Archipelago » qemu

/*

 * QEMU Empty Slot

 *

 * The empty_slot device emulates known to a bus but not connected devices.

 *

 * Copyright (c) 2010 Artyom Tarasenko

 *

 * This code is licensed under the GNU GPL v2 or (at your option) any later

 * version.

 */

#include "hw.h"

#include "sysbus.h"

#include "empty_slot.h"

//#define DEBUG_EMPTY_SLOT

#ifdef DEBUG_EMPTY_SLOT

#define DPRINTF(fmt, ...)                                       \

    do { printf("empty_slot: " fmt , ## __VA_ARGS__); } while (0)

#else

#define DPRINTF(fmt, ...) do {} while (0)

#endif

typedef struct EmptySlot {

    SysBusDevice busdev;

    MemoryRegion iomem;

    uint64_t size;

} EmptySlot;

static uint64_t empty_slot_read(void *opaque, target_phys_addr_t addr,

                                unsigned size)

{

    DPRINTF("read from " TARGET_FMT_plx "\n", addr);

    return 0;

}

static void empty_slot_write(void *opaque, target_phys_addr_t addr,

                             uint64_t val, unsigned size)

{

    DPRINTF("write 0x%x to " TARGET_FMT_plx "\n", (unsigned)val, addr);

}

static const MemoryRegionOps empty_slot_ops = {

    .read = empty_slot_read,

    .write = empty_slot_write,

    .endianness = DEVICE_NATIVE_ENDIAN,

};

void empty_slot_init(target_phys_addr_t addr, uint64_t slot_size)

{

    if (slot_size > 0) {

        /* Only empty slots larger than 0 byte need handling. */

        DeviceState *dev;

        SysBusDevice *s;

        EmptySlot *e;

        dev = qdev_create(NULL, "empty_slot");

        s = sysbus_from_qdev(dev);

        e = FROM_SYSBUS(EmptySlot, s);

        e->size = slot_size;

        qdev_init_nofail(dev);

        sysbus_mmio_map(s, 0, addr);

    }

}

static int empty_slot_init1(SysBusDevice *dev)

{

    EmptySlot *s = FROM_SYSBUS(EmptySlot, dev);

    memory_region_init_io(&s->iomem, &empty_slot_ops, s,

                          "empty-slot", s->size);

    sysbus_init_mmio(dev, &s->iomem);

    return 0;

}

static SysBusDeviceInfo empty_slot_info = {

    .init = empty_slot_init1,

    .qdev.name  = "empty_slot",

    .qdev.size  = sizeof(EmptySlot),

};

static void empty_slot_register_devices(void)

{

    sysbus_register_withprop(&empty_slot_info);

}

device_init(empty_slot_register_devices);