core.c revision 4ab55d8d4f7b910c4c60e0f8ff70d0dfdd484f02 
1/*
2 * pnpbios -- PnP BIOS driver
3 *
4 * This driver provides access to Plug-'n'-Play services provided by
5 * the PnP BIOS firmware, described in the following documents:
6 *   Plug and Play BIOS Specification, Version 1.0A, 5 May 1994
7 *   Plug and Play BIOS Clarification Paper, 6 October 1994
8 *     Compaq Computer Corporation, Phoenix Technologies Ltd., Intel Corp.
9 *
10 * Originally (C) 1998 Christian Schmidt <schmidt@digadd.de>
11 * Modifications (C) 1998 Tom Lees <tom@lpsg.demon.co.uk>
12 * Minor reorganizations by David Hinds <dahinds@users.sourceforge.net>
13 * Further modifications (C) 2001, 2002 by:
14 *   Alan Cox <alan@redhat.com>
15 *   Thomas Hood
16 *   Brian Gerst <bgerst@didntduck.org>
17 *
18 * Ported to the PnP Layer and several additional improvements (C) 2002
19 * by Adam Belay <ambx1@neo.rr.com>
20 *
21 * This program is free software; you can redistribute it and/or modify it
22 * under the terms of the GNU General Public License as published by the
23 * Free Software Foundation; either version 2, or (at your option) any
24 * later version.
25 *
26 * This program is distributed in the hope that it will be useful, but
27 * WITHOUT ANY WARRANTY; without even the implied warranty of
28 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
29 * General Public License for more details.
30 *
31 * You should have received a copy of the GNU General Public License
32 * along with this program; if not, write to the Free Software
33 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
34 */
35
36/* Change Log
37 *
38 * Adam Belay - <ambx1@neo.rr.com> - March 16, 2003
39 * rev 1.01	Only call pnp_bios_dev_node_info once
40 *		Added pnpbios_print_status
41 *		Added several new error messages and info messages
42 *		Added pnpbios_interface_attach_device
43 *		integrated core and proc init system
44 *		Introduced PNPMODE flags
45 *		Removed some useless includes
46 */
47
48#include <linux/types.h>
49#include <linux/module.h>
50#include <linux/init.h>
51#include <linux/linkage.h>
52#include <linux/kernel.h>
53#include <linux/pnpbios.h>
54#include <linux/device.h>
55#include <linux/pnp.h>
56#include <linux/mm.h>
57#include <linux/smp.h>
58#include <linux/slab.h>
59#include <linux/completion.h>
60#include <linux/spinlock.h>
61#include <linux/dmi.h>
62#include <linux/delay.h>
63#include <linux/acpi.h>
64#include <linux/freezer.h>
65#include <linux/kthread.h>
66
67#include <asm/page.h>
68#include <asm/desc.h>
69#include <asm/system.h>
70#include <asm/byteorder.h>
71
72#include "../base.h"
73#include "pnpbios.h"
74
75/*
76 *
77 * PnP BIOS INTERFACE
78 *
79 */
80
81static union pnp_bios_install_struct *pnp_bios_install = NULL;
82
83int pnp_bios_present(void)
84{
85	return (pnp_bios_install != NULL);
86}
87
88struct pnp_dev_node_info node_info;
89
90/*
91 *
92 * DOCKING FUNCTIONS
93 *
94 */
95
96#ifdef CONFIG_HOTPLUG
97
98static int unloading = 0;
99static struct completion unload_sem;
100
101/*
102 * (Much of this belongs in a shared routine somewhere)
103 */
104static int pnp_dock_event(int dock, struct pnp_docking_station_info *info)
105{
106	char *argv[3], **envp, *buf, *scratch;
107	int i = 0, value;
108
109	if (!(envp = kcalloc(20, sizeof(char *), GFP_KERNEL)))
110		return -ENOMEM;
111	if (!(buf = kzalloc(256, GFP_KERNEL))) {
112		kfree(envp);
113		return -ENOMEM;
114	}
115
116	/* FIXME: if there are actual users of this, it should be
117	 * integrated into the driver core and use the usual infrastructure
118	 * like sysfs and uevents
119	 */
120	argv[0] = "/sbin/pnpbios";
121	argv[1] = "dock";
122	argv[2] = NULL;
123
124	/* minimal command environment */
125	envp[i++] = "HOME=/";
126	envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
127
128#ifdef	DEBUG
129	/* hint that policy agent should enter no-stdout debug mode */
130	envp[i++] = "DEBUG=kernel";
131#endif
132	/* extensible set of named bus-specific parameters,
133	 * supporting multiple driver selection algorithms.
