qemu-e2k/hw/ppc/spapr_vio.c
Markus Armbruster 3c6ef471ee sysbus: Convert to sysbus_realize() etc. with Coccinelle
Convert from qdev_realize(), qdev_realize_and_unref() with null @bus
argument to sysbus_realize(), sysbus_realize_and_unref().

Coccinelle script:

    @@
    expression dev, errp;
    @@
    -    qdev_realize(DEVICE(dev), NULL, errp);
    +    sysbus_realize(SYS_BUS_DEVICE(dev), errp);

    @@
    expression sysbus_dev, dev, errp;
    @@
    +    sysbus_dev = SYS_BUS_DEVICE(dev);
    -    qdev_realize_and_unref(dev, NULL, errp);
    +    sysbus_realize_and_unref(sysbus_dev, errp);
    -    sysbus_dev = SYS_BUS_DEVICE(dev);

    @@
    expression sysbus_dev, dev, errp;
    expression expr;
    @@
         sysbus_dev = SYS_BUS_DEVICE(dev);
         ... when != dev = expr;
    -    qdev_realize_and_unref(dev, NULL, errp);
    +    sysbus_realize_and_unref(sysbus_dev, errp);

    @@
    expression dev, errp;
    @@
    -    qdev_realize_and_unref(DEVICE(dev), NULL, errp);
    +    sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), errp);

    @@
    expression dev, errp;
    @@
    -    qdev_realize_and_unref(dev, NULL, errp);
    +    sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), errp);

Whitespace changes minimized manually.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200610053247.1583243-46-armbru@redhat.com>
[Conflicts in hw/misc/empty_slot.c and hw/sparc/leon3.c resolved]
2020-06-15 22:05:28 +02:00

745 lines
20 KiB
C

/*
* QEMU sPAPR VIO code
*
* Copyright (c) 2010 David Gibson, IBM Corporation <dwg@au1.ibm.com>
* Based on the s390 virtio bus code:
* Copyright (c) 2009 Alexander Graf <agraf@suse.de>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "qemu/error-report.h"
#include "qapi/error.h"
#include "qapi/visitor.h"
#include "qemu/log.h"
#include "hw/loader.h"
#include "elf.h"
#include "hw/sysbus.h"
#include "sysemu/kvm.h"
#include "sysemu/device_tree.h"
#include "kvm_ppc.h"
#include "migration/vmstate.h"
#include "sysemu/qtest.h"
#include "hw/ppc/spapr.h"
#include "hw/ppc/spapr_vio.h"
#include "hw/ppc/fdt.h"
#include "trace.h"
#include <libfdt.h>
#define SPAPR_VIO_REG_BASE 0x71000000
static char *spapr_vio_get_dev_name(DeviceState *qdev)
{
SpaprVioDevice *dev = VIO_SPAPR_DEVICE(qdev);
SpaprVioDeviceClass *pc = VIO_SPAPR_DEVICE_GET_CLASS(dev);
/* Device tree style name device@reg */
return g_strdup_printf("%s@%x", pc->dt_name, dev->reg);
}
static void spapr_vio_bus_class_init(ObjectClass *klass, void *data)
{
BusClass *k = BUS_CLASS(klass);
k->get_dev_path = spapr_vio_get_dev_name;
k->get_fw_dev_path = spapr_vio_get_dev_name;
}
static const TypeInfo spapr_vio_bus_info = {
.name = TYPE_SPAPR_VIO_BUS,
.parent = TYPE_BUS,
.class_init = spapr_vio_bus_class_init,
.instance_size = sizeof(SpaprVioBus),
};
SpaprVioDevice *spapr_vio_find_by_reg(SpaprVioBus *bus, uint32_t reg)
{
BusChild *kid;
SpaprVioDevice *dev = NULL;
QTAILQ_FOREACH(kid, &bus->bus.children, sibling) {
dev = (SpaprVioDevice *)kid->child;
if (dev->reg == reg) {
return dev;
}
}
return NULL;
}
static int vio_make_devnode(SpaprVioDevice *dev,
void *fdt)
{
SpaprVioDeviceClass *pc = VIO_SPAPR_DEVICE_GET_CLASS(dev);
