summaryrefslogtreecommitdiff
path: root/hw/pci-host/q35.c
blob: 344f77b10cd2e7ee7d14cef5cf9e6a07e1f39d9c (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
/*
 * QEMU MCH/ICH9 PCI Bridge Emulation
 *
 * Copyright (c) 2006 Fabrice Bellard
 * Copyright (c) 2009, 2010, 2011
 *               Isaku Yamahata <yamahata at valinux co jp>
 *               VA Linux Systems Japan K.K.
 * Copyright (C) 2012 Jason Baron <jbaron@redhat.com>
 *
 * This is based on piix.c, but heavily modified.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#include "qemu/osdep.h"
#include "hw/hw.h"
#include "hw/pci-host/q35.h"
#include "qapi/error.h"
#include "qapi/visitor.h"

/****************************************************************************
 * Q35 host
 */

static void q35_host_realize(DeviceState *dev, Error **errp)
{
    PCIHostState *pci = PCI_HOST_BRIDGE(dev);
    Q35PCIHost *s = Q35_HOST_DEVICE(dev);
    SysBusDevice *sbd = SYS_BUS_DEVICE(dev);

    sysbus_add_io(sbd, MCH_HOST_BRIDGE_CONFIG_ADDR, &pci->conf_mem);
    sysbus_init_ioports(sbd, MCH_HOST_BRIDGE_CONFIG_ADDR, 4);

    sysbus_add_io(sbd, MCH_HOST_BRIDGE_CONFIG_DATA, &pci->data_mem);
    sysbus_init_ioports(sbd, MCH_HOST_BRIDGE_CONFIG_DATA, 4);

    pci->bus = pci_bus_new(DEVICE(s), "pcie.0",
                           s->mch.pci_address_space, s->mch.address_space_io,
                           0, TYPE_PCIE_BUS);
    PC_MACHINE(qdev_get_machine())->bus = pci->bus;
    qdev_set_parent_bus(DEVICE(&s->mch), BUS(pci->bus));
    qdev_init_nofail(DEVICE(&s->mch));
}

static const char *q35_host_root_bus_path(PCIHostState *host_bridge,
                                          PCIBus *rootbus)
{
    Q35PCIHost *s = Q35_HOST_DEVICE(host_bridge);

     /* For backwards compat with old device paths */
    if (s->mch.short_root_bus) {
        return "0000";
    }
    return "0000:00";
}

static void q35_host_get_pci_hole_start(Object *obj, Visitor *v,
                                        const char *name, void *opaque,
                                        Error **errp)
{
    Q35PCIHost *s = Q35_HOST_DEVICE(obj);
    uint64_t val64;
    uint32_t value;

    val64 = range_is_empty(&s->mch.pci_hole)
        ? 0 : range_lob(&s->mch.pci_hole);
    value = val64;
    assert(value == val64);
    visit_type_uint32(v, name, &value, errp);
}

static void q35_host_get_pci_hole_end(Object *obj, Visitor *v,
                                      const char *name, void *opaque,
                                      Error **errp)
{
    Q35PCIHost *s = Q35_HOST_DEVICE(obj);
    uint64_t val64;
    uint32_t value;

    val64 = range_is_empty(&s->mch.pci_hole)
        ? 0 : range_upb(&s->mch.pci_hole) + 1;
    value = val64;
    assert(value == val64);
    visit_type_uint32(v, name, &value, errp);
}

static void q35_host_get_pci_hole64_start(Object *obj, Visitor *v,
                                          const char *name, void *opaque,
                                          Error **errp)
{
    PCIHostState *h = PCI_HOST_BRIDGE(obj);
    Range w64;
    uint64_t value;

    pci_bus_get_w64_range(h->bus, &w64);
    value = range_is_empty(&w64) ? 0 : range_lob(&w64);
    visit_type_uint64(v, name, &value, errp);
}

static void q35_host_get_pci_hole64_end(Object *obj, Visitor *v,
                                        const char *name, void *opaque,
                                        Error **errp)
{
    PCIHostState *h = PCI_HOST_BRIDGE(obj);
    Range w64;
    uint64_t value;

