1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * net/dsa/tag_ksz.c - Microchip KSZ Switch tag format handling
4 * Copyright (c) 2017 Microchip Technology
5 */
6
7 #include <linux/etherdevice.h>
8 #include <linux/list.h>
9 #include <net/dsa.h>
10 #include "dsa_priv.h"
11
12 /* Typically only one byte is used for tail tag. */
13 #define KSZ_EGRESS_TAG_LEN 1
14 #define KSZ_INGRESS_TAG_LEN 1
15
ksz_common_rcv(struct sk_buff * skb,struct net_device * dev,unsigned int port,unsigned int len)16 static struct sk_buff *ksz_common_rcv(struct sk_buff *skb,
17 struct net_device *dev,
18 unsigned int port, unsigned int len)
19 {
20 skb->dev = dsa_master_find_slave(dev, 0, port);
21 if (!skb->dev)
22 return NULL;
23
24 if (pskb_trim_rcsum(skb, skb->len - len))
25 return NULL;
26
27 dsa_default_offload_fwd_mark(skb);
28
29 return skb;
30 }
31
32 /*
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)
38 *
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)
45 */
46
47 #define KSZ8795_TAIL_TAG_OVERRIDE BIT(6)
48 #define KSZ8795_TAIL_TAG_LOOKUP BIT(7)
49
ksz8795_xmit(struct sk_buff * skb,struct net_device * dev)50 static struct sk_buff *ksz8795_xmit(struct sk_buff *skb, struct net_device *dev)
51 {
52 struct dsa_port *dp = dsa_slave_to_port(dev);
53 u8 *tag;
54 u8 *addr;
55
56 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
57 return NULL;
58
59 /* Tag encoding */
60 tag = skb_put(skb, KSZ_INGRESS_TAG_LEN);
61 addr = skb_mac_header(skb);
62
63 *tag = 1 << dp->index;
64 if (is_link_local_ether_addr(addr))
65 *tag |= KSZ8795_TAIL_TAG_OVERRIDE;
66
67 return skb;
68 }
69
ksz8795_rcv(struct sk_buff * skb,struct net_device * dev)70 static struct sk_buff *ksz8795_rcv(struct sk_buff *skb, struct net_device *dev)
71 {
72 u8 *tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
73
74 return ksz_common_rcv(skb, dev, tag[0] & 7, KSZ_EGRESS_TAG_LEN);
75 }
76
77 static const struct dsa_device_ops ksz8795_netdev_ops = {
78 .name = "ksz8795",
79 .proto = DSA_TAG_PROTO_KSZ8795,
80 .xmit = ksz8795_xmit,
81 .rcv = ksz8795_rcv,
82 .needed_tailroom = KSZ_INGRESS_TAG_LEN,
83 };
84
85 DSA_TAG_DRIVER(ksz8795_netdev_ops);
86 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8795);
87
88 /*
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)
95 *
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)
102 */
103
104 #define KSZ9477_INGRESS_TAG_LEN 2
105 #define KSZ9477_PTP_TAG_LEN 4
106 #define KSZ9477_PTP_TAG_INDICATION 0x80
107
108 #define KSZ9477_TAIL_TAG_OVERRIDE BIT(9)
109 #define KSZ9477_TAIL_TAG_LOOKUP BIT(10)
110
ksz9477_xmit(struct sk_buff * skb,struct net_device * dev)111 static struct sk_buff *ksz9477_xmit(struct sk_buff *skb,
112 struct net_device *dev)
113 {
114 struct dsa_port *dp = dsa_slave_to_port(dev);
115 __be16 *tag;
116 u8 *addr;
117 u16 val;
118
119 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
120 return NULL;
121
122 /* Tag encoding */
123 tag = skb_put(skb, KSZ9477_INGRESS_TAG_LEN);
124 addr = skb_mac_header(skb);
125
126 val = BIT(dp->index);
127
128 if (is_link_local_ether_addr(addr))
129 val |= KSZ9477_TAIL_TAG_OVERRIDE;
130
131 *tag = cpu_to_be16(val);
132
133 return skb;
134 }
135
ksz9477_rcv(struct sk_buff * skb,struct net_device * dev)136 static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev)
137 {
138 /* Tag decoding */
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;
142
143 /* Extra 4-bytes PTP timestamp */
144 if (tag[0] & KSZ9477_PTP_TAG_INDICATION)
145 len += KSZ9477_PTP_TAG_LEN;
146
147 return ksz_common_rcv(skb, dev, port, len);
148 }
149
150 static const struct dsa_device_ops ksz9477_netdev_ops = {
151 .name = "ksz9477",
