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