api/api.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * (C) Copyright 2007 Semihalf
   4  *
   5  * Written by: Rafal Jaworowski <raj@semihalf.com>
   6  */
   7
   8 #include <config.h>
   9 #include <command.h>
  10 #include <common.h>
  11 #include <env.h>
  12 #include <malloc.h>
  13 #include <env_internal.h>
  14 #include <linux/delay.h>
  15 #include <linux/types.h>
  16 #include <api_public.h>
  17 #include <u-boot/crc.h>
  18
  19 #include "api_private.h"
  20
  21 #define DEBUG
  22 #undef DEBUG
  23
  24 /*****************************************************************************
  25  *
  26  * This is the API core.
  27  *
  28  * API_ functions are part of U-Boot code and constitute the lowest level
  29  * calls:
  30  *
  31  *  - they know what values they need as arguments
  32  *  - their direct return value pertains to the API_ "shell" itself (0 on
  33  *    success, some error code otherwise)
  34  *  - if the call returns a value it is buried within arguments
  35  *
  36  ****************************************************************************/
  37
  38 #ifdef DEBUG
  39 #define debugf(fmt, args...) do { printf("%s(): ", __func__); printf(fmt, ##args); } while (0)
  40 #else
  41 #define debugf(fmt, args...)
  42 #endif
  43
  44 typedef int (*cfp_t)(va_list argp);
  45
  46 static int calls_no;
  47
  48 /*
  49  * pseudo signature:
  50  *
  51  * int API_getc(int *c)
  52  */
  53 static int API_getc(va_list ap)
  54 {
  55         int *c;
  56
  57         if ((c = (int *)va_arg(ap, uintptr_t)) == NULL)
  58                 return API_EINVAL;
  59
  60         *c = getchar();
  61         return 0;
  62 }
  63
  64 /*
  65  * pseudo signature:
  66  *
  67  * int API_tstc(int *c)
  68  */
  69 static int API_tstc(va_list ap)
  70 {
  71         int *t;
  72
  73         if ((t = (int *)va_arg(ap, uintptr_t)) == NULL)
  74                 return API_EINVAL;
  75
  76         *t = tstc();
  77         return 0;
  78 }
  79
  80 /*
  81  * pseudo signature:
  82  *
  83  * int API_putc(char *ch)
  84  */
  85 static int API_putc(va_list ap)
  86 {
  87         char *c;
  88
  89         if ((c = (char *)va_arg(ap, uintptr_t)) == NULL)
  90                 return API_EINVAL;
  91
  92         putc(*c);
  93         return 0;
  94 }
  95
  96 /*
  97  * pseudo signature:
  98  *
  99  * int API_puts(char **s)
 100  */
 101 static int API_puts(va_list ap)
 102 {
 103         char *s;
 104
 105         if ((s = (char *)va_arg(ap, uintptr_t)) == NULL)
 106                 return API_EINVAL;
 107
 108         puts(s);
 109         return 0;
 110 }
 111
 112 /*
 113  * pseudo signature:
 114  *
 115  * int API_reset(void)
 116  */
 117 static int API_reset(va_list ap)
 118 {
 119         do_reset(NULL, 0, 0, NULL);
 120
 121         /* NOT REACHED */
 122         return 0;
 123 }
 124
 125 /*
 126  * pseudo signature:
 127  *
 128  * int API_get_sys_info(struct sys_info *si)
 129  *
 130  * fill out the sys_info struct containing selected parameters about the
 131  * machine
 132  */
 133 static int API_get_sys_info(va_list ap)
 134 {
 135         struct sys_info *si;
 136
 137         si = (struct sys_info *)va_arg(ap, uintptr_t);
 138         if (si == NULL)
 139                 return API_ENOMEM;
 140
 141         return (platform_sys_info(si)) ? 0 : API_ENODEV;
 142 }
 143
 144 /*
 145  * pseudo signature:
 146  *
 147  * int API_udelay(unsigned long *udelay)
 148  */
 149 static int API_udelay(va_list ap)
 150 {
 151         unsigned long *d;
 152
 153         if ((d = (unsigned long *)va_arg(ap, unsigned long)) == NULL)
 154                 return API_EINVAL;
 155
 156         udelay(*d);
 157         return 0;
 158 }
 159
 160 /*
 161  * pseudo signature:
 162  *
 163  * int API_get_timer(unsigned long *current, unsigned long *base)
 164  */
 165 static int API_get_timer(va_list ap)
 166 {
 167         unsigned long *base, *cur;
 168
 169         cur = (unsigned long *)va_arg(ap, unsigned long);
 170         if (cur == NULL)
 171                 return API_EINVAL;
 172
 173         base = (unsigned long *)va_arg(ap, unsigned long);
 174         if (base == NULL)
 175                 return API_EINVAL;
 176
 177         *cur = get_timer(*base);
 178         return 0;
 179 }
 180
 181
 182 /*****************************************************************************
 183  *
 184  * pseudo signature:
 185  *
 186  * int API_dev_enum(struct device_info *)
 187  *
 188  *
