xref: /linux/arch/parisc/kernel/drivers.c (revision 858259cf7d1c443c836a2022b78cb281f0a9b95e)
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 <asm/hardware.h>
37 #include <asm/io.h>
38 #include <asm/pdc.h>
39 #include <asm/parisc-device.h>
40 
41 /* See comments in include/asm-parisc/pci.h */
42 struct hppa_dma_ops *hppa_dma_ops;
43 EXPORT_SYMBOL(hppa_dma_ops);
44 
45 static struct device root = {
46 	.bus_id = "parisc",
47 };
48 
49 static inline int check_dev(struct device *dev)
50 {
51 	if (dev->bus == &parisc_bus_type) {
52 		struct parisc_device *pdev;
53 		pdev = to_parisc_device(dev);
54 		return pdev->id.hw_type != HPHW_FAULTY;
55 	}
56 	return 1;
57 }
58 
59 static struct device *
60 parse_tree_node(struct device *parent, int index, struct hardware_path *modpath);
61 
62 struct recurse_struct {
63 	void * obj;
64 	int (*fn)(struct device *, void *);
65 };
66 
67 static int descend_children(struct device * dev, void * data)
68 {
69 	struct recurse_struct * recurse_data = (struct recurse_struct *)data;
70 
71 	if (recurse_data->fn(dev, recurse_data->obj))
72 		return 1;
73 	else
74 		return device_for_each_child(dev, recurse_data, descend_children);
75 }
76 
77 /**
78  *	for_each_padev - Iterate over all devices in the tree
79  *	@fn:	Function to call for each device.
80  *	@data:	Data to pass to the called function.
81  *
82  *	This performs a depth-first traversal of the tree, calling the
83  *	function passed for each node.  It calls the function for parents
84  *	before children.
85  */
86 
87 static int for_each_padev(int (*fn)(struct device *, void *), void * data)
88 {
89 	struct recurse_struct recurse_data = {
90 		.obj	= data,
91 		.fn	= fn,
92 	};
93 	return device_for_each_child(&root, &recurse_data, descend_children);
94 }
95 
96 /**
97  * match_device - Report whether this driver can handle this device
98  * @driver: the PA-RISC driver to try
99  * @dev: the PA-RISC device to try
100  */
101 static int match_device(struct parisc_driver *driver, struct parisc_device *dev)
102 {
103 	const struct parisc_device_id *ids;
104 
105 	for (ids = driver->id_table; ids->sversion; ids++) {
106 		if ((ids->sversion != SVERSION_ANY_ID) &&
107 		    (ids->sversion != dev->id.sversion))
108 			continue;
109 
110 		if ((ids->hw_type != HWTYPE_ANY_ID) &&
111 		    (ids->hw_type != dev->id.hw_type))
112 			continue;
113 
114 		if ((ids->hversion != HVERSION_ANY_ID) &&
115 		    (ids->hversion != dev->id.hversion))
116 			continue;
117 
118 		return 1;
119 	}
120 	return 0;
121 }
122 
123 static int parisc_driver_probe(struct device *dev)
124 {
125 	int rc;
126 	struct parisc_device *pa_dev = to_parisc_device(dev);
127 	struct parisc_driver *pa_drv = to_parisc_driver(dev->driver);
128 
129 	rc = pa_drv->probe(pa_dev);
130 
131 	if (!rc)
132 		pa_dev->driver = pa_drv;
133 
134 	return rc;
135 }
136 
137 static int parisc_driver_remove(struct device *dev)
138 {
139 	struct parisc_device *pa_dev = to_parisc_device(dev);
140 	struct parisc_driver *pa_drv = to_parisc_driver(dev->driver);
141 	if (pa_drv->remove)
142 		pa_drv->remove(pa_dev);
143 
144 	return 0;
145 }
146 
147 
148 /**
149  * register_parisc_driver - Register this driver if it can handle a device
150  * @driver: the PA-RISC driver to try
151  */
152 int register_parisc_driver(struct parisc_driver *driver)
153 {
154 	/* FIXME: we need this because apparently the sti
155 	 * driver can be registered twice */
156 	if(driver->drv.name) {
157 		printk(KERN_WARNING
158 		       "BUG: skipping previously registered driver %s\n",
159 		       driver->name);
160 		return 1;
161 	}
162 
163 	if (!driver->probe) {
164 		printk(KERN_WARNING
