1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright 2019 NXP
3  */
4 #include <linux/dsa/ocelot.h>
5 
6 #include "tag.h"
7 
8 #define OCELOT_NAME	"ocelot"
9 #define SEVILLE_NAME	"seville"
10 
ocelot_xmit_common(struct sk_buff * skb,struct net_device * netdev,__be32 ifh_prefix,void ** ifh)11 static void ocelot_xmit_common(struct sk_buff *skb, struct net_device *netdev,
12 			       __be32 ifh_prefix, void **ifh)
13 {
14 	struct dsa_port *dp = dsa_user_to_port(netdev);
15 	struct dsa_switch *ds = dp->ds;
16 	u64 vlan_tci, tag_type;
17 	void *injection;
18 	__be32 *prefix;
19 	u32 rew_op = 0;
20 	u64 qos_class;
21 
22 	ocelot_xmit_get_vlan_info(skb, dsa_port_bridge_dev_get(dp), &vlan_tci,
23 				  &tag_type);
24 
25 	qos_class = netdev_get_num_tc(netdev) ?
26 		    netdev_get_prio_tc_map(netdev, skb->priority) : skb->priority;
27 
28 	injection = skb_push(skb, OCELOT_TAG_LEN);
29 	prefix = skb_push(skb, OCELOT_SHORT_PREFIX_LEN);
30 
31 	*prefix = ifh_prefix;
32 	memset(injection, 0, OCELOT_TAG_LEN);
33 	ocelot_ifh_set_bypass(injection, 1);
34 	ocelot_ifh_set_src(injection, ds->num_ports);
35 	ocelot_ifh_set_qos_class(injection, qos_class);
36 	ocelot_ifh_set_vlan_tci(injection, vlan_tci);
37 	ocelot_ifh_set_tag_type(injection, tag_type);
38 
39 	rew_op = ocelot_ptp_rew_op(skb);
40 	if (rew_op)
41 		ocelot_ifh_set_rew_op(injection, rew_op);
42 
43 	*ifh = injection;
44 }
45 
ocelot_xmit(struct sk_buff * skb,struct net_device * netdev)46 static struct sk_buff *ocelot_xmit(struct sk_buff *skb,
47 				   struct net_device *netdev)
48 {
49 	struct dsa_port *dp = dsa_user_to_port(netdev);
50 	void *injection;
51 
52 	ocelot_xmit_common(skb, netdev, cpu_to_be32(0x8880000a), &injection);
53 	ocelot_ifh_set_dest(injection, BIT_ULL(dp->index));
54 
55 	return skb;
56 }
57 
seville_xmit(struct sk_buff * skb,struct net_device * netdev)58 static struct sk_buff *seville_xmit(struct sk_buff *skb,
59 				    struct net_device *netdev)
60 {
61 	struct dsa_port *dp = dsa_user_to_port(netdev);
62 	void *injection;
63 
64 	ocelot_xmit_common(skb, netdev, cpu_to_be32(0x88800005), &injection);
65 	seville_ifh_set_dest(injection, BIT_ULL(dp->index));
66 
67 	return skb;
68 }
69 
ocelot_rcv(struct sk_buff * skb,struct net_device * netdev)70 static struct sk_buff *ocelot_rcv(struct sk_buff *skb,
71 				  struct net_device *netdev)
72 {
73 	u64 src_port, qos_class;
74 	u64 vlan_tci, tag_type;
75 	u8 *start = skb->data;
76 	struct dsa_port *dp;
77 	u8 *extraction;
78 	u16 vlan_tpid;
79 	u64 rew_val;
80 
81 	/* Revert skb->data by the amount consumed by the DSA conduit,
82 	 * so it points to the beginning of the frame.
83 	 */
84 	skb_push(skb, ETH_HLEN);
85 	/* We don't care about the short prefix, it is just for easy entrance
86 	 * into the DSA conduit's RX filter. Discard it now by moving it into
87 	 * the headroom.
88 	 */
89 	skb_pull(skb, OCELOT_SHORT_PREFIX_LEN);
90 	/* And skb->data now points to the extraction frame header.
91 	 * Keep a pointer to it.