int vdevice_off, node_off, ret;
char *dt_name;
const char *dt_compatible;
vdevice_off = fdt_path_offset(fdt, "/vdevice");
if (vdevice_off < 0) {
return vdevice_off;
}
dt_name = spapr_vio_get_dev_name(DEVICE(dev));
node_off = fdt_add_subnode(fdt, vdevice_off, dt_name);
g_free(dt_name);
if (node_off < 0) {
return node_off;
}
ret = fdt_setprop_cell(fdt, node_off, "reg", dev->reg);
if (ret < 0) {
return ret;
}
if (pc->dt_type) {
ret = fdt_setprop_string(fdt, node_off, "device_type",
pc->dt_type);
if (ret < 0) {
return ret;
}
}
if (pc->get_dt_compatible) {
dt_compatible = pc->get_dt_compatible(dev);
} else {
dt_compatible = pc->dt_compatible;
}
if (dt_compatible) {
ret = fdt_setprop_string(fdt, node_off, "compatible",
dt_compatible);
if (ret < 0) {
return ret;
}
}
if (dev->irq) {
uint32_t ints_prop[2];
spapr_dt_irq(ints_prop, dev->irq, false);
ret = fdt_setprop(fdt, node_off, "interrupts", ints_prop,
sizeof(ints_prop));
if (ret < 0) {
return ret;
}
}
ret = spapr_tcet_dma_dt(fdt, node_off, "ibm,my-dma-window", dev->tcet);
if (ret < 0) {
return ret;
}
if (pc->devnode) {
ret = (pc->devnode)(dev, fdt, node_off);
if (ret < 0) {
return ret;
}
}
return node_off;
}
/*
* CRQ handling
*/
static target_ulong h_reg_crq(PowerPCCPU *cpu, SpaprMachineState *spapr,
target_ulong opcode, target_ulong *args)
{
target_ulong reg = args[0];
target_ulong queue_addr = args[1];
target_ulong queue_len = args[2];
SpaprVioDevice *dev = spapr_vio_find_by_reg(spapr->vio_bus, reg);
if (!dev) {
hcall_dprintf("Unit 0x" TARGET_FMT_lx " does not exist\n", reg);
return H_PARAMETER;
}
/* We can't grok a queue size bigger than 256M for now */
if (queue_len < 0x1000 || queue_len > 0x10000000) {
hcall_dprintf("Queue size too small or too big (0x" TARGET_FMT_lx
")\n", queue_len);
return H_PARAMETER;
}
/* Check queue alignment */
if (queue_addr & 0xfff) {
hcall_dprintf("Queue not aligned (0x" TARGET_FMT_lx ")\n", queue_addr);
return H_PARAMETER;
}
/* Check if device supports CRQs */
if (!dev->crq.SendFunc) {
hcall_dprintf("Device does not support CRQ\n");
return H_NOT_FOUND;
}
/* Already a queue ? */
if (dev->crq.qsize) {
hcall_dprintf("CRQ already registered\n");
return H_RESOURCE;
}
dev->crq.qladdr = queue_addr;
dev->crq.qsize = queue_len;
dev->crq.qnext = 0;
trace_spapr_vio_h_reg_crq(reg, queue_addr, queue_len);
return H_SUCCESS;
}
static target_ulong free_crq(SpaprVioDevice *dev)
{
dev->crq.qladdr = 0;
dev->crq.qsize = 0;
dev->crq.qnext = 0;
trace_spapr_vio_free_crq(dev->reg);
return H_SUCCESS;
}
static target_ulong h_free_crq(PowerPCCPU *cpu, SpaprMachineState *spapr,
target_ulong opcode, target_ulong *args)
{
target_ulong reg = args[0];
SpaprVioDevice *dev = spapr_vio_find_by_reg(spapr->vio_bus, reg);
if (!dev) {
hcall_dprintf("Unit 0x" TARGET_FMT_lx " does not exist\n", reg);
return H_PARAMETER;
}
return free_crq(dev);
}
static target_ulong h_send_crq(PowerPCCPU *cpu, SpaprMachineState *spapr,
target_ulong opcode, target_ulong *args)
{
target_ulong reg = args[0];
target_ulong msg_hi = args[1];
target_ulong msg_lo = args[2];
SpaprVioDevice *dev = spapr_vio_find_by_reg(spapr->vio_bus, reg);
uint64_t crq_mangle[2];
if (!dev) {
hcall_dprintf("Unit 0x" TARGET_FMT_lx " does not exist\n", reg);
