/****************************************************************************
 * drivers/mtd/mtd_onfi.c
 *
 *   Copyright (c) 2010, Atmel Corporation
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the names NuttX nor Atmel nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <string.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>

#include <nuttx/mtd/nand_model.h>
#include <nuttx/mtd/onfi.h>

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

/* NAND status bit mask */

#define STATUS_BIT_0             0x01
#define STATUS_BIT_1             0x02
#define STATUS_BIT_5             0x20
#define STATUS_BIT_6             0x40

#define NAND_MFR_MICRON          0x2c

/* Nand flash commands */

#define NAND_CMD_RESET           0xff
#define NAND_CMD_READ0           0x00
#define NAND_CMD_READID          0x90
#define NAND_CMD_STATUS          0x70
#define NAND_CMD_READ_PARAM_PAGE 0xec
#define NAND_CMD_SET_FEATURE     0xef

#define EBICSA_EBI_DBPDC         (1 << 9)
#define EBICSA_NAND_D0_ON_D16    (1 << 24)

/* Misc. definitions */

#define MAX_READ_STATUS_COUNT    100000 /* Read status timeout */
#define ONFI_PARAM_TABLE_SIZE    116    /* Not all 256 bytes are useful */

/* NAND access macros */

#define WRITE_NAND_COMMAND(d,c) \
  do { \
    *(volatile uint8_t *)((uintptr_t)(c)) = (uint8_t)(d); \
  } while (0)

#define WRITE_NAND_ADDRESS(d,b) \
  do { \
    *(volatile uint8_t *)((uintptr_t)(b)) = (uint8_t)(d); \
  } while (0)

#define READ_NAND(a) \
  ((*(volatile uint8_t *)(uintptr_t)a))

#define WRITE_NAND(d,a) \
  do { \
    *(volatile uint8_t *)((uintptr_t)a) = (uint8_t)d; \
  } while (0)

/****************************************************************************
 * Private Functions
 ****************************************************************************/

/****************************************************************************
 * Name: onfi_readstatus
 *
 * Description:
 *   This function Reads the status register of the NAND device by issuing a
 *   0x70 command.
 *
 * Input Parameters:
 *   cmdaddr  - NAND command address base
 *   dataaddr - NAND data address
 *
 * Returned Value:
 *   OK        : The function completed operation successfully
 *  -EIO       : The function dif not complete operation successfully
 *  -ETIMEDOUT : A time out occurred before the operation completed
 *
 ****************************************************************************/

static int onfi_readstatus(uintptr_t cmdaddr, uintptr_t dataaddr)
{
  uint32_t timeout;
  uint8_t status;

  /* Issue command */

  WRITE_NAND_COMMAND(NAND_CMD_STATUS, cmdaddr);
  timeout = 0;

  while (timeout < MAX_READ_STATUS_COUNT)
    {
      /* Read status byte */

      status = READ_NAND(dataaddr);

      /* Check status. If status bit 6 = 1 device is ready */

      if ((status & STATUS_BIT_6) == STATUS_BIT_6)
        {
          /* If status bit 0 = 0 the last operation was successful */

          if ((status & STATUS_BIT_0) == 0)
            {
              return OK;
            }
          else
            {
              return -EIO;
            }
        }

      timeout++;
    }

  return -ETIMEDOUT;
}

/****************************************************************************
 * Name: onfi_have_embeddedecc
 *
 * Description:
 *   This function check if the Nandflash has an embedded ECC controller.
 *
 * Input Parameters:
 *   onfi  - An initialized ONFI data structure.
 *
 * Returned Value:
 *   True  - Internal ECC supported
 *   False - Internal ECC not supported.
 *
 ****************************************************************************/

#ifdef CONFIG_MTD_NAND_EMBEDDEDECC
bool onfi_have_embeddedecc(FAR const struct onfi_pgparam_s *onfi)
{
  /* Check if the Nandflash has an embedded ECC controller.  Known memories
   * with this feature:
   *
   * - Manufacturer ID = 0x2c (Micron)
   * - Number of bits ECC = 0x04 (4-bit ECC means process 34nm)
   * - device size = 1Gb or 2Gb or 4Gb (Number of data bytes per page x
   *   Number of pages per block x Number of blocks per unit)
   */

  return ((onfi->manufacturer & NAND_MFR_MICRON) == NAND_MFR_MICRON &&
           onfi->eccsize == 4 &&
          (onfi->model == '1' || onfi->model == '2' || onfi->model == '4'));
}
#endif

