/*
   * (C) Copyright 2000, 2001
   * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   *

   * SPDX-License-Identifier:	GPL-2.0+

   */

  /*
   * Support for read and write access to EEPROM like memory devices. This
   * includes regular EEPROM as well as  FRAM (ferroelectic nonvolaile RAM).
   * FRAM devices read and write data at bus speed. In particular, there is no

   * write delay. Also, there is no limit imposed on the number of bytes that can

   * be transferred with a single read or write.

   *

   * Use the following configuration options to ensure no unneeded performance
   * degradation (typical for EEPROM) is incured for FRAM memory:

   *

   * #define CONFIG_SYS_I2C_FRAM
   * #undef CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS

   *
   */

  #include <common.h>
  #include <config.h>
  #include <command.h>
  #include <i2c.h>

  #include <eeprom_layout.h>

  #ifndef	CONFIG_SYS_I2C_SPEED
  #define	CONFIG_SYS_I2C_SPEED	50000

  #endif

  #ifndef CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS
  #define CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS	0
  #endif

  #ifndef CONFIG_SYS_EEPROM_PAGE_WRITE_BITS
  #define CONFIG_SYS_EEPROM_PAGE_WRITE_BITS	8
  #endif

  #ifndef	I2C_RXTX_LEN
  #define I2C_RXTX_LEN	128
  #endif

  #define	EEPROM_PAGE_SIZE	(1 << CONFIG_SYS_EEPROM_PAGE_WRITE_BITS)
  #define	EEPROM_PAGE_OFFSET(x)	((x) & (EEPROM_PAGE_SIZE - 1))

  /*

   * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 2 (16-bit EEPROM address) offset is

   *   0x000nxxxx for EEPROM address selectors at n, offset xxxx in EEPROM.
   *

   * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1 (8-bit EEPROM page address) offset is

   *   0x00000nxx for EEPROM address selectors and page number at n.
   */

  #if !defined(CONFIG_SPI) || defined(CONFIG_ENV_EEPROM_IS_ON_I2C)

  #if !defined(CONFIG_SYS_I2C_EEPROM_ADDR_LEN) || \

  	(CONFIG_SYS_I2C_EEPROM_ADDR_LEN < 1) || \
  	(CONFIG_SYS_I2C_EEPROM_ADDR_LEN > 2)

  #error CONFIG_SYS_I2C_EEPROM_ADDR_LEN must be 1 or 2

  #endif
  #endif

  __weak int eeprom_write_enable(unsigned dev_addr, int state)
  {
  	return 0;
  }

  void eeprom_init(int bus)

  {
  	/* SPI EEPROM */
  #if defined(CONFIG_SPI) && !defined(CONFIG_ENV_EEPROM_IS_ON_I2C)

  	spi_init_f();

  #endif
  
  	/* I2C EEPROM */

  #if defined(CONFIG_HARD_I2C) || defined(CONFIG_SYS_I2C)

  #if defined(CONFIG_SYS_I2C)
  	if (bus >= 0)
  		i2c_set_bus_num(bus);
  #endif

  	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
  #endif
  }

  static int eeprom_addr(unsigned dev_addr, unsigned offset, uchar *addr)
  {
  	unsigned blk_off;
  	int alen;
  
  	blk_off = offset & 0xff;	/* block offset */
  #if CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1
  	addr[0] = offset >> 8;		/* block number */
  	addr[1] = blk_off;		/* block offset */
  	alen = 2;
  #else
  	addr[0] = offset >> 16;		/* block number */
  	addr[1] = offset >>  8;		/* upper address octet */
  	addr[2] = blk_off;		/* lower address octet */
  	alen = 3;
  #endif	/* CONFIG_SYS_I2C_EEPROM_ADDR_LEN */
  
  	addr[0] |= dev_addr;		/* insert device address */
  
  	return alen;
  }

  static int eeprom_len(unsigned offset, unsigned end)
  {
  	unsigned len = end - offset;
  
