net/dsa/tag

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
ksz_common_xmit
ksz_common_rcv
ksz8795_xmit
ksz8795_rcv
ksz9477_xmit
ksz9477_rcv
ksz9893_xmit
   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 <linux/slab.h>
  10 #include <net/dsa.h>
  11 #include "dsa_priv.h"
  12 
  13 /* Typically only one byte is used for tail tag. */
  14 #define KSZ_EGRESS_TAG_LEN              1
  15 #define KSZ_INGRESS_TAG_LEN             1
  16 
  17 static struct sk_buff *ksz_common_xmit(struct sk_buff *skb,
  18                                        struct net_device *dev, int len)
  19 {
  20         struct sk_buff *nskb;
  21         int padlen;
  22 
  23         padlen = (skb->len >= ETH_ZLEN) ? 0 : ETH_ZLEN - skb->len;
  24 
  25         if (skb_tailroom(skb) >= padlen + len) {
  26                 /* Let dsa_slave_xmit() free skb */
  27                 if (__skb_put_padto(skb, skb->len + padlen, false))
  28                         return NULL;
  29 
  30                 nskb = skb;
  31         } else {
  32                 nskb = alloc_skb(NET_IP_ALIGN + skb->len +
  33                                  padlen + len, GFP_ATOMIC);
  34                 if (!nskb)
  35                         return NULL;
  36                 skb_reserve(nskb, NET_IP_ALIGN);
  37 
  38                 skb_reset_mac_header(nskb);
  39                 skb_set_network_header(nskb,
  40                                        skb_network_header(skb) - skb->head);
  41                 skb_set_transport_header(nskb,
  42                                          skb_transport_header(skb) - skb->head);
  43                 skb_copy_and_csum_dev(skb, skb_put(nskb, skb->len));
  44 
  45                 /* Let skb_put_padto() free nskb, and let dsa_slave_xmit() free
  46                  * skb
  47                  */
  48                 if (skb_put_padto(nskb, nskb->len + padlen))
  49                         return NULL;
  50 
  51                 consume_skb(skb);
  52         }
  53 
  54         return nskb;
  55 }
  56 
  57 static struct sk_buff *ksz_common_rcv(struct sk_buff *skb,
  58                                       struct net_device *dev,
  59                                       unsigned int port, unsigned int len)
  60 {
  61         skb->dev = dsa_master_find_slave(dev, 0, port);
  62         if (!skb->dev)
  63                 return NULL;
  64 
  65         pskb_trim_rcsum(skb, skb->len - len);
  66 
  67         skb->offload_fwd_mark = true;
  68 
  69         return skb;
  70 }
  71 
  72 /*
  73  * For Ingress (Host -> KSZ8795), 1 byte is added before FCS.
  74  * ---------------------------------------------------------------------------
  75  * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag(1byte)|FCS(4bytes)
  76  * ---------------------------------------------------------------------------
  77  * tag : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
  78  *
  79  * For Egress (KSZ8795 -> Host), 1 byte is added before FCS.
  80  * ---------------------------------------------------------------------------
  81  * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes)
  82  * ---------------------------------------------------------------------------
  83  * tag0 : zero-based value represents port
  84  *        (eg, 0x00=port1, 0x02=port3, 0x06=port7)
  85  */
  86 
  87 #define KSZ8795_INGRESS_TAG_LEN         1
  88 
  89 #define KSZ8795_TAIL_TAG_OVERRIDE       BIT(6)
  90 #define KSZ8795_TAIL_TAG_LOOKUP         BIT(7)
  91 
  92 static struct sk_buff *ksz8795_xmit(struct sk_buff *skb, struct net_device *dev)
  93 {
  94         struct dsa_port *dp = dsa_slave_to_port(dev);
  95         struct sk_buff *nskb;
  96         u8 *tag;
  97         u8 *addr;
  98 
  99         nskb = ksz_common_xmit(skb, dev, KSZ8795_INGRESS_TAG_LEN);
 100         if (!nskb)
 101                 return NULL;
 102 
 103         /* Tag encoding */
 104         tag = skb_put(nskb, KSZ8795_INGRESS_TAG_LEN);
 105         addr = skb_mac_header(nskb);
 106 
 107         *tag = 1 << dp->index;
 108         if (is_link_local_ether_addr(addr))
 109                 *tag |= KSZ8795_TAIL_TAG_OVERRIDE;
 110 
 111         return nskb;
 112 }
 113 
 114 static struct sk_buff *ksz8795_rcv(struct sk_buff *skb, struct net_device *dev,
 115                                   struct packet_type *pt)
 116 {
 117         u8 *tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
 118 
 119         return ksz_common_rcv(skb, dev, tag[0] & 7, KSZ_EGRESS_TAG_LEN);
 120 }
 121 
 122 static const struct dsa_device_ops ksz8795_netdev_ops = {
 123         .name   = "ksz8795",
 124         .proto  = DSA_TAG_PROTO_KSZ8795,
 125         .xmit   = ksz8795_xmit,
 126         .rcv    = ksz8795_rcv,
 127         .overhead = KSZ8795_INGRESS_TAG_LEN,
 128 };
 129 
 130 DSA_TAG_DRIVER(ksz8795_netdev_ops);
 131 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8795);
 132 
 133 /*
 134  * For Ingress (Host -> KSZ9477), 2 bytes are added before FCS.
