sys/h/mbavar.h

/*      mbavar.h        4.15    81/04/08        */

/*
 * This file contains definitions related to the kernel structures
 * for dealing with the massbus adapters.
 *
 * Each mba has a mba_hd structure.
 * Each massbus device has a mba_device structure.
 * Each massbus slave has a mba_slave structure.
 *
 * At boot time we prowl the structures and fill in the pointers
 * for devices which we find.
 */

/*
 * Per-mba structure.
 *
 * The initialization routine uses the information in the mbdinit table
 * to initialize the what is attached to each massbus slot information.
 * It counts the number of devices on each mba (to see if bothering to
 * search/seek is appropriate).
 *
 * During normal operation, the devices attached to the mba which wish
 * to transfer are queued on the mh_act? links.
 */
struct  mba_hd {
        short   mh_active;              /* set if mba is active */
        short   mh_ndrive;              /* number of devices, to avoid seeks */
        struct  mba_regs *mh_mba;       /* virt addr of mba */
        struct  mba_regs *mh_physmba;   /* phys addr of mba */
        struct  mba_device *mh_mbip[8]; /* what is attached to each dev */
        struct  mba_device *mh_actf;    /* head of queue to transfer */
        struct  mba_device *mh_actl;    /* tail of queue to transfer */
};

/*
 * Per-device structure
 * (one for each RM/RP disk, and one for each tape formatter).
 *
 * This structure is used by the device driver as its argument
 * to the massbus driver, and by the massbus driver to locate
 * the device driver for a particular massbus slot.
 *
 * The device drivers hang ready buffers on this structure,
 * and the massbus driver will start i/o on the first such buffer
 * when appropriate.
 */
struct  mba_device {
        struct  mba_driver *mi_driver;
        short   mi_unit;        /* unit number to the system */
        short   mi_mbanum;      /* the mba it is on */
        short   mi_drive;       /* controller on mba */
        short   mi_dk;          /* driver number for iostat */
        short   mi_alive;       /* device exists */
        short   mi_type;        /* driver specific unit type */
        struct  buf mi_tab;     /* head of queue for this device */
        struct  mba_device *mi_forw;
/* we could compute these every time, but hereby save time */
        struct  mba_regs *mi_mba;
        struct  mba_drv *mi_drv;
        struct  mba_hd *mi_hd;
};

/*
 * Tape formatter slaves are specified by
 * the following information which is used
 * at boot time to initialize the tape driver
 * internal tables.
 */
struct  mba_slave {
        struct  mba_driver *ms_driver;
        short   ms_ctlr;                /* which of several formatters */
        short   ms_unit;                /* which unit to system */
        short   ms_slave;               /* which slave to formatter */
        short   ms_alive;
};

/*
 * Per device-type structure.
 *
 * Each massbus driver defines entries for a set of routines used
 * by the massbus driver, as well as an array of types which are
 * acceptable to it.
 */
struct mba_driver {
        int     (*md_attach)();         /* attach a device */
        int     (*md_slave)();          /* attach a slave */
        int     (*md_ustart)();         /* unit start routine */
        int     (*md_start)();          /* setup a data transfer */
        int     (*md_dtint)();          /* data transfer complete */
        int     (*md_ndint)();          /* non-data transfer interrupt */
        short   *md_type;               /* array of drive type codes */
        char    *md_dname, *md_sname;   /* device, slave names */
        struct  mba_device **md_info;   /* backpointers to mbinit structs */
};

/*
 * Possible return values from unit start routines.
 */
#define MBU_NEXT        0               /* skip to next operation */
#define MBU_BUSY        1               /* dual port busy; wait for intr */
#define MBU_STARTED     2               /* non-data transfer started */
#define MBU_DODATA      3               /* data transfer ready; start mba */

/*
 * Possible return values from data transfer interrupt handling routines
 */
#define MBD_DONE        0               /* data transfer complete */
#define MBD_RETRY       1               /* error occurred, please retry */
#define MBD_RESTARTED   2               /* driver restarted i/o itself */

/*
 * Possible return values from non-data-transfer interrupt handling routines
 */
#define MBN_DONE        0               /* non-data transfer complete */
#define MBN_RETRY       1               /* failed; retry the operation */
#define MBN_SKIP        2               /* don't do anything */

/*
 * Clear attention status for specified device.
 */
#define mbclrattn(mi)   ((mi)->mi_mba->mba_drv[0].mbd_as = 1 << (mi)->mi_drive)

/*
 * Kernel definitions related to mba.
 */
#ifdef KERNEL
int     nummba;
#if NMBA > 0
struct  mba_hd mba_hd[NMBA];
extern  Xmba0int(), Xmba1int(), Xmba2int(), Xmba3int();

extern  struct  mba_device mbdinit[];
extern  struct  mba_slave mbsinit[];
#endif
#endif