root/sys/dev/ic/bt485.c
/* $OpenBSD: bt485.c,v 1.16 2025/06/28 16:04:10 miod Exp $ */
/* $NetBSD: bt485.c,v 1.2 2000/04/02 18:55:01 nathanw Exp $ */

/*
 * Copyright (c) 1995, 1996 Carnegie-Mellon University.
 * All rights reserved.
 *
 * Author: Chris G. Demetriou
 *
 * Permission to use, copy, modify and distribute this software and
 * its documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 *
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 *
 * Carnegie Mellon requests users of this software to return to
 *
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 *
 * any improvements or extensions that they make and grant Carnegie the
 * rights to redistribute these changes.
 */

 /* This code was derived from and originally located in sys/dev/pci/
  *      NetBSD: tga_bt485.c,v 1.4 1999/03/24 05:51:21 mrg Exp 
  */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/buf.h>
#include <sys/kernel.h>
#include <sys/malloc.h>

#include <dev/pci/pcivar.h>
#include <dev/ic/bt485reg.h>
#include <dev/ic/bt485var.h>
#include <dev/ic/ramdac.h>

#include <dev/wscons/wsconsio.h>
#include <dev/wscons/wsdisplayvar.h>
#include <dev/rasops/rasops.h>

/*
 * Functions exported via the RAMDAC configuration table.
 */
void    bt485_init(struct ramdac_cookie *);
int     bt485_set_cmap(struct ramdac_cookie *,
            struct wsdisplay_cmap *);
int     bt485_get_cmap(struct ramdac_cookie *,
            struct wsdisplay_cmap *);
int     bt485_set_cursor(struct ramdac_cookie *,
            struct wsdisplay_cursor *);
int     bt485_get_cursor(struct ramdac_cookie *,
            struct wsdisplay_cursor *);
int     bt485_set_curpos(struct ramdac_cookie *,
            struct wsdisplay_curpos *);
int     bt485_get_curpos(struct ramdac_cookie *,
            struct wsdisplay_curpos *);
int     bt485_get_curmax(struct ramdac_cookie *,
            struct wsdisplay_curpos *);

/* XXX const */
struct ramdac_funcs bt485_funcsstruct = {
        "Bt485",
        bt485_register,
        bt485_init,
        bt485_set_cmap,
        bt485_get_cmap,
        bt485_set_cursor,
        bt485_get_cursor,
        bt485_set_curpos,
        bt485_get_curpos,
        bt485_get_curmax,
        NULL,                   /* check_curcmap; not needed */
        NULL,                   /* set_curcmap; not needed */
        NULL,                   /* get_curcmap; not needed */
        NULL,                   /* no dot clock to set */
};

/*
 * Private data.
 */
struct bt485data {
        void            *cookie;        /* This is what is passed
                                         * around, and is probably
                                         * struct tga_devconfig *
                                         */
        
        int             (*ramdac_sched_update)(void *, void (*)(void *));
        void            (*ramdac_wr)(void *, u_int, u_int8_t);
        u_int8_t        (*ramdac_rd)(void *, u_int);

        int     changed;                        /* what changed; see below */
        int     curenb;                         /* cursor enabled */
        struct wsdisplay_curpos curpos;         /* current cursor position */
        struct wsdisplay_curpos curhot;         /* cursor hotspot */
        char curcmap_r[2];                      /* cursor colormap */
        char curcmap_g[2];
        char curcmap_b[2];
        struct wsdisplay_curpos cursize;        /* current cursor size */
        char curimage[512];                     /* cursor image data */
        char curmask[512];                      /* cursor mask data */
        char cmap_r[256];                               /* colormap */
        char cmap_g[256];
        char cmap_b[256];
};

#define DATA_ENB_CHANGED        0x01    /* cursor enable changed */
#define DATA_CURCMAP_CHANGED    0x02    /* cursor colormap changed */
#define DATA_CURSHAPE_CHANGED   0x04    /* cursor size, image, mask changed */
#define DATA_CMAP_CHANGED       0x08    /* colormap changed */
#define DATA_ALL_CHANGED        0x0f

