xref: /openbmc/linux/net/hsr/hsr_main.h (revision 2572f00d)
1 /* Copyright 2011-2014 Autronica Fire and Security AS
2  *
3  * This program is free software; you can redistribute it and/or modify it
4  * under the terms of the GNU General Public License as published by the Free
5  * Software Foundation; either version 2 of the License, or (at your option)
6  * any later version.
7  *
8  * Author(s):
9  *	2011-2014 Arvid Brodin, arvid.brodin@alten.se
10  */
11 
12 #ifndef __HSR_PRIVATE_H
13 #define __HSR_PRIVATE_H
14 
15 #include <linux/netdevice.h>
16 #include <linux/list.h>
17 
18 
19 /* Time constants as specified in the HSR specification (IEC-62439-3 2010)
20  * Table 8.
21  * All values in milliseconds.
22  */
23 #define HSR_LIFE_CHECK_INTERVAL		 2000 /* ms */
24 #define HSR_NODE_FORGET_TIME		60000 /* ms */
25 #define HSR_ANNOUNCE_INTERVAL		  100 /* ms */
26 
27 
28 /* By how much may slave1 and slave2 timestamps of latest received frame from
29  * each node differ before we notify of communication problem?
30  */
31 #define MAX_SLAVE_DIFF			 3000 /* ms */
32 #define HSR_SEQNR_START			(USHRT_MAX - 1024)
33 
34 
35 /* How often shall we check for broken ring and remove node entries older than
36  * HSR_NODE_FORGET_TIME?
37  */
38 #define PRUNE_PERIOD			 3000 /* ms */
39 
40 
41 #define HSR_TLV_ANNOUNCE		   22
42 #define HSR_TLV_LIFE_CHECK		   23
43 
44 
45 /* HSR Tag.
46  * As defined in IEC-62439-3:2010, the HSR tag is really { ethertype = 0x88FB,
47  * path, LSDU_size, sequence Nr }. But we let eth_header() create { h_dest,
48  * h_source, h_proto = 0x88FB }, and add { path, LSDU_size, sequence Nr,
49  * encapsulated protocol } instead.
50  *
51  * Field names as defined in the IEC:2010 standard for HSR.
52  */
53 struct hsr_tag {
54 	__be16		path_and_LSDU_size;
55 	__be16		sequence_nr;
56 	__be16		encap_proto;
57 } __packed;
58 
59 #define HSR_HLEN	6
60 
61 /* The helper functions below assumes that 'path' occupies the 4 most
62  * significant bits of the 16-bit field shared by 'path' and 'LSDU_size' (or
63  * equivalently, the 4 most significant bits of HSR tag byte 14).
64  *
65  * This is unclear in the IEC specification; its definition of MAC addresses
66  * indicates the spec is written with the least significant bit first (to the
67  * left). This, however, would mean that the LSDU field would be split in two
68  * with the path field in-between, which seems strange. I'm guessing the MAC
69  * address definition is in error.
70  */
71 static inline u16 get_hsr_tag_path(struct hsr_tag *ht)
72 {
73 	return ntohs(ht->path_and_LSDU_size) >> 12;
74 }
75 
76 static inline u16 get_hsr_tag_LSDU_size(struct hsr_tag *ht)
77 {
78 	return ntohs(ht->path_and_LSDU_size) & 0x0FFF;
79 }
80 
81 static inline void set_hsr_tag_path(struct hsr_tag *ht, u16 path)
82 {
83 	ht->path_and_LSDU_size = htons(
84 			(ntohs(ht->path_and_LSDU_size) & 0x0FFF) | (path << 12));
85 }
86 
87 static inline void set_hsr_tag_LSDU_size(struct hsr_tag *ht, u16 LSDU_size)
88 {
89 	ht->path_and_LSDU_size = htons(
90 			(ntohs(ht->path_and_LSDU_size) & 0xF000) |
91 			(LSDU_size & 0x0FFF));
92 }
93 
94 struct hsr_ethhdr {
95 	struct ethhdr	ethhdr;
96 	struct hsr_tag	hsr_tag;
97 } __packed;
98 
99 
100 /* HSR Supervision Frame data types.
101  * Field names as defined in the IEC:2010 standard for HSR.
102  */
103 struct hsr_sup_tag {
104 	__be16		path_and_HSR_Ver;
105 	__be16		sequence_nr;
106 	__u8		HSR_TLV_Type;
107 	__u8		HSR_TLV_Length;
108 } __packed;
109 
110 struct hsr_sup_payload {
111 	unsigned char	MacAddressA[ETH_ALEN];
112 } __packed;
113 
114 static inline u16 get_hsr_stag_path(struct hsr_sup_tag *hst)
115 {
116 	return get_hsr_tag_path((struct hsr_tag *) hst);
117 }
118 
119 static inline u16 get_hsr_stag_HSR_ver(struct hsr_sup_tag *hst)
120 {
121 	return get_hsr_tag_LSDU_size((struct hsr_tag *) hst);
122 }
123 
124 static inline void set_hsr_stag_path(struct hsr_sup_tag *hst, u16 path)
125 {
126 	set_hsr_tag_path((struct hsr_tag *) hst, path);
127 }
128 
129 static inline void set_hsr_stag_HSR_Ver(struct hsr_sup_tag *hst, u16 HSR_Ver)
130 {
131 	set_hsr_tag_LSDU_size((struct hsr_tag *) hst, HSR_Ver);
132 }
133 
134 struct hsr_ethhdr_sp {
135 	struct ethhdr		ethhdr;
136 	struct hsr_sup_tag	hsr_sup;
137 } __packed;
138 
139 
140 enum hsr_port_type {
141 	HSR_PT_NONE = 0,	/* Must be 0, used by framereg */
142 	HSR_PT_SLAVE_A,
143 	HSR_PT_SLAVE_B,
144 	HSR_PT_INTERLINK,
145 	HSR_PT_MASTER,
146 	HSR_PT_PORTS,	/* This must be the last item in the enum */
147 };
148 
149 struct hsr_port {
150 	struct list_head	port_list;
151 	struct net_device	*dev;
152 	struct hsr_priv		*hsr;
153 	enum hsr_port_type	type;
154 };
155 
156 struct hsr_priv {
157 	struct rcu_head		rcu_head;
158 	struct list_head	ports;
159 	struct list_head	node_db;	/* Known HSR nodes */
160 	struct list_head	self_node_db;	/* MACs of slaves */
161 	struct timer_list	announce_timer;	/* Supervision frame dispatch */
162 	struct timer_list	prune_timer;
163 	int announce_count;
164 	u16 sequence_nr;
165 	spinlock_t seqnr_lock;			/* locking for sequence_nr */
166 	unsigned char		sup_multicast_addr[ETH_ALEN];
167 };
168 
169 #define hsr_for_each_port(hsr, port) \
170 	list_for_each_entry_rcu((port), &(hsr)->ports, port_list)
171 
172 struct hsr_port *hsr_port_get_hsr(struct hsr_priv *hsr, enum hsr_port_type pt);
173 
174 /* Caller must ensure skb is a valid HSR frame */
175 static inline u16 hsr_get_skb_sequence_nr(struct sk_buff *skb)
176 {
177 	struct hsr_ethhdr *hsr_ethhdr;
178 
179 	hsr_ethhdr = (struct hsr_ethhdr *) skb_mac_header(skb);
180 	return ntohs(hsr_ethhdr->hsr_tag.sequence_nr);
181 }
182 
183 #endif /*  __HSR_PRIVATE_H */
184