165 		       "BUG: driver %s has no probe routine\n",
166 		       driver->name);
167 		return 1;
168 	}
169 
170 	driver->drv.bus = &parisc_bus_type;
171 
172 	/* We install our own probe and remove routines */
173 	WARN_ON(driver->drv.probe != NULL);
174 	WARN_ON(driver->drv.remove != NULL);
175 
176 	driver->drv.probe = parisc_driver_probe;
177 	driver->drv.remove = parisc_driver_remove;
178 	driver->drv.name = driver->name;
179 
180 	return driver_register(&driver->drv);
181 }
182 EXPORT_SYMBOL(register_parisc_driver);
183 
184 
185 struct match_count {
186 	struct parisc_driver * driver;
187 	int count;
188 };
189 
190 static int match_and_count(struct device * dev, void * data)
191 {
192 	struct match_count * m = data;
193 	struct parisc_device * pdev = to_parisc_device(dev);
194 
195 	if (check_dev(dev)) {
196 		if (match_device(m->driver, pdev))
197 			m->count++;
198 	}
199 	return 0;
200 }
201 
202 /**
203  * count_parisc_driver - count # of devices this driver would match
204  * @driver: the PA-RISC driver to try
205  *
206  * Use by IOMMU support to "guess" the right size IOPdir.
207  * Formula is something like memsize/(num_iommu * entry_size).
208  */
209 int count_parisc_driver(struct parisc_driver *driver)
210 {
211 	struct match_count m = {
212 		.driver	= driver,
213 		.count	= 0,
214 	};
215 
216 	for_each_padev(match_and_count, &m);
217 
218 	return m.count;
219 }
220 
221 
222 
223 /**
224  * unregister_parisc_driver - Unregister this driver from the list of drivers
225  * @driver: the PA-RISC driver to unregister
226  */
227 int unregister_parisc_driver(struct parisc_driver *driver)
228 {
229 	driver_unregister(&driver->drv);
230 	return 0;
231 }
232 EXPORT_SYMBOL(unregister_parisc_driver);
233 
234 struct find_data {
235 	unsigned long hpa;
236 	struct parisc_device * dev;
237 };
238 
239 static int find_device(struct device * dev, void * data)
240 {
241 	struct parisc_device * pdev = to_parisc_device(dev);
242 	struct find_data * d = (struct find_data*)data;
243 
244 	if (check_dev(dev)) {
245 		if (pdev->hpa.start == d->hpa) {
246 			d->dev = pdev;
247 			return 1;
248 		}
249 	}
250 	return 0;
251 }
252 
253 static struct parisc_device *find_device_by_addr(unsigned long hpa)
254 {
255 	struct find_data d = {
256 		.hpa	= hpa,
257 	};
258 	int ret;
259 
260 	ret = for_each_padev(find_device, &d);
261 	return ret ? d.dev : NULL;
262 }
263 
264 /**
265  * find_pa_parent_type - Find a parent of a specific type
266  * @dev: The device to start searching from
267  * @type: The device type to search for.
268  *
269  * Walks up the device tree looking for a device of the specified type.
270  * If it finds it, it returns it.  If not, it returns NULL.
271  */
272 const struct parisc_device *
273 find_pa_parent_type(const struct parisc_device *padev, int type)
274 {
275 	const struct device *dev = &padev->dev;
276 	while (dev != &root) {
277 		struct parisc_device *candidate = to_parisc_device(dev);
278 		if (candidate->id.hw_type == type)
279 			return candidate;
280 		dev = dev->parent;
281 	}
282 
283 	return NULL;
284 }
285 
286 #ifdef CONFIG_PCI
287 static inline int is_pci_dev(struct device *dev)
288 {
289 	return dev->bus == &pci_bus_type;
290 }
291 #else
292 static inline int is_pci_dev(struct device *dev)
293 {
294 	return 0;
295 }
296 #endif
297 
298 /*
299  * get_node_path fills in @path with the firmware path to the device.
300  * Note that if @node is a parisc device, we don't fill in the 'mod' field.
301  * This is because both callers pass the parent and fill in the mod
302  * themselves.  If @node is a PCI device, we do fill it in, even though this
303  * is inconsistent.