#define CURSOR_MAX_SIZE         64

/*
 * Internal functions.
 */
inline void     bt485_wr_i(struct bt485data *, u_int8_t, u_int8_t);
inline u_int8_t bt485_rd_i(struct bt485data *, u_int8_t);
void    bt485_update(void *);
void    bt485_update_curpos(struct bt485data *);

/*****************************************************************************/

/*
 * Functions exported via the RAMDAC configuration table.
 */

struct ramdac_funcs *
bt485_funcs(void)
{
        return &bt485_funcsstruct;
}

struct ramdac_cookie *
bt485_register(void *v, int (*sched_update)(void *, void (*)(void *)),
    void (*wr)(void *, u_int, u_int8_t), u_int8_t (*rd)(void *, u_int))
{
        struct bt485data *data;
        /*
         * XXX -- comment out of date.  rcd.
         * If we should allocate a new private info struct, do so.
         * Otherwise, use the one we have (if it's there), or
         * use the temporary one on the stack.
         */
        data = malloc(sizeof *data, M_DEVBUF, M_WAITOK);
        /* XXX -- if !data */
        data->cookie = v;
        data->ramdac_sched_update = sched_update;
        data->ramdac_wr = wr;
        data->ramdac_rd = rd;
        return (struct ramdac_cookie *)data;
}

/*
 * This function exists solely to provide a means to init
 * the RAMDAC without first registering.  It is useful for
 * initializing the console early on.
 */
void
bt485_cninit(void *v, int (*sched_update)(void *, void (*)(void *)),
    void (*wr)(void *, u_int, u_int8_t), u_int8_t (*rd)(void *, u_int))
{
        struct bt485data tmp, *data = &tmp;
        data->cookie = v;
        data->ramdac_sched_update = sched_update;
        data->ramdac_wr = wr;
        data->ramdac_rd = rd;
        bt485_init((struct ramdac_cookie *)data);
}

void
bt485_init(struct ramdac_cookie *rc)
{
        u_int8_t regval;
        struct bt485data *data = (struct bt485data *)rc;
        int i;

        /*
         * Init the BT485 for normal operation.
         */

        /*
         * Allow indirect register access.  (Actually, this is
         * already enabled.  In fact, if it is _disabled_, for
         * some reason the monitor appears to lose sync!!! (?!?!)
         */
        regval = data->ramdac_rd(data->cookie, BT485_REG_COMMAND_0);
        regval |= 0x80;
        /*
         * Set the RAMDAC to 8 bit resolution, rather than 6 bit
         * resolution.
         */
        regval |= 0x02;
        data->ramdac_wr(data->cookie, BT485_REG_COMMAND_0, regval);

        /* Set the RAMDAC to 8BPP (no interesting options). */
        data->ramdac_wr(data->cookie, BT485_REG_COMMAND_1, 0x40);

        /* Disable the cursor (for now) */
        regval = data->ramdac_rd(data->cookie, BT485_REG_COMMAND_2);
        regval &= ~0x03;
        regval |= 0x24;
        data->ramdac_wr(data->cookie, BT485_REG_COMMAND_2, regval);

        /* Use a 64x64x2 cursor */
        regval = bt485_rd_i(data, BT485_IREG_COMMAND_3);
        regval |= 0x04;
        regval |= 0x08;
        bt485_wr_i(data, BT485_IREG_COMMAND_3, regval);

        /* Set the Pixel Mask to something useful */
        data->ramdac_wr(data->cookie, BT485_REG_PIXMASK, 0xff);

        /*
         * Initialize the RAMDAC info struct to hold all of our
         * data, and fill it in.
         */
        data->changed = DATA_ALL_CHANGED;

        data->curenb = 0;                               /* cursor disabled */
        data->curpos.x = data->curpos.y = 0;            /* right now at 0,0 */
        data->curhot.x = data->curhot.y = 0;            /* hot spot at 0,0 */

        /* initial cursor colormap: 0 is black, 1 is white */
        data->curcmap_r[0] = data->curcmap_g[0] = data->curcmap_b[0] = 0;
        data->curcmap_r[1] = data->curcmap_g[1] = data->curcmap_b[1] = 0xff;

        /* initial cursor data: 64x64 block of white. */
        data->cursize.x = data->cursize.y = 64;
        for (i = 0; i < 512; i++)
                data->curimage[i] = data->curmask[i] = 0xff;

