/*

   * (C) Copyright 2008-2011 Freescale Semiconductor, Inc.

   *

   * SPDX-License-Identifier:	GPL-2.0+

   */
  
  /* #define DEBUG */
  
  #include <common.h>
  
  #include <command.h>
  #include <environment.h>
  #include <linux/stddef.h>
  #include <malloc.h>
  #include <mmc.h>

  #include <search.h>

  #include <errno.h>

  #if defined(CONFIG_ENV_SIZE_REDUND) &&  \
  	(CONFIG_ENV_SIZE_REDUND != CONFIG_ENV_SIZE)
  #error CONFIG_ENV_SIZE_REDUND should be the same as CONFIG_ENV_SIZE
  #endif

  char *env_name_spec = "MMC";
  
  #ifdef ENV_IS_EMBEDDED

  env_t *env_ptr = &environment;

  #else /* ! ENV_IS_EMBEDDED */

  env_t *env_ptr;

  #endif /* ENV_IS_EMBEDDED */

  DECLARE_GLOBAL_DATA_PTR;

  #if !defined(CONFIG_ENV_OFFSET)
  #define CONFIG_ENV_OFFSET 0
  #endif

  __weak int mmc_get_env_addr(struct mmc *mmc, int copy, u32 *env_addr)

  {

  	s64 offset;
  
  	offset = CONFIG_ENV_OFFSET;

  #ifdef CONFIG_ENV_OFFSET_REDUND
  	if (copy)

  		offset = CONFIG_ENV_OFFSET_REDUND;

  #endif

  
  	if (offset < 0)
  		offset += mmc->capacity;
  
  	*env_addr = offset;

  	return 0;
  }

  int env_init(void)
  {
  	/* use default */

  	gd->env_addr	= (ulong)&default_environment[0];
  	gd->env_valid	= 1;

  
  	return 0;
  }

  static int init_mmc_for_env(struct mmc *mmc)

  {
  	if (!mmc) {
  		puts("No MMC card found
  ");
  		return -1;
  	}
  
  	if (mmc_init(mmc)) {
  		puts("MMC init failed
  ");

  		return -1;

  	}

  #ifdef CONFIG_SYS_MMC_ENV_PART
  	if (CONFIG_SYS_MMC_ENV_PART != mmc->part_num) {
  		if (mmc_switch_part(CONFIG_SYS_MMC_ENV_DEV,
  				    CONFIG_SYS_MMC_ENV_PART)) {
  			puts("MMC partition switch failed
  ");
  			return -1;
  		}
  	}
  #endif

  	return 0;
  }

  static void fini_mmc_for_env(struct mmc *mmc)
  {
  #ifdef CONFIG_SYS_MMC_ENV_PART
  	if (CONFIG_SYS_MMC_ENV_PART != mmc->part_num)
  		mmc_switch_part(CONFIG_SYS_MMC_ENV_DEV,
  				mmc->part_num);
  #endif
  }

  #ifdef CONFIG_CMD_SAVEENV

  static inline int write_env(struct mmc *mmc, unsigned long size,
  			    unsigned long offset, const void *buffer)

  {
  	uint blk_start, blk_cnt, n;

  	blk_start	= ALIGN(offset, mmc->write_bl_len) / mmc->write_bl_len;
  	blk_cnt		= ALIGN(size, mmc->write_bl_len) / mmc->write_bl_len;

  
  	n = mmc->block_dev.block_write(CONFIG_SYS_MMC_ENV_DEV, blk_start,
  					blk_cnt, (u_char *)buffer);
  
  	return (n == blk_cnt) ? 0 : -1;
  }

  #ifdef CONFIG_ENV_OFFSET_REDUND
  static unsigned char env_flags;
  #endif

  int saveenv(void)
  {

  	ALLOC_CACHE_ALIGN_BUFFER(env_t, env_new, 1);

  	ssize_t	len;
  	char	*res;

  	struct mmc *mmc = find_mmc_device(CONFIG_SYS_MMC_ENV_DEV);

  	u32	offset;

  	int	ret, copy = 0;

  	if (init_mmc_for_env(mmc))

  		return 1;

  	res = (char *)&env_new->data;

  	len = hexport_r(&env_htab, '\0', 0, &res, ENV_SIZE, 0, NULL);

  	if (len < 0) {
  		error("Cannot export environment: errno = %d
  ", errno);

  		ret = 1;
  		goto fini;

  	}

  	env_new->crc = crc32(0, &env_new->data[0], ENV_SIZE);

  
  #ifdef CONFIG_ENV_OFFSET_REDUND
  	env_new->flags	= ++env_flags; /* increase the serial */
  
  	if (gd->env_valid == 1)
  		copy = 1;
  #endif
  
  	if (mmc_get_env_addr(mmc, copy, &offset)) {
  		ret = 1;
  		goto fini;
  	}
  
  	printf("Writing to %sMMC(%d)... ", copy ? "redundant " : "",
  	       CONFIG_SYS_MMC_ENV_DEV);

  	if (write_env(mmc, CONFIG_ENV_SIZE, offset, (u_char *)env_new)) {

  		puts("failed
  ");

  		ret = 1;
  		goto fini;

  	}
  
  	puts("done
  ");

  	ret = 0;

