/*
   * (C) Copyright 2001
   * Kyle Harris, Nexus Technologies, Inc. kharris@nexus-tech.net
   *
   * (C) Copyright 2001-2004
   * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   *

   * SPDX-License-Identifier:	GPL-2.0+

   */
  
  #include <common.h>
  #include <linux/byteorder/swab.h>

  flash_info_t flash_info[CONFIG_SYS_MAX_FLASH_BANKS];	/* info for FLASH chips    */

  
  /* Board support for 1 or 2 flash devices */
  #define FLASH_PORT_WIDTH32
  #undef FLASH_PORT_WIDTH16
  
  #ifdef FLASH_PORT_WIDTH16

  #define FLASH_PORT_WIDTH	ushort
  #define FLASH_PORT_WIDTHV	vu_short
  #define SWAP(x)			(x)

  #else

  #define FLASH_PORT_WIDTH	ulong
  #define FLASH_PORT_WIDTHV	vu_long
  #define SWAP(x)			(x)

  #endif
  
  /* Intel-compatible flash ID */

  #define INTEL_COMPAT		0x00890089
  #define INTEL_ALT		0x00B000B0

  
  /* Intel-compatible flash commands */

  #define INTEL_PROGRAM		0x00100010
  #define INTEL_ERASE		0x00200020
  #define INTEL_CLEAR		0x00500050
  #define INTEL_LOCKBIT		0x00600060
  #define INTEL_PROTECT		0x00010001
  #define INTEL_STATUS		0x00700070
  #define INTEL_READID		0x00900090
  #define INTEL_CONFIRM		0x00D000D0
  #define INTEL_RESET		0xFFFFFFFF

  
  /* Intel-compatible flash status bits */

  #define INTEL_FINISHED		0x00800080
  #define INTEL_OK		0x00800080

  #define FPW	FLASH_PORT_WIDTH
  #define FPWV	FLASH_PORT_WIDTHV

  
  #define mb() __asm__ __volatile__ ("" : : : "memory")
  
  /*-----------------------------------------------------------------------
   * Functions
   */
  static ulong flash_get_size (FPW *addr, flash_info_t *info);
  static int write_data (flash_info_t *info, ulong dest, FPW data);
  static void flash_get_offsets (ulong base, flash_info_t *info);
  void inline spin_wheel (void);

  static void flash_sync_real_protect (flash_info_t * info);
  static unsigned char intel_sector_protected (flash_info_t *info, ushort sector);

  
  /*-----------------------------------------------------------------------
   */
  
  unsigned long flash_init (void)
  {
  	int i;
  	ulong size = 0;

  	extern void flash_preinit(void);
  	extern void flash_afterinit(ulong, ulong);

  	ulong flashbase = CONFIG_SYS_FLASH_BASE;

  
  	flash_preinit();

  	for (i = 0; i < CONFIG_SYS_MAX_FLASH_BANKS; i++) {

  		switch (i) {
  		case 0:

  			memset(&flash_info[i], 0, sizeof(flash_info_t));
  			flash_get_size ((FPW *) flashbase, &flash_info[i]);
  			flash_get_offsets (flash_info[i].start[0], &flash_info[i]);

  			break;
  		default:
  			panic ("configured to many flash banks!
  ");
  			break;
  		}
  		size += flash_info[i].size;

  
  		/* get the h/w and s/w protection status in sync */
  		flash_sync_real_protect(&flash_info[i]);

  	}
  
  	/* Protect monitor and environment sectors
  	 */

  #if CONFIG_SYS_MONITOR_BASE >= CONFIG_SYS_FLASH_BASE

  #ifndef CONFIG_BOOT_ROM

  	flash_protect ( FLAG_PROTECT_SET,

  			CONFIG_SYS_MONITOR_BASE,
  			CONFIG_SYS_MONITOR_BASE + monitor_flash_len - 1,

  			&flash_info[0] );

  #endif
  #endif

  #ifdef	CONFIG_ENV_IS_IN_FLASH

  	flash_protect ( FLAG_PROTECT_SET,

  			CONFIG_ENV_ADDR,
  			CONFIG_ENV_ADDR + CONFIG_ENV_SIZE - 1, &flash_info[0] );

