1 /*
2 * ARM Versatile/PB PCI host controller
3 *
4 * Copyright (c) 2006-2009 CodeSourcery.
5 * Written by Paul Brook
6 *
7 * This code is licensed under the LGPL.
8 */
9
10 #include "qemu/osdep.h"
11 #include "qemu/units.h"
12 #include "hw/sysbus.h"
13 #include "migration/vmstate.h"
14 #include "hw/irq.h"
15 #include "hw/pci/pci_device.h"
16 #include "hw/pci/pci_bus.h"
17 #include "hw/pci/pci_host.h"
18 #include "hw/qdev-properties.h"
19 #include "qemu/log.h"
20 #include "qemu/module.h"
21 #include "qom/object.h"
22
23 /* Old and buggy versions of QEMU used the wrong mapping from
24 * PCI IRQs to system interrupt lines. Unfortunately the Linux
25 * kernel also had the corresponding bug in setting up interrupts
26 * (so older kernels work on QEMU and not on real hardware).
27 * We automatically detect these broken kernels and flip back
28 * to the broken irq mapping by spotting guest writes to the
29 * PCI_INTERRUPT_LINE register to see where the guest thinks
30 * interrupts are going to be routed. So we start in state
31 * ASSUME_OK on reset, and transition to either BROKEN or
32 * FORCE_OK at the first write to an INTERRUPT_LINE register for
33 * a slot where broken and correct interrupt mapping would differ.
34 * Once in either BROKEN or FORCE_OK we never transition again;
35 * this allows a newer kernel to use the INTERRUPT_LINE
36 * registers arbitrarily once it has indicated that it isn't
37 * broken in its init code somewhere.
38 *
39 * Unfortunately we have to cope with multiple different
40 * variants on the broken kernel behaviour:
41 * phase I (before kernel commit 1bc39ac5d) kernels assume old
42 * QEMU behaviour, so they use IRQ 27 for all slots
43 * phase II (1bc39ac5d and later, but before e3e92a7be6) kernels
44 * swizzle IRQs between slots, but do it wrongly, so they
45 * work only for every fourth PCI card, and only if (like old
46 * QEMU) the PCI host device is at slot 0 rather than where
47 * the h/w actually puts it
48 * phase III (e3e92a7be6 and later) kernels still swizzle IRQs between
49 * slots wrongly, but add a fixed offset of 64 to everything
50 * they write to PCI_INTERRUPT_LINE.
51 *
52 * We live in hope of a mythical phase IV kernel which might
53 * actually behave in ways that work on the hardware. Such a
54 * kernel should probably start off by writing some value neither
55 * 27 nor 91 to slot zero's PCI_INTERRUPT_LINE register to
56 * disable the autodetection. After that it can do what it likes.
57 *
58 * Slot % 4 | hw | I | II | III
59 * -------------------------------
60 * 0 | 29 | 27 | 27 | 91
61 * 1 | 30 | 27 | 28 | 92
62 * 2 | 27 | 27 | 29 | 93
63 * 3 | 28 | 27 | 30 | 94
64 *
65 * Since our autodetection is not perfect we also provide a
66 * property so the user can make us start in BROKEN or FORCE_OK
67 * on reset if they know they have a bad or good kernel.
68 */
69 enum {
70 PCI_VPB_IRQMAP_ASSUME_OK,
71 PCI_VPB_IRQMAP_BROKEN,
72 PCI_VPB_IRQMAP_FORCE_OK,
73 };
74
75 struct PCIVPBState {
76 PCIHostState parent_obj;
77
78 qemu_irq irq[4];
79 MemoryRegion controlregs;
80 MemoryRegion mem_config;
81 MemoryRegion mem_config2;
82 /* Containers representing the PCI address spaces */
83 MemoryRegion pci_io_space;
84 MemoryRegion pci_mem_space;
85 /* Alias regions into PCI address spaces which we expose as sysbus regions.
