LXR uboot/env/nvram.c

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * (C) Copyright 2000-2010
   4 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   5 *
   6 * (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
   7 * Andreas Heppel <aheppel@sysgo.de>
   8 */
   9
  10/*
  11 * 09-18-2001 Andreas Heppel, Sysgo RTS GmbH <aheppel@sysgo.de>
  12 *
  13 * It might not be possible in all cases to use 'memcpy()' to copy
  14 * the environment to NVRAM, as the NVRAM might not be mapped into
  15 * the memory space. (I.e. this is the case for the BAB750). In those
  16 * cases it might be possible to access the NVRAM using a different
  17 * method. For example, the RTC on the BAB750 is accessible in IO
  18 * space using its address and data registers. To enable usage of
  19 * NVRAM in those cases I invented the functions 'nvram_read()' and
  20 * 'nvram_write()', which will be activated upon the configuration
  21 * #define CONFIG_SYS_NVRAM_ACCESS_ROUTINE. Note, that those functions are
  22 * strongly dependent on the used HW, and must be redefined for each
  23 * board that wants to use them.
  24 */
  25
  26#include <common.h>
  27#include <command.h>
  28#include <env.h>
  29#include <env_internal.h>
  30#include <asm/global_data.h>
  31#include <linux/stddef.h>
  32#include <search.h>
  33#include <errno.h>
  34#include <u-boot/crc.h>
  35
  36DECLARE_GLOBAL_DATA_PTR;
  37
  38#ifdef CONFIG_SYS_NVRAM_ACCESS_ROUTINE
  39extern void *nvram_read(void *dest, const long src, size_t count);
  40extern void nvram_write(long dest, const void *src, size_t count);
  41#else
  42static env_t *env_ptr = (env_t *)CONFIG_ENV_ADDR;
  43#endif
  44
  45static int env_nvram_load(void)
  46{
  47        char buf[CONFIG_ENV_SIZE];
  48
  49#if defined(CONFIG_SYS_NVRAM_ACCESS_ROUTINE)
  50        nvram_read(buf, CONFIG_ENV_ADDR, CONFIG_ENV_SIZE);
  51#else
  52        memcpy(buf, (void *)CONFIG_ENV_ADDR, CONFIG_ENV_SIZE);
  53#endif
  54        return env_import(buf, 1, H_EXTERNAL);
  55}
  56
  57static int env_nvram_save(void)
  58{
  59        env_t   env_new;
  60        int     rcode = 0;
  61
  62        rcode = env_export(&env_new);
  63        if (rcode)
  64                return rcode;
  65
  66#ifdef CONFIG_SYS_NVRAM_ACCESS_ROUTINE
  67        nvram_write(CONFIG_ENV_ADDR, &env_new, CONFIG_ENV_SIZE);
  68#else
  69        if (memcpy((char *)CONFIG_ENV_ADDR, &env_new, CONFIG_ENV_SIZE) == NULL)
  70                rcode = 1;
  71#endif
  72        return rcode;
  73}
  74
  75/*
  76 * Initialize Environment use
  77 *
  78 * We are still running from ROM, so data use is limited
  79 */
  80static int env_nvram_init(void)
  81{
  82#if defined(CONFIG_SYS_NVRAM_ACCESS_ROUTINE)
  83        ulong crc;
  84        uchar data[ENV_SIZE];
  85
  86        nvram_read(&crc, CONFIG_ENV_ADDR, sizeof(ulong));
  87        nvram_read(data, CONFIG_ENV_ADDR + sizeof(ulong), ENV_SIZE);
  88
  89        if (crc32(0, data, ENV_SIZE) == crc) {
  90                gd->env_addr = (ulong)CONFIG_ENV_ADDR + sizeof(long);
  91#else
  92        if (crc32(0, env_ptr->data, ENV_SIZE) == env_ptr->crc) {
  93                gd->env_addr = (ulong)&env_ptr->data;
  94#endif
  95                gd->env_valid = ENV_VALID;
  96        } else {
  97                gd->env_valid = ENV_INVALID;
  98        }
  99
 100        return 0;
 101}
 102
 103U_BOOT_ENV_LOCATION(nvram) = {
 104        .location       = ENVL_NVRAM,
 105        ENV_NAME("NVRAM")
 106        .load           = env_nvram_load,
 107        .save           = env_save_ptr(env_nvram_save),
 108        .init           = env_nvram_init,
 109};
 110