/*
   * Copyright 2014 Cisco Systems, Inc.  All rights reserved.
   *
   * This program is free software; you may redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; version 2 of the License.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
   * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
   * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
   * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
   * SOFTWARE.
   */
  
  #ifndef __SNIC_FWINT_H
  #define __SNIC_FWINT_H
  
  #define SNIC_CDB_LEN	32	/* SCSI CDB size 32, can be used for 16 bytes */
  #define LUN_ADDR_LEN	8
  
  /*
   * Command entry type
   */
  enum snic_io_type {
  	/*
  	 * Initiator request types
  	 */
  	SNIC_REQ_REPORT_TGTS = 0x2,	/* Report Targets */
  	SNIC_REQ_ICMND,			/* Initiator command for SCSI IO */
  	SNIC_REQ_ITMF,			/* Initiator command for Task Mgmt */
  	SNIC_REQ_HBA_RESET,		/* SNIC Reset */
  	SNIC_REQ_EXCH_VER,		/* Exchange Version Information */
  	SNIC_REQ_TGT_INFO,		/* Backend/Target Information */
  	SNIC_REQ_BOOT_LUNS,
  
  	/*
  	 * Response type
  	 */
  	SNIC_RSP_REPORT_TGTS_CMPL = 0x12,/* Report Targets Completion */
  	SNIC_RSP_ICMND_CMPL,		/* SCSI IO Completion */
  	SNIC_RSP_ITMF_CMPL,		/* Task Management Completion */
  	SNIC_RSP_HBA_RESET_CMPL,	/* SNIC Reset Completion */
  	SNIC_RSP_EXCH_VER_CMPL,		/* Exchange Version Completion*/
  	SNIC_RSP_BOOT_LUNS_CMPL,
  
  	/*
  	 * Misc Request types
  	 */
  	SNIC_MSG_ACK = 0x80,		/* Ack: snic_notify_msg */
  	SNIC_MSG_ASYNC_EVNOTIFY,	/* Asynchronous Event Notification */
  }; /* end of enum snic_io_type */
  
  
  /*
   * Header status codes from firmware
   */
  enum snic_io_status {
  	SNIC_STAT_IO_SUCCESS = 0,	/* request was successful */
  
  	/*
  	 * If a request to the fw is rejected, the original request header
  	 * will be returned with the status set to one of the following:
  	 */
  	SNIC_STAT_INVALID_HDR,	/* header contains invalid data */
  	SNIC_STAT_OUT_OF_RES,	/* out of resources to complete request */
  	SNIC_STAT_INVALID_PARM,	/* some parameter in request is not valid */
  	SNIC_STAT_REQ_NOT_SUP,	/* req type is not supported */
  	SNIC_STAT_IO_NOT_FOUND,	/* requested IO was not found */
  
  	/*
  	 * Once a request is processed, the fw will usually return
  	 * a cmpl message type. In cases where errors occurred,
  	 * the header status would be filled in with one of the following:
  	 */
  	SNIC_STAT_ABORTED,		/* req was aborted */
  	SNIC_STAT_TIMEOUT,		/* req was timed out */
  	SNIC_STAT_SGL_INVALID,		/* req was aborted due to sgl error */
  	SNIC_STAT_DATA_CNT_MISMATCH,	/*recv/sent more/less data than expec */
  	SNIC_STAT_FW_ERR,		/* req was terminated due to fw error */
  	SNIC_STAT_ITMF_REJECT,		/* itmf req was rejected by target */
  	SNIC_STAT_ITMF_FAIL,		/* itmf req was failed */
  	SNIC_STAT_ITMF_INCORRECT_LUN,	/* itmf req has incorrect LUN id*/
  	SNIC_STAT_CMND_REJECT,		/* req was invalid and rejected */
  	SNIC_STAT_DEV_OFFLINE,		/* req sent to offline device */
  	SNIC_STAT_NO_BOOTLUN,
  	SNIC_STAT_SCSI_ERR,		/* SCSI error returned by Target. */
  	SNIC_STAT_NOT_READY,		/* sNIC Subsystem is not ready */
  	SNIC_STAT_FATAL_ERROR,		/* sNIC is in unrecoverable state */
  }; /* end of enum snic_io_status */
  
