| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * net/dsa/tag_ksz.c - Microchip KSZ Switch tag format handling |
| * Copyright (c) 2017 Microchip Technology |
| */ |
| |
| #include <linux/etherdevice.h> |
| #include <linux/list.h> |
| #include <linux/slab.h> |
| #include <net/dsa.h> |
| #include "dsa_priv.h" |
| |
| /* Typically only one byte is used for tail tag. */ |
| #define KSZ_EGRESS_TAG_LEN 1 |
| #define KSZ_INGRESS_TAG_LEN 1 |
| |
| static struct sk_buff *ksz_common_rcv(struct sk_buff *skb, |
| struct net_device *dev, |
| unsigned int port, unsigned int len) |
| { |
| skb->dev = dsa_master_find_slave(dev, 0, port); |
| if (!skb->dev) |
| return NULL; |
| |
| pskb_trim_rcsum(skb, skb->len - len); |
| |
| dsa_default_offload_fwd_mark(skb); |
| |
| return skb; |
| } |
| |
| /* |
| * For Ingress (Host -> KSZ8795), 1 byte is added before FCS. |
| * --------------------------------------------------------------------------- |
| * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag(1byte)|FCS(4bytes) |
| * --------------------------------------------------------------------------- |
| * tag : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5) |
| * |
| * For Egress (KSZ8795 -> Host), 1 byte is added before FCS. |
| * --------------------------------------------------------------------------- |
| * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes) |
| * --------------------------------------------------------------------------- |
| * tag0 : zero-based value represents port |
| * (eg, 0x00=port1, 0x02=port3, 0x06=port7) |
| */ |
| |
| #define KSZ8795_TAIL_TAG_OVERRIDE BIT(6) |
| #define KSZ8795_TAIL_TAG_LOOKUP BIT(7) |
| |
| static struct sk_buff *ksz8795_xmit(struct sk_buff *skb, struct net_device *dev) |
| { |
| struct dsa_port *dp = dsa_slave_to_port(dev); |
| u8 *tag; |
| u8 *addr; |
| |
| if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb)) |
| return NULL; |
| |
| /* Tag encoding */ |
| tag = skb_put(skb, KSZ_INGRESS_TAG_LEN); |
| addr = skb_mac_header(skb); |
| |
| *tag = 1 << dp->index; |
| if (is_link_local_ether_addr(addr)) |
| *tag |= KSZ8795_TAIL_TAG_OVERRIDE; |
| |
| return skb; |
| } |
| |
| static struct sk_buff *ksz8795_rcv(struct sk_buff *skb, struct net_device *dev) |
| { |
| u8 *tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN; |
| |
| return ksz_common_rcv(skb, dev, tag[0] & 7, KSZ_EGRESS_TAG_LEN); |
| } |
| |
| static const struct dsa_device_ops ksz8795_netdev_ops = { |
| .name = "ksz8795", |
| .proto = DSA_TAG_PROTO_KSZ8795, |
| .xmit = ksz8795_xmit, |
| .rcv = ksz8795_rcv, |
| .needed_tailroom = KSZ_INGRESS_TAG_LEN, |
| }; |
| |
| DSA_TAG_DRIVER(ksz8795_netdev_ops); |
| MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8795); |
| |
| /* |
| * For Ingress (Host -> KSZ9477), 2 bytes are added before FCS. |
| * --------------------------------------------------------------------------- |
| * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|tag1(1byte)|FCS(4bytes) |
| * --------------------------------------------------------------------------- |
| * tag0 : Prioritization (not used now) |
| * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5) |
