Re: [PATCH 1/1] net: ftgmac100: add handling of mdio/phy nodes for ast2400/2500

From: Joel Stanley
Date: Wed Oct 14 2020 - 04:59:38 EST


Hi Ivan,

On Tue, 13 Oct 2020 at 12:38, Ivan Mikhaylov <i.mikhaylov@xxxxxxxxx> wrote:
>
> phy-handle can't be handled well for ast2400/2500 which has an embedded
> MDIO controller. Add ftgmac100_mdio_setup for ast2400/2500 and initialize
> PHYs from mdio child node with of_mdiobus_register.

Good idea. The driver has become a mess of different ways to connect
the phy and it needs to be cleaned up. I have a patch that fixes
rmmod, which is currently broken.



>
> Signed-off-by: Ivan Mikhaylov <i.mikhaylov@xxxxxxxxx>
> ---
> drivers/net/ethernet/faraday/ftgmac100.c | 114 ++++++++++++++---------
> 1 file changed, 69 insertions(+), 45 deletions(-)
>
> diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c
> index 87236206366f..e32066519ec1 100644
> --- a/drivers/net/ethernet/faraday/ftgmac100.c
> +++ b/drivers/net/ethernet/faraday/ftgmac100.c
> @@ -1044,11 +1044,47 @@ static void ftgmac100_adjust_link(struct net_device *netdev)
> schedule_work(&priv->reset_task);
> }
>
> -static int ftgmac100_mii_probe(struct ftgmac100 *priv, phy_interface_t intf)
> +static int ftgmac100_mii_probe(struct net_device *netdev)
> {
> - struct net_device *netdev = priv->netdev;
> + struct ftgmac100 *priv = netdev_priv(netdev);
> + struct platform_device *pdev = to_platform_device(priv->dev);
> + struct device_node *np = pdev->dev.of_node;
> + phy_interface_t phy_intf = PHY_INTERFACE_MODE_RGMII;
> struct phy_device *phydev;
>
> + /* Get PHY mode from device-tree */
> + if (np) {
> + /* Default to RGMII. It's a gigabit part after all */
> + phy_intf = of_get_phy_mode(np, &phy_intf);
> + if (phy_intf < 0)
> + phy_intf = PHY_INTERFACE_MODE_RGMII;
> +
> + /* Aspeed only supports these. I don't know about other IP
> + * block vendors so I'm going to just let them through for
> + * now. Note that this is only a warning if for some obscure
> + * reason the DT really means to lie about it or it's a newer
> + * part we don't know about.
> + *
> + * On the Aspeed SoC there are additionally straps and SCU
> + * control bits that could tell us what the interface is
> + * (or allow us to configure it while the IP block is held
> + * in reset). For now I chose to keep this driver away from
> + * those SoC specific bits and assume the device-tree is
> + * right and the SCU has been configured properly by pinmux
> + * or the firmware.
> + */
> + if (priv->is_aspeed &&
> + phy_intf != PHY_INTERFACE_MODE_RMII &&
> + phy_intf != PHY_INTERFACE_MODE_RGMII &&
> + phy_intf != PHY_INTERFACE_MODE_RGMII_ID &&
> + phy_intf != PHY_INTERFACE_MODE_RGMII_RXID &&
> + phy_intf != PHY_INTERFACE_MODE_RGMII_TXID) {
> + netdev_warn(netdev,
> + "Unsupported PHY mode %s !\n",
> + phy_modes(phy_intf));
> + }

Why do we move this?

