api/api.c

   1 /*
   2  * (C) Copyright 2007 Semihalf
   3  *
   4  * Written by: Rafal Jaworowski <raj@semihalf.com>
   5  *
   6  * SPDX-License-Identifier:     GPL-2.0+
   7  */
   8
   9 #include <config.h>
  10 #include <command.h>
  11 #include <common.h>
  12 #include <malloc.h>
  13 #include <environment.h>
  14 #include <linux/types.h>
  15 #include <api_public.h>
  16
  17 #include "api_private.h"
  18
  19 #define DEBUG
  20 #undef DEBUG
  21
  22 /*****************************************************************************
  23  *
  24  * This is the API core.
  25  *
  26  * API_ functions are part of U-Boot code and constitute the lowest level
  27  * calls:
  28  *
  29  *  - they know what values they need as arguments
  30  *  - their direct return value pertains to the API_ "shell" itself (0 on
  31  *    success, some error code otherwise)
  32  *  - if the call returns a value it is buried within arguments
  33  *
  34  ****************************************************************************/
  35
  36 #ifdef DEBUG
  37 #define debugf(fmt, args...) do { printf("%s(): ", __func__); printf(fmt, ##args); } while (0)
  38 #else
  39 #define debugf(fmt, args...)
  40 #endif
  41
  42 typedef int (*cfp_t)(va_list argp);
  43
  44 static int calls_no;
  45
  46 /*
  47  * pseudo signature:
  48  *
  49  * int API_getc(int *c)
  50  */
  51 static int API_getc(va_list ap)
  52 {
  53         int *c;
  54
  55         if ((c = (int *)va_arg(ap, uintptr_t)) == NULL)
  56                 return API_EINVAL;
  57
  58         *c = getc();
  59         return 0;
  60 }
  61
  62 /*
  63  * pseudo signature:
  64  *
  65  * int API_tstc(int *c)
  66  */
  67 static int API_tstc(va_list ap)
  68 {
  69         int *t;
  70
  71         if ((t = (int *)va_arg(ap, uintptr_t)) == NULL)
  72                 return API_EINVAL;
  73
  74         *t = tstc();
  75         return 0;
  76 }
  77
  78 /*
  79  * pseudo signature:
  80  *
  81  * int API_putc(char *ch)
  82  */
  83 static int API_putc(va_list ap)
  84 {
  85         char *c;
  86
  87         if ((c = (char *)va_arg(ap, uintptr_t)) == NULL)
  88                 return API_EINVAL;
  89
  90         putc(*c);
  91         return 0;
  92 }
  93
  94 /*
  95  * pseudo signature:
  96  *
  97  * int API_puts(char **s)
  98  */
  99 static int API_puts(va_list ap)
 100 {
 101         char *s;
 102
 103         if ((s = (char *)va_arg(ap, uintptr_t)) == NULL)
 104                 return API_EINVAL;
 105
 106         puts(s);
 107         return 0;
 108 }
 109
 110 /*
 111  * pseudo signature:
 112  *
 113  * int API_reset(void)
 114  */
 115 static int API_reset(va_list ap)
 116 {
 117         do_reset(NULL, 0, 0, NULL);
 118
 119         /* NOT REACHED */
 120         return 0;
 121 }
 122
 123 /*
 124  * pseudo signature:
 125  *
 126  * int API_get_sys_info(struct sys_info *si)
 127  *
 128  * fill out the sys_info struct containing selected parameters about the
 129  * machine
 130  */
 131 static int API_get_sys_info(va_list ap)
 132 {
 133         struct sys_info *si;
 134
 135         si = (struct sys_info *)va_arg(ap, uintptr_t);
 136         if (si == NULL)
 137                 return API_ENOMEM;
 138
 139         return (platform_sys_info(si)) ? 0 : API_ENODEV;
 140 }
 141
 142 /*
 143  * pseudo signature:
 144  *
 145  * int API_udelay(unsigned long *udelay)
 146  */
 147 static int API_udelay(va_list ap)
 148 {
 149         unsigned long *d;
 150
 151         if ((d = (unsigned long *)va_arg(ap, unsigned long)) == NULL)
 152                 return API_EINVAL;
 153
 154         udelay(*d);
 155         return 0;
 156 }
 157
 158 /*
 159  * pseudo signature:
 160  *
 161  * int API_get_timer(unsigned long *current, unsigned long *base)
 162  */
 163 static int API_get_timer(va_list ap)
 164 {
 165         unsigned long *base, *cur;
 166
 167         cur = (unsigned long *)va_arg(ap, unsigned long);
 168         if (cur == NULL)
 169                 return API_EINVAL;
 170
 171         base = (unsigned long *)va_arg(ap, unsigned long);
 172         if (base == NULL)
 173                 return API_EINVAL;
 174
 175         *cur = get_timer(*base);
 176         return 0;
 177 }
 178
 179
