Subversion Repositories or1k

/* Code to support devices on the DIO (and eventually DIO-II) bus

 * Copyright (C) 05/1998 Peter Maydell <pmaydell@chiark.greenend.org.uk>

 *

 * This code has basically these routines at the moment:

 * int dio_find(u_int deviceid)

 *    Search the list of DIO devices and return the select code

 *    of the next unconfigured device found that matches the given device ID.

 *    Note that the deviceid parameter should be the encoded ID.

 *    This means that framebuffers should pass it as

 *    DIO_ENCODE_ID(DIO_ID_FBUFFER,DIO_ID2_TOPCAT)

 *    (or whatever); everybody else just uses DIO_ID_FOOBAR.

 * void *dio_scodetoviraddr(int scode)

 *    Return the virtual address corresponding to the given select code.

 *    NB: DIO-II devices will have to be mapped in in this routine!

 * int dio_scodetoipl(int scode)

 *    Every DIO card has a fixed interrupt priority level. This function

 *    returns it, whatever it is.

 * const char *dio_scodetoname(int scode)

 *    Return a character string describing this board [might be "" if

 *    not CONFIG_DIO_CONSTANTS]

 * void dio_config_board(int scode)     mark board as configured in the list

 * void dio_unconfig_board(int scode)   mark board as no longer configured

 *

 * This file is based on the way the Amiga port handles Zorro II cards,

 * although we aren't so complicated...

 */

#include <linux/config.h>

#include <linux/kernel.h>

#include <linux/types.h>

#include <linux/dio.h>

#include <linux/slab.h>                         /* kmalloc() */

#include <linux/init.h>

#include <asm/hwtest.h>                           /* hwreg_present() */

#include <asm/io.h>

/* not a real config option yet! */

#define CONFIG_DIO_CONSTANTS

#ifdef CONFIG_DIO_CONSTANTS

/* We associate each numeric ID with an appropriate descriptive string

 * using a constant array of these structs.

 * FIXME: we should be able to arrange to throw away most of the strings

 * using the initdata stuff. Then we wouldn't need to worry about

 * carrying them around...

 * I think we do this by copying them into newly kmalloc()ed memory and

 * marking the names[] array as .initdata ?

 */

struct dioname

{

        int id;

        const char *name;

};

/* useful macro */

#define DIONAME(x) { DIO_ID_##x, DIO_DESC_##x }

#define DIOFBNAME(x) { DIO_ENCODE_ID( DIO_ID_FBUFFER, DIO_ID2_##x), DIO_DESC2_##x }

static struct dioname names[] =

{

        DIONAME(DCA0), DIONAME(DCA0REM), DIONAME(DCA1), DIONAME(DCA1REM),

        DIONAME(DCM), DIONAME(DCMREM),

        DIONAME(LAN),

        DIONAME(FHPIB), DIONAME(NHPIB), DIONAME(IHPIB),

        DIONAME(SCSI0), DIONAME(SCSI1), DIONAME(SCSI2), DIONAME(SCSI3),

        DIONAME(FBUFFER),

        DIONAME(PARALLEL), DIONAME(VME), DIONAME(DCL), DIONAME(DCLREM),

        DIONAME(MISC0), DIONAME(MISC1), DIONAME(MISC2), DIONAME(MISC3),

        DIONAME(MISC4), DIONAME(MISC5), DIONAME(MISC6), DIONAME(MISC7),

        DIONAME(MISC8), DIONAME(MISC9), DIONAME(MISC10), DIONAME(MISC11),

        DIONAME(MISC12), DIONAME(MISC13),

        DIOFBNAME(GATORBOX), DIOFBNAME(TOPCAT), DIOFBNAME(RENAISSANCE),

        DIOFBNAME(LRCATSEYE), DIOFBNAME(HRCCATSEYE), DIOFBNAME(HRMCATSEYE),

        DIOFBNAME(DAVINCI), DIOFBNAME(XXXCATSEYE), DIOFBNAME(HYPERION),

        DIOFBNAME(XGENESIS), DIOFBNAME(TIGER), DIOFBNAME(YGENESIS)

};

#undef DIONAME

#undef DIOFBNAME

#define NUMNAMES (sizeof(names) / sizeof(struct dioname))

static const char *unknowndioname

        = "unknown DIO board -- please email <pmaydell@chiark.greenend.org.uk>!";

static const char *dio_getname(int id)

{

        /* return pointer to a constant string describing the board with given ID */

        unsigned int i;

        for (i = 0; i < NUMNAMES; i++)

                if (names[i].id == id)

                        return names[i].name;

        return unknowndioname;

}

#else

static char dio_no_name[] = { 0 };

#define dio_getname(_id)        (dio_no_name)

#endif /* CONFIG_DIO_CONSTANTS */

/* We represent all the DIO boards in the system with a linked list of these structs. */

struct dioboard

{

        struct dioboard *next;                    /* link to next struct in list */

        int ipl;                                  /* IPL of this board */

        int configured;                           /* has this board been configured? */

        int scode;                                /* select code of this board */

        int id;                                   /* encoded ID */

        const char *name;

};

static struct dioboard *blist = NULL;

static int __init dio_find_slow(int deviceid)

{

        /* Called to find a DIO device before the full bus scan has run.  Basically

         * only used by the console driver.

