xref: /openbmc/qemu/hw/pci-host/q35.c (revision 0b1183e3)
1 /*
2  * QEMU MCH/ICH9 PCI Bridge Emulation
3  *
4  * Copyright (c) 2006 Fabrice Bellard
5  * Copyright (c) 2009, 2010, 2011
6  *               Isaku Yamahata <yamahata at valinux co jp>
7  *               VA Linux Systems Japan K.K.
8  * Copyright (C) 2012 Jason Baron <jbaron@redhat.com>
9  *
10  * This is based on piix.c, but heavily modified.
11  *
12  * Permission is hereby granted, free of charge, to any person obtaining a copy
13  * of this software and associated documentation files (the "Software"), to deal
14  * in the Software without restriction, including without limitation the rights
15  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
16  * copies of the Software, and to permit persons to whom the Software is
17  * furnished to do so, subject to the following conditions:
18  *
19  * The above copyright notice and this permission notice shall be included in
20  * all copies or substantial portions of the Software.
21  *
22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
23  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
24  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
25  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
26  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
27  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
28  * THE SOFTWARE.
29  */
30 #include "qemu/osdep.h"
31 #include "hw/hw.h"
32 #include "hw/pci-host/q35.h"
33 #include "qapi/error.h"
34 #include "qapi/visitor.h"
35 
36 /****************************************************************************
37  * Q35 host
38  */
39 
40 static void q35_host_realize(DeviceState *dev, Error **errp)
41 {
42     PCIHostState *pci = PCI_HOST_BRIDGE(dev);
43     Q35PCIHost *s = Q35_HOST_DEVICE(dev);
44     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
45 
46     sysbus_add_io(sbd, MCH_HOST_BRIDGE_CONFIG_ADDR, &pci->conf_mem);
47     sysbus_init_ioports(sbd, MCH_HOST_BRIDGE_CONFIG_ADDR, 4);
48 
49     sysbus_add_io(sbd, MCH_HOST_BRIDGE_CONFIG_DATA, &pci->data_mem);
50     sysbus_init_ioports(sbd, MCH_HOST_BRIDGE_CONFIG_DATA, 4);
51 
52     pci->bus = pci_bus_new(DEVICE(s), "pcie.0",
53                            s->mch.pci_address_space, s->mch.address_space_io,
54                            0, TYPE_PCIE_BUS);
55     PC_MACHINE(qdev_get_machine())->bus = pci->bus;
56     qdev_set_parent_bus(DEVICE(&s->mch), BUS(pci->bus));
57     qdev_init_nofail(DEVICE(&s->mch));
58 }
59 
60 static const char *q35_host_root_bus_path(PCIHostState *host_bridge,
61                                           PCIBus *rootbus)
62 {
63     Q35PCIHost *s = Q35_HOST_DEVICE(host_bridge);
64 
65      /* For backwards compat with old device paths */
66     if (s->mch.short_root_bus) {
67         return "0000";
68     }
69     return "0000:00";
70 }
71 
72 static void q35_host_get_pci_hole_start(Object *obj, Visitor *v,
73                                         const char *name, void *opaque,
74                                         Error **errp)
75 {
76     Q35PCIHost *s = Q35_HOST_DEVICE(obj);
77     uint64_t val64;
78     uint32_t value;
79 
80     val64 = range_is_empty(&s->mch.pci_hole)
81         ? 0 : range_lob(&s->mch.pci_hole);
82     value = val64;
83     assert(value == val64);
84     visit_type_uint32(v, name, &value, errp);
85 }
86 
87 static void q35_host_get_pci_hole_end(Object *obj, Visitor *v,
88                                       const char *name, void *opaque,
89                                       Error **errp)
90 {
91     Q35PCIHost *s = Q35_HOST_DEVICE(obj);
