/*
 * flashutl.c - Flash Read/write/Erase routines
 *
 * Copyright 2007, Broadcom Corporation
 * All Rights Reserved.
 * 
 * THIS SOFTWARE IS OFFERED "AS IS", AND BROADCOM GRANTS NO WARRANTIES OF ANY
 * KIND, EXPRESS OR IMPLIED, BY STATUTE, COMMUNICATION OR OTHERWISE. BROADCOM
 * SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A SPECIFIC PURPOSE OR NONINFRINGEMENT CONCERNING THIS SOFTWARE.
 *
 * $Id$
 */

#include <typedefs.h>
#include <osl.h>

#define DECLARE_FLASHES
#include <bcmutils.h>
#include <sbutils.h>
#include <sbconfig.h>
#include <flash.h>
#include <sflash.h>
#include <flashutl.h>
#include <bcmnvram.h>

#define DPRINT(x)

#define ERR2	0x30		/* Mask for err UNUSED */
#define DONE	0x80		/* Mask for done */
#define WBUFSIZE 32		/* Write Buffer size */
#define FLASH_TRIES 4000000	/* retry count */
#define CMD_ADDR ((unsigned long)0xFFFFFFFF)

/* 'which' param for block() */
#define BLOCK_BASE	0	/* Base of block */
#define BLOCK_LIM	1	/* Limit of block */

#define FLASH_ADDR(off) ((unsigned long)flashutl_base + (off))

/* Local vars */
static sb_t *sbh = NULL;
static chipcregs_t *cc = NULL;

/* Global vars */
uint8 *flashutl_base = NULL;
flash_desc_t *flashutl_desc = NULL;
flash_cmds_t *flashutl_cmd = NULL;
uint8 flashutl_wsz = sizeof (uint16);

static void scmd (uint16 cmd, unsigned long off);
static void cmd (uint16 cmd, unsigned long off);
static void flash_reset (void);
static int flash_poll (unsigned long off, uint16 data);
static unsigned long block (unsigned long addr, int which);
static int flash_eraseblk (unsigned long off);
static int flash_write (unsigned long off, uint8 * src, uint nbytes);
static uint16 INLINE flash_readword (unsigned long addr);
static void INLINE flash_writeword (unsigned long addr, uint16 data);

int sysFlashErase (uint off, unsigned int numbytes);

/* Read the flash ID and set the globals */
int
sysFlashInit (char *flash_str)
{
  osl_t *osh;
  uint32 fltype = PFLASH;
  uint16 flash_vendid = 0;
  uint16 flash_devid = 0;
  int idx;
  struct sflash *sflash;

  /*
   * Check for serial flash.
   */
  sbh = sb_kattach (SB_OSH);
  ASSERT (sbh);

  osh = sb_osh (sbh);

  flashutl_base = (uint8 *) OSL_UNCACHED (SB_FLASH1);
  flashutl_wsz = sizeof (uint16);
  cc = (chipcregs_t *) sb_setcore (sbh, SB_CC, 0);
  if (cc)
    {
      flashutl_base = (uint8 *) OSL_UNCACHED (SB_FLASH2);
      flashutl_wsz = (R_REG (osh, &cc->flash_config) & CC_CFG_DS) ?
	sizeof (uint16) : sizeof (uint8);
      /* Select SFLASH ? */
      fltype = R_REG (osh, &cc->capabilities) & CC_CAP_FLASH_MASK;
      if (fltype == SFLASH_ST || fltype == SFLASH_AT)
	{
	  sflash = sflash_init (sbh, cc);
	  flashutl_cmd = &sflash_cmd_t;
	  flashutl_desc = &sflash_desc;
	  flashutl_desc->size = sflash->size;
	  if (flash_str)
	    sprintf (flash_str, "SFLASH %d kB", sflash->size / 1024);
	  return (0);
	}
    }

  ASSERT (flashutl_wsz == sizeof (uint8) || flashutl_wsz == sizeof (uint16));

  /*
   * Parallel flash support
   *  Some flashes have different unlock addresses, try each it turn
   */
  for (idx = 0; fltype == PFLASH && idx < ARRAYSIZE (flash_cmds); idx++)
    {
      flashutl_cmd = &flash_cmds[idx];
      if (flashutl_cmd->type == OLD)
	continue;

      if (flashutl_cmd->read_id)
	cmd (flashutl_cmd->read_id, CMD_ADDR);

#ifdef MIPSEB
      flash_vendid = flash_readword (FLASH_ADDR (2));
      flash_devid = flash_readword (FLASH_ADDR (0));
#else
      flash_vendid = flash_readword (FLASH_ADDR (0));
      flash_devid = flash_readword (FLASH_ADDR (2));
#endif /* MIPSEB */

