aboutsummaryrefslogtreecommitdiff
path: root/drivers/pnp/pnpbios/bioscalls.c
blob: 7e6b5a3b328177866ca2dbb15e7247510e95fd6e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
/*
 * bioscalls.c - the lowlevel layer of the PnPBIOS driver
 */

#include <linux/types.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/linkage.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/pnp.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/slab.h>
#include <linux/kmod.h>
#include <linux/completion.h>
#include <linux/spinlock.h>

#include <asm/page.h>
#include <asm/desc.h>
#include <asm/system.h>
#include <asm/byteorder.h>

#include "pnpbios.h"

static struct {
	u16 offset;
	u16 segment;
} pnp_bios_callpoint;

/*
 * These are some opcodes for a "static asmlinkage"
 * As this code is *not* executed inside the linux kernel segment, but in a
 * alias at offset 0, we need a far return that can not be compiled by
 * default (please, prove me wrong! this is *really* ugly!)
 * This is the only way to get the bios to return into the kernel code,
 * because the bios code runs in 16 bit protected mode and therefore can only
 * return to the caller if the call is within the first 64kB, and the linux
 * kernel begins at offset 3GB...
 */

asmlinkage void pnp_bios_callfunc(void);

__asm__(".text			\n"
	__ALIGN_STR "\n"
	"pnp_bios_callfunc:\n"
	"	pushl %edx	\n"
	"	pushl %ecx	\n"
	"	pushl %ebx	\n"
	"	pushl %eax	\n"
	"	lcallw *pnp_bios_callpoint\n"
	"	addl $16, %esp	\n"
	"	lret		\n"
	".previous		\n");

#define Q2_SET_SEL(cpu, selname, address, size) \
do { \
struct desc_struct *gdt = get_cpu_gdt_table((cpu)); \
set_base(gdt[(selname) >> 3], (u32)(address)); \
set_limit(gdt[(selname) >> 3], size); \
} while(0)

static struct desc_struct bad_bios_desc;

/*
 * At some point we want to use this stack frame pointer to unwind
 * after PnP BIOS oopses.
 */

u32 pnp_bios_fault_esp;
u32 pnp_bios_fault_eip;
u32 pnp_bios_is_utter_crap = 0;

static spinlock_t pnp_bios_lock;

/*
 * Support Functions
 */

static inline u16 call_pnp_bios(u16 func, u16 arg1, u16 arg2, u16 arg3,
				u16 arg4, u16 arg5, u16 arg6, u16 arg7,
				void *ts1_base, u32 ts1_size,
				void *ts2_base, u32 ts2_size)
{
	unsigned long flags;
	u16 status;
	struct desc_struct save_desc_40;
	int cpu;

	/*
	 * PnP BIOSes are generally not terribly re-entrant.
	 * Also, don't rely on them to save everything correctly.
	 */
	if (pnp_bios_is_utter_crap)
		return PNP_FUNCTION_NOT_SUPPORTED;

	cpu = get_cpu();
	save_desc_40 = get_cpu_gdt_table(cpu)[0x40 / 8];
	get_cpu_gdt_table(cpu)[0x40 / 8] = bad_bios_desc;

	/* On some boxes IRQ's during PnP BIOS calls are deadly.  */
	spin_lock_irqsave(&pnp_bios_lock, flags);

	/* The lock prevents us bouncing CPU here */
	if (ts1_size)
		Q2_SET_SEL(smp_processor_id(), PNP_TS1, ts1_base, ts1_size);
	if (ts2_size)
		Q2_SET_SEL(smp_processor_id(), PNP_TS2, ts2_base, ts2_size);

	__asm__ __volatile__("pushl %%ebp\n\t"
			     "pushl %%edi\n\t"
			     "pushl %%esi\n\t"
			     "pushl %%ds\n\t"
			     "pushl %%es\n\t"
			     "pushl %%fs\n\t"
			     "pushl %%gs\n\t"
			     "pushfl\n\t"
			     "movl %%esp, pnp_bios_fault_esp\n\t"
			     "movl $1f, pnp_bios_fault_eip\n\t"
			     "lcall %5,%6\n\t"
			     "1:popfl\n\t"
			     "popl %%gs\n\t"
			     "popl %%fs\n\t"
			     "popl %%es\n\t"
			     "popl %%ds\n\t"
			     "popl %%esi\n\t"
			     "popl %%edi\n\t"
			     "popl %%ebp\n\t":"=a"(status)
			     :"0"((func) | (((u32) arg1) << 16)),
			     "b"((arg2) | (((u32) arg3) << 16)),
			     "c"((arg4) | (((u32) arg5) << 16)),
			     "d"((arg6) | (((u32) arg7) << 16)),
			     "i"(PNP_CS32), "i"(0)
			     :"memory");
	spin_unlock_irqrestore(&pnp_bios_lock, flags);

	get_cpu_gdt_table(cpu)[0x40 / 8] = save_desc_40;
	put_cpu();