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: onfi_compatible
 *
 * Description:
 *   This function read an the ONFI signature at address of 20h to detect
 *   if the device is ONFI compatible.
 *
 * Input Parameters:
 *   cmdaddr  - NAND command address base
 *   addraddr - NAND address address base
 *   dataaddr - NAND data address
 *
 * Returned Value:
 *   True if ONFI compatible
 *
 ****************************************************************************/

bool onfi_compatible(uintptr_t cmdaddr, uintptr_t addraddr,
                     uintptr_t dataaddr)
{
  uint8_t parmtab[ONFI_PARAM_TABLE_SIZE];

  /* Check if the Nandflash is ONFI compliant */

  WRITE_NAND_COMMAND(NAND_CMD_READID, cmdaddr);
  WRITE_NAND_ADDRESS(0x20, addraddr);

  parmtab[0] = READ_NAND(dataaddr);
  parmtab[1] = READ_NAND(dataaddr);
  parmtab[2] = READ_NAND(dataaddr);
  parmtab[3] = READ_NAND(dataaddr);

  return
      (parmtab[0] == 'O' && parmtab[1] == 'N' &&
      parmtab[2] == 'F' && parmtab[3] == 'I');
}

/****************************************************************************
 * Name: onfi_read
 *
 * Description:
 *   If the addresses refer to a compatible ONFI device, then read the ONFI
 *   parameters from the FLASH into the user provided data staructure.
 *
 * Input Parameters:
 *   cmdaddr  - NAND command address base
 *   addraddr - NAND address address base
 *   dataaddr - NAND data address
 *   onfi     - The ONFI data structure to populate.
 *
 * Returned Value:
 *   OK is returned on success and the ONFI data structure is initialized
 *   with NAND data.  A negated errno value is returned in the event of an
 *   error.
 *
 ****************************************************************************/

int onfi_read(uintptr_t cmdaddr, uintptr_t addraddr, uintptr_t dataaddr,
              FAR struct onfi_pgparam_s *onfi)
{
  uint8_t parmtab[ONFI_PARAM_TABLE_SIZE];
  int i;

  finfo("cmdaddr=%08x addraddr=%08x dataaddr=%08x\n",
        (int)cmdaddr, (int)addraddr, (int)dataaddr);

  if (!onfi_compatible(cmdaddr, addraddr, dataaddr))
    {
      ferr("ERROR: No ONFI compatible device detected\n");
      return -ENODEV;
    }

  /* Initialize the ONFI parameter table */

  memset(parmtab, 0xff, ONFI_PARAM_TABLE_SIZE);

  /* Perform Read Parameter Page command */

  WRITE_NAND_COMMAND(NAND_CMD_READ_PARAM_PAGE, cmdaddr);
  WRITE_NAND_ADDRESS(0x0, addraddr);

  /* Wait NF ready */

  onfi_readstatus(cmdaddr, dataaddr);

  /* Re-enable data output mode required after Read Status command */

  WRITE_NAND_COMMAND(NAND_CMD_READ0, cmdaddr);

  /* Read the parameter table */

  for (i = 0; i < ONFI_PARAM_TABLE_SIZE; i++)
    {
      parmtab[i] = READ_NAND(dataaddr);
    }

  for (i = 0; i < ONFI_PARAM_TABLE_SIZE; i++)
    {
      if (parmtab[i] != 0xff)
        {
          break;
        }
    }

  if (i == ONFI_PARAM_TABLE_SIZE)
    {
      ferr("ERROR: Failed to read ONFI parameter table\n");
      return -EIO;
    }

  /* JEDEC manufacturer ID */

  onfi->manufacturer = *(FAR uint8_t *)(parmtab + 64);

  /* Bus width */

  onfi->buswidth = (*(FAR uint8_t *)(parmtab + 6)) & 0x01;

  /* Get number of data bytes per page (bytes 80-83 in the param table) */

  onfi->pagesize =  *(FAR uint32_t *)(FAR void *)(parmtab + 80);

  /* Get number of spare bytes per page (bytes 84-85 in the param table) */

  onfi->sparesize =  *(FAR uint16_t *)(FAR void *)(parmtab + 84);

  /* Number of pages per block. */

  onfi->pagesperblock = *(FAR uint32_t *)(FAR void *)(parmtab + 92);

  /* Number of blocks per logical unit (LUN). */

  onfi->blocksperlun = *(FAR uint32_t *)(FAR void *)(parmtab + 96);

  /* Number of logical units. */

  onfi->luns = *(FAR uint8_t *)(parmtab + 100);

  /* Number of bits of ECC correction */

  onfi->eccsize = *(FAR uint8_t *)(parmtab + 112);