  	/*
  	 * For a FRAM device there is no limit on the number of the
  	 * bytes that can be ccessed with the single read or write
  	 * operation.
  	 */
  #if !defined(CONFIG_SYS_I2C_FRAM)
  	unsigned blk_off = offset & 0xff;
  	unsigned maxlen = EEPROM_PAGE_SIZE - EEPROM_PAGE_OFFSET(blk_off);
  
  	if (maxlen > I2C_RXTX_LEN)
  		maxlen = I2C_RXTX_LEN;
  
  	if (len > maxlen)
  		len = maxlen;
  #endif
  
  	return len;
  }

  static int eeprom_rw_block(unsigned offset, uchar *addr, unsigned alen,
  			   uchar *buffer, unsigned len, bool read)
  {
  	int ret = 0;
  
  	/* SPI */
  #if defined(CONFIG_SPI) && !defined(CONFIG_ENV_EEPROM_IS_ON_I2C)
  	if (read)
  		spi_read(addr, alen, buffer, len);
  	else
  		spi_write(addr, alen, buffer, len);
  #else	/* I2C */
  
  #if defined(CONFIG_SYS_I2C_EEPROM_BUS)
  	i2c_set_bus_num(CONFIG_SYS_I2C_EEPROM_BUS);
  #endif
  
  	if (read)
  		ret = i2c_read(addr[0], offset, alen - 1, buffer, len);
  	else
  		ret = i2c_write(addr[0], offset, alen - 1, buffer, len);
  
  	if (ret)
  		ret = 1;
  #endif
  	return ret;
  }

  static int eeprom_rw(unsigned dev_addr, unsigned offset, uchar *buffer,
  		     unsigned cnt, bool read)

  {
  	unsigned end = offset + cnt;

  	unsigned alen, len;

  	int rcode = 0;

  	uchar addr[3];

  	while (offset < end) {

  		alen = eeprom_addr(dev_addr, offset, addr);

  		len = eeprom_len(offset, end);

  		rcode = eeprom_rw_block(offset, addr, alen, buffer, len, read);

  		buffer += len;
  		offset += len;

  
  		if (!read)
  			udelay(CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS * 1000);

  	}

  	return rcode;
  }

  int eeprom_read(unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt)

  {

  	/*
  	 * Read data until done or would cross a page boundary.
  	 * We must write the address again when changing pages
  	 * because the next page may be in a different device.
  	 */
  	return eeprom_rw(dev_addr, offset, buffer, cnt, 1);
  }

  int eeprom_write(unsigned dev_addr, unsigned offset,
  		 uchar *buffer, unsigned cnt)

  {
  	int ret;

  	eeprom_write_enable(dev_addr, 1);

  	/*
  	 * Write data until done or would cross a write page boundary.

  	 * We must write the address again when changing pages
  	 * because the address counter only increments within a page.
  	 */

  	ret = eeprom_rw(dev_addr, offset, buffer, cnt, 0);

  
  	eeprom_write_enable(dev_addr, 0);

  	return ret;

  }

  static int parse_numeric_param(char *str)
  {
  	char *endptr;
  	int value = simple_strtol(str, &endptr, 16);
  
  	return (*endptr != '\0') ? -1 : value;
  }
  
  /**
   * parse_i2c_bus_addr - parse the i2c bus and i2c devaddr parameters
   *
   * @i2c_bus:	address to store the i2c bus
   * @i2c_addr:	address to store the device i2c address
   * @argc:	count of command line arguments left to parse
   * @argv:	command line arguments left to parse
   * @argc_no_bus_addr:	argc value we expect to see when bus & addr aren't given
   *
   * @returns:	number of arguments parsed or CMD_RET_USAGE if error
   */
  static int parse_i2c_bus_addr(int *i2c_bus, ulong *i2c_addr, int argc,
  			      char * const argv[], int argc_no_bus_addr)
  {
  	int argc_no_bus = argc_no_bus_addr + 1;
  	int argc_bus_addr = argc_no_bus_addr + 2;
  