    pci_bus_get_w64_range(h->bus, &w64);
    value = range_is_empty(&w64) ? 0 : range_upb(&w64) + 1;
    visit_type_uint64(v, name, &value, errp);
}

static void q35_host_get_mmcfg_size(Object *obj, Visitor *v, const char *name,
                                    void *opaque, Error **errp)
{
    PCIExpressHost *e = PCIE_HOST_BRIDGE(obj);
    uint32_t value = e->size;

    visit_type_uint32(v, name, &value, errp);
}

static Property mch_props[] = {
    DEFINE_PROP_UINT64(PCIE_HOST_MCFG_BASE, Q35PCIHost, parent_obj.base_addr,
                        MCH_HOST_BRIDGE_PCIEXBAR_DEFAULT),
    DEFINE_PROP_SIZE(PCI_HOST_PROP_PCI_HOLE64_SIZE, Q35PCIHost,
                     mch.pci_hole64_size, DEFAULT_PCI_HOLE64_SIZE),
    DEFINE_PROP_UINT32("short_root_bus", Q35PCIHost, mch.short_root_bus, 0),
    DEFINE_PROP_SIZE(PCI_HOST_BELOW_4G_MEM_SIZE, Q35PCIHost,
                     mch.below_4g_mem_size, 0),
    DEFINE_PROP_SIZE(PCI_HOST_ABOVE_4G_MEM_SIZE, Q35PCIHost,
                     mch.above_4g_mem_size, 0),
    DEFINE_PROP_END_OF_LIST(),
};

static void q35_host_class_init(ObjectClass *klass, void *data)
{
    DeviceClass *dc = DEVICE_CLASS(klass);
    PCIHostBridgeClass *hc = PCI_HOST_BRIDGE_CLASS(klass);

    hc->root_bus_path = q35_host_root_bus_path;
    dc->realize = q35_host_realize;
    dc->props = mch_props;
    /* Reason: needs to be wired up by pc_q35_init */
    dc->cannot_instantiate_with_device_add_yet = true;
    set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
    dc->fw_name = "pci";
}

static void q35_host_initfn(Object *obj)
{
    Q35PCIHost *s = Q35_HOST_DEVICE(obj);
    PCIHostState *phb = PCI_HOST_BRIDGE(obj);

    memory_region_init_io(&phb->conf_mem, obj, &pci_host_conf_le_ops, phb,
                          "pci-conf-idx", 4);
    memory_region_init_io(&phb->data_mem, obj, &pci_host_data_le_ops, phb,
                          "pci-conf-data", 4);

    object_initialize(&s->mch, sizeof(s->mch), TYPE_MCH_PCI_DEVICE);
    object_property_add_child(OBJECT(s), "mch", OBJECT(&s->mch), NULL);
    qdev_prop_set_uint32(DEVICE(&s->mch), "addr", PCI_DEVFN(0, 0));
    qdev_prop_set_bit(DEVICE(&s->mch), "multifunction", false);

    object_property_add(obj, PCI_HOST_PROP_PCI_HOLE_START, "int",
                        q35_host_get_pci_hole_start,
                        NULL, NULL, NULL, NULL);

    object_property_add(obj, PCI_HOST_PROP_PCI_HOLE_END, "int",
                        q35_host_get_pci_hole_end,
                        NULL, NULL, NULL, NULL);

    object_property_add(obj, PCI_HOST_PROP_PCI_HOLE64_START, "int",
                        q35_host_get_pci_hole64_start,
                        NULL, NULL, NULL, NULL);

    object_property_add(obj, PCI_HOST_PROP_PCI_HOLE64_END, "int",
                        q35_host_get_pci_hole64_end,
                        NULL, NULL, NULL, NULL);

    object_property_add(obj, PCIE_HOST_MCFG_SIZE, "int",
                        q35_host_get_mmcfg_size,
                        NULL, NULL, NULL, NULL);

    object_property_add_link(obj, MCH_HOST_PROP_RAM_MEM, TYPE_MEMORY_REGION,
                             (Object **) &s->mch.ram_memory,
                             qdev_prop_allow_set_link_before_realize, 0, NULL);

