/* $NetBSD: pcdisplay.c,v 1.47 2021/08/07 16:19:12 thorpej Exp $ */

/*
 * Copyright (c) 1998
 *      Matthias Drochner.  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.
 * 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 AUTHOR ``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 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/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: pcdisplay.c,v 1.47 2021/08/07 16:19:12 thorpej Exp $");

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

#include <dev/isa/isavar.h>

#include <dev/ic/mc6845reg.h>
#include <dev/ic/pcdisplayvar.h>
#include <dev/isa/pcdisplayvar.h>

#include <dev/ic/pcdisplay.h>

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

#include "pcweasel.h"
#if NPCWEASEL > 0
#include <dev/isa/weaselreg.h>
#include <dev/isa/weaselvar.h>
#endif

struct pcdisplay_config {
        struct pcdisplayscreen pcs;
        struct pcdisplay_handle dc_ph;
        int mono;
};

struct pcdisplay_softc {
        struct pcdisplay_config *sc_dc;
        int nscreens;
#if NPCWEASEL > 0
        struct weasel_handle sc_weasel;
#endif
};

static int pcdisplayconsole, pcdisplay_console_attached;
static struct pcdisplay_config pcdisplay_console_dc;

int     pcdisplay_match(device_t, cfdata_t, void *);
void    pcdisplay_attach(device_t, device_t, void *);

static int pcdisplay_is_console(bus_space_tag_t);
static int pcdisplay_probe_col(bus_space_tag_t, bus_space_tag_t);
static int pcdisplay_probe_mono(bus_space_tag_t, bus_space_tag_t);
static void pcdisplay_init(struct pcdisplay_config *,
                             bus_space_tag_t, bus_space_tag_t,
                             int);
static int pcdisplay_allocattr(void *, int, int, int, long *);

CFATTACH_DECL_NEW(pcdisplay, sizeof(struct pcdisplay_softc),
    pcdisplay_match, pcdisplay_attach, NULL, NULL);

const struct wsdisplay_emulops pcdisplay_emulops = {
        pcdisplay_cursor,
        pcdisplay_mapchar,
        pcdisplay_putchar,
        pcdisplay_copycols,
        pcdisplay_erasecols,
        pcdisplay_copyrows,
        pcdisplay_eraserows,
        pcdisplay_allocattr,
        NULL,   /* replaceattr */
};

const struct wsscreen_descr pcdisplay_scr = {
        "80x25", 80, 25,
        &pcdisplay_emulops,
        0, 0, /* no font support */
        WSSCREEN_REVERSE, /* that's minimal... */
        NULL, /* modecookie */
};

const struct wsscreen_descr *_pcdisplay_scrlist[] = {
        &pcdisplay_scr,
};

const struct wsscreen_list pcdisplay_screenlist = {
        sizeof(_pcdisplay_scrlist) / sizeof(struct wsscreen_descr *),
        _pcdisplay_scrlist
};

static int pcdisplay_ioctl(void *, void *, u_long, void *, int, struct lwp *);
static paddr_t pcdisplay_mmap(void *, void *, off_t, int);
static int pcdisplay_alloc_screen(void *, const struct wsscreen_descr *,
                                       void **, int *, int *, long *);
static void pcdisplay_free_screen(void *, void *);
static int pcdisplay_show_screen(void *, void *, int,
                                      void (*) (void *, int, int), void *);

const struct wsdisplay_accessops pcdisplay_accessops = {
        pcdisplay_ioctl,
        pcdisplay_mmap,
        pcdisplay_alloc_screen,
        pcdisplay_free_screen,
        pcdisplay_show_screen,
        NULL, /* load_font */
        NULL, /* pollc */
        NULL, /* scroll */
};

static int
pcdisplay_probe_col(bus_space_tag_t iot, bus_space_tag_t memt)
{
        bus_space_handle_t memh, ioh_6845;
        u_int16_t oldval, val;

        if (bus_space_map(memt, 0xb8000, 0x8000, 0, &memh))
                return (0);
        oldval = bus_space_read_2(memt, memh, 0);
        bus_space_write_2(memt, memh, 0, 0xa55a);
        val = bus_space_read_2(memt, memh, 0);
        bus_space_write_2(memt, memh, 0, oldval);
        bus_space_unmap(memt, memh, 0x8000);
        if (val != 0xa55a)
                return (0);

        if (bus_space_map(iot, 0x3d0, 0x10, 0, &ioh_6845))
                return (0);
        bus_space_unmap(iot, ioh_6845, 0x10);

        return (1);
}

static int
pcdisplay_probe_mono(bus_space_tag_t iot, bus_space_tag_t memt)
{
        bus_space_handle_t memh, ioh_6845;
        u_int16_t oldval, val;

