xref: /openbmc/linux/arch/mips/pci/pci-rt3883.c (revision b830f94f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Ralink RT3662/RT3883 SoC PCI support
4  *
5  *  Copyright (C) 2011-2013 Gabor Juhos <juhosg@openwrt.org>
6  *
7  *  Parts of this file are based on Ralink's 2.6.21 BSP
8  */
9 
10 #include <linux/types.h>
11 #include <linux/pci.h>
12 #include <linux/io.h>
13 #include <linux/init.h>
14 #include <linux/delay.h>
15 #include <linux/interrupt.h>
16 #include <linux/of.h>
17 #include <linux/of_irq.h>
18 #include <linux/of_pci.h>
19 #include <linux/platform_device.h>
20 
21 #include <asm/mach-ralink/rt3883.h>
22 #include <asm/mach-ralink/ralink_regs.h>
23 
24 #define RT3883_MEMORY_BASE		0x00000000
25 #define RT3883_MEMORY_SIZE		0x02000000
26 
27 #define RT3883_PCI_REG_PCICFG		0x00
28 #define   RT3883_PCICFG_P2P_BR_DEVNUM_M 0xf
29 #define   RT3883_PCICFG_P2P_BR_DEVNUM_S 16
30 #define   RT3883_PCICFG_PCIRST		BIT(1)
31 #define RT3883_PCI_REG_PCIRAW		0x04
32 #define RT3883_PCI_REG_PCIINT		0x08
33 #define RT3883_PCI_REG_PCIENA		0x0c
34 
35 #define RT3883_PCI_REG_CFGADDR		0x20
36 #define RT3883_PCI_REG_CFGDATA		0x24
37 #define RT3883_PCI_REG_MEMBASE		0x28
38 #define RT3883_PCI_REG_IOBASE		0x2c
39 #define RT3883_PCI_REG_ARBCTL		0x80
40 
41 #define RT3883_PCI_REG_BASE(_x)		(0x1000 + (_x) * 0x1000)
42 #define RT3883_PCI_REG_BAR0SETUP(_x)	(RT3883_PCI_REG_BASE((_x)) + 0x10)
43 #define RT3883_PCI_REG_IMBASEBAR0(_x)	(RT3883_PCI_REG_BASE((_x)) + 0x18)
44 #define RT3883_PCI_REG_ID(_x)		(RT3883_PCI_REG_BASE((_x)) + 0x30)
45 #define RT3883_PCI_REG_CLASS(_x)	(RT3883_PCI_REG_BASE((_x)) + 0x34)
46 #define RT3883_PCI_REG_SUBID(_x)	(RT3883_PCI_REG_BASE((_x)) + 0x38)
47 #define RT3883_PCI_REG_STATUS(_x)	(RT3883_PCI_REG_BASE((_x)) + 0x50)
48 
49 #define RT3883_PCI_MODE_NONE	0
50 #define RT3883_PCI_MODE_PCI	BIT(0)
51 #define RT3883_PCI_MODE_PCIE	BIT(1)
52 #define RT3883_PCI_MODE_BOTH	(RT3883_PCI_MODE_PCI | RT3883_PCI_MODE_PCIE)
53 
54 #define RT3883_PCI_IRQ_COUNT	32
55 
56 #define RT3883_P2P_BR_DEVNUM	1
57 
58 struct rt3883_pci_controller {
59 	void __iomem *base;
60 
61 	struct device_node *intc_of_node;
62 	struct irq_domain *irq_domain;
63 
64 	struct pci_controller pci_controller;
65 	struct resource io_res;
66 	struct resource mem_res;
67 
68 	bool pcie_ready;
69 };
70 
71 static inline struct rt3883_pci_controller *
72 pci_bus_to_rt3883_controller(struct pci_bus *bus)
73 {
74 	struct pci_controller *hose;
75 
76 	hose = (struct pci_controller *) bus->sysdata;
77 	return container_of(hose, struct rt3883_pci_controller, pci_controller);
78 }
79 
80 static inline u32 rt3883_pci_r32(struct rt3883_pci_controller *rpc,
81 				 unsigned reg)
82 {
83 	return ioread32(rpc->base + reg);
84 }
85 
86 static inline void rt3883_pci_w32(struct rt3883_pci_controller *rpc,
87 				  u32 val, unsigned reg)
88 {
89 	iowrite32(val, rpc->base + reg);
90 }