134	 */
135	scratch = buf;
136
137	/* action:  add, remove */
138	envp[i++] = scratch;
139	scratch += sprintf(scratch, "ACTION=%s", dock ? "add" : "remove") + 1;
140
141	/* Report the ident for the dock */
142	envp[i++] = scratch;
143	scratch += sprintf(scratch, "DOCK=%x/%x/%x",
144			   info->location_id, info->serial, info->capabilities);
145	envp[i] = NULL;
146
147	value = call_usermodehelper(argv [0], argv, envp, UMH_WAIT_EXEC);
148	kfree(buf);
149	kfree(envp);
150	return 0;
151}
152
153/*
154 * Poll the PnP docking at regular intervals
155 */
156static int pnp_dock_thread(void *unused)
157{
158	static struct pnp_docking_station_info now;
159	int docked = -1, d = 0;
160
161	set_freezable();
162	while (!unloading) {
163		int status;
164
165		/*
166		 * Poll every 2 seconds
167		 */
168		msleep_interruptible(2000);
169
170		if (try_to_freeze())
171			continue;
172
173		status = pnp_bios_dock_station_info(&now);
174
175		switch (status) {
176			/*
177			 * No dock to manage
178			 */
179		case PNP_FUNCTION_NOT_SUPPORTED:
180			complete_and_exit(&unload_sem, 0);
181		case PNP_SYSTEM_NOT_DOCKED:
182			d = 0;
183			break;
184		case PNP_SUCCESS:
185			d = 1;
186			break;
187		default:
188			pnpbios_print_status("pnp_dock_thread", status);
189			continue;
190		}
191		if (d != docked) {
192			if (pnp_dock_event(d, &now) == 0) {
193				docked = d;
194#if 0
195				printk(KERN_INFO
196				       "PnPBIOS: Docking station %stached\n",
197				       docked ? "at" : "de");
198#endif
199			}
200		}
201	}
202	complete_and_exit(&unload_sem, 0);
203}
204
205#endif				/* CONFIG_HOTPLUG */
206
207static int pnpbios_get_resources(struct pnp_dev *dev)
208{
209	u8 nodenum = dev->number;
210	struct pnp_bios_node *node;
211
212	if (!pnpbios_is_dynamic(dev))
213		return -EPERM;
214
215	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
216	if (!node)
217		return -1;
218	if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
219		kfree(node);
220		return -ENODEV;
221	}
222	pnpbios_read_resources_from_node(dev, node);
223	dev->active = pnp_is_active(dev);
224	kfree(node);
225	return 0;
226}
227
228static int pnpbios_set_resources(struct pnp_dev *dev)
229{
230	u8 nodenum = dev->number;
231	struct pnp_bios_node *node;
232	int ret;
233
234	if (!pnpbios_is_dynamic(dev))
235		return -EPERM;
236
237	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
238	if (!node)
239		return -1;
240	if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
241		kfree(node);
242		return -ENODEV;
243	}
244	if (pnpbios_write_resources_to_node(dev, node) < 0) {
245		kfree(node);
246		return -1;
247	}
248	ret = pnp_bios_set_dev_node(node->handle, (char)PNPMODE_DYNAMIC, node);
249	kfree(node);
250	if (ret > 0)
251		ret = -1;
252	return ret;
253}
254
255static void pnpbios_zero_data_stream(struct pnp_bios_node *node)
256{
257	unsigned char *p = (char *)node->data;
258	unsigned char *end = (char *)(node->data + node->size);
259	unsigned int len;
260	int i;
