core.c revision 9ffc93f203c18a70623f21950f1dd473c9ec48cd 
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/device.h>
54#include <linux/pnp.h>
55#include <linux/mm.h>
56#include <linux/smp.h>
57#include <linux/slab.h>
58#include <linux/completion.h>
59#include <linux/spinlock.h>
60#include <linux/dmi.h>
61#include <linux/delay.h>
62#include <linux/acpi.h>
63#include <linux/freezer.h>
64#include <linux/kthread.h>
65
66#include <asm/page.h>
67#include <asm/desc.h>
68#include <asm/byteorder.h>
69
70#include "../base.h"
71#include "pnpbios.h"
72
73/*
74 *
75 * PnP BIOS INTERFACE
76 *
77 */
78
79static union pnp_bios_install_struct *pnp_bios_install = NULL;
80
81int pnp_bios_present(void)
82{
83	return (pnp_bios_install != NULL);
84}
85
86struct pnp_dev_node_info node_info;
87
88/*
89 *
90 * DOCKING FUNCTIONS
91 *
92 */
93
94#ifdef CONFIG_HOTPLUG
95
96static struct completion unload_sem;
97
98/*
99 * (Much of this belongs in a shared routine somewhere)
100 */
101static int pnp_dock_event(int dock, struct pnp_docking_station_info *info)
102{
103	char *argv[3], **envp, *buf, *scratch;
104	int i = 0, value;
105
106	if (!(envp = kcalloc(20, sizeof(char *), GFP_KERNEL)))
107		return -ENOMEM;
108	if (!(buf = kzalloc(256, GFP_KERNEL))) {
109		kfree(envp);
110		return -ENOMEM;
111	}
112
113	/* FIXME: if there are actual users of this, it should be
114	 * integrated into the driver core and use the usual infrastructure
115	 * like sysfs and uevents
116	 */
117	argv[0] = "/sbin/pnpbios";
118	argv[1] = "dock";
119	argv[2] = NULL;
120
121	/* minimal command environment */
122	envp[i++] = "HOME=/";
123	envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
124
125#ifdef	DEBUG
126	/* hint that policy agent should enter no-stdout debug mode */
127	envp[i++] = "DEBUG=kernel";
128#endif
129	/* extensible set of named bus-specific parameters,
130	 * supporting multiple driver selection algorithms.
131	 */
132	scratch = buf;
133
134	/* action:  add, remove */
135	envp[i++] = scratch;
136	scratch += sprintf(scratch, "ACTION=%s", dock ? "add" : "remove") + 1;
137
138	/* Report the ident for the dock */
139	envp[i++] = scratch;
140	scratch += sprintf(scratch, "DOCK=%x/%x/%x",
141			   info->location_id, info->serial, info->capabilities);
142	envp[i] = NULL;
143
144	value = call_usermodehelper(argv [0], argv, envp, UMH_WAIT_EXEC);
145	kfree(buf);
146	kfree(envp);
147	return 0;
148}
149
150/*
151 * Poll the PnP docking at regular intervals
152 */
153static int pnp_dock_thread(void *unused)
154{
155	static struct pnp_docking_station_info now;
156	int docked = -1, d = 0;
157
158	set_freezable();
159	while (1) {
160		int status;
161
162		/*
163		 * Poll every 2 seconds
164		 */
165		msleep_interruptible(2000);
166
167		if (try_to_freeze())
168			continue;
169
170		status = pnp_bios_dock_station_info(&now);
171
172		switch (status) {
173			/*
174			 * No dock to manage
175			 */
176		case PNP_FUNCTION_NOT_SUPPORTED:
177			complete_and_exit(&unload_sem, 0);
178		case PNP_SYSTEM_NOT_DOCKED:
179			d = 0;
180			break;
181		case PNP_SUCCESS:
182			d = 1;
183			break;
184		default:
185			pnpbios_print_status("pnp_dock_thread", status);
186			continue;
187		}
188		if (d != docked) {
189			if (pnp_dock_event(d, &now) == 0) {
190				docked = d;
191#if 0
192				printk(KERN_INFO
193				       "PnPBIOS: Docking station %stached\n",
194				       docked ? "at" : "de");
195#endif
196			}
197		}
198	}
199	complete_and_exit(&unload_sem, 0);
200}
201
202#endif				/* CONFIG_HOTPLUG */
203
204static int pnpbios_get_resources(struct pnp_dev *dev)
205{
206	u8 nodenum = dev->number;
207	struct pnp_bios_node *node;
208
209	if (!pnpbios_is_dynamic(dev))
210		return -EPERM;
211
212	pnp_dbg(&dev->dev, "get resources\n");
213	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
214	if (!node)
215		return -1;
216	if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
217		kfree(node);
218		return -ENODEV;
219	}