	/* If we get here and this is set then the PnP BIOS faulted on us. */
	if (pnp_bios_is_utter_crap) {
		printk(KERN_ERR
		       "PnPBIOS: Warning! Your PnP BIOS caused a fatal error. Attempting to continue\n");
		printk(KERN_ERR
		       "PnPBIOS: You may need to reboot with the \"pnpbios=off\" option to operate stably\n");
		printk(KERN_ERR
		       "PnPBIOS: Check with your vendor for an updated BIOS\n");
	}

	return status;
}

void pnpbios_print_status(const char *module, u16 status)
{
	switch (status) {
	case PNP_SUCCESS:
		printk(KERN_ERR "PnPBIOS: %s: function successful\n", module);
		break;
	case PNP_NOT_SET_STATICALLY:
		printk(KERN_ERR "PnPBIOS: %s: unable to set static resources\n",
		       module);
		break;
	case PNP_UNKNOWN_FUNCTION:
		printk(KERN_ERR "PnPBIOS: %s: invalid function number passed\n",
		       module);
		break;
	case PNP_FUNCTION_NOT_SUPPORTED:
		printk(KERN_ERR
		       "PnPBIOS: %s: function not supported on this system\n",
		       module);
		break;
	case PNP_INVALID_HANDLE:
		printk(KERN_ERR "PnPBIOS: %s: invalid handle\n", module);
		break;
	case PNP_BAD_PARAMETER:
		printk(KERN_ERR "PnPBIOS: %s: invalid parameters were passed\n",
		       module);
		break;
	case PNP_SET_FAILED:
		printk(KERN_ERR "PnPBIOS: %s: unable to set resources\n",
		       module);
		break;
	case PNP_EVENTS_NOT_PENDING:
		printk(KERN_ERR "PnPBIOS: %s: no events are pending\n", module);
		break;
	case PNP_SYSTEM_NOT_DOCKED:
		printk(KERN_ERR "PnPBIOS: %s: the system is not docked\n",
		       module);
		break;
	case PNP_NO_ISA_PNP_CARDS:
		printk(KERN_ERR
		       "PnPBIOS: %s: no isapnp cards are installed on this system\n",
		       module);
		break;
	case PNP_UNABLE_TO_DETERMINE_DOCK_CAPABILITIES:
		printk(KERN_ERR
		       "PnPBIOS: %s: cannot determine the capabilities of the docking station\n",
		       module);
		break;
	case PNP_CONFIG_CHANGE_FAILED_NO_BATTERY:
		printk(KERN_ERR
		       "PnPBIOS: %s: unable to undock, the system does not have a battery\n",
		       module);
		break;
	case PNP_CONFIG_CHANGE_FAILED_RESOURCE_CONFLICT:
		printk(KERN_ERR
		       "PnPBIOS: %s: could not dock due to resource conflicts\n",
		       module);
		break;
	case PNP_BUFFER_TOO_SMALL:
		printk(KERN_ERR "PnPBIOS: %s: the buffer passed is too small\n",
		       module);
		break;
	case PNP_USE_ESCD_SUPPORT:
		printk(KERN_ERR "PnPBIOS: %s: use ESCD instead\n", module);
		break;
	case PNP_MESSAGE_NOT_SUPPORTED:
		printk(KERN_ERR "PnPBIOS: %s: the message is unsupported\n",
		       module);
		break;
	case PNP_HARDWARE_ERROR:
		printk(KERN_ERR "PnPBIOS: %s: a hardware failure has occured\n",
		       module);
		break;
	default:
		printk(KERN_ERR "PnPBIOS: %s: unexpected status 0x%x\n", module,
		       status);
		break;
	}
}

