/* $OpenBSD: lunafb.c,v 1.32 2023/08/05 00:34:19 aoyama Exp $ */
/* $NetBSD: lunafb.c,v 1.7.6.1 2002/08/07 01:48:34 lukem Exp $ */

/*-
 * Copyright (c) 2000 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Tohru Nishimura.
 *
 * 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.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/device.h>
#include <sys/ioctl.h>
#include <sys/malloc.h>
#include <sys/mman.h>
#include <sys/proc.h>
#include <sys/tty.h>
#include <sys/errno.h>
#include <sys/buf.h>

#include <uvm/uvm_extern.h>

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

#include <machine/autoconf.h>
#include <machine/board.h>
#include <machine/cpu.h>

struct bt454 {
        volatile u_int8_t bt_addr;      /* map address register */
        volatile u_int8_t bt_cmap;      /* colormap data register */
};

struct bt458 {
        volatile u_int8_t bt_addr;      /* map address register */
        unsigned :24;
        volatile u_int8_t bt_cmap;      /* colormap data register */
        unsigned :24;
        volatile u_int8_t bt_ctrl;      /* control register */
        unsigned :24;
        volatile u_int8_t bt_omap;      /* overlay (cursor) map register */
        unsigned :24;
};

#define OMFB_RFCNT      BMAP_RFCNT      /* video h-origin/v-origin */
#define OMFB_PLANEMASK  BMAP_BMSEL      /* planemask register */
#define OMFB_FB_WADDR   (BMAP_BMP + 8)  /* common plane */
#define OMFB_FB_RADDR   (BMAP_BMAP0 + 8)/* plane #0 */
#define OMFB_FB_PLANESIZE  0x40000      /* size of 1 plane, 2048 / 8 * 1024 */
#define OMFB_ROPFUNC    BMAP_FN         /* ROP function code */
#define OMFB_RAMDAC     BMAP_PALLET2    /* Bt454/Bt458 RAMDAC */
#define OMFB_SIZE       (BMAP_FN0 - BMAP_BMP + PAGE_SIZE)

struct hwcmap {
#define CMAP_SIZE 256
        u_int8_t r[CMAP_SIZE];
        u_int8_t g[CMAP_SIZE];
        u_int8_t b[CMAP_SIZE];
};

struct om_hwdevconfig {
        int     dc_wid;                 /* width of frame buffer */
        int     dc_ht;                  /* height of frame buffer */
        int     dc_depth;               /* depth, bits per pixel */
        int     dc_rowbytes;            /* bytes in a FB scan line */
        int     dc_depth_checked;       /* depth is really checked or not */
        int     dc_cmsize;              /* colormap size */
        struct hwcmap dc_cmap;          /* software copy of colormap */
        vaddr_t dc_videobase;           /* base of flat frame buffer */
        struct rasops_info dc_ri;       /* raster blitter variables */
};

struct omfb_softc {
        struct device sc_dev;           /* base device */
        struct om_hwdevconfig *sc_dc;   /* device configuration */
        int nscreens;
};

int  omgetcmap(struct omfb_softc *, struct wsdisplay_cmap *);
int  omsetcmap(struct omfb_softc *, struct wsdisplay_cmap *);

struct om_hwdevconfig omfb_console_dc;
void omfb_getdevconfig(paddr_t, struct om_hwdevconfig *);

/* in omrasops.c */
int     om_copycols(void *, int, int, int, int);
int     om_copyrows(void *, int, int, int num);
int     om_erasecols(void *, int, int, int, uint32_t);
int     om_eraserows(void *, int, int, uint32_t);
void    setup_omrasops1(struct rasops_info *);
void    setup_omrasops4(struct rasops_info *);

struct wsscreen_descr omfb_stdscreen = {
        "std"
};

const struct wsscreen_descr *_omfb_scrlist[] = {
        &omfb_stdscreen,
};

const struct wsscreen_list omfb_screenlist = {
        sizeof(_omfb_scrlist) / sizeof(struct wsscreen_descr *), _omfb_scrlist
};