92     uint64_t val64;
93     uint32_t value;
94 
95     val64 = range_is_empty(&s->mch.pci_hole)
96         ? 0 : range_upb(&s->mch.pci_hole) + 1;
97     value = val64;
98     assert(value == val64);
99     visit_type_uint32(v, name, &value, errp);
100 }
101 
102 static void q35_host_get_pci_hole64_start(Object *obj, Visitor *v,
103                                           const char *name, void *opaque,
104                                           Error **errp)
105 {
106     PCIHostState *h = PCI_HOST_BRIDGE(obj);
107     Range w64;
108     uint64_t value;
109 
110     pci_bus_get_w64_range(h->bus, &w64);
111     value = range_is_empty(&w64) ? 0 : range_lob(&w64);
112     visit_type_uint64(v, name, &value, errp);
113 }
114 
115 static void q35_host_get_pci_hole64_end(Object *obj, Visitor *v,
116                                         const char *name, void *opaque,
117                                         Error **errp)
118 {
119     PCIHostState *h = PCI_HOST_BRIDGE(obj);
120     Range w64;
121     uint64_t value;
122 
123     pci_bus_get_w64_range(h->bus, &w64);
124     value = range_is_empty(&w64) ? 0 : range_upb(&w64) + 1;
125     visit_type_uint64(v, name, &value, errp);
126 }
127 
128 static void q35_host_get_mmcfg_size(Object *obj, Visitor *v, const char *name,
129                                     void *opaque, Error **errp)
130 {
131     PCIExpressHost *e = PCIE_HOST_BRIDGE(obj);
132 
133     visit_type_uint64(v, name, &e->size, errp);
134 }
135 
136 static Property q35_host_props[] = {
137     DEFINE_PROP_UINT64(PCIE_HOST_MCFG_BASE, Q35PCIHost, parent_obj.base_addr,
138                         MCH_HOST_BRIDGE_PCIEXBAR_DEFAULT),
139     DEFINE_PROP_SIZE(PCI_HOST_PROP_PCI_HOLE64_SIZE, Q35PCIHost,
140                      mch.pci_hole64_size, DEFAULT_PCI_HOLE64_SIZE),
141     DEFINE_PROP_UINT32("short_root_bus", Q35PCIHost, mch.short_root_bus, 0),
142     DEFINE_PROP_SIZE(PCI_HOST_BELOW_4G_MEM_SIZE, Q35PCIHost,
143                      mch.below_4g_mem_size, 0),
144     DEFINE_PROP_SIZE(PCI_HOST_ABOVE_4G_MEM_SIZE, Q35PCIHost,
145                      mch.above_4g_mem_size, 0),
146     DEFINE_PROP_END_OF_LIST(),
147 };
148 
149 static void q35_host_class_init(ObjectClass *klass, void *data)
150 {
151     DeviceClass *dc = DEVICE_CLASS(klass);
152     PCIHostBridgeClass *hc = PCI_HOST_BRIDGE_CLASS(klass);
153 
154     hc->root_bus_path = q35_host_root_bus_path;
155     dc->realize = q35_host_realize;
156     dc->props = q35_host_props;
157     /* Reason: needs to be wired up by pc_q35_init */
158     dc->user_creatable = false;
159     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
160     dc->fw_name = "pci";
161 }
162 
163 static void q35_host_initfn(Object *obj)
164 {
165     Q35PCIHost *s = Q35_HOST_DEVICE(obj);
166     PCIHostState *phb = PCI_HOST_BRIDGE(obj);
167 
168     memory_region_init_io(&phb->conf_mem, obj, &pci_host_conf_le_ops, phb,
169                           "pci-conf-idx", 4);
170     memory_region_init_io(&phb->data_mem, obj, &pci_host_data_le_ops, phb,
171                           "pci-conf-data", 4);
172 
173     object_initialize(&s->mch, sizeof(s->mch), TYPE_MCH_PCI_DEVICE);
174     object_property_add_child(OBJECT(s), "mch", OBJECT(&s->mch), NULL);
175     qdev_prop_set_int32(DEVICE(&s->mch), "addr", PCI_DEVFN(0, 0));
176     qdev_prop_set_bit(DEVICE(&s->mch), "multifunction", false);
177 
178     object_property_add(obj, PCI_HOST_PROP_PCI_HOLE_START, "uint32",
179                         q35_host_get_pci_hole_start,
180                         NULL, NULL, NULL, NULL);
