xref: /linux/arch/mips/pci/pci-xtalk-bridge.c (revision e53524cdcc02d089e757b668da031ba06ff665c3)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2003 Christoph Hellwig (hch@lst.de)
4  * Copyright (C) 1999, 2000, 04 Ralf Baechle (ralf@linux-mips.org)
5  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
6  */
7 #include <linux/kernel.h>
8 #include <linux/export.h>
9 #include <linux/pci.h>
10 #include <linux/smp.h>
11 #include <linux/dma-direct.h>
12 #include <linux/platform_device.h>
13 #include <linux/platform_data/xtalk-bridge.h>
14 #include <linux/nvmem-consumer.h>
15 #include <linux/crc16.h>
16 #include <linux/irqdomain.h>
17 
18 #include <asm/pci/bridge.h>
19 #include <asm/paccess.h>
20 #include <asm/sn/irq_alloc.h>
21 #include <asm/sn/ioc3.h>
22 
23 #define CRC16_INIT	0
24 #define CRC16_VALID	0xb001
25 
26 /*
27  * Common phys<->dma mapping for platforms using pci xtalk bridge
28  */
29 dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
30 {
31 	struct pci_dev *pdev = to_pci_dev(dev);
32 	struct bridge_controller *bc = BRIDGE_CONTROLLER(pdev->bus);
33 
34 	return bc->baddr + paddr;
35 }
36 
37 phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dma_addr)
38 {
39 	return dma_addr & ~(0xffUL << 56);
40 }
41 
42 /*
43  * Most of the IOC3 PCI config register aren't present
44  * we emulate what is needed for a normal PCI enumeration
45  */
46 static int ioc3_cfg_rd(void *addr, int where, int size, u32 *value, u32 sid)
47 {
48 	u32 cf, shift, mask;
49 
50 	switch (where & ~3) {
51 	case 0x00 ... 0x10:
52 	case 0x40 ... 0x44:
53 		if (get_dbe(cf, (u32 *)addr))
54 			return PCIBIOS_DEVICE_NOT_FOUND;
55 		break;
56 	case 0x2c:
57 		cf = sid;
58 		break;
59 	case 0x3c:
60 		/* emulate sane interrupt pin value */
61 		cf = 0x00000100;
62 		break;
63 	default:
64 		cf = 0;
65 		break;
66 	}
67 	shift = (where & 3) << 3;
68 	mask = 0xffffffffU >> ((4 - size) << 3);
69 	*value = (cf >> shift) & mask;
70 
71 	return PCIBIOS_SUCCESSFUL;
72 }
73 
74 static int ioc3_cfg_wr(void *addr, int where, int size, u32 value)
75 {
76 	u32 cf, shift, mask, smask;
77 
78 	if ((where >= 0x14 && where < 0x40) || (where >= 0x48))
79 		return PCIBIOS_SUCCESSFUL;
80 
81 	if (get_dbe(cf, (u32 *)addr))
82 		return PCIBIOS_DEVICE_NOT_FOUND;
83 
84 	shift = ((where & 3) << 3);
85 	mask = (0xffffffffU >> ((4 - size) << 3));
86 	smask = mask << shift;
87 
88 	cf = (cf & ~smask) | ((value & mask) << shift);
89 	if (put_dbe(cf, (u32 *)addr))
90 		return PCIBIOS_DEVICE_NOT_FOUND;
91 
92 	return PCIBIOS_SUCCESSFUL;
93 }
94 
95 static void bridge_disable_swapping(struct pci_dev *dev)
96 {
97 	struct bridge_controller *bc = BRIDGE_CONTROLLER(dev->bus);
98 	int slot = PCI_SLOT(dev->devfn);
99 
100 	/* Turn off byte swapping */
101 	bridge_clr(bc, b_device[slot].reg, BRIDGE_DEV_SWAP_DIR);
102 	bridge_read(bc, b_widget.w_tflush);	/* Flush */
103 }
104 
105 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_SGI, PCI_DEVICE_ID_SGI_IOC3,
106 	bridge_disable_swapping);
107 
108 
109 /*
110  * The Bridge ASIC supports both type 0 and type 1 access.  Type 1 is
111  * not really documented, so right now I can't write code which uses it.
