/*      $NetBSD: xbox.c,v 1.26 2022/09/25 18:03:04 thorpej Exp $ */

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

/*
* Sbus expansion box.
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: xbox.c,v 1.26 2022/09/25 18:03:04 thorpej Exp $");

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

#include <sys/bus.h>
#include <dev/sbus/sbusvar.h>
#include <dev/sbus/xboxvar.h>
#include <machine/autoconf.h>

/*
* Xbox registers definitions.
*
* The xbox device can operate in two mode: "opaque" and "transparent".
* In opaque mode, all accesses to the xbox address space are directed
* to the xbox itself. In transparent mode, all accesses are mapped to
* the SBus cards in the expansion box.
*
* To access the xbox registers in transparent mode, you must write
* to the "write0" register. The layout of this register appears to
* be as follows:
*
*      bit 31-24: xbox key (identifies device when you cascade them)
*      bit 23-12: offset of register to access
*      bit 11-0:  value to write
*
* For instance, to switch to opaque mode:
*      (*sc->write0_reg) = (sc->sc_key << 24) | XAC_CTL1_OFFSET;
*
* (note we're not currently using any of this)
*/
#define WRITE0_OFFSET           0

#define XAC_ERR_OFFSET          0x2000
#define XAC_CTL0_OFFSET         0x10000
#define XAC_CTL1_OFFSET         0x11000
#define XAC_ELUA_OFFSET         0x12000
#define XAC_ELLA_OFFSET         0x13000
#define XAC_ELE_OFFSET          0x14000

#define XBC_ERR_OFFSET          0x42000
#define XBC_CTL0_OFFSET         0x50000
#define XBC_CTL1_OFFSET         0x51000
#define XBC_ELUA_OFFSET         0x52000
#define XBC_ELLA_OFFSET         0x53000
#define XBC_ELE_OFFSET          0x54000

#define XBOX_NREG               13

struct xbox_softc {
       int             sc_key;         /* this xbox's unique key */
};

/* autoconfiguration driver */
int     xbox_match(device_t, cfdata_t, void *);
void    xbox_attach(device_t, device_t, void *);
int     xbox_print(void *, const char *);

CFATTACH_DECL_NEW(xbox, sizeof(struct xbox_softc),
   xbox_match, xbox_attach, NULL, NULL);

int
xbox_print(void *args, const char *busname)
{
       struct xbox_attach_args *xa = args;

       if (busname)
               aprint_normal("%s at %s", xa->xa_name, busname);
       return (UNCONF);
}

int
xbox_match(device_t parent, cfdata_t cf, void *aux)
{
       struct sbus_attach_args *sa = aux;

       return (strcmp("SUNW,xbox", sa->sa_name) == 0);
}

/*
* Attach an Xbox.
*/
void
xbox_attach(device_t parent, device_t self, void *aux)
{
       struct xbox_softc *sc = device_private(self);
       struct sbus_attach_args *sa = aux;
       int node = sa->sa_node;
       struct xbox_attach_args xa;
       char *cp;

       sc->sc_key = prom_getpropint(node, "write0-key", -1);

       cp = prom_getpropstring(node, "model");
       printf(": model %s", cp);

       cp = prom_getpropstring(node, "child-present");
       if (strcmp(cp, "true") != 0) {
               printf(": no sbus devices\n");
               return;
       }

       printf("\n");

       /*
        * Now pretend to be another Sbus.
        */
       memset(&xa, 0, sizeof xa);
       xa.xa_name = "sbus";
       xa.xa_node = node;
       xa.xa_bustag = sa->sa_bustag;
       xa.xa_dmatag = sa->sa_dmatag;

       (void) config_found(self, (void *)&xa, xbox_print,
           CFARGS(.devhandle = device_handle(self)));
}