 189  * cookies uniqely identify the previously enumerated device instance and
 190  * provide a hint for what to inspect in current enum iteration:
 191  *
 192  *   - net: &eth_device struct address from list pointed to by eth_devices
 193  *
 194  *   - storage: struct blk_desc struct address from &ide_dev_desc[n],
 195  *     &scsi_dev_desc[n] and similar tables
 196  *
 197  ****************************************************************************/
 198
 199 static int API_dev_enum(va_list ap)
 200 {
 201         struct device_info *di;
 202
 203         /* arg is ptr to the device_info struct we are going to fill out */
 204         di = (struct device_info *)va_arg(ap, uintptr_t);
 205         if (di == NULL)
 206                 return API_EINVAL;
 207
 208         if (di->cookie == NULL) {
 209                 /* start over - clean up enumeration */
 210                 dev_enum_reset();       /* XXX shouldn't the name contain 'stor'? */
 211                 debugf("RESTART ENUM\n");
 212
 213                 /* net device enumeration first */
 214                 if (dev_enum_net(di))
 215                         return 0;
 216         }
 217
 218         /*
 219          * The hidden assumption is there can only be one active network
 220          * device and it is identified upon enumeration (re)start, so there's
 221          * no point in trying to find network devices in other cases than the
 222          * (re)start and hence the 'next' device can only be storage
 223          */
 224         if (!dev_enum_storage(di))
 225                 /* make sure we mark there are no more devices */
 226                 di->cookie = NULL;
 227
 228         return 0;
 229 }
 230
 231
 232 static int API_dev_open(va_list ap)
 233 {
 234         struct device_info *di;
 235         int err = 0;
 236
 237         /* arg is ptr to the device_info struct */
 238         di = (struct device_info *)va_arg(ap, uintptr_t);
 239         if (di == NULL)
 240                 return API_EINVAL;
 241
 242         /* Allow only one consumer of the device at a time */
 243         if (di->state == DEV_STA_OPEN)
 244                 return API_EBUSY;
 245
 246         if (di->cookie == NULL)
 247                 return API_ENODEV;
 248
 249         if (di->type & DEV_TYP_STOR)
 250                 err = dev_open_stor(di->cookie);
 251
 252         else if (di->type & DEV_TYP_NET)
 253                 err = dev_open_net(di->cookie);
 254         else
 255                 err = API_ENODEV;
 256
 257         if (!err)
 258                 di->state = DEV_STA_OPEN;
 259
 260         return err;
 261 }
 262
 263
 264 static int API_dev_close(va_list ap)
 265 {
 266         struct device_info *di;
 267         int err = 0;
 268
 269         /* arg is ptr to the device_info struct */
 270         di = (struct device_info *)va_arg(ap, uintptr_t);
 271         if (di == NULL)
 272                 return API_EINVAL;
 273
 274         if (di->state == DEV_STA_CLOSED)
 275                 return 0;
 276
 277         if (di->cookie == NULL)
 278                 return API_ENODEV;
 279
 280         if (di->type & DEV_TYP_STOR)
 281                 err = dev_close_stor(di->cookie);
 282
 283         else if (di->type & DEV_TYP_NET)
 284                 err = dev_close_net(di->cookie);
 285         else
 286                 /*
 287                  * In case of unknown device we cannot change its state, so
 288                  * only return error code
 289                  */
 290                 err = API_ENODEV;
 291
 292         if (!err)
 293                 di->state = DEV_STA_CLOSED;
 294
 295         return err;
 296 }
 297
 298
 299 /*
 300  * pseudo signature:
 301  *
 302  * int API_dev_write(
 303  *      struct device_info *di,
 304  *      void *buf,
 305  *      int *len,
 306  *      unsigned long *start
 307  * )
 308  *
 309  * buf: ptr to buffer from where to get the data to send
 310  *
 311  * len: ptr to length to be read
 312  *      - network: len of packet to be sent (in bytes)
 313  *      - storage: # of blocks to write (can vary in size depending on define)
 314  *
 315  * start: ptr to start block (only used for storage devices, ignored for
 316  *        network)
 317  */
 318 static int API_dev_write(va_list ap)
 319 {
 320         struct device_info *di;
 321         void *buf;
 322         lbasize_t *len_stor, act_len_stor;
 323         lbastart_t *start;
 324         int *len_net;
 325         int err = 0;
 326