304  */
305 static void get_node_path(struct device *dev, struct hardware_path *path)
306 {
307 	int i = 5;
308 	memset(&path->bc, -1, 6);
309 
310 	if (is_pci_dev(dev)) {
311 		unsigned int devfn = to_pci_dev(dev)->devfn;
312 		path->mod = PCI_FUNC(devfn);
313 		path->bc[i--] = PCI_SLOT(devfn);
314 		dev = dev->parent;
315 	}
316 
317 	while (dev != &root) {
318 		if (is_pci_dev(dev)) {
319 			unsigned int devfn = to_pci_dev(dev)->devfn;
320 			path->bc[i--] = PCI_SLOT(devfn) | (PCI_FUNC(devfn)<< 5);
321 		} else if (dev->bus == &parisc_bus_type) {
322 			path->bc[i--] = to_parisc_device(dev)->hw_path;
323 		}
324 		dev = dev->parent;
325 	}
326 }
327 
328 static char *print_hwpath(struct hardware_path *path, char *output)
329 {
330 	int i;
331 	for (i = 0; i < 6; i++) {
332 		if (path->bc[i] == -1)
333 			continue;
334 		output += sprintf(output, "%u/", (unsigned char) path->bc[i]);
335 	}
336 	output += sprintf(output, "%u", (unsigned char) path->mod);
337 	return output;
338 }
339 
340 /**
341  * print_pa_hwpath - Returns hardware path for PA devices
342  * dev: The device to return the path for
343  * output: Pointer to a previously-allocated array to place the path in.
344  *
345  * This function fills in the output array with a human-readable path
346  * to a PA device.  This string is compatible with that used by PDC, and
347  * may be printed on the outside of the box.
348  */
349 char *print_pa_hwpath(struct parisc_device *dev, char *output)
350 {
351 	struct hardware_path path;
352 
353 	get_node_path(dev->dev.parent, &path);
354 	path.mod = dev->hw_path;
355 	return print_hwpath(&path, output);
356 }
357 EXPORT_SYMBOL(print_pa_hwpath);
358 
359 #if defined(CONFIG_PCI) || defined(CONFIG_ISA)
360 /**
361  * get_pci_node_path - Determines the hardware path for a PCI device
362  * @pdev: The device to return the path for
363  * @path: Pointer to a previously-allocated array to place the path in.
364  *
365  * This function fills in the hardware_path structure with the route to
366  * the specified PCI device.  This structure is suitable for passing to
367  * PDC calls.
368  */
369 void get_pci_node_path(struct pci_dev *pdev, struct hardware_path *path)
370 {
371 	get_node_path(&pdev->dev, path);
372 }
373 EXPORT_SYMBOL(get_pci_node_path);
374 
375 /**
376  * print_pci_hwpath - Returns hardware path for PCI devices
377  * dev: The device to return the path for
378  * output: Pointer to a previously-allocated array to place the path in.
379  *
380  * This function fills in the output array with a human-readable path
381  * to a PCI device.  This string is compatible with that used by PDC, and
382  * may be printed on the outside of the box.
