xref: /openbmc/qemu/hw/pci-host/i440fx.c (revision f480f6e8)
1 /*
2  * QEMU i440FX/PIIX3 PCI Bridge Emulation
3  *
4  * Copyright (c) 2006 Fabrice Bellard
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 #include "qemu/osdep.h"
26 #include "hw/i386/pc.h"
27 #include "hw/pci/pci.h"
28 #include "hw/pci/pci_host.h"
29 #include "hw/pci-host/i440fx.h"
30 #include "hw/qdev-properties.h"
31 #include "hw/sysbus.h"
32 #include "qapi/error.h"
33 #include "migration/vmstate.h"
34 #include "hw/pci-host/pam.h"
35 #include "qapi/visitor.h"
36 #include "qemu/error-report.h"
37 
38 /*
39  * I440FX chipset data sheet.
40  * https://wiki.qemu.org/File:29054901.pdf
41  */
42 
43 #define I440FX_PCI_HOST_BRIDGE(obj) \
44     OBJECT_CHECK(I440FXState, (obj), TYPE_I440FX_PCI_HOST_BRIDGE)
45 
46 typedef struct I440FXState {
47     PCIHostState parent_obj;
48     Range pci_hole;
49     uint64_t pci_hole64_size;
50     bool pci_hole64_fix;
51     uint32_t short_root_bus;
52 } I440FXState;
53 
54 #define I440FX_PCI_DEVICE(obj) \
55     OBJECT_CHECK(PCII440FXState, (obj), TYPE_I440FX_PCI_DEVICE)
56 
57 struct PCII440FXState {
58     /*< private >*/
59     PCIDevice parent_obj;
60     /*< public >*/
61 
62     MemoryRegion *system_memory;
63     MemoryRegion *pci_address_space;
64     MemoryRegion *ram_memory;
65     PAMMemoryRegion pam_regions[13];
66     MemoryRegion smram_region;
67     MemoryRegion smram, low_smram;
68 };
69 
70 
71 #define I440FX_PAM      0x59
72 #define I440FX_PAM_SIZE 7
73 #define I440FX_SMRAM    0x72
74 
75 /* Keep it 2G to comply with older win32 guests */
76 #define I440FX_PCI_HOST_HOLE64_SIZE_DEFAULT (1ULL << 31)
77 
78 /* Older coreboot versions (4.0 and older) read a config register that doesn't
79  * exist in real hardware, to get the RAM size from QEMU.
80  */
81 #define I440FX_COREBOOT_RAM_SIZE 0x57
82 
83 static void i440fx_update_memory_mappings(PCII440FXState *d)
84 {
85     int i;
86     PCIDevice *pd = PCI_DEVICE(d);
87 
88     memory_region_transaction_begin();
89     for (i = 0; i < ARRAY_SIZE(d->pam_regions); i++) {
90         pam_update(&d->pam_regions[i], i,
91                    pd->config[I440FX_PAM + DIV_ROUND_UP(i, 2)]);
92     }
93     memory_region_set_enabled(&d->smram_region,
94                               !(pd->config[I440FX_SMRAM] & SMRAM_D_OPEN));
95     memory_region_set_enabled(&d->smram,
96                               pd->config[I440FX_SMRAM] & SMRAM_G_SMRAME);
97     memory_region_transaction_commit();
98 }
99 
100 
101 static void i440fx_write_config(PCIDevice *dev,
102                                 uint32_t address, uint32_t val, int len)
103 {
104     PCII440FXState *d = I440FX_PCI_DEVICE(dev);
105 
106     /* XXX: implement SMRAM.D_LOCK */
107     pci_default_write_config(dev, address, val, len);
108     if (ranges_overlap(address, len, I440FX_PAM, I440FX_PAM_SIZE) ||
109         range_covers_byte(address, len, I440FX_SMRAM)) {
110         i440fx_update_memory_mappings(d);
111     }
112 }
113 
114 static int i440fx_post_load(void *opaque, int version_id)
115 {
116     PCII440FXState *d = opaque;
117 
118     i440fx_update_memory_mappings(d);
119     return 0;
120 }
121 
122 static const VMStateDescription vmstate_i440fx = {
123     .name = "I440FX",
124     .version_id = 3,
125     .minimum_version_id = 3,
126     .post_load = i440fx_post_load,
127     .fields = (VMStateField[]) {
128         VMSTATE_PCI_DEVICE(parent_obj, PCII440FXState),
129         /* Used to be smm_enabled, which was basically always zero because
130          * SeaBIOS hardly uses SMM.  SMRAM is now handled by CPU code.
