On Tue, Oct 12, 2021 at 02:35:53PM +0200, Alvin Šipraga wrote:
> +static struct sk_buff *rtl8_4_tag_rcv(struct sk_buff *skb,
> + struct net_device *dev)
> +{
> + __be16 *tag;
> + u16 etype;
> + u8 proto;
> + u8 port;
> +
> + if (unlikely(!pskb_may_pull(skb, RTL8_4_TAG_LEN)))
> + return NULL;
> +
> + tag = dsa_etype_header_pos_rx(skb);
> +
> + /* Parse Realtek EtherType */
> + etype = ntohs(tag[0]);
> + if (unlikely(etype != ETH_P_REALTEK)) {
> + dev_warn_ratelimited(&dev->dev,
> + "non-realtek ethertype 0x%04x\n", etype);
> + return NULL;
> + }
> +
> + /* Parse Protocol */
> + proto = ntohs(tag[1]) >> 8;
> + if (unlikely(proto != RTL8_4_PROTOCOL_RTL8365MB)) {
> + dev_warn_ratelimited(&dev->dev,
> + "unknown realtek protocol 0x%02x\n",
> + proto);
> + return NULL;
> + }
> +
> + /* Parse TX (switch->CPU) */
> + port = ntohs(tag[3]) & 0xf; /* Port number is the LSB 4 bits */
> + skb->dev = dsa_master_find_slave(dev, 0, port);
> + if (!skb->dev) {
> + dev_warn_ratelimited(&dev->dev,
> + "could not find slave for port %d\n",
> + port);
> + return NULL;
> + }
> +
> + /* Remove tag and recalculate checksum */
> + skb_pull_rcsum(skb, RTL8_4_TAG_LEN);
> +
> + dsa_strip_etype_header(skb, RTL8_4_TAG_LEN);
> +
> + dsa_default_offload_fwd_mark(skb);
This should not be set if the REASON is trapped to CPU.
> +
> + return skb;
> +}
