1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright 2019 NXP Semiconductors 3 */ 4 #include <soc/mscc/ocelot.h> 5 #include <linux/packing.h> 6 #include "dsa_priv.h" 7 8 /* The CPU injection header and the CPU extraction header can have 3 types of 9 * prefixes: long, short and no prefix. The format of the header itself is the 10 * same in all 3 cases. 11 * 12 * Extraction with long prefix: 13 * 14 * +-------------------+-------------------+------+------+------------+-------+ 15 * | ff:ff:ff:ff:ff:ff | ff:ff:ff:ff:ff:ff | 8880 | 000a | extraction | frame | 16 * | | | | | header | | 17 * +-------------------+-------------------+------+------+------------+-------+ 18 * 48 bits 48 bits 16 bits 16 bits 128 bits 19 * 20 * Extraction with short prefix: 21 * 22 * +------+------+------------+-------+ 23 * | 8880 | 000a | extraction | frame | 24 * | | | header | | 25 * +------+------+------------+-------+ 26 * 16 bits 16 bits 128 bits 27 * 28 * Extraction with no prefix: 29 * 30 * +------------+-------+ 31 * | extraction | frame | 32 * | header | | 33 * +------------+-------+ 34 * 128 bits 35 * 36 * 37 * Injection with long prefix: 38 * 39 * +-------------------+-------------------+------+------+------------+-------+ 40 * | any dmac | any smac | 8880 | 000a | injection | frame | 41 * | | | | | header | | 42 * +-------------------+-------------------+------+------+------------+-------+ 43 * 48 bits 48 bits 16 bits 16 bits 128 bits 44 * 45 * Injection with short prefix: 46 * 47 * +------+------+------------+-------+ 48 * | 8880 | 000a | injection | frame | 49 * | | | header | | 50 * +------+------+------------+-------+ 51 * 16 bits 16 bits 128 bits 52 * 53 * Injection with no prefix: 54 * 55 * +------------+-------+ 56 * | injection | frame | 57 * | header | | 58 * +------------+-------+ 59 * 128 bits 60 * 61 * The injection header looks like this (network byte order, bit 127 62 * is part of lowest address byte in memory, bit 0 is part of highest 63 * address byte): 64 * 65 * +------+------+------+------+------+------+------+------+ 66 * 127:120 |BYPASS| MASQ | MASQ_PORT |REW_OP|REW_OP| 67 * +------+------+------+------+------+------+------+------+ 68 * 119:112 | REW_OP | 69 * +------+------+------+------+------+------+------+------+ 70 * 111:104 | REW_VAL | 71 * +------+------+------+------+------+------+------+------+ 72 * 103: 96 | REW_VAL | 73 * +------+------+------+------+------+------+------+------+ 74 * 95: 88 | REW_VAL | 75 * +------+------+------+------+------+------+------+------+ 76 * 87: 80 | REW_VAL | 77 * +------+------+------+------+------+------+------+------+ 78 * 79: 72 | RSV | 79 * +------+------+------+------+------+------+------+------+ 80 * 71: 64 | RSV | DEST | 81 * +------+------+------+------+------+------+------+------+ 82 * 63: 56 | DEST | 83 * +------+------+------+------+------+------+------+------+ 84 * 55: 48 | RSV | 85 * +------+------+------+------+------+------+------+------+ 86 * 47: 40 | RSV | SRC_PORT | RSV |TFRM_TIMER| 87 * +------+------+------+------+------+------+------+------+ 88 * 39: 32 | TFRM_TIMER | RSV | 89 * +------+------+------+------+------+------+------+------+ 90 * 31: 24 | RSV | DP | POP_CNT | CPUQ | 91 * +------+------+------+------+------+------+------+------+ 92 * 23: 16 | CPUQ | QOS_CLASS |TAG_TYPE| 93 * +------+------+------+------+------+------+------+------+ 94 * 15: 8 | PCP | DEI | VID | 95 * +------+------+------+------+------+------+------+------+ 