  #endif
  
  	flash_afterinit(flash_info[0].start[0], flash_info[0].size);

  
  	return size;
  }
  
  /*-----------------------------------------------------------------------
   */
  static void flash_get_offsets (ulong base, flash_info_t *info)
  {
  	int i;
  
  	if (info->flash_id == FLASH_UNKNOWN) {
  		return;
  	}
  
  	if ((info->flash_id & FLASH_VENDMASK) == FLASH_MAN_INTEL) {
  		for (i = 0; i < info->sector_count; i++) {
  			info->start[i] = base + (i * PHYS_FLASH_SECT_SIZE);

  		}
  	}
  }
  
  /*-----------------------------------------------------------------------
   */
  void flash_print_info (flash_info_t *info)
  {
  	int i;
  
  	if (info->flash_id == FLASH_UNKNOWN) {
  		printf ("missing or unknown FLASH type
  ");
  		return;
  	}
  
  	switch (info->flash_id & FLASH_VENDMASK) {
  	case FLASH_MAN_INTEL:
  		printf ("INTEL ");
  		break;
  	default:
  		printf ("Unknown Vendor ");
  		break;
  	}
  
  	switch (info->flash_id & FLASH_TYPEMASK) {

  	case FLASH_28F256J3A:
  		printf ("28F256J3A
  ");
  		break;

  	case FLASH_28F128J3A:
  		printf ("28F128J3A
  ");
  		break;
  
  	case FLASH_28F640J3A:
  		printf ("28F640J3A
  ");
  		break;
  
  	case FLASH_28F320J3A:
  		printf ("28F320J3A
  ");
  		break;
  
  	default:
  		printf ("Unknown Chip Type
  ");
  		break;
  	}
  
  	printf ("  Size: %ld MB in %d Sectors
  ",
  			info->size >> 20, info->sector_count);
  
  	printf ("  Sector Start Addresses:");
  	for (i = 0; i < info->sector_count; ++i) {
  		if ((i % 5) == 0)
  			printf ("
     ");
  		printf (" %08lX%s",
  			info->start[i],
  			info->protect[i] ? " (RO)" : "     ");
  	}
  	printf ("
  ");
  	return;
  }
  
  /*
   * The following code cannot be run from FLASH!
   */
  static ulong flash_get_size (FPW *addr, flash_info_t *info)
  {
  	volatile FPW value;
  
  	/* Write auto select command: read Manufacturer ID */
  	addr[0x5555] = (FPW) 0x00AA00AA;
  	addr[0x2AAA] = (FPW) 0x00550055;
  	addr[0x5555] = (FPW) 0x00900090;
  
  	mb ();

  	udelay(100);

  	value = addr[0];
  
  	switch (value) {
  
  	case (FPW) INTEL_MANUFACT:
  		info->flash_id = FLASH_MAN_INTEL;
  		break;
  
  	default:
  		info->flash_id = FLASH_UNKNOWN;
  		info->sector_count = 0;
  		info->size = 0;
  		addr[0] = (FPW) 0x00FF00FF;	/* restore read mode */
  		return (0);			/* no or unknown flash  */
  	}
  
  	mb ();
  	value = addr[1];			/* device ID        */
  
  	switch (value) {

  	case (FPW) INTEL_ID_28F256J3A:
  		info->flash_id += FLASH_28F256J3A;

  		/* In U-Boot we support only 32 MB (no bank-switching) */
  		info->sector_count = 256 / 2;
  		info->size =  0x04000000 / 2;

  		info->start[0] = CONFIG_SYS_FLASH_BASE + 0x02000000;

  		break;				/* => 32 MB     */

  	case (FPW) INTEL_ID_28F128J3A:
  		info->flash_id += FLASH_28F128J3A;
  		info->sector_count = 128;
  		info->size = 0x02000000;

  		info->start[0] = CONFIG_SYS_FLASH_BASE + 0x02000000;

  		break;				/* => 32 MB     */
  
  	case (FPW) INTEL_ID_28F640J3A:
  		info->flash_id += FLASH_28F640J3A;
  		info->sector_count = 64;
  		info->size = 0x01000000;

  		info->start[0] = CONFIG_SYS_FLASH_BASE + 0x03000000;

  		break;				/* => 16 MB     */
  
  	case (FPW) INTEL_ID_28F320J3A:
  		info->flash_id += FLASH_28F320J3A;
  		info->sector_count = 32;

  		info->size = 0x800000;

  		info->start[0] = CONFIG_SYS_FLASH_BASE + 0x03800000;

  		break;				/* => 8 MB     */
  
  	default:
  		info->flash_id = FLASH_UNKNOWN;
  		break;
  	}

  	if (info->sector_count > CONFIG_SYS_MAX_FLASH_SECT) {

  		printf ("** ERROR: sector count %d > max (%d) **
  ",

  			info->sector_count, CONFIG_SYS_MAX_FLASH_SECT);
  		info->sector_count = CONFIG_SYS_MAX_FLASH_SECT;