131          */
132         VMSTATE_UNUSED(1),
133         VMSTATE_END_OF_LIST()
134     }
135 };
136 
137 static void i440fx_pcihost_get_pci_hole_start(Object *obj, Visitor *v,
138                                               const char *name, void *opaque,
139                                               Error **errp)
140 {
141     I440FXState *s = I440FX_PCI_HOST_BRIDGE(obj);
142     uint64_t val64;
143     uint32_t value;
144 
145     val64 = range_is_empty(&s->pci_hole) ? 0 : range_lob(&s->pci_hole);
146     value = val64;
147     assert(value == val64);
148     visit_type_uint32(v, name, &value, errp);
149 }
150 
151 static void i440fx_pcihost_get_pci_hole_end(Object *obj, Visitor *v,
152                                             const char *name, void *opaque,
153                                             Error **errp)
154 {
155     I440FXState *s = I440FX_PCI_HOST_BRIDGE(obj);
156     uint64_t val64;
157     uint32_t value;
158 
159     val64 = range_is_empty(&s->pci_hole) ? 0 : range_upb(&s->pci_hole) + 1;
160     value = val64;
161     assert(value == val64);
162     visit_type_uint32(v, name, &value, errp);
163 }
164 
165 /*
166  * The 64bit PCI hole start is set by the Guest firmware
167  * as the address of the first 64bit PCI MEM resource.
168  * If no PCI device has resources on the 64bit area,
169  * the 64bit PCI hole will start after "over 4G RAM" and the
170  * reserved space for memory hotplug if any.
171  */
172 static uint64_t i440fx_pcihost_get_pci_hole64_start_value(Object *obj)
173 {
174     PCIHostState *h = PCI_HOST_BRIDGE(obj);
175     I440FXState *s = I440FX_PCI_HOST_BRIDGE(obj);
176     Range w64;
177     uint64_t value;
178 
179     pci_bus_get_w64_range(h->bus, &w64);
180     value = range_is_empty(&w64) ? 0 : range_lob(&w64);
181     if (!value && s->pci_hole64_fix) {
182         value = pc_pci_hole64_start();
183     }
184     return value;
185 }
186 
187 static void i440fx_pcihost_get_pci_hole64_start(Object *obj, Visitor *v,
188                                                 const char *name,
189                                                 void *opaque, Error **errp)
190 {
191     uint64_t hole64_start = i440fx_pcihost_get_pci_hole64_start_value(obj);
192 
193     visit_type_uint64(v, name, &hole64_start, errp);
194 }
195 
196 /*
197  * The 64bit PCI hole end is set by the Guest firmware
198  * as the address of the last 64bit PCI MEM resource.
199  * Then it is expanded to the PCI_HOST_PROP_PCI_HOLE64_SIZE
200  * that can be configured by the user.
