xref: /openbmc/linux/arch/parisc/kernel/drivers.c (revision 137c0118)
1 /*
2  * drivers.c
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version
7  * 2 of the License, or (at your option) any later version.
8  *
9  * Copyright (c) 1999 The Puffin Group
10  * Copyright (c) 2001 Matthew Wilcox for Hewlett Packard
11  * Copyright (c) 2001 Helge Deller <deller@gmx.de>
12  * Copyright (c) 2001,2002 Ryan Bradetich
13  * Copyright (c) 2004-2005 Thibaut VARENE <varenet@parisc-linux.org>
14  *
15  * The file handles registering devices and drivers, then matching them.
16  * It's the closest we get to a dating agency.
17  *
18  * If you're thinking about modifying this file, here are some gotchas to
19  * bear in mind:
20  *  - 715/Mirage device paths have a dummy device between Lasi and its children
21  *  - The EISA adapter may show up as a sibling or child of Wax
22  *  - Dino has an optionally functional serial port.  If firmware enables it,
23  *    it shows up as a child of Dino.  If firmware disables it, the buswalk
24  *    finds it and it shows up as a child of Cujo
25  *  - Dino has both parisc and pci devices as children
26  *  - parisc devices are discovered in a random order, including children
27  *    before parents in some cases.
28  */
29 
30 #include <linux/slab.h>
31 #include <linux/types.h>
32 #include <linux/kernel.h>
33 #include <linux/pci.h>
34 #include <linux/spinlock.h>
35 #include <linux/string.h>
36 #include <linux/export.h>
37 #include <asm/hardware.h>
38 #include <asm/io.h>
39 #include <asm/pdc.h>
40 #include <asm/parisc-device.h>
41 
42 /* See comments in include/asm-parisc/pci.h */
43 const struct dma_map_ops *hppa_dma_ops __read_mostly;
44 EXPORT_SYMBOL(hppa_dma_ops);
45 
46 static struct device root = {
47 	.init_name = "parisc",
48 };
49 
50 static inline int check_dev(struct device *dev)
51 {
52 	if (dev->bus == &parisc_bus_type) {
53 		struct parisc_device *pdev;
54 		pdev = to_parisc_device(dev);
55 		return pdev->id.hw_type != HPHW_FAULTY;
56 	}
57 	return 1;
58 }
59 
60 static struct device *
61 parse_tree_node(struct device *parent, int index, struct hardware_path *modpath);
62 
63 struct recurse_struct {
64 	void * obj;
65 	int (*fn)(struct device *, void *);
66 };
67 
68 static int descend_children(struct device * dev, void * data)
69 {
70 	struct recurse_struct * recurse_data = (struct recurse_struct *)data;
71 
72 	if (recurse_data->fn(dev, recurse_data->obj))
73 		return 1;
74 	else
75 		return device_for_each_child(dev, recurse_data, descend_children);
76 }
77 
78 /**
79  *	for_each_padev - Iterate over all devices in the tree
80  *	@fn:	Function to call for each device.
81  *	@data:	Data to pass to the called function.
82  *
83  *	This performs a depth-first traversal of the tree, calling the
84  *	function passed for each node.  It calls the function for parents
85  *	before children.
86  */
87 
88 static int for_each_padev(int (*fn)(struct device *, void *), void * data)
89 {
90 	struct recurse_struct recurse_data = {
91 		.obj	= data,
92 		.fn	= fn,
93 	};
94 	return device_for_each_child(&root, &recurse_data, descend_children);
95 }
96 
97 /**
98  * match_device - Report whether this driver can handle this device
99  * @driver: the PA-RISC driver to try
100  * @dev: the PA-RISC device to try
101  */
102 static int match_device(struct parisc_driver *driver, struct parisc_device *dev)
103 {
104 	const struct parisc_device_id *ids;
105 
106 	for (ids = driver->id_table; ids->sversion; ids++) {
107 		if ((ids->sversion != SVERSION_ANY_ID) &&
108 		    (ids->sversion != dev->id.sversion))
109 			continue;
110 
111 		if ((ids->hw_type != HWTYPE_ANY_ID) &&
112 		    (ids->hw_type != dev->id.hw_type))
113 			continue;
114 
115 		if ((ids->hversion != HVERSION_ANY_ID) &&
116 		    (ids->hversion != dev->id.hversion))
117 			continue;
118 
119 		return 1;
120 	}
121 	return 0;
122 }
123 
124 static int parisc_driver_probe(struct device *dev)
125 {
126 	int rc;
127 	struct parisc_device *pa_dev = to_parisc_device(dev);
128 	struct parisc_driver *pa_drv = to_parisc_driver(dev->driver);
129 
130 	rc = pa_drv->probe(pa_dev);
131 
132 	if (!rc)
133 		pa_dev->driver = pa_drv;
134 
135 	return rc;
136 }
137 
138 static int __exit parisc_driver_remove(struct device *dev)
139 {
140 	struct parisc_device *pa_dev = to_parisc_device(dev);
141 	struct parisc_driver *pa_drv = to_parisc_driver(dev->driver);
142 	if (pa_drv->remove)
143 		pa_drv->remove(pa_dev);
144 
145 	return 0;
146 }
147 
148 
149 /**
150  * register_parisc_driver - Register this driver if it can handle a device
151  * @driver: the PA-RISC driver to try
152  */
153 int register_parisc_driver(struct parisc_driver *driver)
154 {
155 	/* FIXME: we need this because apparently the sti
156 	 * driver can be registered twice */
