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/kmod.h>
15 #include <linux/completion.h>
16 #include <linux/spinlock.h>
17
18 #include <asm/page.h>
19 #include <asm/desc.h>
20 #include <asm/byteorder.h>
21
22 #include "pnpbios.h"
23
24 static struct {
25 u16 offset;
26 u16 segment;
27 } pnp_bios_callpoint;
28
29 /*
30 * These are some opcodes for a "static asmlinkage"
31 * As this code is *not* executed inside the linux kernel segment, but in a
32 * alias at offset 0, we need a far return that can not be compiled by
33 * default (please, prove me wrong! this is *really* ugly!)
34 * This is the only way to get the bios to return into the kernel code,
35 * because the bios code runs in 16 bit protected mode and therefore can only
36 * return to the caller if the call is within the first 64kB, and the linux
37 * kernel begins at offset 3GB...
38 */
39
40 asmlinkage void pnp_bios_callfunc(void);
41
42 __asm__(".text \n"
43 __ALIGN_STR "\n"
44 "pnp_bios_callfunc:\n"
45 " pushl %edx \n"
46 " pushl %ecx \n"
47 " pushl %ebx \n"
48 " pushl %eax \n"
49 " lcallw *pnp_bios_callpoint\n"
50 " addl $16, %esp \n"
51 " lret \n"
52 ".previous \n");
53
54 #define Q2_SET_SEL(cpu, selname, address, size) \
55 do { \
56 struct desc_struct *gdt = get_cpu_gdt_table((cpu)); \
57 set_desc_base(&gdt[(selname) >> 3], (u32)(address)); \
58 set_desc_limit(&gdt[(selname) >> 3], (size) - 1); \
59 } while(0)
60
61 static struct desc_struct bad_bios_desc = GDT_ENTRY_INIT(0x4092,
62 (unsigned long)__va(0x400UL), PAGE_SIZE - 0x400 - 1);
63
64 /*
65 * At some point we want to use this stack frame pointer to unwind
66 * after PnP BIOS oopses.
67 */
68
69 u32 pnp_bios_fault_esp;
70 u32 pnp_bios_fault_eip;
71 u32 pnp_bios_is_utter_crap = 0;
72
73 static spinlock_t pnp_bios_lock;
74
75 /*
76 * Support Functions
77 */
78
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)79 static inline u16 call_pnp_bios(u16 func, u16 arg1, u16 arg2, u16 arg3,
80 u16 arg4, u16 arg5, u16 arg6, u16 arg7,
81 void *ts1_base, u32 ts1_size,
82 void *ts2_base, u32 ts2_size)
83 {
84 unsigned long flags;
85 u16 status;
86 struct desc_struct save_desc_40;
87 int cpu;
88
89 /*
90 * PnP BIOSes are generally not terribly re-entrant.
91 * Also, don't rely on them to save everything correctly.