 180 /*****************************************************************************
 181  *
 182  * pseudo signature:
 183  *
 184  * int API_dev_enum(struct device_info *)
 185  *
 186  *
 187  * cookies uniqely identify the previously enumerated device instance and
 188  * provide a hint for what to inspect in current enum iteration:
 189  *
 190  *   - net: &eth_device struct address from list pointed to by eth_devices
 191  *
 192  *   - storage: struct blk_desc struct address from &ide_dev_desc[n],
 193  *     &scsi_dev_desc[n] and similar tables
 194  *
 195  ****************************************************************************/
 196
 197 static int API_dev_enum(va_list ap)
 198 {
 199         struct device_info *di;
 200
 201         /* arg is ptr to the device_info struct we are going to fill out */
 202         di = (struct device_info *)va_arg(ap, uintptr_t);
 203         if (di == NULL)
 204                 return API_EINVAL;
 205
 206         if (di->cookie == NULL) {
 207                 /* start over - clean up enumeration */
 208                 dev_enum_reset();       /* XXX shouldn't the name contain 'stor'? */
 209                 debugf("RESTART ENUM\n");
 210
 211                 /* net device enumeration first */
 212                 if (dev_enum_net(di))
 213                         return 0;
 214         }
 215
 216         /*
 217          * The hidden assumption is there can only be one active network
 218          * device and it is identified upon enumeration (re)start, so there's
 219          * no point in trying to find network devices in other cases than the
 220          * (re)start and hence the 'next' device can only be storage
 221          */
 222         if (!dev_enum_storage(di))
 223                 /* make sure we mark there are no more devices */
 224                 di->cookie = NULL;
 225
 226         return 0;
 227 }
 228
 229
 230 static int API_dev_open(va_list ap)
 231 {
 232         struct device_info *di;
 233         int err = 0;
 234
 235         /* arg is ptr to the device_info struct */
 236         di = (struct device_info *)va_arg(ap, uintptr_t);
 237         if (di == NULL)
 238                 return API_EINVAL;
 239
 240         /* Allow only one consumer of the device at a time */
 241         if (di->state == DEV_STA_OPEN)
 242                 return API_EBUSY;
 243
 244         if (di->cookie == NULL)
 245                 return API_ENODEV;
 246
 247         if (di->type & DEV_TYP_STOR)
 248                 err = dev_open_stor(di->cookie);
 249
 250         else if (di->type & DEV_TYP_NET)
 251                 err = dev_open_net(di->cookie);
 252         else
 253                 err = API_ENODEV;
 254
 255         if (!err)
 256                 di->state = DEV_STA_OPEN;
 257
 258         return err;
 259 }
 260
 261
 262 static int API_dev_close(va_list ap)
 263 {
 264         struct device_info *di;
 265         int err = 0;
 266
 267         /* arg is ptr to the device_info struct */
 268         di = (struct device_info *)va_arg(ap, uintptr_t);
 269         if (di == NULL)
 270                 return API_EINVAL;
 271
 272         if (di->state == DEV_STA_CLOSED)
 273                 return 0;
 274
 275         if (di->cookie == NULL)
 276                 return API_ENODEV;
 277
 278         if (di->type & DEV_TYP_STOR)
 279                 err = dev_close_stor(di->cookie);
 280
 281         else if (di->type & DEV_TYP_NET)
 282                 err = dev_close_net(di->cookie);
 283         else
 284                 /*
 285                  * In case of unknown device we cannot change its state, so
 286                  * only return error code
 287                  */
 288                 err = API_ENODEV;
 289
 290         if (!err)
 291                 di->state = DEV_STA_CLOSED;
 292
 293         return err;
 294 }
 295
 296
 297 /*
 298  * Notice: this is for sending network packets only, as U-Boot does not
 299  * support writing to storage at the moment (12.2007)
 300  *
 301  * pseudo signature:
 302  *
 303  * int API_dev_write(
 304  *      struct device_info *di,
 305  *      void *buf,
 306  *      int *len
 307  * )
 308  *
 309  * buf: ptr to buffer from where to get the data to send
 310  *