  #ifdef CONFIG_SYS_DEF_EEPROM_ADDR
  	if (argc == argc_no_bus_addr) {
  		*i2c_bus = -1;
  		*i2c_addr = CONFIG_SYS_DEF_EEPROM_ADDR;
  
  		return 0;
  	}
  #endif
  	if (argc == argc_no_bus) {
  		*i2c_bus = -1;
  		*i2c_addr = parse_numeric_param(argv[0]);
  
  		return 1;
  	}
  
  	if (argc == argc_bus_addr) {
  		*i2c_bus = parse_numeric_param(argv[0]);
  		*i2c_addr = parse_numeric_param(argv[1]);
  
  		return 2;
  	}
  
  	return CMD_RET_USAGE;
  }

  #ifdef CONFIG_CMD_EEPROM_LAYOUT

  
  __weak int eeprom_parse_layout_version(char *str)
  {
  	return LAYOUT_VERSION_UNRECOGNIZED;
  }
  
  static unsigned char eeprom_buf[CONFIG_SYS_EEPROM_SIZE];
  
  #ifndef CONFIG_EEPROM_LAYOUT_HELP_STRING
  #define CONFIG_EEPROM_LAYOUT_HELP_STRING "<not defined>"
  #endif

  #endif

  enum eeprom_action {

  	EEPROM_READ,
  	EEPROM_WRITE,

  	EEPROM_PRINT,
  	EEPROM_UPDATE,
  	EEPROM_ACTION_INVALID,
  };
  
  static enum eeprom_action parse_action(char *cmd)
  {

  	if (!strncmp(cmd, "read", 4))
  		return EEPROM_READ;
  	if (!strncmp(cmd, "write", 5))
  		return EEPROM_WRITE;
  #ifdef CONFIG_CMD_EEPROM_LAYOUT

  	if (!strncmp(cmd, "print", 5))
  		return EEPROM_PRINT;
  	if (!strncmp(cmd, "update", 6))
  		return EEPROM_UPDATE;

  #endif

  
  	return EEPROM_ACTION_INVALID;
  }

  static int eeprom_execute_command(enum eeprom_action action, int i2c_bus,

  				  ulong i2c_addr, int layout_ver, char *key,
  				  char *value, ulong addr, ulong off, ulong cnt)

  {

  	int rcode = 0;
  	const char *const fmt =
  		"
  EEPROM @0x%lX %s: addr %08lx  off %04lx  count %ld ... ";
  #ifdef CONFIG_CMD_EEPROM_LAYOUT

  	struct eeprom_layout layout;

  #endif

  
  	if (action == EEPROM_ACTION_INVALID)
  		return CMD_RET_USAGE;
  
  	eeprom_init(i2c_bus);

  	if (action == EEPROM_READ) {
  		printf(fmt, i2c_addr, "read", addr, off, cnt);
  
  		rcode = eeprom_read(i2c_addr, off, (uchar *)addr, cnt);
  
  		puts("done
  ");
  		return rcode;
  	} else if (action == EEPROM_WRITE) {
  		printf(fmt, i2c_addr, "write", addr, off, cnt);
  
  		rcode = eeprom_write(i2c_addr, off, (uchar *)addr, cnt);
  
  		puts("done
  ");
  		return rcode;
  	}
  
  #ifdef CONFIG_CMD_EEPROM_LAYOUT

  	rcode = eeprom_read(i2c_addr, 0, eeprom_buf, CONFIG_SYS_EEPROM_SIZE);
  	if (rcode < 0)
  		return rcode;
  
  	eeprom_layout_setup(&layout, eeprom_buf, CONFIG_SYS_EEPROM_SIZE,
  			    layout_ver);
  
  	if (action == EEPROM_PRINT) {
  		layout.print(&layout);
  		return 0;
  	}
  
  	layout.update(&layout, key, value);
  
  	rcode = eeprom_write(i2c_addr, 0, layout.data, CONFIG_SYS_EEPROM_SIZE);

