drivers/pnp/pnpbios/bioscalls.c

   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/system.h>
  21 #include <asm/byteorder.h>
  22
  23 #include "pnpbios.h"
  24
  25 static struct {
  26         u16 offset;
  27         u16 segment;
  28 } pnp_bios_callpoint;
  29
  30 /*
  31  * These are some opcodes for a "static asmlinkage"
  32  * As this code is *not* executed inside the linux kernel segment, but in a
  33  * alias at offset 0, we need a far return that can not be compiled by
  34  * default (please, prove me wrong! this is *really* ugly!)
  35  * This is the only way to get the bios to return into the kernel code,
  36  * because the bios code runs in 16 bit protected mode and therefore can only
  37  * return to the caller if the call is within the first 64kB, and the linux
  38  * kernel begins at offset 3GB...
  39  */
  40
  41 asmlinkage void pnp_bios_callfunc(void);
  42
  43 __asm__(".text                  \n"
  44         __ALIGN_STR "\n"
  45         "pnp_bios_callfunc:\n"
  46         "       pushl %edx      \n"
  47         "       pushl %ecx      \n"
  48         "       pushl %ebx      \n"
  49         "       pushl %eax      \n"
  50         "       lcallw *pnp_bios_callpoint\n"
  51         "       addl $16, %esp  \n"
  52         "       lret            \n"
  53         ".previous              \n");
  54
  55 #define Q2_SET_SEL(cpu, selname, address, size) \
  56 do { \
  57         struct desc_struct *gdt = get_cpu_gdt_table((cpu)); \
  58         set_desc_base(&gdt[(selname) >> 3], (u32)(address)); \
  59         set_desc_limit(&gdt[(selname) >> 3], (size) - 1); \
  60 } while(0)
  61
  62 static struct desc_struct bad_bios_desc = GDT_ENTRY_INIT(0x4092,
  63                         (unsigned long)__va(0x400UL), PAGE_SIZE - 0x400 - 1);
  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
  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
 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 occurred\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  */
 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
 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  */
 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
 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  */
 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
 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  */
 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  */
 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
 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  */
 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
 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  */
 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
 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  */
 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
 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
 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         for_each_possible_cpu(i) {
 480                 struct desc_struct *gdt = get_cpu_gdt_table(i);
 481                 if (!gdt)
 482                         continue;
 483                 set_desc_base(&gdt[GDT_ENTRY_PNPBIOS_CS32],
 484                          (unsigned long)&pnp_bios_callfunc);
 485                 set_desc_base(&gdt[GDT_ENTRY_PNPBIOS_CS16],
 486                          (unsigned long)__va(header->fields.pm16cseg));
 487                 set_desc_base(&gdt[GDT_ENTRY_PNPBIOS_DS],
 488                          (unsigned long)__va(header->fields.pm16dseg));
 489         }
 490 }