> + }
> +
> phydev = phy_find_first(priv->mii_bus);
> if (!phydev) {
> netdev_info(netdev, "%s: no PHY found\n", netdev->name);
> @@ -1056,7 +1092,7 @@ static int ftgmac100_mii_probe(struct ftgmac100 *priv, phy_interface_t intf)
> }
>
> phydev = phy_connect(netdev, phydev_name(phydev),
> - &ftgmac100_adjust_link, intf);
> + &ftgmac100_adjust_link, phy_intf);
>
> if (IS_ERR(phydev)) {
> netdev_err(netdev, "%s: Could not attach to PHY\n", netdev->name);
> @@ -1601,8 +1637,8 @@ static int ftgmac100_setup_mdio(struct net_device *netdev)
> {
> struct ftgmac100 *priv = netdev_priv(netdev);
> struct platform_device *pdev = to_platform_device(priv->dev);
> - phy_interface_t phy_intf = PHY_INTERFACE_MODE_RGMII;
> struct device_node *np = pdev->dev.of_node;
> + struct device_node *mdio_np;
> int i, err = 0;
> u32 reg;
>
> @@ -1623,39 +1659,6 @@ static int ftgmac100_setup_mdio(struct net_device *netdev)
> iowrite32(reg, priv->base + FTGMAC100_OFFSET_REVR);
> }
>
> - /* Get PHY mode from device-tree */
> - if (np) {
> - /* Default to RGMII. It's a gigabit part after all */
> - err = of_get_phy_mode(np, &phy_intf);
> - if (err)
> - phy_intf = PHY_INTERFACE_MODE_RGMII;
> -
> - /* Aspeed only supports these. I don't know about other IP
> - * block vendors so I'm going to just let them through for
> - * now. Note that this is only a warning if for some obscure
> - * reason the DT really means to lie about it or it's a newer
> - * part we don't know about.
> - *
> - * On the Aspeed SoC there are additionally straps and SCU
> - * control bits that could tell us what the interface is
> - * (or allow us to configure it while the IP block is held
> - * in reset). For now I chose to keep this driver away from
> - * those SoC specific bits and assume the device-tree is
> - * right and the SCU has been configured properly by pinmux
> - * or the firmware.
> - */
> - if (priv->is_aspeed &&
> - phy_intf != PHY_INTERFACE_MODE_RMII &&
> - phy_intf != PHY_INTERFACE_MODE_RGMII &&
> - phy_intf != PHY_INTERFACE_MODE_RGMII_ID &&
> - phy_intf != PHY_INTERFACE_MODE_RGMII_RXID &&
> - phy_intf != PHY_INTERFACE_MODE_RGMII_TXID) {
> - netdev_warn(netdev,
> - "Unsupported PHY mode %s !\n",
> - phy_modes(phy_intf));
> - }
> - }
> -
> priv->mii_bus->name = "ftgmac100_mdio";
> snprintf(priv->mii_bus->id, MII_BUS_ID_SIZE, "%s-%d",
> pdev->name, pdev->id);
> @@ -1667,22 +1670,22 @@ static int ftgmac100_setup_mdio(struct net_device *netdev)
> for (i = 0; i < PHY_MAX_ADDR; i++)
> priv->mii_bus->irq[i] = PHY_POLL;
>
> - err = mdiobus_register(priv->mii_bus);
> + mdio_np = of_get_child_by_name(np, "mdio");
> + if (mdio_np)
> + err = of_mdiobus_register(priv->mii_bus, mdio_np);
> + else
> + err = mdiobus_register(priv->mii_bus);
> +
> if (err) {
> dev_err(priv->dev, "Cannot register MDIO bus!\n");
> goto err_register_mdiobus;
> }
>
> - err = ftgmac100_mii_probe(priv, phy_intf);
> - if (err) {
> - dev_err(priv->dev, "MII Probe failed!\n");
> - goto err_mii_probe;
> - }
> + if (mdio_np)
> + of_node_put(mdio_np);

By the time I get down here I'm lost. Do you think you could split the
change up into a few smaller patches?

If not, try to explain what the various hunks of your change are trying to do.

Cheers,

Joel

>
> return 0;
>
> -err_mii_probe:
> - mdiobus_unregister(priv->mii_bus);
> err_register_mdiobus:
> mdiobus_free(priv->mii_bus);
> return err;
> @@ -1836,10 +1839,23 @@ static int ftgmac100_probe(struct platform_device *pdev)
> } else if (np && of_get_property(np, "phy-handle", NULL)) {
> struct phy_device *phy;
>
> + /* Support "mdio"/"phy" child nodes for ast2400/2500 with
> + * an embedded MDIO controller. Automatically scan the DTS for
> + * available PHYs and register them.
> + */
> + if (of_device_is_compatible(np, "aspeed,ast2400-mac") ||
> + of_device_is_compatible(np, "aspeed,ast2500-mac")) {
> + err = ftgmac100_setup_mdio(netdev);
> + if (err)
> + goto err_setup_mdio;
> + }
> +
> phy = of_phy_get_and_connect(priv->netdev, np,
> &ftgmac100_adjust_link);
> if (!phy) {
> dev_err(&pdev->dev, "Failed to connect to phy\n");
> + if (priv->mii_bus)
> + mdiobus_unregister(priv->mii_bus);
> goto err_setup_mdio;
> }
>
> @@ -1860,6 +1876,14 @@ static int ftgmac100_probe(struct platform_device *pdev)
> err = ftgmac100_setup_mdio(netdev);
> if (err)
> goto err_setup_mdio;
> +
> + err = ftgmac100_mii_probe(netdev);
> + if (err) {
> + dev_err(priv->dev, "MII probe failed!\n");
> + mdiobus_unregister(priv->mii_bus);
> + goto err_setup_mdio;
> + }
> +
> }
>
> if (priv->is_aspeed) {
> --
> 2.21.1
>