return H_PARAMETER;
}
crq_mangle[0] = cpu_to_be64(msg_hi);
crq_mangle[1] = cpu_to_be64(msg_lo);
if (dev->crq.SendFunc) {
return dev->crq.SendFunc(dev, (uint8_t *)crq_mangle);
}
return H_HARDWARE;
}
static target_ulong h_enable_crq(PowerPCCPU *cpu, SpaprMachineState *spapr,
target_ulong opcode, target_ulong *args)
{
target_ulong reg = args[0];
SpaprVioDevice *dev = spapr_vio_find_by_reg(spapr->vio_bus, reg);
if (!dev) {
hcall_dprintf("Unit 0x" TARGET_FMT_lx " does not exist\n", reg);
return H_PARAMETER;
}
return 0;
}
/* Returns negative error, 0 success, or positive: queue full */
int spapr_vio_send_crq(SpaprVioDevice *dev, uint8_t *crq)
{
int rc;
uint8_t byte;
if (!dev->crq.qsize) {
error_report("spapr_vio_send_creq on uninitialized queue");
return -1;
}
/* Maybe do a fast path for KVM just writing to the pages */
rc = spapr_vio_dma_read(dev, dev->crq.qladdr + dev->crq.qnext, &byte, 1);
if (rc) {
return rc;
}
if (byte != 0) {
return 1;
}
rc = spapr_vio_dma_write(dev, dev->crq.qladdr + dev->crq.qnext + 8,
&crq[8], 8);
if (rc) {
return rc;
}
kvmppc_eieio();
rc = spapr_vio_dma_write(dev, dev->crq.qladdr + dev->crq.qnext, crq, 8);
if (rc) {
return rc;
}
dev->crq.qnext = (dev->crq.qnext + 16) % dev->crq.qsize;
if (dev->signal_state & 1) {
spapr_vio_irq_pulse(dev);
}
return 0;
}
/* "quiesce" handling */
static void spapr_vio_quiesce_one(SpaprVioDevice *dev)
{
if (dev->tcet) {
device_legacy_reset(DEVICE(dev->tcet));
}
free_crq(dev);
}
void spapr_vio_set_bypass(SpaprVioDevice *dev, bool bypass)
{
if (!dev->tcet) {
return;
}
memory_region_set_enabled(&dev->mrbypass, bypass);
memory_region_set_enabled(spapr_tce_get_iommu(dev->tcet), !bypass);
dev->tcet->bypass = bypass;
}
static void rtas_set_tce_bypass(PowerPCCPU *cpu, SpaprMachineState *spapr,
uint32_t token,
uint32_t nargs, target_ulong args,
uint32_t nret, target_ulong rets)
{
SpaprVioBus *bus = spapr->vio_bus;
SpaprVioDevice *dev;
uint32_t unit, enable;
if (nargs != 2) {
rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
return;
}
unit = rtas_ld(args, 0);
enable = rtas_ld(args, 1);
dev = spapr_vio_find_by_reg(bus, unit);
if (!dev) {
rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
return;
}
if (!dev->tcet) {
rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
return;
}
spapr_vio_set_bypass(dev, !!enable);
rtas_st(rets, 0, RTAS_OUT_SUCCESS);
}
static void rtas_quiesce(PowerPCCPU *cpu, SpaprMachineState *spapr,
uint32_t token,
uint32_t nargs, target_ulong args,
uint32_t nret, target_ulong rets)
{
SpaprVioBus *bus = spapr->vio_bus;
BusChild *kid;
SpaprVioDevice *dev = NULL;
if (nargs != 0) {
rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
return;
}
QTAILQ_FOREACH(kid, &bus->bus.children, sibling) {
dev = (SpaprVioDevice *)kid->child;
spapr_vio_quiesce_one(dev);
}
rtas_st(rets, 0, RTAS_OUT_SUCCESS);
}
static SpaprVioDevice *reg_conflict(SpaprVioDevice *dev)
{
SpaprVioBus *bus = SPAPR_VIO_BUS(dev->qdev.parent_bus);
BusChild *kid;
SpaprVioDevice *other;
/*
* Check for a device other than the given one which is already
* using the requested address. We have to open code this because
* the given dev might already be in the list.