86 * The offsets into pci_mem_space are controlled by the imap registers.
87 */
88 MemoryRegion pci_io_window;
89 MemoryRegion pci_mem_window[3];
90 PCIBus pci_bus;
91 PCIDevice pci_dev;
92
93 /* Constant for life of device: */
94 int realview;
95 uint32_t mem_win_size[3];
96 uint8_t irq_mapping_prop;
97
98 /* Variable state: */
99 uint32_t imap[3];
100 uint32_t smap[3];
101 uint32_t selfid;
102 uint32_t flags;
103 uint8_t irq_mapping;
104 };
105 typedef struct PCIVPBState PCIVPBState;
106
pci_vpb_update_window(PCIVPBState * s,int i)107 static void pci_vpb_update_window(PCIVPBState *s, int i)
108 {
109 /* Adjust the offset of the alias region we use for
110 * the memory window i to account for a change in the
111 * value of the corresponding IMAP register.
112 * Note that the semantics of the IMAP register differ
113 * for realview and versatile variants of the controller.
114 */
115 hwaddr offset;
116 if (s->realview) {
117 /* Top bits of register (masked according to window size) provide
118 * top bits of PCI address.
119 */
120 offset = s->imap[i] & ~(s->mem_win_size[i] - 1);
121 } else {
122 /* Bottom 4 bits of register provide top 4 bits of PCI address */
123 offset = s->imap[i] << 28;
124 }
125 memory_region_set_alias_offset(&s->pci_mem_window[i], offset);
126 }
127
pci_vpb_update_all_windows(PCIVPBState * s)128 static void pci_vpb_update_all_windows(PCIVPBState *s)
129 {
130 /* Update all alias windows based on the current register state */
131 int i;
132
133 for (i = 0; i < 3; i++) {
134 pci_vpb_update_window(s, i);
135 }
136 }
137
pci_vpb_post_load(void * opaque,int version_id)138 static int pci_vpb_post_load(void *opaque, int version_id)
139 {
140 PCIVPBState *s = opaque;
141 pci_vpb_update_all_windows(s);
142 return 0;
143 }
144
145 static const VMStateDescription pci_vpb_vmstate = {
146 .name = "versatile-pci",
147 .version_id = 1,
148 .minimum_version_id = 1,
149 .post_load = pci_vpb_post_load,
150 .fields = (const VMStateField[]) {
151 VMSTATE_UINT32_ARRAY(imap, PCIVPBState, 3),
152 VMSTATE_UINT32_ARRAY(smap, PCIVPBState, 3),
153 VMSTATE_UINT32(selfid, PCIVPBState),
154 VMSTATE_UINT32(flags, PCIVPBState),
155 VMSTATE_UINT8(irq_mapping, PCIVPBState),
156 VMSTATE_END_OF_LIST()
157 }
158 };
159
160 #define TYPE_VERSATILE_PCI "versatile_pci"
161 DECLARE_INSTANCE_CHECKER(PCIVPBState, PCI_VPB,
162 TYPE_VERSATILE_PCI)
163
164 #define TYPE_VERSATILE_PCI_HOST "versatile_pci_host"
165 DECLARE_INSTANCE_CHECKER(PCIDevice, PCI_VPB_HOST,
166 TYPE_VERSATILE_PCI_HOST)
167
168 typedef enum {
169 PCI_IMAP0 = 0x0,
170 PCI_IMAP1 = 0x4,
171 PCI_IMAP2 = 0x8,
172 PCI_SELFID = 0xc,
173 PCI_FLAGS = 0x10,
174 PCI_SMAP0 = 0x14,
175 PCI_SMAP1 = 0x18,
176 PCI_SMAP2 = 0x1c,
177 } PCIVPBControlRegs;