157 	if(driver->drv.name) {
158 		printk(KERN_WARNING
159 		       "BUG: skipping previously registered driver %s\n",
160 		       driver->name);
161 		return 1;
162 	}
163 
164 	if (!driver->probe) {
165 		printk(KERN_WARNING
166 		       "BUG: driver %s has no probe routine\n",
167 		       driver->name);
168 		return 1;
169 	}
170 
171 	driver->drv.bus = &parisc_bus_type;
172 
173 	/* We install our own probe and remove routines */
174 	WARN_ON(driver->drv.probe != NULL);
175 	WARN_ON(driver->drv.remove != NULL);
176 
177 	driver->drv.name = driver->name;
178 
179 	return driver_register(&driver->drv);
180 }
181 EXPORT_SYMBOL(register_parisc_driver);
182 
183 
184 struct match_count {
185 	struct parisc_driver * driver;
186 	int count;
187 };
188 
189 static int match_and_count(struct device * dev, void * data)
190 {
191 	struct match_count * m = data;
192 	struct parisc_device * pdev = to_parisc_device(dev);
193 
194 	if (check_dev(dev)) {
195 		if (match_device(m->driver, pdev))
196 			m->count++;
197 	}
198 	return 0;
199 }
200 
201 /**
202  * count_parisc_driver - count # of devices this driver would match
203  * @driver: the PA-RISC driver to try
204  *
205  * Use by IOMMU support to "guess" the right size IOPdir.
206  * Formula is something like memsize/(num_iommu * entry_size).
207  */
208 int __init count_parisc_driver(struct parisc_driver *driver)
209 {
210 	struct match_count m = {
211 		.driver	= driver,
212 		.count	= 0,
213 	};
214 
215 	for_each_padev(match_and_count, &m);
216 
217 	return m.count;
218 }
219 
220 
221 
222 /**
223  * unregister_parisc_driver - Unregister this driver from the list of drivers
224  * @driver: the PA-RISC driver to unregister
225  */
226 int unregister_parisc_driver(struct parisc_driver *driver)
227 {
228 	driver_unregister(&driver->drv);
229 	return 0;
230 }
231 EXPORT_SYMBOL(unregister_parisc_driver);
232 
233 struct find_data {
234 	unsigned long hpa;
235 	struct parisc_device * dev;
236 };
237 
238 static int find_device(struct device * dev, void * data)
239 {
240 	struct parisc_device * pdev = to_parisc_device(dev);
241 	struct find_data * d = (struct find_data*)data;
242 
243 	if (check_dev(dev)) {
244 		if (pdev->hpa.start == d->hpa) {
245 			d->dev = pdev;
246 			return 1;
247 		}
248 	}
249 	return 0;
250 }
251 
252 static struct parisc_device *find_device_by_addr(unsigned long hpa)
253 {
254 	struct find_data d = {
255 		.hpa	= hpa,
256 	};
257 	int ret;
258 
259 	ret = for_each_padev(find_device, &d);
260 	return ret ? d.dev : NULL;
261 }
262 
263 /**
264  * find_pa_parent_type - Find a parent of a specific type
265  * @dev: The device to start searching from
266  * @type: The device type to search for.
267  *
268  * Walks up the device tree looking for a device of the specified type.
269  * If it finds it, it returns it.  If not, it returns NULL.
270  */
271 const struct parisc_device *
272 find_pa_parent_type(const struct parisc_device *padev, int type)
273 {
274 	const struct device *dev = &padev->dev;
275 	while (dev != &root) {
276 		struct parisc_device *candidate = to_parisc_device(dev);
277 		if (candidate->id.hw_type == type)
278 			return candidate;
279 		dev = dev->parent;
280 	}
281 
282 	return NULL;
283 }
284 
285 /*
286  * get_node_path fills in @path with the firmware path to the device.
287  * Note that if @node is a parisc device, we don't fill in the 'mod' field.
288  * This is because both callers pass the parent and fill in the mod
289  * themselves.  If @node is a PCI device, we do fill it in, even though this
290  * is inconsistent.
291  */
292 static void get_node_path(struct device *dev, struct hardware_path *path)
293 {
294 	int i = 5;
295 	memset(&path->bc, -1, 6);
296 
297 	if (dev_is_pci(dev)) {
298 		unsigned int devfn = to_pci_dev(dev)->devfn;
299 		path->mod = PCI_FUNC(devfn);
300 		path->bc[i--] = PCI_SLOT(devfn);
301 		dev = dev->parent;
302 	}
303 
304 	while (dev != &root) {
305 		if (dev_is_pci(dev)) {
306 			unsigned int devfn = to_pci_dev(dev)->devfn;
307 			path->bc[i--] = PCI_SLOT(devfn) | (PCI_FUNC(devfn)<< 5);
308 		} else if (dev->bus == &parisc_bus_type) {
309 			path->bc[i--] = to_parisc_device(dev)->hw_path;
310 		}
311 		dev = dev->parent;
312 	}
313 }
314 
315 static char *print_hwpath(struct hardware_path *path, char *output)
316 {
317 	int i;
318 	for (i = 0; i < 6; i++) {
319 		if (path->bc[i] == -1)
320 			continue;
321 		output += sprintf(output, "%u/", (unsigned char) path->bc[i]);
322 	}
323 	output += sprintf(output, "%u", (unsigned char) path->mod);
324 	return output;
325 }
326 
327 /**
328  * print_pa_hwpath - Returns hardware path for PA devices
329  * dev: The device to return the path for
330  * output: Pointer to a previously-allocated array to place the path in.