| * |
| * For Egress (KSZ9477 -> Host), 1 byte is added before FCS. |
| * --------------------------------------------------------------------------- |
| * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes) |
| * --------------------------------------------------------------------------- |
| * tag0 : zero-based value represents port |
| * (eg, 0x00=port1, 0x02=port3, 0x06=port7) |
| */ |
| |
| #define KSZ9477_INGRESS_TAG_LEN 2 |
| #define KSZ9477_PTP_TAG_LEN 4 |
| #define KSZ9477_PTP_TAG_INDICATION 0x80 |
| |
| #define KSZ9477_TAIL_TAG_OVERRIDE BIT(9) |
| #define KSZ9477_TAIL_TAG_LOOKUP BIT(10) |
| |
| static struct sk_buff *ksz9477_xmit(struct sk_buff *skb, |
| struct net_device *dev) |
| { |
| struct dsa_port *dp = dsa_slave_to_port(dev); |
| __be16 *tag; |
| u8 *addr; |
| u16 val; |
| |
| if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb)) |
| return NULL; |
| |
| /* Tag encoding */ |
| tag = skb_put(skb, KSZ9477_INGRESS_TAG_LEN); |
| addr = skb_mac_header(skb); |
| |
| val = BIT(dp->index); |
| |
| if (is_link_local_ether_addr(addr)) |
| val |= KSZ9477_TAIL_TAG_OVERRIDE; |
| |
| *tag = cpu_to_be16(val); |
| |
| return skb; |
| } |
| |
| static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev) |
| { |
| /* Tag decoding */ |
| u8 *tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN; |
| unsigned int port = tag[0] & 7; |
| unsigned int len = KSZ_EGRESS_TAG_LEN; |
| |
| /* Extra 4-bytes PTP timestamp */ |
| if (tag[0] & KSZ9477_PTP_TAG_INDICATION) |
| len += KSZ9477_PTP_TAG_LEN; |
| |
| return ksz_common_rcv(skb, dev, port, len); |
| } |
| |
| static const struct dsa_device_ops ksz9477_netdev_ops = { |
| .name = "ksz9477", |
| .proto = DSA_TAG_PROTO_KSZ9477, |
| .xmit = ksz9477_xmit, |
| .rcv = ksz9477_rcv, |
| .needed_tailroom = KSZ9477_INGRESS_TAG_LEN, |
| }; |
| |
| DSA_TAG_DRIVER(ksz9477_netdev_ops); |
| MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9477); |
| |
| #define KSZ9893_TAIL_TAG_OVERRIDE BIT(5) |
| #define KSZ9893_TAIL_TAG_LOOKUP BIT(6) |
| |
| static struct sk_buff *ksz9893_xmit(struct sk_buff *skb, |
| struct net_device *dev) |
| { |
| struct dsa_port *dp = dsa_slave_to_port(dev); |
| u8 *addr; |
| u8 *tag; |
| |
| if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb)) |
| return NULL; |
| |
| /* Tag encoding */ |
| tag = skb_put(skb, KSZ_INGRESS_TAG_LEN); |
| addr = skb_mac_header(skb); |
| |
| *tag = BIT(dp->index); |
| |
| if (is_link_local_ether_addr(addr)) |
| *tag |= KSZ9893_TAIL_TAG_OVERRIDE; |
| |
| return skb; |
| } |
| |
| static const struct dsa_device_ops ksz9893_netdev_ops = { |
| .name = "ksz9893", |
| .proto = DSA_TAG_PROTO_KSZ9893, |
| .xmit = ksz9893_xmit, |
| .rcv = ksz9477_rcv, |
| .needed_tailroom = KSZ_INGRESS_TAG_LEN, |
| }; |
| |
| DSA_TAG_DRIVER(ksz9893_netdev_ops); |
| MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893); |
| |
| static struct dsa_tag_driver *dsa_tag_driver_array[] = { |
| &DSA_TAG_DRIVER_NAME(ksz8795_netdev_ops), |
| &DSA_TAG_DRIVER_NAME(ksz9477_netdev_ops), |
| &DSA_TAG_DRIVER_NAME(ksz9893_netdev_ops), |
| }; |
| |
| module_dsa_tag_drivers(dsa_tag_driver_array); |
| |
| MODULE_LICENSE("GPL"); |