        if (bus_space_map(memt, 0xb0000, 0x8000, 0, &memh))
                return (0);
        oldval = bus_space_read_2(memt, memh, 0);
        bus_space_write_2(memt, memh, 0, 0xa55a);
        val = bus_space_read_2(memt, memh, 0);
        bus_space_write_2(memt, memh, 0, oldval);
        bus_space_unmap(memt, memh, 0x8000);
        if (val != 0xa55a)
                return (0);

        if (bus_space_map(iot, 0x3b0, 0x10, 0, &ioh_6845))
                return (0);
        bus_space_unmap(iot, ioh_6845, 0x10);

        return (1);
}

static void
pcdisplay_init(struct pcdisplay_config *dc, bus_space_tag_t iot,
    bus_space_tag_t memt, int mono)
{
        struct pcdisplay_handle *ph = &dc->dc_ph;
        int cpos;

        ph->ph_iot = iot;
        ph->ph_memt = memt;
        dc->mono = mono;

        if (bus_space_map(memt, mono ? 0xb0000 : 0xb8000, 0x8000,
            BUS_SPACE_MAP_CACHEABLE, &ph->ph_memh))
                panic("pcdisplay_init: cannot map memory");
        if (bus_space_map(iot, mono ? 0x3b0 : 0x3d0, 0x10,
                          0, &ph->ph_ioh_6845))
                panic("pcdisplay_init: cannot map io");

        /*
         * initialize the only screen
         */
        dc->pcs.hdl = ph;
        dc->pcs.type = &pcdisplay_scr;
        dc->pcs.active = 1;
        dc->pcs.mem = NULL;

        cpos = pcdisplay_6845_read(ph, cursorh) << 8;
        cpos |= pcdisplay_6845_read(ph, cursorl);

        /* make sure we have a valid cursor position */
        if (cpos < 0 || cpos >= pcdisplay_scr.nrows * pcdisplay_scr.ncols)
                cpos = 0;

        dc->pcs.dispoffset = 0;

        dc->pcs.cursorrow = cpos / pcdisplay_scr.ncols;
        dc->pcs.cursorcol = cpos % pcdisplay_scr.ncols;
        pcdisplay_cursor_init(&dc->pcs, 1);
}

int
pcdisplay_match(device_t parent, cfdata_t match, void *aux)
{
        struct isa_attach_args *ia = aux;
        int mono;

        if (ISA_DIRECT_CONFIG(ia))
                return (0);

        /* If values are hardwired to something that they can't be, punt. */
        if (ia->ia_nio < 1 ||
            (ia->ia_io[0].ir_addr != ISA_UNKNOWN_PORT &&
             ia->ia_io[0].ir_addr != 0x3d0 &&
             ia->ia_io[0].ir_addr != 0x3b0))
                return (0);

        if (ia->ia_niomem < 1 ||
            (ia->ia_iomem[0].ir_addr != ISA_UNKNOWN_IOMEM &&
             ia->ia_iomem[0].ir_addr != 0xb8000 &&
             ia->ia_iomem[0].ir_addr != 0xb0000))
                return (0);
        if (ia->ia_iomem[0].ir_size != 0 &&
            ia->ia_iomem[0].ir_size != 0x8000)
                return (0);

        if (ia->ia_nirq > 0 &&
            ia->ia_irq[0].ir_irq != ISA_UNKNOWN_IRQ)
                return (0);

        if (ia->ia_ndrq > 0 &&
            ia->ia_drq[0].ir_drq != ISA_UNKNOWN_DRQ)
                return (0);

        if (pcdisplay_is_console(ia->ia_iot))
                mono = pcdisplay_console_dc.mono;
        else if (ia->ia_io[0].ir_addr != 0x3b0 &&
                 ia->ia_iomem[0].ir_addr != 0xb0000 &&
                 pcdisplay_probe_col(ia->ia_iot, ia->ia_memt))
                mono = 0;
        else if (ia->ia_io[0].ir_addr != 0x3d0 &&
                 ia->ia_iomem[0].ir_addr != 0xb8000 &&
                 pcdisplay_probe_mono(ia->ia_iot, ia->ia_memt))
                mono = 1;
        else
                return (0);

        ia->ia_nio = 1;
        ia->ia_io[0].ir_addr = mono ? 0x3b0 : 0x3d0;
        ia->ia_io[0].ir_size = 0x10;

        ia->ia_niomem = 1;
        ia->ia_iomem[0].ir_addr = mono ? 0xb0000 : 0xb8000;
        ia->ia_iomem[0].ir_size = 0x8000;

        ia->ia_nirq = 0;
        ia->ia_ndrq = 0;

