common/env_dataflash.c

   1 /*
   2  * LowLevel function for DataFlash environment support
   3  * Author : Gilles Gastaldi (Atmel)
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7 #include <common.h>
   8 #include <command.h>
   9 #include <environment.h>
  10 #include <linux/stddef.h>
  11 #include <dataflash.h>
  12 #include <search.h>
  13 #include <errno.h>
  14
  15 DECLARE_GLOBAL_DATA_PTR;
  16
  17 env_t *env_ptr;
  18
  19 char *env_name_spec = "dataflash";
  20
  21 uchar env_get_char_spec(int index)
  22 {
  23         uchar c;
  24
  25         read_dataflash(CONFIG_ENV_ADDR + index + offsetof(env_t, data),
  26                         1, (char *)&c);
  27         return c;
  28 }
  29
  30 void env_relocate_spec(void)
  31 {
  32         char buf[CONFIG_ENV_SIZE];
  33
  34         read_dataflash(CONFIG_ENV_ADDR, CONFIG_ENV_SIZE, buf);
  35
  36         env_import(buf, 1);
  37 }
  38
  39 #ifdef CONFIG_ENV_OFFSET_REDUND
  40 #error No support for redundant environment on dataflash yet!
  41 #endif
  42
  43 int saveenv(void)
  44 {
  45         env_t   env_new;
  46         ssize_t len;
  47         char    *res;
  48
  49         res = (char *)&env_new.data;
  50         len = hexport_r(&env_htab, '\0', 0, &res, ENV_SIZE, 0, NULL);
  51         if (len < 0) {
  52                 error("Cannot export environment: errno = %d\n", errno);
  53                 return 1;
  54         }
  55         env_new.crc = crc32(0, env_new.data, ENV_SIZE);
  56
  57         return write_dataflash(CONFIG_ENV_ADDR,
  58                                 (unsigned long)&env_new,
  59                                 CONFIG_ENV_SIZE);
  60 }
  61
  62 /*
  63  * Initialize environment use
  64  *
  65  * We are still running from ROM, so data use is limited.
  66  * Use a (moderately small) buffer on the stack
  67  */
  68 int env_init(void)
  69 {
  70         ulong crc, len = ENV_SIZE, new = 0;
  71         unsigned off;
  72         uchar buf[64];
  73
  74         if (gd->env_valid)
  75                 return 0;
  76
  77         AT91F_DataflashInit();  /* prepare for DATAFLASH read/write */
  78
  79         /* read old CRC */
  80         read_dataflash(CONFIG_ENV_ADDR + offsetof(env_t, crc),
  81                 sizeof(ulong), (char *)&crc);
  82
  83         off = offsetof(env_t, data);
  84         while (len > 0) {
  85                 int n = (len > sizeof(buf)) ? sizeof(buf) : len;
  86
  87                 read_dataflash(CONFIG_ENV_ADDR + off, n, (char *)buf);
  88
  89                 new = crc32(new, buf, n);
  90                 len -= n;
  91                 off += n;
  92         }
  93
  94         if (crc == new) {
  95                 gd->env_addr    = offsetof(env_t, data);
  96                 gd->env_valid   = 1;
  97         } else {
  98                 gd->env_addr    = (ulong)&default_environment[0];
  99                 gd->env_valid   = 0;
 100         }
 101
 102         return 0;
 103 }