xref: /openbmc/linux/arch/parisc/kernel/drivers.c (revision 2208f39c)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * drivers.c
4  *
5  * Copyright (c) 1999 The Puffin Group
6  * Copyright (c) 2001 Matthew Wilcox for Hewlett Packard
7  * Copyright (c) 2001 Helge Deller <deller@gmx.de>
8  * Copyright (c) 2001,2002 Ryan Bradetich
9  * Copyright (c) 2004-2005 Thibaut VARENE <varenet@parisc-linux.org>
10  *
11  * The file handles registering devices and drivers, then matching them.
12  * It's the closest we get to a dating agency.
13  *
14  * If you're thinking about modifying this file, here are some gotchas to
15  * bear in mind:
16  *  - 715/Mirage device paths have a dummy device between Lasi and its children
17  *  - The EISA adapter may show up as a sibling or child of Wax
18  *  - Dino has an optionally functional serial port.  If firmware enables it,
19  *    it shows up as a child of Dino.  If firmware disables it, the buswalk
20  *    finds it and it shows up as a child of Cujo
21  *  - Dino has both parisc and pci devices as children
22  *  - parisc devices are discovered in a random order, including children
23  *    before parents in some cases.
24  */
25 
26 #include <linux/slab.h>
27 #include <linux/types.h>
28 #include <linux/kernel.h>
29 #include <linux/pci.h>
30 #include <linux/spinlock.h>
31 #include <linux/string.h>
32 #include <linux/export.h>
33 #include <linux/dma-map-ops.h>
34 #include <asm/hardware.h>
35 #include <asm/io.h>
36 #include <asm/pdc.h>
37 #include <asm/parisc-device.h>
38 #include <asm/ropes.h>
39 
40 /* See comments in include/asm-parisc/pci.h */
41 const struct dma_map_ops *hppa_dma_ops __ro_after_init;
42 EXPORT_SYMBOL(hppa_dma_ops);
43 
44 static struct device root = {
45 	.init_name = "parisc",
46 };
47 
48 static inline int check_dev(struct device *dev)
49 {
50 	if (dev->bus == &parisc_bus_type) {
51 		struct parisc_device *pdev;
52 		pdev = to_parisc_device(dev);
53 		return pdev->id.hw_type != HPHW_FAULTY;
54 	}
55 	return 1;
56 }
57 
58 static struct device *
59 parse_tree_node(struct device *parent, int index, struct hardware_path *modpath);
60 
61 struct recurse_struct {
62 	void * obj;
63 	int (*fn)(struct device *, void *);
64 };
65 
66 static int descend_children(struct device * dev, void * data)
67 {
68 	struct recurse_struct * recurse_data = (struct recurse_struct *)data;
69 
70 	if (recurse_data->fn(dev, recurse_data->obj))
71 		return 1;
72 	else
73 		return device_for_each_child(dev, recurse_data, descend_children);
74 }
75 
76 /**
77  *	for_each_padev - Iterate over all devices in the tree
78  *	@fn:	Function to call for each device.
79  *	@data:	Data to pass to the called function.
80  *
81  *	This performs a depth-first traversal of the tree, calling the
82  *	function passed for each node.  It calls the function for parents
83  *	before children.
84  */
85 
86 static int for_each_padev(int (*fn)(struct device *, void *), void * data)
87 {
88 	struct recurse_struct recurse_data = {
89 		.obj	= data,
90 		.fn	= fn,
91 	};
92 	return device_for_each_child(&root, &recurse_data, descend_children);
93 }
94 
95 /**
96  * match_device - Report whether this driver can handle this device
97  * @driver: the PA-RISC driver to try
98  * @dev: the PA-RISC device to try
99  */
100 static int match_device(struct parisc_driver *driver, struct parisc_device *dev)
101 {
102 	const struct parisc_device_id *ids;
103 
104 	for (ids = driver->id_table; ids->sversion; ids++) {
105 		if ((ids->sversion != SVERSION_ANY_ID) &&
106 		    (ids->sversion != dev->id.sversion))
107 			continue;
108 
109 		if ((ids->hw_type != HWTYPE_ANY_ID) &&
110 		    (ids->hw_type != dev->id.hw_type))
111 			continue;
112 
113 		if ((ids->hversion != HVERSION_ANY_ID) &&
114 		    (ids->hversion != dev->id.hversion))
115 			continue;
116 
117 		return 1;
118 	}
119 	return 0;
120 }
121 
122 static int parisc_driver_probe(struct device *dev)
123 {
124 	int rc;
125 	struct parisc_device *pa_dev = to_parisc_device(dev);
126 	struct parisc_driver *pa_drv = to_parisc_driver(dev->driver);
127 
128 	rc = pa_drv->probe(pa_dev);
129 
130 	if (!rc)
131 		pa_dev->driver = pa_drv;
132 
133 	return rc;
134 }
135 
136 static int __exit parisc_driver_remove(struct device *dev)
137 {
138 	struct parisc_device *pa_dev = to_parisc_device(dev);
139 	struct parisc_driver *pa_drv = to_parisc_driver(dev->driver);
140 	if (pa_drv->remove)
