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
  64         if (sig == NULL)
  65                 return 0;
  66
  67         sp = (unsigned char *)API_SEARCH_START;
  68
  69         while ((sp + (int)API_SIG_MAGLEN) < (unsigned char *)API_SEARCH_END) {
  70                 if (!memcmp(sp, API_SIG_MAGIC, API_SIG_MAGLEN)) {
  71                         *sig = (struct api_signature *)sp;
  72                         if (valid_sig(*sig))
  73                                 return 1;
  74                 }
  75                 sp += API_SIG_MAGLEN;
  76         }
  77
  78         *sig = NULL;
  79         return 0;
  80 }
  81
  82 /****************************************
  83  *
  84  * console
  85  *
  86  ****************************************/
  87
  88 int ub_getc(void)
  89 {
  90         int c;
  91
  92         if (!syscall(API_GETC, NULL, (uint32_t)&c))
  93                 return -1;
  94
  95         return c;
  96 }
  97
  98 int ub_tstc(void)
  99 {
 100         int t;
 101
 102         if (!syscall(API_TSTC, NULL, (uint32_t)&t))
 103                 return -1;
 104
 105         return t;
 106 }
 107
 108 void ub_putc(char c)
 109 {
 110         syscall(API_PUTC, NULL, (uint32_t)&c);
 111 }
 112
 113 void ub_puts(const char *s)
 114 {
 115         syscall(API_PUTS, NULL, (uint32_t)s);
 116 }
 117
 118 /****************************************
 119  *
 120  * system
 121  *
 122  ****************************************/
 123
 124 void ub_reset(void)
 125 {
 126         syscall(API_RESET, NULL);
 127 }
 128
 129 #define MR_MAX 5
 130 static struct mem_region mr[MR_MAX];
 131 static struct sys_info si;
 132
 133 struct sys_info * ub_get_sys_info(void)
 134 {
 135         int err = 0;
 136
 137         memset(&si, 0, sizeof(struct sys_info));
 138         si.mr = mr;
 139         si.mr_no = MR_MAX;
 140         memset(&mr, 0, sizeof(mr));
 141
 142         if (!syscall(API_GET_SYS_INFO, &err, (u_int32_t)&si))
 143                 return NULL;
 144
 145         return ((err) ? NULL : &si);
 146 }
 147
 148 /****************************************
 149  *
 150  * timing
 151  *
 152  ****************************************/
 153
 154 void ub_udelay(unsigned long usec)
 155 {
 156         syscall(API_UDELAY, NULL, &usec);
 157 }
 158
 159 unsigned long ub_get_timer(unsigned long base)
 160 {
 161         unsigned long cur;
 162
 163         if (!syscall(API_GET_TIMER, NULL, &cur, &base))
 164                 return 0;
 165
 166         return cur;
 167 }
 168
 169
 170 /****************************************************************************
 171  *
 172  * devices
 173  *
 174  * Devices are identified by handles: numbers 0, 1, 2, ..., MAX_DEVS-1
 175  *
 176  ***************************************************************************/
 177
 178 #define MAX_DEVS 6
 179
 180 static struct device_info devices[MAX_DEVS];
 181
 182 struct device_info * ub_dev_get(int i)
 183 {
 184         return ((i < 0 || i >= MAX_DEVS) ? NULL : &devices[i]);
 185 }
 186
 187 /*
 188  * Enumerates the devices: fills out device_info elements in the devices[]
 189  * array.