152 .proto = DSA_TAG_PROTO_KSZ9477,
153 .xmit = ksz9477_xmit,
154 .rcv = ksz9477_rcv,
155 .needed_tailroom = KSZ9477_INGRESS_TAG_LEN,
156 };
157
158 DSA_TAG_DRIVER(ksz9477_netdev_ops);
159 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9477);
160
161 #define KSZ9893_TAIL_TAG_OVERRIDE BIT(5)
162 #define KSZ9893_TAIL_TAG_LOOKUP BIT(6)
163
ksz9893_xmit(struct sk_buff * skb,struct net_device * dev)164 static struct sk_buff *ksz9893_xmit(struct sk_buff *skb,
165 struct net_device *dev)
166 {
167 struct dsa_port *dp = dsa_slave_to_port(dev);
168 u8 *addr;
169 u8 *tag;
170
171 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
172 return NULL;
173
174 /* Tag encoding */
175 tag = skb_put(skb, KSZ_INGRESS_TAG_LEN);
176 addr = skb_mac_header(skb);
177
178 *tag = BIT(dp->index);
179
180 if (is_link_local_ether_addr(addr))
181 *tag |= KSZ9893_TAIL_TAG_OVERRIDE;
182
183 return skb;
184 }
185
186 static const struct dsa_device_ops ksz9893_netdev_ops = {
187 .name = "ksz9893",
188 .proto = DSA_TAG_PROTO_KSZ9893,
189 .xmit = ksz9893_xmit,
190 .rcv = ksz9477_rcv,
191 .needed_tailroom = KSZ_INGRESS_TAG_LEN,
192 };
193
194 DSA_TAG_DRIVER(ksz9893_netdev_ops);
195 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893);
196
197 /* For xmit, 2 bytes are added before FCS.
198 * ---------------------------------------------------------------------------
199 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|tag1(1byte)|FCS(4bytes)
200 * ---------------------------------------------------------------------------
201 * tag0 : represents tag override, lookup and valid
202 * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x80=port8)
203 *
204 * For rcv, 1 byte is added before FCS.
205 * ---------------------------------------------------------------------------
206 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes)
207 * ---------------------------------------------------------------------------
208 * tag0 : zero-based value represents port
209 * (eg, 0x00=port1, 0x02=port3, 0x07=port8)
210 */
211 #define LAN937X_EGRESS_TAG_LEN 2
212
213 #define LAN937X_TAIL_TAG_BLOCKING_OVERRIDE BIT(11)
214 #define LAN937X_TAIL_TAG_LOOKUP BIT(12)
215 #define LAN937X_TAIL_TAG_VALID BIT(13)
216 #define LAN937X_TAIL_TAG_PORT_MASK 7
217
lan937x_xmit(struct sk_buff * skb,struct net_device * dev)218 static struct sk_buff *lan937x_xmit(struct sk_buff *skb,
219 struct net_device *dev)
220 {
221 struct dsa_port *dp = dsa_slave_to_port(dev);
222 const struct ethhdr *hdr = eth_hdr(skb);
223 __be16 *tag;
224 u16 val;
225
226 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
227 return NULL;
228
229 tag = skb_put(skb, LAN937X_EGRESS_TAG_LEN);
230
231 val = BIT(dp->index);
232
233 if (is_link_local_ether_addr(hdr->h_dest))
234 val |= LAN937X_TAIL_TAG_BLOCKING_OVERRIDE;
235
236 /* Tail tag valid bit - This bit should always be set by the CPU */
237 val |= LAN937X_TAIL_TAG_VALID;
238
239 put_unaligned_be16(val, tag);
240
241 return skb;
242 }
243
244 static const struct dsa_device_ops lan937x_netdev_ops = {
245 .name = "lan937x",
246 .proto = DSA_TAG_PROTO_LAN937X,
247 .xmit = lan937x_xmit,
248 .rcv = ksz9477_rcv,
249 .needed_tailroom = LAN937X_EGRESS_TAG_LEN,
250 };
251
252 DSA_TAG_DRIVER(lan937x_netdev_ops);
253 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_LAN937X);
254
255 static struct dsa_tag_driver *dsa_tag_driver_array[] = {
256 &DSA_TAG_DRIVER_NAME(ksz8795_netdev_ops),
257 &DSA_TAG_DRIVER_NAME(ksz9477_netdev_ops),
258 &DSA_TAG_DRIVER_NAME(ksz9893_netdev_ops),
259 &DSA_TAG_DRIVER_NAME(lan937x_netdev_ops),
260 };
261
262 module_dsa_tag_drivers(dsa_tag_driver_array);
263
264 MODULE_LICENSE("GPL");
265