141 		pa_drv->remove(pa_dev);
142 
143 	return 0;
144 }
145 
146 
147 /**
148  * register_parisc_driver - Register this driver if it can handle a device
149  * @driver: the PA-RISC driver to try
150  */
151 int register_parisc_driver(struct parisc_driver *driver)
152 {
153 	/* FIXME: we need this because apparently the sti
154 	 * driver can be registered twice */
155 	if (driver->drv.name) {
156 		pr_warn("BUG: skipping previously registered driver %s\n",
157 			driver->name);
158 		return 1;
159 	}
160 
161 	if (!driver->probe) {
162 		pr_warn("BUG: driver %s has no probe routine\n", driver->name);
163 		return 1;
164 	}
165 
166 	driver->drv.bus = &parisc_bus_type;
167 
168 	/* We install our own probe and remove routines */
169 	WARN_ON(driver->drv.probe != NULL);
170 	WARN_ON(driver->drv.remove != NULL);
171 
172 	driver->drv.name = driver->name;
173 
174 	return driver_register(&driver->drv);
175 }
176 EXPORT_SYMBOL(register_parisc_driver);
177 
178 
179 struct match_count {
180 	struct parisc_driver * driver;
181 	int count;
182 };
183 
184 static int match_and_count(struct device * dev, void * data)
185 {
186 	struct match_count * m = data;
187 	struct parisc_device * pdev = to_parisc_device(dev);
188 
189 	if (check_dev(dev)) {
190 		if (match_device(m->driver, pdev))
191 			m->count++;
192 	}
193 	return 0;
194 }
195 
196 /**
197  * count_parisc_driver - count # of devices this driver would match
198  * @driver: the PA-RISC driver to try
199  *
200  * Use by IOMMU support to "guess" the right size IOPdir.
201  * Formula is something like memsize/(num_iommu * entry_size).
202  */
203 int __init count_parisc_driver(struct parisc_driver *driver)
204 {
205 	struct match_count m = {
206 		.driver	= driver,
207 		.count	= 0,
208 	};
209 
210 	for_each_padev(match_and_count, &m);
211 
212 	return m.count;
213 }
214 
215 
216 
217 /**
218  * unregister_parisc_driver - Unregister this driver from the list of drivers
219  * @driver: the PA-RISC driver to unregister
220  */
221 int unregister_parisc_driver(struct parisc_driver *driver)
222 {
223 	driver_unregister(&driver->drv);
224 	return 0;
225 }
226 EXPORT_SYMBOL(unregister_parisc_driver);
227 
228 struct find_data {
229 	unsigned long hpa;
230 	struct parisc_device * dev;
231 };
232 
233 static int find_device(struct device * dev, void * data)
234 {
235 	struct parisc_device * pdev = to_parisc_device(dev);
236 	struct find_data * d = (struct find_data*)data;
237 
238 	if (check_dev(dev)) {
239 		if (pdev->hpa.start == d->hpa) {
240 			d->dev = pdev;
241 			return 1;
242 		}
243 	}
244 	return 0;
245 }
246 
247 static struct parisc_device *find_device_by_addr(unsigned long hpa)
248 {
249 	struct find_data d = {
250 		.hpa	= hpa,
251 	};
252 	int ret;
253 
254 	ret = for_each_padev(find_device, &d);
255 	return ret ? d.dev : NULL;
256 }
257 
258 static int __init is_IKE_device(struct device *dev, void *data)
259 {
260 	struct parisc_device *pdev = to_parisc_device(dev);
261 
262 	if (!check_dev(dev))
263 		return 0;
264 	if (pdev->id.hw_type != HPHW_BCPORT)
265 		return 0;
266 	if (IS_IKE(pdev) ||
267 		(pdev->id.hversion == REO_MERCED_PORT) ||
268 		(pdev->id.hversion == REOG_MERCED_PORT)) {
269 			return 1;
270 	}
271 	return 0;
272 }
273 
274 int __init machine_has_merced_bus(void)
275 {
276 	int ret;
277 
278 	ret = for_each_padev(is_IKE_device, NULL);
279 	return ret ? 1 : 0;
280 }
281 
282 /**
283  * find_pa_parent_type - Find a parent of a specific type
284  * @dev: The device to start searching from
285  * @type: The device type to search for.
286  *
287  * Walks up the device tree looking for a device of the specified type.
288  * If it finds it, it returns it.  If not, it returns NULL.
289  */
290 const struct parisc_device *
291 find_pa_parent_type(const struct parisc_device *padev, int type)
292 {
293 	const struct device *dev = &padev->dev;
294 	while (dev != &root) {
295 		struct parisc_device *candidate = to_parisc_device(dev);
296 		if (candidate->id.hw_type == type)
297 			return candidate;
298 		dev = dev->parent;
299 	}
300 
301 	return NULL;
302 }
303 
304 /*
305  * get_node_path fills in @path with the firmware path to the device.
306  * Note that if @node is a parisc device, we don't fill in the 'mod' field.
307  * This is because both callers pass the parent and fill in the mod
308  * themselves.  If @node is a PCI device, we do fill it in, even though this
309  * is inconsistent.