*/
QTAILQ_FOREACH(kid, &bus->bus.children, sibling) {
other = VIO_SPAPR_DEVICE(kid->child);
if (other != dev && other->reg == dev->reg) {
return other;
}
}
return 0;
}
static void spapr_vio_busdev_reset(DeviceState *qdev)
{
SpaprVioDevice *dev = VIO_SPAPR_DEVICE(qdev);
SpaprVioDeviceClass *pc = VIO_SPAPR_DEVICE_GET_CLASS(dev);
/* Shut down the request queue and TCEs if necessary */
spapr_vio_quiesce_one(dev);
dev->signal_state = 0;
spapr_vio_set_bypass(dev, false);
if (pc->reset) {
pc->reset(dev);
}
}
/*
* The register property of a VIO device is defined in livirt using
* 0x1000 as a base register number plus a 0x1000 increment. For the
* VIO tty device, the base number is changed to 0x30000000. QEMU uses
* a base register number of 0x71000000 and then a simple increment.
*
* The formula below tries to compute a unique index number from the
* register value that will be used to define the IRQ number of the
* VIO device.
*
* A maximum of 256 VIO devices is covered. Collisions are possible
* but they will be detected when the IRQ is claimed.
*/
static inline uint32_t spapr_vio_reg_to_irq(uint32_t reg)
{
uint32_t irq;
if (reg >= SPAPR_VIO_REG_BASE) {
/*
* VIO device register values when allocated by QEMU. For
* these, we simply mask the high bits to fit the overall
* range: [0x00 - 0xff].
*
* The nvram VIO device (reg=0x71000000) is a static device of
* the pseries machine and so is always allocated by QEMU. Its
* IRQ number is 0x0.
*/
irq = reg & 0xff;
} else if (reg >= 0x30000000) {
/*
* VIO tty devices register values, when allocated by livirt,
* are mapped in range [0xf0 - 0xff], gives us a maximum of 16
* vtys.
*/
irq = 0xf0 | ((reg >> 12) & 0xf);
} else {
/*
* Other VIO devices register values, when allocated by
* livirt, should be mapped in range [0x00 - 0xef]. Conflicts
* will be detected when IRQ is claimed.
*/
irq = (reg >> 12) & 0xff;
}
return SPAPR_IRQ_VIO | irq;
}
static void spapr_vio_busdev_realize(DeviceState *qdev, Error **errp)
{
SpaprMachineState *spapr = SPAPR_MACHINE(qdev_get_machine());
SpaprVioDevice *dev = (SpaprVioDevice *)qdev;
SpaprVioDeviceClass *pc = VIO_SPAPR_DEVICE_GET_CLASS(dev);
char *id;
Error *local_err = NULL;
if (dev->reg != -1) {
/*
* Explicitly assigned address, just verify that no-one else
* is using it. other mechanism). We have to open code this
* rather than using spapr_vio_find_by_reg() because sdev
* itself is already in the list.