220	pnpbios_read_resources_from_node(dev, node);
221	dev->active = pnp_is_active(dev);
222	kfree(node);
223	return 0;
224}
225
226static int pnpbios_set_resources(struct pnp_dev *dev)
227{
228	u8 nodenum = dev->number;
229	struct pnp_bios_node *node;
230	int ret;
231
232	if (!pnpbios_is_dynamic(dev))
233		return -EPERM;
234
235	pnp_dbg(&dev->dev, "set resources\n");
236	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
237	if (!node)
238		return -1;
239	if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
240		kfree(node);
241		return -ENODEV;
242	}
243	if (pnpbios_write_resources_to_node(dev, node) < 0) {
244		kfree(node);
245		return -1;
246	}
247	ret = pnp_bios_set_dev_node(node->handle, (char)PNPMODE_DYNAMIC, node);
248	kfree(node);
249	if (ret > 0)
250		ret = -1;
251	return ret;
252}
253
254static void pnpbios_zero_data_stream(struct pnp_bios_node *node)
255{
256	unsigned char *p = (char *)node->data;
257	unsigned char *end = (char *)(node->data + node->size);
258	unsigned int len;
259	int i;
260
261	while ((char *)p < (char *)end) {
262		if (p[0] & 0x80) {	/* large tag */
263			len = (p[2] << 8) | p[1];
264			p += 3;
265		} else {
266			if (((p[0] >> 3) & 0x0f) == 0x0f)
267				return;
268			len = p[0] & 0x07;
269			p += 1;
270		}
271		for (i = 0; i < len; i++)
272			p[i] = 0;
273		p += len;
274	}
275	printk(KERN_ERR
276	       "PnPBIOS: Resource structure did not contain an end tag.\n");
277}
278
279static int pnpbios_disable_resources(struct pnp_dev *dev)
280{
281	struct pnp_bios_node *node;
282	u8 nodenum = dev->number;
283	int ret;
284
285	if (dev->flags & PNPBIOS_NO_DISABLE || !pnpbios_is_dynamic(dev))
286		return -EPERM;
287
288	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
289	if (!node)
290		return -ENOMEM;
291
292	if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
293		kfree(node);
294		return -ENODEV;
295	}
296	pnpbios_zero_data_stream(node);
297
298	ret = pnp_bios_set_dev_node(dev->number, (char)PNPMODE_DYNAMIC, node);
299	kfree(node);
300	if (ret > 0)
301		ret = -1;
302	return ret;
303}
304
305/* PnP Layer support */
306
307struct pnp_protocol pnpbios_protocol = {
308	.name = "Plug and Play BIOS",
309	.get = pnpbios_get_resources,
310	.set = pnpbios_set_resources,
311	.disable = pnpbios_disable_resources,
312};
313
314static int __init insert_device(struct pnp_bios_node *node)
315{
316	struct list_head *pos;
317	struct pnp_dev *dev;
318	char id[8];
319
320	/* check if the device is already added */
321	list_for_each(pos, &pnpbios_protocol.devices) {
322		dev = list_entry(pos, struct pnp_dev, protocol_list);
323		if (dev->number == node->handle)
324			return -1;
325	}
326
327	pnp_eisa_id_to_string(node->eisa_id & PNP_EISA_ID_MASK, id);
328	dev = pnp_alloc_dev(&pnpbios_protocol, node->handle, id);
329	if (!dev)
330		return -1;
331
332	pnpbios_parse_data_stream(dev, node);
333	dev->active = pnp_is_active(dev);
334	dev->flags = node->flags;
335	if (!(dev->flags & PNPBIOS_NO_CONFIG))
336		dev->capabilities |= PNP_CONFIGURABLE;
337	if (!(dev->flags & PNPBIOS_NO_DISABLE) && pnpbios_is_dynamic(dev))
338		dev->capabilities |= PNP_DISABLE;
339	dev->capabilities |= PNP_READ;
340	if (pnpbios_is_dynamic(dev))
341		dev->capabilities |= PNP_WRITE;
342	if (dev->flags & PNPBIOS_REMOVABLE)
343		dev->capabilities |= PNP_REMOVABLE;
344
345	/* clear out the damaged flags */
346	if (!dev->active)
347		pnp_init_resources(dev);
348
349	pnp_add_device(dev);
350	pnpbios_interface_attach_device(node);
351
352	return 0;
353}
354
355static void __init build_devlist(void)
356{
357	u8 nodenum;
358	unsigned int nodes_got = 0;
359	unsigned int devs = 0;
360	struct pnp_bios_node *node;
361
362	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
363	if (!node)
364		return;
365
366	for (nodenum = 0; nodenum < 0xff;) {
367		u8 thisnodenum = nodenum;
368		/* eventually we will want to use PNPMODE_STATIC here but for now
369		 * dynamic will help us catch buggy bioses to add to the blacklist.