331  *
332  * This function fills in the output array with a human-readable path
333  * to a PA device.  This string is compatible with that used by PDC, and
334  * may be printed on the outside of the box.
335  */
336 char *print_pa_hwpath(struct parisc_device *dev, char *output)
337 {
338 	struct hardware_path path;
339 
340 	get_node_path(dev->dev.parent, &path);
341 	path.mod = dev->hw_path;
342 	return print_hwpath(&path, output);
343 }
344 EXPORT_SYMBOL(print_pa_hwpath);
345 
346 #if defined(CONFIG_PCI) || defined(CONFIG_ISA)
347 /**
348  * get_pci_node_path - Determines the hardware path for a PCI device
349  * @pdev: The device to return the path for
350  * @path: Pointer to a previously-allocated array to place the path in.
351  *
352  * This function fills in the hardware_path structure with the route to
353  * the specified PCI device.  This structure is suitable for passing to
354  * PDC calls.
355  */
356 void get_pci_node_path(struct pci_dev *pdev, struct hardware_path *path)
357 {
358 	get_node_path(&pdev->dev, path);
359 }
360 EXPORT_SYMBOL(get_pci_node_path);
361 
362 /**
363  * print_pci_hwpath - Returns hardware path for PCI devices
364  * dev: The device to return the path for
365  * output: Pointer to a previously-allocated array to place the path in.
366  *
367  * This function fills in the output array with a human-readable path
368  * to a PCI device.  This string is compatible with that used by PDC, and
369  * may be printed on the outside of the box.
370  */
371 char *print_pci_hwpath(struct pci_dev *dev, char *output)
372 {
373 	struct hardware_path path;
374 
375 	get_pci_node_path(dev, &path);
376 	return print_hwpath(&path, output);
377 }
378 EXPORT_SYMBOL(print_pci_hwpath);
379 
380 #endif /* defined(CONFIG_PCI) || defined(CONFIG_ISA) */
381 
382 static void setup_bus_id(struct parisc_device *padev)
383 {
384 	struct hardware_path path;
385 	char name[28];
386 	char *output = name;
387 	int i;
388 
389 	get_node_path(padev->dev.parent, &path);
390 
391 	for (i = 0; i < 6; i++) {
392 		if (path.bc[i] == -1)
393 			continue;
394 		output += sprintf(output, "%u:", (unsigned char) path.bc[i]);
395 	}
396 	sprintf(output, "%u", (unsigned char) padev->hw_path);
397 	dev_set_name(&padev->dev, name);
398 }
399 
400 struct parisc_device * __init create_tree_node(char id, struct device *parent)
401 {
402 	struct parisc_device *dev = kzalloc(sizeof(*dev), GFP_KERNEL);
403 	if (!dev)
404 		return NULL;
405 
406 	dev->hw_path = id;
407 	dev->id.hw_type = HPHW_FAULTY;
408 
409 	dev->dev.parent = parent;
410 	setup_bus_id(dev);
411 
412 	dev->dev.bus = &parisc_bus_type;
413 	dev->dma_mask = 0xffffffffUL;	/* PARISC devices are 32-bit */
414 
415 	/* make the generic dma mask a pointer to the parisc one */
416 	dev->dev.dma_mask = &dev->dma_mask;
417 	dev->dev.coherent_dma_mask = dev->dma_mask;
418 	if (device_register(&dev->dev)) {
419 		kfree(dev);
420 		return NULL;
421 	}
422 
423 	return dev;
424 }
425 
426 struct match_id_data {
427 	char id;
428 	struct parisc_device * dev;
429 };
430 
431 static int match_by_id(struct device * dev, void * data)
432 {
433 	struct parisc_device * pdev = to_parisc_device(dev);
434 	struct match_id_data * d = data;
435 
436 	if (pdev->hw_path == d->id) {
437 		d->dev = pdev;
438 		return 1;
439 	}
440 	return 0;
441 }
442 
443 /**
444  * alloc_tree_node - returns a device entry in the iotree
445  * @parent: the parent node in the tree
446  * @id: the element of the module path for this entry
447  *
448  * Checks all the children of @parent for a matching @id.  If none
449  * found, it allocates a new device and returns it.