383  */
384 char *print_pci_hwpath(struct pci_dev *dev, char *output)
385 {
386 	struct hardware_path path;
387 
388 	get_pci_node_path(dev, &path);
389 	return print_hwpath(&path, output);
390 }
391 EXPORT_SYMBOL(print_pci_hwpath);
392 
393 #endif /* defined(CONFIG_PCI) || defined(CONFIG_ISA) */
394 
395 static void setup_bus_id(struct parisc_device *padev)
396 {
397 	struct hardware_path path;
398 	char *output = padev->dev.bus_id;
399 	int i;
400 
401 	get_node_path(padev->dev.parent, &path);
402 
403 	for (i = 0; i < 6; i++) {
404 		if (path.bc[i] == -1)
405 			continue;
406 		output += sprintf(output, "%u:", (unsigned char) path.bc[i]);
407 	}
408 	sprintf(output, "%u", (unsigned char) padev->hw_path);
409 }
410 
411 struct parisc_device * create_tree_node(char id, struct device *parent)
412 {
413 	struct parisc_device *dev = kmalloc(sizeof(*dev), GFP_KERNEL);
414 	if (!dev)
415 		return NULL;
416 
417 	memset(dev, 0, sizeof(*dev));
418 	dev->hw_path = id;
419 	dev->id.hw_type = HPHW_FAULTY;
420 
421 	dev->dev.parent = parent;
422 	setup_bus_id(dev);
423 
424 	dev->dev.bus = &parisc_bus_type;
425 	dev->dma_mask = 0xffffffffUL;	/* PARISC devices are 32-bit */
426 
427 	/* make the generic dma mask a pointer to the parisc one */
428 	dev->dev.dma_mask = &dev->dma_mask;
429 	dev->dev.coherent_dma_mask = dev->dma_mask;
430 	device_register(&dev->dev);
431 
432 	return dev;
433 }
434 
435 struct match_id_data {
436 	char id;
437 	struct parisc_device * dev;
438 };
439 
440 static int match_by_id(struct device * dev, void * data)
441 {
442 	struct parisc_device * pdev = to_parisc_device(dev);
443 	struct match_id_data * d = data;
444 
445 	if (pdev->hw_path == d->id) {
446 		d->dev = pdev;
447 		return 1;
448 	}
449 	return 0;
450 }
451 
452 /**
453  * alloc_tree_node - returns a device entry in the iotree
454  * @parent: the parent node in the tree
455  * @id: the element of the module path for this entry
456  *
457  * Checks all the children of @parent for a matching @id.  If none
458  * found, it allocates a new device and returns it.
459  */
460 static struct parisc_device * alloc_tree_node(struct device *parent, char id)
461 {
462 	struct match_id_data d = {
463 		.id = id,
464 	};
465 	if (device_for_each_child(parent, &d, match_by_id))
466 		return d.dev;
467 	else
468 		return create_tree_node(id, parent);
469 }
470 
471 static struct parisc_device *create_parisc_device(struct hardware_path *modpath)
472 {
473 	int i;
474 	struct device *parent = &root;
475 	for (i = 0; i < 6; i++) {
476 		if (modpath->bc[i] == -1)
477 			continue;
478 		parent = &alloc_tree_node(parent, modpath->bc[i])->dev;
479 	}
480 	return alloc_tree_node(parent, modpath->mod);
481 }
482 
483 struct parisc_device *
484 alloc_pa_dev(unsigned long hpa, struct hardware_path *mod_path)
485 {
486 	int status;
487 	unsigned long bytecnt;
488 	u8 iodc_data[32];
489 	struct parisc_device *dev;
490 	const char *name;
491 
492 	/* Check to make sure this device has not already been added - Ryan */
493 	if (find_device_by_addr(hpa) != NULL)
494 		return NULL;
495 
496 	status = pdc_iodc_read(&bytecnt, hpa, 0, &iodc_data, 32);
497 	if (status != PDC_OK)
498 		return NULL;
499 
500 	dev = create_parisc_device(mod_path);
501 	if (dev->id.hw_type != HPHW_FAULTY) {
502 		printk("Two devices have hardware path %s.  Please file a bug with HP.\n"
503 			"In the meantime, you could try rearranging your cards.\n", parisc_pathname(dev));
504 		return NULL;
505 	}
506 
507 	dev->id.hw_type = iodc_data[3] & 0x1f;
508 	dev->id.hversion = (iodc_data[0] << 4) | ((iodc_data[1] & 0xf0) >> 4);
509 	dev->id.hversion_rev = iodc_data[1] & 0x0f;
510 	dev->id.sversion = ((iodc_data[4] & 0x0f) << 16) |
511 			(iodc_data[5] << 8) | iodc_data[6];
512 	dev->hpa.name = parisc_pathname(dev);
513 	dev->hpa.start = hpa;
514 	if (hpa == 0xf4000000 || hpa == 0xf6000000 ||
515 	    hpa == 0xf8000000 || hpa == 0xfa000000) {
516 		dev->hpa.end = hpa + 0x01ffffff;
517 	} else {
518 		dev->hpa.end = hpa + 0xfff;
519 	}
520 	dev->hpa.flags = IORESOURCE_MEM;
521 	name = parisc_hardware_description(&dev->id);
522 	if (name) {
523 		strlcpy(dev->name, name, sizeof(dev->name));
524 	}
525 
526 	/* Silently fail things like mouse ports which are subsumed within