        return (1);
}

void
pcdisplay_attach(device_t parent, device_t self, void *aux)
{
        struct isa_attach_args *ia = aux;
        struct pcdisplay_softc *sc = device_private(self);
        int console;
        struct pcdisplay_config *dc;
        struct wsemuldisplaydev_attach_args aa;

        printf("\n");

        console = pcdisplay_is_console(ia->ia_iot);

        if (console) {
                dc = &pcdisplay_console_dc;
                sc->nscreens = 1;
                pcdisplay_console_attached = 1;
        } else {
                dc = malloc(sizeof(struct pcdisplay_config),
                            M_DEVBUF, M_WAITOK);
                if (ia->ia_io[0].ir_addr != 0x3b0 &&
                    ia->ia_iomem[0].ir_addr != 0xb0000 &&
                    pcdisplay_probe_col(ia->ia_iot, ia->ia_memt))
                        pcdisplay_init(dc, ia->ia_iot, ia->ia_memt, 0);
                else if (ia->ia_io[0].ir_addr != 0x3d0 &&
                         ia->ia_iomem[0].ir_addr != 0xb8000 &&
                         pcdisplay_probe_mono(ia->ia_iot, ia->ia_memt))
                        pcdisplay_init(dc, ia->ia_iot, ia->ia_memt, 1);
                else
                        panic("pcdisplay_attach: display disappeared");
        }
        sc->sc_dc = dc;

#if NPCWEASEL > 0
        /*
         * If the display is monochrome, check to see if we have
         * a PC-Weasel, and initialize its special features.
         */
        if (dc->mono) {
                sc->sc_weasel.wh_st = dc->dc_ph.ph_memt;
                sc->sc_weasel.wh_sh = dc->dc_ph.ph_memh;
                sc->sc_weasel.wh_parent = self;
                weasel_isa_init(&sc->sc_weasel);
        }
#endif /* NPCWEASEL > 0 */

        aa.console = console;
        aa.scrdata = &pcdisplay_screenlist;
        aa.accessops = &pcdisplay_accessops;
        aa.accesscookie = sc;

        config_found(self, &aa, wsemuldisplaydevprint, CFARGS_NONE);
}


int
pcdisplay_cnattach(bus_space_tag_t iot, bus_space_tag_t memt)
{
        int mono;

        if (pcdisplay_probe_col(iot, memt))
                mono = 0;
        else if (pcdisplay_probe_mono(iot, memt))
                mono = 1;
        else
                return (ENXIO);

        pcdisplay_init(&pcdisplay_console_dc, iot, memt, mono);

        wsdisplay_cnattach(&pcdisplay_scr, &pcdisplay_console_dc,
                           pcdisplay_console_dc.pcs.cursorcol,
                           pcdisplay_console_dc.pcs.cursorrow,
                           FG_LIGHTGREY | BG_BLACK);

        pcdisplayconsole = 1;
        return (0);
}

static int
pcdisplay_is_console(bus_space_tag_t iot)
{
        if (pcdisplayconsole &&
            !pcdisplay_console_attached &&
            bus_space_is_equal(iot, pcdisplay_console_dc.dc_ph.ph_iot))
                return (1);
        return (0);
}

static int
pcdisplay_ioctl(void *v, void *vs, u_long cmd,
    void *data, int flag, struct lwp *l)
{
        /*
         * XXX "do something!"
         */
        return (EPASSTHROUGH);
}

static paddr_t
pcdisplay_mmap(void *v, void *vs, off_t offset, int prot)
{
        return (-1);
}

static int
pcdisplay_alloc_screen(void *v, const struct wsscreen_descr *type,
    void **cookiep, int *curxp, int *curyp, long *defattrp)
{
        struct pcdisplay_softc *sc = v;

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

        *cookiep = sc->sc_dc;
        *curxp = 0;
        *curyp = 0;
        *defattrp = FG_LIGHTGREY | BG_BLACK;
        sc->nscreens++;
        return (0);
}

static void
pcdisplay_free_screen(void *v, void *cookie)
{
        struct pcdisplay_softc *sc = v;

        if (sc->sc_dc == &pcdisplay_console_dc)
                panic("pcdisplay_free_screen: console");

        sc->nscreens--;
}

static int
pcdisplay_show_screen(void *v, void *cookie, int waitok,
    void (*cb)(void *, int, int), void *cbarg)
{
#ifdef DIAGNOSTIC
        struct pcdisplay_softc *sc = v;

        if (cookie != sc->sc_dc)
                panic("pcdisplay_show_screen: bad screen");
#endif
        return (0);
}

static int
pcdisplay_allocattr(void *id, int fg, int bg, int flags, long *attrp)
{
        if (flags & WSATTR_REVERSE)
                *attrp = FG_BLACK | BG_LIGHTGREY;
        else
                *attrp = FG_LIGHTGREY | BG_BLACK;
        return (0);
}