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#define HSR_SUP_SEQNR_START		(HSR_SEQNR_START / 2)
 34
 35
 36/* How often shall we check for broken ring and remove node entries older than
 37 * HSR_NODE_FORGET_TIME?
 38 */
 39#define PRUNE_PERIOD			 3000 /* ms */
 40
 41
 42#define HSR_TLV_ANNOUNCE		   22
 43#define HSR_TLV_LIFE_CHECK		   23
 44
 45
 46/* HSR Tag.
 47 * As defined in IEC-62439-3:2010, the HSR tag is really { ethertype = 0x88FB,
 48 * path, LSDU_size, sequence Nr }. But we let eth_header() create { h_dest,
 49 * h_source, h_proto = 0x88FB }, and add { path, LSDU_size, sequence Nr,
 50 * encapsulated protocol } instead.
 51 *
 52 * Field names as defined in the IEC:2010 standard for HSR.
 53 */
 54struct hsr_tag {
 55	__be16		path_and_LSDU_size;
 56	__be16		sequence_nr;
 57	__be16		encap_proto;
 58} __packed;
 59
 60#define HSR_HLEN	6
 61
 62#define HSR_V1_SUP_LSDUSIZE		52
 63
 64/* The helper functions below assumes that 'path' occupies the 4 most
 65 * significant bits of the 16-bit field shared by 'path' and 'LSDU_size' (or
 66 * equivalently, the 4 most significant bits of HSR tag byte 14).
 67 *
 68 * This is unclear in the IEC specification; its definition of MAC addresses
 69 * indicates the spec is written with the least significant bit first (to the
 70 * left). This, however, would mean that the LSDU field would be split in two
 71 * with the path field in-between, which seems strange. I'm guessing the MAC
 72 * address definition is in error.
 73 */
 74static inline u16 get_hsr_tag_path(struct hsr_tag *ht)
 75{
 76	return ntohs(ht->path_and_LSDU_size) >> 12;
 77}
 78
 79static inline u16 get_hsr_tag_LSDU_size(struct hsr_tag *ht)
 80{
 81	return ntohs(ht->path_and_LSDU_size) & 0x0FFF;
 82}
 83
 84static inline void set_hsr_tag_path(struct hsr_tag *ht, u16 path)
 85{
 86	ht->path_and_LSDU_size = htons(
 87			(ntohs(ht->path_and_LSDU_size) & 0x0FFF) | (path << 12));
 88}
 89
 90static inline void set_hsr_tag_LSDU_size(struct hsr_tag *ht, u16 LSDU_size)
 91{
 92	ht->path_and_LSDU_size = htons(
 93			(ntohs(ht->path_and_LSDU_size) & 0xF000) |
 94			(LSDU_size & 0x0FFF));
 95}
 96
 97struct hsr_ethhdr {
 98	struct ethhdr	ethhdr;
 99	struct hsr_tag	hsr_tag;
100} __packed;
101
102
103/* HSR Supervision Frame data types.
104 * Field names as defined in the IEC:2010 standard for HSR.
105 */
106struct hsr_sup_tag {
107	__be16		path_and_HSR_Ver;
108	__be16		sequence_nr;
109	__u8		HSR_TLV_Type;
110	__u8		HSR_TLV_Length;
111} __packed;
112
113struct hsr_sup_payload {
114	unsigned char	MacAddressA[ETH_ALEN];
115} __packed;
116
117static inline u16 get_hsr_stag_path(struct hsr_sup_tag *hst)
118{
119	return get_hsr_tag_path((struct hsr_tag *) hst);
120}
121
122static inline u16 get_hsr_stag_HSR_ver(struct hsr_sup_tag *hst)
123{
124	return get_hsr_tag_LSDU_size((struct hsr_tag *) hst);
125}
126
127static inline void set_hsr_stag_path(struct hsr_sup_tag *hst, u16 path)
128{
129	set_hsr_tag_path((struct hsr_tag *) hst, path);
130}
131
132static inline void set_hsr_stag_HSR_Ver(struct hsr_sup_tag *hst, u16 HSR_Ver)
133{
134	set_hsr_tag_LSDU_size((struct hsr_tag *) hst, HSR_Ver);
135}
136
137struct hsrv0_ethhdr_sp {
138	struct ethhdr		ethhdr;
139	struct hsr_sup_tag	hsr_sup;
140} __packed;
141
142struct hsrv1_ethhdr_sp {
143	struct ethhdr		ethhdr;
144	struct hsr_tag		hsr;
145	struct hsr_sup_tag	hsr_sup;
146} __packed;
147
148
149enum hsr_port_type {
150	HSR_PT_NONE = 0,	/* Must be 0, used by framereg */
151	HSR_PT_SLAVE_A,
152	HSR_PT_SLAVE_B,
153	HSR_PT_INTERLINK,
154	HSR_PT_MASTER,
155	HSR_PT_PORTS,	/* This must be the last item in the enum */
156};
157
158struct hsr_port {
159	struct list_head	port_list;
160	struct net_device	*dev;
161	struct hsr_priv		*hsr;
162	enum hsr_port_type	type;
163};
164
165struct hsr_priv {
166	struct rcu_head		rcu_head;
167	struct list_head	ports;
168	struct list_head	node_db;	/* Known HSR nodes */
169	struct list_head	self_node_db;	/* MACs of slaves */
170	struct timer_list	announce_timer;	/* Supervision frame dispatch */
171	struct timer_list	prune_timer;
172	int announce_count;
173	u16 sequence_nr;
174	u16 sup_sequence_nr;			/* For HSRv1 separate seq_nr for supervision */
175	u8 protVersion;					/* Indicate if HSRv0 or HSRv1. */
176	spinlock_t seqnr_lock;			/* locking for sequence_nr */
177	unsigned char		sup_multicast_addr[ETH_ALEN];
178};
179
180#define hsr_for_each_port(hsr, port) \
181	list_for_each_entry_rcu((port), &(hsr)->ports, port_list)
182
183struct hsr_port *hsr_port_get_hsr(struct hsr_priv *hsr, enum hsr_port_type pt);
184
185/* Caller must ensure skb is a valid HSR frame */
186static inline u16 hsr_get_skb_sequence_nr(struct sk_buff *skb)
187{
188	struct hsr_ethhdr *hsr_ethhdr;
189
190	hsr_ethhdr = (struct hsr_ethhdr *) skb_mac_header(skb);
191	return ntohs(hsr_ethhdr->hsr_tag.sequence_nr);
192}
193
194#endif /*  __HSR_PRIVATE_H */