33,6 +33,7 @@ struct stmmac_resources {
>  	int irq;
>  	int sfty_ce_irq;
>  	int sfty_ue_irq;
> +	int safety_common_intr;
>  	int rx_irq[MTL_MAX_RX_QUEUES];
>  	int tx_irq[MTL_MAX_TX_QUEUES];
>  };
> @@ -331,6 +332,7 @@ struct stmmac_priv {
>  	/* XDP BPF Program */
>  	unsigned long *af_xdp_zc_qps;
>  	struct bpf_prog *xdp_prog;
> +	int safety_common_intr;
>  };
>  
>  enum stmmac_state {
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> index 8964fc8a955f..2ae4f34444de 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> @@ -3530,6 +3530,10 @@ static void stmmac_free_irq(struct net_device *dev,
>  		if (priv->wol_irq > 0 && priv->wol_irq != dev->irq)
>  			free_irq(priv->wol_irq, dev);
>  		fallthrough;
> +	case REQ_IRQ_ERR_SAFETY:
> +		if (priv->safety_common_intr > 0 && priv->safety_common_intr != dev->irq)
> +			free_irq(priv->safety_common_intr, dev);
> +		fallthrough;
>  	case REQ_IRQ_ERR_WOL:
>  		free_irq(dev->irq, dev);
>  		fallthrough;
> @@ -3736,6 +3740,18 @@ static int stmmac_request_irq_single(struct net_device *dev)
>  		}
>  	}
>  
> +	if (priv->safety_common_intr > 0 && priv->safety_common_intr != dev->irq) {
> +		ret = request_irq(priv->safety_common_intr, stmmac_safety_interrupt,
> +				  0, "safety", dev);
> +		if (unlikely(ret < 0)) {
> +			netdev_err(priv->dev,
> +				   "%s: alloc safety failed %d (error: %d)\n",
> +				   __func__, priv->safety_common_intr, ret);
> +			irq_err = REQ_IRQ_ERR_SAFETY;
> +			goto irq_error;
> +		}
> +	}
> +
>  	return 0;
>  
>  irq_error:
> @@ -7398,6 +7414,8 @@ int stmmac_dvr_probe(struct device *device,
>  	priv->lpi_irq = res->lpi_irq;
>  	priv->sfty_ce_irq = res->sfty_ce_irq;
>  	priv->sfty_ue_irq = res->sfty_ue_irq;
> +	priv->safety_common_intr = res->safety_common_intr;
> +
>  	for (i = 0; i < MTL_MAX_RX_QUEUES; i++)
>  		priv->rx_irq[i] = res->rx_irq[i];
>  	for (i = 0; i < MTL_MAX_TX_QUEUES; i++)
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
> index 1ffde555da47..bae1704d5f4b 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
> @@ -690,9 +690,25 @@ devm_stmmac_probe_config_dt(struct platform_device *pdev, u8 *mac)
>  #endif /* CONFIG_OF */
>  EXPORT_SYMBOL_GPL(devm_stmmac_probe_config_dt);
>  
> +int stmmac_get_fault_intr_config(struct platform_device *pdev, struct stmmac_resources *res)
> +{
> +	int ret = 0;
> +
> +	res->safety_common_intr = platform_get_irq_byname(pdev, "safety");
> +
> +	if (res->safety_common_intr < 0) {
> +		if (res->safety_common_intr != -EPROBE_DEFER)
> +			dev_err(&pdev->dev, "safety IRQ configuration information not found\n");
> +		ret = 1;
> +	}
> +
> +	return ret;
> +}

I think other reviewers have covered most of what I want to say, but
I think this doesn't deserve its own function and should just be done
directly, as is done for eth_lpi for example. I think it also should be
considered an optional interrupt based on my understanding of its
purpose (just like eth_lpi).

> +
>  int stmmac_get_platform_resources(struct platform_device *pdev,
>  				  struct stmmac_resources *stmmac_res)
>  {
> +	int ret = 0;
>  	memset(stmmac_res, 0, sizeof(*stmmac_res));
>  
>  	/* Get IRQ information early to have an ability to ask for deferred
> @@ -702,6 +718,10 @@ int stmmac_get_platform_resources(struct platform_device *pdev,
>  	if (stmmac_res->irq < 0)
>  		return stmmac_res->irq;
>  
> +	ret = stmmac_get_fault_intr_config(pdev, stmmac_res);
> +	if (ret)
> +		dev_err(&pdev->dev, "Fault interrupt not present\n");
> +
>  	/* On some platforms e.g. SPEAr the wake up irq differs from the mac irq
>  	 * The external wake up irq can be passed through the platform code
>  	 * named as "eth_wake_irq"
> -- 
> 2.25.1
>