 327         /* 1. arg is ptr to the device_info struct */
 328         di = (struct device_info *)va_arg(ap, uintptr_t);
 329         if (di == NULL)
 330                 return API_EINVAL;
 331
 332         /* XXX should we check if device is open? i.e. the ->state ? */
 333
 334         if (di->cookie == NULL)
 335                 return API_ENODEV;
 336
 337         /* 2. arg is ptr to buffer from where to get data to write */
 338         buf = (void *)va_arg(ap, uintptr_t);
 339         if (buf == NULL)
 340                 return API_EINVAL;
 341
 342         if (di->type & DEV_TYP_STOR) {
 343                 /* 3. arg - ptr to var with # of blocks to write */
 344                 len_stor = (lbasize_t *)va_arg(ap, uintptr_t);
 345                 if (!len_stor)
 346                         return API_EINVAL;
 347                 if (*len_stor <= 0)
 348                         return API_EINVAL;
 349
 350                 /* 4. arg - ptr to var with start block */
 351                 start = (lbastart_t *)va_arg(ap, uintptr_t);
 352
 353                 act_len_stor = dev_write_stor(di->cookie, buf, *len_stor, *start);
 354                 if (act_len_stor != *len_stor) {
 355                         debugf("write @ %llu: done %llu out of %llu blocks",
 356                                    (uint64_t)blk, (uint64_t)act_len_stor,
 357                                    (uint64_t)len_stor);
 358                         return API_EIO;
 359                 }
 360
 361         } else if (di->type & DEV_TYP_NET) {
 362                 /* 3. arg points to the var with length of packet to write */
 363                 len_net = (int *)va_arg(ap, uintptr_t);
 364                 if (!len_net)
 365                         return API_EINVAL;
 366                 if (*len_net <= 0)
 367                         return API_EINVAL;
 368
 369                 err = dev_write_net(di->cookie, buf, *len_net);
 370
 371         } else
 372                 err = API_ENODEV;
 373
 374         return err;
 375 }
 376
 377
 378 /*
 379  * pseudo signature:
 380  *
 381  * int API_dev_read(
 382  *      struct device_info *di,
 383  *      void *buf,
 384  *      size_t *len,
 385  *      unsigned long *start
 386  *      size_t *act_len
 387  * )
 388  *
 389  * buf: ptr to buffer where to put the read data
 390  *
 391  * len: ptr to length to be read
 392  *      - network: len of packet to read (in bytes)
 393  *      - storage: # of blocks to read (can vary in size depending on define)
 394  *
 395  * start: ptr to start block (only used for storage devices, ignored for
 396  *        network)
 397  *
 398  * act_len: ptr to where to put the len actually read
 399  */
 400 static int API_dev_read(va_list ap)
 401 {
 402         struct device_info *di;
 403         void *buf;
 404         lbasize_t *len_stor, *act_len_stor;
 405         lbastart_t *start;
 406         int *len_net, *act_len_net;
 407
 408         /* 1. arg is ptr to the device_info struct */
 409         di = (struct device_info *)va_arg(ap, uintptr_t);
 410         if (di == NULL)
 411                 return API_EINVAL;
 412
 413         /* XXX should we check if device is open? i.e. the ->state ? */
 414
 415         if (di->cookie == NULL)
 416                 return API_ENODEV;
 417
 418         /* 2. arg is ptr to buffer from where to put the read data */
 419         buf = (void *)va_arg(ap, uintptr_t);
 420         if (buf == NULL)
 421                 return API_EINVAL;
 422
 423         if (di->type & DEV_TYP_STOR) {
 424                 /* 3. arg - ptr to var with # of blocks to read */
 425                 len_stor = (lbasize_t *)va_arg(ap, uintptr_t);
 426                 if (!len_stor)
 427                         return API_EINVAL;
 428                 if (*len_stor <= 0)
 429                         return API_EINVAL;
 430
 431                 /* 4. arg - ptr to var with start block */
 432                 start = (lbastart_t *)va_arg(ap, uintptr_t);
 433
 434                 /* 5. arg - ptr to var where to put the len actually read */
 435                 act_len_stor = (lbasize_t *)va_arg(ap, uintptr_t);
 436                 if (!act_len_stor)
 437                         return API_EINVAL;
 438
 439                 *act_len_stor = dev_read_stor(di->cookie, buf, *len_stor, *start);
 440
 441         } else if (di->type & DEV_TYP_NET) {
 442
 443                 /* 3. arg points to the var with length of packet to read */
 444                 len_net = (int *)va_arg(ap, uintptr_t);
