1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0-only */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Copyright(c) 2007 Intel Corporation. All rights reserved.
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Maintained at www.Open-FCoE.org
6*4882a593Smuzhiyun */
7*4882a593Smuzhiyun #ifndef _FC_ENCAPS_H_
8*4882a593Smuzhiyun #define _FC_ENCAPS_H_
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun /*
11*4882a593Smuzhiyun * Protocol definitions from RFC 3643 - Fibre Channel Frame Encapsulation.
12*4882a593Smuzhiyun *
13*4882a593Smuzhiyun * Note: The frame length field is the number of 32-bit words in
14*4882a593Smuzhiyun * the encapsulation including the fcip_encaps_header, CRC and EOF words.
15*4882a593Smuzhiyun * The minimum frame length value in bytes is (32 + 24 + 4 + 4) * 4 = 64.
16*4882a593Smuzhiyun * The maximum frame length value in bytes is (32 + 24 + 2112 + 4 + 4) = 2172.
17*4882a593Smuzhiyun */
18*4882a593Smuzhiyun #define FC_ENCAPS_MIN_FRAME_LEN 64 /* min frame len (bytes) (see above) */
19*4882a593Smuzhiyun #define FC_ENCAPS_MAX_FRAME_LEN (FC_ENCAPS_MIN_FRAME_LEN + FC_MAX_PAYLOAD)
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun #define FC_ENCAPS_VER 1 /* current version number */
22*4882a593Smuzhiyun
23*4882a593Smuzhiyun struct fc_encaps_hdr {
24*4882a593Smuzhiyun __u8 fc_proto; /* protocol number */
25*4882a593Smuzhiyun __u8 fc_ver; /* version of encapsulation */
26*4882a593Smuzhiyun __u8 fc_proto_n; /* ones complement of protocol */
27*4882a593Smuzhiyun __u8 fc_ver_n; /* ones complement of version */
28*4882a593Smuzhiyun
29*4882a593Smuzhiyun unsigned char fc_proto_data[8]; /* protocol specific data */
30*4882a593Smuzhiyun
31*4882a593Smuzhiyun __be16 fc_len_flags; /* 10-bit length/4 w/ 6 flag bits */
32*4882a593Smuzhiyun __be16 fc_len_flags_n; /* ones complement of length / flags */
33*4882a593Smuzhiyun
34*4882a593Smuzhiyun /*
35*4882a593Smuzhiyun * Offset 0x10
36*4882a593Smuzhiyun */
37*4882a593Smuzhiyun __be32 fc_time[2]; /* time stamp: seconds and fraction */
38*4882a593Smuzhiyun __be32 fc_crc; /* CRC */
39*4882a593Smuzhiyun __be32 fc_sof; /* start of frame (see FC_SOF below) */
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun /* 0x20 - FC frame content followed by EOF word */
42*4882a593Smuzhiyun };
43*4882a593Smuzhiyun
44*4882a593Smuzhiyun #define FCIP_ENCAPS_HDR_LEN 0x20 /* expected length for asserts */
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun /*
47*4882a593Smuzhiyun * Macro's for making redundant copies of EOF and SOF.
48*4882a593Smuzhiyun */
49*4882a593Smuzhiyun #define FC_XY(x, y) ((((x) & 0xff) << 8) | ((y) & 0xff))
50*4882a593Smuzhiyun #define FC_XYXY(x, y) ((FCIP_XY(x, y) << 16) | FCIP_XY(x, y))
51*4882a593Smuzhiyun #define FC_XYNN(x, y) (FCIP_XYXY(x, y) ^ 0xffff)
52*4882a593Smuzhiyun
53*4882a593Smuzhiyun #define FC_SOF_ENCODE(n) FC_XYNN(n, n)
54*4882a593Smuzhiyun #define FC_EOF_ENCODE(n) FC_XYNN(n, n)
55*4882a593Smuzhiyun
56*4882a593Smuzhiyun /*
57*4882a593Smuzhiyun * SOF / EOF bytes.