96 * 7: 0 | VID | 97 * +------+------+------+------+------+------+------+------+ 98 * 99 * And the extraction header looks like this: 100 * 101 * +------+------+------+------+------+------+------+------+ 102 * 127:120 | RSV | REW_OP | 103 * +------+------+------+------+------+------+------+------+ 104 * 119:112 | REW_OP | REW_VAL | 105 * +------+------+------+------+------+------+------+------+ 106 * 111:104 | REW_VAL | 107 * +------+------+------+------+------+------+------+------+ 108 * 103: 96 | REW_VAL | 109 * +------+------+------+------+------+------+------+------+ 110 * 95: 88 | REW_VAL | 111 * +------+------+------+------+------+------+------+------+ 112 * 87: 80 | REW_VAL | LLEN | 113 * +------+------+------+------+------+------+------+------+ 114 * 79: 72 | LLEN | WLEN | 115 * +------+------+------+------+------+------+------+------+ 116 * 71: 64 | WLEN | RSV | 117 * +------+------+------+------+------+------+------+------+ 118 * 63: 56 | RSV | 119 * +------+------+------+------+------+------+------+------+ 120 * 55: 48 | RSV | 121 * +------+------+------+------+------+------+------+------+ 122 * 47: 40 | RSV | SRC_PORT | ACL_ID | 123 * +------+------+------+------+------+------+------+------+ 124 * 39: 32 | ACL_ID | RSV | SFLOW_ID | 125 * +------+------+------+------+------+------+------+------+ 126 * 31: 24 |ACL_HIT| DP | LRN_FLAGS | CPUQ | 127 * +------+------+------+------+------+------+------+------+ 128 * 23: 16 | CPUQ | QOS_CLASS |TAG_TYPE| 129 * +------+------+------+------+------+------+------+------+ 130 * 15: 8 | PCP | DEI | VID | 131 * +------+------+------+------+------+------+------+------+ 132 * 7: 0 | VID | 133 * +------+------+------+------+------+------+------+------+ 134 */ 135 136 static struct sk_buff *ocelot_xmit(struct sk_buff *skb, 137 struct net_device *netdev) 138 { 139 struct dsa_port *dp = dsa_slave_to_port(netdev); 140 struct sk_buff *clone = DSA_SKB_CB(skb)->clone; 141 struct dsa_switch *ds = dp->ds; 142 struct ocelot *ocelot = ds->priv; 143 struct ocelot_port *ocelot_port; 144 u8 *prefix, *injection; 145 u64 qos_class, rew_op; 146 int err; 147 148 err = skb_cow_head(skb, OCELOT_TOTAL_TAG_LEN); 149 if (unlikely(err < 0)) { 150 netdev_err(netdev, "Cannot make room for tag.\n"); 151 return NULL; 152 } 153 154 ocelot_port = ocelot->ports[dp->index]; 155 156 injection = skb_push(skb, OCELOT_TAG_LEN); 157 158 prefix = skb_push(skb, OCELOT_SHORT_PREFIX_LEN); 159 160 memcpy(prefix, ocelot_port->xmit_template, OCELOT_TOTAL_TAG_LEN); 161 162 /* Fix up the fields which are not statically determined 163 * in the template 164 */ 165 qos_class = skb->priority; 166 packing(injection, &qos_class, 19, 17, OCELOT_TAG_LEN, PACK, 0); 167 168 /* TX timestamping was requested */ 169 if (clone) { 170 rew_op = ocelot_port->ptp_cmd; 171 /* Retrieve timestamp ID populated inside skb->cb[0] of the 172 * clone by ocelot_port_add_txtstamp_skb 173 */ 174 if (ocelot_port->ptp_cmd == IFH_REW_OP_TWO_STEP_PTP) 175 rew_op |= clone->cb[0] << 3; 176 177 packing(injection, &rew_op, 125, 117, OCELOT_TAG_LEN, PACK, 0); 178 } 179 180 return skb; 181 } 182 183 static struct sk_buff *ocelot_rcv(struct sk_buff *skb, 184 struct net_device *netdev, 185 struct packet_type *pt) 186 { 187 struct dsa_port *cpu_dp = netdev->dsa_ptr; 188 struct dsa_switch *ds = cpu_dp->ds; 189 struct ocelot *ocelot = ds->priv; 190 u64 src_port, qos_class; 191 u64 vlan_tci, tag_type; 192 u8 *start = skb->data; 193 u8 *extraction; 194 u16 vlan_tpid; 195 196 /* Revert skb->data by the amount consumed by the DSA master, 197 * so it points to the beginning of the frame. 