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 Q2_SET_SEL(cpu, selname, address, size) \
  62 do { \
  63 struct desc_struct *gdt = get_cpu_gdt_table((cpu)); \
  64 set_base(gdt[(selname) >> 3], (u32)(address)); \
  65 set_limit(gdt[(selname) >> 3], size); \
  66 } while(0)
  67
  68 static struct desc_struct bad_bios_desc = { 0, 0x00409200 };
  69
  70 /*
  71  * At some point we want to use this stack frame pointer to unwind
  72  * after PnP BIOS oopses.
  73  */
  74
  75 u32 pnp_bios_fault_esp;
  76 u32 pnp_bios_fault_eip;
  77 u32 pnp_bios_is_utter_crap = 0;
  78
  79 static spinlock_t pnp_bios_lock;
  80
  81
  82 /*
  83  * Support Functions
  84  */
  85
  86 static inline u16 call_pnp_bios(u16 func, u16 arg1, u16 arg2, u16 arg3,
  87                                 u16 arg4, u16 arg5, u16 arg6, u16 arg7,
  88                                 void *ts1_base, u32 ts1_size,
  89                                 void *ts2_base, u32 ts2_size)
  90 {
  91         unsigned long flags;
  92         u16 status;
  93         struct desc_struct save_desc_40;
  94         int cpu;
  95
  96         /*
  97          * PnP BIOSes are generally not terribly re-entrant.
  98          * Also, don't rely on them to save everything correctly.
  99          */
 100         if(pnp_bios_is_utter_crap)
 101                 return PNP_FUNCTION_NOT_SUPPORTED;
 102
 103         cpu = get_cpu();
 104         save_desc_40 = get_cpu_gdt_table(cpu)[0x40 / 8];
 105         get_cpu_gdt_table(cpu)[0x40 / 8] = bad_bios_desc;
 106
 107         /* On some boxes IRQ's during PnP BIOS calls are deadly.  */
 108         spin_lock_irqsave(&pnp_bios_lock, flags);
 109
 110         /* The lock prevents us bouncing CPU here */
 111         if (ts1_size)
 112                 Q2_SET_SEL(smp_processor_id(), PNP_TS1, ts1_base, ts1_size);
 113         if (ts2_size)
 114                 Q2_SET_SEL(smp_processor_id(), PNP_TS2, ts2_base, ts2_size);
 115
 116         __asm__ __volatile__(
 117                 "pushl %%ebp\n\t"
 118                 "pushl %%edi\n\t"
 119                 "pushl %%esi\n\t"
 120                 "pushl %%ds\n\t"
 121                 "pushl %%es\n\t"
 122                 "pushl %%fs\n\t"
 123                 "pushl %%gs\n\t"
 124                 "pushfl\n\t"
 125                 "movl %%esp, pnp_bios_fault_esp\n\t"
 126                 "movl $1f, pnp_bios_fault_eip\n\t"
 127                 "lcall %5,%6\n\t"
 128                 "1:popfl\n\t"
 129                 "popl %%gs\n\t"
 130                 "popl %%fs\n\t"
 131                 "popl %%es\n\t"
 132                 "popl %%ds\n\t"
 133                 "popl %%esi\n\t"
 134                 "popl %%edi\n\t"
 135                 "popl %%ebp\n\t"
 136                 : "=a" (status)
 137                 : "0" ((func) | (((u32)arg1) << 16)),
 138                   "b" ((arg2) | (((u32)arg3) << 16)),
 139                   "c" ((arg4) | (((u32)arg5) << 16)),
 140                   "d" ((arg6) | (((u32)arg7) << 16)),
 141                   "i" (PNP_CS32),
 142                   "i" (0)
 143                 : "memory"
 144         );
 145         spin_unlock_irqrestore(&pnp_bios_lock, flags);
 146
 147         get_cpu_gdt_table(cpu)[0x40 / 8] = save_desc_40;
 148         put_cpu();
 149
 150         /* If we get here and this is set then the PnP BIOS faulted on us. */
 151         if(pnp_bios_is_utter_crap)
 152         {
 153                 printk(KERN_ERR "PnPBIOS: Warning! Your PnP BIOS caused a fatal error. Attempting to continue\n");
 154                 printk(KERN_ERR "PnPBIOS: You may need to reboot with the \"pnpbios=off\" option to operate stably\n");