92 */
93 if (pnp_bios_is_utter_crap)
94 return PNP_FUNCTION_NOT_SUPPORTED;
95
96 cpu = get_cpu();
97 save_desc_40 = get_cpu_gdt_table(cpu)[0x40 / 8];
98 get_cpu_gdt_table(cpu)[0x40 / 8] = bad_bios_desc;
99
100 /* On some boxes IRQ's during PnP BIOS calls are deadly. */
101 spin_lock_irqsave(&pnp_bios_lock, flags);
102
103 /* The lock prevents us bouncing CPU here */
104 if (ts1_size)
105 Q2_SET_SEL(smp_processor_id(), PNP_TS1, ts1_base, ts1_size);
106 if (ts2_size)
107 Q2_SET_SEL(smp_processor_id(), PNP_TS2, ts2_base, ts2_size);
108
109 __asm__ __volatile__("pushl %%ebp\n\t"
110 "pushl %%edi\n\t"
111 "pushl %%esi\n\t"
112 "pushl %%ds\n\t"
113 "pushl %%es\n\t"
114 "pushl %%fs\n\t"
115 "pushl %%gs\n\t"
116 "pushfl\n\t"
117 "movl %%esp, pnp_bios_fault_esp\n\t"
118 "movl $1f, pnp_bios_fault_eip\n\t"
119 "lcall %5,%6\n\t"
120 "1:popfl\n\t"
121 "popl %%gs\n\t"
122 "popl %%fs\n\t"
123 "popl %%es\n\t"
124 "popl %%ds\n\t"
125 "popl %%esi\n\t"
126 "popl %%edi\n\t"
127 "popl %%ebp\n\t":"=a"(status)
128 :"0"((func) | (((u32) arg1) << 16)),
129 "b"((arg2) | (((u32) arg3) << 16)),
130 "c"((arg4) | (((u32) arg5) << 16)),
131 "d"((arg6) | (((u32) arg7) << 16)),
132 "i"(PNP_CS32), "i"(0)
133 :"memory");
134 spin_unlock_irqrestore(&pnp_bios_lock, flags);
135
136 get_cpu_gdt_table(cpu)[0x40 / 8] = save_desc_40;
137 put_cpu();
138
139 /* If we get here and this is set then the PnP BIOS faulted on us. */
140 if (pnp_bios_is_utter_crap) {
141 printk(KERN_ERR
142 "PnPBIOS: Warning! Your PnP BIOS caused a fatal error. Attempting to continue\n");
143 printk(KERN_ERR
144 "PnPBIOS: You may need to reboot with the \"pnpbios=off\" option to operate stably\n");
145 printk(KERN_ERR
146 "PnPBIOS: Check with your vendor for an updated BIOS\n");
147 }
148
149 return status;
150 }
151
pnpbios_print_status(const char * module,u16 status)152 void pnpbios_print_status(const char *module, u16 status)
153 {
154 switch (status) {
155 case PNP_SUCCESS:
156 printk(KERN_ERR "PnPBIOS: %s: function successful\n", module);
157 break;
158 case PNP_NOT_SET_STATICALLY:
159 printk(KERN_ERR "PnPBIOS: %s: unable to set static resources\n",
160 module);
161 break;
162 case PNP_UNKNOWN_FUNCTION:
163 printk(KERN_ERR "PnPBIOS: %s: invalid function number passed\n",
164 module);
165 break;
166 case PNP_FUNCTION_NOT_SUPPORTED:
167 printk(KERN_ERR
168 "PnPBIOS: %s: function not supported on this system\n",
169 module);
170 break;
171 case PNP_INVALID_HANDLE:
172 printk(KERN_ERR "PnPBIOS: %s: invalid handle\n", module);
173 break;
174 case PNP_BAD_PARAMETER:
175 printk(KERN_ERR "PnPBIOS: %s: invalid parameters were passed\n",
176 module);
177 break;
178 case PNP_SET_FAILED:
179 printk(KERN_ERR "PnPBIOS: %s: unable to set resources\n",
180 module);
181 break;
182 case PNP_EVENTS_NOT_PENDING:
183 printk(KERN_ERR "PnPBIOS: %s: no events are pending\n", module);
184 break;
185 case PNP_SYSTEM_NOT_DOCKED:
186 printk(KERN_ERR "PnPBIOS: %s: the system is not docked\n",
