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 11 #include "tag.h" 12 13 #define KSZ8795_NAME "ksz8795" 14 #define KSZ9477_NAME "ksz9477" 15 #define KSZ9893_NAME "ksz9893" 16 #define LAN937X_NAME "lan937x" 17 18 /* Typically only one byte is used for tail tag. */ 19 #define KSZ_EGRESS_TAG_LEN 1 20 #define KSZ_INGRESS_TAG_LEN 1 21 22 static struct sk_buff *ksz_common_rcv(struct sk_buff *skb, 23 struct net_device *dev, 24 unsigned int port, unsigned int len) 25 { 26 skb->dev = dsa_master_find_slave(dev, 0, port); 27 if (!skb->dev) 28 return NULL; 29 30 if (pskb_trim_rcsum(skb, skb->len - len)) 31 return NULL; 32 33 dsa_default_offload_fwd_mark(skb); 34 35 return skb; 36 } 37 38 /* 39 * For Ingress (Host -> KSZ8795), 1 byte is added before FCS. 40 * --------------------------------------------------------------------------- 41 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag(1byte)|FCS(4bytes) 42 * --------------------------------------------------------------------------- 43 * tag : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5) 44 * 45 * For Egress (KSZ8795 -> Host), 1 byte is added before FCS. 46 * --------------------------------------------------------------------------- 47 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes) 48 * --------------------------------------------------------------------------- 49 * tag0 : zero-based value represents port 50 * (eg, 0x00=port1, 0x02=port3, 0x06=port7) 51 */ 52 53 #define KSZ8795_TAIL_TAG_OVERRIDE BIT(6) 54 #define KSZ8795_TAIL_TAG_LOOKUP BIT(7) 55 56 static struct sk_buff *ksz8795_xmit(struct sk_buff *skb, struct net_device *dev) 57 { 58 struct dsa_port *dp = dsa_slave_to_port(dev); 59 u8 *tag; 60 u8 *addr; 61 62 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb)) 63 return NULL; 64 65 /* Tag encoding */ 66 tag = skb_put(skb, KSZ_INGRESS_TAG_LEN); 67 addr = skb_mac_header(skb); 68 69 *tag = 1 << dp->index; 70 if (is_link_local_ether_addr(addr)) 71 *tag |= KSZ8795_TAIL_TAG_OVERRIDE; 72 73 return skb; 74 } 75 76 static struct sk_buff *ksz8795_rcv(struct sk_buff *skb, struct net_device *dev) 77 { 78 u8 *tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN; 79 80 return ksz_common_rcv(skb, dev, tag[0] & 7, KSZ_EGRESS_TAG_LEN); 81 } 82 83 static const struct dsa_device_ops ksz8795_netdev_ops = { 84 .name = KSZ8795_NAME, 85 .proto = DSA_TAG_PROTO_KSZ8795, 86 .xmit = ksz8795_xmit, 87 .rcv = ksz8795_rcv, 88 .needed_tailroom = KSZ_INGRESS_TAG_LEN, 89 }; 90 91 DSA_TAG_DRIVER(ksz8795_netdev_ops); 92 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8795, KSZ8795_NAME); 93 94 /* 95 * For Ingress (Host -> KSZ9477), 2 bytes are added before FCS. 96 * --------------------------------------------------------------------------- 97 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|tag1(1byte)|FCS(4bytes) 98 * --------------------------------------------------------------------------- 99 * tag0 : Prioritization (not used now) 100 * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5) 101 * 102 * For Egress (KSZ9477 -> Host), 1 byte is added before FCS. 103 * --------------------------------------------------------------------------- 104 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes) 105 * --------------------------------------------------------------------------- 106 * tag0 : zero-based value represents port 107 * (eg, 0x00=port1, 0x02=port3, 0x06=port7) 108 */ 109 110 #define KSZ9477_INGRESS_TAG_LEN 2 111 #define KSZ9477_PTP_TAG_LEN 4 112 #define KSZ9477_PTP_TAG_INDICATION 0x80 113 114 #define KSZ9477_TAIL_TAG_OVERRIDE BIT(9) 115 #define KSZ9477_TAIL_TAG_LOOKUP BIT(10) 116 117 static struct sk_buff *ksz9477_xmit(struct sk_buff *skb, 118 struct net_device *dev) 119 { 120 struct dsa_port *dp = dsa_slave_to_port(dev); 121 __be16 *tag; 122 u8 *addr; 123 u16 val; 124 125 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb)) 126 return NULL; 127 128 /* Tag encoding */ 129 tag = skb_put(skb, KSZ9477_INGRESS_TAG_LEN); 130 addr = skb_mac_header(skb); 131 132 val = BIT(dp->index); 133 134 if (is_link_local_ether_addr(addr)) 135 val |= KSZ9477_TAIL_TAG_OVERRIDE; 136 137 *tag = cpu_to_be16(val); 