freebsd-skq/sys/dev/isp/isp_tpublic.h
2000-04-21 02:05:54 +00:00

330 lines
13 KiB
C

/* $FreeBSD$ */
/*
* Qlogic ISP Host Adapter Public Target Interface Structures && Routines
*---------------------------------------
* Copyright (c) 2000 by Matthew Jacob
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification, immediately at the beginning of the file.
* 2. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* Matthew Jacob
* Feral Software
* mjacob@feral.com
*/
/*
* Required software target mode message and event handling structures.
*
* The message and event structures are used by the MI layer
* to propagate messages and events upstream.
*/
#ifndef IN_MSGLEN
#define IN_MSGLEN 8
#endif
typedef struct {
void * nt_hba; /* HBA tag */
u_int64_t nt_iid; /* inititator id */
u_int64_t nt_tgt; /* target id */
u_int64_t nt_lun; /* logical unit */
u_int8_t nt_bus; /* bus */
u_int8_t nt_tagtype; /* tag type */
u_int16_t nt_tagval; /* tag value */
u_int8_t nt_msg[IN_MSGLEN]; /* message content */
} tmd_msg_t;
typedef struct {
void * ev_hba; /* HBA tag */
u_int16_t ev_bus; /* bus */
u_int16_t ev_event; /* type of async event */
} tmd_event_t;
/*
* Suggested Software Target Mode Command Handling structure.
*
* A note about terminology:
*
* MD stands for "Machine Dependent".
*
* This driver is structured in three layers: Outer MD, core, and inner MD.
* The latter also is bus dependent (i.e., is cognizant of PCI bus issues
* as well as platform issues).
*
*
* "Outer Layer" means "Other Module"
*
* Some additional module that actually implements SCSI target command
* policy is the recipient of incoming commands and the source of the
* disposition for them.
*
* The command structure below is one suggested possible MD command structure,
* but since the handling of thbis is entirely in the MD layer, there is
* no explicit or implicit requirement that it be used.
*
* The cd_private tag should be used by the MD layer to keep a free list
* of these structures. Code outside of this driver can then use this
* as an to identify it's own unit structures. That is, when not on the MD
* layer's freelist, the MD layer should shove into it the identifier
* that the outer layer has for it- passed in on an initial QIN_HBA_REG
* call (see below).
*
* The cd_hba tag is a tag that uniquely identifies the HBA this target
* mode command is coming from. The outer layer has to pass this back
* unchanged to avoid chaos.
*
* The cd_iid, cd_tgt, cd_lun and cd_bus tags are used to identify the
* id of the initiator who sent us a command, the target claim to be, the
* lun on the target we claim to be, and the bus instance (for multiple
* bus host adapters) that this applies to (consider it an extra Port
* parameter). The iid, tgt and lun values are deliberately chosen to be
* fat so that, for example, World Wide Names can be used instead of
* the units that the Qlogic firmware uses (in the case where the MD
* layer maintains a port database, for example).
*
* The cd_tagtype field specifies what kind of command tag has been
* sent with the command. The cd_tagval is the tag's value.
*
* N.B.: when the MD layer sends this command to outside software
* the outside software likely *MUST* return the same cd_tagval that
* was in place because this value is likely what the Qlogic f/w uses
* to identify a command.
*
* The cd_cdb contains storage for the passed in command descriptor block.
* This is the maximum size we can get out of the Qlogic f/w. There's no
* passed in length because whoever decodes the command to act upon it
* will know what the appropriate length is.
*
* The tag cd_lflags are the flags set by the MD driver when it gets
* command incoming or when it needs to inform any outside entities
* that the last requested action failed.
*
* The tag cd_hflags should be set by any outside software to indicate
* the validity of sense and status fields (defined below) and to indicate
* the direction data is expected to move. It is an error to have both
* CDFH_DATA_IN and CDFH_DATA_OUT set.
*
* If the CDFH_STSVALID flag is set, the command should be completed (after
* sending any data and/or status). If CDFH_SNSVALID is set and the MD layer
* can also handle sending the associated sense data (either back with an
* FCP RESPONSE IU for Fibre Channel or otherwise automatically handling a
* REQUEST SENSE from the initator for this target/lun), the MD layer will
* set the CDFL_SENTSENSE flag on successful transmission of the sense data.