 155                 printk(KERN_ERR "PnPBIOS: Check with your vendor for an updated BIOS\n");
 156         }
 157
 158         return status;
 159 }
 160
 161 void pnpbios_print_status(const char * module, u16 status)
 162 {
 163         switch(status) {
 164         case PNP_SUCCESS:
 165                 printk(KERN_ERR "PnPBIOS: %s: function successful\n", module);
 166                 break;
 167         case PNP_NOT_SET_STATICALLY:
 168                 printk(KERN_ERR "PnPBIOS: %s: unable to set static resources\n", module);
 169                 break;
 170         case PNP_UNKNOWN_FUNCTION:
 171                 printk(KERN_ERR "PnPBIOS: %s: invalid function number passed\n", module);
 172                 break;
 173         case PNP_FUNCTION_NOT_SUPPORTED:
 174                 printk(KERN_ERR "PnPBIOS: %s: function not supported on this system\n", module);
 175                 break;
 176         case PNP_INVALID_HANDLE:
 177                 printk(KERN_ERR "PnPBIOS: %s: invalid handle\n", module);
 178                 break;
 179         case PNP_BAD_PARAMETER:
 180                 printk(KERN_ERR "PnPBIOS: %s: invalid parameters were passed\n", module);
 181                 break;
 182         case PNP_SET_FAILED:
 183                 printk(KERN_ERR "PnPBIOS: %s: unable to set resources\n", module);
 184                 break;
 185         case PNP_EVENTS_NOT_PENDING:
 186                 printk(KERN_ERR "PnPBIOS: %s: no events are pending\n", module);
 187                 break;
 188         case PNP_SYSTEM_NOT_DOCKED:
 189                 printk(KERN_ERR "PnPBIOS: %s: the system is not docked\n", module);
 190                 break;
 191         case PNP_NO_ISA_PNP_CARDS:
 192                 printk(KERN_ERR "PnPBIOS: %s: no isapnp cards are installed on this system\n", module);
 193                 break;
 194         case PNP_UNABLE_TO_DETERMINE_DOCK_CAPABILITIES:
 195                 printk(KERN_ERR "PnPBIOS: %s: cannot determine the capabilities of the docking station\n", module);
 196                 break;
 197         case PNP_CONFIG_CHANGE_FAILED_NO_BATTERY:
 198                 printk(KERN_ERR "PnPBIOS: %s: unable to undock, the system does not have a battery\n", module);
 199                 break;
 200         case PNP_CONFIG_CHANGE_FAILED_RESOURCE_CONFLICT:
 201                 printk(KERN_ERR "PnPBIOS: %s: could not dock due to resource conflicts\n", module);
 202                 break;
 203         case PNP_BUFFER_TOO_SMALL:
 204                 printk(KERN_ERR "PnPBIOS: %s: the buffer passed is too small\n", module);
 205                 break;
 206         case PNP_USE_ESCD_SUPPORT:
 207                 printk(KERN_ERR "PnPBIOS: %s: use ESCD instead\n", module);
 208                 break;
 209         case PNP_MESSAGE_NOT_SUPPORTED:
 210                 printk(KERN_ERR "PnPBIOS: %s: the message is unsupported\n", module);
 211                 break;
 212         case PNP_HARDWARE_ERROR:
 213                 printk(KERN_ERR "PnPBIOS: %s: a hardware failure has occured\n", module);
 214                 break;
 215         default:
 216                 printk(KERN_ERR "PnPBIOS: %s: unexpected status 0x%x\n", module, status);
 217                 break;
 218         }
 219 }
 220
 221
 222 /*
 223  * PnP BIOS Low Level Calls
 224  */
 225
 226 #define PNP_GET_NUM_SYS_DEV_NODES               0x00
 227 #define PNP_GET_SYS_DEV_NODE                    0x01
 228 #define PNP_SET_SYS_DEV_NODE                    0x02
 229 #define PNP_GET_EVENT                           0x03
 230 #define PNP_SEND_MESSAGE                        0x04
 231 #define PNP_GET_DOCKING_STATION_INFORMATION     0x05
 232 #define PNP_SET_STATIC_ALLOCED_RES_INFO         0x09