261
262	while ((char *)p < (char *)end) {
263		if (p[0] & 0x80) {	/* large tag */
264			len = (p[2] << 8) | p[1];
265			p += 3;
266		} else {
267			if (((p[0] >> 3) & 0x0f) == 0x0f)
268				return;
269			len = p[0] & 0x07;
270			p += 1;
271		}
272		for (i = 0; i < len; i++)
273			p[i] = 0;
274		p += len;
275	}
276	printk(KERN_ERR
277	       "PnPBIOS: Resource structure did not contain an end tag.\n");
278}
279
280static int pnpbios_disable_resources(struct pnp_dev *dev)
281{
282	struct pnp_bios_node *node;
283	u8 nodenum = dev->number;
284	int ret;
285
286	if (dev->flags & PNPBIOS_NO_DISABLE || !pnpbios_is_dynamic(dev))
287		return -EPERM;
288
289	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
290	if (!node)
291		return -ENOMEM;
292
293	if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
294		kfree(node);
295		return -ENODEV;
296	}
297	pnpbios_zero_data_stream(node);
298
299	ret = pnp_bios_set_dev_node(dev->number, (char)PNPMODE_DYNAMIC, node);
300	kfree(node);
301	if (ret > 0)
302		ret = -1;
303	return ret;
304}
305
306/* PnP Layer support */
307
308struct pnp_protocol pnpbios_protocol = {
309	.name = "Plug and Play BIOS",
310	.get = pnpbios_get_resources,
311	.set = pnpbios_set_resources,
312	.disable = pnpbios_disable_resources,
313};
314
315static int __init insert_device(struct pnp_bios_node *node)
316{
317	struct list_head *pos;
318	struct pnp_dev *dev;
319	char id[8];
320
321	/* check if the device is already added */
322	list_for_each(pos, &pnpbios_protocol.devices) {
323		dev = list_entry(pos, struct pnp_dev, protocol_list);
324		if (dev->number == node->handle)
325			return -1;
326	}
327
328	pnp_eisa_id_to_string(node->eisa_id & PNP_EISA_ID_MASK, id);
329	dev = pnp_alloc_dev(&pnpbios_protocol, node->handle, id);
330	if (!dev)
331		return -1;
332
333	pnpbios_parse_data_stream(dev, node);
334	dev->active = pnp_is_active(dev);
335	dev->flags = node->flags;
336	if (!(dev->flags & PNPBIOS_NO_CONFIG))
337		dev->capabilities |= PNP_CONFIGURABLE;
338	if (!(dev->flags & PNPBIOS_NO_DISABLE) && pnpbios_is_dynamic(dev))
339		dev->capabilities |= PNP_DISABLE;
340	dev->capabilities |= PNP_READ;
341	if (pnpbios_is_dynamic(dev))
342		dev->capabilities |= PNP_WRITE;
343	if (dev->flags & PNPBIOS_REMOVABLE)
344		dev->capabilities |= PNP_REMOVABLE;
345
346	/* clear out the damaged flags */
347	if (!dev->active)
348		pnp_init_resource_table(&dev->res);
349
350	pnp_add_device(dev);
351	pnpbios_interface_attach_device(node);
352
353	return 0;
354}
355
356static void __init build_devlist(void)
357{
358	u8 nodenum;
359	unsigned int nodes_got = 0;
360	unsigned int devs = 0;
361	struct pnp_bios_node *node;
362
363	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
364	if (!node)
365		return;
366
367	for (nodenum = 0; nodenum < 0xff;) {
368		u8 thisnodenum = nodenum;
369		/* eventually we will want to use PNPMODE_STATIC here but for now
370		 * dynamic will help us catch buggy bioses to add to the blacklist.
