1 /* 2 * Copyright(c) 2007 Intel Corporation. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or modify it 5 * under the terms and conditions of the GNU General Public License, 6 * version 2, as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 11 * more details. 12 * 13 * You should have received a copy of the GNU General Public License along with 14 * this program; if not, write to the Free Software Foundation, Inc., 15 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. 16 * 17 * Maintained at www.Open-FCoE.org 18 */ 19 #ifndef _FC_ENCAPS_H_ 20 #define _FC_ENCAPS_H_ 21 22 /* 23 * Protocol definitions from RFC 3643 - Fibre Channel Frame Encapsulation. 24 * 25 * Note: The frame length field is the number of 32-bit words in 26 * the encapsulation including the fcip_encaps_header, CRC and EOF words. 27 * The minimum frame length value in bytes is (32 + 24 + 4 + 4) * 4 = 64. 28 * The maximum frame length value in bytes is (32 + 24 + 2112 + 4 + 4) = 2172. 29 */ 30 #define FC_ENCAPS_MIN_FRAME_LEN 64 /* min frame len (bytes) (see above) */ 31 #define FC_ENCAPS_MAX_FRAME_LEN (FC_ENCAPS_MIN_FRAME_LEN + FC_MAX_PAYLOAD) 32 33 #define FC_ENCAPS_VER 1 /* current version number */ 34 35 struct fc_encaps_hdr { 36 __u8 fc_proto; /* protocol number */ 37 __u8 fc_ver; /* version of encapsulation */ 38 __u8 fc_proto_n; /* ones complement of protocol */ 39 __u8 fc_ver_n; /* ones complement of version */ 40 41 unsigned char fc_proto_data[8]; /* protocol specific data */ 42 43 __be16 fc_len_flags; /* 10-bit length/4 w/ 6 flag bits */ 44 __be16 fc_len_flags_n; /* ones complement of length / flags */ 45 46 /* 47 * Offset 0x10 48 */ 49 __be32 fc_time[2]; /* time stamp: seconds and fraction */ 50 __be32 fc_crc; /* CRC */ 51 __be32 fc_sof; /* start of frame (see FC_SOF below) */ 52 53 /* 0x20 - FC frame content followed by EOF word */ 54 }; 55 56 #define FCIP_ENCAPS_HDR_LEN 0x20 /* expected length for asserts */ 57 58 /* 59 * Macro's for making redundant copies of EOF and SOF. 60 */ 61 #define FC_XY(x, y) ((((x) & 0xff) << 8) | ((y) & 0xff)) 62 #define FC_XYXY(x, y) ((FCIP_XY(x, y) << 16) | FCIP_XY(x, y)) 63 #define FC_XYNN(x, y) (FCIP_XYXY(x, y) ^ 0xffff) 64 65 #define FC_SOF_ENCODE(n) FC_XYNN(n, n) 66 #define FC_EOF_ENCODE(n) FC_XYNN(n, n) 67 68 /* 69 * SOF / EOF bytes. 70 */ 71 enum fc_sof { 72 FC_SOF_F = 0x28, /* fabric */ 73 FC_SOF_I4 = 0x29, /* initiate class 4 */ 74 FC_SOF_I2 = 0x2d, /* initiate class 2 */ 75 FC_SOF_I3 = 0x2e, /* initiate class 3 */ 76 FC_SOF_N4 = 0x31, /* normal class 4 */ 77 FC_SOF_N2 = 0x35, /* normal class 2 */ 78 FC_SOF_N3 = 0x36, /* normal class 3 */ 79 FC_SOF_C4 = 0x39, /* activate class 4 */ 80 } __attribute__((packed)); 81 82 enum fc_eof { 83 FC_EOF_N = 0x41, /* normal (not last frame of seq) */ 84 FC_EOF_T = 0x42, /* terminate (last frame of sequence) */ 85 FC_EOF_RT = 0x44, 86 FC_EOF_DT = 0x46, /* disconnect-terminate class-1 */ 87 FC_EOF_NI = 0x49, /* normal-invalid */ 88 FC_EOF_DTI = 0x4e, /* disconnect-terminate-invalid */ 89 FC_EOF_RTI = 0x4f, 90 FC_EOF_A = 0x50, /* abort */ 91 } __attribute__((packed)); 92 93 #define FC_SOF_CLASS_MASK 0x06 /* mask for class of service in SOF */ 94 95 /* 96 * Define classes in terms of the SOF code (initial). 97 */ 98 enum fc_class { 99 FC_CLASS_NONE = 0, /* software value indicating no class */ 100 FC_CLASS_2 = FC_SOF_I2, 101 FC_CLASS_3 = FC_SOF_I3, 102 FC_CLASS_4 = FC_SOF_I4, 103 FC_CLASS_F = FC_SOF_F, 104 }; 105 106 /* 107 * Determine whether SOF code indicates the need for a BLS ACK. 108 */ 109 static inline int fc_sof_needs_ack(enum fc_sof sof) 110 { 111 return (~sof) & 0x02; /* true for class 1, 2, 4, 6, or F */ 112 } 113 114 /* 115 * Given an fc_class, return the normal (non-initial) SOF value. 116 */ 117 static inline enum fc_sof fc_sof_normal(enum fc_class class) 118 { 119 return class + FC_SOF_N3 - FC_SOF_I3; /* diff is always 8 */ 120 } 121 122 /* 123 * Compute class from SOF value. 124 */ 125 static inline enum fc_class fc_sof_class(enum fc_sof sof) 126 { 127 return (sof & 0x7) | FC_SOF_F; 128 } 129 130 /* 131 * Determine whether SOF is for the initial frame of a sequence. 132 */ 133 static inline int fc_sof_is_init(enum fc_sof sof) 134 { 135 return sof < 0x30; 136 } 137 138 #endif /* _FC_ENCAPS_H_ */ 139