xref: /openbmc/qemu/hw/pci/pci_bridge.c (revision 40d6ee94)
1 /*
2  * QEMU PCI bus manager
3  *
4  * Copyright (c) 2004 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 dea
8 
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM
22 
23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24  * THE SOFTWARE.
25  */
26 /*
27  * split out from pci.c
28  * Copyright (c) 2010 Isaku Yamahata <yamahata at valinux co jp>
29  *                    VA Linux Systems Japan K.K.
30  */
31 
32 #include "qemu/osdep.h"
33 #include "hw/pci/pci_bridge.h"
34 #include "hw/pci/pci_bus.h"
35 #include "qemu/range.h"
36 #include "qapi/error.h"
37 
38 /* PCI bridge subsystem vendor ID helper functions */
39 #define PCI_SSVID_SIZEOF        8
40 #define PCI_SSVID_SVID          4
41 #define PCI_SSVID_SSID          6
42 
43 int pci_bridge_ssvid_init(PCIDevice *dev, uint8_t offset,
44                           uint16_t svid, uint16_t ssid,
45                           Error **errp)
46 {
47     int pos;
48 
49     pos = pci_add_capability(dev, PCI_CAP_ID_SSVID, offset,
50                              PCI_SSVID_SIZEOF, errp);
51     if (pos < 0) {
52         return pos;
53     }
54 
55     pci_set_word(dev->config + pos + PCI_SSVID_SVID, svid);
56     pci_set_word(dev->config + pos + PCI_SSVID_SSID, ssid);
57     return pos;
58 }
59 
60 /* Accessor function to get parent bridge device from pci bus. */
61 PCIDevice *pci_bridge_get_device(PCIBus *bus)
62 {
63     return bus->parent_dev;
64 }
65 
66 /* Accessor function to get secondary bus from pci-to-pci bridge device */
67 PCIBus *pci_bridge_get_sec_bus(PCIBridge *br)
68 {
69     return &br->sec_bus;
70 }
71 
72 static uint32_t pci_config_get_io_base(const PCIDevice *d,
73                                        uint32_t base, uint32_t base_upper16)
74 {
75     uint32_t val;
76 
77     val = ((uint32_t)d->config[base] & PCI_IO_RANGE_MASK) << 8;
78     if (d->config[base] & PCI_IO_RANGE_TYPE_32) {
79         val |= (uint32_t)pci_get_word(d->config + base_upper16) << 16;
80     }
81     return val;
82 }
83 
84 static pcibus_t pci_config_get_memory_base(const PCIDevice *d, uint32_t base)
85 {
86     return ((pcibus_t)pci_get_word(d->config + base) & PCI_MEMORY_RANGE_MASK)
87         << 16;
88 }
89 
90 static pcibus_t pci_config_get_pref_base(const PCIDevice *d,
91                                          uint32_t base, uint32_t upper)
92 {
93     pcibus_t tmp;
94     pcibus_t val;
95 
96     tmp = (pcibus_t)pci_get_word(d->config + base);
97     val = (tmp & PCI_PREF_RANGE_MASK) << 16;
98     if (tmp & PCI_PREF_RANGE_TYPE_64) {
99         val |= (pcibus_t)pci_get_long(d->config + upper) << 32;
100     }
101     return val;
102 }
103 
104 /* accessor function to get bridge filtering base address */
105 pcibus_t pci_bridge_get_base(const PCIDevice *bridge, uint8_t type)
106 {
107     pcibus_t base;
108     if (type & PCI_BASE_ADDRESS_SPACE_IO) {
109         base = pci_config_get_io_base(bridge,
110                                       PCI_IO_BASE, PCI_IO_BASE_UPPER16);
111     } else {
112         if (type & PCI_BASE_ADDRESS_MEM_PREFETCH) {
113             base = pci_config_get_pref_base(
114                 bridge, PCI_PREF_MEMORY_BASE, PCI_PREF_BASE_UPPER32);
115         } else {
116             base = pci_config_get_memory_base(bridge, PCI_MEMORY_BASE);
117         }
118     }
119 
120     return base;
121 }
122 
123 /* accessor function to get bridge filtering limit */
124 pcibus_t pci_bridge_get_limit(const PCIDevice *bridge, uint8_t type)
125 {
126     pcibus_t limit;
127     if (type & PCI_BASE_ADDRESS_SPACE_IO) {
128         limit = pci_config_get_io_base(bridge,
129                                       PCI_IO_LIMIT, PCI_IO_LIMIT_UPPER16);
130         limit |= 0xfff;         /* PCI bridge spec 3.2.5.6. */
131     } else {
132         if (type & PCI_BASE_ADDRESS_MEM_PREFETCH) {
133             limit = pci_config_get_pref_base(
134                 bridge, PCI_PREF_MEMORY_LIMIT, PCI_PREF_LIMIT_UPPER32);
135         } else {
136             limit = pci_config_get_memory_base(bridge, PCI_MEMORY_LIMIT);
137         }
138         limit |= 0xfffff;       /* PCI bridge spec 3.2.5.{1, 8}. */
139     }
140     return limit;
141 }
142 
143 static void pci_bridge_init_alias(PCIBridge *bridge, MemoryRegion *alias,
144                                   uint8_t type, const char *name,
145                                   MemoryRegion *space,
146                                   MemoryRegion *parent_space,
147                                   bool enabled)
148 {
149     PCIDevice *bridge_dev = PCI_DEVICE(bridge);
150     pcibus_t base = pci_bridge_get_base(bridge_dev, type);
151     pcibus_t limit = pci_bridge_get_limit(bridge_dev, type);
152     /* TODO: this doesn't handle base = 0 limit = 2^64 - 1 correctly.