112  * Therefore we use type 0 accesses for now even though they won't work
113  * correctly for PCI-to-PCI bridges.
114  *
115  * The function is complicated by the ultimate brokenness of the IOC3 chip
116  * which is used in SGI systems.  The IOC3 can only handle 32-bit PCI
117  * accesses and does only decode parts of it's address space.
118  */
119 static int pci_conf0_read_config(struct pci_bus *bus, unsigned int devfn,
120 				 int where, int size, u32 *value)
121 {
122 	struct bridge_controller *bc = BRIDGE_CONTROLLER(bus);
123 	struct bridge_regs *bridge = bc->base;
124 	int slot = PCI_SLOT(devfn);
125 	int fn = PCI_FUNC(devfn);
126 	void *addr;
127 	u32 cf;
128 	int res;
129 
130 	addr = &bridge->b_type0_cfg_dev[slot].f[fn].c[PCI_VENDOR_ID];
131 	if (get_dbe(cf, (u32 *)addr))
132 		return PCIBIOS_DEVICE_NOT_FOUND;
133 
134 	/*
135 	 * IOC3 is broken beyond belief ...  Don't even give the
136 	 * generic PCI code a chance to look at it for real ...
137 	 */
138 	if (cf == (PCI_VENDOR_ID_SGI | (PCI_DEVICE_ID_SGI_IOC3 << 16))) {
139 		addr = &bridge->b_type0_cfg_dev[slot].f[fn].l[where >> 2];
140 		return ioc3_cfg_rd(addr, where, size, value,
141 				   bc->ioc3_sid[slot]);
142 	}
143 
144 	addr = &bridge->b_type0_cfg_dev[slot].f[fn].c[where ^ (4 - size)];
145 
146 	if (size == 1)
147 		res = get_dbe(*value, (u8 *)addr);
148 	else if (size == 2)
149 		res = get_dbe(*value, (u16 *)addr);
150 	else
151 		res = get_dbe(*value, (u32 *)addr);
152 
153 	return res ? PCIBIOS_DEVICE_NOT_FOUND : PCIBIOS_SUCCESSFUL;
154 }
155 
156 static int pci_conf1_read_config(struct pci_bus *bus, unsigned int devfn,
157 				 int where, int size, u32 *value)
158 {
159 	struct bridge_controller *bc = BRIDGE_CONTROLLER(bus);
160 	struct bridge_regs *bridge = bc->base;
161 	int busno = bus->number;
162 	int slot = PCI_SLOT(devfn);
163 	int fn = PCI_FUNC(devfn);
164 	void *addr;
165 	u32 cf;
166 	int res;
167 
168 	bridge_write(bc, b_pci_cfg, (busno << 16) | (slot << 11));
169 	addr = &bridge->b_type1_cfg.c[(fn << 8) | PCI_VENDOR_ID];
170 	if (get_dbe(cf, (u32 *)addr))
171 		return PCIBIOS_DEVICE_NOT_FOUND;
172 
173 	/*
174 	 * IOC3 is broken beyond belief ...  Don't even give the
175 	 * generic PCI code a chance to look at it for real ...