450  */
451 static struct parisc_device * __init alloc_tree_node(
452 			struct device *parent, char id)
453 {
454 	struct match_id_data d = {
455 		.id = id,
456 	};
457 	if (device_for_each_child(parent, &d, match_by_id))
458 		return d.dev;
459 	else
460 		return create_tree_node(id, parent);
461 }
462 
463 static struct parisc_device *create_parisc_device(struct hardware_path *modpath)
464 {
465 	int i;
466 	struct device *parent = &root;
467 	for (i = 0; i < 6; i++) {
468 		if (modpath->bc[i] == -1)
469 			continue;
470 		parent = &alloc_tree_node(parent, modpath->bc[i])->dev;
471 	}
472 	return alloc_tree_node(parent, modpath->mod);
473 }
474 
475 struct parisc_device * __init
476 alloc_pa_dev(unsigned long hpa, struct hardware_path *mod_path)
477 {
478 	int status;
479 	unsigned long bytecnt;
480 	u8 iodc_data[32];
481 	struct parisc_device *dev;
482 	const char *name;
483 
484 	/* Check to make sure this device has not already been added - Ryan */
485 	if (find_device_by_addr(hpa) != NULL)
486 		return NULL;
487 
488 	status = pdc_iodc_read(&bytecnt, hpa, 0, &iodc_data, 32);
489 	if (status != PDC_OK)
490 		return NULL;
491 
492 	dev = create_parisc_device(mod_path);
493 	if (dev->id.hw_type != HPHW_FAULTY) {
494 		printk(KERN_ERR "Two devices have hardware path [%s].  "
495 				"IODC data for second device: "
496 				"%02x%02x%02x%02x%02x%02x\n"
497 				"Rearranging GSC cards sometimes helps\n",
498 			parisc_pathname(dev), iodc_data[0], iodc_data[1],
499 			iodc_data[3], iodc_data[4], iodc_data[5], iodc_data[6]);
500 		return NULL;
501 	}
502 
503 	dev->id.hw_type = iodc_data[3] & 0x1f;
504 	dev->id.hversion = (iodc_data[0] << 4) | ((iodc_data[1] & 0xf0) >> 4);
505 	dev->id.hversion_rev = iodc_data[1] & 0x0f;
506 	dev->id.sversion = ((iodc_data[4] & 0x0f) << 16) |
507 			(iodc_data[5] << 8) | iodc_data[6];
508 	dev->hpa.name = parisc_pathname(dev);
509 	dev->hpa.start = hpa;
510 	/* This is awkward.  The STI spec says that gfx devices may occupy
511 	 * 32MB or 64MB.  Unfortunately, we don't know how to tell whether
512 	 * it's the former or the latter.  Assumptions either way can hurt us.
513 	 */
514 	if (hpa == 0xf4000000 || hpa == 0xf8000000) {
515 		dev->hpa.end = hpa + 0x03ffffff;
516 	} else if (hpa == 0xf6000000 || hpa == 0xfa000000) {
517 		dev->hpa.end = hpa + 0x01ffffff;
518 	} else {
519 		dev->hpa.end = hpa + 0xfff;
520 	}
521 	dev->hpa.flags = IORESOURCE_MEM;
522 	name = parisc_hardware_description(&dev->id);
523 	if (name) {
524 		strlcpy(dev->name, name, sizeof(dev->name));
525 	}
526 
527 	/* Silently fail things like mouse ports which are subsumed within
528 	 * the keyboard controller
529 	 */
530 	if ((hpa & 0xfff) == 0 && insert_resource(&iomem_resource, &dev->hpa))
531 		printk("Unable to claim HPA %lx for device %s\n",
532 				hpa, name);
533 
534 	return dev;
535 }
536 
537 static int parisc_generic_match(struct device *dev, struct device_driver *drv)
538 {
539 	return match_device(to_parisc_driver(drv), to_parisc_device(dev));
540 }
541 
542 static ssize_t make_modalias(struct device *dev, char *buf)
543 {
544 	const struct parisc_device *padev = to_parisc_device(dev);
545 	const struct parisc_device_id *id = &padev->id;
546 
547 	return sprintf(buf, "parisc:t%02Xhv%04Xrev%02Xsv%08X\n",
548 		(u8)id->hw_type, (u16)id->hversion, (u8)id->hversion_rev,
549 		(u32)id->sversion);
550 }
551 
552 static int parisc_uevent(struct device *dev, struct kobj_uevent_env *env)
553 {
554 	const struct parisc_device *padev;
555 	char modalias[40];
556 
557 	if (!dev)
558 		return -ENODEV;
559 
560 	padev = to_parisc_device(dev);
561 	if (!padev)
562 		return -ENODEV;
563 
564 	if (add_uevent_var(env, "PARISC_NAME=%s", padev->name))
565 		return -ENOMEM;
566 
567 	make_modalias(dev, modalias);
568 	if (add_uevent_var(env, "MODALIAS=%s", modalias))
569 		return -ENOMEM;
570 
571 	return 0;
572 }
573 
574 #define pa_dev_attr(name, field, format_string)				\
575 static ssize_t name##_show(struct device *dev, struct device_attribute *attr, char *buf)		\
576 {									\
577 	struct parisc_device *padev = to_parisc_device(dev);		\
578 	return sprintf(buf, format_string, padev->field);		\
579 }									\
580 static DEVICE_ATTR_RO(name);
581 
582 #define pa_dev_attr_id(field, format) pa_dev_attr(field, id.field, format)
583 
584 pa_dev_attr(irq, irq, "%u\n");
585 pa_dev_attr_id(hw_type, "0x%02x\n");
586 pa_dev_attr(rev, id.hversion_rev, "0x%x\n");
587 pa_dev_attr_id(hversion, "0x%03x\n");
588 pa_dev_attr_id(sversion, "0x%05x\n");
589 
590 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf)
591 {
592 	return make_modalias(dev, buf);
593 }
594 static DEVICE_ATTR_RO(modalias);
595 
596 static struct attribute *parisc_device_attrs[] = {
597 	&dev_attr_irq.attr,
598 	&dev_attr_hw_type.attr,
599 	&dev_attr_rev.attr,
600 	&dev_attr_hversion.attr,
601 	&dev_attr_sversion.attr,
602 	&dev_attr_modalias.attr,
603 	NULL,
604 };
605 ATTRIBUTE_GROUPS(parisc_device);
606 
607 struct bus_type parisc_bus_type = {
608 	.name = "parisc",
609 	.match = parisc_generic_match,
610 	.uevent = parisc_uevent,
611 	.dev_groups = parisc_device_groups,
612 	.probe = parisc_driver_probe,
613 	.remove = __exit_p(parisc_driver_remove),
614 };
615 
616 /**
617  * register_parisc_device - Locate a driver to manage this device.