178
pci_vpb_reg_write(void * opaque,hwaddr addr,uint64_t val,unsigned size)179 static void pci_vpb_reg_write(void *opaque, hwaddr addr,
180 uint64_t val, unsigned size)
181 {
182 PCIVPBState *s = opaque;
183
184 switch (addr) {
185 case PCI_IMAP0:
186 case PCI_IMAP1:
187 case PCI_IMAP2:
188 {
189 int win = (addr - PCI_IMAP0) >> 2;
190 s->imap[win] = val;
191 pci_vpb_update_window(s, win);
192 break;
193 }
194 case PCI_SELFID:
195 s->selfid = val;
196 break;
197 case PCI_FLAGS:
198 s->flags = val;
199 break;
200 case PCI_SMAP0:
201 case PCI_SMAP1:
202 case PCI_SMAP2:
203 {
204 int win = (addr - PCI_SMAP0) >> 2;
205 s->smap[win] = val;
206 break;
207 }
208 default:
209 qemu_log_mask(LOG_GUEST_ERROR,
210 "pci_vpb_reg_write: Bad offset %x\n", (int)addr);
211 break;
212 }
213 }
214
pci_vpb_reg_read(void * opaque,hwaddr addr,unsigned size)215 static uint64_t pci_vpb_reg_read(void *opaque, hwaddr addr,
216 unsigned size)
217 {
218 PCIVPBState *s = opaque;
219
220 switch (addr) {
221 case PCI_IMAP0:
222 case PCI_IMAP1:
223 case PCI_IMAP2:
224 {
225 int win = (addr - PCI_IMAP0) >> 2;
226 return s->imap[win];
227 }
228 case PCI_SELFID:
229 return s->selfid;
230 case PCI_FLAGS:
231 return s->flags;
232 case PCI_SMAP0:
233 case PCI_SMAP1:
234 case PCI_SMAP2:
235 {
236 int win = (addr - PCI_SMAP0) >> 2;
237 return s->smap[win];
238 }
239 default:
240 qemu_log_mask(LOG_GUEST_ERROR,
241 "pci_vpb_reg_read: Bad offset %x\n", (int)addr);
242 return 0;
243 }
244 }
245
246 static const MemoryRegionOps pci_vpb_reg_ops = {
247 .read = pci_vpb_reg_read,
248 .write = pci_vpb_reg_write,
249 .endianness = DEVICE_NATIVE_ENDIAN,
250 .valid = {
251 .min_access_size = 4,
252 .max_access_size = 4,
253 },
254 };
255
pci_vpb_broken_irq(int slot,int irq)256 static int pci_vpb_broken_irq(int slot, int irq)
257 {
258 /* Determine whether this IRQ value for this slot represents a
259 * known broken Linux kernel behaviour for this slot.
260 * Return one of the PCI_VPB_IRQMAP_ constants:
261 * BROKEN : if this definitely looks like a broken kernel
262 * FORCE_OK : if this definitely looks good
263 * ASSUME_OK : if we can't tell
264 */
265 slot %= PCI_NUM_PINS;
266
267 if (irq == 27) {
268 if (slot == 2) {
269 /* Might be a Phase I kernel, or might be a fixed kernel,
270 * since slot 2 is where we expect this IRQ.
271 */
272 return PCI_VPB_IRQMAP_ASSUME_OK;
273 }
274 /* Phase I kernel */
275 return PCI_VPB_IRQMAP_BROKEN;
276 }
277 if (irq == slot + 27) {
278 /* Phase II kernel */
279 return PCI_VPB_IRQMAP_BROKEN;
280 }
281 if (irq == slot + 27 + 64) {
282 /* Phase III kernel */
283 return PCI_VPB_IRQMAP_BROKEN;
284 }
285 /* Anything else must be a fixed kernel, possibly using an
286 * arbitrary irq map.
