[PATCH 3/7] net: smc911x: Properly handle EEPROM MAC address

[Ramon Fried]

On Thu, Jun 11, 2020 at 2:05 PM Andre Przywara <andre.przywara at arm.com> wrote:
>
> When compiled as a DM_ETH driver, the scm911x driver was reading the MAC
> address from the optional EEPROM storage, but failed to copy this to the
> platdata struct. Since it was also missing a definition of the
> read_rom_hwaddr() function, the generic Ethernet code was dismissing
> this MAC address, falling back to a random address or denying to start
> at all.
>
> Add an implementation of .read_rom_hwaddr, and refactor the function
> reading the ROM address to be called by all interested parties.
>
> This fixes MAC address issues when using the driver in DM_ETH "mode".
>
> Signed-off-by: Andre Przywara <andre.przywara at arm.com>
> ---
>  drivers/net/smc911x.c | 60 ++++++++++++++++++++++++++-----------------
>  1 file changed, 36 insertions(+), 24 deletions(-)
>
> diff --git a/drivers/net/smc911x.c b/drivers/net/smc911x.c
> index 9d2790e561..053ff9f4ff 100644
> --- a/drivers/net/smc911x.c
> +++ b/drivers/net/smc911x.c
> @@ -187,6 +187,26 @@ static void smc911x_handle_mac_address(struct smc911x_priv *priv)
>         printf(DRIVERNAME ": MAC %pM\n", m);
>  }
>
> +static bool smc911x_read_mac_address(struct smc911x_priv *priv)
> +{
> +       u32 addrh, addrl;
> +
> +       /* address is obtained from optional eeprom */
> +       addrh = smc911x_get_mac_csr(priv, ADDRH);
> +       addrl = smc911x_get_mac_csr(priv, ADDRL);
> +       if (addrl == 0xffffffff && addrh == 0x0000ffff)
> +               return false;
> +
> +       priv->enetaddr[0] = addrl;
> +       priv->enetaddr[1] = addrl >>  8;
> +       priv->enetaddr[2] = addrl >> 16;
> +       priv->enetaddr[3] = addrl >> 24;
> +       priv->enetaddr[4] = addrh;
> +       priv->enetaddr[5] = addrh >> 8;
> +
> +       return true;
> +}
> +
>  static int smc911x_eth_phy_read(struct smc911x_priv *priv,
>                                 u8 phy, u8 reg, u16 *val)
>  {
> @@ -471,7 +491,6 @@ static int smc911x_recv(struct eth_device *dev)
>
>  int smc911x_initialize(u8 dev_num, int base_addr)
>  {
> -       unsigned long addrl, addrh;
>         struct smc911x_priv *priv;
>         int ret;
>
> @@ -489,18 +508,8 @@ int smc911x_initialize(u8 dev_num, int base_addr)
>                 goto err_detect;
>         }
>
> -       addrh = smc911x_get_mac_csr(priv, ADDRH);
> -       addrl = smc911x_get_mac_csr(priv, ADDRL);
> -       if (!(addrl == 0xffffffff && addrh == 0x0000ffff)) {
> -               /* address is obtained from optional eeprom */
> -               priv->enetaddr[0] = addrl;
> -               priv->enetaddr[1] = addrl >>  8;
> -               priv->enetaddr[2] = addrl >> 16;
> -               priv->enetaddr[3] = addrl >> 24;
> -               priv->enetaddr[4] = addrh;
> -               priv->enetaddr[5] = addrh >> 8;
> +       if (smc911x_read_mac_address(priv))
>                 memcpy(priv->dev.enetaddr, priv->enetaddr, 6);
> -       }
>
>         priv->dev.init = smc911x_init;
>         priv->dev.halt = smc911x_halt;
> @@ -565,6 +574,19 @@ static int smc911x_recv(struct udevice *dev, int flags, uchar **packetp)
>         return ret ? ret : -EAGAIN;
>  }
>
> +static int smc911x_read_rom_hwaddr(struct udevice *dev)
> +{
> +       struct smc911x_priv *priv = dev_get_priv(dev);
> +       struct eth_pdata *pdata = dev_get_platdata(dev);
> +
> +       if (!smc911x_read_mac_address(priv))
> +               return -ENODEV;
> +
> +       memcpy(pdata->enetaddr, priv->enetaddr, sizeof(pdata->enetaddr));
> +
> +       return 0;
> +}
> +
>  static int smc911x_bind(struct udevice *dev)
>  {
>         return device_set_name(dev, dev->name);
> @@ -573,7 +595,6 @@ static int smc911x_bind(struct udevice *dev)
>  static int smc911x_probe(struct udevice *dev)
>  {
>         struct smc911x_priv *priv = dev_get_priv(dev);
> -       unsigned long addrh, addrl;
>         int ret;
>
>         /* Try to detect chip. Will fail if not present. */
> @@ -581,17 +602,7 @@ static int smc911x_probe(struct udevice *dev)
>         if (ret)
>                 return ret;
>
> -       addrh = smc911x_get_mac_csr(priv, ADDRH);
> -       addrl = smc911x_get_mac_csr(priv, ADDRL);
> -       if (!(addrl == 0xffffffff && addrh == 0x0000ffff)) {
> -               /* address is obtained from optional eeprom */
> -               priv->enetaddr[0] = addrl;
> -               priv->enetaddr[1] = addrl >>  8;
> -               priv->enetaddr[2] = addrl >> 16;
> -               priv->enetaddr[3] = addrl >> 24;
> -               priv->enetaddr[4] = addrh;
> -               priv->enetaddr[5] = addrh >> 8;
> -       }
> +       smc911x_read_rom_hwaddr(dev);
>
>         return 0;
>  }
> @@ -612,6 +623,7 @@ static const struct eth_ops smc911x_ops = {
>         .send   = smc911x_send,
>         .recv   = smc911x_recv,
>         .stop   = smc911x_stop,
> +       .read_rom_hwaddr = smc911x_read_rom_hwaddr,
>  };
>
>  static const struct udevice_id smc911x_ids[] = {
> --
> 2.17.5
>
Reviewed-By: Ramon Fried <rfried.dev at gmail.com>