 311  * len: length of packet to be sent (in bytes)
 312  *
 313  */
 314 static int API_dev_write(va_list ap)
 315 {
 316         struct device_info *di;
 317         void *buf;
 318         int *len;
 319         int err = 0;
 320
 321         /* 1. arg is ptr to the device_info struct */
 322         di = (struct device_info *)va_arg(ap, uintptr_t);
 323         if (di == NULL)
 324                 return API_EINVAL;
 325
 326         /* XXX should we check if device is open? i.e. the ->state ? */
 327
 328         if (di->cookie == NULL)
 329                 return API_ENODEV;
 330
 331         /* 2. arg is ptr to buffer from where to get data to write */
 332         buf = (void *)va_arg(ap, uintptr_t);
 333         if (buf == NULL)
 334                 return API_EINVAL;
 335
 336         /* 3. arg is length of buffer */
 337         len = (int *)va_arg(ap, uintptr_t);
 338         if (len == NULL)
 339                 return API_EINVAL;
 340         if (*len <= 0)
 341                 return API_EINVAL;
 342
 343         if (di->type & DEV_TYP_STOR)
 344                 /*
 345                  * write to storage is currently not supported by U-Boot:
 346                  * no storage device implements block_write() method
 347                  */
 348                 return API_ENODEV;
 349
 350         else if (di->type & DEV_TYP_NET)
 351                 err = dev_write_net(di->cookie, buf, *len);
 352         else
 353                 err = API_ENODEV;
 354
 355         return err;
 356 }
 357
 358
 359 /*
 360  * pseudo signature:
 361  *
 362  * int API_dev_read(
 363  *      struct device_info *di,
 364  *      void *buf,
 365  *      size_t *len,
 366  *      unsigned long *start
 367  *      size_t *act_len
 368  * )
 369  *
 370  * buf: ptr to buffer where to put the read data
 371  *
 372  * len: ptr to length to be read
 373  *      - network: len of packet to read (in bytes)
 374  *      - storage: # of blocks to read (can vary in size depending on define)
 375  *
 376  * start: ptr to start block (only used for storage devices, ignored for
 377  *        network)
 378  *
 379  * act_len: ptr to where to put the len actually read
 380  */
 381 static int API_dev_read(va_list ap)
 382 {
 383         struct device_info *di;
 384         void *buf;
 385         lbasize_t *len_stor, *act_len_stor;
 386         lbastart_t *start;
 387         int *len_net, *act_len_net;
 388
 389         /* 1. arg is ptr to the device_info struct */
 390         di = (struct device_info *)va_arg(ap, uintptr_t);
 391         if (di == NULL)
 392                 return API_EINVAL;
 393
 394         /* XXX should we check if device is open? i.e. the ->state ? */
 395
 396         if (di->cookie == NULL)
 397                 return API_ENODEV;
 398
 399         /* 2. arg is ptr to buffer from where to put the read data */
 400         buf = (void *)va_arg(ap, uintptr_t);
 401         if (buf == NULL)
 402                 return API_EINVAL;
 403
 404         if (di->type & DEV_TYP_STOR) {
 405                 /* 3. arg - ptr to var with # of blocks to read */
 406                 len_stor = (lbasize_t *)va_arg(ap, uintptr_t);
 407                 if (!len_stor)
 408                         return API_EINVAL;
 409                 if (*len_stor <= 0)
 410                         return API_EINVAL;
 411
 412                 /* 4. arg - ptr to var with start block */
 413                 start = (lbastart_t *)va_arg(ap, uintptr_t);
 414
 415                 /* 5. arg - ptr to var where to put the len actually read */
 416                 act_len_stor = (lbasize_t *)va_arg(ap, uintptr_t);
 417                 if (!act_len_stor)
 418                         return API_EINVAL;
 419
 420                 *act_len_stor = dev_read_stor(di->cookie, buf, *len_stor, *start);
 421
 422         } else if (di->type & DEV_TYP_NET) {
 423
 424                 /* 3. arg points to the var with length of packet to read */
 425                 len_net = (int *)va_arg(ap, uintptr_t);
 426                 if (!len_net)
 427                         return API_EINVAL;
 428                 if (*len_net <= 0)
 429                         return API_EINVAL;
 430
 431                 /* 4. - ptr to var where to put the len actually read */