287 */
288 return PCI_VPB_IRQMAP_FORCE_OK;
289 }
290
pci_vpb_config_write(void * opaque,hwaddr addr,uint64_t val,unsigned size)291 static void pci_vpb_config_write(void *opaque, hwaddr addr,
292 uint64_t val, unsigned size)
293 {
294 PCIVPBState *s = opaque;
295 if (!s->realview && (addr & 0xff) == PCI_INTERRUPT_LINE
296 && s->irq_mapping == PCI_VPB_IRQMAP_ASSUME_OK) {
297 uint8_t devfn = addr >> 8;
298 s->irq_mapping = pci_vpb_broken_irq(PCI_SLOT(devfn), val);
299 }
300 pci_data_write(&s->pci_bus, addr, val, size);
301 }
302
pci_vpb_config_read(void * opaque,hwaddr addr,unsigned size)303 static uint64_t pci_vpb_config_read(void *opaque, hwaddr addr,
304 unsigned size)
305 {
306 PCIVPBState *s = opaque;
307 uint32_t val;
308 val = pci_data_read(&s->pci_bus, addr, size);
309 return val;
310 }
311
312 static const MemoryRegionOps pci_vpb_config_ops = {
313 .read = pci_vpb_config_read,
314 .write = pci_vpb_config_write,
315 .endianness = DEVICE_NATIVE_ENDIAN,
316 };
317
pci_vpb_map_irq(PCIDevice * d,int irq_num)318 static int pci_vpb_map_irq(PCIDevice *d, int irq_num)
319 {
320 PCIVPBState *s = container_of(pci_get_bus(d), PCIVPBState, pci_bus);
321
322 if (s->irq_mapping == PCI_VPB_IRQMAP_BROKEN) {
323 /* Legacy broken IRQ mapping for compatibility with old and
324 * buggy Linux guests
325 */
326 return irq_num;
327 }
328
329 /* Slot to IRQ mapping for RealView Platform Baseboard 926 backplane
330 * name slot IntA IntB IntC IntD
331 * A 31 IRQ28 IRQ29 IRQ30 IRQ27
332 * B 30 IRQ27 IRQ28 IRQ29 IRQ30
333 * C 29 IRQ30 IRQ27 IRQ28 IRQ29
334 * Slot C is for the host bridge; A and B the peripherals.
335 * Our output irqs 0..3 correspond to the baseboard's 27..30.
336 *
337 * This mapping function takes account of an oddity in the PB926
338 * board wiring, where the FPGA's P_nINTA input is connected to
339 * the INTB connection on the board PCI edge connector, P_nINTB
340 * is connected to INTC, and so on, so everything is one number
341 * further round from where you might expect.
342 */
343 return pci_swizzle_map_irq_fn(d, irq_num + 2);
344 }
345
pci_vpb_rv_map_irq(PCIDevice * d,int irq_num)346 static int pci_vpb_rv_map_irq(PCIDevice *d, int irq_num)
347 {
348 /* Slot to IRQ mapping for RealView EB and PB1176 backplane
349 * name slot IntA IntB IntC IntD
350 * A 31 IRQ50 IRQ51 IRQ48 IRQ49
351 * B 30 IRQ49 IRQ50 IRQ51 IRQ48
352 * C 29 IRQ48 IRQ49 IRQ50 IRQ51
353 * Slot C is for the host bridge; A and B the peripherals.
354 * Our output irqs 0..3 correspond to the baseboard's 48..51.
355 *
356 * The PB1176 and EB boards don't have the PB926 wiring oddity
357 * described above; P_nINTA connects to INTA, P_nINTB to INTB
358 * and so on, which is why this mapping function is different.