181 
182     object_property_add(obj, PCI_HOST_PROP_PCI_HOLE_END, "uint32",
183                         q35_host_get_pci_hole_end,
184                         NULL, NULL, NULL, NULL);
185 
186     object_property_add(obj, PCI_HOST_PROP_PCI_HOLE64_START, "uint64",
187                         q35_host_get_pci_hole64_start,
188                         NULL, NULL, NULL, NULL);
189 
190     object_property_add(obj, PCI_HOST_PROP_PCI_HOLE64_END, "uint64",
191                         q35_host_get_pci_hole64_end,
192                         NULL, NULL, NULL, NULL);
193 
194     object_property_add(obj, PCIE_HOST_MCFG_SIZE, "uint64",
195                         q35_host_get_mmcfg_size,
196                         NULL, NULL, NULL, NULL);
197 
198     object_property_add_link(obj, MCH_HOST_PROP_RAM_MEM, TYPE_MEMORY_REGION,
199                              (Object **) &s->mch.ram_memory,
200                              qdev_prop_allow_set_link_before_realize, 0, NULL);
201 
202     object_property_add_link(obj, MCH_HOST_PROP_PCI_MEM, TYPE_MEMORY_REGION,
203                              (Object **) &s->mch.pci_address_space,
204                              qdev_prop_allow_set_link_before_realize, 0, NULL);
205 
206     object_property_add_link(obj, MCH_HOST_PROP_SYSTEM_MEM, TYPE_MEMORY_REGION,
207                              (Object **) &s->mch.system_memory,
208                              qdev_prop_allow_set_link_before_realize, 0, NULL);
209 
210     object_property_add_link(obj, MCH_HOST_PROP_IO_MEM, TYPE_MEMORY_REGION,
211                              (Object **) &s->mch.address_space_io,
212                              qdev_prop_allow_set_link_before_realize, 0, NULL);
213 
214     /* Leave enough space for the biggest MCFG BAR */
215     /* TODO: this matches current bios behaviour, but
216      * it's not a power of two, which means an MTRR
217      * can't cover it exactly.
218      */
219     range_set_bounds(&s->mch.pci_hole,
220             MCH_HOST_BRIDGE_PCIEXBAR_DEFAULT + MCH_HOST_BRIDGE_PCIEXBAR_MAX,
221             IO_APIC_DEFAULT_ADDRESS - 1);
222 }
223 
224 static const TypeInfo q35_host_info = {
225     .name       = TYPE_Q35_HOST_DEVICE,
226     .parent     = TYPE_PCIE_HOST_BRIDGE,
227     .instance_size = sizeof(Q35PCIHost),
228     .instance_init = q35_host_initfn,
229     .class_init = q35_host_class_init,
230 };
231 
232 /****************************************************************************
233  * MCH D0:F0
234  */
235 
236 static uint64_t tseg_blackhole_read(void *ptr, hwaddr reg, unsigned size)
237 {
238     return 0xffffffff;
239 }
240 
241 static void tseg_blackhole_write(void *opaque, hwaddr addr, uint64_t val,
242                                  unsigned width)
243 {
244     /* nothing */
245 }
246 
247 static const MemoryRegionOps tseg_blackhole_ops = {
248     .read = tseg_blackhole_read,
249     .write = tseg_blackhole_write,
250     .endianness = DEVICE_NATIVE_ENDIAN,
251     .valid.min_access_size = 1,
252     .valid.max_access_size = 4,
253     .impl.min_access_size = 4,
254     .impl.max_access_size = 4,
255     .endianness = DEVICE_LITTLE_ENDIAN,
256 };
257 
258 /* PCIe MMCFG */
259 static void mch_update_pciexbar(MCHPCIState *mch)
260 {
261     PCIDevice *pci_dev = PCI_DEVICE(mch);
262     BusState *bus = qdev_get_parent_bus(DEVICE(mch));
263     PCIExpressHost *pehb = PCIE_HOST_BRIDGE(bus->parent);
264 
265     uint64_t pciexbar;
266     int enable;
267     uint64_t addr;
268     uint64_t addr_mask;
269     uint32_t length;
270 