  /* Device model */

  onfi->model = *(FAR uint8_t *)(parmtab + 49);

  finfo("Returning:\n");
  finfo("  manufacturer:  0x%02x\n",      onfi->manufacturer);
  finfo("  buswidth:      %d\n",          onfi->buswidth);
  finfo("  luns:          %d\n",          onfi->luns);
  finfo("  eccsize:       %d\n",          onfi->eccsize);
  finfo("  model:         0x%02x\n",      onfi->model);
  finfo("  sparesize:     %d\n",          onfi->sparesize);
  finfo("  pagesperblock: %d\n",          onfi->pagesperblock);
  finfo("  blocksperlun:  %d\n",          onfi->blocksperlun);
  finfo("  pagesize:      %" PRId32 "\n", onfi->pagesize);
  return OK;
}

/****************************************************************************
 * Name: onfi_embeddedecc
 *
 * Description:
 *   Enable or disable the NAND's embedded ECC controller.
 *
 * Input Parameters:
 *   onfi     - An initialized ONFI data structure.
 *   cmdaddr  - NAND command address base
 *   addraddr - NAND address address base
 *   dataaddr - NAND data address
 *   enable - True: enabled the embedded ECC function; False: disable it
 *
 * Returned Value:
 *   True  - Internal ECC enabled or disabled successfully
 *   False - Internal ECC not supported.
 *
 ****************************************************************************/

#ifdef CONFIG_MTD_NAND_EMBEDDEDECC
bool onfi_embeddedecc(FAR const struct onfi_pgparam_s *onfi,
                      uintptr_t cmdaddr, uintptr_t addraddr,
                      uintptr_t dataaddr, bool enable)
{
  /* Does the NAND supported the embedded ECC function? */

  if (onfi_have_embeddedecc(onfi))
    {
      /* Yes... enable or disable it */

      /* Perform common setup */

      WRITE_NAND_COMMAND(NAND_CMD_SET_FEATURE, cmdaddr);
      WRITE_NAND_ADDRESS(0x90, addraddr);

      if (enable)
        {
          /* Activate the internal ECC controller */

          WRITE_NAND(0x08, dataaddr);
          WRITE_NAND(0x00, dataaddr);
          WRITE_NAND(0x00, dataaddr);
          WRITE_NAND(0x00, dataaddr);
        }
      else
        {
          /* De-activate the internal ECC controller */

          WRITE_NAND(0x00, dataaddr);
          WRITE_NAND(0x00, dataaddr);
          WRITE_NAND(0x00, dataaddr);
          WRITE_NAND(0x00, dataaddr);
        }

      return true;
    }

  return false;
}
#endif

/****************************************************************************
 * Name: onfi_ebidetect
 *
 * Description:
 *   Detect Nand connection on EBI
 *
 * Input Parameters:
 *   cmdaddr  - NAND command address base
 *   addraddr - NAND address address base
 *   dataaddr - NAND data address
 *
 * Returned Value:
 *   True if the chip is detected; false otherwise.
 *
 ****************************************************************************/

bool onfi_ebidetect(uintptr_t cmdaddr, uintptr_t addraddr,
                    uintptr_t dataaddr)
{
  uint32_t timer;
  uint8_t rc;
  bool found = false;
  uint8_t ids[4];
  uint8_t i;

  finfo("cmdaddr=%08x addraddr=%08x dataaddr=%08x\n",
        (int)cmdaddr, (int)addraddr, (int)dataaddr);

  /* Send Reset command */

  WRITE_NAND_COMMAND(NAND_CMD_RESET, cmdaddr);

  /* If a Nandflash is connected, it should answer to a read status command */

  for (timer = 0; timer < 60; timer++)
    {
      rc = onfi_readstatus(cmdaddr, dataaddr);
      if (rc == OK)
        {
          WRITE_NAND_COMMAND(NAND_CMD_READID, cmdaddr);
          WRITE_NAND_ADDRESS(0, addraddr);

          ids[0] = READ_NAND(dataaddr);
          ids[1] = READ_NAND(dataaddr);
          ids[2] = READ_NAND(dataaddr);
          ids[3] = READ_NAND(dataaddr);

          for (i = 0; i < NAND_NMODELS ; i++)
            {
              if (g_nandmodels[i].devid == ids[1])
                {
                  found = true;
                  break;
                }
            }

          break;
        }
    }

  if (!found)
    {
      if (onfi_compatible(cmdaddr, addraddr, dataaddr))
        {
          /* Report true if it is an ONFI device that is not in device
           * list (perhaps it is a new device that is ONFI campatible
           */

          found = true;
        }
    }

  return found;
}