176 	 */
177 	if (cf == (PCI_VENDOR_ID_SGI | (PCI_DEVICE_ID_SGI_IOC3 << 16))) {
178 		addr = &bridge->b_type1_cfg.c[(fn << 8) | (where & ~3)];
179 		return ioc3_cfg_rd(addr, where, size, value,
180 				   bc->ioc3_sid[slot]);
181 	}
182 
183 	addr = &bridge->b_type1_cfg.c[(fn << 8) | (where ^ (4 - size))];
184 
185 	if (size == 1)
186 		res = get_dbe(*value, (u8 *)addr);
187 	else if (size == 2)
188 		res = get_dbe(*value, (u16 *)addr);
189 	else
190 		res = get_dbe(*value, (u32 *)addr);
191 
192 	return res ? PCIBIOS_DEVICE_NOT_FOUND : PCIBIOS_SUCCESSFUL;
193 }
194 
195 static int pci_read_config(struct pci_bus *bus, unsigned int devfn,
196 			   int where, int size, u32 *value)
197 {
198 	if (!pci_is_root_bus(bus))
199 		return pci_conf1_read_config(bus, devfn, where, size, value);
200 
201 	return pci_conf0_read_config(bus, devfn, where, size, value);
202 }
203 
204 static int pci_conf0_write_config(struct pci_bus *bus, unsigned int devfn,
205 				  int where, int size, u32 value)
206 {
207 	struct bridge_controller *bc = BRIDGE_CONTROLLER(bus);
208 	struct bridge_regs *bridge = bc->base;
209 	int slot = PCI_SLOT(devfn);
210 	int fn = PCI_FUNC(devfn);
211 	void *addr;
212 	u32 cf;
213 	int res;
214 
215 	addr = &bridge->b_type0_cfg_dev[slot].f[fn].c[PCI_VENDOR_ID];
216 	if (get_dbe(cf, (u32 *)addr))
217 		return PCIBIOS_DEVICE_NOT_FOUND;
218 
219 	/*
220 	 * IOC3 is broken beyond belief ...  Don't even give the
221 	 * generic PCI code a chance to look at it for real ...
222 	 */
223 	if (cf == (PCI_VENDOR_ID_SGI | (PCI_DEVICE_ID_SGI_IOC3 << 16))) {
224 		addr = &bridge->b_type0_cfg_dev[slot].f[fn].l[where >> 2];
225 		return ioc3_cfg_wr(addr, where, size, value);
226 	}
227 
228 	addr = &bridge->b_type0_cfg_dev[slot].f[fn].c[where ^ (4 - size)];
229 
230 	if (size == 1)
231 		res = put_dbe(value, (u8 *)addr);
232 	else if (size == 2)
233 		res = put_dbe(value, (u16 *)addr);
234 	else
235 		res = put_dbe(value, (u32 *)addr);
236 
237 	if (res)
238 		return PCIBIOS_DEVICE_NOT_FOUND;
239 
240 	return PCIBIOS_SUCCESSFUL;
241 }
242 
243 static int pci_conf1_write_config(struct pci_bus *bus, unsigned int devfn,
244 				  int where, int size, u32 value)
245 {
246 	struct bridge_controller *bc = BRIDGE_CONTROLLER(bus);
247 	struct bridge_regs *bridge = bc->base;
248 	int slot = PCI_SLOT(devfn);
249 	int fn = PCI_FUNC(devfn);
250 	int busno = bus->number;
251 	void *addr;
252 	u32 cf;
253 	int res;
254 
255 	bridge_write(bc, b_pci_cfg, (busno << 16) | (slot << 11));
256 	addr = &bridge->b_type1_cfg.c[(fn << 8) | PCI_VENDOR_ID];
257 	if (get_dbe(cf, (u32 *)addr))
258 		return PCIBIOS_DEVICE_NOT_FOUND;
259 
260 	/*
261 	 * IOC3 is broken beyond belief ...  Don't even give the
262 	 * generic PCI code a chance to look at it for real ...
