1 /*
2 * bioscalls.c - the lowlevel layer of the PnPBIOS driver
3 */
4
5 #include <linux/types.h>
6 #include <linux/module.h>
7 #include <linux/init.h>
8 #include <linux/linkage.h>
9 #include <linux/kernel.h>
10 #include <linux/device.h>
11 #include <linux/pnp.h>
12 #include <linux/mm.h>
13 #include <linux/smp.h>
14 #include <linux/slab.h>
15 #include <linux/kmod.h>
16 #include <linux/completion.h>
17 #include <linux/spinlock.h>
18
19 #include <asm/page.h>
20 #include <asm/desc.h>
21 #include <asm/system.h>
22 #include <asm/byteorder.h>
23
24 #include "pnpbios.h"
25
26 static struct {
27 u16 offset;
28 u16 segment;
29 } pnp_bios_callpoint;
30
31 /*
32 * These are some opcodes for a "static asmlinkage"
33 * As this code is *not* executed inside the linux kernel segment, but in a
34 * alias at offset 0, we need a far return that can not be compiled by
35 * default (please, prove me wrong! this is *really* ugly!)
36 * This is the only way to get the bios to return into the kernel code,
37 * because the bios code runs in 16 bit protected mode and therefore can only
38 * return to the caller if the call is within the first 64kB, and the linux
39 * kernel begins at offset 3GB...
40 */
41
42 asmlinkage void pnp_bios_callfunc(void);
43
44 __asm__(".text \n"
45 __ALIGN_STR "\n"
46 "pnp_bios_callfunc:\n"
47 " pushl %edx \n"
48 " pushl %ecx \n"
49 " pushl %ebx \n"
50 " pushl %eax \n"
51 " lcallw *pnp_bios_callpoint\n"
52 " addl $16, %esp \n"
53 " lret \n"
54 ".previous \n");
55
56 #define Q2_SET_SEL(cpu, selname, address, size) \
57 do { \
58 struct desc_struct *gdt = get_cpu_gdt_table((cpu)); \
59 set_base(gdt[(selname) >> 3], (u32)(address)); \
60 set_limit(gdt[(selname) >> 3], size); \
61 } while(0)
62
63 static struct desc_struct bad_bios_desc;
64
65 /*
66 * At some point we want to use this stack frame pointer to unwind
67 * after PnP BIOS oopses.
68 */
69
70 u32 pnp_bios_fault_esp;
71 u32 pnp_bios_fault_eip;
72 u32 pnp_bios_is_utter_crap = 0;
73
74 static spinlock_t pnp_bios_lock;
75
76 /*
77 * Support Functions
78 */
79
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)80 static inline u16 call_pnp_bios(u16 func, u16 arg1, u16 arg2, u16 arg3,
81 u16 arg4, u16 arg5, u16 arg6, u16 arg7,
82 void *ts1_base, u32 ts1_size,
83 void *ts2_base, u32 ts2_size)
84 {
85 unsigned long flags;
86 u16 status;
87 struct desc_struct save_desc_40;
88 int cpu;
89
90 /*
91 * PnP BIOSes are generally not terribly re-entrant.
92 * Also, don't rely on them to save everything correctly.