310  */
311 static void get_node_path(struct device *dev, struct hardware_path *path)
312 {
313 	int i = 5;
314 	memset(&path->bc, -1, 6);
315 
316 	if (dev_is_pci(dev)) {
317 		unsigned int devfn = to_pci_dev(dev)->devfn;
318 		path->mod = PCI_FUNC(devfn);
319 		path->bc[i--] = PCI_SLOT(devfn);
320 		dev = dev->parent;
321 	}
322 
323 	while (dev != &root) {
324 		if (dev_is_pci(dev)) {
325 			unsigned int devfn = to_pci_dev(dev)->devfn;
326 			path->bc[i--] = PCI_SLOT(devfn) | (PCI_FUNC(devfn)<< 5);
327 		} else if (dev->bus == &parisc_bus_type) {
328 			path->bc[i--] = to_parisc_device(dev)->hw_path;
329 		}
330 		dev = dev->parent;
331 	}
332 }
333 
334 static char *print_hwpath(struct hardware_path *path, char *output)
335 {
336 	int i;
337 	for (i = 0; i < 6; i++) {
338 		if (path->bc[i] == -1)
339 			continue;
340 		output += sprintf(output, "%u/", (unsigned char) path->bc[i]);
341 	}
342 	output += sprintf(output, "%u", (unsigned char) path->mod);
343 	return output;
344 }
345 
346 /**
347  * print_pa_hwpath - Returns hardware path for PA devices
348  * dev: The device to return the path for
349  * output: Pointer to a previously-allocated array to place the path in.
350  *
351  * This function fills in the output array with a human-readable path
352  * to a PA device.  This string is compatible with that used by PDC, and
353  * may be printed on the outside of the box.
354  */
355 char *print_pa_hwpath(struct parisc_device *dev, char *output)
356 {
357 	struct hardware_path path;
358 
359 	get_node_path(dev->dev.parent, &path);
360 	path.mod = dev->hw_path;
361 	return print_hwpath(&path, output);
362 }
363 EXPORT_SYMBOL(print_pa_hwpath);
364 
365 #if defined(CONFIG_PCI) || defined(CONFIG_ISA)
366 /**
367  * get_pci_node_path - Determines the hardware path for a PCI device
368  * @pdev: The device to return the path for
369  * @path: Pointer to a previously-allocated array to place the path in.
370  *
371  * This function fills in the hardware_path structure with the route to
372  * the specified PCI device.  This structure is suitable for passing to
373  * PDC calls.
374  */
375 void get_pci_node_path(struct pci_dev *pdev, struct hardware_path *path)
376 {
377 	get_node_path(&pdev->dev, path);
378 }
379 EXPORT_SYMBOL(get_pci_node_path);
380 
381 /**
382  * print_pci_hwpath - Returns hardware path for PCI devices
383  * dev: The device to return the path for
384  * output: Pointer to a previously-allocated array to place the path in.
385  *
386  * This function fills in the output array with a human-readable path
387  * to a PCI device.  This string is compatible with that used by PDC, and
388  * may be printed on the outside of the box.
389  */
390 char *print_pci_hwpath(struct pci_dev *dev, char *output)
391 {
392 	struct hardware_path path;
393 
394 	get_pci_node_path(dev, &path);
395 	return print_hwpath(&path, output);
396 }
397 EXPORT_SYMBOL(print_pci_hwpath);
398 
399 #endif /* defined(CONFIG_PCI) || defined(CONFIG_ISA) */
400 
401 static void setup_bus_id(struct parisc_device *padev)
402 {
403 	struct hardware_path path;
404 	char name[28];
405 	char *output = name;
406 	int i;
407 
408 	get_node_path(padev->dev.parent, &path);
409 
410 	for (i = 0; i < 6; i++) {
411 		if (path.bc[i] == -1)
412 			continue;
413 		output += sprintf(output, "%u:", (unsigned char) path.bc[i]);
414 	}
415 	sprintf(output, "%u", (unsigned char) padev->hw_path);
416 	dev_set_name(&padev->dev, name);
417 }
418 
419 struct parisc_device * __init create_tree_node(char id, struct device *parent)
420 {
421 	struct parisc_device *dev = kzalloc(sizeof(*dev), GFP_KERNEL);
422 	if (!dev)
423 		return NULL;
424 
425 	dev->hw_path = id;
426 	dev->id.hw_type = HPHW_FAULTY;
427 
428 	dev->dev.parent = parent;
429 	setup_bus_id(dev);
430 
431 	dev->dev.bus = &parisc_bus_type;
432 	dev->dma_mask = 0xffffffffUL;	/* PARISC devices are 32-bit */
433 
434 	/* make the generic dma mask a pointer to the parisc one */
435 	dev->dev.dma_mask = &dev->dma_mask;
436 	dev->dev.coherent_dma_mask = dev->dma_mask;
437 	if (device_register(&dev->dev)) {
438 		kfree(dev);
439 		return NULL;
440 	}
441 
442 	return dev;
443 }
444 
445 struct match_id_data {
446 	char id;
447 	struct parisc_device * dev;
448 };
449 
450 static int match_by_id(struct device * dev, void * data)
451 {
452 	struct parisc_device * pdev = to_parisc_device(dev);
453 	struct match_id_data * d = data;
454 
455 	if (pdev->hw_path == d->id) {
456 		d->dev = pdev;
457 		return 1;
458 	}
459 	return 0;
460 }
461 
462 /**
463  * alloc_tree_node - returns a device entry in the iotree
464  * @parent: the parent node in the tree
465  * @id: the element of the module path for this entry
466  *
467  * Checks all the children of @parent for a matching @id.  If none
468  * found, it allocates a new device and returns it.