int     omfbioctl(void *, u_long, caddr_t, int, struct proc *);
paddr_t omfbmmap(void *, off_t, int);
int     omfb_alloc_screen(void *, const struct wsscreen_descr *,
            void **, int *, int *, uint32_t *);
void    omfb_free_screen(void *, void *);
int     omfb_show_screen(void *, void *, int, void (*) (void *, int, int),
            void *);
int     omfb_load_font(void *, void *, struct wsdisplay_font *);
int     omfb_list_font(void *, struct wsdisplay_font *);
int     omfb_set_gfxmode(struct omfb_softc *, struct wsdisplay_gfx_mode *);

void    omfb_set_default_cmap(struct om_hwdevconfig *);
void    omfb_clear_framebuffer(struct om_hwdevconfig *);

const struct wsdisplay_accessops omfb_accessops = {
        .ioctl = omfbioctl,
        .mmap = omfbmmap,
        .alloc_screen = omfb_alloc_screen,
        .free_screen = omfb_free_screen,
        .show_screen = omfb_show_screen,
        .load_font = omfb_load_font,
        .list_font = omfb_list_font
};

int  omfbmatch(struct device *, void *, void *);
void omfbattach(struct device *, struct device *, void *);

const struct cfattach fb_ca = {
        sizeof(struct omfb_softc), omfbmatch, omfbattach
};

struct cfdriver fb_cd = {
        NULL, "fb", DV_DULL
};

/* hardware plane bits; retrieved at boot, will be updated */
extern int hwplanebits;

int omfb_console;
int omfb_cnattach(void);

int
omfbmatch(struct device *parent, void *cf, void *aux)
{
        struct mainbus_attach_args *ma = aux;

        if (strcmp(ma->ma_name, fb_cd.cd_name))
                return (0);
#if 0   /* XXX badaddr() bombs if no framebuffer is installed */
        if (badaddr((caddr_t)ma->ma_addr, 4))
                return (0);
#else
        if (hwplanebits == 0)
                return (0);
#endif
        return (1);
}

void
omfbattach(struct device *parent, struct device *self, void *args)
{
        struct omfb_softc *sc = (struct omfb_softc *)self;
        struct wsemuldisplaydev_attach_args waa;

        if (omfb_console) {
                sc->sc_dc = &omfb_console_dc;
                sc->nscreens = 1;
        } else {
                sc->sc_dc = (struct om_hwdevconfig *)
                    malloc(sizeof(struct om_hwdevconfig), M_DEVBUF,
                        M_WAITOK | M_ZERO);
                omfb_getdevconfig(OMFB_FB_WADDR, sc->sc_dc);
        }
        printf(": %dx%d, %dbpp\n", sc->sc_dc->dc_wid, sc->sc_dc->dc_ht,
            hwplanebits);

        waa.console = omfb_console;
        waa.scrdata = &omfb_screenlist;
        waa.accessops = &omfb_accessops;
        waa.accesscookie = sc;
        waa.defaultscreens = 0;

        config_found(self, &waa, wsemuldisplaydevprint);
}

/* EXPORT */ int
omfb_cnattach(void)
{
        struct om_hwdevconfig *dc = &omfb_console_dc;
        struct rasops_info *ri = &dc->dc_ri;
        uint32_t defattr;

        omfb_getdevconfig(OMFB_FB_WADDR, dc);
        ri->ri_ops.pack_attr(ri, 0, 0, 0, &defattr);
        wsdisplay_cnattach(&omfb_stdscreen, ri, 0, 0, defattr);
        omfb_console = 1;
        return (0);
}

int
omfbioctl(void *v, u_long cmd, caddr_t data, int flag, struct proc *p)
{
        struct omfb_softc *sc = v;
        struct om_hwdevconfig *dc = sc->sc_dc;

        switch (cmd) {
        case WSDISPLAYIO_GTYPE:
                *(u_int *)data = WSDISPLAY_TYPE_LUNA;
                break;

        case WSDISPLAYIO_GINFO:
#define wsd_fbip ((struct wsdisplay_fbinfo *)data)
                wsd_fbip->height = dc->dc_ht;
                wsd_fbip->width = dc->dc_wid;
                wsd_fbip->depth = dc->dc_depth;
                wsd_fbip->stride = dc->dc_rowbytes;
                wsd_fbip->offset = 8;
                wsd_fbip->cmsize = dc->dc_cmsize;
#undef wsd_fbip
                break;