263 	 */
264 	if (cf == (PCI_VENDOR_ID_SGI | (PCI_DEVICE_ID_SGI_IOC3 << 16))) {
265 		addr = &bridge->b_type0_cfg_dev[slot].f[fn].l[where >> 2];
266 		return ioc3_cfg_wr(addr, where, size, value);
267 	}
268 
269 	addr = &bridge->b_type1_cfg.c[(fn << 8) | (where ^ (4 - size))];
270 
271 	if (size == 1)
272 		res = put_dbe(value, (u8 *)addr);
273 	else if (size == 2)
274 		res = put_dbe(value, (u16 *)addr);
275 	else
276 		res = put_dbe(value, (u32 *)addr);
277 
278 	if (res)
279 		return PCIBIOS_DEVICE_NOT_FOUND;
280 
281 	return PCIBIOS_SUCCESSFUL;
282 }
283 
284 static int pci_write_config(struct pci_bus *bus, unsigned int devfn,
285 	int where, int size, u32 value)
286 {
287 	if (!pci_is_root_bus(bus))
288 		return pci_conf1_write_config(bus, devfn, where, size, value);
289 
290 	return pci_conf0_write_config(bus, devfn, where, size, value);
291 }
292 
293 static struct pci_ops bridge_pci_ops = {
294 	.read	 = pci_read_config,
295 	.write	 = pci_write_config,
296 };
297 
298 struct bridge_irq_chip_data {
299 	struct bridge_controller *bc;
300 	nasid_t nasid;
301 };
302 
303 static int bridge_set_affinity(struct irq_data *d, const struct cpumask *mask,
304 			       bool force)
305 {
306 #ifdef CONFIG_NUMA
307 	struct bridge_irq_chip_data *data = d->chip_data;
308 	int bit = d->parent_data->hwirq;
309 	int pin = d->hwirq;
310 	int ret, cpu;
311 
312 	ret = irq_chip_set_affinity_parent(d, mask, force);
313 	if (ret >= 0) {
314 		cpu = cpumask_first_and(mask, cpu_online_mask);
315 		data->nasid = cpu_to_node(cpu);
316 		bridge_write(data->bc, b_int_addr[pin].addr,
317 			     (((data->bc->intr_addr >> 30) & 0x30000) |
318 			      bit | (data->nasid << 8)));
319 		bridge_read(data->bc, b_wid_tflush);
320 	}
321 	return ret;
322 #else
323 	return irq_chip_set_affinity_parent(d, mask, force);
324 #endif
325 }
326 
327 struct irq_chip bridge_irq_chip = {
328 	.name             = "BRIDGE",
329 	.irq_mask         = irq_chip_mask_parent,
330 	.irq_unmask       = irq_chip_unmask_parent,
331 	.irq_set_affinity = bridge_set_affinity
332 };
333 
334 static int bridge_domain_alloc(struct irq_domain *domain, unsigned int virq,
335 			       unsigned int nr_irqs, void *arg)
336 {
337 	struct bridge_irq_chip_data *data;
338 	struct irq_alloc_info *info = arg;
339 	int ret;
340 
341 	if (nr_irqs > 1 || !info)
342 		return -EINVAL;
343 
344 	data = kzalloc(sizeof(*data), GFP_KERNEL);
345 	if (!data)
346 		return -ENOMEM;
347 
348 	ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg);
349 	if (ret >= 0) {
350 		data->bc = info->ctrl;
351 		data->nasid = info->nasid;
352 		irq_domain_set_info(domain, virq, info->pin, &bridge_irq_chip,
353 				    data, handle_level_irq, NULL, NULL);
354 	} else {
355 		kfree(data);
356 	}
357 
358 	return ret;
359 }
360 
361 static void bridge_domain_free(struct irq_domain *domain, unsigned int virq,
362 			       unsigned int nr_irqs)
363 {
364 	struct irq_data *irqd = irq_domain_get_irq_data(domain, virq);
365 
366 	if (nr_irqs)
367 		return;
368 
369 	kfree(irqd->chip_data);
370 	irq_domain_free_irqs_top(domain, virq, nr_irqs);
371 }
372 
373 static int bridge_domain_activate(struct irq_domain *domain,
374 				  struct irq_data *irqd, bool reserve)
375 {
376 	struct bridge_irq_chip_data *data = irqd->chip_data;
377 	struct bridge_controller *bc = data->bc;
378 	int bit = irqd->parent_data->hwirq;
379 	int pin = irqd->hwirq;
380 	u32 device;
381 
382 	bridge_write(bc, b_int_addr[pin].addr,
383 		     (((bc->intr_addr >> 30) & 0x30000) |
384 		      bit | (data->nasid << 8)));
385 	bridge_set(bc, b_int_enable, (1 << pin));
386 	bridge_set(bc, b_int_enable, 0x7ffffe00); /* more stuff in int_enable */
387 
388 	/*
389 	 * Enable sending of an interrupt clear packet to the hub on a high to
390 	 * low transition of the interrupt pin.
