/*      $NetBSD: isa_machdep.c,v 1.21 2025/05/01 05:36:02 tsutsui Exp $ */

/*
 * Copyright (c) 2001 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Wayne Knowles
 *
 * 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/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: isa_machdep.c,v 1.21 2025/05/01 05:36:02 tsutsui Exp $");

#define __INTR_PRIVATE

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

#include <machine/sysconf.h>
#include <machine/autoconf.h>
#include <machine/mainboard.h>
#include <machine/bus.h>

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

static int      mipscoisabusprint(void *, const char *);
static int      isabusmatch(device_t, cfdata_t, void *);
static void     isabusattach(device_t, device_t, void *);

struct isabus_softc {
        struct mipsco_isa_chipset sc_isa_ic;
};

CFATTACH_DECL_NEW(isabus, sizeof(struct isabus_softc),
    isabusmatch, isabusattach, NULL, NULL);

extern struct cfdriver isabus_cd;

static struct mipsco_bus_space  isa_io_bst, isa_mem_bst, isa_ctl_bst;
static struct mipsco_bus_dma_tag isa_dmatag;

static void isa_bus_space_init(struct mipsco_bus_space *, const char *,
                                     paddr_t, size_t);
int    isa_intr(void *);


int
isabusmatch(device_t parent, cfdata_t cfp, void *aux)
{
        struct confargs *ca = aux;

        if (strcmp(ca->ca_name, isabus_cd.cd_name) != 0)
                return 0;
        return 1;
}

static void
isa_bus_space_init(struct mipsco_bus_space *bst, const char *type, paddr_t paddr, size_t len)
{
        vaddr_t vaddr = MIPS_PHYS_TO_KSEG1(paddr); /* XXX */

        /* Setup default bus_space */
        mipsco_bus_space_init(bst, type, paddr, vaddr, 0x0, len);

        /* ISA bus maps 1 word for every byte, therefore stride = 2 */
        mipsco_bus_space_set_aligned_stride(bst, 2);

        /*
         * ISA bus will do an automatic byte swap, but when accessing
         * memory using bus_space_stream functions we need to byte swap
         * to reverse the one performed in hardware
         */
        bst->bs_bswap = 1;

        bst->bs_intr_establish = (void *)isa_intr_establish;

        printf(" %s %p", type, (void *)vaddr);
}


void
isabusattach(device_t parent, device_t self, void *aux)
{
        struct isabus_softc *sc = device_private(self);
        struct mipsco_isa_chipset *ic = &sc->sc_isa_ic;
        struct isabus_attach_args iba;

        printf(":");

        iba.iba_iot     = &isa_io_bst;
        iba.iba_memt    = &isa_mem_bst;
        iba.iba_dmat    = &isa_dmatag;
        iba.iba_ic      = ic;

        isa_bus_space_init(&isa_io_bst,  "isa_io",   PIZAZZ_ISA_IOBASE,
                PIZAZZ_ISA_IOSIZE);

        isa_bus_space_init(&isa_mem_bst, "isa_mem",  PIZAZZ_ISA_MEMBASE,
                PIZAZZ_ISA_MEMSIZE);

        isa_bus_space_init(&isa_ctl_bst, "isa_intr", PIZAZZ_ISA_INTRLATCH,
                sizeof(uint32_t));

        _bus_dma_tag_init(&isa_dmatag);

        ic->ic_bst = &isa_ctl_bst;

        if (bus_space_map(ic->ic_bst, 0x00000, sizeof(uint32_t),
                          BUS_SPACE_MAP_LINEAR, &ic->ic_bsh) != 0) {
                printf(": can't map intrreg\n");
                return;
        }
        
        /* Clear ISA interrupt latch */
        bus_space_write_4(ic->ic_bst, ic->ic_bsh, 0, 0);

        evcnt_attach_dynamic(&ic->ic_intrcnt, EVCNT_TYPE_INTR, NULL,
                             device_xname(self), "intr");

        LIST_INIT(&ic->intr_q);
        (*platform.intr_establish)(SYS_INTR_ATBUS, isa_intr, ic);

        printf("\n");
        config_found(self, &iba, mipscoisabusprint, CFARGS_NONE);
}

int
mipscoisabusprint(void *aux, const char *name)
{
        if (name == NULL)
                return UNCONF;
        return QUIET;
}

void
isa_attach_hook(device_t parent, device_t self, struct isabus_attach_args *iba)
{
}

void
isa_detach_hook(isa_chipset_tag_t ic, device_t self)
{
}

const struct evcnt *
isa_intr_evcnt(isa_chipset_tag_t ic, int irq)
{
        /* XXX for now, no evcnt parent reported */
        return NULL;
}

void *
isa_intr_establish(isa_chipset_tag_t ic, int intr, int type, int level, int (*ih_fun)(void*), void *ih_arg)
        /* type:   XXX not yet */
        /* level:   XXX not yet */
{
        struct mipsco_intrhand *ih;

        ih = kmem_alloc(sizeof *ih, KM_SLEEP);
        ih->ih_fun = ih_fun;
        ih->ih_arg  = ih_arg;
        LIST_INSERT_HEAD(&ic->intr_q, ih, ih_q);
        return ih;
}

void
isa_intr_disestablish(isa_chipset_tag_t ic, void *cookie)
{
        struct mipsco_intrhand *ih = cookie;

        LIST_REMOVE(ih, ih_q);
        kmem_free(ih, sizeof(*ih));
}

int
isa_intr_alloc(isa_chipset_tag_t ic, int mask, int type, int *irq)
{
        return 0;
}

int
isa_intr(void *arg)
{
        struct mipsco_isa_chipset *ic = (struct mipsco_isa_chipset *)arg;
        struct mipsco_intrhand *ih;
        int rv, handled;

        ic->ic_intrcnt.ev_count++;

        handled = 0;
        LIST_FOREACH(ih, &ic->intr_q, ih_q) {
                /*
                 * The handler returns one of three values:
                 *   0: This interrupt wasn't for me.
                 *   1: This interrupt was for me.
                 *  -1: This interrupt might have been for me, but I can't say
                 *      for sure.
                 */
                rv = (*ih->ih_fun)(ih->ih_arg);
                handled |= (rv != 0);
        }

        /* Clear ISA interrupt latch */
        bus_space_write_4(ic->ic_bst, ic->ic_bsh, 0, 0);

        return handled;
}