Archipelago » qemu

/*

 * QEMU Synchronous Serial Interface support

 *

 * Copyright (c) 2009 CodeSourcery.

 * Copyright (c) 2012 Peter A.G. Crosthwaite (peter.crosthwaite@petalogix.com)

 * Copyright (c) 2012 PetaLogix Pty Ltd.

 * Written by Paul Brook

 *

 * This code is licensed under the GNU GPL v2.

 *

 * Contributions after 2012-01-13 are licensed under the terms of the

 * GNU GPL, version 2 or (at your option) any later version.

 */

#include "ssi.h"

struct SSIBus {

    BusState qbus;

};

#define TYPE_SSI_BUS "SSI"

#define SSI_BUS(obj) OBJECT_CHECK(SSIBus, (obj), TYPE_SSI_BUS)

static const TypeInfo ssi_bus_info = {

    .name = TYPE_SSI_BUS,

    .parent = TYPE_BUS,

    .instance_size = sizeof(SSIBus),

};

static void ssi_cs_default(void *opaque, int n, int level)

{

    SSISlave *s = SSI_SLAVE(opaque);

    bool cs = !!level;

    assert(n == 0);

    if (s->cs != cs) {

        SSISlaveClass *ssc = SSI_SLAVE_GET_CLASS(s);

        if (ssc->set_cs) {

            ssc->set_cs(s, cs);

        }

    }

    s->cs = cs;

}

static uint32_t ssi_transfer_raw_default(SSISlave *dev, uint32_t val)

{

    SSISlaveClass *ssc = SSI_SLAVE_GET_CLASS(dev);

    if ((dev->cs && ssc->cs_polarity == SSI_CS_HIGH) ||

            (!dev->cs && ssc->cs_polarity == SSI_CS_LOW) ||

            ssc->cs_polarity == SSI_CS_NONE) {

        return ssc->transfer(dev, val);

    }

    return 0;

}

static int ssi_slave_init(DeviceState *dev)

{

    SSISlave *s = SSI_SLAVE(dev);

    SSISlaveClass *ssc = SSI_SLAVE_GET_CLASS(s);

    if (ssc->transfer_raw == ssi_transfer_raw_default &&

            ssc->cs_polarity != SSI_CS_NONE) {

        qdev_init_gpio_in(&s->qdev, ssi_cs_default, 1);

    }

    return ssc->init(s);

}

static void ssi_slave_class_init(ObjectClass *klass, void *data)

{

    SSISlaveClass *ssc = SSI_SLAVE_CLASS(klass);

    DeviceClass *dc = DEVICE_CLASS(klass);

    dc->init = ssi_slave_init;

    dc->bus_type = TYPE_SSI_BUS;

    if (!ssc->transfer_raw) {

        ssc->transfer_raw = ssi_transfer_raw_default;

    }

}

static const TypeInfo ssi_slave_info = {

    .name = TYPE_SSI_SLAVE,

    .parent = TYPE_DEVICE,

    .class_init = ssi_slave_class_init,

    .class_size = sizeof(SSISlaveClass),

    .abstract = true,

};

DeviceState *ssi_create_slave_no_init(SSIBus *bus, const char *name)

{

    return qdev_create(&bus->qbus, name);

}

DeviceState *ssi_create_slave(SSIBus *bus, const char *name)

{

    DeviceState *dev = ssi_create_slave_no_init(bus, name);

    qdev_init_nofail(dev);

    return dev;

}

SSIBus *ssi_create_bus(DeviceState *parent, const char *name)

{

    BusState *bus;

    bus = qbus_create(TYPE_SSI_BUS, parent, name);

    return FROM_QBUS(SSIBus, bus);

}

uint32_t ssi_transfer(SSIBus *bus, uint32_t val)

{

    BusChild *kid;

    SSISlaveClass *ssc;

    uint32_t r = 0;

    QTAILQ_FOREACH(kid, &bus->qbus.children, sibling) {

        SSISlave *slave = SSI_SLAVE(kid->child);

        ssc = SSI_SLAVE_GET_CLASS(slave);

        r |= ssc->transfer_raw(slave, val);

    }

    return r;

}

const VMStateDescription vmstate_ssi_slave = {

    .name = "SSISlave",

    .version_id = 1,

    .minimum_version_id = 1,

    .minimum_version_id_old = 1,

    .fields      = (VMStateField[]) {

        VMSTATE_BOOL(cs, SSISlave),

        VMSTATE_END_OF_LIST()

    }

};

static void ssi_slave_register_types(void)

{

    type_register_static(&ssi_bus_info);

    type_register_static(&ssi_slave_info);

}

type_init(ssi_slave_register_types)

typedef struct SSIAutoConnectArg {

    qemu_irq **cs_linep;

    SSIBus *bus;

} SSIAutoConnectArg;

static int ssi_auto_connect_slave(Object *child, void *opaque)

{

    SSIAutoConnectArg *arg = opaque;

    SSISlave *dev = (SSISlave *)object_dynamic_cast(child, TYPE_SSI_SLAVE);

    qemu_irq cs_line;

    if (!dev) {

        return 0;

    }

    cs_line = qdev_get_gpio_in(DEVICE(dev), 0);

    qdev_set_parent_bus(DEVICE(dev), &arg->bus->qbus);

    **arg->cs_linep = cs_line;

    (*arg->cs_linep)++;

    return 0;

}

void ssi_auto_connect_slaves(DeviceState *parent, qemu_irq *cs_line,

                             SSIBus *bus)

{

    SSIAutoConnectArg arg = {

        .cs_linep = &cs_line,

        .bus = bus

    };

    object_child_foreach(OBJECT(parent), ssi_auto_connect_slave, &arg);

}