271     pciexbar = pci_get_quad(pci_dev->config + MCH_HOST_BRIDGE_PCIEXBAR);
272     enable = pciexbar & MCH_HOST_BRIDGE_PCIEXBAREN;
273     addr_mask = MCH_HOST_BRIDGE_PCIEXBAR_ADMSK;
274     switch (pciexbar & MCH_HOST_BRIDGE_PCIEXBAR_LENGTH_MASK) {
275     case MCH_HOST_BRIDGE_PCIEXBAR_LENGTH_256M:
276         length = 256 * 1024 * 1024;
277         break;
278     case MCH_HOST_BRIDGE_PCIEXBAR_LENGTH_128M:
279         length = 128 * 1024 * 1024;
280         addr_mask |= MCH_HOST_BRIDGE_PCIEXBAR_128ADMSK |
281             MCH_HOST_BRIDGE_PCIEXBAR_64ADMSK;
282         break;
283     case MCH_HOST_BRIDGE_PCIEXBAR_LENGTH_64M:
284         length = 64 * 1024 * 1024;
285         addr_mask |= MCH_HOST_BRIDGE_PCIEXBAR_64ADMSK;
286         break;
287     case MCH_HOST_BRIDGE_PCIEXBAR_LENGTH_RVD:
288     default:
289         abort();
290     }
291     addr = pciexbar & addr_mask;
292     pcie_host_mmcfg_update(pehb, enable, addr, length);
293     /* Leave enough space for the MCFG BAR */
294     /*
295      * TODO: this matches current bios behaviour, but it's not a power of two,
296      * which means an MTRR can't cover it exactly.
297      */
298     if (enable) {
299         range_set_bounds(&mch->pci_hole,
300                          addr + length,
301                          IO_APIC_DEFAULT_ADDRESS - 1);
302     } else {
303         range_set_bounds(&mch->pci_hole,
304                          MCH_HOST_BRIDGE_PCIEXBAR_DEFAULT,
305                          IO_APIC_DEFAULT_ADDRESS - 1);
306     }
307 }
308 
309 /* PAM */
310 static void mch_update_pam(MCHPCIState *mch)
311 {
312     PCIDevice *pd = PCI_DEVICE(mch);
313     int i;
314 
315     memory_region_transaction_begin();
316     for (i = 0; i < 13; i++) {
317         pam_update(&mch->pam_regions[i], i,
318                    pd->config[MCH_HOST_BRIDGE_PAM0 + ((i + 1) / 2)]);
319     }
320     memory_region_transaction_commit();
321 }
322 
323 /* SMRAM */
324 static void mch_update_smram(MCHPCIState *mch)
325 {
326     PCIDevice *pd = PCI_DEVICE(mch);
327     bool h_smrame = (pd->config[MCH_HOST_BRIDGE_ESMRAMC] & MCH_HOST_BRIDGE_ESMRAMC_H_SMRAME);
328     uint32_t tseg_size;
329 
330     /* implement SMRAM.D_LCK */
331     if (pd->config[MCH_HOST_BRIDGE_SMRAM] & MCH_HOST_BRIDGE_SMRAM_D_LCK) {
332         pd->config[MCH_HOST_BRIDGE_SMRAM] &= ~MCH_HOST_BRIDGE_SMRAM_D_OPEN;
333         pd->wmask[MCH_HOST_BRIDGE_SMRAM] = MCH_HOST_BRIDGE_SMRAM_WMASK_LCK;
334         pd->wmask[MCH_HOST_BRIDGE_ESMRAMC] = MCH_HOST_BRIDGE_ESMRAMC_WMASK_LCK;
335     }
336 
337     memory_region_transaction_begin();
338 
339     if (pd->config[MCH_HOST_BRIDGE_SMRAM] & SMRAM_D_OPEN) {
340         /* Hide (!) low SMRAM if H_SMRAME = 1 */
341         memory_region_set_enabled(&mch->smram_region, h_smrame);
342         /* Show high SMRAM if H_SMRAME = 1 */
343         memory_region_set_enabled(&mch->open_high_smram, h_smrame);
344     } else {
345         /* Hide high SMRAM and low SMRAM */
346         memory_region_set_enabled(&mch->smram_region, true);
347         memory_region_set_enabled(&mch->open_high_smram, false);
348     }
349 
350     if (pd->config[MCH_HOST_BRIDGE_SMRAM] & SMRAM_G_SMRAME) {
351         memory_region_set_enabled(&mch->low_smram, !h_smrame);
352         memory_region_set_enabled(&mch->high_smram, h_smrame);
353     } else {
354         memory_region_set_enabled(&mch->low_smram, false);
355         memory_region_set_enabled(&mch->high_smram, false);
356     }
357 
358     if (pd->config[MCH_HOST_BRIDGE_ESMRAMC] & MCH_HOST_BRIDGE_ESMRAMC_T_EN) {
359         switch (pd->config[MCH_HOST_BRIDGE_ESMRAMC] &
