1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2015, The Linux Foundation. All rights reserved. 4 */ 5 6 #include <linux/etherdevice.h> 7 8 #include "dsa_priv.h" 9 10 #define QCA_HDR_LEN 2 11 #define QCA_HDR_VERSION 0x2 12 13 #define QCA_HDR_RECV_VERSION_MASK GENMASK(15, 14) 14 #define QCA_HDR_RECV_VERSION_S 14 15 #define QCA_HDR_RECV_PRIORITY_MASK GENMASK(13, 11) 16 #define QCA_HDR_RECV_PRIORITY_S 11 17 #define QCA_HDR_RECV_TYPE_MASK GENMASK(10, 6) 18 #define QCA_HDR_RECV_TYPE_S 6 19 #define QCA_HDR_RECV_FRAME_IS_TAGGED BIT(3) 20 #define QCA_HDR_RECV_SOURCE_PORT_MASK GENMASK(2, 0) 21 22 #define QCA_HDR_XMIT_VERSION_MASK GENMASK(15, 14) 23 #define QCA_HDR_XMIT_VERSION_S 14 24 #define QCA_HDR_XMIT_PRIORITY_MASK GENMASK(13, 11) 25 #define QCA_HDR_XMIT_PRIORITY_S 11 26 #define QCA_HDR_XMIT_CONTROL_MASK GENMASK(10, 8) 27 #define QCA_HDR_XMIT_CONTROL_S 8 28 #define QCA_HDR_XMIT_FROM_CPU BIT(7) 29 #define QCA_HDR_XMIT_DP_BIT_MASK GENMASK(6, 0) 30 31 static struct sk_buff *qca_tag_xmit(struct sk_buff *skb, struct net_device *dev) 32 { 33 struct dsa_port *dp = dsa_slave_to_port(dev); 34 __be16 *phdr; 35 u16 hdr; 36 37 skb_push(skb, QCA_HDR_LEN); 38 39 memmove(skb->data, skb->data + QCA_HDR_LEN, 2 * ETH_ALEN); 40 phdr = (__be16 *)(skb->data + 2 * ETH_ALEN); 41 42 /* Set the version field, and set destination port information */ 43 hdr = QCA_HDR_VERSION << QCA_HDR_XMIT_VERSION_S | 44 QCA_HDR_XMIT_FROM_CPU | BIT(dp->index); 45 46 *phdr = htons(hdr); 47 48 return skb; 49 } 50 51 static struct sk_buff *qca_tag_rcv(struct sk_buff *skb, struct net_device *dev, 52 struct packet_type *pt) 53 { 54 u8 ver; 55 u16 hdr; 56 int port; 57 __be16 *phdr; 58 59 if (unlikely(!pskb_may_pull(skb, QCA_HDR_LEN))) 60 return NULL; 61 62 /* The QCA header is added by the switch between src addr and Ethertype 63 * At this point, skb->data points to ethertype so header should be 64 * right before 65 */ 66 phdr = (__be16 *)(skb->data - 2); 67 hdr = ntohs(*phdr); 68 69 /* Make sure the version is correct */ 70 ver = (hdr & QCA_HDR_RECV_VERSION_MASK) >> QCA_HDR_RECV_VERSION_S; 71 if (unlikely(ver != QCA_HDR_VERSION)) 72 return NULL; 73 74 /* Remove QCA tag and recalculate checksum */ 75 skb_pull_rcsum(skb, QCA_HDR_LEN); 76 memmove(skb->data - ETH_HLEN, skb->data - ETH_HLEN - QCA_HDR_LEN, 77 ETH_HLEN - QCA_HDR_LEN); 78 79 /* Get source port information */ 80 port = (hdr & QCA_HDR_RECV_SOURCE_PORT_MASK); 81 82 skb->dev = dsa_master_find_slave(dev, 0, port); 83 if (!skb->dev) 84 return NULL; 85 86 return skb; 87 } 88 89 static const struct dsa_device_ops qca_netdev_ops = { 90 .name = "qca", 91 .proto = DSA_TAG_PROTO_QCA, 92 .xmit = qca_tag_xmit, 93 .rcv = qca_tag_rcv, 94 .overhead = QCA_HDR_LEN, 95 }; 96 97 MODULE_LICENSE("GPL"); 98 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_QCA); 99 100 module_dsa_tag_driver(qca_netdev_ops); 101