drivers/pnp/pnpbios/bioscalls.c

   1 /*
   2  * bioscalls.c - the lowlevel layer of the PnPBIOS driver
   3  *
   4  */
   5
   6 #include <linux/types.h>
   7 #include <linux/module.h>
   8 #include <linux/init.h>
   9 #include <linux/linkage.h>
  10 #include <linux/kernel.h>
  11 #include <linux/pnpbios.h>
  12 #include <linux/device.h>
  13 #include <linux/pnp.h>
  14 #include <linux/mm.h>
  15 #include <linux/smp.h>
  16 #include <linux/slab.h>
  17 #include <linux/kmod.h>
  18 #include <linux/completion.h>
  19 #include <linux/spinlock.h>
  20
  21 #include <asm/page.h>
  22 #include <asm/desc.h>
  23 #include <asm/system.h>
  24 #include <asm/byteorder.h>
  25
  26 #include "pnpbios.h"
  27
  28 static struct {
  29         u16     offset;
  30         u16     segment;
  31 } pnp_bios_callpoint;
  32
  33
  34 /*
  35  * These are some opcodes for a "static asmlinkage"
  36  * As this code is *not* executed inside the linux kernel segment, but in a
  37  * alias at offset 0, we need a far return that can not be compiled by
  38  * default (please, prove me wrong! this is *really* ugly!)
  39  * This is the only way to get the bios to return into the kernel code,
  40  * because the bios code runs in 16 bit protected mode and therefore can only
  41  * return to the caller if the call is within the first 64kB, and the linux
  42  * kernel begins at offset 3GB...
  43  */
  44
  45 asmlinkage void pnp_bios_callfunc(void);
  46
  47 __asm__(
  48         ".text                  \n"
  49         __ALIGN_STR "\n"
  50         "pnp_bios_callfunc:\n"
  51         "       pushl %edx      \n"
  52         "       pushl %ecx      \n"
  53         "       pushl %ebx      \n"
  54         "       pushl %eax      \n"
  55         "       lcallw *pnp_bios_callpoint\n"
  56         "       addl $16, %esp  \n"
  57         "       lret            \n"
  58         ".previous              \n"
  59 );
  60
  61 #define Q_SET_SEL(cpu, selname, address, size) \
  62 do { \
  63 struct desc_struct *gdt = get_cpu_gdt_table((cpu)); \
  64 set_base(gdt[(selname) >> 3], __va((u32)(address))); \
  65 set_limit(gdt[(selname) >> 3], size); \
  66 } while(0)
  67
  68 #define Q2_SET_SEL(cpu, selname, address, size) \
  69 do { \
  70 struct desc_struct *gdt = get_cpu_gdt_table((cpu)); \
  71 set_base(gdt[(selname) >> 3], (u32)(address)); \
  72 set_limit(gdt[(selname) >> 3], size); \
  73 } while(0)
  74
  75 static struct desc_struct bad_bios_desc = { 0, 0x00409200 };
  76
  77 /*
  78  * At some point we want to use this stack frame pointer to unwind
  79  * after PnP BIOS oopses.
  80  */
  81
  82 u32 pnp_bios_fault_esp;
  83 u32 pnp_bios_fault_eip;
  84 u32 pnp_bios_is_utter_crap = 0;
  85
  86 static spinlock_t pnp_bios_lock;
  87
  88
  89 /*
  90  * Support Functions
  91  */
  92
  93 static inline u16 call_pnp_bios(u16 func, u16 arg1, u16 arg2, u16 arg3,
  94                                 u16 arg4, u16 arg5, u16 arg6, u16 arg7,
  95                                 void *ts1_base, u32 ts1_size,
  96                                 void *ts2_base, u32 ts2_size)
  97 {
  98         unsigned long flags;
  99         u16 status;
 100         struct desc_struct save_desc_40;
 101         int cpu;
 102
 103         /*
 104          * PnP BIOSes are generally not terribly re-entrant.