* It is an error for the CDFH_SNSVALID bit to be set and CDFH_STSVALID not
* to be set. It is an error for the CDFH_SNSVALID be set and the associated
* SCSI status (cd_scsi_status) not be set to CHECK CONDITON.
*
* The tag cd_data points to a data segment to either be filled or
* read from depending on the direction of data movement. The tag
* is undefined if no data direction is set. The MD layer and outer
* layers must agree on the meaning of cd_data.
*
* The tag cd_totlen is the total data amount expected to be moved
* over the life of the command. It *may* be set by the MD layer, possibly
* from the datalen field of an FCP CMND IU unit. If it shows up in the outer
* layers set to zero and the CDB indicates data should be moved, the outer
* layer should set it to the amount expected to be moved.
*
* The tag cd_resid should be the total residual of data not transferred.
* The outer layers need to set this at the begining of command processing
* to equal cd_totlen. As data is successfully moved, this value is decreased.
* At the end of a command, any nonzero residual indicates the number of bytes
* requested but not moved. XXXXXXXXXXXXXXXXXXXXXXX TOO VAGUE!!!
*
* The tag cd_xfrlen is the length of the currently active data transfer.
* This allows several interations between any outside software and the
* MD layer to move data.
*
* The reason that total length and total residual have to be tracked
* is that fibre channel FCP DATA IU units have to have a relative
* offset field.
*
* N.B.: there is no necessary 1-to-1 correspondence between any one
* data transfer segment and the number of CTIOs that will be generated
* satisfy the current data transfer segment. It's not also possible to
* predict how big a transfer can be before it will be 'too big'. Be
* reasonable- a 64KB transfer is 'reasonable'. A 1MB transfer may not
* be. A 32MB transfer is unreasonable. The problem here has to do with
* how CTIOs can be used to map passed data pointers. In systems which
* have page based scatter-gather requirements, each PAGESIZEd chunk will
* consume one data segment descriptor- you get 3 or 4 of them per CTIO.
* The size of the REQUEST QUEUE you drop a CTIO onto is finite (typically
* it's 256, but on some systems it's even smaller, and note you have to
* sure this queue with the initiator side of this driver).
*
* The tags cd_sense and cd_scsi_status are pretty obvious.
*
* The tag cd_error is to communicate between the MD layer and outer software
* the current error conditions.
*
* The tag cd_reserved pads out the structure to 128 bytes.
*/
#ifndef _LP64
#if defined(__alpha__) || defined(__sparcv9cpu) || defined(__sparc_v9__)
#define _LP64
#endif
#endif
#ifndef _TMD_PAD_LEN
#ifdef _LP64
#define _TMD_PAD_LEN 12
#else
#define _TMD_PAD_LEN 24
#endif
#endif
#ifndef ATIO_CDBLEN
#define ATIO_CDBLEN 26
#endif
#ifndef QLTM_SENSELEN
#define QLTM_SENSELEN 18
#endif
typedef struct tmd_cmd {
void * cd_private; /* layer private data */
void * cd_hba; /* HBA tag */
void * cd_data; /* 'pointer' to data */
u_int64_t cd_iid; /* initiator ID */
u_int64_t cd_tgt; /* target id */
u_int64_t cd_lun; /* logical unit */
u_int8_t cd_bus; /* bus */
u_int8_t cd_tagtype; /* tag type */
u_int16_t cd_tagval; /* tag value */
u_int8_t cd_cdb[ATIO_CDBLEN]; /* Command */
u_int8_t cd_lflags; /* flags lower level sets */
u_int8_t cd_hflags; /* flags higher level sets */
u_int32_t cd_totlen; /* total data requirement */
u_int32_t cd_resid; /* total data residual */
u_int32_t cd_xfrlen; /* current data requirement */
int32_t cd_error; /* current error */
u_int8_t cd_sense[QLTM_SENSELEN];
u_int16_t cd_scsi_status; /* closing SCSI status */
u_int8_t cd_reserved[_TMD_PAD_LEN];
} tmd_cmd_t;
#define CDFL_BUSY 0x01 /* this command is not on a free list */
#define CDFL_NODISC 0x02 /* disconnects disabled */
#define CDFL_SENTSENSE 0x04 /* last action sent sense data */
#define CDFL_SENTSTATUS 0x08 /* last action sent status */
#define CDFL_ERROR 0x10 /* last action ended in error */
#define CDFL_PRIVATE_0 0x80 /* private layer flags */
#define CDFH_SNSVALID 0x01 /* sense data valid */
#define CDFH_STSVALID 0x02 /* status valid */
#define CDFH_NODATA 0x00 /* no data transfer expected */
#define CDFH_DATA_IN 0x04 /* target (us) -> initiator (them) */
#define CDFH_DATA_OUT 0x08 /* initiator (them) -> target (us) */
#define CDFH_DATA_MASK 0x0C /* mask to cover data direction */
#define CDFH_PRIVATE_0 0x80 /* private layer flags */
/*
* Action codes set by the Qlogic MD target driver for
* the external layer to figure out what to do with.
