1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
2 | /* |
3 | * Copyright(c) 2007 Intel Corporation. All rights reserved. |
4 | * |
5 | * Maintained at www.Open-FCoE.org |
6 | */ |
7 | #ifndef _FC_ENCAPS_H_ |
8 | #define _FC_ENCAPS_H_ |
9 | |
10 | /* |
11 | * Protocol definitions from RFC 3643 - Fibre Channel Frame Encapsulation. |
12 | * |
13 | * Note: The frame length field is the number of 32-bit words in |
14 | * the encapsulation including the fcip_encaps_header, CRC and EOF words. |
15 | * The minimum frame length value in bytes is (32 + 24 + 4 + 4) * 4 = 64. |
16 | * The maximum frame length value in bytes is (32 + 24 + 2112 + 4 + 4) = 2172. |
17 | */ |
18 | #define FC_ENCAPS_MIN_FRAME_LEN 64 /* min frame len (bytes) (see above) */ |
19 | #define FC_ENCAPS_MAX_FRAME_LEN (FC_ENCAPS_MIN_FRAME_LEN + FC_MAX_PAYLOAD) |
20 | |
21 | #define FC_ENCAPS_VER 1 /* current version number */ |
22 | |
23 | struct fc_encaps_hdr { |
24 | __u8 fc_proto; /* protocol number */ |
25 | __u8 fc_ver; /* version of encapsulation */ |
26 | __u8 fc_proto_n; /* ones complement of protocol */ |
27 | __u8 fc_ver_n; /* ones complement of version */ |
28 | |
29 | unsigned char fc_proto_data[8]; /* protocol specific data */ |
30 | |
31 | __be16 fc_len_flags; /* 10-bit length/4 w/ 6 flag bits */ |
32 | __be16 fc_len_flags_n; /* ones complement of length / flags */ |
33 | |
34 | /* |
35 | * Offset 0x10 |
36 | */ |
37 | __be32 fc_time[2]; /* time stamp: seconds and fraction */ |
38 | __be32 fc_crc; /* CRC */ |
39 | __be32 fc_sof; /* start of frame (see FC_SOF below) */ |
40 | |
41 | /* 0x20 - FC frame content followed by EOF word */ |
42 | }; |
43 | |
44 | #define FCIP_ENCAPS_HDR_LEN 0x20 /* expected length for asserts */ |
45 | |
46 | /* |
47 | * Macro's for making redundant copies of EOF and SOF. |
48 | */ |
49 | #define FC_XY(x, y) ((((x) & 0xff) << 8) | ((y) & 0xff)) |
50 | #define FC_XYXY(x, y) ((FCIP_XY(x, y) << 16) | FCIP_XY(x, y)) |
51 | #define FC_XYNN(x, y) (FCIP_XYXY(x, y) ^ 0xffff) |
52 | |
53 | #define FC_SOF_ENCODE(n) FC_XYNN(n, n) |
54 | #define FC_EOF_ENCODE(n) FC_XYNN(n, n) |
55 | |
56 | /* |
57 | * SOF / EOF bytes. |
58 | */ |
59 | enum fc_sof { |
60 | FC_SOF_F = 0x28, /* fabric */ |
61 | FC_SOF_I4 = 0x29, /* initiate class 4 */ |
62 | FC_SOF_I2 = 0x2d, /* initiate class 2 */ |
63 | FC_SOF_I3 = 0x2e, /* initiate class 3 */ |
64 | FC_SOF_N4 = 0x31, /* normal class 4 */ |
65 | FC_SOF_N2 = 0x35, /* normal class 2 */ |
66 | FC_SOF_N3 = 0x36, /* normal class 3 */ |
67 | FC_SOF_C4 = 0x39, /* activate class 4 */ |
68 | } __attribute__((packed)); |
69 | |
70 | enum fc_eof { |
71 | FC_EOF_N = 0x41, /* normal (not last frame of seq) */ |
72 | FC_EOF_T = 0x42, /* terminate (last frame of sequence) */ |
73 | FC_EOF_RT = 0x44, |
74 | FC_EOF_DT = 0x46, /* disconnect-terminate class-1 */ |
75 | FC_EOF_NI = 0x49, /* normal-invalid */ |
76 | FC_EOF_DTI = 0x4e, /* disconnect-terminate-invalid */ |
77 | FC_EOF_RTI = 0x4f, |
78 | FC_EOF_A = 0x50, /* abort */ |
79 | } __attribute__((packed)); |
80 | |
81 | #define FC_SOF_CLASS_MASK 0x06 /* mask for class of service in SOF */ |
82 | |
83 | /* |
84 | * Define classes in terms of the SOF code (initial). |
85 | */ |
86 | enum fc_class { |
87 | FC_CLASS_NONE = 0, /* software value indicating no class */ |
88 | FC_CLASS_2 = FC_SOF_I2, |
89 | FC_CLASS_3 = FC_SOF_I3, |
90 | FC_CLASS_4 = FC_SOF_I4, |
91 | FC_CLASS_F = FC_SOF_F, |
92 | }; |
93 | |
94 | /* |
95 | * Determine whether SOF code indicates the need for a BLS ACK. |
96 | */ |
97 | static inline int fc_sof_needs_ack(enum fc_sof sof) |
98 | { |
99 | return (~sof) & 0x02; /* true for class 1, 2, 4, 6, or F */ |
100 | } |
101 | |
102 | /* |
103 | * Given an fc_class, return the normal (non-initial) SOF value. |
104 | */ |
105 | static inline enum fc_sof fc_sof_normal(enum fc_class class) |
106 | { |
107 | return class + FC_SOF_N3 - FC_SOF_I3; /* diff is always 8 */ |
108 | } |
109 | |
110 | /* |
111 | * Compute class from SOF value. |
112 | */ |
113 | static inline enum fc_class fc_sof_class(enum fc_sof sof) |
114 | { |
115 | return (sof & 0x7) | FC_SOF_F; |
116 | } |
117 | |
118 | /* |
119 | * Determine whether SOF is for the initial frame of a sequence. |
120 | */ |
121 | static inline int fc_sof_is_init(enum fc_sof sof) |
122 | { |
123 | return sof < 0x30; |
124 | } |
125 | |
126 | #endif /* _FC_ENCAPS_H_ */ |
127 | |