187 module);
188 break;
189 case PNP_NO_ISA_PNP_CARDS:
190 printk(KERN_ERR
191 "PnPBIOS: %s: no isapnp cards are installed on this system\n",
192 module);
193 break;
194 case PNP_UNABLE_TO_DETERMINE_DOCK_CAPABILITIES:
195 printk(KERN_ERR
196 "PnPBIOS: %s: cannot determine the capabilities of the docking station\n",
197 module);
198 break;
199 case PNP_CONFIG_CHANGE_FAILED_NO_BATTERY:
200 printk(KERN_ERR
201 "PnPBIOS: %s: unable to undock, the system does not have a battery\n",
202 module);
203 break;
204 case PNP_CONFIG_CHANGE_FAILED_RESOURCE_CONFLICT:
205 printk(KERN_ERR
206 "PnPBIOS: %s: could not dock due to resource conflicts\n",
207 module);
208 break;
209 case PNP_BUFFER_TOO_SMALL:
210 printk(KERN_ERR "PnPBIOS: %s: the buffer passed is too small\n",
211 module);
212 break;
213 case PNP_USE_ESCD_SUPPORT:
214 printk(KERN_ERR "PnPBIOS: %s: use ESCD instead\n", module);
215 break;
216 case PNP_MESSAGE_NOT_SUPPORTED:
217 printk(KERN_ERR "PnPBIOS: %s: the message is unsupported\n",
218 module);
219 break;
220 case PNP_HARDWARE_ERROR:
221 printk(KERN_ERR "PnPBIOS: %s: a hardware failure has occurred\n",
222 module);
223 break;
224 default:
225 printk(KERN_ERR "PnPBIOS: %s: unexpected status 0x%x\n", module,
226 status);
227 break;
228 }
229 }
230
231 /*
232 * PnP BIOS Low Level Calls
233 */
234
235 #define PNP_GET_NUM_SYS_DEV_NODES 0x00
236 #define PNP_GET_SYS_DEV_NODE 0x01
237 #define PNP_SET_SYS_DEV_NODE 0x02
238 #define PNP_GET_EVENT 0x03
239 #define PNP_SEND_MESSAGE 0x04
240 #define PNP_GET_DOCKING_STATION_INFORMATION 0x05
241 #define PNP_SET_STATIC_ALLOCED_RES_INFO 0x09
242 #define PNP_GET_STATIC_ALLOCED_RES_INFO 0x0a
243 #define PNP_GET_APM_ID_TABLE 0x0b
244 #define PNP_GET_PNP_ISA_CONFIG_STRUC 0x40
245 #define PNP_GET_ESCD_INFO 0x41
246 #define PNP_READ_ESCD 0x42
247 #define PNP_WRITE_ESCD 0x43
248
249 /*
250 * Call PnP BIOS with function 0x00, "get number of system device nodes"
251 */
__pnp_bios_dev_node_info(struct pnp_dev_node_info * data)252 static int __pnp_bios_dev_node_info(struct pnp_dev_node_info *data)
253 {
254 u16 status;
255
256 if (!pnp_bios_present())
257 return PNP_FUNCTION_NOT_SUPPORTED;
258 status = call_pnp_bios(PNP_GET_NUM_SYS_DEV_NODES, 0, PNP_TS1, 2,
259 PNP_TS1, PNP_DS, 0, 0, data,
260 sizeof(struct pnp_dev_node_info), NULL, 0);
261 data->no_nodes &= 0xff;
262 return status;
263 }
264
pnp_bios_dev_node_info(struct pnp_dev_node_info * data)265 int pnp_bios_dev_node_info(struct pnp_dev_node_info *data)
266 {
267 int status = __pnp_bios_dev_node_info(data);
268
269 if (status)
270 pnpbios_print_status("dev_node_info", status);
271 return status;
272 }
273
274 /*
275 * Note that some PnP BIOSes (e.g., on Sony Vaio laptops) die a horrible
276 * death if they are asked to access the "current" configuration.
277 * Therefore, if it's a matter of indifference, it's better to call
278 * get_dev_node() and set_dev_node() with boot=1 rather than with boot=0.