 105          * Also, don't rely on them to save everything correctly.
 106          */
 107         if(pnp_bios_is_utter_crap)
 108                 return PNP_FUNCTION_NOT_SUPPORTED;
 109
 110         cpu = get_cpu();
 111         save_desc_40 = get_cpu_gdt_table(cpu)[0x40 / 8];
 112         get_cpu_gdt_table(cpu)[0x40 / 8] = bad_bios_desc;
 113
 114         /* On some boxes IRQ's during PnP BIOS calls are deadly.  */
 115         spin_lock_irqsave(&pnp_bios_lock, flags);
 116
 117         /* The lock prevents us bouncing CPU here */
 118         if (ts1_size)
 119                 Q2_SET_SEL(smp_processor_id(), PNP_TS1, ts1_base, ts1_size);
 120         if (ts2_size)
 121                 Q2_SET_SEL(smp_processor_id(), PNP_TS2, ts2_base, ts2_size);
 122
 123         __asm__ __volatile__(
 124                 "pushl %%ebp\n\t"
 125                 "pushl %%edi\n\t"
 126                 "pushl %%esi\n\t"
 127                 "pushl %%ds\n\t"
 128                 "pushl %%es\n\t"
 129                 "pushl %%fs\n\t"
 130                 "pushl %%gs\n\t"
 131                 "pushfl\n\t"
 132                 "movl %%esp, pnp_bios_fault_esp\n\t"
 133                 "movl $1f, pnp_bios_fault_eip\n\t"
 134                 "lcall %5,%6\n\t"
 135                 "1:popfl\n\t"
 136                 "popl %%gs\n\t"
 137                 "popl %%fs\n\t"
 138                 "popl %%es\n\t"
 139                 "popl %%ds\n\t"
 140                 "popl %%esi\n\t"
 141                 "popl %%edi\n\t"
 142                 "popl %%ebp\n\t"
 143                 : "=a" (status)
 144                 : "0" ((func) | (((u32)arg1) << 16)),
 145                   "b" ((arg2) | (((u32)arg3) << 16)),
 146                   "c" ((arg4) | (((u32)arg5) << 16)),
 147                   "d" ((arg6) | (((u32)arg7) << 16)),
 148                   "i" (PNP_CS32),
 149                   "i" (0)
 150                 : "memory"
 151         );
 152         spin_unlock_irqrestore(&pnp_bios_lock, flags);
 153
 154         get_cpu_gdt_table(cpu)[0x40 / 8] = save_desc_40;
 155         put_cpu();
 156
 157         /* If we get here and this is set then the PnP BIOS faulted on us. */
 158         if(pnp_bios_is_utter_crap)
 159         {
 160                 printk(KERN_ERR "PnPBIOS: Warning! Your PnP BIOS caused a fatal error. Attempting to continue\n");
 161                 printk(KERN_ERR "PnPBIOS: You may need to reboot with the \"pnpbios=off\" option to operate stably\n");
 162                 printk(KERN_ERR "PnPBIOS: Check with your vendor for an updated BIOS\n");
 163         }
 164
 165         return status;
 166 }
 167
 168 void pnpbios_print_status(const char * module, u16 status)
 169 {
 170         switch(status) {
 171         case PNP_SUCCESS:
 172                 printk(KERN_ERR "PnPBIOS: %s: function successful\n", module);
 173                 break;
 174         case PNP_NOT_SET_STATICALLY:
 175                 printk(KERN_ERR "PnPBIOS: %s: unable to set static resources\n", module);
 176                 break;
 177         case PNP_UNKNOWN_FUNCTION:
 178                 printk(KERN_ERR "PnPBIOS: %s: invalid function number passed\n", module);
 179                 break;
 180         case PNP_FUNCTION_NOT_SUPPORTED:
 181                 printk(KERN_ERR "PnPBIOS: %s: function not supported on this system\n", module);
 182                 break;
 183         case PNP_INVALID_HANDLE:
 184                 printk(KERN_ERR "PnPBIOS: %s: invalid handle\n", module);
 185                 break;
 186         case PNP_BAD_PARAMETER:
 187                 printk(KERN_ERR "PnPBIOS: %s: invalid parameters were passed\n", module);