        /* Initial colormap: 0 is black, everything else is white */
        data->cmap_r[0] = data->cmap_g[0] = data->cmap_b[0] = 0;
        for (i = 0; i < 256; i++) {
                data->cmap_r[i] = rasops_cmap[3*i + 0];
                data->cmap_g[i] = rasops_cmap[3*i + 1];
                data->cmap_b[i] = rasops_cmap[3*i + 2];
        }

        bt485_update((void *)data);
}

int
bt485_set_cmap(struct ramdac_cookie *rc, struct wsdisplay_cmap *cmapp)
{
        struct bt485data *data = (struct bt485data *)rc;
        u_int count, index;
        int s, error;

#ifdef DIAGNOSTIC
        if (rc == NULL)
                panic("bt485_set_cmap: rc");
        if (cmapp == NULL)
                panic("bt485_set_cmap: cmapp");
#endif
        index = cmapp->index;
        count = cmapp->count;

        if (index >= 256 || count > 256 - index)
                return (EINVAL);

        s = spltty();

        if ((error = copyin(cmapp->red, &data->cmap_r[index], count)) != 0) {
                splx(s);
                return (error);
        }
        if ((error = copyin(cmapp->green, &data->cmap_g[index], count)) != 0) {
                splx(s);
                return (error);
        }
        if ((error = copyin(cmapp->blue, &data->cmap_b[index], count)) != 0) {
                splx(s);
                return (error);
        }

        data->changed |= DATA_CMAP_CHANGED;

        data->ramdac_sched_update(data->cookie, bt485_update);
#ifdef __alpha__
        alpha_mb();
#endif
        splx(s);

        return (0);
}

int
bt485_get_cmap(struct ramdac_cookie *rc, struct wsdisplay_cmap *cmapp)
{
        struct bt485data *data = (struct bt485data *)rc;
        u_int count, index;
        int error;

        if (cmapp->index >= 256 || cmapp->count > 256 - cmapp->index)
                return (EINVAL);

        count = cmapp->count;
        index = cmapp->index;

        error = copyout(&data->cmap_r[index], cmapp->red, count);
        if (error)
                return (error);
        error = copyout(&data->cmap_g[index], cmapp->green, count);
        if (error)
                return (error);
        error = copyout(&data->cmap_b[index], cmapp->blue, count);
        return (error);
}

int
bt485_set_cursor(struct ramdac_cookie *rc, struct wsdisplay_cursor *cursorp)
{
        struct bt485data *data = (struct bt485data *)rc;
        u_int count, index;
        int error;
        int v, s;

        v = cursorp->which;

        /*
         * For DOCMAP and DOSHAPE, verify that parameters are OK
         * before we do anything that we can't recover from.
         */
        if (v & WSDISPLAY_CURSOR_DOCMAP) {
                index = cursorp->cmap.index;
                count = cursorp->cmap.count;
                if (index >= 2 || count > 2 - index)
                        return (EINVAL);
        }
        if (v & WSDISPLAY_CURSOR_DOSHAPE) {
                if ((u_int)cursorp->size.x > CURSOR_MAX_SIZE ||
                    (u_int)cursorp->size.y > CURSOR_MAX_SIZE)
                        return (EINVAL);
        }

        if (v & (WSDISPLAY_CURSOR_DOPOS | WSDISPLAY_CURSOR_DOCUR)) {
                if (v & WSDISPLAY_CURSOR_DOPOS)
                        data->curpos = cursorp->pos;
                if (v & WSDISPLAY_CURSOR_DOCUR)
                        data->curhot = cursorp->hot;
                bt485_update_curpos(data);
        }

        s = spltty();