  	}
  
  	addr[0] = (FPW) 0x00FF00FF;		/* restore read mode */
  
  	return (info->size);
  }

  /*
   * This function gets the u-boot flash sector protection status
   * (flash_info_t.protect[]) in sync with the sector protection
   * status stored in hardware.
   */
  static void flash_sync_real_protect (flash_info_t * info)
  {
  	int i;
  
  	switch (info->flash_id & FLASH_TYPEMASK) {

  	case FLASH_28F256J3A:

  	case FLASH_28F128J3A:
  	case FLASH_28F640J3A:
  	case FLASH_28F320J3A:
  		for (i = 0; i < info->sector_count; ++i) {
  			info->protect[i] = intel_sector_protected(info, i);
  		}
  		break;
  	default:
  		/* no h/w protect support */
  		break;
  	}
  }
  
  
  /*
   * checks if "sector" in bank "info" is protected. Should work on intel
   * strata flash chips 28FxxxJ3x in 8-bit mode.
   * Returns 1 if sector is protected (or timed-out while trying to read
   * protection status), 0 if it is not.
   */
  static unsigned char intel_sector_protected (flash_info_t *info, ushort sector)
  {
  	FPWV *addr;
  	FPWV *lock_conf_addr;
  	ulong start;
  	unsigned char ret;
  
  	/*
  	 * first, wait for the WSM to be finished. The rationale for
  	 * waiting for the WSM to become idle for at most

  	 * CONFIG_SYS_FLASH_ERASE_TOUT is as follows. The WSM can be busy

  	 * because of: (1) erase, (2) program or (3) lock bit
  	 * configuration. So we just wait for the longest timeout of
  	 * the (1)-(3), i.e. the erase timeout.
  	 */
  
  	/* wait at least 35ns (W12) before issuing Read Status Register */
  	udelay(1);
  	addr = (FPWV *) info->start[sector];
  	*addr = (FPW) INTEL_STATUS;
  
  	start = get_timer (0);
  	while ((*addr & (FPW) INTEL_FINISHED) != (FPW) INTEL_FINISHED) {

  		if (get_timer (start) > CONFIG_SYS_FLASH_ERASE_TOUT) {

  			*addr = (FPW) INTEL_RESET; /* restore read mode */
  			printf("WSM busy too long, can't get prot status
  ");
  			return 1;
  		}
  	}

  	/* issue the Read Identifier Codes command */
  	*addr = (FPW) INTEL_READID;
  
  	/* wait at least 35ns (W12) before reading */
  	udelay(1);
  
  	/* Intel example code uses offset of 2 for 16 bit flash */
  	lock_conf_addr = (FPWV *) info->start[sector] + 2;
  	ret = (*lock_conf_addr & (FPW) INTEL_PROTECT) ? 1 : 0;
  
  	/* put flash back in read mode */
  	*addr = (FPW) INTEL_RESET;
  
  	return ret;
  }

  /*-----------------------------------------------------------------------
   */
  
  int flash_erase (flash_info_t *info, int s_first, int s_last)
  {
  	int flag, prot, sect;

  	ulong type, start;

  	int rcode = 0;
  
  	if ((s_first < 0) || (s_first > s_last)) {
  		if (info->flash_id == FLASH_UNKNOWN) {
  			printf ("- missing
  ");
  		} else {
  			printf ("- no sectors to erase
  ");
  		}
  		return 1;
  	}
  
  	type = (info->flash_id & FLASH_VENDMASK);
  	if ((type != FLASH_MAN_INTEL)) {
  		printf ("Can't erase unknown flash type %08lx - aborted
  ",
  			info->flash_id);
  		return 1;
  	}
  
  	prot = 0;
  	for (sect = s_first; sect <= s_last; ++sect) {
  		if (info->protect[sect]) {
  			prot++;
  		}
  	}
  
  	if (prot) {
  		printf ("- Warning: %d protected sectors will not be erased!
  ",
  			prot);
  	} else {
  		printf ("
  ");
  	}
  
  	start = get_timer (0);

