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 dsa_alloc_etype_header(skb, QCA_HDR_LEN); 40 phdr = dsa_etype_header_pos_tx(skb); 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 { 53 u8 ver; 54 u16 hdr; 55 int port; 56 __be16 *phdr; 57 58 if (unlikely(!pskb_may_pull(skb, QCA_HDR_LEN))) 59 return NULL; 60 61 phdr = dsa_etype_header_pos_rx(skb); 62 hdr = ntohs(*phdr); 63 64 /* Make sure the version is correct */ 65 ver = (hdr & QCA_HDR_RECV_VERSION_MASK) >> QCA_HDR_RECV_VERSION_S; 66 if (unlikely(ver != QCA_HDR_VERSION)) 67 return NULL; 68 69 /* Remove QCA tag and recalculate checksum */ 70 skb_pull_rcsum(skb, QCA_HDR_LEN); 71 dsa_strip_etype_header(skb, QCA_HDR_LEN); 72 73 /* Get source port information */ 74 port = (hdr & QCA_HDR_RECV_SOURCE_PORT_MASK); 75 76 skb->dev = dsa_master_find_slave(dev, 0, port); 77 if (!skb->dev) 78 return NULL; 79 80 return skb; 81 } 82 83 static const struct dsa_device_ops qca_netdev_ops = { 84 .name = "qca", 85 .proto = DSA_TAG_PROTO_QCA, 86 .xmit = qca_tag_xmit, 87 .rcv = qca_tag_rcv, 88 .needed_headroom = QCA_HDR_LEN, 89 }; 90 91 MODULE_LICENSE("GPL"); 92 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_QCA); 93 94 module_dsa_tag_driver(qca_netdev_ops); 95