xref: /qemu/hw/isa/piix.c (revision da278d58a092bfcc4e36f1e274229c1468dea731)
1 /*
2  * QEMU PIIX PCI ISA 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 "qemu/range.h"
27 #include "hw/southbridge/piix.h"
28 #include "hw/irq.h"
29 #include "hw/isa/isa.h"
30 #include "hw/xen/xen.h"
31 #include "sysemu/xen.h"
32 #include "sysemu/sysemu.h"
33 #include "sysemu/reset.h"
34 #include "sysemu/runstate.h"
35 #include "migration/vmstate.h"
36 
37 #define XEN_PIIX_NUM_PIRQS      128ULL
38 
39 #define TYPE_PIIX3_PCI_DEVICE "pci-piix3"
40 #define PIIX3_PCI_DEVICE(obj) \
41     OBJECT_CHECK(PIIX3State, (obj), TYPE_PIIX3_PCI_DEVICE)
42 
43 #define TYPE_PIIX3_DEVICE "PIIX3"
44 #define TYPE_PIIX3_XEN_DEVICE "PIIX3-xen"
45 
46 static void piix3_set_irq_pic(PIIX3State *piix3, int pic_irq)
47 {
48     qemu_set_irq(piix3->pic[pic_irq],
49                  !!(piix3->pic_levels &
50                     (((1ULL << PIIX_NUM_PIRQS) - 1) <<
51                      (pic_irq * PIIX_NUM_PIRQS))));
52 }
53 
54 static void piix3_set_irq_level_internal(PIIX3State *piix3, int pirq, int level)
55 {
56     int pic_irq;
57     uint64_t mask;
58 
59     pic_irq = piix3->dev.config[PIIX_PIRQCA + pirq];
60     if (pic_irq >= PIIX_NUM_PIC_IRQS) {
61         return;
62     }
63 
64     mask = 1ULL << ((pic_irq * PIIX_NUM_PIRQS) + pirq);
65     piix3->pic_levels &= ~mask;
66     piix3->pic_levels |= mask * !!level;
67 }
68 
69 static void piix3_set_irq_level(PIIX3State *piix3, int pirq, int level)
70 {
71     int pic_irq;
72 
73     pic_irq = piix3->dev.config[PIIX_PIRQCA + pirq];
74     if (pic_irq >= PIIX_NUM_PIC_IRQS) {
75         return;
76     }
77 
78     piix3_set_irq_level_internal(piix3, pirq, level);
79 
80     piix3_set_irq_pic(piix3, pic_irq);
81 }
82 
83 static void piix3_set_irq(void *opaque, int pirq, int level)
84 {
85     PIIX3State *piix3 = opaque;
86     piix3_set_irq_level(piix3, pirq, level);
87 }
88 
89 static PCIINTxRoute piix3_route_intx_pin_to_irq(void *opaque, int pin)
90 {
91     PIIX3State *piix3 = opaque;
92     int irq = piix3->dev.config[PIIX_PIRQCA + pin];
93     PCIINTxRoute route;
94 
95     if (irq < PIIX_NUM_PIC_IRQS) {
96         route.mode = PCI_INTX_ENABLED;
97         route.irq = irq;
98     } else {
99         route.mode = PCI_INTX_DISABLED;
100         route.irq = -1;
101     }
102     return route;
103 }
104 
105 /* irq routing is changed. so rebuild bitmap */
106 static void piix3_update_irq_levels(PIIX3State *piix3)
107 {
108     PCIBus *bus = pci_get_bus(&piix3->dev);
109     int pirq;
110 
111     piix3->pic_levels = 0;
112     for (pirq = 0; pirq < PIIX_NUM_PIRQS; pirq++) {
113         piix3_set_irq_level(piix3, pirq, pci_bus_get_irq_level(bus, pirq));
114     }
115 }
116 
117 static void piix3_write_config(PCIDevice *dev,
118                                uint32_t address, uint32_t val, int len)
119 {
120     pci_default_write_config(dev, address, val, len);
121     if (ranges_overlap(address, len, PIIX_PIRQCA, 4)) {
122         PIIX3State *piix3 = PIIX3_PCI_DEVICE(dev);
123         int pic_irq;
124 
125         pci_bus_fire_intx_routing_notifier(pci_get_bus(&piix3->dev));
126         piix3_update_irq_levels(piix3);
127         for (pic_irq = 0; pic_irq < PIIX_NUM_PIC_IRQS; pic_irq++) {
128             piix3_set_irq_pic(piix3, pic_irq);
129         }
130     }
131 }
132 
133 static void piix3_write_config_xen(PCIDevice *dev,
134                                    uint32_t address, uint32_t val, int len)
135 {
136     xen_piix_pci_write_config_client(address, val, len);
137     piix3_write_config(dev, address, val, len);
138 }
139 
140 static void piix3_reset(void *opaque)
141 {
142     PIIX3State *d = opaque;
143     uint8_t *pci_conf = d->dev.config;
144 
145     pci_conf[0x04] = 0x07; /* master, memory and I/O */
146     pci_conf[0x05] = 0x00;
147     pci_conf[0x06] = 0x00;
148     pci_conf[0x07] = 0x02; /* PCI_status_devsel_medium */
149     pci_conf[0x4c] = 0x4d;
150     pci_conf[0x4e] = 0x03;
151     pci_conf[0x4f] = 0x00;