618  * @dev: The parisc device.
619  *
620  * Search the driver list for a driver that is willing to manage
621  * this device.
622  */
623 int __init register_parisc_device(struct parisc_device *dev)
624 {
625 	if (!dev)
626 		return 0;
627 
628 	if (dev->driver)
629 		return 1;
630 
631 	return 0;
632 }
633 
634 /**
635  * match_pci_device - Matches a pci device against a given hardware path
636  * entry.
637  * @dev: the generic device (known to be contained by a pci_dev).
638  * @index: the current BC index
639  * @modpath: the hardware path.
640  * @return: true if the device matches the hardware path.
641  */
642 static int match_pci_device(struct device *dev, int index,
643 		struct hardware_path *modpath)
644 {
645 	struct pci_dev *pdev = to_pci_dev(dev);
646 	int id;
647 
648 	if (index == 5) {
649 		/* we are at the end of the path, and on the actual device */
650 		unsigned int devfn = pdev->devfn;
651 		return ((modpath->bc[5] == PCI_SLOT(devfn)) &&
652 					(modpath->mod == PCI_FUNC(devfn)));
653 	}
654 
655 	/* index might be out of bounds for bc[] */
656 	if (index >= 6)
657 		return 0;
658 
659 	id = PCI_SLOT(pdev->devfn) | (PCI_FUNC(pdev->devfn) << 5);
660 	return (modpath->bc[index] == id);
661 }
662 
663 /**
664  * match_parisc_device - Matches a parisc device against a given hardware
665  * path entry.
666  * @dev: the generic device (known to be contained by a parisc_device).
667  * @index: the current BC index
668  * @modpath: the hardware path.
669  * @return: true if the device matches the hardware path.
670  */
671 static int match_parisc_device(struct device *dev, int index,
672 		struct hardware_path *modpath)
673 {
674 	struct parisc_device *curr = to_parisc_device(dev);
675 	char id = (index == 6) ? modpath->mod : modpath->bc[index];
676 
677 	return (curr->hw_path == id);
678 }
679 
680 struct parse_tree_data {
681 	int index;
682 	struct hardware_path * modpath;
683 	struct device * dev;
684 };
685 
686 static int check_parent(struct device * dev, void * data)
687 {
688 	struct parse_tree_data * d = data;
689 
690 	if (check_dev(dev)) {
691 		if (dev->bus == &parisc_bus_type) {
692 			if (match_parisc_device(dev, d->index, d->modpath))
693 				d->dev = dev;
694 		} else if (dev_is_pci(dev)) {
695 			if (match_pci_device(dev, d->index, d->modpath))
696 				d->dev = dev;
697 		} else if (dev->bus == NULL) {
698 			/* we are on a bus bridge */
699 			struct device *new = parse_tree_node(dev, d->index, d->modpath);
700 			if (new)
701 				d->dev = new;
702 		}
703 	}
704 	return d->dev != NULL;
705 }
706 
707 /**
708  * parse_tree_node - returns a device entry in the iotree
709  * @parent: the parent node in the tree
710  * @index: the current BC index
711  * @modpath: the hardware_path struct to match a device against
712  * @return: The corresponding device if found, NULL otherwise.
713  *
714  * Checks all the children of @parent for a matching @id.  If none
715  * found, it returns NULL.
716  */
717 static struct device *
718 parse_tree_node(struct device *parent, int index, struct hardware_path *modpath)
719 {
720 	struct parse_tree_data d = {
721 		.index          = index,
722 		.modpath        = modpath,
723 	};
724 
725 	struct recurse_struct recurse_data = {
726 		.obj	= &d,
727 		.fn	= check_parent,
728 	};
729 
730 	if (device_for_each_child(parent, &recurse_data, descend_children))
731 		/* nothing */;
732 
733 	return d.dev;
734 }
735 
736 /**
737  * hwpath_to_device - Finds the generic device corresponding to a given hardware path.
738  * @modpath: the hardware path.