153      * Apparently no way to do this with existing memory APIs. */
154     pcibus_t size = enabled && limit >= base ? limit + 1 - base : 0;
155 
156     memory_region_init_alias(alias, OBJECT(bridge), name, space, base, size);
157     memory_region_add_subregion_overlap(parent_space, base, alias, 1);
158 }
159 
160 static void pci_bridge_init_vga_aliases(PCIBridge *br, PCIBus *parent,
161                                         MemoryRegion *alias_vga)
162 {
163     PCIDevice *pd = PCI_DEVICE(br);
164     uint16_t brctl = pci_get_word(pd->config + PCI_BRIDGE_CONTROL);
165 
166     memory_region_init_alias(&alias_vga[QEMU_PCI_VGA_IO_LO], OBJECT(br),
167                              "pci_bridge_vga_io_lo", &br->address_space_io,
168                              QEMU_PCI_VGA_IO_LO_BASE, QEMU_PCI_VGA_IO_LO_SIZE);
169     memory_region_init_alias(&alias_vga[QEMU_PCI_VGA_IO_HI], OBJECT(br),
170                              "pci_bridge_vga_io_hi", &br->address_space_io,
171                              QEMU_PCI_VGA_IO_HI_BASE, QEMU_PCI_VGA_IO_HI_SIZE);
172     memory_region_init_alias(&alias_vga[QEMU_PCI_VGA_MEM], OBJECT(br),
173                              "pci_bridge_vga_mem", &br->address_space_mem,
174                              QEMU_PCI_VGA_MEM_BASE, QEMU_PCI_VGA_MEM_SIZE);
175 
176     if (brctl & PCI_BRIDGE_CTL_VGA) {
177         pci_register_vga(pd, &alias_vga[QEMU_PCI_VGA_MEM],
178                          &alias_vga[QEMU_PCI_VGA_IO_LO],
179                          &alias_vga[QEMU_PCI_VGA_IO_HI]);
180     }
181 }
182 
183 static PCIBridgeWindows *pci_bridge_region_init(PCIBridge *br)
184 {
185     PCIDevice *pd = PCI_DEVICE(br);
186     PCIBus *parent = pci_get_bus(pd);
187     PCIBridgeWindows *w = g_new(PCIBridgeWindows, 1);
188     uint16_t cmd = pci_get_word(pd->config + PCI_COMMAND);
189 
190     pci_bridge_init_alias(br, &w->alias_pref_mem,
191                           PCI_BASE_ADDRESS_MEM_PREFETCH,
192                           "pci_bridge_pref_mem",
193                           &br->address_space_mem,
194                           parent->address_space_mem,
195                           cmd & PCI_COMMAND_MEMORY);
196     pci_bridge_init_alias(br, &w->alias_mem,
197                           PCI_BASE_ADDRESS_SPACE_MEMORY,
198                           "pci_bridge_mem",
199                           &br->address_space_mem,
200                           parent->address_space_mem,
201                           cmd & PCI_COMMAND_MEMORY);
202     pci_bridge_init_alias(br, &w->alias_io,
203                           PCI_BASE_ADDRESS_SPACE_IO,
204                           "pci_bridge_io",
205                           &br->address_space_io,
206                           parent->address_space_io,
207                           cmd & PCI_COMMAND_IO);
208 
209     pci_bridge_init_vga_aliases(br, parent, w->alias_vga);
210 
211     return w;
212 }
213 
214 static void pci_bridge_region_del(PCIBridge *br, PCIBridgeWindows *w)
215 {
216     PCIDevice *pd = PCI_DEVICE(br);
217     PCIBus *parent = pci_get_bus(pd);
218 
219     memory_region_del_subregion(parent->address_space_io, &w->alias_io);
220     memory_region_del_subregion(parent->address_space_mem, &w->alias_mem);
221     memory_region_del_subregion(parent->address_space_mem, &w->alias_pref_mem);
222     pci_unregister_vga(pd);
223 }
224 
225 static void pci_bridge_region_cleanup(PCIBridge *br, PCIBridgeWindows *w)
226 {
