/*	$NetBSD: xel.c,v 1.18 2014/03/26 08:17:59 christos 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 1.18 2014/03/26 08:17:59 christos 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;
}

extern int *nofault;

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 = (int *) &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 = (int *) 0;
		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 = (int *) 0;
		return 0;
	}
	sram[0] = 0xaaaaaaaa;
	sram[1] = 0x55555555;
	if (sram[0] != 0xaaaaaaaa || sram[1] != 0x55555555) {
		sram[0] = b1;
		sram[1] = b2;
		nofault = (int *) 0;
		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;
}