        /* Parameters are OK; perform the requested operations. */
        if (v & WSDISPLAY_CURSOR_DOCUR) {
                data->curenb = cursorp->enable;
                data->changed |= DATA_ENB_CHANGED;
        }
        if (v & WSDISPLAY_CURSOR_DOCMAP) {
                index = cursorp->cmap.index;
                count = cursorp->cmap.count;
                if ((error = copyin(cursorp->cmap.red,
                    &data->curcmap_r[index], count)) != 0) {
                        splx(s);
                        return (error);
                }
                if ((error = copyin(cursorp->cmap.green,
                    &data->curcmap_g[index], count)) != 0) {
                        splx(s);
                        return (error);
                }
                if ((error = copyin(cursorp->cmap.blue,
                    &data->curcmap_b[index], count)) != 0) {
                        splx(s);
                        return (error);
                }
                data->changed |= DATA_CURCMAP_CHANGED;
        }
        if (v & WSDISPLAY_CURSOR_DOSHAPE) {
                data->cursize = cursorp->size;
                count = (CURSOR_MAX_SIZE / NBBY) * data->cursize.y;
                bzero(data->curimage, sizeof data->curimage);
                bzero(data->curmask, sizeof data->curmask);
                if ((error = copyin(cursorp->image, data->curimage,
                    count)) != 0) {
                        splx(s);
                        return (error);
                }
                if ((error = copyin(cursorp->mask, data->curmask,
                    count)) != 0) {
                        splx(s);
                        return (error);
                }
                data->changed |= DATA_CURSHAPE_CHANGED;
        }

        if (data->changed)
                data->ramdac_sched_update(data->cookie, bt485_update);
        splx(s);

        return (0);
}

int
bt485_get_cursor(struct ramdac_cookie *rc, struct wsdisplay_cursor *cursorp)
{
        struct bt485data *data = (struct bt485data *)rc;
        int error, count;

        /* we return everything they want */
        cursorp->which = WSDISPLAY_CURSOR_DOALL;

        cursorp->enable = data->curenb; /* DOCUR */
        cursorp->pos = data->curpos;    /* DOPOS */
        cursorp->hot = data->curhot;    /* DOHOT */

        cursorp->cmap.index = 0;        /* DOCMAP */
        cursorp->cmap.count = 2;
        if (cursorp->cmap.red != NULL) {
                error = copyout(data->curcmap_r, cursorp->cmap.red, 2);
                if (error)
                        return (error);
        }
        if (cursorp->cmap.green != NULL) {
                error = copyout(data->curcmap_g, cursorp->cmap.green, 2);
                if (error)
                        return (error);
        }
        if (cursorp->cmap.blue != NULL) {
                error = copyout(data->curcmap_b, cursorp->cmap.blue, 2);
                if (error)
                        return (error);
        }

        cursorp->size = data->cursize;  /* DOSHAPE */
        if (cursorp->image != NULL) {
                count = (CURSOR_MAX_SIZE / NBBY) * data->cursize.y;
                error = copyout(data->curimage, cursorp->image, count);
                if (error)
                        return (error);
                error = copyout(data->curmask, cursorp->mask, count);
                if (error)
                        return (error);
        }

        return (0);
}

int
bt485_set_curpos(struct ramdac_cookie *rc, struct wsdisplay_curpos *curposp)
{
        struct bt485data *data = (struct bt485data *)rc;

        data->curpos = *curposp;
        bt485_update_curpos(data);

        return (0);
}

int
bt485_get_curpos(struct ramdac_cookie *rc, struct wsdisplay_curpos *curposp)
{
        struct bt485data *data = (struct bt485data *)rc;

        *curposp = data->curpos;
        return (0);
}

int
bt485_get_curmax(struct ramdac_cookie *rc, struct wsdisplay_curpos *curposp)
{

        curposp->x = curposp->y = CURSOR_MAX_SIZE;
        return (0);
}

/*****************************************************************************/

/*
 * Internal functions.
 */

inline void
bt485_wr_i(struct bt485data *data, u_int8_t ireg, u_int8_t val)
{
        data->ramdac_wr(data->cookie, BT485_REG_PCRAM_WRADDR, ireg);
        data->ramdac_wr(data->cookie, BT485_REG_EXTENDED, val);
}

inline u_int8_t
bt485_rd_i(struct bt485data *data, u_int8_t ireg)
{
        data->ramdac_wr(data->cookie, BT485_REG_PCRAM_WRADDR, ireg);
        return (data->ramdac_rd(data->cookie, BT485_REG_EXTENDED));
}

void
bt485_update(void *vp)
{
        struct bt485data *data = vp;
        u_int8_t regval;
        int count, i, v;

        v = data->changed;
        data->changed = 0;

        if (v & DATA_ENB_CHANGED) {
                regval = data->ramdac_rd(data->cookie, BT485_REG_COMMAND_2);
                if (data->curenb)
                        regval |= 0x01;
                else
                        regval &= ~0x03;
                data->ramdac_wr(data->cookie, BT485_REG_COMMAND_2, regval);
        }

        if (v & DATA_CURCMAP_CHANGED) {
                /* addr[9:0] assumed to be 0 */
                /* set addr[7:0] to 1 */
                data->ramdac_wr(data->cookie, BT485_REG_COC_WRADDR, 0x01);