359 */
360 return pci_swizzle_map_irq_fn(d, irq_num + 3);
361 }
362
pci_vpb_set_irq(void * opaque,int irq_num,int level)363 static void pci_vpb_set_irq(void *opaque, int irq_num, int level)
364 {
365 qemu_irq *pic = opaque;
366
367 qemu_set_irq(pic[irq_num], level);
368 }
369
pci_vpb_reset(DeviceState * d)370 static void pci_vpb_reset(DeviceState *d)
371 {
372 PCIVPBState *s = PCI_VPB(d);
373
374 s->imap[0] = 0;
375 s->imap[1] = 0;
376 s->imap[2] = 0;
377 s->smap[0] = 0;
378 s->smap[1] = 0;
379 s->smap[2] = 0;
380 s->selfid = 0;
381 s->flags = 0;
382 s->irq_mapping = s->irq_mapping_prop;
383
384 pci_vpb_update_all_windows(s);
385 }
386
pci_vpb_init(Object * obj)387 static void pci_vpb_init(Object *obj)
388 {
389 PCIVPBState *s = PCI_VPB(obj);
390
391 /* Window sizes for VersatilePB; realview_pci's init will override */
392 s->mem_win_size[0] = 0x0c000000;
393 s->mem_win_size[1] = 0x10000000;
394 s->mem_win_size[2] = 0x10000000;
395 }
396
pci_vpb_realize(DeviceState * dev,Error ** errp)397 static void pci_vpb_realize(DeviceState *dev, Error **errp)
398 {
399 PCIVPBState *s = PCI_VPB(dev);
400 PCIHostState *h = PCI_HOST_BRIDGE(dev);
401 SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
402 pci_map_irq_fn mapfn;
403 int i;
404
405 memory_region_init(&s->pci_io_space, OBJECT(s), "pci_io", 4 * GiB);
406 memory_region_init(&s->pci_mem_space, OBJECT(s), "pci_mem", 4 * GiB);
407
408 pci_root_bus_init(&s->pci_bus, sizeof(s->pci_bus), dev, "pci",
409 &s->pci_mem_space, &s->pci_io_space,
410 PCI_DEVFN(11, 0), TYPE_PCI_BUS);
411 h->bus = &s->pci_bus;
412
413 object_initialize(&s->pci_dev, sizeof(s->pci_dev), TYPE_VERSATILE_PCI_HOST);
414
415 for (i = 0; i < 4; i++) {
416 sysbus_init_irq(sbd, &s->irq[i]);
417 }
418
419 if (s->realview) {
420 mapfn = pci_vpb_rv_map_irq;
421 } else {
422 mapfn = pci_vpb_map_irq;
423 }
424
425 pci_bus_irqs(&s->pci_bus, pci_vpb_set_irq, s->irq, 4);
426 pci_bus_map_irqs(&s->pci_bus, mapfn);
427
428 /* Our memory regions are:
429 * 0 : our control registers
430 * 1 : PCI self config window
431 * 2 : PCI config window
432 * 3 : PCI IO window
433 * 4..6 : PCI memory windows
434 */
435 memory_region_init_io(&s->controlregs, OBJECT(s), &pci_vpb_reg_ops, s,
436 "pci-vpb-regs", 0x1000);
437 sysbus_init_mmio(sbd, &s->controlregs);
438 memory_region_init_io(&s->mem_config, OBJECT(s), &pci_vpb_config_ops, s,
439 "pci-vpb-selfconfig", 0x1000000);
440 sysbus_init_mmio(sbd, &s->mem_config);
441 memory_region_init_io(&s->mem_config2, OBJECT(s), &pci_vpb_config_ops, s,
442 "pci-vpb-config", 0x1000000);
443 sysbus_init_mmio(sbd, &s->mem_config2);
444
445 /* The window into I/O space is always into a fixed base address;
446 * its size is the same for both realview and versatile.
447 */
448 memory_region_init_alias(&s->pci_io_window, OBJECT(s), "pci-vbp-io-window",
449 &s->pci_io_space, 0, 0x100000);
450
451 sysbus_init_mmio(sbd, &s->pci_io_space);
452
453 /* Create the alias regions corresponding to our three windows onto
454 * PCI memory space. The sizes vary from board to board; the base
455 * offsets are guest controllable via the IMAP registers.