739  * @return: The target device, NULL if not found.
740  */
741 struct device *hwpath_to_device(struct hardware_path *modpath)
742 {
743 	int i;
744 	struct device *parent = &root;
745 	for (i = 0; i < 6; i++) {
746 		if (modpath->bc[i] == -1)
747 			continue;
748 		parent = parse_tree_node(parent, i, modpath);
749 		if (!parent)
750 			return NULL;
751 	}
752 	if (dev_is_pci(parent)) /* pci devices already parse MOD */
753 		return parent;
754 	else
755 		return parse_tree_node(parent, 6, modpath);
756 }
757 EXPORT_SYMBOL(hwpath_to_device);
758 
759 /**
760  * device_to_hwpath - Populates the hwpath corresponding to the given device.
761  * @param dev the target device
762  * @param path pointer to a previously allocated hwpath struct to be filled in
763  */
764 void device_to_hwpath(struct device *dev, struct hardware_path *path)
765 {
766 	struct parisc_device *padev;
767 	if (dev->bus == &parisc_bus_type) {
768 		padev = to_parisc_device(dev);
769 		get_node_path(dev->parent, path);
770 		path->mod = padev->hw_path;
771 	} else if (dev_is_pci(dev)) {
772 		get_node_path(dev, path);
773 	}
774 }
775 EXPORT_SYMBOL(device_to_hwpath);
776 
777 #define BC_PORT_MASK 0x8
778 #define BC_LOWER_PORT 0x8
779 
780 #define BUS_CONVERTER(dev) \
781         ((dev->id.hw_type == HPHW_IOA) || (dev->id.hw_type == HPHW_BCPORT))
782 
783 #define IS_LOWER_PORT(dev) \
784         ((gsc_readl(dev->hpa.start + offsetof(struct bc_module, io_status)) \
785                 & BC_PORT_MASK) == BC_LOWER_PORT)
786 
787 #define MAX_NATIVE_DEVICES 64
788 #define NATIVE_DEVICE_OFFSET 0x1000
789 
790 #define FLEX_MASK 	F_EXTEND(0xfffc0000)
791 #define IO_IO_LOW	offsetof(struct bc_module, io_io_low)
792 #define IO_IO_HIGH	offsetof(struct bc_module, io_io_high)
793 #define READ_IO_IO_LOW(dev)  (unsigned long)(signed int)gsc_readl(dev->hpa.start + IO_IO_LOW)
794 #define READ_IO_IO_HIGH(dev) (unsigned long)(signed int)gsc_readl(dev->hpa.start + IO_IO_HIGH)
795 
796 static void walk_native_bus(unsigned long io_io_low, unsigned long io_io_high,
797                             struct device *parent);
798 
799 static void walk_lower_bus(struct parisc_device *dev)
800 {
801 	unsigned long io_io_low, io_io_high;
802 
803 	if (!BUS_CONVERTER(dev) || IS_LOWER_PORT(dev))
804 		return;
805 
806 	if (dev->id.hw_type == HPHW_IOA) {
807 		io_io_low = (unsigned long)(signed int)(READ_IO_IO_LOW(dev) << 16);
808 		io_io_high = io_io_low + MAX_NATIVE_DEVICES * NATIVE_DEVICE_OFFSET;
809 	} else {
810 		io_io_low = (READ_IO_IO_LOW(dev) + ~FLEX_MASK) & FLEX_MASK;
811 		io_io_high = (READ_IO_IO_HIGH(dev)+ ~FLEX_MASK) & FLEX_MASK;
812 	}
813 
814 	walk_native_bus(io_io_low, io_io_high, &dev->dev);
815 }
816 
817 /**
818  * walk_native_bus -- Probe a bus for devices
819  * @io_io_low: Base address of this bus.
820  * @io_io_high: Last address of this bus.
821  * @parent: The parent bus device.
822  *
823  * A native bus (eg Runway or GSC) may have up to 64 devices on it,
824  * spaced at intervals of 0x1000 bytes.  PDC may not inform us of these
825  * devices, so we have to probe for them.  Unfortunately, we may find
826  * devices which are not physically connected (such as extra serial &
827  * keyboard ports).  This problem is not yet solved.
828  */
829 static void __init walk_native_bus(unsigned long io_io_low,
830 	unsigned long io_io_high, struct device *parent)
831 {
832 	int i, devices_found = 0;
833 	unsigned long hpa = io_io_low;
834 	struct hardware_path path;
835 
836 	get_node_path(parent, &path);
837 	do {
838 		for(i = 0; i < MAX_NATIVE_DEVICES; i++, hpa += NATIVE_DEVICE_OFFSET) {
839 			struct parisc_device *dev;
840 
841 			/* Was the device already added by Firmware? */
842 			dev = find_device_by_addr(hpa);
843 			if (!dev) {
844 				path.mod = i;
845 				dev = alloc_pa_dev(hpa, &path);
846 				if (!dev)
847 					continue;
848 
849 				register_parisc_device(dev);
850 				devices_found++;
851 			}
852 			walk_lower_bus(dev);
853 		}
854 	} while(!devices_found && hpa < io_io_high);
855 }
856 
857 #define CENTRAL_BUS_ADDR F_EXTEND(0xfff80000)
858 
859 /**
860  * walk_central_bus - Find devices attached to the central bus
861  *
862  * PDC doesn't tell us about all devices in the system.  This routine
863  * finds devices connected to the central bus.