91 
92 static inline u32 rt3883_pci_get_cfgaddr(unsigned int bus, unsigned int slot,
93 					 unsigned int func, unsigned int where)
94 {
95 	return (bus << 16) | (slot << 11) | (func << 8) | (where & 0xfc) |
96 	       0x80000000;
97 }
98 
99 static u32 rt3883_pci_read_cfg32(struct rt3883_pci_controller *rpc,
100 			       unsigned bus, unsigned slot,
101 			       unsigned func, unsigned reg)
102 {
103 	unsigned long flags;
104 	u32 address;
105 	u32 ret;
106 
107 	address = rt3883_pci_get_cfgaddr(bus, slot, func, reg);
108 
109 	rt3883_pci_w32(rpc, address, RT3883_PCI_REG_CFGADDR);
110 	ret = rt3883_pci_r32(rpc, RT3883_PCI_REG_CFGDATA);
111 
112 	return ret;
113 }
114 
115 static void rt3883_pci_write_cfg32(struct rt3883_pci_controller *rpc,
116 				 unsigned bus, unsigned slot,
117 				 unsigned func, unsigned reg, u32 val)
118 {
119 	unsigned long flags;
120 	u32 address;
121 
122 	address = rt3883_pci_get_cfgaddr(bus, slot, func, reg);
123 
124 	rt3883_pci_w32(rpc, address, RT3883_PCI_REG_CFGADDR);
125 	rt3883_pci_w32(rpc, val, RT3883_PCI_REG_CFGDATA);
126 }
127 
128 static void rt3883_pci_irq_handler(struct irq_desc *desc)
129 {
130 	struct rt3883_pci_controller *rpc;
131 	u32 pending;
132 
133 	rpc = irq_desc_get_handler_data(desc);
134 
135 	pending = rt3883_pci_r32(rpc, RT3883_PCI_REG_PCIINT) &
136 		  rt3883_pci_r32(rpc, RT3883_PCI_REG_PCIENA);
137 
138 	if (!pending) {
139 		spurious_interrupt();
140 		return;
141 	}
142 
143 	while (pending) {
144 		unsigned irq, bit = __ffs(pending);
145 
146 		irq = irq_find_mapping(rpc->irq_domain, bit);
147 		generic_handle_irq(irq);
148 
149 		pending &= ~BIT(bit);
150 	}
151 }
152 
153 static void rt3883_pci_irq_unmask(struct irq_data *d)
154 {
155 	struct rt3883_pci_controller *rpc;
156 	u32 t;
157 
158 	rpc = irq_data_get_irq_chip_data(d);
159 
160 	t = rt3883_pci_r32(rpc, RT3883_PCI_REG_PCIENA);
161 	rt3883_pci_w32(rpc, t | BIT(d->hwirq), RT3883_PCI_REG_PCIENA);
162 	/* flush write */
163 	rt3883_pci_r32(rpc, RT3883_PCI_REG_PCIENA);
164 }
165 
166 static void rt3883_pci_irq_mask(struct irq_data *d)
167 {
168 	struct rt3883_pci_controller *rpc;
169 	u32 t;
170 
171 	rpc = irq_data_get_irq_chip_data(d);
172 
173 	t = rt3883_pci_r32(rpc, RT3883_PCI_REG_PCIENA);
174 	rt3883_pci_w32(rpc, t & ~BIT(d->hwirq), RT3883_PCI_REG_PCIENA);
175 	/* flush write */
176 	rt3883_pci_r32(rpc, RT3883_PCI_REG_PCIENA);
177 }
178 
179 static struct irq_chip rt3883_pci_irq_chip = {
180 	.name		= "RT3883 PCI",
181 	.irq_mask	= rt3883_pci_irq_mask,
182 	.irq_unmask	= rt3883_pci_irq_unmask,
183 	.irq_mask_ack	= rt3883_pci_irq_mask,
184 };
185 
186 static int rt3883_pci_irq_map(struct irq_domain *d, unsigned int irq,
187 			      irq_hw_number_t hw)
188 {
189 	irq_set_chip_and_handler(irq, &rt3883_pci_irq_chip, handle_level_irq);
190 	irq_set_chip_data(irq, d->host_data);
191 
192 	return 0;
193 }
194 