279 */
280
281 /*
282 * Call PnP BIOS with function 0x01, "get system device node"
283 * Input: *nodenum = desired node,
284 * boot = whether to get nonvolatile boot (!=0)
285 * or volatile current (0) config
286 * Output: *nodenum=next node or 0xff if no more nodes
287 */
__pnp_bios_get_dev_node(u8 * nodenum,char boot,struct pnp_bios_node * data)288 static int __pnp_bios_get_dev_node(u8 *nodenum, char boot,
289 struct pnp_bios_node *data)
290 {
291 u16 status;
292 u16 tmp_nodenum;
293
294 if (!pnp_bios_present())
295 return PNP_FUNCTION_NOT_SUPPORTED;
296 if (!boot && pnpbios_dont_use_current_config)
297 return PNP_FUNCTION_NOT_SUPPORTED;
298 tmp_nodenum = *nodenum;
299 status = call_pnp_bios(PNP_GET_SYS_DEV_NODE, 0, PNP_TS1, 0, PNP_TS2,
300 boot ? 2 : 1, PNP_DS, 0, &tmp_nodenum,
301 sizeof(tmp_nodenum), data, 65536);
302 *nodenum = tmp_nodenum;
303 return status;
304 }
305
pnp_bios_get_dev_node(u8 * nodenum,char boot,struct pnp_bios_node * data)306 int pnp_bios_get_dev_node(u8 *nodenum, char boot, struct pnp_bios_node *data)
307 {
308 int status;
309
310 status = __pnp_bios_get_dev_node(nodenum, boot, data);
311 if (status)
312 pnpbios_print_status("get_dev_node", status);
313 return status;
314 }
315
316 /*
317 * Call PnP BIOS with function 0x02, "set system device node"
318 * Input: *nodenum = desired node,
319 * boot = whether to set nonvolatile boot (!=0)
320 * or volatile current (0) config
321 */
__pnp_bios_set_dev_node(u8 nodenum,char boot,struct pnp_bios_node * data)322 static int __pnp_bios_set_dev_node(u8 nodenum, char boot,
323 struct pnp_bios_node *data)
324 {
325 u16 status;
326
327 if (!pnp_bios_present())
328 return PNP_FUNCTION_NOT_SUPPORTED;
329 if (!boot && pnpbios_dont_use_current_config)
330 return PNP_FUNCTION_NOT_SUPPORTED;
331 status = call_pnp_bios(PNP_SET_SYS_DEV_NODE, nodenum, 0, PNP_TS1,
332 boot ? 2 : 1, PNP_DS, 0, 0, data, 65536, NULL,
333 0);
334 return status;
335 }
336
pnp_bios_set_dev_node(u8 nodenum,char boot,struct pnp_bios_node * data)337 int pnp_bios_set_dev_node(u8 nodenum, char boot, struct pnp_bios_node *data)
338 {
339 int status;
340
341 status = __pnp_bios_set_dev_node(nodenum, boot, data);
342 if (status) {
343 pnpbios_print_status("set_dev_node", status);
344 return status;
345 }
346 if (!boot) { /* Update devlist */
347 status = pnp_bios_get_dev_node(&nodenum, boot, data);
348 if (status)
349 return status;
350 }
351 return status;
352 }
353
354 /*
355 * Call PnP BIOS with function 0x05, "get docking station information"
356 */
pnp_bios_dock_station_info(struct pnp_docking_station_info * data)357 int pnp_bios_dock_station_info(struct pnp_docking_station_info *data)
358 {
359 u16 status;
360
361 if (!pnp_bios_present())
362 return PNP_FUNCTION_NOT_SUPPORTED;
363 status = call_pnp_bios(PNP_GET_DOCKING_STATION_INFORMATION, 0, PNP_TS1,
364 PNP_DS, 0, 0, 0, 0, data,
365 sizeof(struct pnp_docking_station_info), NULL,
366 0);
367 return status;
368 }
369
370 /*
371 * Call PnP BIOS with function 0x0a, "get statically allocated resource
372 * information"
373 */
__pnp_bios_get_stat_res(char * info)374 static int __pnp_bios_get_stat_res(char *info)
375 {
376 u16 status;
377
378 if (!pnp_bios_present())
379 return PNP_FUNCTION_NOT_SUPPORTED;
380 status = call_pnp_bios(PNP_GET_STATIC_ALLOCED_RES_INFO, 0, PNP_TS1,