527 	 * the keyboard controller
528 	 */
529 	if ((hpa & 0xfff) == 0 && insert_resource(&iomem_resource, &dev->hpa))
530 		printk("Unable to claim HPA %lx for device %s\n",
531 				hpa, name);
532 
533 	return dev;
534 }
535 
536 static int parisc_generic_match(struct device *dev, struct device_driver *drv)
537 {
538 	return match_device(to_parisc_driver(drv), to_parisc_device(dev));
539 }
540 
541 #define pa_dev_attr(name, field, format_string)				\
542 static ssize_t name##_show(struct device *dev, struct device_attribute *attr, char *buf)		\
543 {									\
544 	struct parisc_device *padev = to_parisc_device(dev);		\
545 	return sprintf(buf, format_string, padev->field);		\
546 }
547 
548 #define pa_dev_attr_id(field, format) pa_dev_attr(field, id.field, format)
549 
550 pa_dev_attr(irq, irq, "%u\n");
551 pa_dev_attr_id(hw_type, "0x%02x\n");
552 pa_dev_attr(rev, id.hversion_rev, "0x%x\n");
553 pa_dev_attr_id(hversion, "0x%03x\n");
554 pa_dev_attr_id(sversion, "0x%05x\n");
555 
556 static struct device_attribute parisc_device_attrs[] = {
557 	__ATTR_RO(irq),
558 	__ATTR_RO(hw_type),
559 	__ATTR_RO(rev),
560 	__ATTR_RO(hversion),
561 	__ATTR_RO(sversion),
562 	__ATTR_NULL,
563 };
564 
565 struct bus_type parisc_bus_type = {
566 	.name = "parisc",
567 	.match = parisc_generic_match,
568 	.dev_attrs = parisc_device_attrs,
569 };
570 
571 /**
572  * register_parisc_device - Locate a driver to manage this device.
573  * @dev: The parisc device.
574  *
575  * Search the driver list for a driver that is willing to manage
576  * this device.
577  */
578 int register_parisc_device(struct parisc_device *dev)
579 {
580 	if (!dev)
581 		return 0;
582 
583 	if (dev->driver)
584 		return 1;
585 
586 	return 0;
587 }
588 
589 /**
590  * match_pci_device - Matches a pci device against a given hardware path
591  * entry.
592  * @dev: the generic device (known to be contained by a pci_dev).
593  * @index: the current BC index
594  * @modpath: the hardware path.
595  * @return: true if the device matches the hardware path.
596  */
597 static int match_pci_device(struct device *dev, int index,
598 		struct hardware_path *modpath)
599 {
600 	struct pci_dev *pdev = to_pci_dev(dev);
601 	int id;
602 
603 	if (index == 5) {
604 		/* we are at the end of the path, and on the actual device */
605 		unsigned int devfn = pdev->devfn;
606 		return ((modpath->bc[5] == PCI_SLOT(devfn)) &&
607 					(modpath->mod == PCI_FUNC(devfn)));
608 	}
609 
610 	id = PCI_SLOT(pdev->devfn) | (PCI_FUNC(pdev->devfn) << 5);
611 	return (modpath->bc[index] == id);
612 }
613 
614 /**
615  * match_parisc_device - Matches a parisc device against a given hardware
616  * path entry.
617  * @dev: the generic device (known to be contained by a parisc_device).
618  * @index: the current BC index
619  * @modpath: the hardware path.
620  * @return: true if the device matches the hardware path.
621  */
622 static int match_parisc_device(struct device *dev, int index,
623 		struct hardware_path *modpath)
624 {
625 	struct parisc_device *curr = to_parisc_device(dev);
626 	char id = (index == 6) ? modpath->mod : modpath->bc[index];
627 
628 	return (curr->hw_path == id);
629 }
630 
631 struct parse_tree_data {
632 	int index;
633 	struct hardware_path * modpath;
634 	struct device * dev;
635 };
636 
637 static int check_parent(struct device * dev, void * data)
638 {
639 	struct parse_tree_data * d = data;
640 
641 	if (check_dev(dev)) {
642 		if (dev->bus == &parisc_bus_type) {
643 			if (match_parisc_device(dev, d->index, d->modpath))
644 				d->dev = dev;
645 		} else if (is_pci_dev(dev)) {
646 			if (match_pci_device(dev, d->index, d->modpath))
647 				d->dev = dev;
648 		} else if (dev->bus == NULL) {
649 			/* we are on a bus bridge */
650 			struct device *new = parse_tree_node(dev, d->index, d->modpath);
651 			if (new)
652 				d->dev = new;
653 		}
654 	}
655 	return d->dev != NULL;
656 }
657 
658 /**
659  * parse_tree_node - returns a device entry in the iotree
660  * @parent: the parent node in the tree
661  * @index: the current BC index
662  * @modpath: the hardware_path struct to match a device against
663  * @return: The corresponding device if found, NULL otherwise.
