Re: [PATCH v1] ARM: i.MX8MP: skov: add MAC address assignment support

[Oleksij Rempel <linux@rempel-privat.de>]

Please ignore this patch. Ahmad gave me a better idea.

Am 12.03.24 um 11:00 schrieb Oleksij Rempel:
> Assign MAC address to main CPU interface and switch ports.
>
> Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
> ---
>   arch/arm/boards/skov-imx8mp/board.c | 131 ++++++++++++++++++++++++++++
>   arch/arm/dts/imx8mp-skov.dts        |   1 +
>   2 files changed, 132 insertions(+)
>
> diff --git a/arch/arm/boards/skov-imx8mp/board.c b/arch/arm/boards/skov-imx8mp/board.c
> index 3b6eb7b080..94d0bc75f9 100644
> --- a/arch/arm/boards/skov-imx8mp/board.c
> +++ b/arch/arm/boards/skov-imx8mp/board.c
> @@ -10,9 +10,12 @@
>   #include <gpio.h>
>   #include <init.h>
>   #include <io.h>
> +#include <linux/nvmem-consumer.h>
>   #include <mach/imx/bbu.h>
>   #include <mach/imx/generic.h>
>   #include <mach/imx/iomux-mx8mp.h>
> +#include <net.h>
> +#include <of_net.h>
>
>   struct skov_imx8mp_priv {
>   	struct device *dev;
> @@ -85,6 +88,134 @@ static const struct board_description imx8mp_variants[] = {
>   	},
>   };
>
> +static void skov_imx8mp_get_src_mac(struct skov_imx8mp_priv *priv,
> +				   struct device_node *s_np, u8 *mac,
> +				   int dst_id)
> +{
> +	char str[sizeof("xx:xx:xx:xx:xx:xx")];
> +	struct eth_device *s_edev;
> +	int ret;
> +
> +	s_edev = of_find_eth_device_by_node(s_np);
> +	if (s_edev && is_valid_ether_addr(s_edev->ethaddr)) {
> +		/* If the source device has a valid MAC address, use it in
> +		 * case address is overwritten by user.
> +		 */
> +		memcpy(mac, s_edev->ethaddr, ETH_ALEN);
> +		return;
> +	}
> +
> +	/* if the source device has no valid MAC address, try to get it from
> +	 * nvmem if it configured in the devicetree.
> +	 */
> +	ret = of_get_mac_addr_nvmem(s_np, mac);
> +	if (!ret)
> +		return;
> +
> +	/* if the source device has no valid MAC address, generate one with
> +	 * vendor OUI.
> +	 */
> +	ret = generate_ether_addr(mac, dst_id);
> +	if (ret)
> +		random_ether_addr(mac);
> +
> +	/* set SKOV OUI */
> +	mac[0] = 0x00;
> +	mac[1] = 0x0e;
> +	mac[2] = 0xcd;
> +	ethaddr_to_string(mac, str);
> +	dev_warn(priv->dev, "Failed to get eth addr for idx=%d. Generating one: %s\n",
> +		 dst_id, str);
> +}
> +
> +static int skov_imx8mp_eth_register_ethaddr(struct skov_imx8mp_priv *priv,
> +					    struct device_node *d_np,
> +					    struct device_node *s_np,
> +					    int dst_id)
> +{
> +	struct eth_device *d_edev;
> +	u8 mac[ETH_ALEN] = { 0 };
> +
> +	d_edev = of_find_eth_device_by_node(d_np);
> +	if (d_edev) {
> +		/* If the destination device already has a valid MAC address, do
> +		 * nothing, it was probably set to nv by user.
> +		 */
> +		if (is_valid_ether_addr(d_edev->ethaddr))
> +			return 0;
> +	}
> +
> +	skov_imx8mp_get_src_mac(priv, s_np, mac, dst_id);
> +
> +	of_eth_register_ethaddr(d_np, mac);
> +
> +	return 0;
> +}
> +
> +/* We have following requirements for the ethernet MAC addresses:
> + * - LAN1 MAC address should be the same as the MAC address stored in the FEC
> + *   slot (FEC is not used on this board).
> + * - LAN2 MAC address should be the same as the EQOS MAC address. (EQOS is
> + *   the master interface for the switch on this board, LAN2 and LAN1 are
> + *   external ports of this switch).
> + * - LAN2 MAC address is usually higher than LAN1 MAC address. But production
> + *   process do not guarantee this. So, we can't calculate LAN2 MAC address
> + *   from LAN1 MAC address.
> + */
> +static void skov_imx8mp_ethernet_init(struct skov_imx8mp_priv *priv)
> +{
> +	struct device_node *root;
> +	unsigned int i;
> +	struct eth_node_info {
> +		const char *s_alias;
> +		const char *d_alias;
> +	} eth_node_info[] = {
> +		{ "ethernet0", "ethernet0" }, /* EQOS -> EQOS */
> +		{ "ethernet0", "ethernet2" }, /* EQOS -> LAN2 */
> +		{ "ethernet3", "ethernet1" }, /* FEC -> LAN1 */
> +	};
> +
> +	root = of_get_root_node();
> +
> +	for (i = 0; i < ARRAY_SIZE(eth_node_info); i++) {
> +		const char *s_alias = eth_node_info[i].s_alias;
> +		const char *d_alias = eth_node_info[i].d_alias;
> +		struct device_node *s_np, *d_np;
> +		int ret;
> +
> +		s_np = of_find_node_by_alias(root, s_alias);
> +		if (!s_np) {
> +			dev_warn(priv->dev, "Failed to find src ethernet node by alias: %s\n",
> +				 s_alias);
> +			continue;
> +		}
> +
> +		d_np = of_find_node_by_alias(root, d_alias);
> +		if (!d_np) {
> +			dev_warn(priv->dev, "Failed to find dst ethernet node by alias: %s\n",
> +				 d_alias);
> +			continue;
> +		}
> +
> +		ret = skov_imx8mp_eth_register_ethaddr(priv, d_np, s_np, i);
> +		if (ret) {
> +			dev_warn(priv->dev, "Failed to transfer MAC address from alias %s to %s\n",
> +				 s_alias, d_alias);
> +			continue;
> +		}
> +	}
> +}
> +
> +static int skov_imx8mp_populate_ethaddr(void)
> +{
> +	struct skov_imx8mp_priv *priv = skov_imx8mp_priv;
> +
> +	skov_imx8mp_ethernet_init(priv);
> +
> +	return 0;
> +}
> +postenvironment_initcall(skov_imx8mp_populate_ethaddr);
> +
>   static int skov_imx8mp_fixup(struct device_node *root, void *data)
>   {
>   	struct device_node *chosen = of_create_node(root, "/chosen");
> diff --git a/arch/arm/dts/imx8mp-skov.dts b/arch/arm/dts/imx8mp-skov.dts
> index 3243a41697..063861427c 100644
> --- a/arch/arm/dts/imx8mp-skov.dts
> +++ b/arch/arm/dts/imx8mp-skov.dts
> @@ -31,6 +31,7 @@ aliases {
>   		ethernet0 = &eqos;
>   		ethernet1 = &lan1;
>   		ethernet2 = &lan2;
> +		ethernet3 = &fec;
>   		state = &state;
>   	};
>

--
Regards,
Oleksij