360                 MCH_HOST_BRIDGE_ESMRAMC_TSEG_SZ_MASK) {
361         case MCH_HOST_BRIDGE_ESMRAMC_TSEG_SZ_1MB:
362             tseg_size = 1024 * 1024;
363             break;
364         case MCH_HOST_BRIDGE_ESMRAMC_TSEG_SZ_2MB:
365             tseg_size = 1024 * 1024 * 2;
366             break;
367         case MCH_HOST_BRIDGE_ESMRAMC_TSEG_SZ_8MB:
368             tseg_size = 1024 * 1024 * 8;
369             break;
370         default:
371             tseg_size = 1024 * 1024 * (uint32_t)mch->ext_tseg_mbytes;
372             break;
373         }
374     } else {
375         tseg_size = 0;
376     }
377     memory_region_del_subregion(mch->system_memory, &mch->tseg_blackhole);
378     memory_region_set_enabled(&mch->tseg_blackhole, tseg_size);
379     memory_region_set_size(&mch->tseg_blackhole, tseg_size);
380     memory_region_add_subregion_overlap(mch->system_memory,
381                                         mch->below_4g_mem_size - tseg_size,
382                                         &mch->tseg_blackhole, 1);
383 
384     memory_region_set_enabled(&mch->tseg_window, tseg_size);
385     memory_region_set_size(&mch->tseg_window, tseg_size);
386     memory_region_set_address(&mch->tseg_window,
387                               mch->below_4g_mem_size - tseg_size);
388     memory_region_set_alias_offset(&mch->tseg_window,
389                                    mch->below_4g_mem_size - tseg_size);
390 
391     memory_region_transaction_commit();
392 }
393 
394 static void mch_update_ext_tseg_mbytes(MCHPCIState *mch)
395 {
396     PCIDevice *pd = PCI_DEVICE(mch);
397     uint8_t *reg = pd->config + MCH_HOST_BRIDGE_EXT_TSEG_MBYTES;
398 
399     if (mch->ext_tseg_mbytes > 0 &&
400         pci_get_word(reg) == MCH_HOST_BRIDGE_EXT_TSEG_MBYTES_QUERY) {
401         pci_set_word(reg, mch->ext_tseg_mbytes);
402     }
403 }
404 
405 static void mch_write_config(PCIDevice *d,
406                               uint32_t address, uint32_t val, int len)
407 {
408     MCHPCIState *mch = MCH_PCI_DEVICE(d);
409 
410     pci_default_write_config(d, address, val, len);
411 
412     if (ranges_overlap(address, len, MCH_HOST_BRIDGE_PAM0,
413                        MCH_HOST_BRIDGE_PAM_SIZE)) {
414         mch_update_pam(mch);
415     }
416 
417     if (ranges_overlap(address, len, MCH_HOST_BRIDGE_PCIEXBAR,
418                        MCH_HOST_BRIDGE_PCIEXBAR_SIZE)) {
419         mch_update_pciexbar(mch);
420     }
421 
422     if (ranges_overlap(address, len, MCH_HOST_BRIDGE_SMRAM,
423                        MCH_HOST_BRIDGE_SMRAM_SIZE)) {
424         mch_update_smram(mch);
425     }
426 
427     if (ranges_overlap(address, len, MCH_HOST_BRIDGE_EXT_TSEG_MBYTES,
428                        MCH_HOST_BRIDGE_EXT_TSEG_MBYTES_SIZE)) {
429         mch_update_ext_tseg_mbytes(mch);
430     }
431 }
432 
433 static void mch_update(MCHPCIState *mch)
434 {
435     mch_update_pciexbar(mch);
436     mch_update_pam(mch);
437     mch_update_smram(mch);
438     mch_update_ext_tseg_mbytes(mch);
439 }
440 
441 static int mch_post_load(void *opaque, int version_id)
442 {
443     MCHPCIState *mch = opaque;
444     mch_update(mch);
445     return 0;
446 }
447 
448 static const VMStateDescription vmstate_mch = {
449     .name = "mch",
450     .version_id = 1,
451     .minimum_version_id = 1,
452     .post_load = mch_post_load,
453     .fields = (VMStateField[]) {
454         VMSTATE_PCI_DEVICE(parent_obj, MCHPCIState),
455         /* Used to be smm_enabled, which was basically always zero because
456          * SeaBIOS hardly uses SMM.  SMRAM is now handled by CPU code.
