1 /*
2  * drivers/net/ethernet/rocker/rocker_tlv.h - Rocker switch device driver
3  * Copyright (c) 2014-2016 Jiri Pirko <jiri@mellanox.com>
4  * Copyright (c) 2014 Scott Feldman <sfeldma@gmail.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  */
11 
12 #ifndef _ROCKER_TLV_H
13 #define _ROCKER_TLV_H
14 
15 #include <linux/types.h>
16 
17 #include "rocker_hw.h"
18 #include "rocker.h"
19 
20 #define ROCKER_TLV_ALIGNTO 8U
21 #define ROCKER_TLV_ALIGN(len) \
22 	(((len) + ROCKER_TLV_ALIGNTO - 1) & ~(ROCKER_TLV_ALIGNTO - 1))
23 #define ROCKER_TLV_HDRLEN ROCKER_TLV_ALIGN(sizeof(struct rocker_tlv))
24 
25 /*  <------- ROCKER_TLV_HDRLEN -------> <--- ROCKER_TLV_ALIGN(payload) --->
26  * +-----------------------------+- - -+- - - - - - - - - - - - - - -+- - -+
27  * |             Header          | Pad |           Payload           | Pad |
28  * |      (struct rocker_tlv)    | ing |                             | ing |
29  * +-----------------------------+- - -+- - - - - - - - - - - - - - -+- - -+
30  *  <--------------------------- tlv->len -------------------------->
31  */
32 
33 static inline struct rocker_tlv *rocker_tlv_next(const struct rocker_tlv *tlv,
34 						 int *remaining)
35 {
36 	int totlen = ROCKER_TLV_ALIGN(tlv->len);
37 
38 	*remaining -= totlen;
39 	return (struct rocker_tlv *) ((char *) tlv + totlen);
40 }
41 
42 static inline int rocker_tlv_ok(const struct rocker_tlv *tlv, int remaining)
43 {
44 	return remaining >= (int) ROCKER_TLV_HDRLEN &&
45 	       tlv->len >= ROCKER_TLV_HDRLEN &&
46 	       tlv->len <= remaining;
47 }
48 
49 #define rocker_tlv_for_each(pos, head, len, rem)	\
50 	for (pos = head, rem = len;			\
51 	     rocker_tlv_ok(pos, rem);			\
52 	     pos = rocker_tlv_next(pos, &(rem)))
53 
54 #define rocker_tlv_for_each_nested(pos, tlv, rem)	\
55 	rocker_tlv_for_each(pos, rocker_tlv_data(tlv),	\
56 			    rocker_tlv_len(tlv), rem)
57 
58 static inline int rocker_tlv_attr_size(int payload)
59 {
60 	return ROCKER_TLV_HDRLEN + payload;
61 }
62 
63 static inline int rocker_tlv_total_size(int payload)
64 {
65 	return ROCKER_TLV_ALIGN(rocker_tlv_attr_size(payload));
66 }
67 
68 static inline int rocker_tlv_padlen(int payload)
69 {
70 	return rocker_tlv_total_size(payload) - rocker_tlv_attr_size(payload);
71 }
72 
73 static inline int rocker_tlv_type(const struct rocker_tlv *tlv)
74 {
75 	return tlv->type;
76 }
77 
78 static inline void *rocker_tlv_data(const struct rocker_tlv *tlv)
79 {
80 	return (char *) tlv + ROCKER_TLV_HDRLEN;
81 }
82 
83 static inline int rocker_tlv_len(const struct rocker_tlv *tlv)
84 {
85 	return tlv->len - ROCKER_TLV_HDRLEN;
86 }
87 
88 static inline u8 rocker_tlv_get_u8(const struct rocker_tlv *tlv)
89 {
90 	return *(u8 *) rocker_tlv_data(tlv);
91 }
92 
93 static inline u16 rocker_tlv_get_u16(const struct rocker_tlv *tlv)
94 {
95 	return *(u16 *) rocker_tlv_data(tlv);
96 }
97 
98 static inline __be16 rocker_tlv_get_be16(const struct rocker_tlv *tlv)
99 {
100 	return *(__be16 *) rocker_tlv_data(tlv);
101 }
102 
103 static inline u32 rocker_tlv_get_u32(const struct rocker_tlv *tlv)
104 {