864  */
865 void __init walk_central_bus(void)
866 {
867 	walk_native_bus(CENTRAL_BUS_ADDR,
868 			CENTRAL_BUS_ADDR + (MAX_NATIVE_DEVICES * NATIVE_DEVICE_OFFSET),
869 			&root);
870 }
871 
872 static void print_parisc_device(struct parisc_device *dev)
873 {
874 	char hw_path[64];
875 	static int count;
876 
877 	print_pa_hwpath(dev, hw_path);
878 	printk(KERN_INFO "%d. %s at 0x%px [%s] { %d, 0x%x, 0x%.3x, 0x%.5x }",
879 		++count, dev->name, (void*) dev->hpa.start, hw_path, dev->id.hw_type,
880 		dev->id.hversion_rev, dev->id.hversion, dev->id.sversion);
881 
882 	if (dev->num_addrs) {
883 		int k;
884 		pr_cont(", additional addresses: ");
885 		for (k = 0; k < dev->num_addrs; k++)
886 			pr_cont("0x%lx ", dev->addr[k]);
887 	}
888 	pr_cont("\n");
889 }
890 
891 /**
892  * init_parisc_bus - Some preparation to be done before inventory
893  */
894 void __init init_parisc_bus(void)
895 {
896 	if (bus_register(&parisc_bus_type))
897 		panic("Could not register PA-RISC bus type\n");
898 	if (device_register(&root))
899 		panic("Could not register PA-RISC root device\n");
900 	get_device(&root);
901 }
902 
903 static __init void qemu_header(void)
904 {
905 	int num;
906 	unsigned long *p;
907 
908 	pr_info("--- cut here ---\n");
909 	pr_info("/* AUTO-GENERATED HEADER FILE FOR SEABIOS FIRMWARE */\n");
910 	pr_cont("/* generated with Linux kernel */\n");
911 	pr_cont("/* search for PARISC_QEMU_MACHINE_HEADER in Linux */\n\n");
912 
913 	pr_info("#define PARISC_MODEL \"%s\"\n\n",
914 			boot_cpu_data.pdc.sys_model_name);
915 
916 	pr_info("#define PARISC_PDC_MODEL 0x%lx, 0x%lx, 0x%lx, "
917 		"0x%lx, 0x%lx, 0x%lx, 0x%lx, 0x%lx, 0x%lx\n\n",
918 	#define p ((unsigned long *)&boot_cpu_data.pdc.model)
919 		p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8]);
920 	#undef p
921 
922 	pr_info("#define PARISC_PDC_VERSION 0x%04lx\n\n",
923 			boot_cpu_data.pdc.versions);
924 
925 	pr_info("#define PARISC_PDC_CPUID 0x%04lx\n\n",
926 			boot_cpu_data.pdc.cpuid);
927 
928 	pr_info("#define PARISC_PDC_CAPABILITIES 0x%04lx\n\n",
929 			boot_cpu_data.pdc.capabilities);
930 
931 	pr_info("#define PARISC_PDC_ENTRY_ORG 0x%04lx\n\n",
932 #ifdef CONFIG_64BIT
933 		(unsigned long)(PAGE0->mem_pdc_hi) << 32 |
934 #endif
935 		(unsigned long)PAGE0->mem_pdc);
936 
937 	pr_info("#define PARISC_PDC_CACHE_INFO");
938 	p = (unsigned long *) &cache_info;
939 	for (num = 0; num < sizeof(cache_info); num += sizeof(unsigned long)) {
940 		if (((num % 5) == 0)) {
941 			pr_cont(" \\\n");
942 			pr_info("\t");
943 		}
944 		pr_cont("%s0x%04lx",
945 			num?", ":"", *p++);
946 	}
947 	pr_cont("\n\n");
948 }
949 
950 static __init int qemu_print_hpa(struct device *lin_dev, void *data)
951 {
952 	struct parisc_device *dev = to_parisc_device(lin_dev);
953 	unsigned long hpa = dev->hpa.start;
954 
955 	pr_cont("\t{\t.hpa = 0x%08lx,\\\n", hpa);
956 	pr_cont("\t\t.iodc = &iodc_data_hpa_%08lx,\\\n", hpa);
957 	pr_cont("\t\t.mod_info = &mod_info_hpa_%08lx,\\\n", hpa);
958 	pr_cont("\t\t.mod_path = &mod_path_hpa_%08lx,\\\n", hpa);
959 	pr_cont("\t\t.num_addr = HPA_%08lx_num_addr,\\\n", hpa);
960 	pr_cont("\t\t.add_addr = { HPA_%08lx_add_addr } },\\\n", hpa);
961 	return 0;
962 }
963 
964 
965 static __init void qemu_footer(void)
966 {
967 	pr_info("\n\n#define PARISC_DEVICE_LIST \\\n");
968 	for_each_padev(qemu_print_hpa, NULL);
969 	pr_cont("\t{ 0, }\n");
970 	pr_info("--- cut here ---\n");
971 }
972 
973 /* print iodc data of the various hpa modules for qemu inclusion */
