/*
 * Copyright(c) 2007 Intel Corporation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Maintained at www.Open-FCoE.org
 */

#ifndef _FC_FCP_H_
#define _FC_FCP_H_

#include <scsi/scsi.h>

/*
 * Fibre Channel Protocol for SCSI.
 * From T10 FCP-3, T10 project 1560-D Rev 4, Sept. 13, 2005.
 */

/*
 * fc/fs.h defines FC_TYPE_FCP.
 */

/*
 * Service parameter page parameters (word 3 bits) for Process Login.
 */
#define FCP_SPPF_TASK_RETRY_ID  0x0200  /* task retry ID requested */
#define FCP_SPPF_RETRY          0x0100  /* retry supported */
#define FCP_SPPF_CONF_COMPL     0x0080  /* confirmed completion allowed */
#define FCP_SPPF_OVLY_ALLOW     0x0040  /* data overlay allowed */
#define FCP_SPPF_INIT_FCN       0x0020  /* initiator function */
#define FCP_SPPF_TARG_FCN       0x0010  /* target function */
#define FCP_SPPF_RD_XRDY_DIS    0x0002  /* disable XFER_RDY for reads */
#define FCP_SPPF_WR_XRDY_DIS    0x0001  /* disable XFER_RDY for writes */

/*
 * FCP_CMND IU Payload.
 */
struct fcp_cmnd {
        struct scsi_lun fc_lun;         /* logical unit number */
        __u8            fc_cmdref;      /* command reference number */
        __u8            fc_pri_ta;      /* priority and task attribute */
        __u8            fc_tm_flags;    /* task management flags */
        __u8            fc_flags;       /* additional len & flags */
        __u8            fc_cdb[16];     /* base CDB */
        __be32          fc_dl;          /* data length (must follow fc_cdb) */
};

#define FCP_CMND_LEN    32      /* expected length of structure */

struct fcp_cmnd32 {
        struct scsi_lun fc_lun;         /* logical unit number */
        __u8            fc_cmdref;      /* command reference number */
        __u8            fc_pri_ta;      /* priority and task attribute */
        __u8            fc_tm_flags;    /* task management flags */
        __u8            fc_flags;       /* additional len & flags */
        __u8            fc_cdb[32];     /* base CDB */
        __be32          fc_dl;          /* data length (must follow fc_cdb) */
};

#define FCP_CMND32_LEN      48  /* expected length of structure */
#define FCP_CMND32_ADD_LEN  (16 / 4)    /* Additional cdb length */

/*
 * fc_pri_ta.
 */
#define FCP_PTA_SIMPLE      0   /* simple task attribute */
#define FCP_PTA_HEADQ       1   /* head of queue task attribute */
#define FCP_PTA_ORDERED     2   /* ordered task attribute */
#define FCP_PTA_ACA         4   /* auto. contingent allegiance */
#define FCP_PTA_MASK        7   /* mask for task attribute field */
#define FCP_PRI_SHIFT       3   /* priority field starts in bit 3 */
#define FCP_PRI_RESVD_MASK  0x80        /* reserved bits in priority field */

/*
 * fc_tm_flags - task management flags field.
 */
#define FCP_TMF_CLR_ACA         0x40    /* clear ACA condition */
#define FCP_TMF_TGT_RESET       0x20    /* target reset task management,
                                           deprecated as of FCP-3 */
#define FCP_TMF_LUN_RESET       0x10    /* logical unit reset task management */
#define FCP_TMF_CLR_TASK_SET    0x04    /* clear task set */
#define FCP_TMF_ABT_TASK_SET    0x02    /* abort task set */

/*
 * fc_flags.
 *  Bits 7:2 are the additional FCP_CDB length / 4.
 */
#define FCP_CFL_LEN_MASK        0xfc    /* mask for additional length */
#define FCP_CFL_LEN_SHIFT       2       /* shift bits for additional length */
#define FCP_CFL_RDDATA          0x02    /* read data */
#define FCP_CFL_WRDATA          0x01    /* write data */

/*
 * FCP_TXRDY IU - transfer ready payload.
 */
struct fcp_txrdy {
        __be32          ft_data_ro;     /* data relative offset */
        __be32          ft_burst_len;   /* burst length */
        __u8            _ft_resvd[4];   /* reserved */
};