/*
 * PnP BIOS Low Level Calls
 */

#define PNP_GET_NUM_SYS_DEV_NODES		0x00
#define PNP_GET_SYS_DEV_NODE			0x01
#define PNP_SET_SYS_DEV_NODE			0x02
#define PNP_GET_EVENT				0x03
#define PNP_SEND_MESSAGE			0x04
#define PNP_GET_DOCKING_STATION_INFORMATION	0x05
#define PNP_SET_STATIC_ALLOCED_RES_INFO		0x09
#define PNP_GET_STATIC_ALLOCED_RES_INFO		0x0a
#define PNP_GET_APM_ID_TABLE			0x0b
#define PNP_GET_PNP_ISA_CONFIG_STRUC		0x40
#define PNP_GET_ESCD_INFO			0x41
#define PNP_READ_ESCD				0x42
#define PNP_WRITE_ESCD				0x43

/*
 * Call PnP BIOS with function 0x00, "get number of system device nodes"
 */
static int __pnp_bios_dev_node_info(struct pnp_dev_node_info *data)
{
	u16 status;

	if (!pnp_bios_present())
		return PNP_FUNCTION_NOT_SUPPORTED;
	status = call_pnp_bios(PNP_GET_NUM_SYS_DEV_NODES, 0, PNP_TS1, 2,
			       PNP_TS1, PNP_DS, 0, 0, data,
			       sizeof(struct pnp_dev_node_info), NULL, 0);
	data->no_nodes &= 0xff;
	return status;
}

int pnp_bios_dev_node_info(struct pnp_dev_node_info *data)
{
	int status = __pnp_bios_dev_node_info(data);

	if (status)
		pnpbios_print_status("dev_node_info", status);
	return status;
}

/*
 * Note that some PnP BIOSes (e.g., on Sony Vaio laptops) die a horrible
 * death if they are asked to access the "current" configuration.
 * Therefore, if it's a matter of indifference, it's better to call
 * get_dev_node() and set_dev_node() with boot=1 rather than with boot=0.
 */

/* 
 * Call PnP BIOS with function 0x01, "get system device node"
 * Input: *nodenum = desired node,
 *        boot = whether to get nonvolatile boot (!=0)
 *               or volatile current (0) config
 * Output: *nodenum=next node or 0xff if no more nodes
 */
static int __pnp_bios_get_dev_node(u8 *nodenum, char boot,
				   struct pnp_bios_node *data)
{
	u16 status;
	u16 tmp_nodenum;

	if (!pnp_bios_present())
		return PNP_FUNCTION_NOT_SUPPORTED;
	if (!boot && pnpbios_dont_use_current_config)
		return PNP_FUNCTION_NOT_SUPPORTED;
	tmp_nodenum = *nodenum;
	status = call_pnp_bios(PNP_GET_SYS_DEV_NODE, 0, PNP_TS1, 0, PNP_TS2,
			       boot ? 2 : 1, PNP_DS, 0, &tmp_nodenum,
			       sizeof(tmp_nodenum), data, 65536);
	*nodenum = tmp_nodenum;
	return status;
}

int pnp_bios_get_dev_node(u8 *nodenum, char boot, struct pnp_bios_node *data)
{
	int status;

	status = __pnp_bios_get_dev_node(nodenum, boot, data);
	if (status)
		pnpbios_print_status("get_dev_node", status);
	return status;
}

/*
 * Call PnP BIOS with function 0x02, "set system device node"
 * Input: *nodenum = desired node, 
 *        boot = whether to set nonvolatile boot (!=0)
 *               or volatile current (0) config
 */
static int __pnp_bios_set_dev_node(u8 nodenum, char boot,
				   struct pnp_bios_node *data)
{
	u16 status;

	if (!pnp_bios_present())
		return PNP_FUNCTION_NOT_SUPPORTED;
	if (!boot && pnpbios_dont_use_current_config)
		return PNP_FUNCTION_NOT_SUPPORTED;
	status = call_pnp_bios(PNP_SET_SYS_DEV_NODE, nodenum, 0, PNP_TS1,
			       boot ? 2 : 1, PNP_DS, 0, 0, data, 65536, NULL,
			       0);
	return status;
}

int pnp_bios_set_dev_node(u8 nodenum, char boot, struct pnp_bios_node *data)
{
	int status;

	status = __pnp_bios_set_dev_node(nodenum, boot, data);
	if (status) {
		pnpbios_print_status("set_dev_node", status);
		return status;
	}
	if (!boot) {		/* Update devlist */
		status = pnp_bios_get_dev_node(&nodenum, boot, data);
		if (status)
			return status;
	}
	return status;
}