138 139 return skb; 140 } 141 142 static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev) 143 { 144 /* Tag decoding */ 145 u8 *tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN; 146 unsigned int port = tag[0] & 7; 147 unsigned int len = KSZ_EGRESS_TAG_LEN; 148 149 /* Extra 4-bytes PTP timestamp */ 150 if (tag[0] & KSZ9477_PTP_TAG_INDICATION) 151 len += KSZ9477_PTP_TAG_LEN; 152 153 return ksz_common_rcv(skb, dev, port, len); 154 } 155 156 static const struct dsa_device_ops ksz9477_netdev_ops = { 157 .name = KSZ9477_NAME, 158 .proto = DSA_TAG_PROTO_KSZ9477, 159 .xmit = ksz9477_xmit, 160 .rcv = ksz9477_rcv, 161 .needed_tailroom = KSZ9477_INGRESS_TAG_LEN, 162 }; 163 164 DSA_TAG_DRIVER(ksz9477_netdev_ops); 165 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9477, KSZ9477_NAME); 166 167 #define KSZ9893_TAIL_TAG_OVERRIDE BIT(5) 168 #define KSZ9893_TAIL_TAG_LOOKUP BIT(6) 169 170 static struct sk_buff *ksz9893_xmit(struct sk_buff *skb, 171 struct net_device *dev) 172 { 173 struct dsa_port *dp = dsa_slave_to_port(dev); 174 u8 *addr; 175 u8 *tag; 176 177 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb)) 178 return NULL; 179 180 /* Tag encoding */ 181 tag = skb_put(skb, KSZ_INGRESS_TAG_LEN); 182 addr = skb_mac_header(skb); 183 184 *tag = BIT(dp->index); 185 186 if (is_link_local_ether_addr(addr)) 187 *tag |= KSZ9893_TAIL_TAG_OVERRIDE; 188 189 return skb; 190 } 191 192 static const struct dsa_device_ops ksz9893_netdev_ops = { 193 .name = KSZ9893_NAME, 194 .proto = DSA_TAG_PROTO_KSZ9893, 195 .xmit = ksz9893_xmit, 196 .rcv = ksz9477_rcv, 197 .needed_tailroom = KSZ_INGRESS_TAG_LEN, 198 }; 199 200 DSA_TAG_DRIVER(ksz9893_netdev_ops); 201 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893, KSZ9893_NAME); 202 203 /* For xmit, 2 bytes are added before FCS. 204 * --------------------------------------------------------------------------- 205 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|tag1(1byte)|FCS(4bytes) 206 * --------------------------------------------------------------------------- 207 * tag0 : represents tag override, lookup and valid 208 * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x80=port8) 209 * 210 * For rcv, 1 byte is added before FCS. 211 * --------------------------------------------------------------------------- 212 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes) 213 * --------------------------------------------------------------------------- 214 * tag0 : zero-based value represents port 215 * (eg, 0x00=port1, 0x02=port3, 0x07=port8) 216 */ 217 #define LAN937X_EGRESS_TAG_LEN 2 218 219 #define LAN937X_TAIL_TAG_BLOCKING_OVERRIDE BIT(11) 220 #define LAN937X_TAIL_TAG_LOOKUP BIT(12) 221 #define LAN937X_TAIL_TAG_VALID BIT(13) 222 #define LAN937X_TAIL_TAG_PORT_MASK 7 223 224 static struct sk_buff *lan937x_xmit(struct sk_buff *skb, 225 struct net_device *dev) 226 { 227 struct dsa_port *dp = dsa_slave_to_port(dev); 228 const struct ethhdr *hdr = eth_hdr(skb); 229 __be16 *tag; 230 u16 val; 231 232 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb)) 233 return NULL; 234 235 tag = skb_put(skb, LAN937X_EGRESS_TAG_LEN); 236 237 val = BIT(dp->index); 238 239 if (is_link_local_ether_addr(hdr->h_dest)) 240 val |= LAN937X_TAIL_TAG_BLOCKING_OVERRIDE; 241 242 /* Tail tag valid bit - This bit should always be set by the CPU */ 243 val |= LAN937X_TAIL_TAG_VALID; 244 245 put_unaligned_be16(val, tag); 246 247 return skb; 248 } 249 250 static const struct dsa_device_ops lan937x_netdev_ops = { 251 .name = LAN937X_NAME, 252 .proto = DSA_TAG_PROTO_LAN937X, 253 .xmit = lan937x_xmit, 254 .rcv = ksz9477_rcv, 255 .needed_tailroom = LAN937X_EGRESS_TAG_LEN, 256 }; 257 258 DSA_TAG_DRIVER(lan937x_netdev_ops); 259 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_LAN937X, LAN937X_NAME); 260 261 static struct dsa_tag_driver *dsa_tag_driver_array[] = { 262 &DSA_TAG_DRIVER_NAME(ksz8795_netdev_ops), 263 &DSA_TAG_DRIVER_NAME(ksz9477_netdev_ops), 264 &DSA_TAG_DRIVER_NAME(ksz9893_netdev_ops), 265 &DSA_TAG_DRIVER_NAME(lan937x_netdev_ops), 266 }; 267 268 module_dsa_tag_drivers(dsa_tag_driver_array); 269 270 MODULE_LICENSE("GPL"); 271