#define FCP_TXRDY_LEN   12      /* expected length of structure */

/*
 * FCP_RESP IU - response payload.
 *
 * The response payload comes in three parts: the flags/status, the
 * sense/response lengths and the sense data/response info section.
 *
 * From FCP3r04, note 6 of section 9.5.13:
 *
 * Some early implementations presented the FCP_RSP IU without the FCP_RESID,
 * FCP_SNS_LEN, and FCP_RSP_LEN fields if the FCP_RESID_UNDER, FCP_RESID_OVER,
 * FCP_SNS_LEN_VALID, and FCP_RSP_LEN_VALID bits were all set to zero. This
 * non-standard behavior should be tolerated.
 *
 * All response frames will always contain the fcp_resp template.  Some
 * will also include the fcp_resp_len template.
 *
 * From Table 23, the FCP_RSP_INFO can either be 4 bytes or 8 bytes, both
 * are valid length.
 */
struct fcp_resp {
        __u8            _fr_resvd[8];   /* reserved */
        __be16          fr_retry_delay; /* retry delay timer */
        __u8            fr_flags;       /* flags */
        __u8            fr_status;      /* SCSI status code */
};

#define FCP_RESP_LEN    12      /* expected length of structure */

struct fcp_resp_ext {
        __be32          fr_resid;       /* Residual value */
        __be32          fr_sns_len;     /* SCSI Sense length */
        __be32          fr_rsp_len;     /* Response Info length */

        /*
         * Optionally followed by RSP info and/or SNS info and/or
         * bidirectional read residual length, if any.
         */
};

#define FCP_RESP_EXT_LEN    12  /* expected length of the structure */

struct fcp_resp_rsp_info {
    __u8      _fr_resvd[3];       /* reserved */
    __u8      rsp_code;           /* Response Info Code */
    __u8      _fr_resvd2[4];      /* reserved */
};

#define FCP_RESP_RSP_INFO_LEN4    4 /* without reserved field */
#define FCP_RESP_RSP_INFO_LEN8    8 /* with reserved field */

struct fcp_resp_with_ext {
        struct fcp_resp resp;
        struct fcp_resp_ext ext;
};

#define FCP_RESP_WITH_EXT   (FCP_RESP_LEN + FCP_RESP_EXT_LEN)

/*
 * fr_flags.
 */
#define FCP_BIDI_RSP        0x80        /* bidirectional read response */
#define FCP_BIDI_READ_UNDER 0x40        /* bidir. read less than requested */
#define FCP_BIDI_READ_OVER  0x20        /* DL insufficient for full transfer */
#define FCP_CONF_REQ        0x10        /* confirmation requested */
#define FCP_RESID_UNDER     0x08        /* transfer shorter than expected */
#define FCP_RESID_OVER      0x04        /* DL insufficient for full transfer */
#define FCP_SNS_LEN_VAL     0x02        /* SNS_LEN field is valid */
#define FCP_RSP_LEN_VAL     0x01        /* RSP_LEN field is valid */

/*
 * rsp_codes
 */
enum fcp_resp_rsp_codes {
        FCP_TMF_CMPL = 0,
        FCP_DATA_LEN_INVALID = 1,
        FCP_CMND_FIELDS_INVALID = 2,
        FCP_DATA_PARAM_MISMATCH = 3,
        FCP_TMF_REJECTED = 4,
        FCP_TMF_FAILED = 5,
        FCP_TMF_INVALID_LUN = 9,
};

/*
 * FCP SRR Link Service request - Sequence Retransmission Request.
 */
struct fcp_srr {
        __u8            srr_op;         /* opcode ELS_SRR */
        __u8            srr_resvd[3];   /* opcode / reserved - must be zero */
        __be16          srr_ox_id;      /* OX_ID of failed command */
        __be16          srr_rx_id;      /* RX_ID of failed command */
        __be32          srr_rel_off;    /* relative offset */
        __u8            srr_r_ctl;      /* r_ctl for the information unit */
        __u8            srr_resvd2[3];  /* reserved */
};

/*
 * Feature bits in name server FC-4 Features object.
 */
#define FCP_FEAT_TARG   (1 << 0)        /* target function supported */
#define FCP_FEAT_INIT   (1 << 1)        /* initiator function supported */

#endif /* _FC_FCP_H_ */