  #ifdef CONFIG_ENV_OFFSET_REDUND
  	gd->env_valid = gd->env_valid == 2 ? 1 : 2;
  #endif

  fini:
  	fini_mmc_for_env(mmc);
  	return ret;

  }
  #endif /* CONFIG_CMD_SAVEENV */

  static inline int read_env(struct mmc *mmc, unsigned long size,
  			   unsigned long offset, const void *buffer)

  {
  	uint blk_start, blk_cnt, n;

  	blk_start	= ALIGN(offset, mmc->read_bl_len) / mmc->read_bl_len;
  	blk_cnt		= ALIGN(size, mmc->read_bl_len) / mmc->read_bl_len;

  
  	n = mmc->block_dev.block_read(CONFIG_SYS_MMC_ENV_DEV, blk_start,
  					blk_cnt, (uchar *)buffer);
  
  	return (n == blk_cnt) ? 0 : -1;
  }

  #ifdef CONFIG_ENV_OFFSET_REDUND
  void env_relocate_spec(void)
  {
  #if !defined(ENV_IS_EMBEDDED)
  	struct mmc *mmc = find_mmc_device(CONFIG_SYS_MMC_ENV_DEV);
  	u32 offset1, offset2;
  	int read1_fail = 0, read2_fail = 0;
  	int crc1_ok = 0, crc2_ok = 0;

  	env_t *ep;

  	int ret;

  	ALLOC_CACHE_ALIGN_BUFFER(env_t, tmp_env1, 1);
  	ALLOC_CACHE_ALIGN_BUFFER(env_t, tmp_env2, 1);

  	if (tmp_env1 == NULL || tmp_env2 == NULL) {
  		puts("Can't allocate buffers for environment
  ");
  		ret = 1;
  		goto err;
  	}
  
  	if (init_mmc_for_env(mmc)) {
  		ret = 1;
  		goto err;
  	}
  
  	if (mmc_get_env_addr(mmc, 0, &offset1) ||
  	    mmc_get_env_addr(mmc, 1, &offset2)) {
  		ret = 1;
  		goto fini;
  	}
  
  	read1_fail = read_env(mmc, CONFIG_ENV_SIZE, offset1, tmp_env1);
  	read2_fail = read_env(mmc, CONFIG_ENV_SIZE, offset2, tmp_env2);
  
  	if (read1_fail && read2_fail)
  		puts("*** Error - No Valid Environment Area found
  ");
  	else if (read1_fail || read2_fail)
  		puts("*** Warning - some problems detected "
  		     "reading environment; recovered successfully
  ");
  
  	crc1_ok = !read1_fail &&
  		(crc32(0, tmp_env1->data, ENV_SIZE) == tmp_env1->crc);
  	crc2_ok = !read2_fail &&
  		(crc32(0, tmp_env2->data, ENV_SIZE) == tmp_env2->crc);
  
  	if (!crc1_ok && !crc2_ok) {
  		ret = 1;
  		goto fini;
  	} else if (crc1_ok && !crc2_ok) {
  		gd->env_valid = 1;
  	} else if (!crc1_ok && crc2_ok) {
  		gd->env_valid = 2;
  	} else {
  		/* both ok - check serial */
  		if (tmp_env1->flags == 255 && tmp_env2->flags == 0)
  			gd->env_valid = 2;
  		else if (tmp_env2->flags == 255 && tmp_env1->flags == 0)
  			gd->env_valid = 1;
  		else if (tmp_env1->flags > tmp_env2->flags)
  			gd->env_valid = 1;
  		else if (tmp_env2->flags > tmp_env1->flags)
  			gd->env_valid = 2;
  		else /* flags are equal - almost impossible */
  			gd->env_valid = 1;
  	}
  
  	free(env_ptr);
  
  	if (gd->env_valid == 1)
  		ep = tmp_env1;
  	else
  		ep = tmp_env2;
  
  	env_flags = ep->flags;
  	env_import((char *)ep, 0);
  	ret = 0;
  
  fini:
  	fini_mmc_for_env(mmc);
  err:
  	if (ret)
  		set_default_env(NULL);

  #endif
  }
  #else /* ! CONFIG_ENV_OFFSET_REDUND */

  void env_relocate_spec(void)
  {
  #if !defined(ENV_IS_EMBEDDED)

  	ALLOC_CACHE_ALIGN_BUFFER(char, buf, CONFIG_ENV_SIZE);

  	struct mmc *mmc = find_mmc_device(CONFIG_SYS_MMC_ENV_DEV);

  	u32 offset;

  	int ret;

  	if (init_mmc_for_env(mmc)) {
  		ret = 1;
  		goto err;
  	}

  	if (mmc_get_env_addr(mmc, 0, &offset)) {

  		ret = 1;
  		goto fini;
  	}

  	if (read_env(mmc, CONFIG_ENV_SIZE, offset, buf)) {

  		ret = 1;
  		goto fini;
  	}

  	env_import(buf, 1);

  	ret = 0;
  
  fini:
  	fini_mmc_for_env(mmc);
  err:
  	if (ret)
  		set_default_env(NULL);

  #endif
  }

  #endif /* CONFIG_ENV_OFFSET_REDUND */