 190  *
 191  * returns:             number of devices found
 192  */
 193 int ub_dev_enum(void)
 194 {
 195         struct device_info *di;
 196         int n = 0;
 197
 198         memset(&devices, 0, sizeof(struct device_info) * MAX_DEVS);
 199         di = &devices[0];
 200
 201         if (!syscall(API_DEV_ENUM, NULL, di))
 202                 return 0;
 203
 204         while (di->cookie != NULL) {
 205
 206                 if (++n >= MAX_DEVS)
 207                         break;
 208
 209                 /* take another device_info */
 210                 di++;
 211
 212                 /* pass on the previous cookie */
 213                 di->cookie = devices[n - 1].cookie;
 214
 215                 if (!syscall(API_DEV_ENUM, NULL, di))
 216                         return 0;
 217         }
 218
 219         return n;
 220 }
 221
 222 /*
 223  * handle:      0-based id of the device
 224  *
 225  * returns:     0 when OK, err otherwise
 226  */
 227 int ub_dev_open(int handle)
 228 {
 229         struct device_info *di;
 230         int err = 0;
 231
 232         if (handle < 0 || handle >= MAX_DEVS)
 233                 return API_EINVAL;
 234
 235         di = &devices[handle];
 236
 237         if (!syscall(API_DEV_OPEN, &err, di))
 238                 return -1;
 239
 240         return err;
 241 }
 242
 243 int ub_dev_close(int handle)
 244 {
 245         struct device_info *di;
 246
 247         if (handle < 0 || handle >= MAX_DEVS)
 248                 return API_EINVAL;
 249
 250         di = &devices[handle];
 251         if (!syscall(API_DEV_CLOSE, NULL, di))
 252                 return -1;
 253
 254         return 0;
 255 }
 256
 257 /*
 258  *
 259  * Validates device for read/write, it has to:
 260  *
 261  * - have sane handle
 262  * - be opened
 263  *
 264  * returns:     0/1 accordingly
 265  */
 266 static int dev_valid(int handle)
 267 {
 268         if (handle < 0 || handle >= MAX_DEVS)
 269                 return 0;
 270
 271         if (devices[handle].state != DEV_STA_OPEN)
 272                 return 0;
 273
 274         return 1;
 275 }
 276
 277 static int dev_stor_valid(int handle)
 278 {
 279         if (!dev_valid(handle))
 280                 return 0;
 281
 282         if (!(devices[handle].type & DEV_TYP_STOR))
 283                 return 0;
 284
 285         return 1;
 286 }
 287
 288 int ub_dev_read(int handle, void *buf, lbasize_t len, lbastart_t start)
 289 {
 290         struct device_info *di;
 291         lbasize_t act_len;
 292         int err = 0;
 293
 294         if (!dev_stor_valid(handle))
 295                 return API_ENODEV;
 296
 297         di = &devices[handle];
 298         if (!syscall(API_DEV_READ, &err, di, buf, &len, &start, &act_len))
 299                 return -1;
 300
 301         if (err)
 302                 return err;
 303
 304         if (act_len != len)
 305                 return API_EIO;
 306
 307         return 0;
 308 }
 309
 310 static int dev_net_valid(int handle)
 311 {
 312         if (!dev_valid(handle))
 313                 return 0;
 314
 315         if (devices[handle].type != DEV_TYP_NET)
 316                 return 0;
 317
 318         return 1;
 319 }
 320
 321 int ub_dev_recv(int handle, void *buf, int len)
 322 {
 323         struct device_info *di;
 324         int err = 0, act_len;
 325
 326         if (!dev_net_valid(handle))
 327                 return API_ENODEV;
 328
 329         di = &devices[handle];
 330         if (!syscall(API_DEV_READ, &err, di, buf, &len, &act_len))
 331                 return -1;
 332
 333         if (err)
 334                 return -1;
 335
 336         return act_len;
 337 }
 338
 339 int ub_dev_send(int handle, void *buf, int len)
 340 {
 341         struct device_info *di;
 342         int err = 0;
 343
 344         if (!dev_net_valid(handle))
 345                 return API_ENODEV;
 346
 347         di = &devices[handle];
 348         if (!syscall(API_DEV_WRITE, &err, di, buf, &len))
 349                 return -1;
 350
 351         return err;
 352 }
 353
 354 /****************************************
 355  *
 356  * env vars
 357  *
 358  ****************************************/
 359
 360 char * ub_env_get(const char *name)
 361 {
 362         char *value;
 363
 364         if (!syscall(API_ENV_GET, NULL, (uint32_t)name, (uint32_t)&value))
 365                 return NULL;
 366
 367         return value;
 368 }
 369
 370 void ub_env_set(const char *name, char *value)
 371 {
 372         syscall(API_ENV_SET, NULL, (uint32_t)name, (uint32_t)value);
 373 }
 374
 375
 376 static char env_name[256];
 377
 378 const char * ub_env_enum(const char *last)
 379 {
 380         const char *env, *str;
 381         int i;
 382
 383         env = NULL;
 384
 385         /*
 386          * It's OK to pass only the name piece as last (and not the whole
 387          * 'name=val' string), since the API_ENUM_ENV call uses envmatch()
 388          * internally, which handles such case
 389          */
 390         if (!syscall(API_ENV_ENUM, NULL, (uint32_t)last, (uint32_t)&env))
 391                 return NULL;
 392
 393         if (!env)
 394                 /* no more env. variables to enumerate */
 395                 return NULL;
 396
 397         /* next enumerated env var */
 398         memset(env_name, 0, 256);
 399         for (i = 0, str = env; *str != '=' && *str != '\0';)
 400                 env_name[i++] = *str++;
 401
 402         env_name[i] = '\0';
 403
 404         return env_name;
 405 }