195 static const struct irq_domain_ops rt3883_pci_irq_domain_ops = {
196 	.map = rt3883_pci_irq_map,
197 	.xlate = irq_domain_xlate_onecell,
198 };
199 
200 static int rt3883_pci_irq_init(struct device *dev,
201 			       struct rt3883_pci_controller *rpc)
202 {
203 	int irq;
204 
205 	irq = irq_of_parse_and_map(rpc->intc_of_node, 0);
206 	if (irq == 0) {
207 		dev_err(dev, "%pOF has no IRQ", rpc->intc_of_node);
208 		return -EINVAL;
209 	}
210 
211 	/* disable all interrupts */
212 	rt3883_pci_w32(rpc, 0, RT3883_PCI_REG_PCIENA);
213 
214 	rpc->irq_domain =
215 		irq_domain_add_linear(rpc->intc_of_node, RT3883_PCI_IRQ_COUNT,
216 				      &rt3883_pci_irq_domain_ops,
217 				      rpc);
218 	if (!rpc->irq_domain) {
219 		dev_err(dev, "unable to add IRQ domain\n");
220 		return -ENODEV;
221 	}
222 
223 	irq_set_chained_handler_and_data(irq, rt3883_pci_irq_handler, rpc);
224 
225 	return 0;
226 }
227 
228 static int rt3883_pci_config_read(struct pci_bus *bus, unsigned int devfn,
229 				  int where, int size, u32 *val)
230 {
231 	struct rt3883_pci_controller *rpc;
232 	unsigned long flags;
233 	u32 address;
234 	u32 data;
235 
236 	rpc = pci_bus_to_rt3883_controller(bus);
237 
238 	if (!rpc->pcie_ready && bus->number == 1)
239 		return PCIBIOS_DEVICE_NOT_FOUND;
240 
241 	address = rt3883_pci_get_cfgaddr(bus->number, PCI_SLOT(devfn),
242 					 PCI_FUNC(devfn), where);
243 
244 	rt3883_pci_w32(rpc, address, RT3883_PCI_REG_CFGADDR);
245 	data = rt3883_pci_r32(rpc, RT3883_PCI_REG_CFGDATA);
246 
247 	switch (size) {
248 	case 1:
249 		*val = (data >> ((where & 3) << 3)) & 0xff;
250 		break;
251 	case 2:
252 		*val = (data >> ((where & 3) << 3)) & 0xffff;
253 		break;
254 	case 4:
255 		*val = data;
256 		break;
257 	}
258 
259 	return PCIBIOS_SUCCESSFUL;
260 }
261 
262 static int rt3883_pci_config_write(struct pci_bus *bus, unsigned int devfn,
263 				   int where, int size, u32 val)
264 {
265 	struct rt3883_pci_controller *rpc;
266 	unsigned long flags;
267 	u32 address;
268 	u32 data;
269 
270 	rpc = pci_bus_to_rt3883_controller(bus);
271 
272 	if (!rpc->pcie_ready && bus->number == 1)
273 		return PCIBIOS_DEVICE_NOT_FOUND;
274 
275 	address = rt3883_pci_get_cfgaddr(bus->number, PCI_SLOT(devfn),
276 					 PCI_FUNC(devfn), where);
277 
278 	rt3883_pci_w32(rpc, address, RT3883_PCI_REG_CFGADDR);
279 	data = rt3883_pci_r32(rpc, RT3883_PCI_REG_CFGDATA);
280 
281 	switch (size) {
282 	case 1:
283 		data = (data & ~(0xff << ((where & 3) << 3))) |
284 		       (val << ((where & 3) << 3));
285 		break;
286 	case 2:
287 		data = (data & ~(0xffff << ((where & 3) << 3))) |
288 		       (val << ((where & 3) << 3));
289 		break;
290 	case 4:
291 		data = val;
292 		break;
293 	}
294 
295 	rt3883_pci_w32(rpc, data, RT3883_PCI_REG_CFGDATA);
296 
297 	return PCIBIOS_SUCCESSFUL;
298 }
299 
300 static struct pci_ops rt3883_pci_ops = {