664  *
665  * Checks all the children of @parent for a matching @id.  If none
666  * found, it returns NULL.
667  */
668 static struct device *
669 parse_tree_node(struct device *parent, int index, struct hardware_path *modpath)
670 {
671 	struct parse_tree_data d = {
672 		.index          = index,
673 		.modpath        = modpath,
674 	};
675 
676 	struct recurse_struct recurse_data = {
677 		.obj	= &d,
678 		.fn	= check_parent,
679 	};
680 
681 	device_for_each_child(parent, &recurse_data, descend_children);
682 	return d.dev;
683 }
684 
685 /**
686  * hwpath_to_device - Finds the generic device corresponding to a given hardware path.
687  * @modpath: the hardware path.
688  * @return: The target device, NULL if not found.
689  */
690 struct device *hwpath_to_device(struct hardware_path *modpath)
691 {
692 	int i;
693 	struct device *parent = &root;
694 	for (i = 0; i < 6; i++) {
695 		if (modpath->bc[i] == -1)
696 			continue;
697 		parent = parse_tree_node(parent, i, modpath);
698 		if (!parent)
699 			return NULL;
700 	}
701 	if (is_pci_dev(parent)) /* pci devices already parse MOD */
702 		return parent;
703 	else
704 		return parse_tree_node(parent, 6, modpath);
705 }
706 EXPORT_SYMBOL(hwpath_to_device);
707 
708 /**
709  * device_to_hwpath - Populates the hwpath corresponding to the given device.
710  * @param dev the target device
711  * @param path pointer to a previously allocated hwpath struct to be filled in
712  */
713 void device_to_hwpath(struct device *dev, struct hardware_path *path)
714 {
715 	struct parisc_device *padev;
716 	if (dev->bus == &parisc_bus_type) {
717 		padev = to_parisc_device(dev);
718 		get_node_path(dev->parent, path);
719 		path->mod = padev->hw_path;
720 	} else if (is_pci_dev(dev)) {
721 		get_node_path(dev, path);
722 	}
723 }
724 EXPORT_SYMBOL(device_to_hwpath);
725 
726 #define BC_PORT_MASK 0x8
727 #define BC_LOWER_PORT 0x8
728 
729 #define BUS_CONVERTER(dev) \
730         ((dev->id.hw_type == HPHW_IOA) || (dev->id.hw_type == HPHW_BCPORT))
731 
732 #define IS_LOWER_PORT(dev) \
733         ((gsc_readl(dev->hpa.start + offsetof(struct bc_module, io_status)) \
734                 & BC_PORT_MASK) == BC_LOWER_PORT)
735 
736 #define MAX_NATIVE_DEVICES 64
737 #define NATIVE_DEVICE_OFFSET 0x1000
738 
739 #define FLEX_MASK 	F_EXTEND(0xfffc0000)
740 #define IO_IO_LOW	offsetof(struct bc_module, io_io_low)
741 #define IO_IO_HIGH	offsetof(struct bc_module, io_io_high)
742 #define READ_IO_IO_LOW(dev)  (unsigned long)(signed int)gsc_readl(dev->hpa.start + IO_IO_LOW)
743 #define READ_IO_IO_HIGH(dev) (unsigned long)(signed int)gsc_readl(dev->hpa.start + IO_IO_HIGH)
744 
745 static void walk_native_bus(unsigned long io_io_low, unsigned long io_io_high,
746                             struct device *parent);
747 
748 void walk_lower_bus(struct parisc_device *dev)
749 {
750 	unsigned long io_io_low, io_io_high;
751 
752 	if (!BUS_CONVERTER(dev) || IS_LOWER_PORT(dev))
753 		return;
754 
755 	if (dev->id.hw_type == HPHW_IOA) {
756 		io_io_low = (unsigned long)(signed int)(READ_IO_IO_LOW(dev) << 16);
757 		io_io_high = io_io_low + MAX_NATIVE_DEVICES * NATIVE_DEVICE_OFFSET;
758 	} else {
759 		io_io_low = (READ_IO_IO_LOW(dev) + ~FLEX_MASK) & FLEX_MASK;
760 		io_io_high = (READ_IO_IO_HIGH(dev)+ ~FLEX_MASK) & FLEX_MASK;
761 	}
762 
763 	walk_native_bus(io_io_low, io_io_high, &dev->dev);
764 }
765 
766 /**
767  * walk_native_bus -- Probe a bus for devices
768  * @io_io_low: Base address of this bus.