    object_property_add_link(obj, MCH_HOST_PROP_PCI_MEM, TYPE_MEMORY_REGION,
                             (Object **) &s->mch.pci_address_space,
                             qdev_prop_allow_set_link_before_realize, 0, NULL);

    object_property_add_link(obj, MCH_HOST_PROP_SYSTEM_MEM, TYPE_MEMORY_REGION,
                             (Object **) &s->mch.system_memory,
                             qdev_prop_allow_set_link_before_realize, 0, NULL);

    object_property_add_link(obj, MCH_HOST_PROP_IO_MEM, TYPE_MEMORY_REGION,
                             (Object **) &s->mch.address_space_io,
                             qdev_prop_allow_set_link_before_realize, 0, NULL);

    /* Leave enough space for the biggest MCFG BAR */
    /* TODO: this matches current bios behaviour, but
     * it's not a power of two, which means an MTRR
     * can't cover it exactly.
     */
    range_set_bounds(&s->mch.pci_hole,
            MCH_HOST_BRIDGE_PCIEXBAR_DEFAULT + MCH_HOST_BRIDGE_PCIEXBAR_MAX,
            IO_APIC_DEFAULT_ADDRESS - 1);
}

static const TypeInfo q35_host_info = {
    .name       = TYPE_Q35_HOST_DEVICE,
    .parent     = TYPE_PCIE_HOST_BRIDGE,
    .instance_size = sizeof(Q35PCIHost),
    .instance_init = q35_host_initfn,
    .class_init = q35_host_class_init,
};

/****************************************************************************
 * MCH D0:F0
 */

static uint64_t tseg_blackhole_read(void *ptr, hwaddr reg, unsigned size)
{
    return 0xffffffff;
}

static void tseg_blackhole_write(void *opaque, hwaddr addr, uint64_t val,
                                 unsigned width)
{
    /* nothing */
}

static const MemoryRegionOps tseg_blackhole_ops = {
    .read = tseg_blackhole_read,
    .write = tseg_blackhole_write,
    .endianness = DEVICE_NATIVE_ENDIAN,
    .valid.min_access_size = 1,
    .valid.max_access_size = 4,
    .impl.min_access_size = 4,
    .impl.max_access_size = 4,
    .endianness = DEVICE_LITTLE_ENDIAN,
};

/* PCIe MMCFG */
static void mch_update_pciexbar(MCHPCIState *mch)
{
    PCIDevice *pci_dev = PCI_DEVICE(mch);
    BusState *bus = qdev_get_parent_bus(DEVICE(mch));
    PCIExpressHost *pehb = PCIE_HOST_BRIDGE(bus->parent);

    uint64_t pciexbar;
    int enable;
    uint64_t addr;
    uint64_t addr_mask;
    uint32_t length;

    pciexbar = pci_get_quad(pci_dev->config + MCH_HOST_BRIDGE_PCIEXBAR);
    enable = pciexbar & MCH_HOST_BRIDGE_PCIEXBAREN;
    addr_mask = MCH_HOST_BRIDGE_PCIEXBAR_ADMSK;
    switch (pciexbar & MCH_HOST_BRIDGE_PCIEXBAR_LENGTH_MASK) {
    case MCH_HOST_BRIDGE_PCIEXBAR_LENGTH_256M:
        length = 256 * 1024 * 1024;
        break;
    case MCH_HOST_BRIDGE_PCIEXBAR_LENGTH_128M:
        length = 128 * 1024 * 1024;
        addr_mask |= MCH_HOST_BRIDGE_PCIEXBAR_128ADMSK |
            MCH_HOST_BRIDGE_PCIEXBAR_64ADMSK;
        break;
    case MCH_HOST_BRIDGE_PCIEXBAR_LENGTH_64M:
        length = 64 * 1024 * 1024;
        addr_mask |= MCH_HOST_BRIDGE_PCIEXBAR_64ADMSK;
        break;
    case MCH_HOST_BRIDGE_PCIEXBAR_LENGTH_RVD:
    default:
        abort();
    }
    addr = pciexbar & addr_mask;
    pcie_host_mmcfg_update(pehb, enable, addr, length);
    /* Leave enough space for the MCFG BAR */
    /*
     * TODO: this matches current bios behaviour, but it's not a power of two,
     * which means an MTRR can't cover it exactly.
     */
    if (enable) {
        range_set_bounds(&mch->pci_hole,
                         addr + length,
                         IO_APIC_DEFAULT_ADDRESS - 1);
    } else {
        range_set_bounds(&mch->pci_hole,
                         MCH_HOST_BRIDGE_PCIEXBAR_DEFAULT,
                         IO_APIC_DEFAULT_ADDRESS - 1);
    }
}