301 	.read	= rt3883_pci_config_read,
302 	.write	= rt3883_pci_config_write,
303 };
304 
305 static void rt3883_pci_preinit(struct rt3883_pci_controller *rpc, unsigned mode)
306 {
307 	u32 syscfg1;
308 	u32 rstctrl;
309 	u32 clkcfg1;
310 	u32 t;
311 
312 	rstctrl = rt_sysc_r32(RT3883_SYSC_REG_RSTCTRL);
313 	syscfg1 = rt_sysc_r32(RT3883_SYSC_REG_SYSCFG1);
314 	clkcfg1 = rt_sysc_r32(RT3883_SYSC_REG_CLKCFG1);
315 
316 	if (mode & RT3883_PCI_MODE_PCIE) {
317 		rstctrl |= RT3883_RSTCTRL_PCIE;
318 		rt_sysc_w32(rstctrl, RT3883_SYSC_REG_RSTCTRL);
319 
320 		/* setup PCI PAD drive mode */
321 		syscfg1 &= ~(0x30);
322 		syscfg1 |= (2 << 4);
323 		rt_sysc_w32(syscfg1, RT3883_SYSC_REG_SYSCFG1);
324 
325 		t = rt_sysc_r32(RT3883_SYSC_REG_PCIE_CLK_GEN0);
326 		t &= ~BIT(31);
327 		rt_sysc_w32(t, RT3883_SYSC_REG_PCIE_CLK_GEN0);
328 
329 		t = rt_sysc_r32(RT3883_SYSC_REG_PCIE_CLK_GEN1);
330 		t &= 0x80ffffff;
331 		rt_sysc_w32(t, RT3883_SYSC_REG_PCIE_CLK_GEN1);
332 
333 		t = rt_sysc_r32(RT3883_SYSC_REG_PCIE_CLK_GEN1);
334 		t |= 0xa << 24;
335 		rt_sysc_w32(t, RT3883_SYSC_REG_PCIE_CLK_GEN1);
336 
337 		t = rt_sysc_r32(RT3883_SYSC_REG_PCIE_CLK_GEN0);
338 		t |= BIT(31);
339 		rt_sysc_w32(t, RT3883_SYSC_REG_PCIE_CLK_GEN0);
340 
341 		msleep(50);
342 
343 		rstctrl &= ~RT3883_RSTCTRL_PCIE;
344 		rt_sysc_w32(rstctrl, RT3883_SYSC_REG_RSTCTRL);
345 	}
346 
347 	syscfg1 |= (RT3883_SYSCFG1_PCIE_RC_MODE | RT3883_SYSCFG1_PCI_HOST_MODE);
348 
349 	clkcfg1 &= ~(RT3883_CLKCFG1_PCI_CLK_EN | RT3883_CLKCFG1_PCIE_CLK_EN);
350 
351 	if (mode & RT3883_PCI_MODE_PCI) {
352 		clkcfg1 |= RT3883_CLKCFG1_PCI_CLK_EN;
353 		rstctrl &= ~RT3883_RSTCTRL_PCI;
354 	}
355 
356 	if (mode & RT3883_PCI_MODE_PCIE) {
357 		clkcfg1 |= RT3883_CLKCFG1_PCIE_CLK_EN;
358 		rstctrl &= ~RT3883_RSTCTRL_PCIE;
359 	}
360 
361 	rt_sysc_w32(syscfg1, RT3883_SYSC_REG_SYSCFG1);
362 	rt_sysc_w32(rstctrl, RT3883_SYSC_REG_RSTCTRL);
363 	rt_sysc_w32(clkcfg1, RT3883_SYSC_REG_CLKCFG1);
364 
365 	msleep(500);
366 
367 	/*
368 	 * setup the device number of the P2P bridge
369 	 * and de-assert the reset line
370 	 */
371 	t = (RT3883_P2P_BR_DEVNUM << RT3883_PCICFG_P2P_BR_DEVNUM_S);
372 	rt3883_pci_w32(rpc, t, RT3883_PCI_REG_PCICFG);
373 
374 	/* flush write */
375 	rt3883_pci_r32(rpc, RT3883_PCI_REG_PCICFG);
376 	msleep(500);
377 
378 	if (mode & RT3883_PCI_MODE_PCIE) {
379 		msleep(500);
380 
381 		t = rt3883_pci_r32(rpc, RT3883_PCI_REG_STATUS(1));
382 
383 		rpc->pcie_ready = t & BIT(0);
384 
385 		if (!rpc->pcie_ready) {
386 			/* reset the PCIe block */
387 			t = rt_sysc_r32(RT3883_SYSC_REG_RSTCTRL);
388 			t |= RT3883_RSTCTRL_PCIE;
389 			rt_sysc_w32(t, RT3883_SYSC_REG_RSTCTRL);
390 			t &= ~RT3883_RSTCTRL_PCIE;
391 			rt_sysc_w32(t, RT3883_SYSC_REG_RSTCTRL);
392 
393 			/* turn off PCIe clock */
394 			t = rt_sysc_r32(RT3883_SYSC_REG_CLKCFG1);
395 			t &= ~RT3883_CLKCFG1_PCIE_CLK_EN;