*/
SpaprVioDevice *other = reg_conflict(dev);
if (other) {
error_setg(errp, "%s and %s devices conflict at address %#x",
object_get_typename(OBJECT(qdev)),
object_get_typename(OBJECT(&other->qdev)),
dev->reg);
return;
}
} else {
/* Need to assign an address */
SpaprVioBus *bus = SPAPR_VIO_BUS(dev->qdev.parent_bus);
do {
dev->reg = bus->next_reg++;
} while (reg_conflict(dev));
}
/* Don't overwrite ids assigned on the command line */
if (!dev->qdev.id) {
id = spapr_vio_get_dev_name(DEVICE(dev));
dev->qdev.id = id;
}
dev->irq = spapr_vio_reg_to_irq(dev->reg);
if (SPAPR_MACHINE_GET_CLASS(spapr)->legacy_irq_allocation) {
dev->irq = spapr_irq_findone(spapr, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
}
spapr_irq_claim(spapr, dev->irq, false, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
if (pc->rtce_window_size) {
uint32_t liobn = SPAPR_VIO_LIOBN(dev->reg);
memory_region_init(&dev->mrroot, OBJECT(dev), "iommu-spapr-root",
ram_size);
memory_region_init_alias(&dev->mrbypass, OBJECT(dev),
"iommu-spapr-bypass", get_system_memory(),
0, ram_size);
memory_region_add_subregion_overlap(&dev->mrroot, 0, &dev->mrbypass, 1);
address_space_init(&dev->as, &dev->mrroot, qdev->id);
dev->tcet = spapr_tce_new_table(qdev, liobn);
spapr_tce_table_enable(dev->tcet, SPAPR_TCE_PAGE_SHIFT, 0,
pc->rtce_window_size >> SPAPR_TCE_PAGE_SHIFT);
dev->tcet->vdev = dev;
memory_region_add_subregion_overlap(&dev->mrroot, 0,
spapr_tce_get_iommu(dev->tcet), 2);
}
pc->realize(dev, errp);
}
static target_ulong h_vio_signal(PowerPCCPU *cpu, SpaprMachineState *spapr,
target_ulong opcode,
target_ulong *args)
{
target_ulong reg = args[0];
target_ulong mode = args[1];
SpaprVioDevice *dev = spapr_vio_find_by_reg(spapr->vio_bus, reg);
SpaprVioDeviceClass *pc;
if (!dev) {
return H_PARAMETER;
}
pc = VIO_SPAPR_DEVICE_GET_CLASS(dev);
if (mode & ~pc->signal_mask) {
return H_PARAMETER;
}
dev->signal_state = mode;
return H_SUCCESS;
}
SpaprVioBus *spapr_vio_bus_init(void)
{
SpaprVioBus *bus;
BusState *qbus;
DeviceState *dev;
/* Create bridge device */
dev = qdev_new(TYPE_SPAPR_VIO_BRIDGE);
sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
/* Create bus on bridge device */
qbus = qbus_create(TYPE_SPAPR_VIO_BUS, dev, "spapr-vio");
bus = SPAPR_VIO_BUS(qbus);
bus->next_reg = SPAPR_VIO_REG_BASE;
/* hcall-vio */
spapr_register_hypercall(H_VIO_SIGNAL, h_vio_signal);
/* hcall-crq */
spapr_register_hypercall(H_REG_CRQ, h_reg_crq);
spapr_register_hypercall(H_FREE_CRQ, h_free_crq);
spapr_register_hypercall(H_SEND_CRQ, h_send_crq);
spapr_register_hypercall(H_ENABLE_CRQ, h_enable_crq);
/* RTAS calls */
spapr_rtas_register(RTAS_IBM_SET_TCE_BYPASS, "ibm,set-tce-bypass",
rtas_set_tce_bypass);
spapr_rtas_register(RTAS_QUIESCE, "quiesce", rtas_quiesce);
return bus;
}
static void spapr_vio_bridge_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->fw_name = "vdevice";
}
static const TypeInfo spapr_vio_bridge_info = {
.name = TYPE_SPAPR_VIO_BRIDGE,
.parent = TYPE_SYS_BUS_DEVICE,
.class_init = spapr_vio_bridge_class_init,
};