391 	 *
392 	 * IRIX sets additional bits in the address which are documented as
393 	 * reserved in the bridge docs.
394 	 */
395 	bridge_set(bc, b_int_mode, (1UL << pin));
396 
397 	/*
398 	 * We assume the bridge to have a 1:1 mapping between devices
399 	 * (slots) and intr pins.
400 	 */
401 	device = bridge_read(bc, b_int_device);
402 	device &= ~(7 << (pin*3));
403 	device |= (pin << (pin*3));
404 	bridge_write(bc, b_int_device, device);
405 
406 	bridge_read(bc, b_wid_tflush);
407 	return 0;
408 }
409 
410 static void bridge_domain_deactivate(struct irq_domain *domain,
411 				     struct irq_data *irqd)
412 {
413 	struct bridge_irq_chip_data *data = irqd->chip_data;
414 
415 	bridge_clr(data->bc, b_int_enable, (1 << irqd->hwirq));
416 	bridge_read(data->bc, b_wid_tflush);
417 }
418 
419 static const struct irq_domain_ops bridge_domain_ops = {
420 	.alloc      = bridge_domain_alloc,
421 	.free       = bridge_domain_free,
422 	.activate   = bridge_domain_activate,
423 	.deactivate = bridge_domain_deactivate
424 };
425 
426 /*
427  * All observed requests have pin == 1. We could have a global here, that
428  * gets incremented and returned every time - unfortunately, pci_map_irq
429  * may be called on the same device over and over, and need to return the
430  * same value. On O2000, pin can be 0 or 1, and PCI slots can be [0..7].
431  *
432  * A given PCI device, in general, should be able to intr any of the cpus
433  * on any one of the hubs connected to its xbow.
434  */
435 static int bridge_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
436 {
437 	struct bridge_controller *bc = BRIDGE_CONTROLLER(dev->bus);
438 	struct irq_alloc_info info;
439 	int irq;
440 
441 	switch (pin) {
442 	case PCI_INTERRUPT_UNKNOWN:
443 	case PCI_INTERRUPT_INTA:
444 	case PCI_INTERRUPT_INTC:
445 		pin = 0;
446 		break;
447 	case PCI_INTERRUPT_INTB:
448 	case PCI_INTERRUPT_INTD:
449 		pin = 1;
450 	}
451 
452 	irq = bc->pci_int[slot][pin];
453 	if (irq == -1) {
454 		info.ctrl = bc;
455 		info.nasid = bc->nasid;
456 		info.pin = bc->int_mapping[slot][pin];
457 
458 		irq = irq_domain_alloc_irqs(bc->domain, 1, bc->nasid, &info);
459 		if (irq < 0)
460 			return irq;
461 
462 		bc->pci_int[slot][pin] = irq;
463 	}
464 	return irq;
465 }
466 
467 #define IOC3_SID(sid)	(PCI_VENDOR_ID_SGI | ((sid) << 16))
468 
469 static void bridge_setup_ip27_baseio6g(struct bridge_controller *bc)
470 {
471 	bc->ioc3_sid[2] = IOC3_SID(IOC3_SUBSYS_IP27_BASEIO6G);
472 	bc->ioc3_sid[6] = IOC3_SID(IOC3_SUBSYS_IP27_MIO);
473 	bc->int_mapping[2][1] = 4;
474 	bc->int_mapping[6][1] = 6;
475 }
476 
477 static void bridge_setup_ip27_baseio(struct bridge_controller *bc)
478 {
479 	bc->ioc3_sid[2] = IOC3_SID(IOC3_SUBSYS_IP27_BASEIO);
480 	bc->int_mapping[2][1] = 4;
481 }
482 
483 static void bridge_setup_ip29_baseio(struct bridge_controller *bc)