396 			rt_sysc_w32(t, RT3883_SYSC_REG_CLKCFG1);
397 
398 			t = rt_sysc_r32(RT3883_SYSC_REG_PCIE_CLK_GEN0);
399 			t &= ~0xf000c080;
400 			rt_sysc_w32(t, RT3883_SYSC_REG_PCIE_CLK_GEN0);
401 		}
402 	}
403 
404 	/* enable PCI arbiter */
405 	rt3883_pci_w32(rpc, 0x79, RT3883_PCI_REG_ARBCTL);
406 }
407 
408 static int rt3883_pci_probe(struct platform_device *pdev)
409 {
410 	struct rt3883_pci_controller *rpc;
411 	struct device *dev = &pdev->dev;
412 	struct device_node *np = dev->of_node;
413 	struct resource *res;
414 	struct device_node *child;
415 	u32 val;
416 	int err;
417 	int mode;
418 
419 	rpc = devm_kzalloc(dev, sizeof(*rpc), GFP_KERNEL);
420 	if (!rpc)
421 		return -ENOMEM;
422 
423 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
424 	rpc->base = devm_ioremap_resource(dev, res);
425 	if (IS_ERR(rpc->base))
426 		return PTR_ERR(rpc->base);
427 
428 	/* find the interrupt controller child node */
429 	for_each_child_of_node(np, child) {
430 		if (of_get_property(child, "interrupt-controller", NULL)) {
431 			rpc->intc_of_node = child;
432 			break;
433 		}
434 	}
435 
436 	if (!rpc->intc_of_node) {
437 		dev_err(dev, "%pOF has no %s child node",
438 			rpc->intc_of_node,
439 			"interrupt controller");
440 		return -EINVAL;
441 	}
442 
443 	/* find the PCI host bridge child node */
444 	for_each_child_of_node(np, child) {
445 		if (of_node_is_type(child, "pci")) {
446 			rpc->pci_controller.of_node = child;
447 			break;
448 		}
449 	}
450 
451 	if (!rpc->pci_controller.of_node) {
452 		dev_err(dev, "%pOF has no %s child node",
453 			rpc->intc_of_node,
454 			"PCI host bridge");
455 		err = -EINVAL;
456 		goto err_put_intc_node;
457 	}
458 
459 	mode = RT3883_PCI_MODE_NONE;
460 	for_each_available_child_of_node(rpc->pci_controller.of_node, child) {
461 		int devfn;
462 
463 		if (!of_node_is_type(child, "pci"))
464 			continue;
465 
466 		devfn = of_pci_get_devfn(child);
467 		if (devfn < 0)
468 			continue;
469 
470 		switch (PCI_SLOT(devfn)) {
471 		case 1:
472 			mode |= RT3883_PCI_MODE_PCIE;
473 			break;
474 
475 		case 17:
476 		case 18:
477 			mode |= RT3883_PCI_MODE_PCI;
478 			break;
479 		}
480 	}
481 
482 	if (mode == RT3883_PCI_MODE_NONE) {
483 		dev_err(dev, "unable to determine PCI mode\n");
484 		err = -EINVAL;
485 		goto err_put_hb_node;
486 	}
487 
488 	dev_info(dev, "mode:%s%s\n",
489 		 (mode & RT3883_PCI_MODE_PCI) ? " PCI" : "",
490 		 (mode & RT3883_PCI_MODE_PCIE) ? " PCIe" : "");
491 
492 	rt3883_pci_preinit(rpc, mode);
493 
494 	rpc->pci_controller.pci_ops = &rt3883_pci_ops;
495 	rpc->pci_controller.io_resource = &rpc->io_res;
496 	rpc->pci_controller.mem_resource = &rpc->mem_res;
497 
498 	/* Load PCI I/O and memory resources from DT */
499 	pci_load_of_ranges(&rpc->pci_controller,
500 			   rpc->pci_controller.of_node);
501 
502 	rt3883_pci_w32(rpc, rpc->mem_res.start, RT3883_PCI_REG_MEMBASE);