 432                 act_len_net = (int *)va_arg(ap, uintptr_t);
 433                 if (!act_len_net)
 434                         return API_EINVAL;
 435
 436                 *act_len_net = dev_read_net(di->cookie, buf, *len_net);
 437
 438         } else
 439                 return API_ENODEV;
 440
 441         return 0;
 442 }
 443
 444
 445 /*
 446  * pseudo signature:
 447  *
 448  * int API_env_get(const char *name, char **value)
 449  *
 450  * name: ptr to name of env var
 451  */
 452 static int API_env_get(va_list ap)
 453 {
 454         char *name, **value;
 455
 456         if ((name = (char *)va_arg(ap, uintptr_t)) == NULL)
 457                 return API_EINVAL;
 458         if ((value = (char **)va_arg(ap, uintptr_t)) == NULL)
 459                 return API_EINVAL;
 460
 461         *value = env_get(name);
 462
 463         return 0;
 464 }
 465
 466 /*
 467  * pseudo signature:
 468  *
 469  * int API_env_set(const char *name, const char *value)
 470  *
 471  * name: ptr to name of env var
 472  *
 473  * value: ptr to value to be set
 474  */
 475 static int API_env_set(va_list ap)
 476 {
 477         char *name, *value;
 478
 479         if ((name = (char *)va_arg(ap, uintptr_t)) == NULL)
 480                 return API_EINVAL;
 481         if ((value = (char *)va_arg(ap, uintptr_t)) == NULL)
 482                 return API_EINVAL;
 483
 484         env_set(name, value);
 485
 486         return 0;
 487 }
 488
 489 /*
 490  * pseudo signature:
 491  *
 492  * int API_env_enum(const char *last, char **next)
 493  *
 494  * last: ptr to name of env var found in last iteration
 495  */
 496 static int API_env_enum(va_list ap)
 497 {
 498         int i, buflen;
 499         char *last, **next, *s;
 500         ENTRY *match, search;
 501         static char *var;
 502
 503         last = (char *)va_arg(ap, unsigned long);
 504
 505         if ((next = (char **)va_arg(ap, uintptr_t)) == NULL)
 506                 return API_EINVAL;
 507
 508         if (last == NULL) {
 509                 var = NULL;
 510                 i = 0;
 511         } else {
 512                 var = strdup(last);
 513                 s = strchr(var, '=');
 514                 if (s != NULL)
 515                         *s = 0;
 516                 search.key = var;
 517                 i = hsearch_r(search, FIND, &match, &env_htab, 0);
 518                 if (i == 0) {
 519                         i = API_EINVAL;
 520                         goto done;
 521                 }
 522         }
 523
 524         /* match the next entry after i */
 525         i = hmatch_r("", i, &match, &env_htab);
 526         if (i == 0)
 527                 goto done;
 528         buflen = strlen(match->key) + strlen(match->data) + 2;
 529         var = realloc(var, buflen);
 530         snprintf(var, buflen, "%s=%s", match->key, match->data);
 531         *next = var;
 532         return 0;
 533
 534 done:
 535         free(var);
 536         var = NULL;
 537         *next = NULL;
 538         return i;
 539 }
 540
 541 /*
 542  * pseudo signature:
 543  *
 544  * int API_display_get_info(int type, struct display_info *di)
 545  */
 546 static int API_display_get_info(va_list ap)
 547 {
 548         int type;
 549         struct display_info *di;
 550
 551         type = va_arg(ap, int);
 552         di = va_arg(ap, struct display_info *);
 553
 554         return display_get_info(type, di);
 555 }
 556
 557 /*
 558  * pseudo signature:
 559  *
 560  * int API_display_draw_bitmap(ulong bitmap, int x, int y)
 561  */
 562 static int API_display_draw_bitmap(va_list ap)
 563 {
 564         ulong bitmap;
 565         int x, y;
 566
 567         bitmap = va_arg(ap, ulong);
 568         x = va_arg(ap, int);
 569         y = va_arg(ap, int);
 570
 571         return display_draw_bitmap(bitmap, x, y);
 572 }
 573
 574 /*
 575  * pseudo signature:
 576  *
 577  * void API_display_clear(void)
 578  */
 579 static int API_display_clear(va_list ap)
 580 {
 581         display_clear();
 582         return 0;
 583 }
 584
 585 static cfp_t calls_table[API_MAXCALL] = { NULL, };
 586
 587 /*
 588  * The main syscall entry point - this is not reentrant, only one call is
 589  * serviced until finished.