  #endif

  
  	return rcode;
  }
  
  #define NEXT_PARAM(argc, index)	{ (argc)--; (index)++; }

  int do_eeprom(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])

  {
  	int layout_ver = LAYOUT_VERSION_AUTODETECT;
  	enum eeprom_action action = EEPROM_ACTION_INVALID;

  	int i2c_bus = -1, index = 0;
  	ulong i2c_addr = -1, addr = 0, cnt = 0, off = 0;
  	int ret;

  	char *field_name = "";
  	char *field_value = "";
  
  	if (argc <= 1)
  		return CMD_RET_USAGE;
  
  	NEXT_PARAM(argc, index); /* Skip program name */
  
  	action = parse_action(argv[index]);
  	NEXT_PARAM(argc, index);

  	if (action == EEPROM_ACTION_INVALID)

  		return CMD_RET_USAGE;

  #ifdef CONFIG_CMD_EEPROM_LAYOUT
  	if (action == EEPROM_PRINT || action == EEPROM_UPDATE) {
  		if (!strcmp(argv[index], "-l")) {
  			NEXT_PARAM(argc, index);
  			layout_ver = eeprom_parse_layout_version(argv[index]);
  			NEXT_PARAM(argc, index);
  		}

  	}

  #endif

  	switch (action) {
  	case EEPROM_READ:
  	case EEPROM_WRITE:
  		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
  					 argv + index, 3);
  		break;
  	case EEPROM_PRINT:
  		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
  					 argv + index, 0);
  		break;
  	case EEPROM_UPDATE:
  		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
  					 argv + index, 2);
  		break;
  	default:
  		/* Get compiler to stop whining */

  		return CMD_RET_USAGE;

  	}

  	if (ret == CMD_RET_USAGE)
  		return ret;

  	while (ret--)

  		NEXT_PARAM(argc, index);

  	if (action == EEPROM_READ || action == EEPROM_WRITE) {
  		addr = parse_numeric_param(argv[index]);
  		NEXT_PARAM(argc, index);
  		off = parse_numeric_param(argv[index]);

  		NEXT_PARAM(argc, index);

  		cnt = parse_numeric_param(argv[index]);

  	}

  #ifdef CONFIG_CMD_EEPROM_LAYOUT

  	if (action == EEPROM_UPDATE) {
  		field_name = argv[index];
  		NEXT_PARAM(argc, index);
  		field_value = argv[index];
  		NEXT_PARAM(argc, index);

  	}
  #endif

  	return eeprom_execute_command(action, i2c_bus, i2c_addr, layout_ver,
  				      field_name, field_value, addr, off, cnt);

  }

  U_BOOT_CMD(

  	eeprom,	8,	1,	do_eeprom,

  	"EEPROM sub-system",

  	"read  <bus> <devaddr> addr off cnt
  "
  	"eeprom write <bus> <devaddr> addr off cnt
  "

  	"       - read/write `cnt' bytes from `devaddr` EEPROM at offset `off'"

  #ifdef CONFIG_CMD_EEPROM_LAYOUT
  	"
  "

  	"eeprom print [-l <layout_version>] <bus> <devaddr>
  "

  	"       - Print layout fields and their data in human readable format
  "

  	"eeprom update [-l <layout_version>] <bus> <devaddr> field_name field_value
  "

  	"       - Update a specific eeprom field with new data.
  "
  	"         The new data must be written in the same human readable format as shown by the print command.
  "
  	"
  "
  	"LAYOUT VERSIONS
  "
  	"The -l option can be used to force the command to interpret the EEPROM data using the chosen layout.
  "
  	"If the -l option is omitted, the command will auto detect the layout based on the data in the EEPROM.
  "
  	"The values which can be provided with the -l option are:
  "
  	CONFIG_EEPROM_LAYOUT_HELP_STRING"
  "
  #endif

  )