 135  * ---------------------------------------------------------------------------
 136  * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|tag1(1byte)|FCS(4bytes)
 137  * ---------------------------------------------------------------------------
 138  * tag0 : Prioritization (not used now)
 139  * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
 140  *
 141  * For Egress (KSZ9477 -> Host), 1 byte is added before FCS.
 142  * ---------------------------------------------------------------------------
 143  * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes)
 144  * ---------------------------------------------------------------------------
 145  * tag0 : zero-based value represents port
 146  *        (eg, 0x00=port1, 0x02=port3, 0x06=port7)
 147  */
 148 
 149 #define KSZ9477_INGRESS_TAG_LEN         2
 150 #define KSZ9477_PTP_TAG_LEN             4
 151 #define KSZ9477_PTP_TAG_INDICATION      0x80
 152 
 153 #define KSZ9477_TAIL_TAG_OVERRIDE       BIT(9)
 154 #define KSZ9477_TAIL_TAG_LOOKUP         BIT(10)
 155 
 156 static struct sk_buff *ksz9477_xmit(struct sk_buff *skb,
 157                                     struct net_device *dev)
 158 {
 159         struct dsa_port *dp = dsa_slave_to_port(dev);
 160         struct sk_buff *nskb;
 161         u16 *tag;
 162         u8 *addr;
 163 
 164         nskb = ksz_common_xmit(skb, dev, KSZ9477_INGRESS_TAG_LEN);
 165         if (!nskb)
 166                 return NULL;
 167 
 168         /* Tag encoding */
 169         tag = skb_put(nskb, KSZ9477_INGRESS_TAG_LEN);
 170         addr = skb_mac_header(nskb);
 171 
 172         *tag = BIT(dp->index);
 173 
 174         if (is_link_local_ether_addr(addr))
 175                 *tag |= KSZ9477_TAIL_TAG_OVERRIDE;
 176 
 177         *tag = cpu_to_be16(*tag);
 178 
 179         return nskb;
 180 }
 181 
 182 static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev,
 183                                    struct packet_type *pt)
 184 {
 185         /* Tag decoding */
 186         u8 *tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
 187         unsigned int port = tag[0] & 7;
 188         unsigned int len = KSZ_EGRESS_TAG_LEN;
 189 
 190         /* Extra 4-bytes PTP timestamp */
 191         if (tag[0] & KSZ9477_PTP_TAG_INDICATION)
 192                 len += KSZ9477_PTP_TAG_LEN;
 193 
 194         return ksz_common_rcv(skb, dev, port, len);
 195 }
 196 
 197 static const struct dsa_device_ops ksz9477_netdev_ops = {
 198         .name   = "ksz9477",
 199         .proto  = DSA_TAG_PROTO_KSZ9477,
 200         .xmit   = ksz9477_xmit,
 201         .rcv    = ksz9477_rcv,
 202         .overhead = KSZ9477_INGRESS_TAG_LEN,
 203 };
 204 
 205 DSA_TAG_DRIVER(ksz9477_netdev_ops);
 206 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9477);
 207 
 208 #define KSZ9893_TAIL_TAG_OVERRIDE       BIT(5)
 209 #define KSZ9893_TAIL_TAG_LOOKUP         BIT(6)
 210 
 211 static struct sk_buff *ksz9893_xmit(struct sk_buff *skb,
 212                                     struct net_device *dev)
 213 {
 214         struct dsa_port *dp = dsa_slave_to_port(dev);
 215         struct sk_buff *nskb;
 216         u8 *addr;
 217         u8 *tag;
 218 
 219         nskb = ksz_common_xmit(skb, dev, KSZ_INGRESS_TAG_LEN);
 220         if (!nskb)
 221                 return NULL;
 222 
 223         /* Tag encoding */
 224         tag = skb_put(nskb, KSZ_INGRESS_TAG_LEN);
 225         addr = skb_mac_header(nskb);
 226 
 227         *tag = BIT(dp->index);
 228 
 229         if (is_link_local_ether_addr(addr))
 230                 *tag |= KSZ9893_TAIL_TAG_OVERRIDE;
 231 
 232         return nskb;
 233 }
 234 
 235 static const struct dsa_device_ops ksz9893_netdev_ops = {
 236         .name   = "ksz9893",
 237         .proto  = DSA_TAG_PROTO_KSZ9893,
 238         .xmit   = ksz9893_xmit,
 239         .rcv    = ksz9477_rcv,
 240         .overhead = KSZ_INGRESS_TAG_LEN,
 241 };
 242 
 243 DSA_TAG_DRIVER(ksz9893_netdev_ops);
 244 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893);
 245 
 246 static struct dsa_tag_driver *dsa_tag_driver_array[] = {
 247         &DSA_TAG_DRIVER_NAME(ksz8795_netdev_ops),
 248         &DSA_TAG_DRIVER_NAME(ksz9477_netdev_ops),
 249         &DSA_TAG_DRIVER_NAME(ksz9893_netdev_ops),
 250 };
 251 
 252 module_dsa_tag_drivers(dsa_tag_driver_array);
 253 
 254 MODULE_LICENSE("GPL");
/* [<][>][^][v][top][bottom][index][help] */
root/net/dsa/tag_ksz.c

DEFINITIONS