484 {
485 	bc->ioc3_sid[2] = IOC3_SID(IOC3_SUBSYS_IP29_SYSBOARD);
486 	bc->int_mapping[2][1] = 3;
487 }
488 
489 static void bridge_setup_ip30_sysboard(struct bridge_controller *bc)
490 {
491 	bc->ioc3_sid[2] = IOC3_SID(IOC3_SUBSYS_IP30_SYSBOARD);
492 	bc->int_mapping[2][1] = 4;
493 }
494 
495 static void bridge_setup_menet(struct bridge_controller *bc)
496 {
497 	bc->ioc3_sid[0] = IOC3_SID(IOC3_SUBSYS_MENET);
498 	bc->ioc3_sid[1] = IOC3_SID(IOC3_SUBSYS_MENET);
499 	bc->ioc3_sid[2] = IOC3_SID(IOC3_SUBSYS_MENET);
500 	bc->ioc3_sid[3] = IOC3_SID(IOC3_SUBSYS_MENET4);
501 }
502 
503 static void bridge_setup_io7(struct bridge_controller *bc)
504 {
505 	bc->ioc3_sid[4] = IOC3_SID(IOC3_SUBSYS_IO7);
506 }
507 
508 static void bridge_setup_io8(struct bridge_controller *bc)
509 {
510 	bc->ioc3_sid[4] = IOC3_SID(IOC3_SUBSYS_IO8);
511 }
512 
513 static void bridge_setup_io9(struct bridge_controller *bc)
514 {
515 	bc->ioc3_sid[1] = IOC3_SID(IOC3_SUBSYS_IO9);
516 }
517 
518 static void bridge_setup_ip34_fuel_sysboard(struct bridge_controller *bc)
519 {
520 	bc->ioc3_sid[4] = IOC3_SID(IOC3_SUBSYS_IP34_SYSBOARD);
521 }
522 
523 #define BRIDGE_BOARD_SETUP(_partno, _setup)	\
524 	{ .match = _partno, .setup = _setup }
525 
526 static const struct {
527 	char *match;
528 	void (*setup)(struct bridge_controller *bc);
529 } bridge_ioc3_devid[] = {
530 	BRIDGE_BOARD_SETUP("030-0734-", bridge_setup_ip27_baseio6g),
531 	BRIDGE_BOARD_SETUP("030-0880-", bridge_setup_ip27_baseio6g),
532 	BRIDGE_BOARD_SETUP("030-1023-", bridge_setup_ip27_baseio),
533 	BRIDGE_BOARD_SETUP("030-1124-", bridge_setup_ip27_baseio),
534 	BRIDGE_BOARD_SETUP("030-1025-", bridge_setup_ip29_baseio),
535 	BRIDGE_BOARD_SETUP("030-1244-", bridge_setup_ip29_baseio),
536 	BRIDGE_BOARD_SETUP("030-1389-", bridge_setup_ip29_baseio),
537 	BRIDGE_BOARD_SETUP("030-0887-", bridge_setup_ip30_sysboard),
538 	BRIDGE_BOARD_SETUP("030-1467-", bridge_setup_ip30_sysboard),
539 	BRIDGE_BOARD_SETUP("030-0873-", bridge_setup_menet),
540 	BRIDGE_BOARD_SETUP("030-1557-", bridge_setup_io7),
541 	BRIDGE_BOARD_SETUP("030-1673-", bridge_setup_io8),
542 	BRIDGE_BOARD_SETUP("030-1771-", bridge_setup_io9),
543 	BRIDGE_BOARD_SETUP("030-1707-", bridge_setup_ip34_fuel_sysboard),
544 };
545 
546 static void bridge_setup_board(struct bridge_controller *bc, char *partnum)
547 {
548 	int i;
549 
550 	for (i = 0; i < ARRAY_SIZE(bridge_ioc3_devid); i++)
551 		if (!strncmp(partnum, bridge_ioc3_devid[i].match,
552 			     strlen(bridge_ioc3_devid[i].match))) {
553 			bridge_ioc3_devid[i].setup(bc);
554 		}
555 }
556 
557 static int bridge_nvmem_match(struct device *dev, const void *data)
558 {
559 	const char *name = dev_name(dev);
560 	const char *prefix = data;
561 
562 	if (strlen(name) < strlen(prefix))
563 		return 0;
564 