370		 */
371		if (!pnpbios_dont_use_current_config) {
372			if (pnp_bios_get_dev_node
373			    (&nodenum, (char)PNPMODE_DYNAMIC, node))
374				break;
375		} else {
376			if (pnp_bios_get_dev_node
377			    (&nodenum, (char)PNPMODE_STATIC, node))
378				break;
379		}
380		nodes_got++;
381		if (insert_device(node) == 0)
382			devs++;
383		if (nodenum <= thisnodenum) {
384			printk(KERN_ERR
385			       "PnPBIOS: build_devlist: Node number 0x%x is out of sequence following node 0x%x. Aborting.\n",
386			       (unsigned int)nodenum,
387			       (unsigned int)thisnodenum);
388			break;
389		}
390	}
391	kfree(node);
392
393	printk(KERN_INFO
394	       "PnPBIOS: %i node%s reported by PnP BIOS; %i recorded by driver\n",
395	       nodes_got, nodes_got != 1 ? "s" : "", devs);
396}
397
398/*
399 *
400 * INIT AND EXIT
401 *
402 */
403
404static int pnpbios_disabled;
405int pnpbios_dont_use_current_config;
406
407static int __init pnpbios_setup(char *str)
408{
409	int invert;
410
411	while ((str != NULL) && (*str != '\0')) {
412		if (strncmp(str, "off", 3) == 0)
413			pnpbios_disabled = 1;
414		if (strncmp(str, "on", 2) == 0)
415			pnpbios_disabled = 0;
416		invert = (strncmp(str, "no-", 3) == 0);
417		if (invert)
418			str += 3;
419		if (strncmp(str, "curr", 4) == 0)
420			pnpbios_dont_use_current_config = invert;
421		str = strchr(str, ',');
422		if (str != NULL)
423			str += strspn(str, ", \t");
424	}
425
426	return 1;
427}
428
429__setup("pnpbios=", pnpbios_setup);
430
431/* PnP BIOS signature: "$PnP" */
432#define PNP_SIGNATURE   (('$' << 0) + ('P' << 8) + ('n' << 16) + ('P' << 24))
433
434static int __init pnpbios_probe_system(void)
435{
436	union pnp_bios_install_struct *check;
437	u8 sum;
438	int length, i;
439
440	printk(KERN_INFO "PnPBIOS: Scanning system for PnP BIOS support...\n");
441
442	/*
443	 * Search the defined area (0xf0000-0xffff0) for a valid PnP BIOS
444	 * structure and, if one is found, sets up the selectors and
445	 * entry points
446	 */
447	for (check = (union pnp_bios_install_struct *)__va(0xf0000);
448	     check < (union pnp_bios_install_struct *)__va(0xffff0);
449	     check = (void *)check + 16) {
450		if (check->fields.signature != PNP_SIGNATURE)
451			continue;
452		printk(KERN_INFO
453		       "PnPBIOS: Found PnP BIOS installation structure at 0x%p\n",
454		       check);
455		length = check->fields.length;
456		if (!length) {
457			printk(KERN_ERR
458			       "PnPBIOS: installation structure is invalid, skipping\n");
459			continue;
460		}
461		for (sum = 0, i = 0; i < length; i++)
462			sum += check->chars[i];
463		if (sum) {
464			printk(KERN_ERR
465			       "PnPBIOS: installation structure is corrupted, skipping\n");
466			continue;
467		}
468		if (check->fields.version < 0x10) {
469			printk(KERN_WARNING
470			       "PnPBIOS: PnP BIOS version %d.%d is not supported\n",
471			       check->fields.version >> 4,
472			       check->fields.version & 15);
473			continue;
474		}
475		printk(KERN_INFO
476		       "PnPBIOS: PnP BIOS version %d.%d, entry 0x%x:0x%x, dseg 0x%x\n",
477		       check->fields.version >> 4, check->fields.version & 15,