 445                 if (!len_net)
 446                         return API_EINVAL;
 447                 if (*len_net <= 0)
 448                         return API_EINVAL;
 449
 450                 /* 4. - ptr to var where to put the len actually read */
 451                 act_len_net = (int *)va_arg(ap, uintptr_t);
 452                 if (!act_len_net)
 453                         return API_EINVAL;
 454
 455                 *act_len_net = dev_read_net(di->cookie, buf, *len_net);
 456
 457         } else
 458                 return API_ENODEV;
 459
 460         return 0;
 461 }
 462
 463
 464 /*
 465  * pseudo signature:
 466  *
 467  * int API_env_get(const char *name, char **value)
 468  *
 469  * name: ptr to name of env var
 470  */
 471 static int API_env_get(va_list ap)
 472 {
 473         char *name, **value;
 474
 475         if ((name = (char *)va_arg(ap, uintptr_t)) == NULL)
 476                 return API_EINVAL;
 477         if ((value = (char **)va_arg(ap, uintptr_t)) == NULL)
 478                 return API_EINVAL;
 479
 480         *value = env_get(name);
 481
 482         return 0;
 483 }
 484
 485 /*
 486  * pseudo signature:
 487  *
 488  * int API_env_set(const char *name, const char *value)
 489  *
 490  * name: ptr to name of env var
 491  *
 492  * value: ptr to value to be set
 493  */
 494 static int API_env_set(va_list ap)
 495 {
 496         char *name, *value;
 497
 498         if ((name = (char *)va_arg(ap, uintptr_t)) == NULL)
 499                 return API_EINVAL;
 500         if ((value = (char *)va_arg(ap, uintptr_t)) == NULL)
 501                 return API_EINVAL;
 502
 503         env_set(name, value);
 504
 505         return 0;
 506 }
 507
 508 /*
 509  * pseudo signature:
 510  *
 511  * int API_env_enum(const char *last, char **next)
 512  *
 513  * last: ptr to name of env var found in last iteration
 514  */
 515 static int API_env_enum(va_list ap)
 516 {
 517         int i, buflen;
 518         char *last, **next, *s;
 519         struct env_entry *match, search;
 520         static char *var;
 521
 522         last = (char *)va_arg(ap, unsigned long);
 523
 524         if ((next = (char **)va_arg(ap, uintptr_t)) == NULL)
 525                 return API_EINVAL;
 526
 527         if (last == NULL) {
 528                 var = NULL;
 529                 i = 0;
 530         } else {
 531                 var = strdup(last);
 532                 s = strchr(var, '=');
 533                 if (s != NULL)
 534                         *s = 0;
 535                 search.key = var;
 536                 i = hsearch_r(search, ENV_FIND, &match, &env_htab, 0);
 537                 if (i == 0) {
 538                         i = API_EINVAL;
 539                         goto done;
 540                 }
 541         }
 542
 543         /* match the next entry after i */
 544         i = hmatch_r("", i, &match, &env_htab);
 545         if (i == 0)
 546                 goto done;
 547         buflen = strlen(match->key) + strlen(match->data) + 2;
 548         var = realloc(var, buflen);
 549         snprintf(var, buflen, "%s=%s", match->key, match->data);
 550         *next = var;
 551         return 0;
 552
 553 done:
 554         free(var);
 555         var = NULL;
 556         *next = NULL;
 557         return i;
 558 }
 559
 560 /*
 561  * pseudo signature:
 562  *
 563  * int API_display_get_info(int type, struct display_info *di)
 564  */
 565 static int API_display_get_info(va_list ap)
 566 {
 567         int type;
 568         struct display_info *di;
 569
 570         type = va_arg(ap, int);
 571         di = va_arg(ap, struct display_info *);
 572
 573         return display_get_info(type, di);
 574 }
 575
 576 /*
 577  * pseudo signature:
 578  *
 579  * int API_display_draw_bitmap(ulong bitmap, int x, int y)
 580  */
 581 static int API_display_draw_bitmap(va_list ap)
 582 {
 583         ulong bitmap;
 584         int x, y;
 585
 586         bitmap = va_arg(ap, ulong);
 587         x = va_arg(ap, int);
 588         y = va_arg(ap, int);
 589
 590         return display_draw_bitmap(bitmap, x, y);
 591 }
 592
 593 /*
 594  * pseudo signature:
 595  *
 596  * void API_display_clear(void)
 597  */
 598 static int API_display_clear(va_list ap)
 599 {
 600         display_clear();
 601         return 0;
 602 }
 603
 604 static cfp_t calls_table[API_MAXCALL] = { NULL, };
 605
 606 /*
 607  * The main syscall entry point - this is not reentrant, only one call is
 608  * serviced until finished.