469  */
470 static struct parisc_device * __init alloc_tree_node(
471 			struct device *parent, char id)
472 {
473 	struct match_id_data d = {
474 		.id = id,
475 	};
476 	if (device_for_each_child(parent, &d, match_by_id))
477 		return d.dev;
478 	else
479 		return create_tree_node(id, parent);
480 }
481 
482 static struct parisc_device *create_parisc_device(struct hardware_path *modpath)
483 {
484 	int i;
485 	struct device *parent = &root;
486 	for (i = 0; i < 6; i++) {
487 		if (modpath->bc[i] == -1)
488 			continue;
489 		parent = &alloc_tree_node(parent, modpath->bc[i])->dev;
490 	}
491 	return alloc_tree_node(parent, modpath->mod);
492 }
493 
494 struct parisc_device * __init
495 alloc_pa_dev(unsigned long hpa, struct hardware_path *mod_path)
496 {
497 	int status;
498 	unsigned long bytecnt;
499 	u8 iodc_data[32];
500 	struct parisc_device *dev;
501 	const char *name;
502 
503 	/* Check to make sure this device has not already been added - Ryan */
504 	if (find_device_by_addr(hpa) != NULL)
505 		return NULL;
506 
507 	status = pdc_iodc_read(&bytecnt, hpa, 0, &iodc_data, 32);
508 	if (status != PDC_OK)
509 		return NULL;
510 
511 	dev = create_parisc_device(mod_path);
512 	if (dev->id.hw_type != HPHW_FAULTY) {
513 		pr_err("Two devices have hardware path [%s].  IODC data for second device: %7phN\n"
514 		       "Rearranging GSC cards sometimes helps\n",
515 			parisc_pathname(dev), iodc_data);
516 		return NULL;
517 	}
518 
519 	dev->id.hw_type = iodc_data[3] & 0x1f;
520 	dev->id.hversion = (iodc_data[0] << 4) | ((iodc_data[1] & 0xf0) >> 4);
521 	dev->id.hversion_rev = iodc_data[1] & 0x0f;
522 	dev->id.sversion = ((iodc_data[4] & 0x0f) << 16) |
523 			(iodc_data[5] << 8) | iodc_data[6];
524 	dev->hpa.name = parisc_pathname(dev);
525 	dev->hpa.start = hpa;
526 	/* This is awkward.  The STI spec says that gfx devices may occupy
527 	 * 32MB or 64MB.  Unfortunately, we don't know how to tell whether
528 	 * it's the former or the latter.  Assumptions either way can hurt us.
529 	 */
530 	if (hpa == 0xf4000000 || hpa == 0xf8000000) {
531 		dev->hpa.end = hpa + 0x03ffffff;
532 	} else if (hpa == 0xf6000000 || hpa == 0xfa000000) {
533 		dev->hpa.end = hpa + 0x01ffffff;
534 	} else {
535 		dev->hpa.end = hpa + 0xfff;
536 	}
537 	dev->hpa.flags = IORESOURCE_MEM;
538 	name = parisc_hardware_description(&dev->id);
539 	if (name) {
540 		strlcpy(dev->name, name, sizeof(dev->name));
541 	}
542 
543 	/* Silently fail things like mouse ports which are subsumed within
544 	 * the keyboard controller
545 	 */
546 	if ((hpa & 0xfff) == 0 && insert_resource(&iomem_resource, &dev->hpa))
547 		pr_warn("Unable to claim HPA %lx for device %s\n", hpa, name);
548 
549 	return dev;
550 }
551 
552 static int parisc_generic_match(struct device *dev, struct device_driver *drv)
553 {
554 	return match_device(to_parisc_driver(drv), to_parisc_device(dev));
555 }
556 
557 static ssize_t make_modalias(struct device *dev, char *buf)
558 {
559 	const struct parisc_device *padev = to_parisc_device(dev);
560 	const struct parisc_device_id *id = &padev->id;
561 
562 	return sprintf(buf, "parisc:t%02Xhv%04Xrev%02Xsv%08X\n",
563 		(u8)id->hw_type, (u16)id->hversion, (u8)id->hversion_rev,
564 		(u32)id->sversion);
565 }
566 
567 static int parisc_uevent(struct device *dev, struct kobj_uevent_env *env)
568 {
569 	const struct parisc_device *padev;
570 	char modalias[40];
571 
572 	if (!dev)
573 		return -ENODEV;
574 
575 	padev = to_parisc_device(dev);
576 	if (!padev)
577 		return -ENODEV;
578 
579 	if (add_uevent_var(env, "PARISC_NAME=%s", padev->name))
580 		return -ENOMEM;
581 
582 	make_modalias(dev, modalias);
583 	if (add_uevent_var(env, "MODALIAS=%s", modalias))
584 		return -ENOMEM;
585 
586 	return 0;
587 }
588 
589 #define pa_dev_attr(name, field, format_string)				\
590 static ssize_t name##_show(struct device *dev, struct device_attribute *attr, char *buf)		\
591 {									\
592 	struct parisc_device *padev = to_parisc_device(dev);		\
593 	return sprintf(buf, format_string, padev->field);		\
594 }									\
595 static DEVICE_ATTR_RO(name);
596 
597 #define pa_dev_attr_id(field, format) pa_dev_attr(field, id.field, format)
598 
599 pa_dev_attr(irq, irq, "%u\n");
600 pa_dev_attr_id(hw_type, "0x%02x\n");
601 pa_dev_attr(rev, id.hversion_rev, "0x%x\n");
602 pa_dev_attr_id(hversion, "0x%03x\n");
603 pa_dev_attr_id(sversion, "0x%05x\n");
604 
605 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf)
606 {
607 	return make_modalias(dev, buf);
608 }
609 static DEVICE_ATTR_RO(modalias);
610 
611 static struct attribute *parisc_device_attrs[] = {
612 	&dev_attr_irq.attr,
613 	&dev_attr_hw_type.attr,
614 	&dev_attr_rev.attr,
615 	&dev_attr_hversion.attr,
616 	&dev_attr_sversion.attr,
617 	&dev_attr_modalias.attr,
618 	NULL,
619 };
620 ATTRIBUTE_GROUPS(parisc_device);
621 
622 struct bus_type parisc_bus_type = {
623 	.name = "parisc",
624 	.match = parisc_generic_match,
625 	.uevent = parisc_uevent,
626 	.dev_groups = parisc_device_groups,
627 	.probe = parisc_driver_probe,
628 	.remove = __exit_p(parisc_driver_remove),
629 };
630 
631 /**
632  * register_parisc_device - Locate a driver to manage this device.