 233 #define PNP_GET_STATIC_ALLOCED_RES_INFO         0x0a
 234 #define PNP_GET_APM_ID_TABLE                    0x0b
 235 #define PNP_GET_PNP_ISA_CONFIG_STRUC            0x40
 236 #define PNP_GET_ESCD_INFO                       0x41
 237 #define PNP_READ_ESCD                           0x42
 238 #define PNP_WRITE_ESCD                          0x43
 239
 240 /*
 241  * Call PnP BIOS with function 0x00, "get number of system device nodes"
 242  */
 243 static int __pnp_bios_dev_node_info(struct pnp_dev_node_info *data)
 244 {
 245         u16 status;
 246         if (!pnp_bios_present())
 247                 return PNP_FUNCTION_NOT_SUPPORTED;
 248         status = call_pnp_bios(PNP_GET_NUM_SYS_DEV_NODES, 0, PNP_TS1, 2, PNP_TS1, PNP_DS, 0, 0,
 249                                data, sizeof(struct pnp_dev_node_info), NULL, 0);
 250         data->no_nodes &= 0xff;
 251         return status;
 252 }
 253
 254 int pnp_bios_dev_node_info(struct pnp_dev_node_info *data)
 255 {
 256         int status = __pnp_bios_dev_node_info( data );
 257         if ( status )
 258                 pnpbios_print_status( "dev_node_info", status );
 259         return status;
 260 }
 261
 262 /*
 263  * Note that some PnP BIOSes (e.g., on Sony Vaio laptops) die a horrible
 264  * death if they are asked to access the "current" configuration.
 265  * Therefore, if it's a matter of indifference, it's better to call
 266  * get_dev_node() and set_dev_node() with boot=1 rather than with boot=0.
 267  */
 268
 269 /*
 270  * Call PnP BIOS with function 0x01, "get system device node"
 271  * Input: *nodenum = desired node,
 272  *        boot = whether to get nonvolatile boot (!=0)
 273  *               or volatile current (0) config
 274  * Output: *nodenum=next node or 0xff if no more nodes
 275  */
 276 static int __pnp_bios_get_dev_node(u8 *nodenum, char boot, struct pnp_bios_node *data)
 277 {
 278         u16 status;
 279         u16 tmp_nodenum;
 280         if (!pnp_bios_present())
 281                 return PNP_FUNCTION_NOT_SUPPORTED;
 282         if ( !boot && pnpbios_dont_use_current_config )
 283                 return PNP_FUNCTION_NOT_SUPPORTED;
 284         tmp_nodenum = *nodenum;
 285         status = call_pnp_bios(PNP_GET_SYS_DEV_NODE, 0, PNP_TS1, 0, PNP_TS2, boot ? 2 : 1, PNP_DS, 0,
 286                                &tmp_nodenum, sizeof(tmp_nodenum), data, 65536);
 287         *nodenum = tmp_nodenum;
 288         return status;
 289 }
 290
 291 int pnp_bios_get_dev_node(u8 *nodenum, char boot, struct pnp_bios_node *data)
 292 {
 293         int status;
 294         status =  __pnp_bios_get_dev_node( nodenum, boot, data );
 295         if ( status )
 296                 pnpbios_print_status( "get_dev_node", status );
 297         return status;
 298 }
 299
 300
 301 /*
 302  * Call PnP BIOS with function 0x02, "set system device node"
 303  * Input: *nodenum = desired node,
 304  *        boot = whether to set nonvolatile boot (!=0)
 305  *               or volatile current (0) config
 306  */
 307 static int __pnp_bios_set_dev_node(u8 nodenum, char boot, struct pnp_bios_node *data)
 308 {
 309         u16 status;
 310         if (!pnp_bios_present())
 311                 return PNP_FUNCTION_NOT_SUPPORTED;
 312         if ( !boot && pnpbios_dont_use_current_config )
 313                 return PNP_FUNCTION_NOT_SUPPORTED;
 314         status = call_pnp_bios(PNP_SET_SYS_DEV_NODE, nodenum, 0, PNP_TS1, boot ? 2 : 1, PNP_DS, 0, 0,
 315                                data, 65536, NULL, 0);
 316         return status;
 317 }
 318
 319 int pnp_bios_set_dev_node(u8 nodenum, char boot, struct pnp_bios_node *data)
 320 {
 321         int status;
 322         status =  __pnp_bios_set_dev_node( nodenum, boot, data );