      /* Funky AMD, uses 3 byte device ID so use first byte (4th addr) to
       * identify it is a 3-byte ID and use the next two bytes (5th & 6th addr)
       * to form a word for unique identification of format xxyy, where
       * xx = 5th addr and yy = 6th addr
       */
      if ((flash_vendid == 1) && (flash_devid == 0x227e))
	{
	  /* Get real devid */
	  uint16 flash_devid_5th;
#ifdef MIPSEB
	  flash_devid_5th = flash_readword (FLASH_ADDR (0x1e)) << 8;
	  flash_devid =
	    (flash_readword (FLASH_ADDR (0x1c)) & 0xff) | flash_devid_5th;
#else
	  flash_devid_5th = flash_readword (FLASH_ADDR (0x1c)) << 8;
	  flash_devid =
	    (flash_readword (FLASH_ADDR (0x1e)) & 0xff) | flash_devid_5th;
#endif /* MIPSEB */
	}

      flashutl_desc = flashes;
      while (flashutl_desc->mfgid != 0 &&
	     !(flashutl_desc->mfgid == flash_vendid &&
	       flashutl_desc->devid == flash_devid))
	{
	  flashutl_desc++;
	}
      if (flashutl_desc->mfgid != 0)
	break;
    }

  if (flashutl_desc->mfgid == 0)
    {
      flashutl_desc = NULL;
      flashutl_cmd = NULL;
    }
  else
    {
      flashutl_cmd = flash_cmds;
      while (flashutl_cmd->type != 0
	     && flashutl_cmd->type != flashutl_desc->type)
	flashutl_cmd++;
      if (flashutl_cmd->type == 0)
	flashutl_cmd = NULL;
    }

  if (flashutl_cmd != NULL)
    {
      flash_reset ();
    }

  if (flashutl_desc == NULL)
    {
      if (flash_str)
	sprintf (flash_str, "UNKNOWN 0x%x 0x%x", flash_vendid, flash_devid);
      DPRINT (("Flash type UNKNOWN\n"));
      return 1;
    }

  if (flash_str)
    strcpy (flash_str, flashutl_desc->desc);
  DPRINT (("Flash type \"%s\"\n", flashutl_desc->desc));

  return 0;
}

static int
flash_eraseblk (unsigned long addr)
{
  unsigned long a;
  uint16 st;

  a = (unsigned long) addr;
  if (a >= flashutl_desc->size)
    return 1;

  a = block (a, BLOCK_BASE);

  /* Ensure blocks are unlocked (for intel chips) */
  if (flashutl_cmd->type == BSC)
    {
      scmd ((unsigned char) INTEL_UNLOCK1, a);
      scmd ((unsigned char) INTEL_UNLOCK2, a);
    }

  if (flashutl_cmd->pre_erase)
    cmd (flashutl_cmd->pre_erase, CMD_ADDR);
  if (flashutl_cmd->erase_block)
    cmd (flashutl_cmd->erase_block, a);
  if (flashutl_cmd->confirm)
    scmd (flashutl_cmd->confirm, a);

  if (flashutl_wsz == sizeof (uint8))
    st = flash_poll (a, 0xff);
  else
    st = flash_poll (a, 0xffff);

  flash_reset ();

  if (st)
    {
      DPRINT (("Erase of block 0x%08lx-0x%08lx failed\n",
	       a, block ((unsigned long) addr, BLOCK_LIM)));
      return st;
    }

  DPRINT (("Erase of block 0x%08lx-0x%08lx done\n", a,
	   block ((unsigned long) addr, BLOCK_LIM)));

  return 0;
}

static int
flash_write (unsigned long off, uint8 * src, uint nbytes)
{
  uint8 *dest;
  uint16 st, data;
  uint i, len;

  ASSERT (flashutl_desc != NULL);

  if (off >= flashutl_desc->size)
    return 1;

  ASSERT (!(off & (flashutl_wsz - 1)));

  dest = (uint8 *) FLASH_ADDR (off);
  st = 0;

  while (nbytes)
    {
      if ((flashutl_desc->type == SCS) &&
	  flashutl_cmd->write_buf && ((off & (WBUFSIZE - 1)) == 0))
	{
	  /* issue write command */
	  if (flashutl_cmd->write_buf)
	    cmd (flashutl_cmd->write_buf, off);
	  if ((st = flash_poll (off, DONE)))
	    continue;

	  len = MIN (nbytes, WBUFSIZE);