227     object_unparent(OBJECT(&w->alias_io));
228     object_unparent(OBJECT(&w->alias_mem));
229     object_unparent(OBJECT(&w->alias_pref_mem));
230     object_unparent(OBJECT(&w->alias_vga[QEMU_PCI_VGA_IO_LO]));
231     object_unparent(OBJECT(&w->alias_vga[QEMU_PCI_VGA_IO_HI]));
232     object_unparent(OBJECT(&w->alias_vga[QEMU_PCI_VGA_MEM]));
233     g_free(w);
234 }
235 
236 void pci_bridge_update_mappings(PCIBridge *br)
237 {
238     PCIBridgeWindows *w = br->windows;
239 
240     /* Make updates atomic to: handle the case of one VCPU updating the bridge
241      * while another accesses an unaffected region. */
242     memory_region_transaction_begin();
243     pci_bridge_region_del(br, br->windows);
244     pci_bridge_region_cleanup(br, w);
245     br->windows = pci_bridge_region_init(br);
246     memory_region_transaction_commit();
247 }
248 
249 /* default write_config function for PCI-to-PCI bridge */
250 void pci_bridge_write_config(PCIDevice *d,
251                              uint32_t address, uint32_t val, int len)
252 {
253     PCIBridge *s = PCI_BRIDGE(d);
254     uint16_t oldctl = pci_get_word(d->config + PCI_BRIDGE_CONTROL);
255     uint16_t newctl;
256 
257     pci_default_write_config(d, address, val, len);
258 
259     if (ranges_overlap(address, len, PCI_COMMAND, 2) ||
260 
261         /* io base/limit */
262         ranges_overlap(address, len, PCI_IO_BASE, 2) ||
263 
264         /* memory base/limit, prefetchable base/limit and
265            io base/limit upper 16 */
266         ranges_overlap(address, len, PCI_MEMORY_BASE, 20) ||
267 
268         /* vga enable */
269         ranges_overlap(address, len, PCI_BRIDGE_CONTROL, 2)) {
270         pci_bridge_update_mappings(s);
271     }
272 
273     newctl = pci_get_word(d->config + PCI_BRIDGE_CONTROL);
274     if (~oldctl & newctl & PCI_BRIDGE_CTL_BUS_RESET) {
275         /* Trigger hot reset on 0->1 transition. */
276         qbus_reset_all(&s->sec_bus.qbus);
277     }
278 }
279 
280 void pci_bridge_disable_base_limit(PCIDevice *dev)
281 {
282     uint8_t *conf = dev->config;
283 
284     pci_byte_test_and_set_mask(conf + PCI_IO_BASE,
285                                PCI_IO_RANGE_MASK & 0xff);
286     pci_byte_test_and_clear_mask(conf + PCI_IO_LIMIT,
287                                  PCI_IO_RANGE_MASK & 0xff);
288     pci_word_test_and_set_mask(conf + PCI_MEMORY_BASE,
289                                PCI_MEMORY_RANGE_MASK & 0xffff);
290     pci_word_test_and_clear_mask(conf + PCI_MEMORY_LIMIT,
291                                  PCI_MEMORY_RANGE_MASK & 0xffff);
292     pci_word_test_and_set_mask(conf + PCI_PREF_MEMORY_BASE,
293                                PCI_PREF_RANGE_MASK & 0xffff);
294     pci_word_test_and_clear_mask(conf + PCI_PREF_MEMORY_LIMIT,
295                                  PCI_PREF_RANGE_MASK & 0xffff);
296     pci_set_long(conf + PCI_PREF_BASE_UPPER32, 0);
297     pci_set_long(conf + PCI_PREF_LIMIT_UPPER32, 0);
298 }
299 
300 /* reset bridge specific configuration registers */
301 void pci_bridge_reset(DeviceState *qdev)
302 {
303     PCIDevice *dev = PCI_DEVICE(qdev);
304     uint8_t *conf = dev->config;
305 
306     conf[PCI_PRIMARY_BUS] = 0;
307     conf[PCI_SECONDARY_BUS] = 0;
308     conf[PCI_SUBORDINATE_BUS] = 0;
309     conf[PCI_SEC_LATENCY_TIMER] = 0;
310 
311     /*
312      * the default values for base/limit registers aren't specified
313      * in the PCI-to-PCI-bridge spec. So we don't thouch them here.