                /* spit out the cursor data */
                for (i = 0; i < 2; i++) {
                        data->ramdac_wr(data->cookie, BT485_REG_COCDATA,
                            data->curcmap_r[i]);
                        data->ramdac_wr(data->cookie, BT485_REG_COCDATA,
                            data->curcmap_g[i]);
                        data->ramdac_wr(data->cookie, BT485_REG_COCDATA,
                            data->curcmap_b[i]);
                }
        }

        if (v & DATA_CURSHAPE_CHANGED) {
                count = (CURSOR_MAX_SIZE / NBBY) * data->cursize.y;

                /*
                 * Write the cursor image data:
                 *      set addr[9:8] to 0,
                 *      set addr[7:0] to 0,
                 *      spit it all out.
                 */
                regval = bt485_rd_i(data, BT485_IREG_COMMAND_3);
                regval &= ~0x03;
                bt485_wr_i(data, BT485_IREG_COMMAND_3, regval);
                data->ramdac_wr(data->cookie, BT485_REG_PCRAM_WRADDR, 0);
                for (i = 0; i < count; i++)
                        data->ramdac_wr(data->cookie, BT485_REG_CURSOR_RAM,
                            data->curimage[i]);
                
                /*
                 * Write the cursor mask data:
                 *      set addr[9:8] to 2,
                 *      set addr[7:0] to 0,
                 *      spit it all out.
                 */
                regval = bt485_rd_i(data, BT485_IREG_COMMAND_3);
                regval &= ~0x03; regval |= 0x02;
                bt485_wr_i(data, BT485_IREG_COMMAND_3, regval);
                data->ramdac_wr(data->cookie, BT485_REG_PCRAM_WRADDR, 0);
                for (i = 0; i < count; i++)
                        data->ramdac_wr(data->cookie, BT485_REG_CURSOR_RAM,
                            data->curmask[i]);

                /* set addr[9:0] back to 0 */
                regval = bt485_rd_i(data, BT485_IREG_COMMAND_3);
                regval &= ~0x03;
                bt485_wr_i(data, BT485_IREG_COMMAND_3, regval);
        }

        if (v & DATA_CMAP_CHANGED) {
                /* addr[9:0] assumed to be 0 */
                /* set addr[7:0] to 0 */
                data->ramdac_wr(data->cookie, BT485_REG_PCRAM_WRADDR, 0x00);

                /* spit out the cursor data */
                for (i = 0; i < 256; i++) {
                        data->ramdac_wr(data->cookie, BT485_REG_PALETTE,
                            data->cmap_r[i]);
                        data->ramdac_wr(data->cookie, BT485_REG_PALETTE,
                            data->cmap_g[i]);
                        data->ramdac_wr(data->cookie, BT485_REG_PALETTE,
                            data->cmap_b[i]);
                }
        }
}

void
bt485_update_curpos(struct bt485data *data)
{
        void *cookie = data->cookie;
        int s, x, y;

        s = spltty();

        x = data->curpos.x + CURSOR_MAX_SIZE - data->curhot.x;
        y = data->curpos.y + CURSOR_MAX_SIZE - data->curhot.y;
        data->ramdac_wr(cookie, BT485_REG_CURSOR_X_LOW, x & 0xff);
        data->ramdac_wr(cookie, BT485_REG_CURSOR_X_HIGH, (x >> 8) & 0x0f);
        data->ramdac_wr(cookie, BT485_REG_CURSOR_Y_LOW, y & 0xff);
        data->ramdac_wr(cookie, BT485_REG_CURSOR_Y_HIGH, (y >> 8) & 0x0f);

        splx(s);
}