 188                 break;
 189         case PNP_SET_FAILED:
 190                 printk(KERN_ERR "PnPBIOS: %s: unable to set resources\n", module);
 191                 break;
 192         case PNP_EVENTS_NOT_PENDING:
 193                 printk(KERN_ERR "PnPBIOS: %s: no events are pending\n", module);
 194                 break;
 195         case PNP_SYSTEM_NOT_DOCKED:
 196                 printk(KERN_ERR "PnPBIOS: %s: the system is not docked\n", module);
 197                 break;
 198         case PNP_NO_ISA_PNP_CARDS:
 199                 printk(KERN_ERR "PnPBIOS: %s: no isapnp cards are installed on this system\n", module);
 200                 break;
 201         case PNP_UNABLE_TO_DETERMINE_DOCK_CAPABILITIES:
 202                 printk(KERN_ERR "PnPBIOS: %s: cannot determine the capabilities of the docking station\n", module);
 203                 break;
 204         case PNP_CONFIG_CHANGE_FAILED_NO_BATTERY:
 205                 printk(KERN_ERR "PnPBIOS: %s: unable to undock, the system does not have a battery\n", module);
 206                 break;
 207         case PNP_CONFIG_CHANGE_FAILED_RESOURCE_CONFLICT:
 208                 printk(KERN_ERR "PnPBIOS: %s: could not dock due to resource conflicts\n", module);
 209                 break;
 210         case PNP_BUFFER_TOO_SMALL:
 211                 printk(KERN_ERR "PnPBIOS: %s: the buffer passed is too small\n", 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", module);
 218                 break;
 219         case PNP_HARDWARE_ERROR:
 220                 printk(KERN_ERR "PnPBIOS: %s: a hardware failure has occured\n", module);
 221                 break;
 222         default:
 223                 printk(KERN_ERR "PnPBIOS: %s: unexpected status 0x%x\n", module, status);
 224                 break;
 225         }
 226 }
 227
 228
 229 /*
 230  * PnP BIOS Low Level Calls
 231  */
 232
 233 #define PNP_GET_NUM_SYS_DEV_NODES               0x00
 234 #define PNP_GET_SYS_DEV_NODE                    0x01
 235 #define PNP_SET_SYS_DEV_NODE                    0x02
 236 #define PNP_GET_EVENT                           0x03
 237 #define PNP_SEND_MESSAGE                        0x04
 238 #define PNP_GET_DOCKING_STATION_INFORMATION     0x05
 239 #define PNP_SET_STATIC_ALLOCED_RES_INFO         0x09
 240 #define PNP_GET_STATIC_ALLOCED_RES_INFO         0x0a
 241 #define PNP_GET_APM_ID_TABLE                    0x0b
 242 #define PNP_GET_PNP_ISA_CONFIG_STRUC            0x40
 243 #define PNP_GET_ESCD_INFO                       0x41
 244 #define PNP_READ_ESCD                           0x42
 245 #define PNP_WRITE_ESCD                          0x43
 246
 247 /*
 248  * Call PnP BIOS with function 0x00, "get number of system device nodes"
 249  */
 250 static int __pnp_bios_dev_node_info(struct pnp_dev_node_info *data)
 251 {
 252         u16 status;
 253         if (!pnp_bios_present())
 254                 return PNP_FUNCTION_NOT_SUPPORTED;
 255         status = call_pnp_bios(PNP_GET_NUM_SYS_DEV_NODES, 0, PNP_TS1, 2, PNP_TS1, PNP_DS, 0, 0,
 256                                data, sizeof(struct pnp_dev_node_info), NULL, 0);
 257         data->no_nodes &= 0xff;
 258         return status;
 259 }
 260
 261 int pnp_bios_dev_node_info(struct pnp_dev_node_info *data)
 262 {
 263         int status = __pnp_bios_dev_node_info( data );
 264         if ( status )
 265                 pnpbios_print_status( "dev_node_info", status );
 266         return status;
 267 }
 268
 269 /*
 270  * Note that some PnP BIOSes (e.g., on Sony Vaio laptops) die a horrible
 271  * death if they are asked to access the "current" configuration.