633  * @dev: The parisc device.
634  *
635  * Search the driver list for a driver that is willing to manage
636  * this device.
637  */
638 int __init register_parisc_device(struct parisc_device *dev)
639 {
640 	if (!dev)
641 		return 0;
642 
643 	if (dev->driver)
644 		return 1;
645 
646 	return 0;
647 }
648 
649 /**
650  * match_pci_device - Matches a pci device against a given hardware path
651  * entry.
652  * @dev: the generic device (known to be contained by a pci_dev).
653  * @index: the current BC index
654  * @modpath: the hardware path.
655  * @return: true if the device matches the hardware path.
656  */
657 static int match_pci_device(struct device *dev, int index,
658 		struct hardware_path *modpath)
659 {
660 	struct pci_dev *pdev = to_pci_dev(dev);
661 	int id;
662 
663 	if (index == 5) {
664 		/* we are at the end of the path, and on the actual device */
665 		unsigned int devfn = pdev->devfn;
666 		return ((modpath->bc[5] == PCI_SLOT(devfn)) &&
667 					(modpath->mod == PCI_FUNC(devfn)));
668 	}
669 
670 	/* index might be out of bounds for bc[] */
671 	if (index >= 6)
672 		return 0;
673 
674 	id = PCI_SLOT(pdev->devfn) | (PCI_FUNC(pdev->devfn) << 5);
675 	return (modpath->bc[index] == id);
676 }
677 
678 /**
679  * match_parisc_device - Matches a parisc device against a given hardware
680  * path entry.
681  * @dev: the generic device (known to be contained by a parisc_device).
682  * @index: the current BC index
683  * @modpath: the hardware path.
684  * @return: true if the device matches the hardware path.
685  */
686 static int match_parisc_device(struct device *dev, int index,
687 		struct hardware_path *modpath)
688 {
689 	struct parisc_device *curr = to_parisc_device(dev);
690 	char id = (index == 6) ? modpath->mod : modpath->bc[index];
691 
692 	return (curr->hw_path == id);
693 }
694 
695 struct parse_tree_data {
696 	int index;
697 	struct hardware_path * modpath;
698 	struct device * dev;
699 };
700 
701 static int check_parent(struct device * dev, void * data)
702 {
703 	struct parse_tree_data * d = data;
704 
705 	if (check_dev(dev)) {
706 		if (dev->bus == &parisc_bus_type) {
707 			if (match_parisc_device(dev, d->index, d->modpath))
708 				d->dev = dev;
709 		} else if (dev_is_pci(dev)) {
710 			if (match_pci_device(dev, d->index, d->modpath))
711 				d->dev = dev;
712 		} else if (dev->bus == NULL) {
713 			/* we are on a bus bridge */
714 			struct device *new = parse_tree_node(dev, d->index, d->modpath);
715 			if (new)
716 				d->dev = new;
717 		}
718 	}
719 	return d->dev != NULL;
720 }
721 
722 /**
723  * parse_tree_node - returns a device entry in the iotree
724  * @parent: the parent node in the tree
725  * @index: the current BC index
726  * @modpath: the hardware_path struct to match a device against
727  * @return: The corresponding device if found, NULL otherwise.
728  *
729  * Checks all the children of @parent for a matching @id.  If none
730  * found, it returns NULL.
731  */
732 static struct device *
733 parse_tree_node(struct device *parent, int index, struct hardware_path *modpath)
734 {
735 	struct parse_tree_data d = {
736 		.index          = index,
737 		.modpath        = modpath,
738 	};
739 
740 	struct recurse_struct recurse_data = {
741 		.obj	= &d,
742 		.fn	= check_parent,
743 	};
744 
745 	if (device_for_each_child(parent, &recurse_data, descend_children))
746 		/* nothing */;
747 
748 	return d.dev;
749 }
750 
751 /**
752  * hwpath_to_device - Finds the generic device corresponding to a given hardware path.