        case WSDISPLAYIO_LINEBYTES:
                *(u_int *)data = dc->dc_rowbytes;
                break;

        case WSDISPLAYIO_GETCMAP:
                return omgetcmap(sc, (struct wsdisplay_cmap *)data);

        case WSDISPLAYIO_PUTCMAP:
                return omsetcmap(sc, (struct wsdisplay_cmap *)data);

        case WSDISPLAYIO_GETSUPPORTEDDEPTH:
                if (dc->dc_depth == 8)
                        *(u_int *)data =
                            WSDISPLAYIO_DEPTH_8 | WSDISPLAYIO_DEPTH_1;
                else
                        *(u_int *)data = WSDISPLAYIO_DEPTH_1;
                break;

        case WSDISPLAYIO_SETGFXMODE:
                return omfb_set_gfxmode(sc, (struct wsdisplay_gfx_mode *)data);

        case WSDISPLAYIO_SVIDEO:
        case WSDISPLAYIO_GVIDEO:
                break;

        case WSDISPLAYIO_GCURPOS:
        case WSDISPLAYIO_SCURPOS:
        case WSDISPLAYIO_GCURMAX:
        case WSDISPLAYIO_GCURSOR:
        case WSDISPLAYIO_SCURSOR:
        default:
                return (-1);
        }

        return (0);
}

/*
 * Return the address that would map the given device at the given
 * offset, allowing for the given protection, or return -1 for error.
 */

paddr_t
omfbmmap(void *v, off_t offset, int prot)
{
        struct omfb_softc *sc = v;
        struct om_hwdevconfig *dc = sc->sc_dc;
        paddr_t cookie = -1;

        if ((offset & PAGE_MASK) != 0)
                return (-1);

#if 0   /* Workaround for making Xorg mono server work */
        if (offset >= 0 && offset < OMFB_SIZE)
                cookie = (paddr_t)(trunc_page(dc->dc_videobase) + offset);
#else
        if (offset >= 0 &&
            offset < dc->dc_rowbytes * dc->dc_ht * hwplanebits + PAGE_SIZE)
                cookie = (paddr_t)(trunc_page(OMFB_FB_RADDR) + offset);
#endif
        return cookie;
}

int
omgetcmap(struct omfb_softc *sc, struct wsdisplay_cmap *p)
{
        u_int index = p->index, count = p->count;
        unsigned int cmsize;
        int error;

        cmsize = sc->sc_dc->dc_cmsize;

        /* Don't touch colormap when we use 1bpp */
        if (cmsize == 0)
                return (0);

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

        error = copyout(&sc->sc_dc->dc_cmap.r[index], p->red, count);
        if (error != 0)
                return (error);
        error = copyout(&sc->sc_dc->dc_cmap.g[index], p->green, count);
        if (error != 0)
                return (error);
        error = copyout(&sc->sc_dc->dc_cmap.b[index], p->blue, count);
        if (error != 0)
                return (error);

        return (0);
}

int
omsetcmap(struct omfb_softc *sc, struct wsdisplay_cmap *p)
{
        struct hwcmap cmap;
        u_int index = p->index, count = p->count;
        unsigned int cmsize, i;
        int error;

        cmsize = sc->sc_dc->dc_cmsize;

        /* Don't touch colormap when we use 1bpp */
        if (cmsize == 0)
                return (0);

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

        error = copyin(p->red, &cmap.r[index], count);
        if (error != 0)
                return (error);
        error = copyin(p->green, &cmap.g[index], count);
        if (error != 0)
                return (error);
        error = copyin(p->blue, &cmap.b[index], count);
        if (error != 0)
                return (error);

        memcpy(&sc->sc_dc->dc_cmap.r[index], &cmap.r[index], count);
        memcpy(&sc->sc_dc->dc_cmap.g[index], &cmap.g[index], count);
        memcpy(&sc->sc_dc->dc_cmap.b[index], &cmap.b[index], count);