 323         if ( status ) {
 324                 pnpbios_print_status( "set_dev_node", status );
 325                 return status;
 326         }
 327         if ( !boot ) { /* Update devlist */
 328                 status =  pnp_bios_get_dev_node( &nodenum, boot, data );
 329                 if ( status )
 330                         return status;
 331         }
 332         return status;
 333 }
 334
 335 #if needed
 336 /*
 337  * Call PnP BIOS with function 0x03, "get event"
 338  */
 339 static int pnp_bios_get_event(u16 *event)
 340 {
 341         u16 status;
 342         if (!pnp_bios_present())
 343                 return PNP_FUNCTION_NOT_SUPPORTED;
 344         status = call_pnp_bios(PNP_GET_EVENT, 0, PNP_TS1, PNP_DS, 0, 0 ,0 ,0,
 345                                event, sizeof(u16), NULL, 0);
 346         return status;
 347 }
 348 #endif
 349
 350 #if needed
 351 /*
 352  * Call PnP BIOS with function 0x04, "send message"
 353  */
 354 static int pnp_bios_send_message(u16 message)
 355 {
 356         u16 status;
 357         if (!pnp_bios_present())
 358                 return PNP_FUNCTION_NOT_SUPPORTED;
 359         status = call_pnp_bios(PNP_SEND_MESSAGE, message, PNP_DS, 0, 0, 0, 0, 0, 0, 0, 0, 0);
 360         return status;
 361 }
 362 #endif
 363
 364 /*
 365  * Call PnP BIOS with function 0x05, "get docking station information"
 366  */
 367 int pnp_bios_dock_station_info(struct pnp_docking_station_info *data)
 368 {
 369         u16 status;
 370         if (!pnp_bios_present())
 371                 return PNP_FUNCTION_NOT_SUPPORTED;
 372         status = call_pnp_bios(PNP_GET_DOCKING_STATION_INFORMATION, 0, PNP_TS1, PNP_DS, 0, 0, 0, 0,
 373                                data, sizeof(struct pnp_docking_station_info), NULL, 0);
 374         return status;
 375 }
 376
 377 #if needed
 378 /*
 379  * Call PnP BIOS with function 0x09, "set statically allocated resource
 380  * information"
 381  */
 382 static int pnp_bios_set_stat_res(char *info)
 383 {
 384         u16 status;
 385         if (!pnp_bios_present())
 386                 return PNP_FUNCTION_NOT_SUPPORTED;
 387         status = call_pnp_bios(PNP_SET_STATIC_ALLOCED_RES_INFO, 0, PNP_TS1, PNP_DS, 0, 0, 0, 0,
 388                                info, *((u16 *) info), 0, 0);
 389         return status;
 390 }
 391 #endif
 392
 393 /*
 394  * Call PnP BIOS with function 0x0a, "get statically allocated resource
 395  * information"
 396  */
 397 static int __pnp_bios_get_stat_res(char *info)
 398 {
 399         u16 status;
 400         if (!pnp_bios_present())
 401                 return PNP_FUNCTION_NOT_SUPPORTED;
 402         status = call_pnp_bios(PNP_GET_STATIC_ALLOCED_RES_INFO, 0, PNP_TS1, PNP_DS, 0, 0, 0, 0,
 403                                info, 65536, NULL, 0);
 404         return status;
 405 }
 406
 407 int pnp_bios_get_stat_res(char *info)
 408 {
 409         int status;
 410         status = __pnp_bios_get_stat_res( info );
 411         if ( status )
 412                 pnpbios_print_status( "get_stat_res", status );
 413         return status;
 414 }
 415
 416 #if needed
 417 /*
 418  * Call PnP BIOS with function 0x0b, "get APM id table"
 419  */
 420 static int pnp_bios_apm_id_table(char *table, u16 *size)
 421 {
 422         u16 status;
 423         if (!pnp_bios_present())
 424                 return PNP_FUNCTION_NOT_SUPPORTED;
 425         status = call_pnp_bios(PNP_GET_APM_ID_TABLE, 0, PNP_TS2, 0, PNP_TS1, PNP_DS, 0, 0,
 426                                table, *size, size, sizeof(u16));
 427         return status;
 428 }
 429 #endif
 430
 431 /*
 432  * Call PnP BIOS with function 0x40, "get isa pnp configuration structure"