93 */
94 if (pnp_bios_is_utter_crap)
95 return PNP_FUNCTION_NOT_SUPPORTED;
96
97 cpu = get_cpu();
98 save_desc_40 = get_cpu_gdt_table(cpu)[0x40 / 8];
99 get_cpu_gdt_table(cpu)[0x40 / 8] = bad_bios_desc;
100
101 /* On some boxes IRQ's during PnP BIOS calls are deadly. */
102 spin_lock_irqsave(&pnp_bios_lock, flags);
103
104 /* The lock prevents us bouncing CPU here */
105 if (ts1_size)
106 Q2_SET_SEL(smp_processor_id(), PNP_TS1, ts1_base, ts1_size);
107 if (ts2_size)
108 Q2_SET_SEL(smp_processor_id(), PNP_TS2, ts2_base, ts2_size);
109
110 __asm__ __volatile__("pushl %%ebp\n\t"
111 "pushl %%edi\n\t"
112 "pushl %%esi\n\t"
113 "pushl %%ds\n\t"
114 "pushl %%es\n\t"
115 "pushl %%fs\n\t"
116 "pushl %%gs\n\t"
117 "pushfl\n\t"
118 "movl %%esp, pnp_bios_fault_esp\n\t"
119 "movl $1f, pnp_bios_fault_eip\n\t"
120 "lcall %5,%6\n\t"
121 "1:popfl\n\t"
122 "popl %%gs\n\t"
123 "popl %%fs\n\t"
124 "popl %%es\n\t"
125 "popl %%ds\n\t"
126 "popl %%esi\n\t"
127 "popl %%edi\n\t"
128 "popl %%ebp\n\t":"=a"(status)
129 :"0"((func) | (((u32) arg1) << 16)),
130 "b"((arg2) | (((u32) arg3) << 16)),
131 "c"((arg4) | (((u32) arg5) << 16)),
132 "d"((arg6) | (((u32) arg7) << 16)),
133 "i"(PNP_CS32), "i"(0)
134 :"memory");
135 spin_unlock_irqrestore(&pnp_bios_lock, flags);
136
137 get_cpu_gdt_table(cpu)[0x40 / 8] = save_desc_40;
138 put_cpu();
139
140 /* If we get here and this is set then the PnP BIOS faulted on us. */
141 if (pnp_bios_is_utter_crap) {
142 printk(KERN_ERR
143 "PnPBIOS: Warning! Your PnP BIOS caused a fatal error. Attempting to continue\n");
144 printk(KERN_ERR
145 "PnPBIOS: You may need to reboot with the \"pnpbios=off\" option to operate stably\n");
146 printk(KERN_ERR
147 "PnPBIOS: Check with your vendor for an updated BIOS\n");
148 }
149
150 return status;
151 }
152
pnpbios_print_status(const char * module,u16 status)153 void pnpbios_print_status(const char *module, u16 status)
154 {
155 switch (status) {
156 case PNP_SUCCESS:
157 printk(KERN_ERR "PnPBIOS: %s: function successful\n", module);
158 break;
159 case PNP_NOT_SET_STATICALLY:
160 printk(KERN_ERR "PnPBIOS: %s: unable to set static resources\n",
161 module);
162 break;
163 case PNP_UNKNOWN_FUNCTION:
164 printk(KERN_ERR "PnPBIOS: %s: invalid function number passed\n",
165 module);
166 break;
167 case PNP_FUNCTION_NOT_SUPPORTED:
168 printk(KERN_ERR
169 "PnPBIOS: %s: function not supported on this system\n",
170 module);
171 break;
172 case PNP_INVALID_HANDLE:
173 printk(KERN_ERR "PnPBIOS: %s: invalid handle\n", module);
174 break;
175 case PNP_BAD_PARAMETER:
176 printk(KERN_ERR "PnPBIOS: %s: invalid parameters were passed\n",
177 module);
178 break;
179 case PNP_SET_FAILED:
180 printk(KERN_ERR "PnPBIOS: %s: unable to set resources\n",
181 module);
182 break;
183 case PNP_EVENTS_NOT_PENDING:
184 printk(KERN_ERR "PnPBIOS: %s: no events are pending\n", module);
185 break;
186 case PNP_SYSTEM_NOT_DOCKED:
187 printk(KERN_ERR "PnPBIOS: %s: the system is not docked\n",