  /*
   * snic_io_hdr : host <--> firmare
   *
   * for any other message that will be queued to firmware should
   *  have the following request header
   */
  struct snic_io_hdr {
  	__le32	hid;
  	__le32	cmnd_id;	/* tag here */
  	ulong	init_ctx;	/* initiator context */
  	u8	type;		/* request/response type */
  	u8	status;		/* header status entry */
  	u8	protocol;	/* Protocol specific, may needed for RoCE*/
  	u8	flags;
  	__le16	sg_cnt;
  	u16	resvd;
  };
  
  /* auxillary funciton for encoding the snic_io_hdr */
  static inline void
  snic_io_hdr_enc(struct snic_io_hdr *hdr, u8 typ, u8 status, u32 id, u32 hid,
  		u16 sg_cnt, ulong ctx)
  {
  	hdr->type = typ;
  	hdr->status = status;
  	hdr->protocol = 0;
  	hdr->hid = cpu_to_le32(hid);
  	hdr->cmnd_id = cpu_to_le32(id);
  	hdr->sg_cnt = cpu_to_le16(sg_cnt);
  	hdr->init_ctx = ctx;
  	hdr->flags = 0;
  }
  
  /* auxillary funciton for decoding the snic_io_hdr */
  static inline void
  snic_io_hdr_dec(struct snic_io_hdr *hdr, u8 *typ, u8 *stat, u32 *cmnd_id,
  		u32 *hid, ulong *ctx)
  {
  	*typ = hdr->type;
  	*stat = hdr->status;
  	*hid = le32_to_cpu(hdr->hid);
  	*cmnd_id = le32_to_cpu(hdr->cmnd_id);
  	*ctx = hdr->init_ctx;
  }
  
  /*
   * snic_host_info: host -> firmware
   *
   * Used for sending host information to firmware, and request fw version
   */
  struct snic_exch_ver_req {
  	__le32	drvr_ver;	/* for debugging, when fw dump captured */
  	__le32	os_type;	/* for OS specific features */
  };
  
  /*
   * os_type flags
   * Bit 0-7 : OS information
   * Bit 8-31: Feature/Capability Information
   */
  #define SNIC_OS_LINUX	0x1
  #define SNIC_OS_WIN	0x2
  #define SNIC_OS_ESX	0x3
  
  /*
   * HBA Capabilities
   * Bit 1: Reserved.
   * Bit 2: Dynamic Discovery of LUNs.
   * Bit 3: Async event notifications on on tgt online/offline events.
   * Bit 4: IO timeout support in FW.
   * Bit 5-31: Reserved.
   */
  #define SNIC_HBA_CAP_DDL	0x02	/* Supports Dynamic Discovery of LUNs */
  #define SNIC_HBA_CAP_AEN	0x04	/* Supports Async Event Noitifcation */
  #define SNIC_HBA_CAP_TMO	0x08	/* Supports IO timeout in FW */
  
  /*
   * snic_exch_ver_rsp : firmware -> host
   *
   * Used by firmware to send response to version request
   */
  struct snic_exch_ver_rsp {
  	__le32	version;
  	__le32	hid;
  	__le32	max_concur_ios;		/* max concurrent ios */
  	__le32	max_sgs_per_cmd;	/* max sgls per IO */
  	__le32	max_io_sz;		/* max io size supported */
  	__le32	hba_cap;		/* hba capabilities */
  	__le32	max_tgts;		/* max tgts supported */
  	__le16	io_timeout;		/* FW extended timeout */
  	u16	rsvd;
  };
  