 272  * Therefore, if it's a matter of indifference, it's better to call
 273  * get_dev_node() and set_dev_node() with boot=1 rather than with boot=0.
 274  */
 275
 276 /*
 277  * Call PnP BIOS with function 0x01, "get system device node"
 278  * Input: *nodenum = desired node,
 279  *        boot = whether to get nonvolatile boot (!=0)
 280  *               or volatile current (0) config
 281  * Output: *nodenum=next node or 0xff if no more nodes
 282  */
 283 static int __pnp_bios_get_dev_node(u8 *nodenum, char boot, struct pnp_bios_node *data)
 284 {
 285         u16 status;
 286         if (!pnp_bios_present())
 287                 return PNP_FUNCTION_NOT_SUPPORTED;
 288         if ( !boot && pnpbios_dont_use_current_config )
 289                 return PNP_FUNCTION_NOT_SUPPORTED;
 290         status = call_pnp_bios(PNP_GET_SYS_DEV_NODE, 0, PNP_TS1, 0, PNP_TS2, boot ? 2 : 1, PNP_DS, 0,
 291                                nodenum, sizeof(char), data, 65536);
 292         return status;
 293 }
 294
 295 int pnp_bios_get_dev_node(u8 *nodenum, char boot, struct pnp_bios_node *data)
 296 {
 297         int status;
 298         status =  __pnp_bios_get_dev_node( nodenum, boot, data );
 299         if ( status )
 300                 pnpbios_print_status( "get_dev_node", status );
 301         return status;
 302 }
 303
 304
 305 /*
 306  * Call PnP BIOS with function 0x02, "set system device node"
 307  * Input: *nodenum = desired node,
 308  *        boot = whether to set nonvolatile boot (!=0)
 309  *               or volatile current (0) config
 310  */
 311 static int __pnp_bios_set_dev_node(u8 nodenum, char boot, struct pnp_bios_node *data)
 312 {
 313         u16 status;
 314         if (!pnp_bios_present())
 315                 return PNP_FUNCTION_NOT_SUPPORTED;
 316         if ( !boot && pnpbios_dont_use_current_config )
 317                 return PNP_FUNCTION_NOT_SUPPORTED;
 318         status = call_pnp_bios(PNP_SET_SYS_DEV_NODE, nodenum, 0, PNP_TS1, boot ? 2 : 1, PNP_DS, 0, 0,
 319                                data, 65536, NULL, 0);
 320         return status;
 321 }
 322
 323 int pnp_bios_set_dev_node(u8 nodenum, char boot, struct pnp_bios_node *data)
 324 {
 325         int status;
 326         status =  __pnp_bios_set_dev_node( nodenum, boot, data );
 327         if ( status ) {
 328                 pnpbios_print_status( "set_dev_node", status );
 329                 return status;
 330         }
 331         if ( !boot ) { /* Update devlist */
 332                 status =  pnp_bios_get_dev_node( &nodenum, boot, data );
 333                 if ( status )
 334                         return status;
 335         }
 336         return status;
 337 }
 338
 339 #if needed
 340 /*
 341  * Call PnP BIOS with function 0x03, "get event"
 342  */
 343 static int pnp_bios_get_event(u16 *event)
 344 {
 345         u16 status;
 346         if (!pnp_bios_present())
 347                 return PNP_FUNCTION_NOT_SUPPORTED;
 348         status = call_pnp_bios(PNP_GET_EVENT, 0, PNP_TS1, PNP_DS, 0, 0 ,0 ,0,
 349                                event, sizeof(u16), NULL, 0);
 350         return status;
 351 }
 352 #endif
 353
 354 #if needed
 355 /*
