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/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright(c) 2007 Intel Corporation. All rights reserved.
*
* Maintained at www.Open-FCoE.org
*/
#ifndef _FC_ENCAPS_H_
#define _FC_ENCAPS_H_
/*
* Protocol definitions from RFC 3643 - Fibre Channel Frame Encapsulation.
*
* Note: The frame length field is the number of 32-bit words in
* the encapsulation including the fcip_encaps_header, CRC and EOF words.
* The minimum frame length value in bytes is (32 + 24 + 4 + 4) * 4 = 64.
* The maximum frame length value in bytes is (32 + 24 + 2112 + 4 + 4) = 2172.
*/
#define FC_ENCAPS_MIN_FRAME_LEN 64 /* min frame len (bytes) (see above) */
#define FC_ENCAPS_MAX_FRAME_LEN (FC_ENCAPS_MIN_FRAME_LEN + FC_MAX_PAYLOAD)
#define FC_ENCAPS_VER 1 /* current version number */
struct fc_encaps_hdr {
__u8 fc_proto; /* protocol number */
__u8 fc_ver; /* version of encapsulation */
__u8 fc_proto_n; /* ones complement of protocol */
__u8 fc_ver_n; /* ones complement of version */
unsigned char fc_proto_data[8]; /* protocol specific data */
__be16 fc_len_flags; /* 10-bit length/4 w/ 6 flag bits */
__be16 fc_len_flags_n; /* ones complement of length / flags */
/*
* Offset 0x10
*/
__be32 fc_time[2]; /* time stamp: seconds and fraction */
__be32 fc_crc; /* CRC */
__be32 fc_sof; /* start of frame (see FC_SOF below) */
/* 0x20 - FC frame content followed by EOF word */
};
#define FCIP_ENCAPS_HDR_LEN 0x20 /* expected length for asserts */
/*
* Macro's for making redundant copies of EOF and SOF.
*/
#define FC_XY(x, y) ((((x) & 0xff) << 8) | ((y) & 0xff))
#define FC_XYXY(x, y) ((FCIP_XY(x, y) << 16) | FCIP_XY(x, y))
#define FC_XYNN(x, y) (FCIP_XYXY(x, y) ^ 0xffff)
#define FC_SOF_ENCODE(n) FC_XYNN(n, n)
#define FC_EOF_ENCODE(n) FC_XYNN(n, n)
/*
* SOF / EOF bytes.
*/
enum fc_sof {
FC_SOF_F = 0x28, /* fabric */
FC_SOF_I4 = 0x29, /* initiate class 4 */
FC_SOF_I2 = 0x2d, /* initiate class 2 */
FC_SOF_I3 = 0x2e, /* initiate class 3 */
FC_SOF_N4 = 0x31, /* normal class 4 */
FC_SOF_N2 = 0x35, /* normal class 2 */
FC_SOF_N3 = 0x36, /* normal class 3 */
FC_SOF_C4 = 0x39, /* activate class 4 */
} __attribute__((packed));
enum fc_eof {
FC_EOF_N = 0x41, /* normal (not last frame of seq) */
FC_EOF_T = 0x42, /* terminate (last frame of sequence) */
FC_EOF_RT = 0x44,
FC_EOF_DT = 0x46, /* disconnect-terminate class-1 */
FC_EOF_NI = 0x49, /* normal-invalid */
FC_EOF_DTI = 0x4e, /* disconnect-terminate-invalid */
FC_EOF_RTI = 0x4f,
FC_EOF_A = 0x50, /* abort */
} __attribute__((packed));
#define FC_SOF_CLASS_MASK 0x06 /* mask for class of service in SOF */
/*
* Define classes in terms of the SOF code (initial).
*/
enum fc_class {
FC_CLASS_NONE = 0, /* software value indicating no class */
FC_CLASS_2 = FC_SOF_I2,
FC_CLASS_3 = FC_SOF_I3,
FC_CLASS_4 = FC_SOF_I4,
FC_CLASS_F = FC_SOF_F,
};
/*
* Determine whether SOF code indicates the need for a BLS ACK.
*/
static inline int fc_sof_needs_ack(enum fc_sof sof)
{
return (~sof) & 0x02; /* true for class 1, 2, 4, 6, or F */
}
/*
* Given an fc_class, return the normal (non-initial) SOF value.
*/
static inline enum fc_sof fc_sof_normal(enum fc_class class)
{
return class + FC_SOF_N3 - FC_SOF_I3; /* diff is always 8 */
}
/*
* Compute class from SOF value.
*/
static inline enum fc_class fc_sof_class(enum fc_sof sof)
{
return (sof & 0x7) | FC_SOF_F;
}
/*
* Determine whether SOF is for the initial frame of a sequence.
*/
static inline int fc_sof_is_init(enum fc_sof sof)
{
return sof < 0x30;
}
#endif /* _FC_ENCAPS_H_ */