314      * Each implementation can override it.
315      * typical implementation does
316      * zero base/limit registers or
317      * disable forwarding: pci_bridge_disable_base_limit()
318      * If disable forwarding is wanted, call pci_bridge_disable_base_limit()
319      * after this function.
320      */
321     pci_byte_test_and_clear_mask(conf + PCI_IO_BASE,
322                                  PCI_IO_RANGE_MASK & 0xff);
323     pci_byte_test_and_clear_mask(conf + PCI_IO_LIMIT,
324                                  PCI_IO_RANGE_MASK & 0xff);
325     pci_word_test_and_clear_mask(conf + PCI_MEMORY_BASE,
326                                  PCI_MEMORY_RANGE_MASK & 0xffff);
327     pci_word_test_and_clear_mask(conf + PCI_MEMORY_LIMIT,
328                                  PCI_MEMORY_RANGE_MASK & 0xffff);
329     pci_word_test_and_clear_mask(conf + PCI_PREF_MEMORY_BASE,
330                                  PCI_PREF_RANGE_MASK & 0xffff);
331     pci_word_test_and_clear_mask(conf + PCI_PREF_MEMORY_LIMIT,
332                                  PCI_PREF_RANGE_MASK & 0xffff);
333     pci_set_long(conf + PCI_PREF_BASE_UPPER32, 0);
334     pci_set_long(conf + PCI_PREF_LIMIT_UPPER32, 0);
335 
336     pci_set_word(conf + PCI_BRIDGE_CONTROL, 0);
337 }
338 
339 /* default qdev initialization function for PCI-to-PCI bridge */
340 void pci_bridge_initfn(PCIDevice *dev, const char *typename)
341 {
342     PCIBus *parent = pci_get_bus(dev);
343     PCIBridge *br = PCI_BRIDGE(dev);
344     PCIBus *sec_bus = &br->sec_bus;
345 
346     pci_word_test_and_set_mask(dev->config + PCI_STATUS,
347                                PCI_STATUS_66MHZ | PCI_STATUS_FAST_BACK);
348 
349     /*
350      * TODO: We implement VGA Enable in the Bridge Control Register
351      * therefore per the PCI to PCI bridge spec we must also implement
352      * VGA Palette Snooping.  When done, set this bit writable:
353      *
354      * pci_word_test_and_set_mask(dev->wmask + PCI_COMMAND,
355      *                            PCI_COMMAND_VGA_PALETTE);
356      */
357 
358     pci_config_set_class(dev->config, PCI_CLASS_BRIDGE_PCI);
359     dev->config[PCI_HEADER_TYPE] =
360         (dev->config[PCI_HEADER_TYPE] & PCI_HEADER_TYPE_MULTI_FUNCTION) |
361         PCI_HEADER_TYPE_BRIDGE;
362     pci_set_word(dev->config + PCI_SEC_STATUS,
363                  PCI_STATUS_66MHZ | PCI_STATUS_FAST_BACK);
364 
365     /*
366      * If we don't specify the name, the bus will be addressed as <id>.0, where
367      * id is the device id.
368      * Since PCI Bridge devices have a single bus each, we don't need the index:
369      * let users address the bus using the device name.
