LXR linux/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/byteorder.h>
  21
  22#include "pnpbios.h"
  23
  24__visible 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
  40asmlinkage __visible void pnp_bios_callfunc(void);
  41
  42__asm__(".text                  \n"
  43        __ALIGN_STR "\n"
  44        ".globl pnp_bios_callfunc\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) \
  56do { \
  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
  62static 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__visible u32 pnp_bios_fault_esp;
  71__visible u32 pnp_bios_fault_eip;
  72__visible u32 pnp_bios_is_utter_crap = 0;
  73
  74static spinlock_t pnp_bios_lock;
  75
  76/*
  77 * Support Functions
  78 */
  79
  80static 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
 153void 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 */
 253static 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
 266int 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 */
 289static 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
 307int 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 */
 323static 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
 338int 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 */
 358int 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 */
 375static 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
 386int 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 */
 399static 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
 411int 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 */
 424static 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
 436int 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 */
 450static 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
 461int 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
 471void 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}
 491