/*      $NetBSD: xel.c,v 1.19 2026/04/26 10:52:16 thorpej Exp $ */

/*
 * Copyright (c) 1998 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Minoura Makoto.
 *
 * 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.
 */

/*
 * TSR Xellent30 driver.
 * Detect Xellent30, and reserve its I/O area.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: xel.c,v 1.19 2026/04/26 10:52:16 thorpej Exp $");

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

#include <machine/cpu.h>
#include <machine/bus.h>

#include <arch/x68k/dev/intiovar.h>

static paddr_t xel_addr(device_t, cfdata_t, struct intio_attach_args *);
static int xel_probe(paddr_t);
static int xel_match(device_t, cfdata_t, void *);
static void xel_attach(device_t, device_t, void *);

struct xel_softc {
        bus_space_tag_t sc_bst;
        bus_space_handle_t sc_bh;
};

CFATTACH_DECL_NEW(xel, sizeof(struct xel_softc),
    xel_match, xel_attach, NULL, NULL);

static paddr_t xel_addrs[] = { 0xec0000, 0xec4000, 0xec8000, 0xecc000 };

#define XEL_MODE_RAM_LOWER      0x00
#define XEL_MODE_RAM_HIGHER     0x01
#define XEL_MODE_UNMAP_RAM      0x00
#define XEL_MODE_MAP_RAM        0x02
#define XEL_MODE_MPU_000        0x00
#define XEL_MODE_MPU_030        0x04

#define XEL_RAM_ADDR_LOWER      0xbc0000
#define XEL_RAM_ADDR_HIGHER     0xfc0000


static paddr_t
xel_addr(device_t parent, cfdata_t match, struct intio_attach_args *ia)
{
        paddr_t addr = 0;

        if (match->cf_addr == INTIOCF_ADDR_DEFAULT) {
                int i;

                for (i = 0; i < sizeof(xel_addrs)/sizeof(xel_addrs[0]); i++) {
                        if (xel_probe(xel_addrs[i])) {
                                addr = xel_addrs[i];
                                break;
                        }
                }
        } else {
                if (xel_probe((paddr_t) match->cf_addr))
                        addr = (paddr_t) match->cf_addr;
        }

        if (addr) {
                /* found! */
                ia->ia_addr = (int) addr;
                ia->ia_size = 0x4000;
                if (intio_map_allocate_region(parent, ia, INTIO_MAP_TESTONLY)
                    < 0)
                        return 0;
                else
                        return addr;
        }

        return 0;
}

static int
xel_probe(paddr_t addr)
{
        u_int32_t b1, b2;
        volatile u_int16_t *start = (volatile u_int16_t *)IIOV(addr);
        label_t faultbuf;
        volatile u_int32_t *sram = (volatile u_int32_t *)IIOV(XEL_RAM_ADDR_HIGHER);

        if (badaddr(start))
                return 0;

        nofault = &faultbuf;
        if (setjmp(&faultbuf)) {
                nofault = NULL;
                return 0;
        }

        b1 = sram[0];
        b2 = sram[1];
        /* Try to map the Xellent local memory. */
        start[0] = XEL_MODE_RAM_HIGHER | XEL_MODE_MAP_RAM | XEL_MODE_MPU_030;

#if 0
        /* the contents should be deferent. */
        if (b1 == sram[0] && b2 == sram[1]) {
                nofault = NULL;
                return 0;
        }
#else
        /* Try to write to the local memory. */
        sram[0] = 0x55555555;
        sram[1] = 0xaaaaaaaa;
        if (sram[0] != 0x55555555 || sram[1] != 0xaaaaaaaa) {
                sram[0] = b1;
                sram[1] = b2;
                nofault = NULL;
                return 0;
        }
        sram[0] = 0xaaaaaaaa;
        sram[1] = 0x55555555;
        if (sram[0] != 0xaaaaaaaa || sram[1] != 0x55555555) {
                sram[0] = b1;
                sram[1] = b2;
                nofault = NULL;
                return 0;
        }
        sram[0] = b1;
        sram[1] = b2;
#endif

        /* Unmap. */
        start[0] = XEL_MODE_UNMAP_RAM | XEL_MODE_MPU_030;

        nofault = NULL;
        return 1;
}

static int
xel_match(device_t parent, cfdata_t match, void *aux)
{
        struct intio_attach_args *ia = aux;

        if (strcmp(ia->ia_name, "xel") != 0)
                return 0;

        if (xel_addr(parent, match, ia)) {
#ifdef DIAGNOSTIC
                if (cputype != CPU_68030)
                        panic("Non-030 Xellent???");
#endif
                return 1;
        }
        return 0;
}

static void
xel_attach(device_t parent, device_t self, void *aux)
{
        struct xel_softc *sc = device_private(self);
        struct intio_attach_args *ia = aux;
        cfdata_t cf = device_cfdata(self);
        paddr_t addr;
        int r __diagused;

        addr = xel_addr(parent, cf, aux);
        sc->sc_bst = ia->ia_bst;
        ia->ia_addr = (int) addr;
        ia->ia_size = 0x4000;
        r = intio_map_allocate_region(parent, ia, INTIO_MAP_ALLOCATE);
#ifdef DIAGNOSTIC
        if (r)
                panic("IO map for Xellent30 corruption??");
#endif
        aprint_normal(": Xellent30 MPU Accelerator.\n");

        return;
}