 590  *
 591  * e.g. syscall(1, int *, u_int32_t, u_int32_t, u_int32_t, u_int32_t);
 592  *
 593  * call:        syscall number
 594  *
 595  * retval:      points to the return value placeholder, this is the place the
 596  *              syscall puts its return value, if NULL the caller does not
 597  *              expect a return value
 598  *
 599  * ...          syscall arguments (variable number)
 600  *
 601  * returns:     0 if the call not found, 1 if serviced
 602  */
 603 int syscall(int call, int *retval, ...)
 604 {
 605         va_list ap;
 606         int rv;
 607
 608         if (call < 0 || call >= calls_no) {
 609                 debugf("invalid call #%d\n", call);
 610                 return 0;
 611         }
 612
 613         if (calls_table[call] == NULL) {
 614                 debugf("syscall #%d does not have a handler\n", call);
 615                 return 0;
 616         }
 617
 618         va_start(ap, retval);
 619         rv = calls_table[call](ap);
 620         if (retval != NULL)
 621                 *retval = rv;
 622
 623         return 1;
 624 }
 625
 626 void api_init(void)
 627 {
 628         struct api_signature *sig;
 629
 630         /* TODO put this into linker set one day... */
 631         calls_table[API_RSVD] = NULL;
 632         calls_table[API_GETC] = &API_getc;
 633         calls_table[API_PUTC] = &API_putc;
 634         calls_table[API_TSTC] = &API_tstc;
 635         calls_table[API_PUTS] = &API_puts;
 636         calls_table[API_RESET] = &API_reset;
 637         calls_table[API_GET_SYS_INFO] = &API_get_sys_info;
 638         calls_table[API_UDELAY] = &API_udelay;
 639         calls_table[API_GET_TIMER] = &API_get_timer;
 640         calls_table[API_DEV_ENUM] = &API_dev_enum;
 641         calls_table[API_DEV_OPEN] = &API_dev_open;
 642         calls_table[API_DEV_CLOSE] = &API_dev_close;
 643         calls_table[API_DEV_READ] = &API_dev_read;
 644         calls_table[API_DEV_WRITE] = &API_dev_write;
 645         calls_table[API_ENV_GET] = &API_env_get;
 646         calls_table[API_ENV_SET] = &API_env_set;
 647         calls_table[API_ENV_ENUM] = &API_env_enum;
 648         calls_table[API_DISPLAY_GET_INFO] = &API_display_get_info;
 649         calls_table[API_DISPLAY_DRAW_BITMAP] = &API_display_draw_bitmap;
 650         calls_table[API_DISPLAY_CLEAR] = &API_display_clear;
 651         calls_no = API_MAXCALL;
 652
 653         debugf("API initialized with %d calls\n", calls_no);
 654
 655         dev_stor_init();
 656
 657         /*
 658          * Produce the signature so the API consumers can find it
 659          */
 660         sig = malloc(sizeof(struct api_signature));
 661         if (sig == NULL) {
 662                 printf("API: could not allocate memory for the signature!\n");
 663                 return;
 664         }
 665
 666         env_set_hex("api_address", (unsigned long)sig);
 667         debugf("API sig @ 0x%lX\n", (unsigned long)sig);
 668         memcpy(sig->magic, API_SIG_MAGIC, 8);
 669         sig->version = API_SIG_VERSION;
 670         sig->syscall = &syscall;
 671         sig->checksum = 0;
 672         sig->checksum = crc32(0, (unsigned char *)sig,
 673                               sizeof(struct api_signature));
 674         debugf("syscall entry: 0x%lX\n", (unsigned long)sig->syscall);
 675 }
 676
 677 void platform_set_mr(struct sys_info *si, unsigned long start, unsigned long size,
 678                         int flags)
 679 {
 680         int i;
 681
 682         if (!si->mr || !size || (flags == 0))
 683                 return;
 684
 685         /* find free slot */
 686         for (i = 0; i < si->mr_no; i++)
 687                 if (si->mr[i].flags == 0) {
 688                         /* insert new mem region */
 689                         si->mr[i].start = start;
 690                         si->mr[i].size = size;
 691                         si->mr[i].flags = flags;
 692                         return;
 693                 }
 694 }