503 	rt3883_pci_w32(rpc, rpc->io_res.start, RT3883_PCI_REG_IOBASE);
504 
505 	ioport_resource.start = rpc->io_res.start;
506 	ioport_resource.end = rpc->io_res.end;
507 
508 	/* PCI */
509 	rt3883_pci_w32(rpc, 0x03ff0000, RT3883_PCI_REG_BAR0SETUP(0));
510 	rt3883_pci_w32(rpc, RT3883_MEMORY_BASE, RT3883_PCI_REG_IMBASEBAR0(0));
511 	rt3883_pci_w32(rpc, 0x08021814, RT3883_PCI_REG_ID(0));
512 	rt3883_pci_w32(rpc, 0x00800001, RT3883_PCI_REG_CLASS(0));
513 	rt3883_pci_w32(rpc, 0x28801814, RT3883_PCI_REG_SUBID(0));
514 
515 	/* PCIe */
516 	rt3883_pci_w32(rpc, 0x03ff0000, RT3883_PCI_REG_BAR0SETUP(1));
517 	rt3883_pci_w32(rpc, RT3883_MEMORY_BASE, RT3883_PCI_REG_IMBASEBAR0(1));
518 	rt3883_pci_w32(rpc, 0x08021814, RT3883_PCI_REG_ID(1));
519 	rt3883_pci_w32(rpc, 0x06040001, RT3883_PCI_REG_CLASS(1));
520 	rt3883_pci_w32(rpc, 0x28801814, RT3883_PCI_REG_SUBID(1));
521 
522 	err = rt3883_pci_irq_init(dev, rpc);
523 	if (err)
524 		goto err_put_hb_node;
525 
526 	/* PCIe */
527 	val = rt3883_pci_read_cfg32(rpc, 0, 0x01, 0, PCI_COMMAND);
528 	val |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER;
529 	rt3883_pci_write_cfg32(rpc, 0, 0x01, 0, PCI_COMMAND, val);
530 
531 	/* PCI */
532 	val = rt3883_pci_read_cfg32(rpc, 0, 0x00, 0, PCI_COMMAND);
533 	val |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER;
534 	rt3883_pci_write_cfg32(rpc, 0, 0x00, 0, PCI_COMMAND, val);
535 
536 	if (mode == RT3883_PCI_MODE_PCIE) {
537 		rt3883_pci_w32(rpc, 0x03ff0001, RT3883_PCI_REG_BAR0SETUP(0));
538 		rt3883_pci_w32(rpc, 0x03ff0001, RT3883_PCI_REG_BAR0SETUP(1));
539 
540 		rt3883_pci_write_cfg32(rpc, 0, RT3883_P2P_BR_DEVNUM, 0,
541 				       PCI_BASE_ADDRESS_0,
542 				       RT3883_MEMORY_BASE);
543 		/* flush write */
544 		rt3883_pci_read_cfg32(rpc, 0, RT3883_P2P_BR_DEVNUM, 0,
545 				      PCI_BASE_ADDRESS_0);
546 	} else {
547 		rt3883_pci_write_cfg32(rpc, 0, RT3883_P2P_BR_DEVNUM, 0,
548 				       PCI_IO_BASE, 0x00000101);
549 	}
550 
551 	register_pci_controller(&rpc->pci_controller);
552 
553 	return 0;
554 
555 err_put_hb_node:
556 	of_node_put(rpc->pci_controller.of_node);
557 err_put_intc_node:
558 	of_node_put(rpc->intc_of_node);
559 	return err;
560 }
561 
562 int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
563 {
564 	return of_irq_parse_and_map_pci(dev, slot, pin);
565 }
566 
567 int pcibios_plat_dev_init(struct pci_dev *dev)
568 {
569 	return 0;
570 }
571 
572 static const struct of_device_id rt3883_pci_ids[] = {
573 	{ .compatible = "ralink,rt3883-pci" },
574 	{},
575 };
576 
577 static struct platform_driver rt3883_pci_driver = {
578 	.probe = rt3883_pci_probe,
579 	.driver = {
580 		.name = "rt3883-pci",
581 		.of_match_table = of_match_ptr(rt3883_pci_ids),
582 	},
583 };
584 
585 static int __init rt3883_pci_init(void)
586 {
587 	return platform_driver_register(&rt3883_pci_driver);
588 }
589 
590 postcore_initcall(rt3883_pci_init);
591