456 */
457 for (i = 0; i < 3; i++) {
458 memory_region_init_alias(&s->pci_mem_window[i], OBJECT(s), "pci-vbp-window",
459 &s->pci_mem_space, 0, s->mem_win_size[i]);
460 sysbus_init_mmio(sbd, &s->pci_mem_window[i]);
461 }
462
463 /* TODO Remove once realize propagates to child devices. */
464 qdev_realize(DEVICE(&s->pci_dev), BUS(&s->pci_bus), errp);
465 }
466
versatile_pci_host_realize(PCIDevice * d,Error ** errp)467 static void versatile_pci_host_realize(PCIDevice *d, Error **errp)
468 {
469 pci_set_word(d->config + PCI_STATUS,
470 PCI_STATUS_66MHZ | PCI_STATUS_DEVSEL_MEDIUM);
471 pci_set_byte(d->config + PCI_LATENCY_TIMER, 0x10);
472 }
473
versatile_pci_host_class_init(ObjectClass * klass,void * data)474 static void versatile_pci_host_class_init(ObjectClass *klass, void *data)
475 {
476 PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
477 DeviceClass *dc = DEVICE_CLASS(klass);
478
479 k->realize = versatile_pci_host_realize;
480 k->vendor_id = PCI_VENDOR_ID_XILINX;
481 k->device_id = PCI_DEVICE_ID_XILINX_XC2VP30;
482 k->class_id = PCI_CLASS_PROCESSOR_CO;
483 /*
484 * PCI-facing part of the host bridge, not usable without the
485 * host-facing part, which can't be device_add'ed, yet.
486 */
487 dc->user_creatable = false;
488 }
489
490 static const TypeInfo versatile_pci_host_info = {
491 .name = TYPE_VERSATILE_PCI_HOST,
492 .parent = TYPE_PCI_DEVICE,
493 .instance_size = sizeof(PCIDevice),
494 .class_init = versatile_pci_host_class_init,
495 .interfaces = (InterfaceInfo[]) {
496 { INTERFACE_CONVENTIONAL_PCI_DEVICE },
497 { },
498 },
499 };
500
501 static Property pci_vpb_properties[] = {
502 DEFINE_PROP_UINT8("broken-irq-mapping", PCIVPBState, irq_mapping_prop,
503 PCI_VPB_IRQMAP_ASSUME_OK),
504 DEFINE_PROP_END_OF_LIST()
505 };
506
pci_vpb_class_init(ObjectClass * klass,void * data)507 static void pci_vpb_class_init(ObjectClass *klass, void *data)
508 {
509 DeviceClass *dc = DEVICE_CLASS(klass);
510
511 dc->realize = pci_vpb_realize;
512 dc->reset = pci_vpb_reset;
513 dc->vmsd = &pci_vpb_vmstate;
514 device_class_set_props(dc, pci_vpb_properties);
515 }
516
517 static const TypeInfo pci_vpb_info = {
518 .name = TYPE_VERSATILE_PCI,
519 .parent = TYPE_PCI_HOST_BRIDGE,
520 .instance_size = sizeof(PCIVPBState),
521 .instance_init = pci_vpb_init,
522 .class_init = pci_vpb_class_init,
523 };
524
pci_realview_init(Object * obj)525 static void pci_realview_init(Object *obj)
526 {
527 PCIVPBState *s = PCI_VPB(obj);
528
529 s->realview = 1;
530 /* The PCI window sizes are different on Realview boards */
531 s->mem_win_size[0] = 0x01000000;
532 s->mem_win_size[1] = 0x04000000;
533 s->mem_win_size[2] = 0x08000000;
534 }
535
536 static const TypeInfo pci_realview_info = {
537 .name = "realview_pci",
538 .parent = TYPE_VERSATILE_PCI,
539 .instance_init = pci_realview_init,
540 };
541
versatile_pci_register_types(void)542 static void versatile_pci_register_types(void)
543 {
544 type_register_static(&pci_vpb_info);
545 type_register_static(&pci_realview_info);
546 type_register_static(&versatile_pci_host_info);
547 }
548
549 type_init(versatile_pci_register_types)
550