#ifndef MIPSEB
	  /* write (length - 1) */
	  cmd (len / sizeof (uint16) - 1, off);

	  /* write data */
	  for (i = 0; i < len; i += sizeof (uint16),
	       dest += sizeof (uint16), src += sizeof (uint16))
	    *(uint16 *) dest = *(uint16 *) src;
#else
	  /*
	   * BCM4710 endianness is word consistent but
	   * byte/short scrambled. This write buffer
	   * mechanism appears to be sensitive to the
	   * order of the addresses hence we need to
	   * unscramble them. We may also need to pad
	   * the source with two bytes of 0xffff in case
	   * an odd number of shorts are presented.
	   */

	  /* write (padded length - 1) */
	  cmd ((ROUNDUP (len, sizeof (uint32)) / sizeof (uint16)) - 1, off);

	  /* write data (plus pad if necessary) */
	  for (i = 0; i < ROUNDUP (len, sizeof (uint32));
	       i += sizeof (uint32), dest += sizeof (uint32), src +=
	       sizeof (uint32))
	    {
	      *((uint16 *) dest + 1) = ((i + sizeof (uint16)) < len) ?
		*((uint16 *) src + 1) : 0xffff;
	      *(uint16 *) dest = *(uint16 *) src;
	    }
#endif /* MIPSEB */

	  /* write confirm */
	  if (flashutl_cmd->confirm)
	    cmd (flashutl_cmd->confirm, off);

	  if ((st = flash_poll (off, DONE)))
	    break;
	}
      else
	{
	  /* issue write command */
	  if (flashutl_cmd->write_word)
	    cmd (flashutl_cmd->write_word, CMD_ADDR);

	  /* write data */
	  data = flash_readword ((unsigned long) src);
	  flash_writeword ((unsigned long) dest, data);

	  /* poll for done */
	  if ((st = flash_poll (off, data)))
	    break;

	  len = MIN (nbytes, flashutl_wsz);
	  dest += len;
	  src += len;
	}

      nbytes -= len;
      off += len;
    }

  flash_reset ();

  return st;
}

static uint16 INLINE
flash_readword (unsigned long addr)
{
  if (flashutl_wsz == sizeof (uint8))
    return *(uint8 *) addr;
  else
    return *(uint16 *) addr;
}

static void INLINE
flash_writeword (unsigned long addr, uint16 data)
{
  if (flashutl_wsz == sizeof (uint8))
    *(uint8 *) addr = (uint8) data;
  else
    *(uint16 *) addr = data;
}

/* Writes a single command to the flash. */
static void
scmd (uint16 cmd, unsigned long off)
{
  /*  cmd |= cmd << 8; */

  flash_writeword (FLASH_ADDR (off), cmd);
}

/* Writes a command to flash, performing an unlock if needed. */
static void
cmd (uint16 cmd, unsigned long off)
{
  int i;
  unlock_cmd_t *ul = NULL;

  ASSERT (flashutl_cmd != NULL);

  switch (flashutl_cmd->type)
    {
    case AMD:
      ul = &unlock_cmd_amd;
      break;
    case SST:
      ul = &unlock_cmd_sst;
      break;
    default:
      break;
    }

  if (flashutl_cmd->need_unlock)
    {
      ASSERT (ul);
      for (i = 0; i < UNLOCK_CMD_WORDS; i++)
	flash_writeword (FLASH_ADDR (ul->addr[i]), ul->cmd[i]);
    }

  /* cmd |= cmd << 8; */

  if (off == CMD_ADDR)
    {
      switch (flashutl_cmd->type)
	{
	case AMD:
	  off = AMD_CMD;
	  break;
	case SST:
	  off = SST_CMD;
	  break;
	default:
	  off = 0;
	  break;
	}
    }

#ifdef MIPSEB
  off ^= 2;
#endif /* MIPSEB */

  flash_writeword (FLASH_ADDR (off), cmd);
}

static void
flash_reset ()
{
  ASSERT (flashutl_desc != NULL);

  if (flashutl_cmd->clear_csr)
    scmd (flashutl_cmd->clear_csr, 0);
  if (flashutl_cmd->read_array)
    scmd (flashutl_cmd->read_array, 0);
}

static int
flash_poll (unsigned long off, uint16 data)
{
  unsigned long addr;
  int cnt = FLASH_TRIES;
  uint16 st;