/* PAM */
static void mch_update_pam(MCHPCIState *mch)
{
    PCIDevice *pd = PCI_DEVICE(mch);
    int i;

    memory_region_transaction_begin();
    for (i = 0; i < 13; i++) {
        pam_update(&mch->pam_regions[i], i,
                   pd->config[MCH_HOST_BRIDGE_PAM0 + ((i + 1) / 2)]);
    }
    memory_region_transaction_commit();
}

/* SMRAM */
static void mch_update_smram(MCHPCIState *mch)
{
    PCIDevice *pd = PCI_DEVICE(mch);
    bool h_smrame = (pd->config[MCH_HOST_BRIDGE_ESMRAMC] & MCH_HOST_BRIDGE_ESMRAMC_H_SMRAME);
    uint32_t tseg_size;

    /* implement SMRAM.D_LCK */
    if (pd->config[MCH_HOST_BRIDGE_SMRAM] & MCH_HOST_BRIDGE_SMRAM_D_LCK) {
        pd->config[MCH_HOST_BRIDGE_SMRAM] &= ~MCH_HOST_BRIDGE_SMRAM_D_OPEN;
        pd->wmask[MCH_HOST_BRIDGE_SMRAM] = MCH_HOST_BRIDGE_SMRAM_WMASK_LCK;
        pd->wmask[MCH_HOST_BRIDGE_ESMRAMC] = MCH_HOST_BRIDGE_ESMRAMC_WMASK_LCK;
    }

    memory_region_transaction_begin();

    if (pd->config[MCH_HOST_BRIDGE_SMRAM] & SMRAM_D_OPEN) {
        /* Hide (!) low SMRAM if H_SMRAME = 1 */
        memory_region_set_enabled(&mch->smram_region, h_smrame);
        /* Show high SMRAM if H_SMRAME = 1 */
        memory_region_set_enabled(&mch->open_high_smram, h_smrame);
    } else {
        /* Hide high SMRAM and low SMRAM */
        memory_region_set_enabled(&mch->smram_region, true);
        memory_region_set_enabled(&mch->open_high_smram, false);
    }

    if (pd->config[MCH_HOST_BRIDGE_SMRAM] & SMRAM_G_SMRAME) {
        memory_region_set_enabled(&mch->low_smram, !h_smrame);
        memory_region_set_enabled(&mch->high_smram, h_smrame);
    } else {
        memory_region_set_enabled(&mch->low_smram, false);
        memory_region_set_enabled(&mch->high_smram, false);
    }

    if (pd->config[MCH_HOST_BRIDGE_ESMRAMC] & MCH_HOST_BRIDGE_ESMRAMC_T_EN) {
        switch (pd->config[MCH_HOST_BRIDGE_ESMRAMC] &
                MCH_HOST_BRIDGE_ESMRAMC_TSEG_SZ_MASK) {
        case MCH_HOST_BRIDGE_ESMRAMC_TSEG_SZ_1MB:
            tseg_size = 1024 * 1024;
            break;
        case MCH_HOST_BRIDGE_ESMRAMC_TSEG_SZ_2MB:
            tseg_size = 1024 * 1024 * 2;
            break;
        case MCH_HOST_BRIDGE_ESMRAMC_TSEG_SZ_8MB:
            tseg_size = 1024 * 1024 * 8;
            break;
        default:
            tseg_size = 0;
            break;
        }
    } else {
        tseg_size = 0;
    }
    memory_region_del_subregion(mch->system_memory, &mch->tseg_blackhole);
    memory_region_set_enabled(&mch->tseg_blackhole, tseg_size);
    memory_region_set_size(&mch->tseg_blackhole, tseg_size);
    memory_region_add_subregion_overlap(mch->system_memory,
                                        mch->below_4g_mem_size - tseg_size,
                                        &mch->tseg_blackhole, 1);