/*
 * Call PnP BIOS with function 0x05, "get docking station information"
 */
int pnp_bios_dock_station_info(struct pnp_docking_station_info *data)
{
	u16 status;

	if (!pnp_bios_present())
		return PNP_FUNCTION_NOT_SUPPORTED;
	status = call_pnp_bios(PNP_GET_DOCKING_STATION_INFORMATION, 0, PNP_TS1,
			       PNP_DS, 0, 0, 0, 0, data,
			       sizeof(struct pnp_docking_station_info), NULL,
			       0);
	return status;
}

/*
 * Call PnP BIOS with function 0x0a, "get statically allocated resource
 * information"
 */
static int __pnp_bios_get_stat_res(char *info)
{
	u16 status;

	if (!pnp_bios_present())
		return PNP_FUNCTION_NOT_SUPPORTED;
	status = call_pnp_bios(PNP_GET_STATIC_ALLOCED_RES_INFO, 0, PNP_TS1,
			       PNP_DS, 0, 0, 0, 0, info, 65536, NULL, 0);
	return status;
}

int pnp_bios_get_stat_res(char *info)
{
	int status;

	status = __pnp_bios_get_stat_res(info);
	if (status)
		pnpbios_print_status("get_stat_res", status);
	return status;
}

/*
 * Call PnP BIOS with function 0x40, "get isa pnp configuration structure"
 */
static int __pnp_bios_isapnp_config(struct pnp_isa_config_struc *data)
{
	u16 status;

	if (!pnp_bios_present())
		return PNP_FUNCTION_NOT_SUPPORTED;
	status = call_pnp_bios(PNP_GET_PNP_ISA_CONFIG_STRUC, 0, PNP_TS1, PNP_DS,
			       0, 0, 0, 0, data,
			       sizeof(struct pnp_isa_config_struc), NULL, 0);
	return status;
}

int pnp_bios_isapnp_config(struct pnp_isa_config_struc *data)
{
	int status;

	status = __pnp_bios_isapnp_config(data);
	if (status)
		pnpbios_print_status("isapnp_config", status);
	return status;
}

/*
 * Call PnP BIOS with function 0x41, "get ESCD info"
 */
static int __pnp_bios_escd_info(struct escd_info_struc *data)
{
	u16 status;

	if (!pnp_bios_present())
		return ESCD_FUNCTION_NOT_SUPPORTED;
	status = call_pnp_bios(PNP_GET_ESCD_INFO, 0, PNP_TS1, 2, PNP_TS1, 4,
			       PNP_TS1, PNP_DS, data,
			       sizeof(struct escd_info_struc), NULL, 0);
	return status;
}

int pnp_bios_escd_info(struct escd_info_struc *data)
{
	int status;

	status = __pnp_bios_escd_info(data);
	if (status)
		pnpbios_print_status("escd_info", status);
	return status;
}

/*
 * Call PnP BIOS function 0x42, "read ESCD"
 * nvram_base is determined by calling escd_info
 */
static int __pnp_bios_read_escd(char *data, u32 nvram_base)
{
	u16 status;

	if (!pnp_bios_present())
		return ESCD_FUNCTION_NOT_SUPPORTED;
	status = call_pnp_bios(PNP_READ_ESCD, 0, PNP_TS1, PNP_TS2, PNP_DS, 0, 0,
			       0, data, 65536, __va(nvram_base), 65536);
	return status;
}

int pnp_bios_read_escd(char *data, u32 nvram_base)
{
	int status;

	status = __pnp_bios_read_escd(data, nvram_base);
	if (status)
		pnpbios_print_status("read_escd", status);
	return status;
}

void pnpbios_calls_init(union pnp_bios_install_struct *header)
{
	int i;

	spin_lock_init(&pnp_bios_lock);
	pnp_bios_callpoint.offset = header->fields.pm16offset;
	pnp_bios_callpoint.segment = PNP_CS16;

	bad_bios_desc.a = 0;
	bad_bios_desc.b = 0x00409200;

	set_base(bad_bios_desc, __va((unsigned long)0x40 << 4));
	_set_limit((char *)&bad_bios_desc, 4095 - (0x40 << 4));
	for_each_possible_cpu(i) {
		struct desc_struct *gdt = get_cpu_gdt_table(i);
		if (!gdt)
			continue;
		set_base(gdt[GDT_ENTRY_PNPBIOS_CS32], &pnp_bios_callfunc);
		set_base(gdt[GDT_ENTRY_PNPBIOS_CS16],
			 __va(header->fields.pm16cseg));
		set_base(gdt[GDT_ENTRY_PNPBIOS_DS],
			 __va(header->fields.pm16dseg));
	}
}