565 	return memcmp(prefix, dev_name(dev), strlen(prefix)) == 0;
566 }
567 
568 static int bridge_get_partnum(u64 baddr, char *partnum)
569 {
570 	struct nvmem_device *nvmem;
571 	char prefix[24];
572 	u8 prom[64];
573 	int i, j;
574 	int ret;
575 
576 	snprintf(prefix, sizeof(prefix), "bridge-%012llx-0b-", baddr);
577 
578 	nvmem = nvmem_device_find(prefix, bridge_nvmem_match);
579 	if (IS_ERR(nvmem))
580 		return PTR_ERR(nvmem);
581 
582 	ret = nvmem_device_read(nvmem, 0, 64, prom);
583 	nvmem_device_put(nvmem);
584 
585 	if (ret != 64)
586 		return ret;
587 
588 	if (crc16(CRC16_INIT, prom, 32) != CRC16_VALID ||
589 	    crc16(CRC16_INIT, prom + 32, 32) != CRC16_VALID)
590 		return -EINVAL;
591 
592 	/* Assemble part number */
593 	j = 0;
594 	for (i = 0; i < 19; i++)
595 		if (prom[i + 11] != ' ')
596 			partnum[j++] = prom[i + 11];
597 
598 	for (i = 0; i < 6; i++)
599 		if (prom[i + 32] != ' ')
600 			partnum[j++] = prom[i + 32];
601 
602 	partnum[j] = 0;
603 
604 	return 0;
605 }
606 
607 static int bridge_probe(struct platform_device *pdev)
608 {
609 	struct xtalk_bridge_platform_data *bd = dev_get_platdata(&pdev->dev);
610 	struct device *dev = &pdev->dev;
611 	struct bridge_controller *bc;
612 	struct pci_host_bridge *host;
613 	struct irq_domain *domain, *parent;
614 	struct fwnode_handle *fn;
615 	char partnum[26];
616 	int slot;
617 	int err;
618 
619 	/* get part number from one wire prom */
620 	if (bridge_get_partnum(virt_to_phys((void *)bd->bridge_addr), partnum))
621 		return -EPROBE_DEFER; /* not available yet */
622 
623 	parent = irq_get_default_host();
624 	if (!parent)
625 		return -ENODEV;
626 	fn = irq_domain_alloc_named_fwnode("BRIDGE");
627 	if (!fn)
628 		return -ENOMEM;
629 	domain = irq_domain_create_hierarchy(parent, 0, 8, fn,
630 					     &bridge_domain_ops, NULL);
631 	if (!domain) {
632 		irq_domain_free_fwnode(fn);
633 		return -ENOMEM;
634 	}
635 
636 	pci_set_flags(PCI_PROBE_ONLY);
637 
638 	host = devm_pci_alloc_host_bridge(dev, sizeof(*bc));
639 	if (!host) {
640 		err = -ENOMEM;
641 		goto err_remove_domain;
642 	}
643 
644 	bc = pci_host_bridge_priv(host);
645 
646 	bc->busn.name		= "Bridge PCI busn";
647 	bc->busn.start		= 0;
648 	bc->busn.end		= 0xff;
649 	bc->busn.flags		= IORESOURCE_BUS;
650 
651 	bc->domain		= domain;
652 
653 	pci_add_resource_offset(&host->windows, &bd->mem, bd->mem_offset);
654 	pci_add_resource_offset(&host->windows, &bd->io, bd->io_offset);
655 	pci_add_resource(&host->windows, &bc->busn);
656 
657 	err = devm_request_pci_bus_resources(dev, &host->windows);
658 	if (err < 0)
659 		goto err_free_resource;
660 
661 	bc->nasid = bd->nasid;
662 
663 	bc->baddr = (u64)bd->masterwid << 60 | PCI64_ATTR_BAR;
664 	bc->base = (struct bridge_regs *)bd->bridge_addr;
665 	bc->intr_addr = bd->intr_addr;
666 
667 	/*
668 	 * Clear all pending interrupts.