  
  /*
   * snic_report_tgts : host -> firmware request
   *
   * Used by the host to request list of targets
   */
  struct snic_report_tgts {
  	__le16	sg_cnt;
  	__le16	flags;		/* specific flags from fw */
  	u8	_resvd[4];
  	__le64	sg_addr;	/* Points to SGL */
  	__le64	sense_addr;
  };
  
  enum snic_type {
  	SNIC_NONE = 0x0,
  	SNIC_DAS,
  	SNIC_SAN,
  };
  
  
  /* Report Target Response */
  enum snic_tgt_type {
  	SNIC_TGT_NONE = 0x0,
  	SNIC_TGT_DAS,	/* DAS Target */
  	SNIC_TGT_SAN,	/* SAN Target */
  };
  
  /* target id format */
  struct snic_tgt_id {
  	__le32	tgt_id;		/* target id */
  	__le16	tgt_type;	/* tgt type */
  	__le16	vnic_id;	/* corresponding vnic id */
  };
  
  /*
   * snic_report_tgts_cmpl : firmware -> host response
   *
   * Used by firmware to send response to Report Targets request
   */
  struct snic_report_tgts_cmpl {
  	__le32	tgt_cnt;	/* Number of Targets accessible */
  	u32	_resvd;
  };
  
  /*
   * Command flags
   *
   * Bit 0: Read flags
   * Bit 1: Write flag
   * Bit 2: ESGL - sg/esg array contains extended sg
   *	  ESGE - is a host buffer contains sg elements
   * Bit 3-4: Task Attributes
   *		00b - simple
   *		01b - head of queue
   *		10b - ordered
   * Bit 5-7: Priority - future use
   * Bit 8-15: Reserved
   */
  
  #define SNIC_ICMND_WR		0x01	/* write command */
  #define SNIC_ICMND_RD		0x02	/* read command */
  #define SNIC_ICMND_ESGL		0x04	/* SGE/ESGE array contains valid data*/
  
  /*
   * Priority/Task Attribute settings
   */
  #define SNIC_ICMND_TSK_SHIFT		2	/* task attr starts at bit 2 */
  #define SNIC_ICMND_TSK_MASK(x)		((x>>SNIC_ICMND_TSK_SHIFT) & ~(0xffff))
  #define SNIC_ICMND_TSK_SIMPLE		0	/* simple task attr */
  #define SNIC_ICMND_TSK_HEAD_OF_QUEUE	1	/* head of qeuue task attr */
  #define SNIC_ICMND_TSK_ORDERED		2	/* ordered task attr */
  
  #define SNIC_ICMND_PRI_SHIFT		5	/* prio val starts at bit 5 */
  
  /*
   * snic_icmnd : host-> firmware request
   *
   * used for sending out an initiator SCSI 16/32-byte command
   */
  struct snic_icmnd {
  	__le16	sg_cnt;		/* Number of SG Elements */
  	__le16	flags;		/* flags */
  	__le32	sense_len;	/* Sense buffer length */
  	__le64	tgt_id;		/* Destination Target ID */
  	__le64	lun_id;		/* Destination LUN ID */
  	u8	cdb_len;
  	u8	_resvd;
  	__le16	time_out;	/* ms time for Res allocations fw to handle io*/
  	__le32	data_len;	/* Total number of bytes to be transferred */
  	u8	cdb[SNIC_CDB_LEN];
  	__le64	sg_addr;	/* Points to SG List */
  	__le64	sense_addr;	/* Sense buffer address */
  };
  
  
  /* Response flags */
  /* Bit 0: Under run
   * Bit 1: Over Run
   * Bit 2-7: Reserved
   */
  #define SNIC_ICMND_CMPL_UNDR_RUN	0x01	/* resid under and valid */
  #define SNIC_ICMND_CMPL_OVER_RUN	0x02	/* resid over and valid */
  
  /*
   * snic_icmnd_cmpl: firmware -> host response
   *
   * Used for sending the host a response to an icmnd (initiator command)
   */
  struct snic_icmnd_cmpl {
  	u8	scsi_status;	/* value as per SAM */
  	u8	flags;
  	__le16	sense_len;	/* Sense Length */
  	__le32	resid;		/* Residue : # bytes under or over run */
  };
  