    memory_region_set_enabled(&mch->tseg_window, tseg_size);
    memory_region_set_size(&mch->tseg_window, tseg_size);
    memory_region_set_address(&mch->tseg_window,
                              mch->below_4g_mem_size - tseg_size);
    memory_region_set_alias_offset(&mch->tseg_window,
                                   mch->below_4g_mem_size - tseg_size);

    memory_region_transaction_commit();
}

static void mch_write_config(PCIDevice *d,
                              uint32_t address, uint32_t val, int len)
{
    MCHPCIState *mch = MCH_PCI_DEVICE(d);

    pci_default_write_config(d, address, val, len);

    if (ranges_overlap(address, len, MCH_HOST_BRIDGE_PAM0,
                       MCH_HOST_BRIDGE_PAM_SIZE)) {
        mch_update_pam(mch);
    }

    if (ranges_overlap(address, len, MCH_HOST_BRIDGE_PCIEXBAR,
                       MCH_HOST_BRIDGE_PCIEXBAR_SIZE)) {
        mch_update_pciexbar(mch);
    }

    if (ranges_overlap(address, len, MCH_HOST_BRIDGE_SMRAM,
                       MCH_HOST_BRIDGE_SMRAM_SIZE)) {
        mch_update_smram(mch);
    }
}

static void mch_update(MCHPCIState *mch)
{
    mch_update_pciexbar(mch);
    mch_update_pam(mch);
    mch_update_smram(mch);
}

static int mch_post_load(void *opaque, int version_id)
{
    MCHPCIState *mch = opaque;
    mch_update(mch);
    return 0;
}

static const VMStateDescription vmstate_mch = {
    .name = "mch",
    .version_id = 1,
    .minimum_version_id = 1,
    .post_load = mch_post_load,
    .fields = (VMStateField[]) {
        VMSTATE_PCI_DEVICE(parent_obj, MCHPCIState),
        /* Used to be smm_enabled, which was basically always zero because
         * SeaBIOS hardly uses SMM.  SMRAM is now handled by CPU code.
         */
        VMSTATE_UNUSED(1),
        VMSTATE_END_OF_LIST()
    }
};

static void mch_reset(DeviceState *qdev)
{
    PCIDevice *d = PCI_DEVICE(qdev);
    MCHPCIState *mch = MCH_PCI_DEVICE(d);

    pci_set_quad(d->config + MCH_HOST_BRIDGE_PCIEXBAR,
                 MCH_HOST_BRIDGE_PCIEXBAR_DEFAULT);

    d->config[MCH_HOST_BRIDGE_SMRAM] = MCH_HOST_BRIDGE_SMRAM_DEFAULT;
    d->config[MCH_HOST_BRIDGE_ESMRAMC] = MCH_HOST_BRIDGE_ESMRAMC_DEFAULT;
    d->wmask[MCH_HOST_BRIDGE_SMRAM] = MCH_HOST_BRIDGE_SMRAM_WMASK;
    d->wmask[MCH_HOST_BRIDGE_ESMRAMC] = MCH_HOST_BRIDGE_ESMRAMC_WMASK;

    mch_update(mch);
}

static void mch_realize(PCIDevice *d, Error **errp)
{
    int i;
    MCHPCIState *mch = MCH_PCI_DEVICE(d);

    /* setup pci memory mapping */
    pc_pci_as_mapping_init(OBJECT(mch), mch->system_memory,
                           mch->pci_address_space);

    /* if *disabled* show SMRAM to all CPUs */
    memory_region_init_alias(&mch->smram_region, OBJECT(mch), "smram-region",
                             mch->pci_address_space, 0xa0000, 0x20000);
    memory_region_add_subregion_overlap(mch->system_memory, 0xa0000,
                                        &mch->smram_region, 1);
    memory_region_set_enabled(&mch->smram_region, true);

    memory_region_init_alias(&mch->open_high_smram, OBJECT(mch), "smram-open-high",
                             mch->ram_memory, 0xa0000, 0x20000);
    memory_region_add_subregion_overlap(mch->system_memory, 0xfeda0000,
                                        &mch->open_high_smram, 1);
    memory_region_set_enabled(&mch->open_high_smram, false);