  
  	/* Disable interrupts which might cause a timeout here */
  	flag = disable_interrupts ();
  
  	/* Start erase on unprotected sectors */
  	for (sect = s_first; sect <= s_last; sect++) {
  		if (info->protect[sect] == 0) {	/* not protected */
  			FPWV *addr = (FPWV *) (info->start[sect]);
  			FPW status;
  
  			printf ("Erasing sector %2d ... ", sect);
  
  			/* arm simple, non interrupt dependent timer */
  			start = get_timer(0);
  
  			*addr = (FPW) 0x00500050;	/* clear status register */
  			*addr = (FPW) 0x00200020;	/* erase setup */
  			*addr = (FPW) 0x00D000D0;	/* erase confirm */
  
  			while (((status = *addr) & (FPW) 0x00800080) != (FPW) 0x00800080) {

  				if (get_timer(start) > CONFIG_SYS_FLASH_ERASE_TOUT) {

  					printf ("Timeout
  ");
  					*addr = (FPW) 0x00B000B0;	/* suspend erase     */
  					*addr = (FPW) 0x00FF00FF;	/* reset to read mode */
  					rcode = 1;
  					break;
  				}
  			}
  
  			*addr = 0x00500050;	/* clear status register cmd.   */
  			*addr = 0x00FF00FF;	/* resest to read mode          */
  
  			printf (" done
  ");
  		}
  	}

  
  	if (flag)
  		enable_interrupts();

  	return rcode;
  }
  
  /*-----------------------------------------------------------------------
   * Copy memory to flash, returns:
   * 0 - OK
   * 1 - write timeout
   * 2 - Flash not erased
   * 4 - Flash not identified
   */
  
  int write_buff (flash_info_t *info, uchar *src, ulong addr, ulong cnt)
  {
  	ulong cp, wp;
  	FPW data;
  	int count, i, l, rc, port_width;
  
  	if (info->flash_id == FLASH_UNKNOWN) {
  		return 4;
  	}
  /* get lower word aligned address */
  #ifdef FLASH_PORT_WIDTH16
  	wp = (addr & ~1);
  	port_width = 2;
  #else
  	wp = (addr & ~3);
  	port_width = 4;
  #endif
  
  	/*
  	 * handle unaligned start bytes
  	 */
  	if ((l = addr - wp) != 0) {
  		data = 0;
  		for (i = 0, cp = wp; i < l; ++i, ++cp) {
  			data = (data << 8) | (*(uchar *) cp);
  		}
  		for (; i < port_width && cnt > 0; ++i) {
  			data = (data << 8) | *src++;
  			--cnt;
  			++cp;
  		}
  		for (; cnt == 0 && i < port_width; ++i, ++cp) {
  			data = (data << 8) | (*(uchar *) cp);
  		}
  
  		if ((rc = write_data (info, wp, SWAP (data))) != 0) {
  			return (rc);
  		}
  		wp += port_width;
  	}
  
  	/*
  	 * handle word aligned part
  	 */
  	count = 0;
  	while (cnt >= port_width) {
  		data = 0;
  		for (i = 0; i < port_width; ++i) {
  			data = (data << 8) | *src++;
  		}
  		if ((rc = write_data (info, wp, SWAP (data))) != 0) {
  			return (rc);
  		}
  		wp += port_width;
  		cnt -= port_width;
  		if (count++ > 0x800) {
  			spin_wheel ();
  			count = 0;
  		}
  	}
  
  	if (cnt == 0) {
  		return (0);
  	}
  
  	/*
  	 * handle unaligned tail bytes
  	 */
  	data = 0;
  	for (i = 0, cp = wp; i < port_width && cnt > 0; ++i, ++cp) {
  		data = (data << 8) | *src++;
  		--cnt;
  	}
  	for (; i < port_width; ++i, ++cp) {
  		data = (data << 8) | (*(uchar *) cp);
  	}
  
  	return (write_data (info, wp, SWAP (data)));
  }
  
  /*-----------------------------------------------------------------------
   * Write a word or halfword to Flash, returns:
   * 0 - OK
   * 1 - write timeout
   * 2 - Flash not erased
   */
  static int write_data (flash_info_t *info, ulong dest, FPW data)
  {
  	FPWV *addr = (FPWV *) dest;
  	ulong status;
  	ulong start;
  	int flag;

  	int rcode = 0;