371		 */
372		if (!pnpbios_dont_use_current_config) {
373			if (pnp_bios_get_dev_node
374			    (&nodenum, (char)PNPMODE_DYNAMIC, node))
375				break;
376		} else {
377			if (pnp_bios_get_dev_node
378			    (&nodenum, (char)PNPMODE_STATIC, node))
379				break;
380		}
381		nodes_got++;
382		if (insert_device(node) == 0)
383			devs++;
384		if (nodenum <= thisnodenum) {
385			printk(KERN_ERR
386			       "PnPBIOS: build_devlist: Node number 0x%x is out of sequence following node 0x%x. Aborting.\n",
387			       (unsigned int)nodenum,
388			       (unsigned int)thisnodenum);
389			break;
390		}
391	}
392	kfree(node);
393
394	printk(KERN_INFO
395	       "PnPBIOS: %i node%s reported by PnP BIOS; %i recorded by driver\n",
396	       nodes_got, nodes_got != 1 ? "s" : "", devs);
397}
398
399/*
400 *
401 * INIT AND EXIT
402 *
403 */
404
405static int pnpbios_disabled;
406int pnpbios_dont_use_current_config;
407
408static int __init pnpbios_setup(char *str)
409{
410	int invert;
411
412	while ((str != NULL) && (*str != '\0')) {
413		if (strncmp(str, "off", 3) == 0)
414			pnpbios_disabled = 1;
415		if (strncmp(str, "on", 2) == 0)
416			pnpbios_disabled = 0;
417		invert = (strncmp(str, "no-", 3) == 0);
418		if (invert)
419			str += 3;
420		if (strncmp(str, "curr", 4) == 0)
421			pnpbios_dont_use_current_config = invert;
422		str = strchr(str, ',');
423		if (str != NULL)
424			str += strspn(str, ", \t");
425	}
426
427	return 1;
428}
429
430__setup("pnpbios=", pnpbios_setup);
431
432/* PnP BIOS signature: "$PnP" */
433#define PNP_SIGNATURE   (('$' << 0) + ('P' << 8) + ('n' << 16) + ('P' << 24))
434
435static int __init pnpbios_probe_system(void)
436{
437	union pnp_bios_install_struct *check;
438	u8 sum;
439	int length, i;
440
441	printk(KERN_INFO "PnPBIOS: Scanning system for PnP BIOS support...\n");
442
443	/*
444	 * Search the defined area (0xf0000-0xffff0) for a valid PnP BIOS
445	 * structure and, if one is found, sets up the selectors and
446	 * entry points
447	 */
448	for (check = (union pnp_bios_install_struct *)__va(0xf0000);
449	     check < (union pnp_bios_install_struct *)__va(0xffff0);
450	     check = (void *)check + 16) {
451		if (check->fields.signature != PNP_SIGNATURE)
452			continue;
453		printk(KERN_INFO
454		       "PnPBIOS: Found PnP BIOS installation structure at 0x%p\n",
455		       check);
456		length = check->fields.length;
457		if (!length) {
458			printk(KERN_ERR
459			       "PnPBIOS: installation structure is invalid, skipping\n");
460			continue;
461		}
462		for (sum = 0, i = 0; i < length; i++)
463			sum += check->chars[i];
464		if (sum) {
465			printk(KERN_ERR
466			       "PnPBIOS: installation structure is corrupted, skipping\n");
467			continue;
468		}
469		if (check->fields.version < 0x10) {
470			printk(KERN_WARNING
471			       "PnPBIOS: PnP BIOS version %d.%d is not supported\n",
472			       check->fields.version >> 4,
473			       check->fields.version & 15);
474			continue;
475		}
476		printk(KERN_INFO
477		       "PnPBIOS: PnP BIOS version %d.%d, entry 0x%x:0x%x, dseg 0x%x\n",
478		       check->fields.version >> 4, check->fields.version & 15,