370      */
371     if (!br->bus_name && dev->qdev.id && *dev->qdev.id) {
372             br->bus_name = dev->qdev.id;
373     }
374 
375     qbus_create_inplace(sec_bus, sizeof(br->sec_bus), typename, DEVICE(dev),
376                         br->bus_name);
377     sec_bus->parent_dev = dev;
378     sec_bus->map_irq = br->map_irq ? br->map_irq : pci_swizzle_map_irq_fn;
379     sec_bus->address_space_mem = &br->address_space_mem;
380     memory_region_init(&br->address_space_mem, OBJECT(br), "pci_bridge_pci", UINT64_MAX);
381     sec_bus->address_space_io = &br->address_space_io;
382     memory_region_init(&br->address_space_io, OBJECT(br), "pci_bridge_io",
383                        UINT32_MAX);
384     br->windows = pci_bridge_region_init(br);
385     QLIST_INIT(&sec_bus->child);
386     QLIST_INSERT_HEAD(&parent->child, sec_bus, sibling);
387 }
388 
389 /* default qdev clean up function for PCI-to-PCI bridge */
390 void pci_bridge_exitfn(PCIDevice *pci_dev)
391 {
392     PCIBridge *s = PCI_BRIDGE(pci_dev);
393     assert(QLIST_EMPTY(&s->sec_bus.child));
394     QLIST_REMOVE(&s->sec_bus, sibling);
395     pci_bridge_region_del(s, s->windows);
396     pci_bridge_region_cleanup(s, s->windows);
397     /* object_unparent() is called automatically during device deletion */
398 }
399 
400 /*
401  * before qdev initialization(qdev_init()), this function sets bus_name and
402  * map_irq callback which are necessary for pci_bridge_initfn() to
403  * initialize bus.
404  */
405 void pci_bridge_map_irq(PCIBridge *br, const char* bus_name,
406                         pci_map_irq_fn map_irq)
407 {
408     br->map_irq = map_irq;
409     br->bus_name = bus_name;
410 }
411 
412 
413 int pci_bridge_qemu_reserve_cap_init(PCIDevice *dev, int cap_offset,
414                                      PCIResReserve res_reserve, Error **errp)
415 {
416     if (res_reserve.mem_pref_32 != (uint64_t)-1 &&
417         res_reserve.mem_pref_64 != (uint64_t)-1) {
418         error_setg(errp,
419                    "PCI resource reserve cap: PREF32 and PREF64 conflict");
420         return -EINVAL;
421     }
422 
423     if (res_reserve.mem_non_pref != (uint64_t)-1 &&
424         res_reserve.mem_non_pref >= (1ULL << 32)) {
425         error_setg(errp,
426                    "PCI resource reserve cap: mem-reserve must be less than 4G");
427         return -EINVAL;
428     }
429 
430     if (res_reserve.mem_pref_32 != (uint64_t)-1 &&
431         res_reserve.mem_pref_32 >= (1ULL << 32)) {
432         error_setg(errp,
433                    "PCI resource reserve cap: pref32-reserve  must be less than 4G");
434         return -EINVAL;
435     }
436 
437     if (res_reserve.bus == (uint32_t)-1 &&
438         res_reserve.io == (uint64_t)-1 &&
439         res_reserve.mem_non_pref == (uint64_t)-1 &&
440         res_reserve.mem_pref_32 == (uint64_t)-1 &&
441         res_reserve.mem_pref_64 == (uint64_t)-1) {
442         return 0;
443     }
444 
445     size_t cap_len = sizeof(PCIBridgeQemuCap);
446     PCIBridgeQemuCap cap = {
447             .len = cap_len,
448             .type = REDHAT_PCI_CAP_RESOURCE_RESERVE,
449             .bus_res = res_reserve.bus,
450             .io = res_reserve.io,
451             .mem = res_reserve.mem_non_pref,
452             .mem_pref_32 = res_reserve.mem_pref_32,
453             .mem_pref_64 = res_reserve.mem_pref_64
454     };
455 
456     int offset = pci_add_capability(dev, PCI_CAP_ID_VNDR,
457                                     cap_offset, cap_len, errp);
458     if (offset < 0) {
459         return offset;
460     }
461 
462     memcpy(dev->config + offset + PCI_CAP_FLAGS,
463            (char *)&cap + PCI_CAP_FLAGS,
464            cap_len - PCI_CAP_FLAGS);
465     return 0;
466 }
467 
468 static const TypeInfo pci_bridge_type_info = {
469     .name = TYPE_PCI_BRIDGE,
470     .parent = TYPE_PCI_DEVICE,
471     .instance_size = sizeof(PCIBridge),
472     .abstract = true,
473 };
474 
475 static void pci_bridge_register_types(void)
476 {
477     type_register_static(&pci_bridge_type_info);
478 }
479 
480 type_init(pci_bridge_register_types)
481