974 static __init int qemu_print_iodc_data(struct device *lin_dev, void *data)
975 {
976 	struct parisc_device *dev = to_parisc_device(lin_dev);
977 	unsigned long count;
978 	unsigned long hpa = dev->hpa.start;
979 	int status;
980 	struct pdc_iodc iodc_data;
981 
982 	int mod_index;
983 	struct pdc_system_map_mod_info pdc_mod_info;
984 	struct pdc_module_path mod_path;
985 
986 	status = pdc_iodc_read(&count, hpa, 0,
987 		&iodc_data, sizeof(iodc_data));
988 	if (status != PDC_OK) {
989 		pr_info("No IODC data for hpa 0x%08lx\n", hpa);
990 		return 0;
991 	}
992 
993 	pr_info("\n");
994 
995 	pr_info("#define HPA_%08lx_DESCRIPTION \"%s\"\n",
996 		hpa, parisc_hardware_description(&dev->id));
997 
998 	mod_index = 0;
999 	do {
1000 		status = pdc_system_map_find_mods(&pdc_mod_info,
1001 				&mod_path, mod_index++);
1002 	} while (status == PDC_OK && pdc_mod_info.mod_addr != hpa);
1003 
1004 	pr_info("static struct pdc_system_map_mod_info"
1005 		" mod_info_hpa_%08lx = {\n", hpa);
1006 	#define DO(member) \
1007 		pr_cont("\t." #member " = 0x%x,\n", \
1008 			(unsigned int)pdc_mod_info.member)
1009 	DO(mod_addr);
1010 	DO(mod_pgs);
1011 	DO(add_addrs);
1012 	pr_cont("};\n");
1013 	#undef DO
1014 	pr_info("static struct pdc_module_path "
1015 		"mod_path_hpa_%08lx = {\n", hpa);
1016 	pr_cont("\t.path = { ");
1017 	pr_cont(".flags = 0x%x, ", mod_path.path.flags);
1018 	pr_cont(".bc = { 0x%x, 0x%x, 0x%x, 0x%x, 0x%x, 0x%x }, ",
1019 		(unsigned char)mod_path.path.bc[0],
1020 		(unsigned char)mod_path.path.bc[1],
1021 		(unsigned char)mod_path.path.bc[2],
1022 		(unsigned char)mod_path.path.bc[3],
1023 		(unsigned char)mod_path.path.bc[4],
1024 		(unsigned char)mod_path.path.bc[5]);
1025 	pr_cont(".mod = 0x%x ", mod_path.path.mod);
1026 	pr_cont(" },\n");
1027 	pr_cont("\t.layers = { 0x%x, 0x%x, 0x%x, 0x%x, 0x%x, 0x%x }\n",
1028 		mod_path.layers[0], mod_path.layers[1], mod_path.layers[2],
1029 		mod_path.layers[3], mod_path.layers[4], mod_path.layers[5]);
1030 	pr_cont("};\n");
1031 
1032 	pr_info("static struct pdc_iodc iodc_data_hpa_%08lx = {\n", hpa);
1033 	#define DO(member) \
1034 		pr_cont("\t." #member " = 0x%04lx,\n", \
1035 			(unsigned long)iodc_data.member)
1036 	DO(hversion_model);
1037 	DO(hversion);
1038 	DO(spa);
1039 	DO(type);
1040 	DO(sversion_rev);
1041 	DO(sversion_model);
1042 	DO(sversion_opt);
1043 	DO(rev);
1044 	DO(dep);
1045 	DO(features);
1046 	DO(checksum);
1047 	DO(length);
1048 	#undef DO
1049 	pr_cont("\t/* pad: 0x%04x, 0x%04x */\n",
1050 		iodc_data.pad[0], iodc_data.pad[1]);
1051 	pr_cont("};\n");
1052 
1053 	pr_info("#define HPA_%08lx_num_addr %d\n", hpa, dev->num_addrs);
1054 	pr_info("#define HPA_%08lx_add_addr ", hpa);
1055 	count = 0;
1056 	if (dev->num_addrs == 0)
1057 		pr_cont("0");
1058 	while (count < dev->num_addrs) {
1059 		pr_cont("0x%08lx, ", dev->addr[count]);
1060 		count++;
1061 	}
1062 	pr_cont("\n\n");
1063 
1064 	return 0;
1065 }
1066 
1067 
1068 
1069 static int print_one_device(struct device * dev, void * data)
1070 {
1071 	struct parisc_device * pdev = to_parisc_device(dev);
1072 
1073 	if (check_dev(dev))
1074 		print_parisc_device(pdev);
1075 	return 0;
1076 }
1077 
1078 /**
1079  * print_parisc_devices - Print out a list of devices found in this system
1080  */
1081 void __init print_parisc_devices(void)
1082 {
1083 	for_each_padev(print_one_device, NULL);
1084 	#define PARISC_QEMU_MACHINE_HEADER 0
1085 	if (PARISC_QEMU_MACHINE_HEADER) {
1086 		qemu_header();
1087 		for_each_padev(qemu_print_iodc_data, NULL);
1088 		qemu_footer();
1089 	}
1090 }
1091