188 module);
189 break;
190 case PNP_NO_ISA_PNP_CARDS:
191 printk(KERN_ERR
192 "PnPBIOS: %s: no isapnp cards are installed on this system\n",
193 module);
194 break;
195 case PNP_UNABLE_TO_DETERMINE_DOCK_CAPABILITIES:
196 printk(KERN_ERR
197 "PnPBIOS: %s: cannot determine the capabilities of the docking station\n",
198 module);
199 break;
200 case PNP_CONFIG_CHANGE_FAILED_NO_BATTERY:
201 printk(KERN_ERR
202 "PnPBIOS: %s: unable to undock, the system does not have a battery\n",
203 module);
204 break;
205 case PNP_CONFIG_CHANGE_FAILED_RESOURCE_CONFLICT:
206 printk(KERN_ERR
207 "PnPBIOS: %s: could not dock due to resource conflicts\n",
208 module);
209 break;
210 case PNP_BUFFER_TOO_SMALL:
211 printk(KERN_ERR "PnPBIOS: %s: the buffer passed is too small\n",
212 module);
213 break;
214 case PNP_USE_ESCD_SUPPORT:
215 printk(KERN_ERR "PnPBIOS: %s: use ESCD instead\n", module);
216 break;
217 case PNP_MESSAGE_NOT_SUPPORTED:
218 printk(KERN_ERR "PnPBIOS: %s: the message is unsupported\n",
219 module);
220 break;
221 case PNP_HARDWARE_ERROR:
222 printk(KERN_ERR "PnPBIOS: %s: a hardware failure has occured\n",
223 module);
224 break;
225 default:
226 printk(KERN_ERR "PnPBIOS: %s: unexpected status 0x%x\n", module,
227 status);
228 break;
229 }
230 }
231
232 /*
233 * PnP BIOS Low Level Calls
234 */
235
236 #define PNP_GET_NUM_SYS_DEV_NODES 0x00
237 #define PNP_GET_SYS_DEV_NODE 0x01
238 #define PNP_SET_SYS_DEV_NODE 0x02
239 #define PNP_GET_EVENT 0x03
240 #define PNP_SEND_MESSAGE 0x04
241 #define PNP_GET_DOCKING_STATION_INFORMATION 0x05
242 #define PNP_SET_STATIC_ALLOCED_RES_INFO 0x09
243 #define PNP_GET_STATIC_ALLOCED_RES_INFO 0x0a
244 #define PNP_GET_APM_ID_TABLE 0x0b
245 #define PNP_GET_PNP_ISA_CONFIG_STRUC 0x40
246 #define PNP_GET_ESCD_INFO 0x41
247 #define PNP_READ_ESCD 0x42
248 #define PNP_WRITE_ESCD 0x43
249
250 /*
251 * Call PnP BIOS with function 0x00, "get number of system device nodes"
252 */
__pnp_bios_dev_node_info(struct pnp_dev_node_info * data)253 static int __pnp_bios_dev_node_info(struct pnp_dev_node_info *data)
254 {
255 u16 status;
256
257 if (!pnp_bios_present())
258 return PNP_FUNCTION_NOT_SUPPORTED;
259 status = call_pnp_bios(PNP_GET_NUM_SYS_DEV_NODES, 0, PNP_TS1, 2,
260 PNP_TS1, PNP_DS, 0, 0, data,
261 sizeof(struct pnp_dev_node_info), NULL, 0);
262 data->no_nodes &= 0xff;
263 return status;
264 }
265
pnp_bios_dev_node_info(struct pnp_dev_node_info * data)266 int pnp_bios_dev_node_info(struct pnp_dev_node_info *data)
267 {
268 int status = __pnp_bios_dev_node_info(data);
269
270 if (status)
271 pnpbios_print_status("dev_node_info", status);
272 return status;
273 }
274
275 /*
276 * Note that some PnP BIOSes (e.g., on Sony Vaio laptops) die a horrible
277 * death if they are asked to access the "current" configuration.
278 * Therefore, if it's a matter of indifference, it's better to call
279 * get_dev_node() and set_dev_node() with boot=1 rather than with boot=0.