 356  * Call PnP BIOS with function 0x04, "send message"
 357  */
 358 static int pnp_bios_send_message(u16 message)
 359 {
 360         u16 status;
 361         if (!pnp_bios_present())
 362                 return PNP_FUNCTION_NOT_SUPPORTED;
 363         status = call_pnp_bios(PNP_SEND_MESSAGE, message, PNP_DS, 0, 0, 0, 0, 0, 0, 0, 0, 0);
 364         return status;
 365 }
 366 #endif
 367
 368 /*
 369  * Call PnP BIOS with function 0x05, "get docking station information"
 370  */
 371 int pnp_bios_dock_station_info(struct pnp_docking_station_info *data)
 372 {
 373         u16 status;
 374         if (!pnp_bios_present())
 375                 return PNP_FUNCTION_NOT_SUPPORTED;
 376         status = call_pnp_bios(PNP_GET_DOCKING_STATION_INFORMATION, 0, PNP_TS1, PNP_DS, 0, 0, 0, 0,
 377                                data, sizeof(struct pnp_docking_station_info), NULL, 0);
 378         return status;
 379 }
 380
 381 #if needed
 382 /*
 383  * Call PnP BIOS with function 0x09, "set statically allocated resource
 384  * information"
 385  */
 386 static int pnp_bios_set_stat_res(char *info)
 387 {
 388         u16 status;
 389         if (!pnp_bios_present())
 390                 return PNP_FUNCTION_NOT_SUPPORTED;
 391         status = call_pnp_bios(PNP_SET_STATIC_ALLOCED_RES_INFO, 0, PNP_TS1, PNP_DS, 0, 0, 0, 0,
 392                                info, *((u16 *) info), 0, 0);
 393         return status;
 394 }
 395 #endif
 396
 397 /*
 398  * Call PnP BIOS with function 0x0a, "get statically allocated resource
 399  * information"
 400  */
 401 static int __pnp_bios_get_stat_res(char *info)
 402 {
 403         u16 status;
 404         if (!pnp_bios_present())
 405                 return PNP_FUNCTION_NOT_SUPPORTED;
 406         status = call_pnp_bios(PNP_GET_STATIC_ALLOCED_RES_INFO, 0, PNP_TS1, PNP_DS, 0, 0, 0, 0,
 407                                info, 65536, NULL, 0);
 408         return status;
 409 }
 410
 411 int pnp_bios_get_stat_res(char *info)
 412 {
 413         int status;
 414         status = __pnp_bios_get_stat_res( info );
 415         if ( status )
 416                 pnpbios_print_status( "get_stat_res", status );
 417         return status;
 418 }
 419
 420 #if needed
 421 /*
 422  * Call PnP BIOS with function 0x0b, "get APM id table"
 423  */
 424 static int pnp_bios_apm_id_table(char *table, u16 *size)
 425 {
 426         u16 status;
 427         if (!pnp_bios_present())
 428                 return PNP_FUNCTION_NOT_SUPPORTED;
 429         status = call_pnp_bios(PNP_GET_APM_ID_TABLE, 0, PNP_TS2, 0, PNP_TS1, PNP_DS, 0, 0,
 430                                table, *size, size, sizeof(u16));
 431         return status;
 432 }
 433 #endif
 434
 435 /*
 436  * Call PnP BIOS with function 0x40, "get isa pnp configuration structure"
 437  */
 438 static int __pnp_bios_isapnp_config(struct pnp_isa_config_struc *data)
 439 {
 440         u16 status;
 441         if (!pnp_bios_present())
 442                 return PNP_FUNCTION_NOT_SUPPORTED;
 443         status = call_pnp_bios(PNP_GET_PNP_ISA_CONFIG_STRUC, 0, PNP_TS1, PNP_DS, 0, 0, 0, 0,
 444                                data, sizeof(struct pnp_isa_config_struc), NULL, 0);
 445         return status;
 446 }
 447