*/
typedef enum {
QOUT_HBA_REG=0, /* the argument is a pointer to a hba_register_t */
QOUT_TMD_START, /* the argument is a pointer to a tmd_cmd_t */
QOUT_TMD_DONE, /* the argument is a pointer to a tmd_cmd_t */
QOUT_TEVENT, /* the argument is a pointer to a tmd_event_t */
QOUT_TMSG, /* the argument is a pointer to a tmd_msg_t */
QOUT_HBA_UNREG /* the argument is a pointer to a hba_register_t */
} tact_e;
/*
* Action codes set by the external layer for the
* MD Qlogic driver to figure out what to do with.
*/
typedef enum {
QIN_HBA_REG=6, /* the argument is a pointer to a hba_register_t */
QIN_ENABLE, /* the argument is a pointer to a tmd_cmd_t */
QIN_DISABLE, /* the argument is a pointer to a tmd_cmd_t */
QIN_TMD_CONT, /* the argument is a pointer to a tmd_cmd_t */
QIN_TMD_FIN, /* the argument is a pointer to a done tmd_cmd_t */
QIN_HBA_UNREG /* the argument is a pointer to a hba_register_t */
} qact_e;
/*
* A word about the START/CONT/DONE/FIN dance:
*
* When the HBA is enabled for receiving commands, one may show up
* without notice. When that happens, the Qlogic target mode driver
* gets a tmd_cmd_t, fills it with the info that just arrived, and
* calls the outer layer with a QIN_TMD_START code and pointer to
* the tmd_cmd_t.
*
* The outer layer decodes the command, fetches data, prepares stuff,
* whatever, and starts by passing back the pointer with a QIN_TMD_CONT
* code which causes the Qlogic target mode driver to generate CTIOs to
* satisfy whatever action needs to be taken. When those CTIOs complete,
* the Qlogic target driver sends the pointer to the cmd_tmd_t back with
* a QOUT_TMD_DONE code. This repeats for as long as necessary.
*
* The outer layer signals it wants to end the command by settings within
* the tmd_cmd_t itself. When the final QIN_TMD_CONT is reported completed,
* the outer layer frees the tmd_cmd_t by sending the pointer to it
* back with a QIN_TMD_FIN code.
*
* The graph looks like:
*
* QOUT_TMD_START -> [ QIN_TMD_CONT -> QOUT_TMD_DONE ] * -> QIN_TMD_FIN.
*
*/
/*
* A word about ENABLE/DISABLE: the argument is a pointer to an tmd_cmd_t
* with cd_hba, cd_bus, cd_tgt and cd_lun filled out. If an error occurs
* in either enabling or disabling the described lun, cd_lflags is set
* with CDFL_ERROR.
*
* Logical unit zero must be the first enabled and the last disabled.
*/
/*
* Target handler functions.
* The MD target handler function (the outer layer calls this)
* should be be prototyped like:
*
* void target_action(qact_e, void *arg)
*
* The outer layer target handler function (the MD layer calls this)
* should be be prototyped like:
*
* void system_action(tact_e, void *arg)
*/
/*
* This structure is used to register to other software modules the
* binding of an HBA identifier, driver name and instance and the
* lun width capapbilities of this target driver. It's up to each
* platform to figure out how it wants to do this, but a typical
* sequence would be for the MD layer to find some external module's
* entry point and start by sending a QOUT_HBA_REG with info filled
* in, and the external module to call back with a QIN_HBA_REG that
* passes back the corresponding information.
*/
typedef struct {
void * r_identity;
char r_name[8];
int r_inst;
int r_lunwidth;
int r_buswidth;
void (*r_action) __P((int, void *));
} hba_register_t;