 433  */
 434 static int __pnp_bios_isapnp_config(struct pnp_isa_config_struc *data)
 435 {
 436         u16 status;
 437         if (!pnp_bios_present())
 438                 return PNP_FUNCTION_NOT_SUPPORTED;
 439         status = call_pnp_bios(PNP_GET_PNP_ISA_CONFIG_STRUC, 0, PNP_TS1, PNP_DS, 0, 0, 0, 0,
 440                                data, sizeof(struct pnp_isa_config_struc), NULL, 0);
 441         return status;
 442 }
 443
 444 int pnp_bios_isapnp_config(struct pnp_isa_config_struc *data)
 445 {
 446         int status;
 447         status = __pnp_bios_isapnp_config( data );
 448         if ( status )
 449                 pnpbios_print_status( "isapnp_config", status );
 450         return status;
 451 }
 452
 453 /*
 454  * Call PnP BIOS with function 0x41, "get ESCD info"
 455  */
 456 static int __pnp_bios_escd_info(struct escd_info_struc *data)
 457 {
 458         u16 status;
 459         if (!pnp_bios_present())
 460                 return ESCD_FUNCTION_NOT_SUPPORTED;
 461         status = call_pnp_bios(PNP_GET_ESCD_INFO, 0, PNP_TS1, 2, PNP_TS1, 4, PNP_TS1, PNP_DS,
 462                                data, sizeof(struct escd_info_struc), NULL, 0);
 463         return status;
 464 }
 465
 466 int pnp_bios_escd_info(struct escd_info_struc *data)
 467 {
 468         int status;
 469         status = __pnp_bios_escd_info( data );
 470         if ( status )
 471                 pnpbios_print_status( "escd_info", status );
 472         return status;
 473 }
 474
 475 /*
 476  * Call PnP BIOS function 0x42, "read ESCD"
 477  * nvram_base is determined by calling escd_info
 478  */
 479 static int __pnp_bios_read_escd(char *data, u32 nvram_base)
 480 {
 481         u16 status;
 482         if (!pnp_bios_present())
 483                 return ESCD_FUNCTION_NOT_SUPPORTED;
 484         status = call_pnp_bios(PNP_READ_ESCD, 0, PNP_TS1, PNP_TS2, PNP_DS, 0, 0, 0,
 485                                data, 65536, __va(nvram_base), 65536);
 486         return status;
 487 }
 488
 489 int pnp_bios_read_escd(char *data, u32 nvram_base)
 490 {
 491         int status;
 492         status = __pnp_bios_read_escd( data, nvram_base );
 493         if ( status )
 494                 pnpbios_print_status( "read_escd", status );
 495         return status;
 496 }
 497
 498 #if needed
 499 /*
 500  * Call PnP BIOS function 0x43, "write ESCD"
 501  */
 502 static int pnp_bios_write_escd(char *data, u32 nvram_base)
 503 {
 504         u16 status;
 505         if (!pnp_bios_present())
 506                 return ESCD_FUNCTION_NOT_SUPPORTED;
 507         status = call_pnp_bios(PNP_WRITE_ESCD, 0, PNP_TS1, PNP_TS2, PNP_DS, 0, 0, 0,
 508                                data, 65536, __va(nvram_base), 65536);
 509         return status;
 510 }
 511 #endif
 512
 513
 514 /*
 515  * Initialization
 516  */
 517
 518 void pnpbios_calls_init(union pnp_bios_install_struct *header)
 519 {
 520         int i;
 521         spin_lock_init(&pnp_bios_lock);
 522         pnp_bios_callpoint.offset = header->fields.pm16offset;
 523         pnp_bios_callpoint.segment = PNP_CS16;
 524
 525         set_base(bad_bios_desc, __va((unsigned long)0x40 << 4));
 526         _set_limit((char *)&bad_bios_desc, 4095 - (0x40 << 4));
 527         for (i = 0; i < NR_CPUS; i++) {
 528                 struct desc_struct *gdt = get_cpu_gdt_table(i);
 529                 if (!gdt)
 530                         continue;
 531                 set_base(gdt[GDT_ENTRY_PNPBIOS_CS32], &pnp_bios_callfunc);
 532                 set_base(gdt[GDT_ENTRY_PNPBIOS_CS16], __va(header->fields.pm16cseg));
 533                 set_base(gdt[GDT_ENTRY_PNPBIOS_DS], __va(header->fields.pm16dseg));
 534         }
 535 }