152     pci_conf[0x60] = 0x80;
153     pci_conf[0x61] = 0x80;
154     pci_conf[0x62] = 0x80;
155     pci_conf[0x63] = 0x80;
156     pci_conf[0x69] = 0x02;
157     pci_conf[0x70] = 0x80;
158     pci_conf[0x76] = 0x0c;
159     pci_conf[0x77] = 0x0c;
160     pci_conf[0x78] = 0x02;
161     pci_conf[0x79] = 0x00;
162     pci_conf[0x80] = 0x00;
163     pci_conf[0x82] = 0x00;
164     pci_conf[0xa0] = 0x08;
165     pci_conf[0xa2] = 0x00;
166     pci_conf[0xa3] = 0x00;
167     pci_conf[0xa4] = 0x00;
168     pci_conf[0xa5] = 0x00;
169     pci_conf[0xa6] = 0x00;
170     pci_conf[0xa7] = 0x00;
171     pci_conf[0xa8] = 0x0f;
172     pci_conf[0xaa] = 0x00;
173     pci_conf[0xab] = 0x00;
174     pci_conf[0xac] = 0x00;
175     pci_conf[0xae] = 0x00;
176 
177     d->pic_levels = 0;
178     d->rcr = 0;
179 }
180 
181 static int piix3_post_load(void *opaque, int version_id)
182 {
183     PIIX3State *piix3 = opaque;
184     int pirq;
185 
186     /*
187      * Because the i8259 has not been deserialized yet, qemu_irq_raise
188      * might bring the system to a different state than the saved one;
189      * for example, the interrupt could be masked but the i8259 would
190      * not know that yet and would trigger an interrupt in the CPU.
191      *
192      * Here, we update irq levels without raising the interrupt.
193      * Interrupt state will be deserialized separately through the i8259.
194      */
195     piix3->pic_levels = 0;
196     for (pirq = 0; pirq < PIIX_NUM_PIRQS; pirq++) {
197         piix3_set_irq_level_internal(piix3, pirq,
198             pci_bus_get_irq_level(pci_get_bus(&piix3->dev), pirq));
199     }
200     return 0;
201 }
202 
203 static int piix3_pre_save(void *opaque)
204 {
205     int i;
206     PIIX3State *piix3 = opaque;
207 
208     for (i = 0; i < ARRAY_SIZE(piix3->pci_irq_levels_vmstate); i++) {
209         piix3->pci_irq_levels_vmstate[i] =
210             pci_bus_get_irq_level(pci_get_bus(&piix3->dev), i);
211     }
212 
213     return 0;
214 }
215 
216 static bool piix3_rcr_needed(void *opaque)
217 {
218     PIIX3State *piix3 = opaque;
219 
220     return (piix3->rcr != 0);
221 }
222 
223 static const VMStateDescription vmstate_piix3_rcr = {
224     .name = "PIIX3/rcr",
225     .version_id = 1,
226     .minimum_version_id = 1,
227     .needed = piix3_rcr_needed,
228     .fields = (VMStateField[]) {
229         VMSTATE_UINT8(rcr, PIIX3State),
230         VMSTATE_END_OF_LIST()
231     }
232 };
233 
234 static const VMStateDescription vmstate_piix3 = {
235     .name = "PIIX3",
236     .version_id = 3,
237     .minimum_version_id = 2,
238     .post_load = piix3_post_load,
239     .pre_save = piix3_pre_save,
240     .fields = (VMStateField[]) {
241         VMSTATE_PCI_DEVICE(dev, PIIX3State),
242         VMSTATE_INT32_ARRAY_V(pci_irq_levels_vmstate, PIIX3State,
243                               PIIX_NUM_PIRQS, 3),
244         VMSTATE_END_OF_LIST()
245     },
246     .subsections = (const VMStateDescription*[]) {
247         &vmstate_piix3_rcr,
248         NULL
249     }
250 };
251 
252 
253 static void rcr_write(void *opaque, hwaddr addr, uint64_t val, unsigned len)
254 {
255     PIIX3State *d = opaque;
256 
257     if (val & 4) {
258         qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
259         return;
260     }
261     d->rcr = val & 2; /* keep System Reset type only */
262 }
263 
264 static uint64_t rcr_read(void *opaque, hwaddr addr, unsigned len)
265 {
266     PIIX3State *d = opaque;
267 
268     return d->rcr;
269 }
270 
271 static const MemoryRegionOps rcr_ops = {
272     .read = rcr_read,
273     .write = rcr_write,
274     .endianness = DEVICE_LITTLE_ENDIAN
275 };
276 
277 static void piix3_realize(PCIDevice *dev, Error **errp)
278 {
279     PIIX3State *d = PIIX3_PCI_DEVICE(dev);
280 
281     if (!isa_bus_new(DEVICE(d), get_system_memory(),
282                      pci_address_space_io(dev), errp)) {
283         return;
284     }
285 
286     memory_region_init_io(&d->rcr_mem, OBJECT(dev), &rcr_ops, d,
287                           "piix3-reset-control", 1);