105 	return *(u32 *) rocker_tlv_data(tlv);
106 }
107 
108 static inline u64 rocker_tlv_get_u64(const struct rocker_tlv *tlv)
109 {
110 	return *(u64 *) rocker_tlv_data(tlv);
111 }
112 
113 void rocker_tlv_parse(const struct rocker_tlv **tb, int maxtype,
114 		      const char *buf, int buf_len);
115 
116 static inline void rocker_tlv_parse_nested(const struct rocker_tlv **tb,
117 					   int maxtype,
118 					   const struct rocker_tlv *tlv)
119 {
120 	rocker_tlv_parse(tb, maxtype, rocker_tlv_data(tlv),
121 			 rocker_tlv_len(tlv));
122 }
123 
124 static inline void
125 rocker_tlv_parse_desc(const struct rocker_tlv **tb, int maxtype,
126 		      const struct rocker_desc_info *desc_info)
127 {
128 	rocker_tlv_parse(tb, maxtype, desc_info->data,
129 			 desc_info->desc->tlv_size);
130 }
131 
132 static inline struct rocker_tlv *
133 rocker_tlv_start(struct rocker_desc_info *desc_info)
134 {
135 	return (struct rocker_tlv *) ((char *) desc_info->data +
136 					       desc_info->tlv_size);
137 }
138 
139 int rocker_tlv_put(struct rocker_desc_info *desc_info,
140 		   int attrtype, int attrlen, const void *data);
141 
142 static inline int rocker_tlv_put_u8(struct rocker_desc_info *desc_info,
143 				    int attrtype, u8 value)
144 {
145 	return rocker_tlv_put(desc_info, attrtype, sizeof(u8), &value);
146 }
147 
148 static inline int rocker_tlv_put_u16(struct rocker_desc_info *desc_info,
149 				     int attrtype, u16 value)
150 {
151 	return rocker_tlv_put(desc_info, attrtype, sizeof(u16), &value);
152 }
153 
154 static inline int rocker_tlv_put_be16(struct rocker_desc_info *desc_info,
155 				      int attrtype, __be16 value)
156 {
157 	return rocker_tlv_put(desc_info, attrtype, sizeof(__be16), &value);
158 }
159 
160 static inline int rocker_tlv_put_u32(struct rocker_desc_info *desc_info,
161 				     int attrtype, u32 value)
162 {
163 	return rocker_tlv_put(desc_info, attrtype, sizeof(u32), &value);
164 }
165 
166 static inline int rocker_tlv_put_be32(struct rocker_desc_info *desc_info,
167 				      int attrtype, __be32 value)
168 {
169 	return rocker_tlv_put(desc_info, attrtype, sizeof(__be32), &value);
170 }
171 
172 static inline int rocker_tlv_put_u64(struct rocker_desc_info *desc_info,
173 				     int attrtype, u64 value)
174 {
175 	return rocker_tlv_put(desc_info, attrtype, sizeof(u64), &value);
176 }
177 
178 static inline struct rocker_tlv *
179 rocker_tlv_nest_start(struct rocker_desc_info *desc_info, int attrtype)
180 {
181 	struct rocker_tlv *start = rocker_tlv_start(desc_info);
182 
183 	if (rocker_tlv_put(desc_info, attrtype, 0, NULL) < 0)
184 		return NULL;
185 
186 	return start;
187 }
188 
189 static inline void rocker_tlv_nest_end(struct rocker_desc_info *desc_info,
190 				       struct rocker_tlv *start)
191 {
192 	start->len = (char *) rocker_tlv_start(desc_info) - (char *) start;
193 }
194 
195 static inline void rocker_tlv_nest_cancel(struct rocker_desc_info *desc_info,
196 					  const struct rocker_tlv *start)
197 {
198 	desc_info->tlv_size = (const char *) start - desc_info->data;
199 }
200 
201 #endif
202