| /* |
| * Copyright (c) 2015, The Linux Foundation. All rights reserved. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 and |
| * only version 2 as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| */ |
| |
| #include <linux/etherdevice.h> |
| |
| #include "dsa_priv.h" |
| |
| #define QCA_HDR_LEN 2 |
| #define QCA_HDR_VERSION 0x2 |
| |
| #define QCA_HDR_RECV_VERSION_MASK GENMASK(15, 14) |
| #define QCA_HDR_RECV_VERSION_S 14 |
| #define QCA_HDR_RECV_PRIORITY_MASK GENMASK(13, 11) |
| #define QCA_HDR_RECV_PRIORITY_S 11 |
| #define QCA_HDR_RECV_TYPE_MASK GENMASK(10, 6) |
| #define QCA_HDR_RECV_TYPE_S 6 |
| #define QCA_HDR_RECV_FRAME_IS_TAGGED BIT(3) |
| #define QCA_HDR_RECV_SOURCE_PORT_MASK GENMASK(2, 0) |
| |
| #define QCA_HDR_XMIT_VERSION_MASK GENMASK(15, 14) |
| #define QCA_HDR_XMIT_VERSION_S 14 |
| #define QCA_HDR_XMIT_PRIORITY_MASK GENMASK(13, 11) |
| #define QCA_HDR_XMIT_PRIORITY_S 11 |
| #define QCA_HDR_XMIT_CONTROL_MASK GENMASK(10, 8) |
| #define QCA_HDR_XMIT_CONTROL_S 8 |
| #define QCA_HDR_XMIT_FROM_CPU BIT(7) |
| #define QCA_HDR_XMIT_DP_BIT_MASK GENMASK(6, 0) |
| |
| static struct sk_buff *qca_tag_xmit(struct sk_buff *skb, struct net_device *dev) |
| { |
| struct dsa_slave_priv *p = netdev_priv(dev); |
| u16 *phdr, hdr; |
| |
| dev->stats.tx_packets++; |
| dev->stats.tx_bytes += skb->len; |
| |
| if (skb_cow_head(skb, 0) < 0) |
| return NULL; |
| |
| skb_push(skb, QCA_HDR_LEN); |
| |
| memmove(skb->data, skb->data + QCA_HDR_LEN, 2 * ETH_ALEN); |
| phdr = (u16 *)(skb->data + 2 * ETH_ALEN); |
| |
| /* Set the version field, and set destination port information */ |
| hdr = QCA_HDR_VERSION << QCA_HDR_XMIT_VERSION_S | |
| QCA_HDR_XMIT_FROM_CPU | |
| BIT(p->dp->index); |
| |
| *phdr = htons(hdr); |
| |
| return skb; |
| } |
| |
| static struct sk_buff *qca_tag_rcv(struct sk_buff *skb, struct net_device *dev, |
| struct packet_type *pt) |
| { |
| struct dsa_switch_tree *dst = dev->dsa_ptr; |
| struct dsa_port *cpu_dp = dsa_get_cpu_port(dst); |
| struct dsa_switch *ds; |
| u8 ver; |
| int port; |
| __be16 *phdr, hdr; |
| |
| if (unlikely(!pskb_may_pull(skb, QCA_HDR_LEN))) |
| return NULL; |
| |
| /* The QCA header is added by the switch between src addr and Ethertype |
| * At this point, skb->data points to ethertype so header should be |
| * right before |
| */ |
| phdr = (__be16 *)(skb->data - 2); |
| hdr = ntohs(*phdr); |
| |
| /* Make sure the version is correct */ |
| ver = (hdr & QCA_HDR_RECV_VERSION_MASK) >> QCA_HDR_RECV_VERSION_S; |
| if (unlikely(ver != QCA_HDR_VERSION)) |
| return NULL; |
| |
| /* Remove QCA tag and recalculate checksum */ |
| skb_pull_rcsum(skb, QCA_HDR_LEN); |
| memmove(skb->data - ETH_HLEN, skb->data - ETH_HLEN - QCA_HDR_LEN, |
| ETH_HLEN - QCA_HDR_LEN); |
| |
| /* This protocol doesn't support cascading multiple switches so it's |
| * safe to assume the switch is first in the tree |
| */ |
| ds = cpu_dp->ds; |
| if (!ds) |
| return NULL; |
| |
| /* Get source port information */ |
| port = (hdr & QCA_HDR_RECV_SOURCE_PORT_MASK); |
| if (!ds->ports[port].netdev) |
| return NULL; |
| |
| /* Update skb & forward the frame accordingly */ |
| skb->dev = ds->ports[port].netdev; |
| |
| return skb; |
| } |
| |
| const struct dsa_device_ops qca_netdev_ops = { |
| .xmit = qca_tag_xmit, |
| .rcv = qca_tag_rcv, |
| }; |