    /* smram, as seen by SMM CPUs */
    memory_region_init(&mch->smram, OBJECT(mch), "smram", 1ull << 32);
    memory_region_set_enabled(&mch->smram, true);
    memory_region_init_alias(&mch->low_smram, OBJECT(mch), "smram-low",
                             mch->ram_memory, 0xa0000, 0x20000);
    memory_region_set_enabled(&mch->low_smram, true);
    memory_region_add_subregion(&mch->smram, 0xa0000, &mch->low_smram);
    memory_region_init_alias(&mch->high_smram, OBJECT(mch), "smram-high",
                             mch->ram_memory, 0xa0000, 0x20000);
    memory_region_set_enabled(&mch->high_smram, true);
    memory_region_add_subregion(&mch->smram, 0xfeda0000, &mch->high_smram);

    memory_region_init_io(&mch->tseg_blackhole, OBJECT(mch),
                          &tseg_blackhole_ops, NULL,
                          "tseg-blackhole", 0);
    memory_region_set_enabled(&mch->tseg_blackhole, false);
    memory_region_add_subregion_overlap(mch->system_memory,
                                        mch->below_4g_mem_size,
                                        &mch->tseg_blackhole, 1);

    memory_region_init_alias(&mch->tseg_window, OBJECT(mch), "tseg-window",
                             mch->ram_memory, mch->below_4g_mem_size, 0);
    memory_region_set_enabled(&mch->tseg_window, false);
    memory_region_add_subregion(&mch->smram, mch->below_4g_mem_size,
                                &mch->tseg_window);
    object_property_add_const_link(qdev_get_machine(), "smram",
                                   OBJECT(&mch->smram), &error_abort);

    init_pam(DEVICE(mch), mch->ram_memory, mch->system_memory,
             mch->pci_address_space, &mch->pam_regions[0],
             PAM_BIOS_BASE, PAM_BIOS_SIZE);
    for (i = 0; i < 12; ++i) {
        init_pam(DEVICE(mch), mch->ram_memory, mch->system_memory,
                 mch->pci_address_space, &mch->pam_regions[i+1],
                 PAM_EXPAN_BASE + i * PAM_EXPAN_SIZE, PAM_EXPAN_SIZE);
    }
}

uint64_t mch_mcfg_base(void)
{
    bool ambiguous;
    Object *o = object_resolve_path_type("", TYPE_MCH_PCI_DEVICE, &ambiguous);
    if (!o) {
        return 0;
    }
    return MCH_HOST_BRIDGE_PCIEXBAR_DEFAULT;
}

static void mch_class_init(ObjectClass *klass, void *data)
{
    PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
    DeviceClass *dc = DEVICE_CLASS(klass);

    k->realize = mch_realize;
    k->config_write = mch_write_config;
    dc->reset = mch_reset;
    set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
    dc->desc = "Host bridge";
    dc->vmsd = &vmstate_mch;
    k->vendor_id = PCI_VENDOR_ID_INTEL;
    k->device_id = PCI_DEVICE_ID_INTEL_Q35_MCH;
    k->revision = MCH_HOST_BRIDGE_REVISION_DEFAULT;
    k->class_id = PCI_CLASS_BRIDGE_HOST;
    /*
     * PCI-facing part of the host bridge, not usable without the
     * host-facing part, which can't be device_add'ed, yet.
     */
    dc->cannot_instantiate_with_device_add_yet = true;
}

static const TypeInfo mch_info = {
    .name = TYPE_MCH_PCI_DEVICE,
    .parent = TYPE_PCI_DEVICE,
    .instance_size = sizeof(MCHPCIState),
    .class_init = mch_class_init,
};

static void q35_register(void)
{
    type_register_static(&mch_info);
    type_register_static(&q35_host_info);
}

type_init(q35_register);