        if (hwplanebits == 4) {
                struct bt454 *odac = (struct bt454 *)OMFB_RAMDAC;
                odac->bt_addr = (u_int8_t)index;
                for (i = index; i < index + count; i++) {
                        odac->bt_cmap = sc->sc_dc->dc_cmap.r[i];
                        odac->bt_cmap = sc->sc_dc->dc_cmap.g[i];
                        odac->bt_cmap = sc->sc_dc->dc_cmap.b[i];
                }
        }
        else if (hwplanebits == 8) {
                struct bt458 *ndac = (struct bt458 *)OMFB_RAMDAC;
                ndac->bt_addr = (u_int8_t)index;
                for (i = index; i < index + count; i++) {
                        ndac->bt_cmap = sc->sc_dc->dc_cmap.r[i];
                        ndac->bt_cmap = sc->sc_dc->dc_cmap.g[i];
                        ndac->bt_cmap = sc->sc_dc->dc_cmap.b[i];
                }
        }
        return (0);
}

void
omfb_getdevconfig(paddr_t paddr, struct om_hwdevconfig *dc)
{
        struct rasops_info *ri;
        union {
                struct { short h, v; } p;
                u_int32_t u;
        } rfcnt;

        /*
         * If this is the first time call, check how many planes we really
         * have.  This method is for 1, 4, and 8 bpp boards, must be checked
         * different way for 24 bpp board...
         */
        if ((hwplanebits > 0) && (dc->dc_depth_checked == 0)) {
                int i;
                u_int32_t *max, save;

                for (i = 0; i < 8; i++) {
                        max = (u_int32_t *)trunc_page(OMFB_FB_RADDR
                            + OMFB_FB_PLANESIZE * i);
                        save = *max;
                        *(volatile uint32_t *)max = 0x5a5a5a5a;
                        if (*max != 0x5a5a5a5a)
                                break;
                        *max = save;
                }
                hwplanebits = i;        /* should be 1, 4, or 8 */

                dc->dc_depth_checked = 1;
        }

        dc->dc_wid = 1280;
        dc->dc_ht = 1024;
        dc->dc_depth = hwplanebits;
        dc->dc_rowbytes = 2048 / 8;
        dc->dc_cmsize = (hwplanebits == 1) ? 0 : 1 << hwplanebits;
        dc->dc_videobase = paddr;

        /* set default colormap */
        omfb_set_default_cmap(dc);

        /* adjust h/v origin on screen */
        rfcnt.p.h = 7;
        rfcnt.p.v = -27;
        /* single write of 0x007ffe6 */
        *(volatile u_int32_t *)OMFB_RFCNT = rfcnt.u;

        /* clear the screen */
        omfb_clear_framebuffer(dc);

        /* initialize the raster */
        ri = &dc->dc_ri;
        ri->ri_width = dc->dc_wid;
        ri->ri_height = dc->dc_ht;
        ri->ri_depth = 1;       /* since planes are independently addressed */
        ri->ri_stride = dc->dc_rowbytes;
        ri->ri_bits = (void *)dc->dc_videobase;
        ri->ri_flg = RI_CENTER;
        ri->ri_hw = dc;

        rasops_init(ri, 35, 80);

        ri->ri_ops.copycols = om_copycols;
        ri->ri_ops.erasecols = om_erasecols;
        ri->ri_ops.copyrows = om_copyrows;
        ri->ri_ops.eraserows = om_eraserows;
        omfb_stdscreen.ncols = ri->ri_cols;
        omfb_stdscreen.nrows = ri->ri_rows;
        omfb_stdscreen.textops = &ri->ri_ops;
        omfb_stdscreen.fontwidth = ri->ri_font->fontwidth;
        omfb_stdscreen.fontheight = ri->ri_font->fontheight;

        /* set up depth-depend functions and so on */
        if ((hwplanebits == 4) || (hwplanebits == 8)) {
                setup_omrasops4(ri);
        } else {
                setup_omrasops1(ri);
        }
}

int
omfb_alloc_screen(void *v, const struct wsscreen_descr *type, void **cookiep,
    int *curxp, int *curyp, uint32_t *attrp)
{
        struct omfb_softc *sc = v;
        struct rasops_info *ri = &sc->sc_dc->dc_ri;

        if (sc->nscreens > 0)
                return (ENOMEM);

