Re: [PATCH v3 3/5] net: tag: ksz: Add KSZ8863 tag code
From: Andrew Lunn <andrew@lunn.ch>
Date: 2020-05-09 16:41:09
+/* For ingress (Host -> KSZ8863), 1 byte is added before FCS.
+ * ---------------------------------------------------------------------------
+ * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|tag1(1byte)|FCS(4bytes)
+ * ---------------------------------------------------------------------------
+ * tag0[1,0] : represents port
+ * (e.g. 0b00=addr-lookup 0b01=port1, 0b10=port2, 0b11=port1+port2)
+ * tag0[3,2] : bits two and three represent prioritization
+ * (e.g. 0b00xx=prio0, 0b01xx=prio1, 0b10xx=prio2, 0b11xx=prio3)
+ *
+ * For egress (KSZ8873 -> Host), 1 byte is added before FCS.
+ * ---------------------------------------------------------------------------
+ * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes)
+ * ---------------------------------------------------------------------------
+ * tag0[0] : zero-based value represents port
+ * (eg, 0b0=port1, 0b1=port2)
+ */
+
+static struct sk_buff *ksz8863_xmit(struct sk_buff *skb,
+ struct net_device *dev)
+{
+ struct dsa_port *dp = dsa_slave_to_port(dev);
+ struct sk_buff *nskb;
+ __be16 *tag;
The comment says 1 byte is added. But tag is a u16?
Andrew