669 	 */
670 	bridge_write(bc, b_int_rst_stat, BRIDGE_IRR_ALL_CLR);
671 
672 	/*
673 	 * Until otherwise set up, assume all interrupts are from slot 0
674 	 */
675 	bridge_write(bc, b_int_device, 0x0);
676 
677 	/*
678 	 * disable swapping for big windows
679 	 */
680 	bridge_clr(bc, b_wid_control,
681 		   BRIDGE_CTRL_IO_SWAP | BRIDGE_CTRL_MEM_SWAP);
682 #ifdef CONFIG_PAGE_SIZE_4KB
683 	bridge_clr(bc, b_wid_control, BRIDGE_CTRL_PAGE_SIZE);
684 #else /* 16kB or larger */
685 	bridge_set(bc, b_wid_control, BRIDGE_CTRL_PAGE_SIZE);
686 #endif
687 
688 	/*
689 	 * Hmm...  IRIX sets additional bits in the address which
690 	 * are documented as reserved in the bridge docs.
691 	 */
692 	bridge_write(bc, b_wid_int_upper,
693 		     ((bc->intr_addr >> 32) & 0xffff) | (bd->masterwid << 16));
694 	bridge_write(bc, b_wid_int_lower, bc->intr_addr & 0xffffffff);
695 	bridge_write(bc, b_dir_map, (bd->masterwid << 20));	/* DMA */
696 	bridge_write(bc, b_int_enable, 0);
697 
698 	for (slot = 0; slot < 8; slot++) {
699 		bridge_set(bc, b_device[slot].reg, BRIDGE_DEV_SWAP_DIR);
700 		bc->pci_int[slot][0] = -1;
701 		bc->pci_int[slot][1] = -1;
702 		/* default interrupt pin mapping */
703 		bc->int_mapping[slot][0] = slot;
704 		bc->int_mapping[slot][1] = slot ^ 4;
705 	}
706 	bridge_read(bc, b_wid_tflush);	  /* wait until Bridge PIO complete */
707 
708 	bridge_setup_board(bc, partnum);
709 
710 	host->dev.parent = dev;
711 	host->sysdata = bc;
712 	host->busnr = 0;
713 	host->ops = &bridge_pci_ops;
714 	host->map_irq = bridge_map_irq;
715 	host->swizzle_irq = pci_common_swizzle;
716 
717 	err = pci_scan_root_bus_bridge(host);
718 	if (err < 0)
719 		goto err_free_resource;
720 
721 	pci_bus_claim_resources(host->bus);
722 	pci_bus_add_devices(host->bus);
723 
724 	platform_set_drvdata(pdev, host->bus);
725 
726 	return 0;
727 
728 err_free_resource:
729 	pci_free_resource_list(&host->windows);
730 err_remove_domain:
731 	irq_domain_remove(domain);
732 	irq_domain_free_fwnode(fn);
733 	return err;
734 }
735 
736 static void bridge_remove(struct platform_device *pdev)
737 {
738 	struct pci_bus *bus = platform_get_drvdata(pdev);
739 	struct bridge_controller *bc = BRIDGE_CONTROLLER(bus);
740 	struct fwnode_handle *fn = bc->domain->fwnode;
741 
742 	irq_domain_remove(bc->domain);
743 	irq_domain_free_fwnode(fn);
744 	pci_lock_rescan_remove();
745 	pci_stop_root_bus(bus);
746 	pci_remove_root_bus(bus);
747 	pci_unlock_rescan_remove();
748 }
749 
750 static struct platform_driver bridge_driver = {
751 	.probe = bridge_probe,
752 	.remove_new = bridge_remove,
753 	.driver = {
754 		.name = "xtalk-bridge",
755 	}
756 };
757 
758 builtin_platform_driver(bridge_driver);
759