        *cookiep = ri;
        *curxp = 0;
        *curyp = 0;
        ri->ri_ops.pack_attr(ri, 0, 0, 0, attrp);
        sc->nscreens++;
        return (0);
}

void
omfb_free_screen(void *v, void *cookie)
{
        struct omfb_softc *sc = v;

        sc->nscreens--;
}

int
omfb_show_screen(void *v, void *cookie, int waitok,
    void (*cb)(void *, int, int), void *cbarg)
{
        return 0;
}

int
omfb_load_font(void *v, void *emulcookie, struct wsdisplay_font *font)
{
        struct omfb_softc *sc = v;
        struct rasops_info *ri = &sc->sc_dc->dc_ri;

        return rasops_load_font(ri, emulcookie, font);
}

int
omfb_list_font(void *v, struct wsdisplay_font *font)
{
        struct omfb_softc *sc = v;
        struct rasops_info *ri = &sc->sc_dc->dc_ri;

        return rasops_list_font(ri, font);
}

/*
 * Change `pseudo' depth, set the default colormap, and clear frame buffer.
 * Note: when called with depth == 0, change to the original hardware depth. 
 */
int
omfb_set_gfxmode(struct omfb_softc *sc, struct wsdisplay_gfx_mode *wsd_gfxmode)
{
        /* LUNA's fb is fixed size */
        if ((wsd_gfxmode->width != sc->sc_dc->dc_wid)
            || (wsd_gfxmode->height != sc->sc_dc->dc_ht))
                return -1;

        /* if depth == 0, set the original hardware depth */
        if (wsd_gfxmode->depth == 0)
                wsd_gfxmode->depth = hwplanebits;

        switch (wsd_gfxmode->depth) {
        case 1:
                /* all frame buffer support this */
                sc->sc_dc->dc_depth = 1;
                sc->sc_dc->dc_cmsize = 0;
                setup_omrasops1(&sc->sc_dc->dc_ri);
                break;
        case 4:
                if ((hwplanebits == 4) || (hwplanebits == 8)) {
                        sc->sc_dc->dc_depth = 4;
                        sc->sc_dc->dc_cmsize = 16;
                        setup_omrasops4(&sc->sc_dc->dc_ri);
                        break;
                } else
                        return -1;
        case 8:
                if (hwplanebits == 8) {
                        sc->sc_dc->dc_depth = 8;
                        sc->sc_dc->dc_cmsize = 256;
                        setup_omrasops4(&sc->sc_dc->dc_ri);
                        break;
                } else
                        return -1;
        default:
                return -1;
        }

        omfb_set_default_cmap(sc->sc_dc);
        omfb_clear_framebuffer(sc->sc_dc);

        return 0;
}

/*
 * Clear all planes of frame buffer
 */
void
omfb_clear_framebuffer(struct om_hwdevconfig *dc)
{
        int i;

        *(volatile u_int32_t *)OMFB_PLANEMASK = 0xff;   /* all planes */
        ((volatile u_int32_t *)OMFB_ROPFUNC)[5] = ~0;   /* ROP copy */
        for (i = 0; i < dc->dc_ht * dc->dc_rowbytes / sizeof(u_int32_t); i++)
                *((volatile u_int32_t *)dc->dc_videobase + i) = 0;
        *(volatile u_int32_t *)OMFB_PLANEMASK = 0x01;   /* plane #0 only */
}

/*
 * Set default colormap; white on black for 1bpp, ANSI 16 colors for 4/8 bpp.
 *
 * Note about workaround for 8bpp frame buffer:
 *
 * Current LUNA wscons touches only first 4 planes (plane #0-#3), but
 * other program (e.g. mlterm-fb) can use all 8 planes on an 8bpp
 * frame buffer.  When such program exits, it may not clear all planes,
 * so there may be some visible garbage data on the other 4 planes
 * (plane #4-#7) when we use default 256 rasops_cmap directly.
 *
 * We should manage all 8 planes on LUNA, but that will be too much
 * overhead for 16 colors wscons.  So, by repeating 16 colors in 256
 * colormap, we can ignore the values on the other 4 planes.
 */
void
omfb_set_default_cmap(struct om_hwdevconfig *dc)
{
        int i;