478		       check->fields.pm16cseg, check->fields.pm16offset,
479		       check->fields.pm16dseg);
480		pnp_bios_install = check;
481		return 1;
482	}
483
484	printk(KERN_INFO "PnPBIOS: PnP BIOS support was not detected.\n");
485	return 0;
486}
487
488static int __init exploding_pnp_bios(const struct dmi_system_id *d)
489{
490	printk(KERN_WARNING "%s detected. Disabling PnPBIOS\n", d->ident);
491	return 0;
492}
493
494static struct dmi_system_id pnpbios_dmi_table[] __initdata = {
495	{			/* PnPBIOS GPF on boot */
496	 .callback = exploding_pnp_bios,
497	 .ident = "Higraded P14H",
498	 .matches = {
499		     DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
500		     DMI_MATCH(DMI_BIOS_VERSION, "07.00T"),
501		     DMI_MATCH(DMI_SYS_VENDOR, "Higraded"),
502		     DMI_MATCH(DMI_PRODUCT_NAME, "P14H"),
503		     },
504	 },
505	{			/* PnPBIOS GPF on boot */
506	 .callback = exploding_pnp_bios,
507	 .ident = "ASUS P4P800",
508	 .matches = {
509		     DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc."),
510		     DMI_MATCH(DMI_BOARD_NAME, "P4P800"),
511		     },
512	 },
513	{}
514};
515
516static int __init pnpbios_init(void)
517{
518	int ret;
519
520#if defined(CONFIG_PPC)
521	if (check_legacy_ioport(PNPBIOS_BASE))
522		return -ENODEV;
523#endif
524	if (pnpbios_disabled || dmi_check_system(pnpbios_dmi_table) ||
525	    paravirt_enabled()) {
526		printk(KERN_INFO "PnPBIOS: Disabled\n");
527		return -ENODEV;
528	}
529#ifdef CONFIG_PNPACPI
530	if (!acpi_disabled && !pnpacpi_disabled) {
531		pnpbios_disabled = 1;
532		printk(KERN_INFO "PnPBIOS: Disabled by ACPI PNP\n");
533		return -ENODEV;
534	}
535#endif				/* CONFIG_ACPI */
536
537	/* scan the system for pnpbios support */
538	if (!pnpbios_probe_system())
539		return -ENODEV;
540
541	/* make preparations for bios calls */
542	pnpbios_calls_init(pnp_bios_install);
543
544	/* read the node info */
545	ret = pnp_bios_dev_node_info(&node_info);
546	if (ret) {
547		printk(KERN_ERR
548		       "PnPBIOS: Unable to get node info.  Aborting.\n");
549		return ret;
550	}
551
552	/* register with the pnp layer */
553	ret = pnp_register_protocol(&pnpbios_protocol);
554	if (ret) {
555		printk(KERN_ERR
556		       "PnPBIOS: Unable to register driver.  Aborting.\n");
557		return ret;
558	}
559
560	/* start the proc interface */
561	ret = pnpbios_proc_init();
562	if (ret)
563		printk(KERN_ERR "PnPBIOS: Failed to create proc interface.\n");
564
565	/* scan for pnpbios devices */
566	build_devlist();
567
568	pnp_platform_devices = 1;
569	return 0;
570}
571
572fs_initcall(pnpbios_init);
573
574static int __init pnpbios_thread_init(void)
575{
576#if defined(CONFIG_PPC)
577	if (check_legacy_ioport(PNPBIOS_BASE))
578		return 0;
579#endif
580	if (pnpbios_disabled)
581		return 0;
582#ifdef CONFIG_HOTPLUG
583	{
584		struct task_struct *task;
585		init_completion(&unload_sem);
586		task = kthread_run(pnp_dock_thread, NULL, "kpnpbiosd");
587		if (IS_ERR(task))
588			return PTR_ERR(task);
589	}
590#endif
591	return 0;
592}
593
594/* Start the kernel thread later: */
595module_init(pnpbios_thread_init);
596
597EXPORT_SYMBOL(pnpbios_protocol);
598