 448 int pnp_bios_isapnp_config(struct pnp_isa_config_struc *data)
 449 {
 450         int status;
 451         status = __pnp_bios_isapnp_config( data );
 452         if ( status )
 453                 pnpbios_print_status( "isapnp_config", status );
 454         return status;
 455 }
 456
 457 /*
 458  * Call PnP BIOS with function 0x41, "get ESCD info"
 459  */
 460 static int __pnp_bios_escd_info(struct escd_info_struc *data)
 461 {
 462         u16 status;
 463         if (!pnp_bios_present())
 464                 return ESCD_FUNCTION_NOT_SUPPORTED;
 465         status = call_pnp_bios(PNP_GET_ESCD_INFO, 0, PNP_TS1, 2, PNP_TS1, 4, PNP_TS1, PNP_DS,
 466                                data, sizeof(struct escd_info_struc), NULL, 0);
 467         return status;
 468 }
 469
 470 int pnp_bios_escd_info(struct escd_info_struc *data)
 471 {
 472         int status;
 473         status = __pnp_bios_escd_info( data );
 474         if ( status )
 475                 pnpbios_print_status( "escd_info", status );
 476         return status;
 477 }
 478
 479 /*
 480  * Call PnP BIOS function 0x42, "read ESCD"
 481  * nvram_base is determined by calling escd_info
 482  */
 483 static int __pnp_bios_read_escd(char *data, u32 nvram_base)
 484 {
 485         u16 status;
 486         if (!pnp_bios_present())
 487                 return ESCD_FUNCTION_NOT_SUPPORTED;
 488         status = call_pnp_bios(PNP_READ_ESCD, 0, PNP_TS1, PNP_TS2, PNP_DS, 0, 0, 0,
 489                                data, 65536, __va(nvram_base), 65536);
 490         return status;
 491 }
 492
 493 int pnp_bios_read_escd(char *data, u32 nvram_base)
 494 {
 495         int status;
 496         status = __pnp_bios_read_escd( data, nvram_base );
 497         if ( status )
 498                 pnpbios_print_status( "read_escd", status );
 499         return status;
 500 }
 501
 502 #if needed
 503 /*
 504  * Call PnP BIOS function 0x43, "write ESCD"
 505  */
 506 static int pnp_bios_write_escd(char *data, u32 nvram_base)
 507 {
 508         u16 status;
 509         if (!pnp_bios_present())
 510                 return ESCD_FUNCTION_NOT_SUPPORTED;
 511         status = call_pnp_bios(PNP_WRITE_ESCD, 0, PNP_TS1, PNP_TS2, PNP_DS, 0, 0, 0,
 512                                data, 65536, __va(nvram_base), 65536);
 513         return status;
 514 }
 515 #endif
 516
 517
 518 /*
 519  * Initialization
 520  */
 521
 522 void pnpbios_calls_init(union pnp_bios_install_struct *header)
 523 {
 524         int i;
 525         spin_lock_init(&pnp_bios_lock);
 526         pnp_bios_callpoint.offset = header->fields.pm16offset;
 527         pnp_bios_callpoint.segment = PNP_CS16;
 528
 529         set_base(bad_bios_desc, __va((unsigned long)0x40 << 4));
 530         _set_limit((char *)&bad_bios_desc, 4095 - (0x40 << 4));
 531         for (i = 0; i < NR_CPUS; i++) {
 532                 struct desc_struct *gdt = get_cpu_gdt_table(i);
 533                 if (!gdt)
 534                         continue;
 535                 Q2_SET_SEL(i, PNP_CS32, &pnp_bios_callfunc, 64 * 1024);
 536                 Q_SET_SEL(i, PNP_CS16, header->fields.pm16cseg, 64 * 1024);
 537                 Q_SET_SEL(i, PNP_DS, header->fields.pm16dseg, 64 * 1024);
 538         }
 539 }