        if (hwplanebits == 1) {
                struct bt454 *odac = (struct bt454 *)OMFB_RAMDAC;
                /*
                 * On 1bpp framebuffer, only plane P0 has framebuffer memory
                 * and other planes seems pulled up, i.e. always 1.
                 * Set white only for a palette (P0,P1,P2,P3) = (1,1,1,1).
                 */
                odac->bt_addr = 0;
                for (i = 0; i < 15; i++) {
                        odac->bt_cmap = dc->dc_cmap.r[i] = 0;
                        odac->bt_cmap = dc->dc_cmap.g[i] = 0;
                        odac->bt_cmap = dc->dc_cmap.b[i] = 0;
                }
                /*
                 * The B/W video connector is connected to IOG of Bt454,
                 * and IOR and IOB are unused.
                 */
                odac->bt_cmap = dc->dc_cmap.r[15] = 0;
                odac->bt_cmap = dc->dc_cmap.g[15] = 255;
                odac->bt_cmap = dc->dc_cmap.b[15] = 0;
        } else if (hwplanebits == 4) {
                struct bt454 *odac = (struct bt454 *)OMFB_RAMDAC;

                odac->bt_addr = 0;
                if (dc->dc_depth == 1) {
                        /* white on black */
                        for (i = 0; i < 16; i++) {
                                u_int8_t val = i % 2 ? 255 : 0;

                                odac->bt_cmap = dc->dc_cmap.r[i] = val;
                                odac->bt_cmap = dc->dc_cmap.g[i] = val;
                                odac->bt_cmap = dc->dc_cmap.b[i] = val;
                        }
                } else {
                        for (i = 0; i < 16; i++) {
                        /* Set ANSI 16 colors */
                                odac->bt_cmap = dc->dc_cmap.r[i]
                                    = rasops_cmap[i * 3];
                                odac->bt_cmap = dc->dc_cmap.g[i]
                                    = rasops_cmap[i * 3 + 1];
                                odac->bt_cmap = dc->dc_cmap.b[i]
                                    = rasops_cmap[i * 3 + 2];
                        }
                }
        } else if (hwplanebits == 8) {
                struct bt458 *ndac = (struct bt458 *)OMFB_RAMDAC;

                /*
                 * Initialize the Bt458.  When we write to control registers,
                 * the address is not incremented automatically. So we specify
                 * it ourselves for each control register.
                 */
                ndac->bt_addr = 0x04;
                ndac->bt_ctrl = 0xff; /* all planes will be read */
                ndac->bt_addr = 0x05;
                ndac->bt_ctrl = 0x00; /* all planes have non-blink */
                ndac->bt_addr = 0x06;
                ndac->bt_ctrl = 0x40; /* palette enabled, ovly plane disabled */
                ndac->bt_addr = 0x07;
                ndac->bt_ctrl = 0x00; /* no test mode */

                ndac->bt_addr = 0;
                if (dc->dc_depth == 1) {
                        /* white on black */
                        for (i = 0; i < 256; i++) {
                                u_int8_t val = i % 2 ? 255 : 0;

                                ndac->bt_cmap = dc->dc_cmap.r[i] = val;
                                ndac->bt_cmap = dc->dc_cmap.g[i] = val;
                                ndac->bt_cmap = dc->dc_cmap.b[i] = val;
                        }
                } else {
                        /*
                         * Set ANSI 16 colors.  On 8bpp frame buffer, repeat
                         * 16 colors in 256 colormap as described above.
                         */
                        for (i = 0; i < 256; i++) {
                                int index = i % 16;
                                ndac->bt_cmap = dc->dc_cmap.r[i]
                                    = rasops_cmap[index * 3];
                                ndac->bt_cmap = dc->dc_cmap.g[i]
                                    = rasops_cmap[index * 3 + 1];
                                ndac->bt_cmap = dc->dc_cmap.b[i]
                                    = rasops_cmap[index * 3 + 2];
                        }
                }
        }
}