288     memory_region_add_subregion_overlap(pci_address_space_io(dev),
289                                         PIIX_RCR_IOPORT, &d->rcr_mem, 1);
290 
291     qemu_register_reset(piix3_reset, d);
292 }
293 
294 static void pci_piix3_class_init(ObjectClass *klass, void *data)
295 {
296     DeviceClass *dc = DEVICE_CLASS(klass);
297     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
298 
299     dc->desc        = "ISA bridge";
300     dc->vmsd        = &vmstate_piix3;
301     dc->hotpluggable   = false;
302     k->realize      = piix3_realize;
303     k->vendor_id    = PCI_VENDOR_ID_INTEL;
304     /* 82371SB PIIX3 PCI-to-ISA bridge (Step A1) */
305     k->device_id    = PCI_DEVICE_ID_INTEL_82371SB_0;
306     k->class_id     = PCI_CLASS_BRIDGE_ISA;
307     /*
308      * Reason: part of PIIX3 southbridge, needs to be wired up by
309      * pc_piix.c's pc_init1()
310      */
311     dc->user_creatable = false;
312 }
313 
314 static const TypeInfo piix3_pci_type_info = {
315     .name = TYPE_PIIX3_PCI_DEVICE,
316     .parent = TYPE_PCI_DEVICE,
317     .instance_size = sizeof(PIIX3State),
318     .abstract = true,
319     .class_init = pci_piix3_class_init,
320     .interfaces = (InterfaceInfo[]) {
321         { INTERFACE_CONVENTIONAL_PCI_DEVICE },
322         { },
323     },
324 };
325 
326 static void piix3_class_init(ObjectClass *klass, void *data)
327 {
328     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
329 
330     k->config_write = piix3_write_config;
331 }
332 
333 static const TypeInfo piix3_info = {
334     .name          = TYPE_PIIX3_DEVICE,
335     .parent        = TYPE_PIIX3_PCI_DEVICE,
336     .class_init    = piix3_class_init,
337 };
338 
339 static void piix3_xen_class_init(ObjectClass *klass, void *data)
340 {
341     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
342 
343     k->config_write = piix3_write_config_xen;
344 };
345 
346 static const TypeInfo piix3_xen_info = {
347     .name          = TYPE_PIIX3_XEN_DEVICE,
348     .parent        = TYPE_PIIX3_PCI_DEVICE,
349     .class_init    = piix3_xen_class_init,
350 };
351 
352 static void piix3_register_types(void)
353 {
354     type_register_static(&piix3_pci_type_info);
355     type_register_static(&piix3_info);
356     type_register_static(&piix3_xen_info);
357 }
358 
359 type_init(piix3_register_types)
360 
361 /*
362  * Return the global irq number corresponding to a given device irq
363  * pin. We could also use the bus number to have a more precise mapping.
364  */
365 static int pci_slot_get_pirq(PCIDevice *pci_dev, int pci_intx)
366 {
367     int slot_addend;
368     slot_addend = (pci_dev->devfn >> 3) - 1;
369     return (pci_intx + slot_addend) & 3;
370 }
371 
372 PIIX3State *piix3_create(PCIBus *pci_bus, ISABus **isa_bus)
373 {
374     PIIX3State *piix3;
375     PCIDevice *pci_dev;
376 
377     /*
378      * Xen supports additional interrupt routes from the PCI devices to
379      * the IOAPIC: the four pins of each PCI device on the bus are also
380      * connected to the IOAPIC directly.
381      * These additional routes can be discovered through ACPI.
382      */
383     if (xen_enabled()) {
384         pci_dev = pci_create_simple_multifunction(pci_bus, -1, true,
385                                                   TYPE_PIIX3_XEN_DEVICE);
386         piix3 = PIIX3_PCI_DEVICE(pci_dev);
387         pci_bus_irqs(pci_bus, xen_piix3_set_irq, xen_pci_slot_get_pirq,
388                      piix3, XEN_PIIX_NUM_PIRQS);
389     } else {
390         pci_dev = pci_create_simple_multifunction(pci_bus, -1, true,
391                                                   TYPE_PIIX3_DEVICE);
392         piix3 = PIIX3_PCI_DEVICE(pci_dev);
393         pci_bus_irqs(pci_bus, piix3_set_irq, pci_slot_get_pirq,
394                      piix3, PIIX_NUM_PIRQS);
395         pci_bus_set_route_irq_fn(pci_bus, piix3_route_intx_pin_to_irq);
396     }
397     *isa_bus = ISA_BUS(qdev_get_child_bus(DEVICE(piix3), "isa.0"));
398 
399     return piix3;
400 }
401