58*4882a593Smuzhiyun */
59*4882a593Smuzhiyun enum fc_sof {
60*4882a593Smuzhiyun FC_SOF_F = 0x28, /* fabric */
61*4882a593Smuzhiyun FC_SOF_I4 = 0x29, /* initiate class 4 */
62*4882a593Smuzhiyun FC_SOF_I2 = 0x2d, /* initiate class 2 */
63*4882a593Smuzhiyun FC_SOF_I3 = 0x2e, /* initiate class 3 */
64*4882a593Smuzhiyun FC_SOF_N4 = 0x31, /* normal class 4 */
65*4882a593Smuzhiyun FC_SOF_N2 = 0x35, /* normal class 2 */
66*4882a593Smuzhiyun FC_SOF_N3 = 0x36, /* normal class 3 */
67*4882a593Smuzhiyun FC_SOF_C4 = 0x39, /* activate class 4 */
68*4882a593Smuzhiyun } __attribute__((packed));
69*4882a593Smuzhiyun
70*4882a593Smuzhiyun enum fc_eof {
71*4882a593Smuzhiyun FC_EOF_N = 0x41, /* normal (not last frame of seq) */
72*4882a593Smuzhiyun FC_EOF_T = 0x42, /* terminate (last frame of sequence) */
73*4882a593Smuzhiyun FC_EOF_RT = 0x44,
74*4882a593Smuzhiyun FC_EOF_DT = 0x46, /* disconnect-terminate class-1 */
75*4882a593Smuzhiyun FC_EOF_NI = 0x49, /* normal-invalid */
76*4882a593Smuzhiyun FC_EOF_DTI = 0x4e, /* disconnect-terminate-invalid */
77*4882a593Smuzhiyun FC_EOF_RTI = 0x4f,
78*4882a593Smuzhiyun FC_EOF_A = 0x50, /* abort */
79*4882a593Smuzhiyun } __attribute__((packed));
80*4882a593Smuzhiyun
81*4882a593Smuzhiyun #define FC_SOF_CLASS_MASK 0x06 /* mask for class of service in SOF */
82*4882a593Smuzhiyun
83*4882a593Smuzhiyun /*
84*4882a593Smuzhiyun * Define classes in terms of the SOF code (initial).
85*4882a593Smuzhiyun */
86*4882a593Smuzhiyun enum fc_class {
87*4882a593Smuzhiyun FC_CLASS_NONE = 0, /* software value indicating no class */
88*4882a593Smuzhiyun FC_CLASS_2 = FC_SOF_I2,
89*4882a593Smuzhiyun FC_CLASS_3 = FC_SOF_I3,
90*4882a593Smuzhiyun FC_CLASS_4 = FC_SOF_I4,
91*4882a593Smuzhiyun FC_CLASS_F = FC_SOF_F,
92*4882a593Smuzhiyun };
93*4882a593Smuzhiyun
94*4882a593Smuzhiyun /*
95*4882a593Smuzhiyun * Determine whether SOF code indicates the need for a BLS ACK.
96*4882a593Smuzhiyun */
fc_sof_needs_ack(enum fc_sof sof)97*4882a593Smuzhiyun static inline int fc_sof_needs_ack(enum fc_sof sof)
98*4882a593Smuzhiyun {
99*4882a593Smuzhiyun return (~sof) & 0x02; /* true for class 1, 2, 4, 6, or F */
100*4882a593Smuzhiyun }
101*4882a593Smuzhiyun
102*4882a593Smuzhiyun /*
103*4882a593Smuzhiyun * Given an fc_class, return the normal (non-initial) SOF value.
104*4882a593Smuzhiyun */
fc_sof_normal(enum fc_class class)105*4882a593Smuzhiyun static inline enum fc_sof fc_sof_normal(enum fc_class class)
106*4882a593Smuzhiyun {
107*4882a593Smuzhiyun return class + FC_SOF_N3 - FC_SOF_I3; /* diff is always 8 */
108*4882a593Smuzhiyun }
109*4882a593Smuzhiyun
110*4882a593Smuzhiyun /*
111*4882a593Smuzhiyun * Compute class from SOF value.
112*4882a593Smuzhiyun */
fc_sof_class(enum fc_sof sof)113*4882a593Smuzhiyun static inline enum fc_class fc_sof_class(enum fc_sof sof)
114*4882a593Smuzhiyun {
115*4882a593Smuzhiyun return (sof & 0x7) | FC_SOF_F;
116*4882a593Smuzhiyun }
117*4882a593Smuzhiyun
118*4882a593Smuzhiyun /*
119*4882a593Smuzhiyun * Determine whether SOF is for the initial frame of a sequence.
120*4882a593Smuzhiyun */
fc_sof_is_init(enum fc_sof sof)121*4882a593Smuzhiyun static inline int fc_sof_is_init(enum fc_sof sof)
122*4882a593Smuzhiyun {
123*4882a593Smuzhiyun return sof < 0x30;
124*4882a593Smuzhiyun }
125*4882a593Smuzhiyun
126*4882a593Smuzhiyun #endif /* _FC_ENCAPS_H_ */
127