92 	 */
93 	extraction = skb->data;
94 	/* Now the EFH is part of the headroom as well */
95 	skb_pull(skb, OCELOT_TAG_LEN);
96 	/* Reset the pointer to the real MAC header */
97 	skb_reset_mac_header(skb);
98 	skb_reset_mac_len(skb);
99 	/* And move skb->data to the correct location again */
100 	skb_pull(skb, ETH_HLEN);
101 
102 	/* Remove from inet csum the extraction header */
103 	skb_postpull_rcsum(skb, start, OCELOT_TOTAL_TAG_LEN);
104 
105 	ocelot_xfh_get_src_port(extraction, &src_port);
106 	ocelot_xfh_get_qos_class(extraction, &qos_class);
107 	ocelot_xfh_get_tag_type(extraction, &tag_type);
108 	ocelot_xfh_get_vlan_tci(extraction, &vlan_tci);
109 	ocelot_xfh_get_rew_val(extraction, &rew_val);
110 
111 	skb->dev = dsa_conduit_find_user(netdev, 0, src_port);
112 	if (!skb->dev)
113 		/* The switch will reflect back some frames sent through
114 		 * sockets opened on the bare DSA conduit. These will come back
115 		 * with src_port equal to the index of the CPU port, for which
116 		 * there is no user registered. So don't print any error
117 		 * message here (ignore and drop those frames).
118 		 */
119 		return NULL;
120 
121 	dsa_default_offload_fwd_mark(skb);
122 	skb->priority = qos_class;
123 	OCELOT_SKB_CB(skb)->tstamp_lo = rew_val;
124 
125 	/* Ocelot switches copy frames unmodified to the CPU. However, it is
126 	 * possible for the user to request a VLAN modification through
127 	 * VCAP_IS1_ACT_VID_REPLACE_ENA. In this case, what will happen is that
128 	 * the VLAN ID field from the Extraction Header gets updated, but the
129 	 * 802.1Q header does not (the classified VLAN only becomes visible on
130 	 * egress through the "port tag" of front-panel ports).
131 	 * So, for traffic extracted by the CPU, we want to pick up the
132 	 * classified VLAN and manually replace the existing 802.1Q header from
133 	 * the packet with it, so that the operating system is always up to
134 	 * date with the result of tc-vlan actions.
135 	 * NOTE: In VLAN-unaware mode, we don't want to do that, we want the
136 	 * frame to remain unmodified, because the classified VLAN is always
137 	 * equal to the pvid of the ingress port and should not be used for
138 	 * processing.
139 	 */
140 	dp = dsa_user_to_port(skb->dev);
141 	vlan_tpid = tag_type ? ETH_P_8021AD : ETH_P_8021Q;
142 
143 	if (dsa_port_is_vlan_filtering(dp) &&
144 	    eth_hdr(skb)->h_proto == htons(vlan_tpid)) {
145 		u16 dummy_vlan_tci;
146 
147 		skb_push_rcsum(skb, ETH_HLEN);
148 		__skb_vlan_pop(skb, &dummy_vlan_tci);
149 		skb_pull_rcsum(skb, ETH_HLEN);
150 		__vlan_hwaccel_put_tag(skb, htons(vlan_tpid), vlan_tci);
151 	}
152 
153 	return skb;
154 }
155 
156 static const struct dsa_device_ops ocelot_netdev_ops = {
157 	.name			= OCELOT_NAME,
158 	.proto			= DSA_TAG_PROTO_OCELOT,
159 	.xmit			= ocelot_xmit,
160 	.rcv			= ocelot_rcv,
161 	.needed_headroom	= OCELOT_TOTAL_TAG_LEN,
162 	.promisc_on_conduit	= true,
163 };
164 
165 DSA_TAG_DRIVER(ocelot_netdev_ops);
166 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT, OCELOT_NAME);
167 
168 static const struct dsa_device_ops seville_netdev_ops = {
169 	.name			= SEVILLE_NAME,
170 	.proto			= DSA_TAG_PROTO_SEVILLE,
171 	.xmit			= seville_xmit,
172 	.rcv			= ocelot_rcv,
173 	.needed_headroom	= OCELOT_TOTAL_TAG_LEN,
174 	.promisc_on_conduit	= true,
175 };
176 
177 DSA_TAG_DRIVER(seville_netdev_ops);
178 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SEVILLE, SEVILLE_NAME);
179 
180 static struct dsa_tag_driver *ocelot_tag_driver_array[] = {
181 	&DSA_TAG_DRIVER_NAME(ocelot_netdev_ops),
182 	&DSA_TAG_DRIVER_NAME(seville_netdev_ops),
183 };
184 
185 module_dsa_tag_drivers(ocelot_tag_driver_array);
186 
187 MODULE_DESCRIPTION("DSA tag driver for Ocelot family of switches, using NPI port");
188 MODULE_LICENSE("GPL v2");
189