  
  	/* Check if Flash is (sufficiently) erased */
  	if ((*addr & data) != data) {
  		printf ("not erased at %08lx (%lx)
  ", (ulong) addr, *addr);
  		return (2);
  	}
  	/* Disable interrupts which might cause a timeout here */
  	flag = disable_interrupts ();
  
  	*addr = (FPW) 0x00400040;	/* write setup */
  	*addr = data;
  
  	/* arm simple, non interrupt dependent timer */
  	start = get_timer(0);
  
  	/* wait while polling the status register */
  	while (((status = *addr) & (FPW) 0x00800080) != (FPW) 0x00800080) {

  		if (get_timer(start) > CONFIG_SYS_FLASH_WRITE_TOUT) {

  			rcode = 1;
  			break;

  		}
  	}
  
  	*addr = (FPW) 0x00FF00FF;	/* restore read mode */

  	if (flag)
  		enable_interrupts();
  
  	return rcode;

  }
  
  void inline spin_wheel (void)
  {
  	static int p = 0;
  	static char w[] = "\\/-";
  
  	printf ("\010%c", w[p]);
  	(++p == 3) ? (p = 0) : 0;
  }
  
  /*-----------------------------------------------------------------------
   * Set/Clear sector's lock bit, returns:
   * 0 - OK
   * 1 - Error (timeout, voltage problems, etc.)
   */

  int flash_real_protect (flash_info_t *info, long sector, int prot)

  {
  	ulong start;
  	int i;
  	int rc = 0;
  	vu_long *addr = (vu_long *)(info->start[sector]);
  	int flag = disable_interrupts();
  
  	*addr = INTEL_CLEAR;	/* Clear status register */
  	if (prot) {			/* Set sector lock bit */
  		*addr = INTEL_LOCKBIT;	/* Sector lock bit */
  		*addr = INTEL_PROTECT;	/* set */
  	}
  	else {				/* Clear sector lock bit */
  		*addr = INTEL_LOCKBIT;	/* All sectors lock bits */
  		*addr = INTEL_CONFIRM;	/* clear */
  	}
  
  	start = get_timer(0);
  
  	while ((*addr & INTEL_FINISHED) != INTEL_FINISHED) {

  		if (get_timer(start) > CONFIG_SYS_FLASH_UNLOCK_TOUT) {

  			printf("Flash lock bit operation timed out
  ");
  			rc = 1;
  			break;
  		}
  	}
  
  	if (*addr != INTEL_OK) {
  		printf("Flash lock bit operation failed at %08X, CSR=%08X
  ",
  		       (uint)addr, (uint)*addr);
  		rc = 1;
  	}
  
  	if (!rc)
  		info->protect[sector] = prot;
  
  	/*
  	 * Clear lock bit command clears all sectors lock bits, so
  	 * we have to restore lock bits of protected sectors.

  	 * WARNING: code below re-locks sectors only for one bank (info).
  	 * This causes problems on boards where several banks share
  	 * the same chip, as sectors in othere banks will be unlocked
  	 * but not re-locked. It works fine on pm520 though, as there
  	 * is only one chip and one bank.

  	 */
  	if (!prot)
  	{
  		for (i = 0; i < info->sector_count; i++)
  		{
  			if (info->protect[i])
  			{
  				start = get_timer(0);
  				addr = (vu_long *)(info->start[i]);
  				*addr = INTEL_LOCKBIT;	/* Sector lock bit */
  				*addr = INTEL_PROTECT;	/* set */
  				while ((*addr & INTEL_FINISHED) != INTEL_FINISHED)
  				{

  					if (get_timer(start) > CONFIG_SYS_FLASH_UNLOCK_TOUT)

  					{
  						printf("Flash lock bit operation timed out
  ");
  						rc = 1;
  						break;
  					}
  				}
  			}
  		}

  		/*
  		 * get the s/w sector protection status in sync with the h/w,
  		 * in case something went wrong during the re-locking.
  		 */
  		flash_sync_real_protect(info); /* resets flash to read  mode */

  	}
  
  	if (flag)
  		enable_interrupts();
  
  	*addr = INTEL_RESET;		/* Reset to read array mode */
  
  	return rc;
  }