479		       check->fields.pm16cseg, check->fields.pm16offset,
480		       check->fields.pm16dseg);
481		pnp_bios_install = check;
482		return 1;
483	}
484
485	printk(KERN_INFO "PnPBIOS: PnP BIOS support was not detected.\n");
486	return 0;
487}
488
489static int __init exploding_pnp_bios(const struct dmi_system_id *d)
490{
491	printk(KERN_WARNING "%s detected. Disabling PnPBIOS\n", d->ident);
492	return 0;
493}
494
495static struct dmi_system_id pnpbios_dmi_table[] __initdata = {
496	{			/* PnPBIOS GPF on boot */
497	 .callback = exploding_pnp_bios,
498	 .ident = "Higraded P14H",
499	 .matches = {
500		     DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
501		     DMI_MATCH(DMI_BIOS_VERSION, "07.00T"),
502		     DMI_MATCH(DMI_SYS_VENDOR, "Higraded"),
503		     DMI_MATCH(DMI_PRODUCT_NAME, "P14H"),
504		     },
505	 },
506	{			/* PnPBIOS GPF on boot */
507	 .callback = exploding_pnp_bios,
508	 .ident = "ASUS P4P800",
509	 .matches = {
510		     DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc."),
511		     DMI_MATCH(DMI_BOARD_NAME, "P4P800"),
512		     },
513	 },
514	{}
515};
516
517static int __init pnpbios_init(void)
518{
519	int ret;
520
521#if defined(CONFIG_PPC_MERGE)
522	if (check_legacy_ioport(PNPBIOS_BASE))
523		return -ENODEV;
524#endif
525	if (pnpbios_disabled || dmi_check_system(pnpbios_dmi_table) ||
526	    paravirt_enabled()) {
527		printk(KERN_INFO "PnPBIOS: Disabled\n");
528		return -ENODEV;
529	}
530#ifdef CONFIG_PNPACPI
531	if (!acpi_disabled && !pnpacpi_disabled) {
532		pnpbios_disabled = 1;
533		printk(KERN_INFO "PnPBIOS: Disabled by ACPI PNP\n");
534		return -ENODEV;
535	}
536#endif				/* CONFIG_ACPI */
537
538	/* scan the system for pnpbios support */
539	if (!pnpbios_probe_system())
540		return -ENODEV;
541
542	/* make preparations for bios calls */
543	pnpbios_calls_init(pnp_bios_install);
544
545	/* read the node info */
546	ret = pnp_bios_dev_node_info(&node_info);
547	if (ret) {
548		printk(KERN_ERR
549		       "PnPBIOS: Unable to get node info.  Aborting.\n");
550		return ret;
551	}
552
553	/* register with the pnp layer */
554	ret = pnp_register_protocol(&pnpbios_protocol);
555	if (ret) {
556		printk(KERN_ERR
557		       "PnPBIOS: Unable to register driver.  Aborting.\n");
558		return ret;
559	}
560
561	/* start the proc interface */
562	ret = pnpbios_proc_init();
563	if (ret)
564		printk(KERN_ERR "PnPBIOS: Failed to create proc interface.\n");
565
566	/* scan for pnpbios devices */
567	build_devlist();
568
569	pnp_platform_devices = 1;
570	return 0;
571}
572
573subsys_initcall(pnpbios_init);
574
575static int __init pnpbios_thread_init(void)
576{
577	struct task_struct *task;
578
579#if defined(CONFIG_PPC_MERGE)
580	if (check_legacy_ioport(PNPBIOS_BASE))
581		return 0;
582#endif
583	if (pnpbios_disabled)
584		return 0;
585#ifdef CONFIG_HOTPLUG
586	init_completion(&unload_sem);
587	task = kthread_run(pnp_dock_thread, NULL, "kpnpbiosd");
588	if (!IS_ERR(task))
589		unloading = 0;
590#endif
591	return 0;
592}
593
594/* Start the kernel thread later: */
595module_init(pnpbios_thread_init);
596
597EXPORT_SYMBOL(pnpbios_protocol);
598