Re: [PATCH v5 net-next 06/12] net: ethernet: ti: introduce cpsw switchdev based driver part 1 - dual-emac

From: Andrew Lunn
Date: Tue Oct 29 2019 - 08:32:45 EST


> +static int cpsw_probe(struct platform_device *pdev)
> +{
> + const struct soc_device_attribute *soc;
> + struct device *dev = &pdev->dev;
> + struct resource *ss_res;
> + struct cpsw_common *cpsw;
> + struct gpio_descs *mode;
> + void __iomem *ss_regs;
> + int ret = 0, ch;
> + struct clk *clk;
> + int irq;
> +

...

> +
> + /* setup netdevs */
> + ret = cpsw_create_ports(cpsw);
> + if (ret)
> + goto clean_unregister_netdev;

At this point, the slave ports go live. If the kernel is configured
with NFS root etc, it will start using the interfaces.

+
> + /* Grab RX and TX IRQs. Note that we also have RX_THRESHOLD and
> + * MISC IRQs which are always kept disabled with this driver so
> + * we will not request them.
> + *
> + * If anyone wants to implement support for those, make sure to
> + * first request and append them to irqs_table array.
> + */
> +
> + ret = devm_request_irq(dev, cpsw->irqs_table[0], cpsw_rx_interrupt,
> + 0, dev_name(dev), cpsw);
> + if (ret < 0) {
> + dev_err(dev, "error attaching irq (%d)\n", ret);
> + goto clean_unregister_netdev;
> + }
> +
> + ret = devm_request_irq(dev, cpsw->irqs_table[1], cpsw_tx_interrupt,
> + 0, dev_name(dev), cpsw);
> + if (ret < 0) {
> + dev_err(dev, "error attaching irq (%d)\n", ret);
> + goto clean_unregister_netdev;
> + }

Are there any race conditions if the network starts using the devices
before interrupts are requested? To be safe, maybe this should be done
before the slaves are created?

Andrew