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 dsa_switch *ds = dp->ds; 141 struct ocelot *ocelot = ds->priv; 142 struct ocelot_port *ocelot_port; 143 u64 qos_class, rew_op; 144 u8 *injection; 145 146 if (unlikely(skb_cow_head(skb, OCELOT_TAG_LEN) < 0)) { 147 netdev_err(netdev, "Cannot make room for tag.\n"); 148 return NULL; 149 } 150 151 ocelot_port = ocelot->ports[dp->index]; 152 153 injection = skb_push(skb, OCELOT_TAG_LEN); 154 155 memcpy(injection, ocelot_port->xmit_template, OCELOT_TAG_LEN); 156 /* Fix up the fields which are not statically determined 157 * in the template 158 */ 159 qos_class = skb->priority; 160 packing(injection, &qos_class, 19, 17, OCELOT_TAG_LEN, PACK, 0); 161 162 if (ocelot->ptp && (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)) { 163 rew_op = ocelot_port->ptp_cmd; 164 if (ocelot_port->ptp_cmd == IFH_REW_OP_TWO_STEP_PTP) { 165 rew_op |= (ocelot_port->ts_id % 4) << 3; 166 ocelot_port->ts_id++; 167 } 168 169 packing(injection, &rew_op, 125, 117, OCELOT_TAG_LEN, PACK, 0); 170 } 171 172 return skb; 173 } 174 175 static struct sk_buff *ocelot_rcv(struct sk_buff *skb, 176 struct net_device *netdev, 177 struct packet_type *pt) 178 { 179 u64 src_port, qos_class; 180 u8 *start = skb->data; 181 u8 *extraction; 182 183 /* Revert skb->data by the amount consumed by the DSA master, 184 * so it points to the beginning of the frame. 185 */ 186 skb_push(skb, ETH_HLEN); 187 /* We don't care about the long prefix, it is just for easy entrance 188 * into the DSA master's RX filter. Discard it now by moving it into 189 * the headroom. 190 */ 191 skb_pull(skb, OCELOT_LONG_PREFIX_LEN); 192 /* And skb->data now points to the extraction frame header. 193 * Keep a pointer to it. 194 */ 195 extraction = skb->data; 196 /* Now the EFH is part of the headroom as well */ 197 skb_pull(skb, OCELOT_TAG_LEN); 198 /* Reset the pointer to the real MAC header */ 199 skb_reset_mac_header(skb); 200 skb_reset_mac_len(skb); 201 /* And move skb->data to the correct location again */ 202 skb_pull(skb, ETH_HLEN); 203 204 /* Remove from inet csum the extraction header */ 205 skb_postpull_rcsum(skb, start, OCELOT_LONG_PREFIX_LEN + OCELOT_TAG_LEN); 206 207 packing(extraction, &src_port, 46, 43, OCELOT_TAG_LEN, UNPACK, 0); 208 packing(extraction, &qos_class, 19, 17, OCELOT_TAG_LEN, UNPACK, 0); 209 210 skb->dev = dsa_master_find_slave(netdev, 0, src_port); 211 if (!skb->dev) 212 /* The switch will reflect back some frames sent through 213 * sockets opened on the bare DSA master. These will come back 214 * with src_port equal to the index of the CPU port, for which 215 * there is no slave registered. So don't print any error 216 * message here (ignore and drop those frames). 217 */ 218 return NULL; 219 220 skb->offload_fwd_mark = 1; 221 skb->priority = qos_class; 222 223 return skb; 224 } 225 226 static const struct dsa_device_ops ocelot_netdev_ops = { 227 .name = "ocelot", 228 .proto = DSA_TAG_PROTO_OCELOT, 229 .xmit = ocelot_xmit, 230 .rcv = ocelot_rcv, 231 .overhead = OCELOT_TAG_LEN + OCELOT_LONG_PREFIX_LEN, 232 }; 233 234 MODULE_LICENSE("GPL v2"); 235 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT); 236 237 module_dsa_tag_driver(ocelot_netdev_ops); 238