381 PNP_DS, 0, 0, 0, 0, info, 65536, NULL, 0);
382 return status;
383 }
384
pnp_bios_get_stat_res(char * info)385 int pnp_bios_get_stat_res(char *info)
386 {
387 int status;
388
389 status = __pnp_bios_get_stat_res(info);
390 if (status)
391 pnpbios_print_status("get_stat_res", status);
392 return status;
393 }
394
395 /*
396 * Call PnP BIOS with function 0x40, "get isa pnp configuration structure"
397 */
__pnp_bios_isapnp_config(struct pnp_isa_config_struc * data)398 static int __pnp_bios_isapnp_config(struct pnp_isa_config_struc *data)
399 {
400 u16 status;
401
402 if (!pnp_bios_present())
403 return PNP_FUNCTION_NOT_SUPPORTED;
404 status = call_pnp_bios(PNP_GET_PNP_ISA_CONFIG_STRUC, 0, PNP_TS1, PNP_DS,
405 0, 0, 0, 0, data,
406 sizeof(struct pnp_isa_config_struc), NULL, 0);
407 return status;
408 }
409
pnp_bios_isapnp_config(struct pnp_isa_config_struc * data)410 int pnp_bios_isapnp_config(struct pnp_isa_config_struc *data)
411 {
412 int status;
413
414 status = __pnp_bios_isapnp_config(data);
415 if (status)
416 pnpbios_print_status("isapnp_config", status);
417 return status;
418 }
419
420 /*
421 * Call PnP BIOS with function 0x41, "get ESCD info"
422 */
__pnp_bios_escd_info(struct escd_info_struc * data)423 static int __pnp_bios_escd_info(struct escd_info_struc *data)
424 {
425 u16 status;
426
427 if (!pnp_bios_present())
428 return ESCD_FUNCTION_NOT_SUPPORTED;
429 status = call_pnp_bios(PNP_GET_ESCD_INFO, 0, PNP_TS1, 2, PNP_TS1, 4,
430 PNP_TS1, PNP_DS, data,
431 sizeof(struct escd_info_struc), NULL, 0);
432 return status;
433 }
434
pnp_bios_escd_info(struct escd_info_struc * data)435 int pnp_bios_escd_info(struct escd_info_struc *data)
436 {
437 int status;
438
439 status = __pnp_bios_escd_info(data);
440 if (status)
441 pnpbios_print_status("escd_info", status);
442 return status;
443 }
444
445 /*
446 * Call PnP BIOS function 0x42, "read ESCD"
447 * nvram_base is determined by calling escd_info
448 */
__pnp_bios_read_escd(char * data,u32 nvram_base)449 static int __pnp_bios_read_escd(char *data, u32 nvram_base)
450 {
451 u16 status;
452
453 if (!pnp_bios_present())
454 return ESCD_FUNCTION_NOT_SUPPORTED;
455 status = call_pnp_bios(PNP_READ_ESCD, 0, PNP_TS1, PNP_TS2, PNP_DS, 0, 0,
456 0, data, 65536, __va(nvram_base), 65536);
457 return status;
458 }
459
pnp_bios_read_escd(char * data,u32 nvram_base)460 int pnp_bios_read_escd(char *data, u32 nvram_base)
461 {
462 int status;
463
464 status = __pnp_bios_read_escd(data, nvram_base);
465 if (status)
466 pnpbios_print_status("read_escd", status);
467 return status;
468 }
469
pnpbios_calls_init(union pnp_bios_install_struct * header)470 void pnpbios_calls_init(union pnp_bios_install_struct *header)
471 {
472 int i;
473
474 spin_lock_init(&pnp_bios_lock);
475 pnp_bios_callpoint.offset = header->fields.pm16offset;
476 pnp_bios_callpoint.segment = PNP_CS16;
477
478 for_each_possible_cpu(i) {
479 struct desc_struct *gdt = get_cpu_gdt_table(i);
480 if (!gdt)
481 continue;
482 set_desc_base(&gdt[GDT_ENTRY_PNPBIOS_CS32],
483 (unsigned long)&pnp_bios_callfunc);
484 set_desc_base(&gdt[GDT_ENTRY_PNPBIOS_CS16],
485 (unsigned long)__va(header->fields.pm16cseg));
486 set_desc_base(&gdt[GDT_ENTRY_PNPBIOS_DS],
487 (unsigned long)__va(header->fields.pm16dseg));
488 }
489 }
490