753  * @modpath: the hardware path.
754  * @return: The target device, NULL if not found.
755  */
756 struct device *hwpath_to_device(struct hardware_path *modpath)
757 {
758 	int i;
759 	struct device *parent = &root;
760 	for (i = 0; i < 6; i++) {
761 		if (modpath->bc[i] == -1)
762 			continue;
763 		parent = parse_tree_node(parent, i, modpath);
764 		if (!parent)
765 			return NULL;
766 	}
767 	if (dev_is_pci(parent)) /* pci devices already parse MOD */
768 		return parent;
769 	else
770 		return parse_tree_node(parent, 6, modpath);
771 }
772 EXPORT_SYMBOL(hwpath_to_device);
773 
774 /**
775  * device_to_hwpath - Populates the hwpath corresponding to the given device.
776  * @param dev the target device
777  * @param path pointer to a previously allocated hwpath struct to be filled in
778  */
779 void device_to_hwpath(struct device *dev, struct hardware_path *path)
780 {
781 	struct parisc_device *padev;
782 	if (dev->bus == &parisc_bus_type) {
783 		padev = to_parisc_device(dev);
784 		get_node_path(dev->parent, path);
785 		path->mod = padev->hw_path;
786 	} else if (dev_is_pci(dev)) {
787 		get_node_path(dev, path);
788 	}
789 }
790 EXPORT_SYMBOL(device_to_hwpath);
791 
792 #define BC_PORT_MASK 0x8
793 #define BC_LOWER_PORT 0x8
794 
795 #define BUS_CONVERTER(dev) \
796         ((dev->id.hw_type == HPHW_IOA) || (dev->id.hw_type == HPHW_BCPORT))
797 
798 #define IS_LOWER_PORT(dev) \
799         ((gsc_readl(dev->hpa.start + offsetof(struct bc_module, io_status)) \
800                 & BC_PORT_MASK) == BC_LOWER_PORT)
801 
802 #define MAX_NATIVE_DEVICES 64
803 #define NATIVE_DEVICE_OFFSET 0x1000
804 
805 #define FLEX_MASK 	F_EXTEND(0xfffc0000)
806 #define IO_IO_LOW	offsetof(struct bc_module, io_io_low)
807 #define IO_IO_HIGH	offsetof(struct bc_module, io_io_high)
808 #define READ_IO_IO_LOW(dev)  (unsigned long)(signed int)gsc_readl(dev->hpa.start + IO_IO_LOW)
809 #define READ_IO_IO_HIGH(dev) (unsigned long)(signed int)gsc_readl(dev->hpa.start + IO_IO_HIGH)
810 
811 static void walk_native_bus(unsigned long io_io_low, unsigned long io_io_high,
812                             struct device *parent);
813 
814 static void __init walk_lower_bus(struct parisc_device *dev)
815 {
816 	unsigned long io_io_low, io_io_high;
817 
818 	if (!BUS_CONVERTER(dev) || IS_LOWER_PORT(dev))
819 		return;
820 
821 	if (dev->id.hw_type == HPHW_IOA) {
822 		io_io_low = (unsigned long)(signed int)(READ_IO_IO_LOW(dev) << 16);
823 		io_io_high = io_io_low + MAX_NATIVE_DEVICES * NATIVE_DEVICE_OFFSET;
824 	} else {
825 		io_io_low = (READ_IO_IO_LOW(dev) + ~FLEX_MASK) & FLEX_MASK;
826 		io_io_high = (READ_IO_IO_HIGH(dev)+ ~FLEX_MASK) & FLEX_MASK;
827 	}
828 
829 	walk_native_bus(io_io_low, io_io_high, &dev->dev);
830 }
831 
832 /**
833  * walk_native_bus -- Probe a bus for devices
834  * @io_io_low: Base address of this bus.
835  * @io_io_high: Last address of this bus.
836  * @parent: The parent bus device.
837  *
838  * A native bus (eg Runway or GSC) may have up to 64 devices on it,
839  * spaced at intervals of 0x1000 bytes.  PDC may not inform us of these
840  * devices, so we have to probe for them.  Unfortunately, we may find
841  * devices which are not physically connected (such as extra serial &
842  * keyboard ports).  This problem is not yet solved.
843  */
844 static void __init walk_native_bus(unsigned long io_io_low,
845 	unsigned long io_io_high, struct device *parent)
846 {
847 	int i, devices_found = 0;
848 	unsigned long hpa = io_io_low;
849 	struct hardware_path path;
850 
851 	get_node_path(parent, &path);
852 	do {
853 		for(i = 0; i < MAX_NATIVE_DEVICES; i++, hpa += NATIVE_DEVICE_OFFSET) {
854 			struct parisc_device *dev;
855 
856 			/* Was the device already added by Firmware? */
857 			dev = find_device_by_addr(hpa);
858 			if (!dev) {
859 				path.mod = i;
860 				dev = alloc_pa_dev(hpa, &path);
861 				if (!dev)
862 					continue;
863 
864 				register_parisc_device(dev);
865 				devices_found++;
866 			}
867 			walk_lower_bus(dev);
868 		}
869 	} while(!devices_found && hpa < io_io_high);
870 }
871 
872 #define CENTRAL_BUS_ADDR F_EXTEND(0xfff80000)
873 
874 /**
875  * walk_central_bus - Find devices attached to the central bus
876  *
877  * PDC doesn't tell us about all devices in the system.  This routine
878  * finds devices connected to the central bus.
