qemu-e2k/hw/misc/unimp.c

100 lines
2.8 KiB
C

/* "Unimplemented" device
*
* This is a dummy device which accepts and logs all accesses.
* It's useful for stubbing out regions of an SoC or board
* map which correspond to devices that have not yet been
* implemented. This is often sufficient to placate initial
* guest device driver probing such that the system will
* come up.
*
* Copyright Linaro Limited, 2017
* Written by Peter Maydell
*/
#include "qemu/osdep.h"
#include "hw/sysbus.h"
#include "hw/misc/unimp.h"
#include "qemu/log.h"
#include "qemu/module.h"
#include "qapi/error.h"
static uint64_t unimp_read(void *opaque, hwaddr offset, unsigned size)
{
UnimplementedDeviceState *s = UNIMPLEMENTED_DEVICE(opaque);
qemu_log_mask(LOG_UNIMP, "%s: unimplemented device read "
"(size %d, offset 0x%0*" HWADDR_PRIx ")\n",
s->name, size, s->offset_fmt_width, offset);
return 0;
}
static void unimp_write(void *opaque, hwaddr offset,
uint64_t value, unsigned size)
{
UnimplementedDeviceState *s = UNIMPLEMENTED_DEVICE(opaque);
qemu_log_mask(LOG_UNIMP, "%s: unimplemented device write "
"(size %d, offset 0x%0*" HWADDR_PRIx
", value 0x%0*" PRIx64 ")\n",
s->name, size, s->offset_fmt_width, offset, size << 1, value);
}
static const MemoryRegionOps unimp_ops = {
.read = unimp_read,
.write = unimp_write,
.impl.min_access_size = 1,
.impl.max_access_size = 8,
.valid.min_access_size = 1,
.valid.max_access_size = 8,
.endianness = DEVICE_NATIVE_ENDIAN,
};
static void unimp_realize(DeviceState *dev, Error **errp)
{
UnimplementedDeviceState *s = UNIMPLEMENTED_DEVICE(dev);
if (s->size == 0) {
error_setg(errp, "property 'size' not specified or zero");
return;
}
if (s->name == NULL) {
error_setg(errp, "property 'name' not specified");
return;
}
s->offset_fmt_width = DIV_ROUND_UP(64 - clz64(s->size - 1), 4);
memory_region_init_io(&s->iomem, OBJECT(s), &unimp_ops, s,
s->name, s->size);
sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem);
}
static Property unimp_properties[] = {
DEFINE_PROP_UINT64("size", UnimplementedDeviceState, size, 0),
DEFINE_PROP_STRING("name", UnimplementedDeviceState, name),
DEFINE_PROP_END_OF_LIST(),
};
static void unimp_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->realize = unimp_realize;
device_class_set_props(dc, unimp_properties);
}
static const TypeInfo unimp_info = {
.name = TYPE_UNIMPLEMENTED_DEVICE,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(UnimplementedDeviceState),
.class_init = unimp_class_init,
};
static void unimp_register_types(void)
{
type_register_static(&unimp_info);
}
type_init(unimp_register_types)