api_examples/glue.c

   1 /*
   2  * (C) Copyright 2007 Semihalf
   3  *
   4  * Written by: Rafal Jaworowski <raj@semihalf.com>
   5  *
   6  * See file CREDITS for list of people who contributed to this
   7  * project.
   8  *
   9  * This program is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License as
  11  * published by the Free Software Foundation; either version 2 of
  12  * the License, or (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  22  * MA 02111-1307 USA
  23  *
  24  */
  25
  26 #include <common.h>
  27 #include <linux/types.h>
  28 #include <api_public.h>
  29
  30 #include "glue.h"
  31
  32 static int valid_sig(struct api_signature *sig)
  33 {
  34         uint32_t checksum;
  35         struct api_signature s;
  36
  37         if (sig == NULL)
  38                 return 0;
  39         /*
  40          * Clear the checksum field (in the local copy) so as to calculate the
  41          * CRC with the same initial contents as at the time when the sig was
  42          * produced
  43          */
  44         s = *sig;
  45         s.checksum = 0;
  46
  47         checksum = crc32(0, (unsigned char *)&s, sizeof(struct api_signature));
  48
  49         if (checksum != sig->checksum)
  50                 return 0;
  51
  52         return 1;
  53 }
  54
  55 /*
  56  * Searches for the U-Boot API signature
  57  *
  58  * returns 1/0 depending on found/not found result
  59  */
  60 int api_search_sig(struct api_signature **sig) {
  61
  62         unsigned char *sp;
  63         uint32_t search_start = 0;
  64         uint32_t search_end = 0;
  65
  66         if (sig == NULL)
  67                 return 0;
  68
  69         if (search_hint == 0)
  70                 search_hint = 255 * 1024 * 1024;
  71
  72         search_start = search_hint & ~0x000fffff;
  73         search_end = search_start + API_SEARCH_LEN - API_SIG_MAGLEN;
  74
  75         sp = (unsigned char *)search_start;
  76         while ((sp + API_SIG_MAGLEN) < (unsigned char *)search_end) {
  77                 if (!memcmp(sp, API_SIG_MAGIC, API_SIG_MAGLEN)) {
  78                         *sig = (struct api_signature *)sp;
  79                         if (valid_sig(*sig))
  80                                 return 1;
  81                 }
  82                 sp += API_SIG_MAGLEN;
  83         }
  84
  85         *sig = NULL;
  86         return 0;
  87 }
  88
  89 /****************************************
  90  *
  91  * console
  92  *
  93  ****************************************/
  94
  95 int ub_getc(void)
  96 {
  97         int c;
  98
  99         if (!syscall(API_GETC, NULL, (uint32_t)&c))
 100                 return -1;
 101
 102         return c;
 103 }
 104
 105 int ub_tstc(void)
 106 {
 107         int t;
 108
 109         if (!syscall(API_TSTC, NULL, (uint32_t)&t))
 110                 return -1;
 111
 112         return t;
 113 }
 114
 115 void ub_putc(char c)
 116 {
 117         syscall(API_PUTC, NULL, (uint32_t)&c);
 118 }
 119
 120 void ub_puts(const char *s)
 121 {
 122         syscall(API_PUTS, NULL, (uint32_t)s);
 123 }
 124
 125 /****************************************
 126  *
 127  * system
 128  *
 129  ****************************************/
 130
 131 void ub_reset(void)
 132 {
 133         syscall(API_RESET, NULL);
 134 }
 135
 136 #define MR_MAX 5
 137 static struct mem_region mr[MR_MAX];
 138 static struct sys_info si;
 139
 140 struct sys_info * ub_get_sys_info(void)
 141 {
 142         int err = 0;
 143
 144         memset(&si, 0, sizeof(struct sys_info));
 145         si.mr = mr;
 146         si.mr_no = MR_MAX;
 147         memset(&mr, 0, sizeof(mr));
 148
 149         if (!syscall(API_GET_SYS_INFO, &err, (u_int32_t)&si))
 150                 return NULL;
 151
 152         return ((err) ? NULL : &si);
 153 }
 154
 155 /****************************************
 156  *
 157  * timing
 158  *
 159  ****************************************/
 160
 161 void ub_udelay(unsigned long usec)
 162 {
 163         syscall(API_UDELAY, NULL, &usec);
 164 }
 165
 166 unsigned long ub_get_timer(unsigned long base)
 167 {
 168         unsigned long cur;
 169
 170         if (!syscall(API_GET_TIMER, NULL, &cur, &base))
 171                 return 0;
 172
 173         return cur;
 174 }
 175
 176
 177 /****************************************************************************
 178  *
 179  * devices
 180  *
 181  * Devices are identified by handles: numbers 0, 1, 2, ..., MAX_DEVS-1
 182  *
 183  ***************************************************************************/
 184
 185 #define MAX_DEVS 6
 186
 187 static struct device_info devices[MAX_DEVS];
 188
 189 struct device_info * ub_dev_get(int i)
 190 {
 191         return ((i < 0 || i >= MAX_DEVS) ? NULL : &devices[i]);
 192 }
 193
 194 /*
 195  * Enumerates the devices: fills out device_info elements in the devices[]
 196  * array.