         * We don't do the primary+secondary ID encoding thing here. Maybe we should.

         * (that would break the topcat detection, though. I need to think about

         * the whole primary/secondary ID thing.)

         */

        int scode;

        u_char prid;

        for (scode = 0; scode < DIO_SCMAX; scode++)

        {

                void *va;

                if (DIO_SCINHOLE(scode))

                        continue;

                va = dio_scodetoviraddr(scode);

                if (!va || !hwreg_present(va + DIO_IDOFF))

                        continue;             /* no board present at that select code */

                /* We aren't very likely to want to use this to get at the IHPIB,

                 * but maybe it's returning the same ID as the card we do want...

                 */

                if (!DIO_ISIHPIB(scode))

                        prid = DIO_ID(va);

                else

                        prid = DIO_ID_IHPIB;

                if (prid == deviceid)

                        return scode;

        }

        return 0;

}

/* Aargh: we use 0 for an error return code, but select code 0 exists!

 * FIXME (trivial, use -1, but requires changes to all the drivers :-< )

 */

int dio_find(int deviceid)

{

        if (blist)

        {

                /* fast way */

                struct dioboard *b;

                for (b = blist; b; b = b->next)

                        if (b->id == deviceid && b->configured == 0)

                                return b->scode;

                return 0;

        }

        return dio_find_slow(deviceid);

}

/* This is the function that scans the DIO space and works out what

 * hardware is actually present.

 */

void __init dio_init(void)

{

        int scode;

        struct dioboard *b, *bprev = NULL;

        printk("Scanning for DIO devices...\n");

        for (scode = 0; scode < DIO_SCMAX; ++scode)

        {

                u_char prid, secid = 0;        /* primary, secondary ID bytes */

                u_char *va;

                if (DIO_SCINHOLE(scode))

                        continue;

                va = dio_scodetoviraddr(scode);

                if (!va || !hwreg_present(va + DIO_IDOFF))

                        continue;              /* no board present at that select code */

                /* Found a board, allocate it an entry in the list */

                b = kmalloc(sizeof(struct dioboard), GFP_KERNEL);

                /* read the ID byte(s) and encode if necessary. Note workaround

                 * for broken internal HPIB devices...

                 */

                if (!DIO_ISIHPIB(scode))

                        prid = DIO_ID(va);

                else

                        prid = DIO_ID_IHPIB;

                if (DIO_NEEDSSECID(prid))

                {

                        secid = DIO_SECID(va);

                        b->id = DIO_ENCODE_ID(prid, secid);

                }

                else

                        b->id = prid;

                b->configured = 0;

                b->scode = scode;

                b->ipl = DIO_IPL(va);

                b->name = dio_getname(b->id);

                printk("select code %3d: ipl %d: ID %02X", scode, b->ipl, prid);

                if (DIO_NEEDSSECID(b->id))

                        printk(":%02X", secid);

                printk(": %s\n", b->name);

                b->next = NULL;

                if (bprev)

                        bprev->next = b;

                else

                        blist = b;

                bprev = b;

        }

}

/* Bear in mind that this is called in the very early stages of initialisation

 * in order to get the virtual address of the serial port for the console...

 */

void *dio_scodetoviraddr(int scode)

{

        if (scode > DIOII_SCBASE)

        {

                printk("dio_scodetoviraddr: don't support DIO-II yet!\n");

                return 0;

        }

        else if (scode > DIO_SCMAX || scode < 0)

                return 0;

        else if (DIO_SCINHOLE(scode))

                return 0;

        else if (DIO_ISIHPIB(scode))

                return (void*)DIO_IHPIBADDR;

        return (void*)(DIO_VIRADDRBASE + DIO_BASE + scode * 0x10000);

}

int dio_scodetoipl(int scode)

{

        struct dioboard *b;

        for (b = blist; b; b = b->next)

                if (b->scode == scode)

                        break;

        if (!b)

        {

                printk("dio_scodetoipl: bad select code %d\n", scode);

                return 0;

        }

        else

                return b->ipl;

}

const char *dio_scodetoname(int scode)

{

        struct dioboard *b;

        for (b = blist; b; b = b->next)

                if (b->scode == scode)

                        break;

        if (!b)

        {

                printk("dio_scodetoname: bad select code %d\n", scode);

                return NULL;

        }

        else

                return b->name;

}

void dio_config_board(int scode)

{

        struct dioboard *b;

        for (b = blist; b; b = b->next)

                if (b->scode == scode)

                        break;

        if (!b)

                printk("dio_config_board: bad select code %d\n", scode);

        else if (b->configured)

                printk("dio_config_board: board at select code %d already configured\n", scode);

        else

                b->configured = 1;

}

void dio_unconfig_board(int scode)

{

        struct dioboard *b;

        for (b = blist; b; b = b->next)

                if (b->scode == scode)

                        break;

        if (!b)

                printk("dio_unconfig_board: bad select code %d\n", scode);

        else if (!b->configured)

                printk("dio_unconfig_board: board at select code %d not configured\n",

                       scode);

        else

                b->configured = 0;

}