aboutsummaryrefslogtreecommitdiff
path: root/hw/ppc/spapr_vio.c
blob: b59452bcd62c34e41ea6081045c8713284d48374 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
/*
 * 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 2.1 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 "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_cold_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 libvirt 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 libvirt,
         * 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
         * libvirt, 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;

    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) {
        int irq = spapr_irq_findone(spapr, errp);

        if (irq < 0) {
            return;
        }
        dev->irq = irq;
    }

    if (spapr_irq_claim(spapr, dev->irq, false, errp) < 0) {
        return;
    }

    if (pc->rtce_window_size) {
        uint32_t liobn = SPAPR_VIO_LIOBN(dev->reg);

        memory_region_init(&dev->mrroot, OBJECT(dev), "iommu-spapr-root",
                           MACHINE(spapr)->ram_size);
        memory_region_init_alias(&dev->mrbypass, OBJECT(dev),
                                 "iommu-spapr-bypass", get_system_memory(),
                                 0, MACHINE(spapr)->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;
}