198 */ 199 skb_push(skb, ETH_HLEN); 200 /* We don't care about the short prefix, it is just for easy entrance 201 * into the DSA master's RX filter. Discard it now by moving it into 202 * the headroom. 203 */ 204 skb_pull(skb, OCELOT_SHORT_PREFIX_LEN); 205 /* And skb->data now points to the extraction frame header. 206 * Keep a pointer to it. 207 */ 208 extraction = skb->data; 209 /* Now the EFH is part of the headroom as well */ 210 skb_pull(skb, OCELOT_TAG_LEN); 211 /* Reset the pointer to the real MAC header */ 212 skb_reset_mac_header(skb); 213 skb_reset_mac_len(skb); 214 /* And move skb->data to the correct location again */ 215 skb_pull(skb, ETH_HLEN); 216 217 /* Remove from inet csum the extraction header */ 218 skb_postpull_rcsum(skb, start, OCELOT_TOTAL_TAG_LEN); 219 220 packing(extraction, &src_port, 46, 43, OCELOT_TAG_LEN, UNPACK, 0); 221 packing(extraction, &qos_class, 19, 17, OCELOT_TAG_LEN, UNPACK, 0); 222 packing(extraction, &tag_type, 16, 16, OCELOT_TAG_LEN, UNPACK, 0); 223 packing(extraction, &vlan_tci, 15, 0, OCELOT_TAG_LEN, UNPACK, 0); 224 225 skb->dev = dsa_master_find_slave(netdev, 0, src_port); 226 if (!skb->dev) 227 /* The switch will reflect back some frames sent through 228 * sockets opened on the bare DSA master. These will come back 229 * with src_port equal to the index of the CPU port, for which 230 * there is no slave registered. So don't print any error 231 * message here (ignore and drop those frames). 232 */ 233 return NULL; 234 235 skb->offload_fwd_mark = 1; 236 skb->priority = qos_class; 237 238 /* Ocelot switches copy frames unmodified to the CPU. However, it is 239 * possible for the user to request a VLAN modification through 240 * VCAP_IS1_ACT_VID_REPLACE_ENA. In this case, what will happen is that 241 * the VLAN ID field from the Extraction Header gets updated, but the 242 * 802.1Q header does not (the classified VLAN only becomes visible on 243 * egress through the "port tag" of front-panel ports). 244 * So, for traffic extracted by the CPU, we want to pick up the 245 * classified VLAN and manually replace the existing 802.1Q header from 246 * the packet with it, so that the operating system is always up to 247 * date with the result of tc-vlan actions. 248 * NOTE: In VLAN-unaware mode, we don't want to do that, we want the 249 * frame to remain unmodified, because the classified VLAN is always 250 * equal to the pvid of the ingress port and should not be used for 251 * processing. 252 */ 253 vlan_tpid = tag_type ? ETH_P_8021AD : ETH_P_8021Q; 254 255 if (ocelot->ports[src_port]->vlan_aware && 256 eth_hdr(skb)->h_proto == htons(vlan_tpid)) { 257 u16 dummy_vlan_tci; 258 259 skb_push_rcsum(skb, ETH_HLEN); 260 __skb_vlan_pop(skb, &dummy_vlan_tci); 261 skb_pull_rcsum(skb, ETH_HLEN); 262 __vlan_hwaccel_put_tag(skb, htons(vlan_tpid), vlan_tci); 263 } 264 265 return skb; 266 } 267 268 static const struct dsa_device_ops ocelot_netdev_ops = { 269 .name = "ocelot", 270 .proto = DSA_TAG_PROTO_OCELOT, 271 .xmit = ocelot_xmit, 272 .rcv = ocelot_rcv, 273 .overhead = OCELOT_TOTAL_TAG_LEN, 274 .promisc_on_master = true, 275 }; 276 277 MODULE_LICENSE("GPL v2"); 278 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT); 279 280 module_dsa_tag_driver(ocelot_netdev_ops); 281