const VMStateDescription vmstate_spapr_vio = {
.name = "spapr_vio",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
/* Sanity check */
VMSTATE_UINT32_EQUAL(reg, SpaprVioDevice, NULL),
VMSTATE_UINT32_EQUAL(irq, SpaprVioDevice, NULL),
/* General VIO device state */
VMSTATE_UINT64(signal_state, SpaprVioDevice),
VMSTATE_UINT64(crq.qladdr, SpaprVioDevice),
VMSTATE_UINT32(crq.qsize, SpaprVioDevice),
VMSTATE_UINT32(crq.qnext, SpaprVioDevice),
VMSTATE_END_OF_LIST()
},
};
static void vio_spapr_device_class_init(ObjectClass *klass, void *data)
{
DeviceClass *k = DEVICE_CLASS(klass);
k->realize = spapr_vio_busdev_realize;
k->reset = spapr_vio_busdev_reset;
k->bus_type = TYPE_SPAPR_VIO_BUS;
}
static const TypeInfo spapr_vio_type_info = {
.name = TYPE_VIO_SPAPR_DEVICE,
.parent = TYPE_DEVICE,
.instance_size = sizeof(SpaprVioDevice),
.abstract = true,
.class_size = sizeof(SpaprVioDeviceClass),
.class_init = vio_spapr_device_class_init,
};
static void spapr_vio_register_types(void)
{
type_register_static(&spapr_vio_bus_info);
type_register_static(&spapr_vio_bridge_info);
type_register_static(&spapr_vio_type_info);
}
type_init(spapr_vio_register_types)
static int compare_reg(const void *p1, const void *p2)
{
SpaprVioDevice const *dev1, *dev2;
dev1 = (SpaprVioDevice *)*(DeviceState **)p1;
dev2 = (SpaprVioDevice *)*(DeviceState **)p2;
if (dev1->reg < dev2->reg) {
return -1;
}
if (dev1->reg == dev2->reg) {
return 0;
}
/* dev1->reg > dev2->reg */
return 1;
}
void spapr_dt_vdevice(SpaprVioBus *bus, void *fdt)
{
DeviceState *qdev, **qdevs;
BusChild *kid;
int i, num, ret = 0;
int node;
_FDT(node = fdt_add_subnode(fdt, 0, "vdevice"));
_FDT(fdt_setprop_string(fdt, node, "device_type", "vdevice"));
_FDT(fdt_setprop_string(fdt, node, "compatible", "IBM,vdevice"));
_FDT(fdt_setprop_cell(fdt, node, "#address-cells", 1));
_FDT(fdt_setprop_cell(fdt, node, "#size-cells", 0));
_FDT(fdt_setprop_cell(fdt, node, "#interrupt-cells", 2));
_FDT(fdt_setprop(fdt, node, "interrupt-controller", NULL, 0));
/* Count qdevs on the bus list */
num = 0;
QTAILQ_FOREACH(kid, &bus->bus.children, sibling) {
num++;
}
/* Copy out into an array of pointers */
qdevs = g_new(DeviceState *, num);
num = 0;
QTAILQ_FOREACH(kid, &bus->bus.children, sibling) {
qdevs[num++] = kid->child;
}
/* Sort the array */
qsort(qdevs, num, sizeof(qdev), compare_reg);
/* Hack alert. Give the devices to libfdt in reverse order, we happen
* to know that will mean they are in forward order in the tree. */
for (i = num - 1; i >= 0; i--) {
SpaprVioDevice *dev = (SpaprVioDevice *)(qdevs[i]);
SpaprVioDeviceClass *vdc = VIO_SPAPR_DEVICE_GET_CLASS(dev);
ret = vio_make_devnode(dev, fdt);
if (ret < 0) {
error_report("Couldn't create device node /vdevice/%s@%"PRIx32,
vdc->dt_name, dev->reg);
exit(1);
}
}
g_free(qdevs);
}
gchar *spapr_vio_stdout_path(SpaprVioBus *bus)
{
SpaprVioDevice *dev;
char *name, *path;
dev = spapr_vty_get_default(bus);
if (!dev) {
return NULL;
}
name = spapr_vio_get_dev_name(DEVICE(dev));
path = g_strdup_printf("/vdevice/%s", name);
g_free(name);
return path;
}