 197  *
 198  * returns:             number of devices found
 199  */
 200 int ub_dev_enum(void)
 201 {
 202         struct device_info *di;
 203         int n = 0;
 204
 205         memset(&devices, 0, sizeof(struct device_info) * MAX_DEVS);
 206         di = &devices[0];
 207
 208         if (!syscall(API_DEV_ENUM, NULL, di))
 209                 return 0;
 210
 211         while (di->cookie != NULL) {
 212
 213                 if (++n >= MAX_DEVS)
 214                         break;
 215
 216                 /* take another device_info */
 217                 di++;
 218
 219                 /* pass on the previous cookie */
 220                 di->cookie = devices[n - 1].cookie;
 221
 222                 if (!syscall(API_DEV_ENUM, NULL, di))
 223                         return 0;
 224         }
 225
 226         return n;
 227 }
 228
 229 /*
 230  * handle:      0-based id of the device
 231  *
 232  * returns:     0 when OK, err otherwise
 233  */
 234 int ub_dev_open(int handle)
 235 {
 236         struct device_info *di;
 237         int err = 0;
 238
 239         if (handle < 0 || handle >= MAX_DEVS)
 240                 return API_EINVAL;
 241
 242         di = &devices[handle];
 243
 244         if (!syscall(API_DEV_OPEN, &err, di))
 245                 return -1;
 246
 247         return err;
 248 }
 249
 250 int ub_dev_close(int handle)
 251 {
 252         struct device_info *di;
 253
 254         if (handle < 0 || handle >= MAX_DEVS)
 255                 return API_EINVAL;
 256
 257         di = &devices[handle];
 258         if (!syscall(API_DEV_CLOSE, NULL, di))
 259                 return -1;
 260
 261         return 0;
 262 }
 263
 264 /*
 265  *
 266  * Validates device for read/write, it has to:
 267  *
 268  * - have sane handle
 269  * - be opened
 270  *
 271  * returns:     0/1 accordingly
 272  */
 273 static int dev_valid(int handle)
 274 {
 275         if (handle < 0 || handle >= MAX_DEVS)
 276                 return 0;
 277
 278         if (devices[handle].state != DEV_STA_OPEN)
 279                 return 0;
 280
 281         return 1;
 282 }
 283
 284 static int dev_stor_valid(int handle)
 285 {
 286         if (!dev_valid(handle))
 287                 return 0;
 288
 289         if (!(devices[handle].type & DEV_TYP_STOR))
 290                 return 0;
 291
 292         return 1;
 293 }
 294
 295 int ub_dev_read(int handle, void *buf, lbasize_t len, lbastart_t start)
 296 {
 297         struct device_info *di;
 298         lbasize_t act_len;
 299         int err = 0;
 300
 301         if (!dev_stor_valid(handle))
 302                 return API_ENODEV;
 303
 304         di = &devices[handle];
 305         if (!syscall(API_DEV_READ, &err, di, buf, &len, &start, &act_len))
 306                 return -1;
 307
 308         if (err)
 309                 return err;
 310
 311         if (act_len != len)
 312                 return API_EIO;
 313
 314         return 0;
 315 }
 316
 317 static int dev_net_valid(int handle)
 318 {
 319         if (!dev_valid(handle))
 320                 return 0;
 321
 322         if (devices[handle].type != DEV_TYP_NET)
 323                 return 0;
 324
 325         return 1;
 326 }
 327
 328 int ub_dev_recv(int handle, void *buf, int len)
 329 {
 330         struct device_info *di;
 331         int err = 0, act_len;
 332
 333         if (!dev_net_valid(handle))
 334                 return API_ENODEV;
 335
 336         di = &devices[handle];
 337         if (!syscall(API_DEV_READ, &err, di, buf, &len, &act_len))
 338                 return -1;
 339
 340         if (err)
 341                 return -1;
 342
 343         return act_len;
 344 }
 345
 346 int ub_dev_send(int handle, void *buf, int len)
 347 {
 348         struct device_info *di;
 349         int err = 0;
 350
 351         if (!dev_net_valid(handle))
 352                 return API_ENODEV;
 353
 354         di = &devices[handle];
 355         if (!syscall(API_DEV_WRITE, &err, di, buf, &len))
 356                 return -1;
 357
 358         return err;
 359 }
 360
 361 /****************************************
 362  *
 363  * env vars
 364  *
 365  ****************************************/
 366
 367 char * ub_env_get(const char *name)
 368 {
 369         char *value;
 370
 371         if (!syscall(API_ENV_GET, NULL, (uint32_t)name, (uint32_t)&value))
 372                 return NULL;
 373
 374         return value;
 375 }
 376
 377 void ub_env_set(const char *name, char *value)
 378 {
 379         syscall(API_ENV_SET, NULL, (uint32_t)name, (uint32_t)value);
 380 }
 381
 382
 383 static char env_name[256];
 384
 385 const char * ub_env_enum(const char *last)
 386 {
 387         const char *env, *str;
 388         int i;
 389
 390         env = NULL;
 391
 392         /*
 393          * It's OK to pass only the name piece as last (and not the whole
 394          * 'name=val' string), since the API_ENUM_ENV call uses envmatch()
 395          * internally, which handles such case
 396          */
 397         if (!syscall(API_ENV_ENUM, NULL, (uint32_t)last, (uint32_t)&env))
 398                 return NULL;
 399
 400         if (!env)
 401                 /* no more env. variables to enumerate */
 402                 return NULL;
 403
 404         /* next enumerated env var */
 405         memset(env_name, 0, 256);
 406         for (i = 0, str = env; *str != '=' && *str != '\0';)
 407                 env_name[i++] = *str++;
 408
 409         env_name[i] = '\0';
 410
 411         return env_name;
 412 }