/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2011 Nathan Whitehorn
 * All rights reserved.
 *
 * 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 AUTHOR 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 AUTHOR 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/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/malloc.h>
#include <sys/bus.h>
#include <sys/cpu.h>
#include <machine/bus.h>
#include <machine/intr_machdep.h>

#include <dev/ofw/openfirm.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>

#include <powerpc/pseries/plpar_iommu.h>

#include "iommu_if.h"

static int      vdevice_probe(device_t);
static int      vdevice_attach(device_t);
static const struct ofw_bus_devinfo *vdevice_get_devinfo(device_t dev,
    device_t child);
static int      vdevice_print_child(device_t dev, device_t child);
static struct resource_list *vdevice_get_resource_list(device_t, device_t);
static bus_dma_tag_t vdevice_get_dma_tag(device_t dev, device_t child);

/*
 * VDevice devinfo
 */
struct vdevice_devinfo {
        struct ofw_bus_devinfo mdi_obdinfo;
        struct resource_list mdi_resources;
        bus_dma_tag_t mdi_dma_tag;
};

static device_method_t vdevice_methods[] = {
        /* Device interface */
        DEVMETHOD(device_probe,         vdevice_probe),
        DEVMETHOD(device_attach,        vdevice_attach),

        /* Bus interface */
        DEVMETHOD(bus_add_child,        bus_generic_add_child),
        DEVMETHOD(bus_child_pnpinfo,    ofw_bus_gen_child_pnpinfo),
        DEVMETHOD(bus_print_child,      vdevice_print_child),
        DEVMETHOD(bus_setup_intr,       bus_generic_setup_intr),
        DEVMETHOD(bus_teardown_intr,    bus_generic_teardown_intr),
        DEVMETHOD(bus_alloc_resource,   bus_generic_rl_alloc_resource),
        DEVMETHOD(bus_release_resource, bus_generic_rl_release_resource),
        DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
        DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
        DEVMETHOD(bus_get_resource_list, vdevice_get_resource_list),

        /* ofw_bus interface */
        DEVMETHOD(ofw_bus_get_devinfo,  vdevice_get_devinfo),
        DEVMETHOD(ofw_bus_get_compat,   ofw_bus_gen_get_compat),
        DEVMETHOD(ofw_bus_get_model,    ofw_bus_gen_get_model),
        DEVMETHOD(ofw_bus_get_name,     ofw_bus_gen_get_name),
        DEVMETHOD(ofw_bus_get_node,     ofw_bus_gen_get_node),
        DEVMETHOD(ofw_bus_get_type,     ofw_bus_gen_get_type),

        /* IOMMU interface */
        DEVMETHOD(bus_get_dma_tag,      vdevice_get_dma_tag),
        DEVMETHOD(iommu_map,            phyp_iommu_map),
        DEVMETHOD(iommu_unmap,          phyp_iommu_unmap),

        DEVMETHOD_END
};

static driver_t vdevice_driver = {
        "vdevice",
        vdevice_methods,
        0
};

DRIVER_MODULE(vdevice, ofwbus, vdevice_driver, 0, 0);

static int 
vdevice_probe(device_t dev) 
{
        const char      *name;

        name = ofw_bus_get_name(dev);

        if (name == NULL || strcmp(name, "vdevice") != 0)
                return (ENXIO);

        if (!ofw_bus_is_compatible(dev, "IBM,vdevice"))
                return (ENXIO);

        device_set_desc(dev, "POWER Hypervisor Virtual Device Root");

        return (0);
}

static int 
vdevice_attach(device_t dev) 
{
        phandle_t root, child;
        device_t cdev;
        struct vdevice_devinfo *dinfo;

        root = ofw_bus_get_node(dev);

        /* The XICP (root PIC) will handle all our interrupts */
        powerpc_register_pic(root_pic, OF_xref_from_node(root),
            1 << 24 /* 24-bit XIRR field */, 1 /* Number of IPIs */, FALSE);

        for (child = OF_child(root); child != 0; child = OF_peer(child)) {
                dinfo = malloc(sizeof(*dinfo), M_DEVBUF, M_WAITOK | M_ZERO);

                if (ofw_bus_gen_setup_devinfo(&dinfo->mdi_obdinfo,
                    child) != 0) {
                        free(dinfo, M_DEVBUF);
                        continue;
                }
                resource_list_init(&dinfo->mdi_resources);

                ofw_bus_intr_to_rl(dev, child, &dinfo->mdi_resources, NULL);

                cdev = device_add_child(dev, NULL, DEVICE_UNIT_ANY);
                if (cdev == NULL) {
                        device_printf(dev, "<%s>: device_add_child failed\n",
                            dinfo->mdi_obdinfo.obd_name);
                        ofw_bus_gen_destroy_devinfo(&dinfo->mdi_obdinfo);
                        free(dinfo, M_DEVBUF);
                        continue;
                }
                device_set_ivars(cdev, dinfo);
        }

        bus_attach_children(dev);
        return (0);
}

static const struct ofw_bus_devinfo *
vdevice_get_devinfo(device_t dev, device_t child) 
{
        return (device_get_ivars(child));       
}

static int
vdevice_print_child(device_t dev, device_t child)
{
        struct vdevice_devinfo *dinfo;
        struct resource_list *rl;
        int retval = 0;

        dinfo = device_get_ivars(child);
        rl = &dinfo->mdi_resources;

        retval += bus_print_child_header(dev, child);

        retval += resource_list_print_type(rl, "irq", SYS_RES_IRQ, "%jd");

        retval += bus_print_child_footer(dev, child);

        return (retval);
}

static struct resource_list *
vdevice_get_resource_list (device_t dev, device_t child)
{
        struct vdevice_devinfo *dinfo;

        dinfo = device_get_ivars(child);
        return (&dinfo->mdi_resources);
}

static bus_dma_tag_t
vdevice_get_dma_tag(device_t dev, device_t child)
{
        struct vdevice_devinfo *dinfo;
        while (child != NULL && device_get_parent(child) != dev)
                child = device_get_parent(child);
        dinfo = device_get_ivars(child);

        if (dinfo->mdi_dma_tag == NULL) {
                bus_dma_tag_create(bus_get_dma_tag(dev),
                    1, 0, BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR,
                    NULL, NULL, BUS_SPACE_MAXSIZE, BUS_SPACE_UNRESTRICTED,
                    BUS_SPACE_MAXSIZE, 0, NULL, NULL, &dinfo->mdi_dma_tag);
                phyp_iommu_set_dma_tag(dev, child, dinfo->mdi_dma_tag);
        }

        return (dinfo->mdi_dma_tag);
}