  /*
   * snic_itmf: host->firmware request
   *
   * used for requesting the firmware to abort a request and/or send out
   * a task management function
   *
   * the req_id field is valid in case of abort task and clear task
   */
  struct snic_itmf {
  	u8	tm_type;	/* SCSI Task Management request */
  	u8	resvd;
  	__le16	flags;		/* flags */
  	__le32	req_id;		/* Command id of snic req to be aborted */
  	__le64	tgt_id;		/* Target ID */
  	__le64	lun_id;		/* Destination LUN ID */
  	__le16	timeout;	/* in sec */
  };
  
  /*
   * Task Management Request
   */
  enum snic_itmf_tm_type {
  	SNIC_ITMF_ABTS_TASK = 0x01,	/* Abort Task */
  	SNIC_ITMF_ABTS_TASK_SET,	/* Abort Task Set */
  	SNIC_ITMF_CLR_TASK,		/* Clear Task */
  	SNIC_ITMF_CLR_TASKSET,		/* Clear Task Set */
  	SNIC_ITMF_LUN_RESET,		/* Lun Reset */
  	SNIC_ITMF_ABTS_TASK_TERM,	/* Supported for SAN Targets */
  };
  
  /*
   * snic_itmf_cmpl: firmware -> host resposne
   *
   * used for sending the host a response for a itmf request
   */
  struct snic_itmf_cmpl {
  	__le32	nterminated;	/* # IOs terminated as a result of tmf */
  	u8	flags;		/* flags */
  	u8	_resvd[3];
  };
  
  /*
   * itmfl_cmpl flags
   * Bit 0 : 1 - Num terminated field valid
   * Bit 1 - 7 : Reserved
   */
  #define SNIC_NUM_TERM_VALID	0x01	/* Number of IOs terminated */
  
  /*
   * snic_hba_reset: host -> firmware request
   *
   * used for requesting firmware to reset snic
   */
  struct snic_hba_reset {
  	__le16	flags;		/* flags */
  	u8	_resvd[6];
  };
  
  /*
   * snic_hba_reset_cmpl: firmware -> host response
   *
   * Used by firmware to respond to the host's hba reset request
   */
  struct snic_hba_reset_cmpl {
  	u8	flags;		/* flags : more info needs to be added*/
  	u8	_resvd[7];
  };
  
  /*
   * snic_notify_msg: firmware -> host response
   *
   * Used by firmware to notify host of the last work queue entry received
   */
  struct snic_notify_msg {
  	__le32	wqe_num;	/* wq entry number */
  	u8	flags;		/* flags, macros */
  	u8	_resvd[4];
  };
  
  
  #define SNIC_EVDATA_LEN		24	/* in bytes */
  /* snic_async_evnotify: firmware -> host notification
   *
   * Used by firmware to notify the host about configuration/state changes
   */
  struct snic_async_evnotify {
  	u8	FLS_EVENT_DESC;
  	u8	vnic;			/* vnic id */
  	u8	_resvd[2];
  	__le32	ev_id;			/* Event ID */
  	u8	ev_data[SNIC_EVDATA_LEN]; /* Event Data */
  	u8	_resvd2[4];
  };
  
  /* async event flags */
  enum snic_ev_type {
  	SNIC_EV_TGT_OFFLINE = 0x01, /* Target Offline, PL contains TGT ID */
  	SNIC_EV_TGT_ONLINE,	/* Target Online, PL contains TGT ID */
  	SNIC_EV_LUN_OFFLINE,	/* LUN Offline, PL contains LUN ID */
  	SNIC_EV_LUN_ONLINE,	/* LUN Online, PL contains LUN ID */
  	SNIC_EV_CONF_CHG,	/* Dev Config/Attr Change Event */
  	SNIC_EV_TGT_ADDED,	/* Target Added */
  	SNIC_EV_TGT_DELTD,	/* Target Del'd, PL contains TGT ID */
  	SNIC_EV_LUN_ADDED,	/* LUN Added */
  	SNIC_EV_LUN_DELTD,	/* LUN Del'd, PL cont. TGT & LUN ID */
  