769  * @io_io_high: Last address of this bus.
770  * @parent: The parent bus device.
771  *
772  * A native bus (eg Runway or GSC) may have up to 64 devices on it,
773  * spaced at intervals of 0x1000 bytes.  PDC may not inform us of these
774  * devices, so we have to probe for them.  Unfortunately, we may find
775  * devices which are not physically connected (such as extra serial &
776  * keyboard ports).  This problem is not yet solved.
777  */
778 static void walk_native_bus(unsigned long io_io_low, unsigned long io_io_high,
779                             struct device *parent)
780 {
781 	int i, devices_found = 0;
782 	unsigned long hpa = io_io_low;
783 	struct hardware_path path;
784 
785 	get_node_path(parent, &path);
786 	do {
787 		for(i = 0; i < MAX_NATIVE_DEVICES; i++, hpa += NATIVE_DEVICE_OFFSET) {
788 			struct parisc_device *dev;
789 
790 			/* Was the device already added by Firmware? */
791 			dev = find_device_by_addr(hpa);
792 			if (!dev) {
793 				path.mod = i;
794 				dev = alloc_pa_dev(hpa, &path);
795 				if (!dev)
796 					continue;
797 
798 				register_parisc_device(dev);
799 				devices_found++;
800 			}
801 			walk_lower_bus(dev);
802 		}
803 	} while(!devices_found && hpa < io_io_high);
804 }
805 
806 #define CENTRAL_BUS_ADDR F_EXTEND(0xfff80000)
807 
808 /**
809  * walk_central_bus - Find devices attached to the central bus
810  *
811  * PDC doesn't tell us about all devices in the system.  This routine
812  * finds devices connected to the central bus.
813  */
814 void walk_central_bus(void)
815 {
816 	walk_native_bus(CENTRAL_BUS_ADDR,
817 			CENTRAL_BUS_ADDR + (MAX_NATIVE_DEVICES * NATIVE_DEVICE_OFFSET),
818 			&root);
819 }
820 
821 static void print_parisc_device(struct parisc_device *dev)
822 {
823 	char hw_path[64];
824 	static int count;
825 
826 	print_pa_hwpath(dev, hw_path);
827 	printk(KERN_INFO "%d. %s at 0x%lx [%s] { %d, 0x%x, 0x%.3x, 0x%.5x }",
828 		++count, dev->name, dev->hpa.start, hw_path, dev->id.hw_type,
829 		dev->id.hversion_rev, dev->id.hversion, dev->id.sversion);
830 
831 	if (dev->num_addrs) {
832 		int k;
833 		printk(",  additional addresses: ");
834 		for (k = 0; k < dev->num_addrs; k++)
835 			printk("0x%lx ", dev->addr[k]);
836 	}
837 	printk("\n");
838 }
839 
840 /**
841  * init_parisc_bus - Some preparation to be done before inventory
842  */
843 void init_parisc_bus(void)
844 {
845 	bus_register(&parisc_bus_type);
846 	device_register(&root);
847 	get_device(&root);
848 }
849 
850 
851 static int print_one_device(struct device * dev, void * data)
852 {
853 	struct parisc_device * pdev = to_parisc_device(dev);
854 
855 	if (check_dev(dev))
856 		print_parisc_device(pdev);
857 	return 0;
858 }
859 
860 /**
861  * print_parisc_devices - Print out a list of devices found in this system
862  */
863 void print_parisc_devices(void)
864 {
865 	for_each_padev(print_one_device, NULL);
866 }
867