201  */
202 static void i440fx_pcihost_get_pci_hole64_end(Object *obj, Visitor *v,
203                                               const char *name, void *opaque,
204                                               Error **errp)
205 {
206     PCIHostState *h = PCI_HOST_BRIDGE(obj);
207     I440FXState *s = I440FX_PCI_HOST_BRIDGE(obj);
208     uint64_t hole64_start = i440fx_pcihost_get_pci_hole64_start_value(obj);
209     Range w64;
210     uint64_t value, hole64_end;
211 
212     pci_bus_get_w64_range(h->bus, &w64);
213     value = range_is_empty(&w64) ? 0 : range_upb(&w64) + 1;
214     hole64_end = ROUND_UP(hole64_start + s->pci_hole64_size, 1ULL << 30);
215     if (s->pci_hole64_fix && value < hole64_end) {
216         value = hole64_end;
217     }
218     visit_type_uint64(v, name, &value, errp);
219 }
220 
221 static void i440fx_pcihost_initfn(Object *obj)
222 {
223     PCIHostState *s = PCI_HOST_BRIDGE(obj);
224 
225     memory_region_init_io(&s->conf_mem, obj, &pci_host_conf_le_ops, s,
226                           "pci-conf-idx", 4);
227     memory_region_init_io(&s->data_mem, obj, &pci_host_data_le_ops, s,
228                           "pci-conf-data", 4);
229 
230     object_property_add(obj, PCI_HOST_PROP_PCI_HOLE_START, "uint32",
231                         i440fx_pcihost_get_pci_hole_start,
232                         NULL, NULL, NULL, NULL);
233 
234     object_property_add(obj, PCI_HOST_PROP_PCI_HOLE_END, "uint32",
235                         i440fx_pcihost_get_pci_hole_end,
236                         NULL, NULL, NULL, NULL);
237 
238     object_property_add(obj, PCI_HOST_PROP_PCI_HOLE64_START, "uint64",
239                         i440fx_pcihost_get_pci_hole64_start,
240                         NULL, NULL, NULL, NULL);
241 
242     object_property_add(obj, PCI_HOST_PROP_PCI_HOLE64_END, "uint64",
243                         i440fx_pcihost_get_pci_hole64_end,
244                         NULL, NULL, NULL, NULL);
245 }
246 
247 static void i440fx_pcihost_realize(DeviceState *dev, Error **errp)
248 {
249     PCIHostState *s = PCI_HOST_BRIDGE(dev);
250     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
251 
252     sysbus_add_io(sbd, 0xcf8, &s->conf_mem);
253     sysbus_init_ioports(sbd, 0xcf8, 4);
254 
255     sysbus_add_io(sbd, 0xcfc, &s->data_mem);
256     sysbus_init_ioports(sbd, 0xcfc, 4);
257 
258     /* register i440fx 0xcf8 port as coalesced pio */
259     memory_region_set_flush_coalesced(&s->data_mem);
260     memory_region_add_coalescing(&s->conf_mem, 0, 4);
261 }
262 
263 static void i440fx_realize(PCIDevice *dev, Error **errp)
264 {
265     dev->config[I440FX_SMRAM] = 0x02;
266 
267     if (object_property_get_bool(qdev_get_machine(), "iommu", NULL)) {
268         warn_report("i440fx doesn't support emulated iommu");
269     }
270 }
271 
272 PCIBus *i440fx_init(const char *host_type, const char *pci_type,
273                     PCII440FXState **pi440fx_state,
274                     MemoryRegion *address_space_mem,
275                     MemoryRegion *address_space_io,
276                     ram_addr_t ram_size,
277                     ram_addr_t below_4g_mem_size,
278                     ram_addr_t above_4g_mem_size,
279                     MemoryRegion *pci_address_space,
280                     MemoryRegion *ram_memory)
281 {
282     DeviceState *dev;
283     PCIBus *b;
284     PCIDevice *d;
285     PCIHostState *s;
286     PCII440FXState *f;
287     unsigned i;
288     I440FXState *i440fx;
289 
290     dev = qdev_create(NULL, host_type);
291     s = PCI_HOST_BRIDGE(dev);
292     b = pci_root_bus_new(dev, NULL, pci_address_space,
293                          address_space_io, 0, TYPE_PCI_BUS);
294     s->bus = b;
295     object_property_add_child(qdev_get_machine(), "i440fx", OBJECT(dev), NULL);
296     qdev_init_nofail(dev);
297 
298     d = pci_create_simple(b, 0, pci_type);
299     *pi440fx_state = I440FX_PCI_DEVICE(d);
300     f = *pi440fx_state;
301     f->system_memory = address_space_mem;
302     f->pci_address_space = pci_address_space;