280 */
281
282 /*
283 * Call PnP BIOS with function 0x01, "get system device node"
284 * Input: *nodenum = desired node,
285 * boot = whether to get nonvolatile boot (!=0)
286 * or volatile current (0) config
287 * Output: *nodenum=next node or 0xff if no more nodes
288 */
__pnp_bios_get_dev_node(u8 * nodenum,char boot,struct pnp_bios_node * data)289 static int __pnp_bios_get_dev_node(u8 *nodenum, char boot,
290 struct pnp_bios_node *data)
291 {
292 u16 status;
293 u16 tmp_nodenum;
294
295 if (!pnp_bios_present())
296 return PNP_FUNCTION_NOT_SUPPORTED;
297 if (!boot && pnpbios_dont_use_current_config)
298 return PNP_FUNCTION_NOT_SUPPORTED;
299 tmp_nodenum = *nodenum;
300 status = call_pnp_bios(PNP_GET_SYS_DEV_NODE, 0, PNP_TS1, 0, PNP_TS2,
301 boot ? 2 : 1, PNP_DS, 0, &tmp_nodenum,
302 sizeof(tmp_nodenum), data, 65536);
303 *nodenum = tmp_nodenum;
304 return status;
305 }
306
pnp_bios_get_dev_node(u8 * nodenum,char boot,struct pnp_bios_node * data)307 int pnp_bios_get_dev_node(u8 *nodenum, char boot, struct pnp_bios_node *data)
308 {
309 int status;
310
311 status = __pnp_bios_get_dev_node(nodenum, boot, data);
312 if (status)
313 pnpbios_print_status("get_dev_node", status);
314 return status;
315 }
316
317 /*
318 * Call PnP BIOS with function 0x02, "set system device node"
319 * Input: *nodenum = desired node,
320 * boot = whether to set nonvolatile boot (!=0)
321 * or volatile current (0) config
322 */
__pnp_bios_set_dev_node(u8 nodenum,char boot,struct pnp_bios_node * data)323 static int __pnp_bios_set_dev_node(u8 nodenum, char boot,
324 struct pnp_bios_node *data)
325 {
326 u16 status;
327
328 if (!pnp_bios_present())
329 return PNP_FUNCTION_NOT_SUPPORTED;
330 if (!boot && pnpbios_dont_use_current_config)
331 return PNP_FUNCTION_NOT_SUPPORTED;
332 status = call_pnp_bios(PNP_SET_SYS_DEV_NODE, nodenum, 0, PNP_TS1,
333 boot ? 2 : 1, PNP_DS, 0, 0, data, 65536, NULL,
334 0);
335 return status;
336 }
337
pnp_bios_set_dev_node(u8 nodenum,char boot,struct pnp_bios_node * data)338 int pnp_bios_set_dev_node(u8 nodenum, char boot, struct pnp_bios_node *data)
339 {
340 int status;
341
342 status = __pnp_bios_set_dev_node(nodenum, boot, data);
343 if (status) {
344 pnpbios_print_status("set_dev_node", status);
345 return status;
346 }
347 if (!boot) { /* Update devlist */
348 status = pnp_bios_get_dev_node(&nodenum, boot, data);
349 if (status)
350 return status;
351 }
352 return status;
353 }
354
355 /*
356 * Call PnP BIOS with function 0x05, "get docking station information"
357 */
pnp_bios_dock_station_info(struct pnp_docking_station_info * data)358 int pnp_bios_dock_station_info(struct pnp_docking_station_info *data)
359 {
360 u16 status;
361
362 if (!pnp_bios_present())
363 return PNP_FUNCTION_NOT_SUPPORTED;
364 status = call_pnp_bios(PNP_GET_DOCKING_STATION_INFORMATION, 0, PNP_TS1,
365 PNP_DS, 0, 0, 0, 0, data,
366 sizeof(struct pnp_docking_station_info), NULL,
367 0);
368 return status;
369 }
370
371 /*
372 * Call PnP BIOS with function 0x0a, "get statically allocated resource
373 * information"
374 */
__pnp_bios_get_stat_res(char * info)375 static int __pnp_bios_get_stat_res(char *info)
376 {
377 u16 status;
378
379 if (!pnp_bios_present())
380 return PNP_FUNCTION_NOT_SUPPORTED;
381 status = call_pnp_bios(PNP_GET_STATIC_ALLOCED_RES_INFO, 0, PNP_TS1,
382 PNP_DS, 0, 0, 0, 0, info, 65536, NULL, 0);
