/* $NetBSD: sableio.c,v 1.16 2021/08/07 16:18:41 thorpej Exp $ */

/*-
 * Copyright (c) 1999, 2000 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Jason R. Thorpe.
 *
 * 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.
 */

/*
 * Driver glue for the Sable STDIO module.
 *
 * This is kind of a hack.  The STDIO is really a junk I/O module with
 * your regular ISA junk peripherals and their regular ISA I/O addresses.
 * However, the main issue we have here is *interrupts*.  Not only are
 * devices IRQs strange (i.e. not what you would expect to find if they
 * were attached to a real ISA) IRQs, the keyboard controller isn't even
 * connected to the (E)ISA IRQ space at all!
 *
 * In short, we're gluing together the following things:
 *
 *      - Standard ISA junk I/O chip
 *      - ISA DMA
 *      - Pre-mapped "PCI" interrupts that are *edge triggered*
 */

#include <sys/cdefs.h>                  /* RCS ID & Copyright macro defns */

__KERNEL_RCSID(0, "$NetBSD: sableio.c,v 1.16 2021/08/07 16:18:41 thorpej Exp $");

#include "isadma.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>

#include <dev/isa/isareg.h>
#include <dev/isa/isavar.h>
#include <dev/isa/isadmavar.h>

#include <dev/pci/pcivar.h>

#include <alpha/sableio/sableiovar.h>

#include "locators.h"

/*
 * The devices built-in to the Sable STDIO module.
 */
static const struct sableio_dev {
        const char *sd_name;            /* device name */
        bus_addr_t sd_ioaddr;           /* I/O space address */
        int sd_sableirq[2];             /* Sable IRQs */
        int sd_drq;                     /* ISA DRQ */
} sableio_devs[] = {
        /*
         * See alpha/pci/pci_2100_a500.c for interrupt information.
         */
        { "pckbc",      IO_KBD,         { 6, 3 },       -1 },
        { "fdc",        IO_FD1,         { 7, -1 },      2 },
        { "com",        IO_COM1,        { 15, -1 },     -1 },
        { "com",        IO_COM2,        { 8, -1 },      -1 },
        { "lpt",        IO_LPT3,        { 9, -1 },      -1 },
        { NULL,         0,              { -1, -1 },     -1 },
};

struct sableio_softc {
        device_t        sc_dev;         /* base device */

        /*
         * We have to deal with ISA DMA, so that means we have to
         * hold the ISA chipset, since we attach STDIO devices
         * before we attach the PCI (and thus EISA) bus.
         */
        struct alpha_isa_chipset sc_isa_chipset;
};

static int      sableio_match(device_t, cfdata_t, void *);
static void     sableio_attach(device_t, device_t, void *);

CFATTACH_DECL_NEW(sableio, sizeof(struct sableio_softc),
    sableio_match, sableio_attach, NULL, NULL);

static int      sableio_print(void *, const char *);

static struct sableio_softc *sableio_attached;

static int
sableio_match(device_t parent, cfdata_t cf, void *aux)
{
        struct pcibus_attach_args *pba = aux;

        /*
         * These are really ISA devices, and thus must be on
         * PCI bus 0.
         */
        if (cf->cf_loc[SABLEIOBUSCF_BUS] != SABLEIOBUSCF_BUS_DEFAULT &&
            cf->cf_loc[SABLEIOBUSCF_BUS] != pba->pba_bus)
                return (0);

        /* sanity */
        if (pba->pba_bus != 0)
                return (0);

        /* There can be only one. */
        if (sableio_attached != NULL)
                return (0);

        return (1);
}

static void
sableio_attach(device_t parent, device_t self, void *aux)
{
        struct sableio_softc *sc = device_private(self);
        struct pcibus_attach_args *pba = aux;
        struct sableio_attach_args sa;
        bus_dma_tag_t dmat;
        int i;
        int locs[SABLEIOCF_NLOCS];

        aprint_normal(": Sable STDIO module\n");

        sableio_attached = sc;
        sc->sc_dev = self;

        dmat = alphabus_dma_get_tag(pba->pba_dmat, ALPHA_BUS_ISA);

#if NISADMA > 0
        /*
         * Initialize our DMA state.
         */
        isa_dmainit(&sc->sc_isa_chipset, pba->pba_iot, dmat, self);
#endif

        for (i = 0; sableio_devs[i].sd_name != NULL; i++) {
                sa.sa_name = sableio_devs[i].sd_name;
                sa.sa_ioaddr = sableio_devs[i].sd_ioaddr;
                sa.sa_sableirq[0] = sableio_devs[i].sd_sableirq[0];
                sa.sa_sableirq[1] = sableio_devs[i].sd_sableirq[1];
                sa.sa_drq = sableio_devs[i].sd_drq;

                sa.sa_iot = pba->pba_iot;
                sa.sa_dmat = dmat;
                sa.sa_ic = &sc->sc_isa_chipset;
                sa.sa_pc = pba->pba_pc;

                locs[SABLEIOCF_PORT] = sableio_devs[i].sd_ioaddr;

                config_found(self, &sa, sableio_print,
                    CFARGS(.submatch = config_stdsubmatch,
                           .locators = locs));
        }
}

static int
sableio_print(void *aux, const char *pnp)
{
        struct sableio_attach_args *sa = aux;

        if (pnp != NULL)
                aprint_normal("%s at %s", sa->sa_name, pnp);

        aprint_normal(" port 0x%lx", sa->sa_ioaddr);
        return (UNCONF);
}

isa_chipset_tag_t
sableio_pickisa(void)
{

        if (sableio_attached == NULL)
                panic("sableio_pickisa");

        return (&sableio_attached->sc_isa_chipset);
}