457          */
458         VMSTATE_UNUSED(1),
459         VMSTATE_END_OF_LIST()
460     }
461 };
462 
463 static void mch_reset(DeviceState *qdev)
464 {
465     PCIDevice *d = PCI_DEVICE(qdev);
466     MCHPCIState *mch = MCH_PCI_DEVICE(d);
467 
468     pci_set_quad(d->config + MCH_HOST_BRIDGE_PCIEXBAR,
469                  MCH_HOST_BRIDGE_PCIEXBAR_DEFAULT);
470 
471     d->config[MCH_HOST_BRIDGE_SMRAM] = MCH_HOST_BRIDGE_SMRAM_DEFAULT;
472     d->config[MCH_HOST_BRIDGE_ESMRAMC] = MCH_HOST_BRIDGE_ESMRAMC_DEFAULT;
473     d->wmask[MCH_HOST_BRIDGE_SMRAM] = MCH_HOST_BRIDGE_SMRAM_WMASK;
474     d->wmask[MCH_HOST_BRIDGE_ESMRAMC] = MCH_HOST_BRIDGE_ESMRAMC_WMASK;
475 
476     if (mch->ext_tseg_mbytes > 0) {
477         pci_set_word(d->config + MCH_HOST_BRIDGE_EXT_TSEG_MBYTES,
478                      MCH_HOST_BRIDGE_EXT_TSEG_MBYTES_QUERY);
479     }
480 
481     mch_update(mch);
482 }
483 
484 static void mch_realize(PCIDevice *d, Error **errp)
485 {
486     int i;
487     MCHPCIState *mch = MCH_PCI_DEVICE(d);
488 
489     if (mch->ext_tseg_mbytes > MCH_HOST_BRIDGE_EXT_TSEG_MBYTES_MAX) {
490         error_setg(errp, "invalid extended-tseg-mbytes value: %" PRIu16,
491                    mch->ext_tseg_mbytes);
492         return;
493     }
494 
495     /* setup pci memory mapping */
496     pc_pci_as_mapping_init(OBJECT(mch), mch->system_memory,
497                            mch->pci_address_space);
498 
499     /* if *disabled* show SMRAM to all CPUs */
500     memory_region_init_alias(&mch->smram_region, OBJECT(mch), "smram-region",
501                              mch->pci_address_space, 0xa0000, 0x20000);
502     memory_region_add_subregion_overlap(mch->system_memory, 0xa0000,
503                                         &mch->smram_region, 1);
504     memory_region_set_enabled(&mch->smram_region, true);
505 
506     memory_region_init_alias(&mch->open_high_smram, OBJECT(mch), "smram-open-high",
507                              mch->ram_memory, 0xa0000, 0x20000);
508     memory_region_add_subregion_overlap(mch->system_memory, 0xfeda0000,
509                                         &mch->open_high_smram, 1);
510     memory_region_set_enabled(&mch->open_high_smram, false);
511 
512     /* smram, as seen by SMM CPUs */
513     memory_region_init(&mch->smram, OBJECT(mch), "smram", 1ull << 32);
514     memory_region_set_enabled(&mch->smram, true);
515     memory_region_init_alias(&mch->low_smram, OBJECT(mch), "smram-low",
516                              mch->ram_memory, 0xa0000, 0x20000);
517     memory_region_set_enabled(&mch->low_smram, true);
518     memory_region_add_subregion(&mch->smram, 0xa0000, &mch->low_smram);
519     memory_region_init_alias(&mch->high_smram, OBJECT(mch), "smram-high",
520                              mch->ram_memory, 0xa0000, 0x20000);
521     memory_region_set_enabled(&mch->high_smram, true);
522     memory_region_add_subregion(&mch->smram, 0xfeda0000, &mch->high_smram);
523 
524     memory_region_init_io(&mch->tseg_blackhole, OBJECT(mch),