303     f->ram_memory = ram_memory;
304 
305     i440fx = I440FX_PCI_HOST_BRIDGE(dev);
306     range_set_bounds(&i440fx->pci_hole, below_4g_mem_size,
307                      IO_APIC_DEFAULT_ADDRESS - 1);
308 
309     /* setup pci memory mapping */
310     pc_pci_as_mapping_init(OBJECT(f), f->system_memory,
311                            f->pci_address_space);
312 
313     /* if *disabled* show SMRAM to all CPUs */
314     memory_region_init_alias(&f->smram_region, OBJECT(d), "smram-region",
315                              f->pci_address_space, 0xa0000, 0x20000);
316     memory_region_add_subregion_overlap(f->system_memory, 0xa0000,
317                                         &f->smram_region, 1);
318     memory_region_set_enabled(&f->smram_region, true);
319 
320     /* smram, as seen by SMM CPUs */
321     memory_region_init(&f->smram, OBJECT(d), "smram", 1ull << 32);
322     memory_region_set_enabled(&f->smram, true);
323     memory_region_init_alias(&f->low_smram, OBJECT(d), "smram-low",
324                              f->ram_memory, 0xa0000, 0x20000);
325     memory_region_set_enabled(&f->low_smram, true);
326     memory_region_add_subregion(&f->smram, 0xa0000, &f->low_smram);
327     object_property_add_const_link(qdev_get_machine(), "smram",
328                                    OBJECT(&f->smram), &error_abort);
329 
330     init_pam(dev, f->ram_memory, f->system_memory, f->pci_address_space,
331              &f->pam_regions[0], PAM_BIOS_BASE, PAM_BIOS_SIZE);
332     for (i = 0; i < ARRAY_SIZE(f->pam_regions) - 1; ++i) {
333         init_pam(dev, f->ram_memory, f->system_memory, f->pci_address_space,
334                  &f->pam_regions[i+1], PAM_EXPAN_BASE + i * PAM_EXPAN_SIZE,
335                  PAM_EXPAN_SIZE);
336     }
337 
338     ram_size = ram_size / 8 / 1024 / 1024;
339     if (ram_size > 255) {
340         ram_size = 255;
341     }
342     d->config[I440FX_COREBOOT_RAM_SIZE] = ram_size;
343 
344     i440fx_update_memory_mappings(f);
345 
346     return b;
347 }
348 
349 PCIBus *find_i440fx(void)
350 {
351     PCIHostState *s = OBJECT_CHECK(PCIHostState,
352                                    object_resolve_path("/machine/i440fx", NULL),
353                                    TYPE_PCI_HOST_BRIDGE);
354     return s ? s->bus : NULL;
355 }
356 
357 static void i440fx_class_init(ObjectClass *klass, void *data)
358 {
359     DeviceClass *dc = DEVICE_CLASS(klass);
360     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
361 
362     k->realize = i440fx_realize;
363     k->config_write = i440fx_write_config;
364     k->vendor_id = PCI_VENDOR_ID_INTEL;
365     k->device_id = PCI_DEVICE_ID_INTEL_82441;
366     k->revision = 0x02;
367     k->class_id = PCI_CLASS_BRIDGE_HOST;
368     dc->desc = "Host bridge";
369     dc->vmsd = &vmstate_i440fx;
370     /*
371      * PCI-facing part of the host bridge, not usable without the
372      * host-facing part, which can't be device_add'ed, yet.
373      */
374     dc->user_creatable = false;
375     dc->hotpluggable   = false;
376 }
377 
378 static const TypeInfo i440fx_info = {
379     .name          = TYPE_I440FX_PCI_DEVICE,
380     .parent        = TYPE_PCI_DEVICE,
381     .instance_size = sizeof(PCII440FXState),
382     .class_init    = i440fx_class_init,
383     .interfaces = (InterfaceInfo[]) {
384         { INTERFACE_CONVENTIONAL_PCI_DEVICE },
385         { },
386     },
387 };
388 
389 /* IGD Passthrough Host Bridge. */
390 typedef struct {
391     uint8_t offset;
392     uint8_t len;
393 } IGDHostInfo;
394 
395 /* Here we just expose minimal host bridge offset subset. */
396 static const IGDHostInfo igd_host_bridge_infos[] = {
397     {0x08, 2},  /* revision id */
398     {0x2c, 2},  /* sybsystem vendor id */
399     {0x2e, 2},  /* sybsystem id */
400     {0x50, 2},  /* SNB: processor graphics control register */
401     {0x52, 2},  /* processor graphics control register */
402     {0xa4, 4},  /* SNB: graphics base of stolen memory */
403     {0xa8, 4},  /* SNB: base of GTT stolen memory */