879  */
880 void __init walk_central_bus(void)
881 {
882 	walk_native_bus(CENTRAL_BUS_ADDR,
883 			CENTRAL_BUS_ADDR + (MAX_NATIVE_DEVICES * NATIVE_DEVICE_OFFSET),
884 			&root);
885 }
886 
887 static void print_parisc_device(struct parisc_device *dev)
888 {
889 	char hw_path[64];
890 	static int count;
891 
892 	print_pa_hwpath(dev, hw_path);
893 	pr_info("%d. %s at %pap [%s] { %d, 0x%x, 0x%.3x, 0x%.5x }",
894 		++count, dev->name, &(dev->hpa.start), hw_path, dev->id.hw_type,
895 		dev->id.hversion_rev, dev->id.hversion, dev->id.sversion);
896 
897 	if (dev->num_addrs) {
898 		int k;
899 		pr_cont(", additional addresses: ");
900 		for (k = 0; k < dev->num_addrs; k++)
901 			pr_cont("0x%lx ", dev->addr[k]);
902 	}
903 	pr_cont("\n");
904 }
905 
906 /**
907  * init_parisc_bus - Some preparation to be done before inventory
908  */
909 void __init init_parisc_bus(void)
910 {
911 	if (bus_register(&parisc_bus_type))
912 		panic("Could not register PA-RISC bus type\n");
913 	if (device_register(&root))
914 		panic("Could not register PA-RISC root device\n");
915 	get_device(&root);
916 }
917 
918 static __init void qemu_header(void)
919 {
920 	int num;
921 	unsigned long *p;
922 
923 	pr_info("--- cut here ---\n");
924 	pr_info("/* AUTO-GENERATED HEADER FILE FOR SEABIOS FIRMWARE */\n");
925 	pr_cont("/* generated with Linux kernel */\n");
926 	pr_cont("/* search for PARISC_QEMU_MACHINE_HEADER in Linux */\n\n");
927 
928 	pr_info("#define PARISC_MODEL \"%s\"\n\n",
929 			boot_cpu_data.pdc.sys_model_name);
930 
931 	pr_info("#define PARISC_PDC_MODEL 0x%lx, 0x%lx, 0x%lx, "
932 		"0x%lx, 0x%lx, 0x%lx, 0x%lx, 0x%lx, 0x%lx\n\n",
933 	#define p ((unsigned long *)&boot_cpu_data.pdc.model)
934 		p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8]);
935 	#undef p
936 
937 	pr_info("#define PARISC_PDC_VERSION 0x%04lx\n\n",
938 			boot_cpu_data.pdc.versions);
939 
940 	pr_info("#define PARISC_PDC_CPUID 0x%04lx\n\n",
941 			boot_cpu_data.pdc.cpuid);
942 
943 	pr_info("#define PARISC_PDC_CAPABILITIES 0x%04lx\n\n",
944 			boot_cpu_data.pdc.capabilities);
945 
946 	pr_info("#define PARISC_PDC_ENTRY_ORG 0x%04lx\n\n",
947 #ifdef CONFIG_64BIT
948 		(unsigned long)(PAGE0->mem_pdc_hi) << 32 |
949 #endif
950 		(unsigned long)PAGE0->mem_pdc);
951 
952 	pr_info("#define PARISC_PDC_CACHE_INFO");
953 	p = (unsigned long *) &cache_info;
954 	for (num = 0; num < sizeof(cache_info); num += sizeof(unsigned long)) {
955 		if (((num % 5) == 0)) {
956 			pr_cont(" \\\n");
957 			pr_info("\t");
958 		}
959 		pr_cont("%s0x%04lx",
960 			num?", ":"", *p++);
961 	}
962 	pr_cont("\n\n");
963 }
964 
965 static __init int qemu_print_hpa(struct device *lin_dev, void *data)
966 {
967 	struct parisc_device *dev = to_parisc_device(lin_dev);
968 	unsigned long hpa = dev->hpa.start;
969 
970 	pr_cont("\t{\t.hpa = 0x%08lx,\\\n", hpa);
971 	pr_cont("\t\t.iodc = &iodc_data_hpa_%08lx,\\\n", hpa);
972 	pr_cont("\t\t.mod_info = &mod_info_hpa_%08lx,\\\n", hpa);
973 	pr_cont("\t\t.mod_path = &mod_path_hpa_%08lx,\\\n", hpa);
974 	pr_cont("\t\t.num_addr = HPA_%08lx_num_addr,\\\n", hpa);
975 	pr_cont("\t\t.add_addr = { HPA_%08lx_add_addr } },\\\n", hpa);
976 	return 0;
977 }
978 
979 
980 static __init void qemu_footer(void)
981 {
982 	pr_info("\n\n#define PARISC_DEVICE_LIST \\\n");
983 	for_each_padev(qemu_print_hpa, NULL);
984 	pr_cont("\t{ 0, }\n");
985 	pr_info("--- cut here ---\n");
986 }
987 
988 /* print iodc data of the various hpa modules for qemu inclusion */
989 static __init int qemu_print_iodc_data(struct device *lin_dev, void *data)