  ASSERT (flashutl_desc != NULL);

  if (flashutl_desc->type == AMD || flashutl_desc->type == SST)
    {
      /* AMD style poll checkes the address being written */
      addr = FLASH_ADDR (off);
      while ((st = flash_readword (addr)) != data && cnt != 0)
	cnt--;
      if (cnt == 0)
	{
	  DPRINT (("flash_poll: timeout, off %lx, read 0x%x, expected 0x%x\n",
		   off, st, data));
	  return -1;
	}
    }
  else
    {
      /* INTEL style poll is at second word of the block being written */
      addr = FLASH_ADDR (block (off, BLOCK_BASE) + sizeof (uint16));
      while (((st = flash_readword (addr)) & DONE) == 0 && cnt != 0)
	cnt--;
      if (cnt == 0)
	{
	  DPRINT (("flash_poll: timeout, error status = 0x%x\n", st));
	  return -1;
	}
    }

  return 0;
}

static unsigned long
block (unsigned long addr, int which)
{
  unsigned long b, l, sb;
  uint *sblocks;
  int i;

  ASSERT (flashutl_desc != NULL);

  ASSERT (addr < (unsigned long) flashutl_desc->size);

  b = addr / flashutl_desc->bsize;
  /* check for an address a full size block */
  if (b >= flashutl_desc->ff && b <= flashutl_desc->lf)
    {
      if (which == BLOCK_LIM)
	b++;
      return (b * flashutl_desc->bsize);
    }

  /* search for the sub-block */
  if (flashutl_desc->ff == 0)
    {
      /* sub blocks are at the end of the flash */
      sb = flashutl_desc->bsize * (flashutl_desc->lf + 1);
    }
  else
    {
      /* sub blocks are at the start of the flash */
      sb = 0;
    }

  sblocks = flashutl_desc->subblocks;
  for (i = 0; i < flashutl_desc->nsub; i++)
    {
      b = sb + sblocks[i];
      l = sb + sblocks[i + 1];
      if (addr >= b && addr < l)
	{
	  if (which == BLOCK_BASE)
	    return b;
	  else
	    return l;
	}
    }

  return 0;
}

void
nvWrite (unsigned short *data, unsigned int len)
{
  uint off = flashutl_desc->size - NVRAM_SPACE;
  sysFlashWrite (off, (uchar *) data, len);
}

void
nvWriteChars (unsigned char *data, unsigned int len)
{
  uint off = flashutl_desc->size - NVRAM_SPACE;
  int err;

  if (flashutl_cmd->type == SFLASH)
    err = sflash_commit (sbh, cc, off, len, data);
  else				/* PFLASH */
    err = flash_write (off, data, len);

  if (err)
    DPRINT (("nvWriteChars failed\n"));
  else
    DPRINT (("nvWriteChars succeeded\n"));
}

int
sysFlashErase (uint off, unsigned int numbytes)
{
  unsigned long end = off + numbytes;
  int err = 0;

  if (flashutl_cmd->type == SFLASH)
    {
      err = sflash_commit (sbh, cc, off, numbytes, NULL);
    }
  else
    {
      while (off < end)
	{
	  err = flash_eraseblk (off);
	  if (err)
	    break;
	  off = block (off, BLOCK_LIM);
	}
    }

  if (err)
    DPRINT (("Block erase at 0x%x failed\n", off));
  else
    DPRINT (("Done\n"));

  return !err;
}

int
sysFlashWrite (uint off, uchar * src, uint numbytes)
{
  int err;

  DPRINT (("Writing 0x%x bytes to flash @0x%x ...\n", (unsigned int) numbytes,
	   off));

  if (flashutl_cmd->type == SFLASH)
    err = sflash_commit (sbh, cc, off, numbytes, src);
  else
    {
      if (!sysFlashErase (off, numbytes))
	return 0;
      err = flash_write (off, src, numbytes);
    }

  if (err)
    DPRINT (("Flash write failed\n"));
  else
    DPRINT (("Flash write succeeded\n"));

  return !err;
}

int
sysFlashRead (uint off, uchar * buf, uint numbytes)
{
  uint read, total_read = 0;

  if (flashutl_cmd->type == SFLASH)
    {
      while (numbytes)
	{
	  read = sflash_read (sbh, cc, off, numbytes, buf);
	  numbytes -= read;
	  buf += read;
	  off += read;
	  total_read += read;
	}
    }
  else
    {
      ASSERT (!(off & (flashutl_wsz - 1)));
      ASSERT (!(numbytes & (flashutl_wsz - 1)));

      while (numbytes)
	{
	  flash_writeword ((unsigned long) buf,
			   flash_readword (FLASH_ADDR (off)));
	  numbytes -= flashutl_wsz;
	  buf += flashutl_wsz;
	  off += flashutl_wsz;
	  total_read += flashutl_wsz;
	}
    }

  return (total_read);
}