  	SNIC_EV_DISC_CMPL = 0x10, /* Discovery Completed Event */
  };
  
  
  #define SNIC_HOST_REQ_LEN	128	/*Exp length of host req, wq desc sz*/
  /* Payload 88 bytes = 128 - 24 - 16 */
  #define SNIC_HOST_REQ_PAYLOAD	((int)(SNIC_HOST_REQ_LEN -		\
  					sizeof(struct snic_io_hdr) -	\
  					(2 * sizeof(u64))))
  
  /*
   * snic_host_req: host -> firmware request
   *
   * Basic structure for all snic requests that are sent from the host to
   * firmware. They are 128 bytes in size.
   */
  struct snic_host_req {
  	u64	ctrl_data[2];	/*16 bytes - Control Data */
  	struct snic_io_hdr hdr;
  	union {
  		/*
  		 * Entry specific space, last byte contains color
  		 */
  		u8	buf[SNIC_HOST_REQ_PAYLOAD];
  
  		/*
  		 * Exchange firmware version
  		 */
  		struct snic_exch_ver_req	exch_ver;
  
  		/* report targets */
  		struct snic_report_tgts		rpt_tgts;
  
  		/* io request */
  		struct snic_icmnd		icmnd;
  
  		/* task management request */
  		struct snic_itmf		itmf;
  
  		/* hba reset */
  		struct snic_hba_reset		reset;
  	} u;
  }; /* end of snic_host_req structure */
  
  
  #define SNIC_FW_REQ_LEN		64 /* Expected length of fw req */
  struct snic_fw_req {
  	struct snic_io_hdr hdr;
  	union {
  		/*
  		 * Entry specific space, last byte contains color
  		 */
  		u8	buf[SNIC_FW_REQ_LEN - sizeof(struct snic_io_hdr)];
  
  		/* Exchange Version Response */
  		struct snic_exch_ver_rsp	exch_ver_cmpl;
  
  		/* Report Targets Response */
  		struct snic_report_tgts_cmpl	rpt_tgts_cmpl;
  
  		/* scsi response */
  		struct snic_icmnd_cmpl		icmnd_cmpl;
  
  		/* task management response */
  		struct snic_itmf_cmpl		itmf_cmpl;
  
  		/* hba reset response */
  		struct snic_hba_reset_cmpl	reset_cmpl;
  
  		/* notify message */
  		struct snic_notify_msg		ack;
  
  		/* async notification event */
  		struct snic_async_evnotify	async_ev;
  
  	} u;
  }; /* end of snic_fw_req structure */
  
  /*
   * Auxillary macro to verify specific snic req/cmpl structures
   * to ensure that it will be aligned to 64 bit, and not using
   * color bit field
   */
  #define VERIFY_REQ_SZ(x)
  #define VERIFY_CMPL_SZ(x)
  
  /*
   * Access routines to encode and decode the color bit, which is the most
   * significant bit of the structure.
   */
  static inline void
  snic_color_enc(struct snic_fw_req *req, u8 color)
  {
  	u8 *c = ((u8 *) req) + sizeof(struct snic_fw_req) - 1;
  
  	if (color)
  		*c |= 0x80;
  	else
  		*c &= ~0x80;
  }
  
  static inline void
  snic_color_dec(struct snic_fw_req *req, u8 *color)
  {
  	u8 *c = ((u8 *) req) + sizeof(struct snic_fw_req) - 1;
  
  	*color = *c >> 7;
  
  	/* Make sure color bit is read from desc *before* other fields
  	 * are read from desc. Hardware guarantees color bit is last
  	 * bit (byte) written. Adding the rmb() prevents the compiler
  	 * and/or CPU from reordering the reads which would potentially
  	 * result in reading stale values.
  	 */
  	rmb();
  }
  #endif /* end of __SNIC_FWINT_H */