990 {
991 	struct parisc_device *dev = to_parisc_device(lin_dev);
992 	unsigned long count;
993 	unsigned long hpa = dev->hpa.start;
994 	int status;
995 	struct pdc_iodc iodc_data;
996 
997 	int mod_index;
998 	struct pdc_system_map_mod_info pdc_mod_info;
999 	struct pdc_module_path mod_path;
1000 
1001 	status = pdc_iodc_read(&count, hpa, 0,
1002 		&iodc_data, sizeof(iodc_data));
1003 	if (status != PDC_OK) {
1004 		pr_info("No IODC data for hpa 0x%08lx\n", hpa);
1005 		return 0;
1006 	}
1007 
1008 	pr_info("\n");
1009 
1010 	pr_info("#define HPA_%08lx_DESCRIPTION \"%s\"\n",
1011 		hpa, parisc_hardware_description(&dev->id));
1012 
1013 	mod_index = 0;
1014 	do {
1015 		status = pdc_system_map_find_mods(&pdc_mod_info,
1016 				&mod_path, mod_index++);
1017 	} while (status == PDC_OK && pdc_mod_info.mod_addr != hpa);
1018 
1019 	pr_info("static struct pdc_system_map_mod_info"
1020 		" mod_info_hpa_%08lx = {\n", hpa);
1021 	#define DO(member) \
1022 		pr_cont("\t." #member " = 0x%x,\n", \
1023 			(unsigned int)pdc_mod_info.member)
1024 	DO(mod_addr);
1025 	DO(mod_pgs);
1026 	DO(add_addrs);
1027 	pr_cont("};\n");
1028 	#undef DO
1029 	pr_info("static struct pdc_module_path "
1030 		"mod_path_hpa_%08lx = {\n", hpa);
1031 	pr_cont("\t.path = { ");
1032 	pr_cont(".flags = 0x%x, ", mod_path.path.flags);
1033 	pr_cont(".bc = { 0x%x, 0x%x, 0x%x, 0x%x, 0x%x, 0x%x }, ",
1034 		(unsigned char)mod_path.path.bc[0],
1035 		(unsigned char)mod_path.path.bc[1],
1036 		(unsigned char)mod_path.path.bc[2],
1037 		(unsigned char)mod_path.path.bc[3],
1038 		(unsigned char)mod_path.path.bc[4],
1039 		(unsigned char)mod_path.path.bc[5]);
1040 	pr_cont(".mod = 0x%x ", mod_path.path.mod);
1041 	pr_cont(" },\n");
1042 	pr_cont("\t.layers = { 0x%x, 0x%x, 0x%x, 0x%x, 0x%x, 0x%x }\n",
1043 		mod_path.layers[0], mod_path.layers[1], mod_path.layers[2],
1044 		mod_path.layers[3], mod_path.layers[4], mod_path.layers[5]);
1045 	pr_cont("};\n");
1046 
1047 	pr_info("static struct pdc_iodc iodc_data_hpa_%08lx = {\n", hpa);
1048 	#define DO(member) \
1049 		pr_cont("\t." #member " = 0x%04lx,\n", \
1050 			(unsigned long)iodc_data.member)
1051 	DO(hversion_model);
1052 	DO(hversion);
1053 	DO(spa);
1054 	DO(type);
1055 	DO(sversion_rev);
1056 	DO(sversion_model);
1057 	DO(sversion_opt);
1058 	DO(rev);
1059 	DO(dep);
1060 	DO(features);
1061 	DO(checksum);
1062 	DO(length);
1063 	#undef DO
1064 	pr_cont("\t/* pad: 0x%04x, 0x%04x */\n",
1065 		iodc_data.pad[0], iodc_data.pad[1]);
1066 	pr_cont("};\n");
1067 
1068 	pr_info("#define HPA_%08lx_num_addr %d\n", hpa, dev->num_addrs);
1069 	pr_info("#define HPA_%08lx_add_addr ", hpa);
1070 	count = 0;
1071 	if (dev->num_addrs == 0)
1072 		pr_cont("0");
1073 	while (count < dev->num_addrs) {
1074 		pr_cont("0x%08lx, ", dev->addr[count]);
1075 		count++;
1076 	}
1077 	pr_cont("\n\n");
1078 
1079 	return 0;
1080 }
1081 
1082 
1083 
1084 static int print_one_device(struct device * dev, void * data)
1085 {
1086 	struct parisc_device * pdev = to_parisc_device(dev);
1087 
1088 	if (check_dev(dev))
1089 		print_parisc_device(pdev);
1090 	return 0;
1091 }
1092 
1093 /**
1094  * print_parisc_devices - Print out a list of devices found in this system
1095  */
1096 void __init print_parisc_devices(void)
1097 {
1098 	for_each_padev(print_one_device, NULL);
1099 	#define PARISC_QEMU_MACHINE_HEADER 0
1100 	if (PARISC_QEMU_MACHINE_HEADER) {
1101 		qemu_header();
1102 		for_each_padev(qemu_print_iodc_data, NULL);
1103 		qemu_footer();
1104 	}
1105 }
1106