 609  *
 610  * e.g. syscall(1, int *, u_int32_t, u_int32_t, u_int32_t, u_int32_t);
 611  *
 612  * call:        syscall number
 613  *
 614  * retval:      points to the return value placeholder, this is the place the
 615  *              syscall puts its return value, if NULL the caller does not
 616  *              expect a return value
 617  *
 618  * ...          syscall arguments (variable number)
 619  *
 620  * returns:     0 if the call not found, 1 if serviced
 621  */
 622 int syscall(int call, int *retval, ...)
 623 {
 624         va_list ap;
 625         int rv;
 626
 627         if (call < 0 || call >= calls_no) {
 628                 debugf("invalid call #%d\n", call);
 629                 return 0;
 630         }
 631
 632         if (calls_table[call] == NULL) {
 633                 debugf("syscall #%d does not have a handler\n", call);
 634                 return 0;
 635         }
 636
 637         va_start(ap, retval);
 638         rv = calls_table[call](ap);
 639         if (retval != NULL)
 640                 *retval = rv;
 641
 642         return 1;
 643 }
 644
 645 int api_init(void)
 646 {
 647         struct api_signature *sig;
 648
 649         /* TODO put this into linker set one day... */
 650         calls_table[API_RSVD] = NULL;
 651         calls_table[API_GETC] = &API_getc;
 652         calls_table[API_PUTC] = &API_putc;
 653         calls_table[API_TSTC] = &API_tstc;
 654         calls_table[API_PUTS] = &API_puts;
 655         calls_table[API_RESET] = &API_reset;
 656         calls_table[API_GET_SYS_INFO] = &API_get_sys_info;
 657         calls_table[API_UDELAY] = &API_udelay;
 658         calls_table[API_GET_TIMER] = &API_get_timer;
 659         calls_table[API_DEV_ENUM] = &API_dev_enum;
 660         calls_table[API_DEV_OPEN] = &API_dev_open;
 661         calls_table[API_DEV_CLOSE] = &API_dev_close;
 662         calls_table[API_DEV_READ] = &API_dev_read;
 663         calls_table[API_DEV_WRITE] = &API_dev_write;
 664         calls_table[API_ENV_GET] = &API_env_get;
 665         calls_table[API_ENV_SET] = &API_env_set;
 666         calls_table[API_ENV_ENUM] = &API_env_enum;
 667         calls_table[API_DISPLAY_GET_INFO] = &API_display_get_info;
 668         calls_table[API_DISPLAY_DRAW_BITMAP] = &API_display_draw_bitmap;
 669         calls_table[API_DISPLAY_CLEAR] = &API_display_clear;
 670         calls_no = API_MAXCALL;
 671
 672         debugf("API initialized with %d calls\n", calls_no);
 673
 674         dev_stor_init();
 675
 676         /*
 677          * Produce the signature so the API consumers can find it
 678          */
 679         sig = malloc(sizeof(struct api_signature));
 680         if (sig == NULL) {
 681                 printf("API: could not allocate memory for the signature!\n");
 682                 return -ENOMEM;
 683         }
 684
 685         env_set_hex("api_address", (unsigned long)sig);
 686         debugf("API sig @ 0x%lX\n", (unsigned long)sig);
 687         memcpy(sig->magic, API_SIG_MAGIC, 8);
 688         sig->version = API_SIG_VERSION;
 689         sig->syscall = &syscall;
 690         sig->checksum = 0;
 691         sig->checksum = crc32(0, (unsigned char *)sig,
 692                               sizeof(struct api_signature));
 693         debugf("syscall entry: 0x%lX\n", (unsigned long)sig->syscall);
 694
 695         return 0;
 696 }
 697
 698 void platform_set_mr(struct sys_info *si, unsigned long start, unsigned long size,
 699                         int flags)
 700 {
 701         int i;
 702
 703         if (!si->mr || !size || (flags == 0))
 704                 return;
 705
 706         /* find free slot */
 707         for (i = 0; i < si->mr_no; i++)
 708                 if (si->mr[i].flags == 0) {
 709                         /* insert new mem region */
 710                         si->mr[i].start = start;
 711                         si->mr[i].size = size;
 712                         si->mr[i].flags = flags;
 713                         return;
 714                 }
 715 }