404 };
405 
406 static void host_pci_config_read(int pos, int len, uint32_t *val, Error **errp)
407 {
408     int rc, config_fd;
409     /* Access real host bridge. */
410     char *path = g_strdup_printf("/sys/bus/pci/devices/%04x:%02x:%02x.%d/%s",
411                                  0, 0, 0, 0, "config");
412 
413     config_fd = open(path, O_RDWR);
414     if (config_fd < 0) {
415         error_setg_errno(errp, errno, "Failed to open: %s", path);
416         goto out;
417     }
418 
419     if (lseek(config_fd, pos, SEEK_SET) != pos) {
420         error_setg_errno(errp, errno, "Failed to seek: %s", path);
421         goto out_close_fd;
422     }
423 
424     do {
425         rc = read(config_fd, (uint8_t *)val, len);
426     } while (rc < 0 && (errno == EINTR || errno == EAGAIN));
427     if (rc != len) {
428         error_setg_errno(errp, errno, "Failed to read: %s", path);
429     }
430 
431 out_close_fd:
432     close(config_fd);
433 out:
434     g_free(path);
435 }
436 
437 static void igd_pt_i440fx_realize(PCIDevice *pci_dev, Error **errp)
438 {
439     uint32_t val = 0;
440     int i, num;
441     int pos, len;
442     Error *local_err = NULL;
443 
444     num = ARRAY_SIZE(igd_host_bridge_infos);
445     for (i = 0; i < num; i++) {
446         pos = igd_host_bridge_infos[i].offset;
447         len = igd_host_bridge_infos[i].len;
448         host_pci_config_read(pos, len, &val, &local_err);
449         if (local_err) {
450             error_propagate(errp, local_err);
451             return;
452         }
453         pci_default_write_config(pci_dev, pos, val, len);
454     }
455 }
456 
457 static void igd_passthrough_i440fx_class_init(ObjectClass *klass, void *data)
458 {
459     DeviceClass *dc = DEVICE_CLASS(klass);
460     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
461 
462     k->realize = igd_pt_i440fx_realize;
463     dc->desc = "IGD Passthrough Host bridge";
464 }
465 
466 static const TypeInfo igd_passthrough_i440fx_info = {
467     .name          = TYPE_IGD_PASSTHROUGH_I440FX_PCI_DEVICE,
468     .parent        = TYPE_I440FX_PCI_DEVICE,
469     .instance_size = sizeof(PCII440FXState),
470     .class_init    = igd_passthrough_i440fx_class_init,
471 };
472 
473 static const char *i440fx_pcihost_root_bus_path(PCIHostState *host_bridge,
474                                                 PCIBus *rootbus)
475 {
476     I440FXState *s = I440FX_PCI_HOST_BRIDGE(host_bridge);
477 
478     /* For backwards compat with old device paths */
479     if (s->short_root_bus) {
480         return "0000";
481     }
482     return "0000:00";
483 }
484 
485 static Property i440fx_props[] = {
486     DEFINE_PROP_SIZE(PCI_HOST_PROP_PCI_HOLE64_SIZE, I440FXState,
487                      pci_hole64_size, I440FX_PCI_HOST_HOLE64_SIZE_DEFAULT),
488     DEFINE_PROP_UINT32("short_root_bus", I440FXState, short_root_bus, 0),
489     DEFINE_PROP_BOOL("x-pci-hole64-fix", I440FXState, pci_hole64_fix, true),
490     DEFINE_PROP_END_OF_LIST(),
491 };
492 
493 static void i440fx_pcihost_class_init(ObjectClass *klass, void *data)
494 {
495     DeviceClass *dc = DEVICE_CLASS(klass);
496     PCIHostBridgeClass *hc = PCI_HOST_BRIDGE_CLASS(klass);
497 
498     hc->root_bus_path = i440fx_pcihost_root_bus_path;
499     dc->realize = i440fx_pcihost_realize;
500     dc->fw_name = "pci";
501     dc->props = i440fx_props;
502     /* Reason: needs to be wired up by pc_init1 */
503     dc->user_creatable = false;
504 }
505 
506 static const TypeInfo i440fx_pcihost_info = {
507     .name          = TYPE_I440FX_PCI_HOST_BRIDGE,
508     .parent        = TYPE_PCI_HOST_BRIDGE,
509     .instance_size = sizeof(I440FXState),
510     .instance_init = i440fx_pcihost_initfn,
511     .class_init    = i440fx_pcihost_class_init,
512 };
513 
514 static void i440fx_register_types(void)
515 {
516     type_register_static(&i440fx_info);
517     type_register_static(&igd_passthrough_i440fx_info);
518     type_register_static(&i440fx_pcihost_info);
519 }
520 
521 type_init(i440fx_register_types)
522