383 return status;
384 }
385
pnp_bios_get_stat_res(char * info)386 int pnp_bios_get_stat_res(char *info)
387 {
388 int status;
389
390 status = __pnp_bios_get_stat_res(info);
391 if (status)
392 pnpbios_print_status("get_stat_res", status);
393 return status;
394 }
395
396 /*
397 * Call PnP BIOS with function 0x40, "get isa pnp configuration structure"
398 */
__pnp_bios_isapnp_config(struct pnp_isa_config_struc * data)399 static int __pnp_bios_isapnp_config(struct pnp_isa_config_struc *data)
400 {
401 u16 status;
402
403 if (!pnp_bios_present())
404 return PNP_FUNCTION_NOT_SUPPORTED;
405 status = call_pnp_bios(PNP_GET_PNP_ISA_CONFIG_STRUC, 0, PNP_TS1, PNP_DS,
406 0, 0, 0, 0, data,
407 sizeof(struct pnp_isa_config_struc), NULL, 0);
408 return status;
409 }
410
pnp_bios_isapnp_config(struct pnp_isa_config_struc * data)411 int pnp_bios_isapnp_config(struct pnp_isa_config_struc *data)
412 {
413 int status;
414
415 status = __pnp_bios_isapnp_config(data);
416 if (status)
417 pnpbios_print_status("isapnp_config", status);
418 return status;
419 }
420
421 /*
422 * Call PnP BIOS with function 0x41, "get ESCD info"
423 */
__pnp_bios_escd_info(struct escd_info_struc * data)424 static int __pnp_bios_escd_info(struct escd_info_struc *data)
425 {
426 u16 status;
427
428 if (!pnp_bios_present())
429 return ESCD_FUNCTION_NOT_SUPPORTED;
430 status = call_pnp_bios(PNP_GET_ESCD_INFO, 0, PNP_TS1, 2, PNP_TS1, 4,
431 PNP_TS1, PNP_DS, data,
432 sizeof(struct escd_info_struc), NULL, 0);
433 return status;
434 }
435
pnp_bios_escd_info(struct escd_info_struc * data)436 int pnp_bios_escd_info(struct escd_info_struc *data)
437 {
438 int status;
439
440 status = __pnp_bios_escd_info(data);
441 if (status)
442 pnpbios_print_status("escd_info", status);
443 return status;
444 }
445
446 /*
447 * Call PnP BIOS function 0x42, "read ESCD"
448 * nvram_base is determined by calling escd_info
449 */
__pnp_bios_read_escd(char * data,u32 nvram_base)450 static int __pnp_bios_read_escd(char *data, u32 nvram_base)
451 {
452 u16 status;
453
454 if (!pnp_bios_present())
455 return ESCD_FUNCTION_NOT_SUPPORTED;
456 status = call_pnp_bios(PNP_READ_ESCD, 0, PNP_TS1, PNP_TS2, PNP_DS, 0, 0,
457 0, data, 65536, __va(nvram_base), 65536);
458 return status;
459 }
460
pnp_bios_read_escd(char * data,u32 nvram_base)461 int pnp_bios_read_escd(char *data, u32 nvram_base)
462 {
463 int status;
464
465 status = __pnp_bios_read_escd(data, nvram_base);
466 if (status)
467 pnpbios_print_status("read_escd", status);
468 return status;
469 }
470
pnpbios_calls_init(union pnp_bios_install_struct * header)471 void pnpbios_calls_init(union pnp_bios_install_struct *header)
472 {
473 int i;
474
475 spin_lock_init(&pnp_bios_lock);
476 pnp_bios_callpoint.offset = header->fields.pm16offset;
477 pnp_bios_callpoint.segment = PNP_CS16;
478
479 bad_bios_desc.a = 0;
480 bad_bios_desc.b = 0x00409200;
481
482 set_base(bad_bios_desc, __va((unsigned long)0x40 << 4));
483 _set_limit((char *)&bad_bios_desc, 4095 - (0x40 << 4));
484 for_each_possible_cpu(i) {
485 struct desc_struct *gdt = get_cpu_gdt_table(i);
486 if (!gdt)
487 continue;
488 set_base(gdt[GDT_ENTRY_PNPBIOS_CS32], &pnp_bios_callfunc);
489 set_base(gdt[GDT_ENTRY_PNPBIOS_CS16],
490 __va(header->fields.pm16cseg));
491 set_base(gdt[GDT_ENTRY_PNPBIOS_DS],
492 __va(header->fields.pm16dseg));
493 }
494 }
495