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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.org6 */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 in14 * 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 23struct 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 0x1036 */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 */59enum 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 70enum 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 */86enum 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 */97static 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 */105static 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 */113static 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 */121static inline int fc_sof_is_init(enum fc_sof sof)122{123 return sof < 0x30;124}125 126#endif /* _FC_ENCAPS_H_ */127