From cafdc45c949b9963cbfb8fe3a68d0ab16b0208ce Mon Sep 17 00:00:00 2001 From: John Crispin Date: Thu, 15 Sep 2016 16:26:40 +0200 Subject: [PATCH] net-next: dsa: add Qualcomm tag RX/TX handler Add support for the 2-bytes Qualcomm tag that gigabit switches such as the QCA8337/N might insert when receiving packets, or that we need to insert while targeting specific switch ports. The tag is inserted directly behind the ethernet header. Reviewed-by: Andrew Lunn Reviewed-by: Florian Fainelli Signed-off-by: John Crispin Signed-off-by: David S. Miller --- include/net/dsa.h | 1 + net/dsa/Kconfig | 3 + net/dsa/Makefile | 1 + net/dsa/dsa.c | 3 + net/dsa/dsa_priv.h | 2 + net/dsa/tag_qca.c | 138 +++++++++++++++++++++++++++++++++++++++++++++ 6 files changed, 148 insertions(+) create mode 100644 net/dsa/tag_qca.c diff --git a/include/net/dsa.h b/include/net/dsa.h index 9d97c5214341..7556646db2d3 100644 --- a/include/net/dsa.h +++ b/include/net/dsa.h @@ -26,6 +26,7 @@ enum dsa_tag_protocol { DSA_TAG_PROTO_TRAILER, DSA_TAG_PROTO_EDSA, DSA_TAG_PROTO_BRCM, + DSA_TAG_PROTO_QCA, DSA_TAG_LAST, /* MUST BE LAST */ }; diff --git a/net/dsa/Kconfig b/net/dsa/Kconfig index ff7736f7ff42..96e47c539bee 100644 --- a/net/dsa/Kconfig +++ b/net/dsa/Kconfig @@ -38,4 +38,7 @@ config NET_DSA_TAG_EDSA config NET_DSA_TAG_TRAILER bool +config NET_DSA_TAG_QCA + bool + endif diff --git a/net/dsa/Makefile b/net/dsa/Makefile index 8af4ded70f1c..a3380ed0e0be 100644 --- a/net/dsa/Makefile +++ b/net/dsa/Makefile @@ -7,3 +7,4 @@ dsa_core-$(CONFIG_NET_DSA_TAG_BRCM) += tag_brcm.o dsa_core-$(CONFIG_NET_DSA_TAG_DSA) += tag_dsa.o dsa_core-$(CONFIG_NET_DSA_TAG_EDSA) += tag_edsa.o dsa_core-$(CONFIG_NET_DSA_TAG_TRAILER) += tag_trailer.o +dsa_core-$(CONFIG_NET_DSA_TAG_QCA) += tag_qca.o diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c index d8d267e9a872..66e31acfcad8 100644 --- a/net/dsa/dsa.c +++ b/net/dsa/dsa.c @@ -53,6 +53,9 @@ const struct dsa_device_ops *dsa_device_ops[DSA_TAG_LAST] = { #endif #ifdef CONFIG_NET_DSA_TAG_BRCM [DSA_TAG_PROTO_BRCM] = &brcm_netdev_ops, +#endif +#ifdef CONFIG_NET_DSA_TAG_QCA + [DSA_TAG_PROTO_QCA] = &qca_netdev_ops, #endif [DSA_TAG_PROTO_NONE] = &none_ops, }; diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h index 00077a9c97f4..6cfd7388834e 100644 --- a/net/dsa/dsa_priv.h +++ b/net/dsa/dsa_priv.h @@ -81,5 +81,7 @@ extern const struct dsa_device_ops trailer_netdev_ops; /* tag_brcm.c */ extern const struct dsa_device_ops brcm_netdev_ops; +/* tag_qca.c */ +extern const struct dsa_device_ops qca_netdev_ops; #endif diff --git a/net/dsa/tag_qca.c b/net/dsa/tag_qca.c new file mode 100644 index 000000000000..0c90cacee7aa --- /dev/null +++ b/net/dsa/tag_qca.c @@ -0,0 +1,138 @@ +/* + * 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 +#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) + goto out_free; + + 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->port); + + *phdr = htons(hdr); + + return skb; + +out_free: + kfree_skb(skb); + return NULL; +} + +static int qca_tag_rcv(struct sk_buff *skb, struct net_device *dev, + struct packet_type *pt, struct net_device *orig_dev) +{ + struct dsa_switch_tree *dst = dev->dsa_ptr; + struct dsa_switch *ds; + u8 ver; + int port; + __be16 *phdr, hdr; + + if (unlikely(!dst)) + goto out_drop; + + skb = skb_unshare(skb, GFP_ATOMIC); + if (!skb) + goto out; + + if (unlikely(!pskb_may_pull(skb, QCA_HDR_LEN))) + goto out_drop; + + /* 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)) + goto out_drop; + + /* 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 = dst->ds[0]; + if (!ds) + goto out_drop; + + /* Get source port information */ + port = (hdr & QCA_HDR_RECV_SOURCE_PORT_MASK); + if (!ds->ports[port].netdev) + goto out_drop; + + /* Update skb & forward the frame accordingly */ + skb_push(skb, ETH_HLEN); + skb->pkt_type = PACKET_HOST; + skb->dev = ds->ports[port].netdev; + skb->protocol = eth_type_trans(skb, skb->dev); + + skb->dev->stats.rx_packets++; + skb->dev->stats.rx_bytes += skb->len; + + netif_receive_skb(skb); + + return 0; + +out_drop: + kfree_skb(skb); +out: + return 0; +} + +const struct dsa_device_ops qca_netdev_ops = { + .xmit = qca_tag_xmit, + .rcv = qca_tag_rcv, +}; -- 2.20.1