525                           &tseg_blackhole_ops, NULL,
526                           "tseg-blackhole", 0);
527     memory_region_set_enabled(&mch->tseg_blackhole, false);
528     memory_region_add_subregion_overlap(mch->system_memory,
529                                         mch->below_4g_mem_size,
530                                         &mch->tseg_blackhole, 1);
531 
532     memory_region_init_alias(&mch->tseg_window, OBJECT(mch), "tseg-window",
533                              mch->ram_memory, mch->below_4g_mem_size, 0);
534     memory_region_set_enabled(&mch->tseg_window, false);
535     memory_region_add_subregion(&mch->smram, mch->below_4g_mem_size,
536                                 &mch->tseg_window);
537     object_property_add_const_link(qdev_get_machine(), "smram",
538                                    OBJECT(&mch->smram), &error_abort);
539 
540     init_pam(DEVICE(mch), mch->ram_memory, mch->system_memory,
541              mch->pci_address_space, &mch->pam_regions[0],
542              PAM_BIOS_BASE, PAM_BIOS_SIZE);
543     for (i = 0; i < 12; ++i) {
544         init_pam(DEVICE(mch), mch->ram_memory, mch->system_memory,
545                  mch->pci_address_space, &mch->pam_regions[i+1],
546                  PAM_EXPAN_BASE + i * PAM_EXPAN_SIZE, PAM_EXPAN_SIZE);
547     }
548 }
549 
550 uint64_t mch_mcfg_base(void)
551 {
552     bool ambiguous;
553     Object *o = object_resolve_path_type("", TYPE_MCH_PCI_DEVICE, &ambiguous);
554     if (!o) {
555         return 0;
556     }
557     return MCH_HOST_BRIDGE_PCIEXBAR_DEFAULT;
558 }
559 
560 static Property mch_props[] = {
561     DEFINE_PROP_UINT16("extended-tseg-mbytes", MCHPCIState, ext_tseg_mbytes,
562                        16),
563     DEFINE_PROP_END_OF_LIST(),
564 };
565 
566 static void mch_class_init(ObjectClass *klass, void *data)
567 {
568     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
569     DeviceClass *dc = DEVICE_CLASS(klass);
570 
571     k->realize = mch_realize;
572     k->config_write = mch_write_config;
573     dc->reset = mch_reset;
574     dc->props = mch_props;
575     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
576     dc->desc = "Host bridge";
577     dc->vmsd = &vmstate_mch;
578     k->vendor_id = PCI_VENDOR_ID_INTEL;
579     k->device_id = PCI_DEVICE_ID_INTEL_Q35_MCH;
580     k->revision = MCH_HOST_BRIDGE_REVISION_DEFAULT;
581     k->class_id = PCI_CLASS_BRIDGE_HOST;
582     /*
583      * PCI-facing part of the host bridge, not usable without the
584      * host-facing part, which can't be device_add'ed, yet.
585      */
586     dc->user_creatable = false;
587 }
588 
589 static const TypeInfo mch_info = {
590     .name = TYPE_MCH_PCI_DEVICE,
591     .parent = TYPE_PCI_DEVICE,
592     .instance_size = sizeof(MCHPCIState),
593     .class_init = mch_class_init,
594 };
595 
596 static void q35_register(void)
597 {
598     type_register_static(&mch_info);
599     type_register_static(&q35_host_info);
600 }
601 
602 type_init(q35_register);
603