1 // SPDX-License-Identifier: GPL-2.0+
3 * net/dsa/tag_ksz.c - Microchip KSZ Switch tag format handling
4 * Copyright (c) 2017 Microchip Technology
7 #include <linux/etherdevice.h>
8 #include <linux/list.h>
9 #include <linux/slab.h>
13 /* Typically only one byte is used for tail tag. */
14 #define KSZ_EGRESS_TAG_LEN 1
15 #define KSZ_INGRESS_TAG_LEN 1
17 static struct sk_buff
*ksz_common_rcv(struct sk_buff
*skb
,
18 struct net_device
*dev
,
19 unsigned int port
, unsigned int len
)
21 skb
->dev
= dsa_master_find_slave(dev
, 0, port
);
25 pskb_trim_rcsum(skb
, skb
->len
- len
);
27 dsa_default_offload_fwd_mark(skb
);
33 * For Ingress (Host -> KSZ8795), 1 byte is added before FCS.
34 * ---------------------------------------------------------------------------
35 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag(1byte)|FCS(4bytes)
36 * ---------------------------------------------------------------------------
37 * tag : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
39 * For Egress (KSZ8795 -> Host), 1 byte is added before FCS.
40 * ---------------------------------------------------------------------------
41 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes)
42 * ---------------------------------------------------------------------------
43 * tag0 : zero-based value represents port
44 * (eg, 0x00=port1, 0x02=port3, 0x06=port7)
47 #define KSZ8795_TAIL_TAG_OVERRIDE BIT(6)
48 #define KSZ8795_TAIL_TAG_LOOKUP BIT(7)
50 static struct sk_buff
*ksz8795_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
52 struct dsa_port
*dp
= dsa_slave_to_port(dev
);
56 if (skb
->ip_summed
== CHECKSUM_PARTIAL
&& skb_checksum_help(skb
))
60 tag
= skb_put(skb
, KSZ_INGRESS_TAG_LEN
);
61 addr
= skb_mac_header(skb
);
63 *tag
= 1 << dp
->index
;
64 if (is_link_local_ether_addr(addr
))
65 *tag
|= KSZ8795_TAIL_TAG_OVERRIDE
;
70 static struct sk_buff
*ksz8795_rcv(struct sk_buff
*skb
, struct net_device
*dev
)
72 u8
*tag
= skb_tail_pointer(skb
) - KSZ_EGRESS_TAG_LEN
;
74 return ksz_common_rcv(skb
, dev
, tag
[0] & 7, KSZ_EGRESS_TAG_LEN
);
77 static const struct dsa_device_ops ksz8795_netdev_ops
= {
79 .proto
= DSA_TAG_PROTO_KSZ8795
,
82 .needed_tailroom
= KSZ_INGRESS_TAG_LEN
,
85 DSA_TAG_DRIVER(ksz8795_netdev_ops
);
86 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8795
);
89 * For Ingress (Host -> KSZ9477), 2 bytes are added before FCS.
90 * ---------------------------------------------------------------------------
91 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|tag1(1byte)|FCS(4bytes)
92 * ---------------------------------------------------------------------------
93 * tag0 : Prioritization (not used now)
94 * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
96 * For Egress (KSZ9477 -> Host), 1 byte is added before FCS.
97 * ---------------------------------------------------------------------------
98 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes)
99 * ---------------------------------------------------------------------------
100 * tag0 : zero-based value represents port
101 * (eg, 0x00=port1, 0x02=port3, 0x06=port7)
104 #define KSZ9477_INGRESS_TAG_LEN 2
105 #define KSZ9477_PTP_TAG_LEN 4
106 #define KSZ9477_PTP_TAG_INDICATION 0x80
108 #define KSZ9477_TAIL_TAG_OVERRIDE BIT(9)
109 #define KSZ9477_TAIL_TAG_LOOKUP BIT(10)
111 static struct sk_buff
*ksz9477_xmit(struct sk_buff
*skb
,
112 struct net_device
*dev
)
114 struct dsa_port
*dp
= dsa_slave_to_port(dev
);
119 if (skb
->ip_summed
== CHECKSUM_PARTIAL
&& skb_checksum_help(skb
))
123 tag
= skb_put(skb
, KSZ9477_INGRESS_TAG_LEN
);
124 addr
= skb_mac_header(skb
);
126 val
= BIT(dp
->index
);
128 if (is_link_local_ether_addr(addr
))
129 val
|= KSZ9477_TAIL_TAG_OVERRIDE
;
131 *tag
= cpu_to_be16(val
);
136 static struct sk_buff
*ksz9477_rcv(struct sk_buff
*skb
, struct net_device
*dev
)
139 u8
*tag
= skb_tail_pointer(skb
) - KSZ_EGRESS_TAG_LEN
;
140 unsigned int port
= tag
[0] & 7;
141 unsigned int len
= KSZ_EGRESS_TAG_LEN
;
143 /* Extra 4-bytes PTP timestamp */
144 if (tag
[0] & KSZ9477_PTP_TAG_INDICATION
)
145 len
+= KSZ9477_PTP_TAG_LEN
;
147 return ksz_common_rcv(skb
, dev
, port
, len
);
150 static const struct dsa_device_ops ksz9477_netdev_ops
= {
152 .proto
= DSA_TAG_PROTO_KSZ9477
,
153 .xmit
= ksz9477_xmit
,
155 .needed_tailroom
= KSZ9477_INGRESS_TAG_LEN
,
158 DSA_TAG_DRIVER(ksz9477_netdev_ops
);
159 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9477
);
161 #define KSZ9893_TAIL_TAG_OVERRIDE BIT(5)
162 #define KSZ9893_TAIL_TAG_LOOKUP BIT(6)
164 static struct sk_buff
*ksz9893_xmit(struct sk_buff
*skb
,
165 struct net_device
*dev
)
167 struct dsa_port
*dp
= dsa_slave_to_port(dev
);
171 if (skb
->ip_summed
== CHECKSUM_PARTIAL
&& skb_checksum_help(skb
))
175 tag
= skb_put(skb
, KSZ_INGRESS_TAG_LEN
);
176 addr
= skb_mac_header(skb
);
178 *tag
= BIT(dp
->index
);
180 if (is_link_local_ether_addr(addr
))
181 *tag
|= KSZ9893_TAIL_TAG_OVERRIDE
;
186 static const struct dsa_device_ops ksz9893_netdev_ops
= {
188 .proto
= DSA_TAG_PROTO_KSZ9893
,
189 .xmit
= ksz9893_xmit
,
191 .needed_tailroom
= KSZ_INGRESS_TAG_LEN
,
194 DSA_TAG_DRIVER(ksz9893_netdev_ops
);
195 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893
);
197 static struct dsa_tag_driver
*dsa_tag_driver_array
[] = {
198 &DSA_TAG_DRIVER_NAME(ksz8795_netdev_ops
),
199 &DSA_TAG_DRIVER_NAME(ksz9477_netdev_ops
),
200 &DSA_TAG_DRIVER_NAME(ksz9893_netdev_ops
),
203 module_dsa_tag_drivers(dsa_tag_driver_array
);
205 MODULE_LICENSE("GPL");