flash_nor_ram.c

Flash的驱动程序。包括市面上常见的Nor Flash和Nand Flash.基本上所有的Flash只需要简单修改就可以移植到其他应用。

  
  /*====*====*====*====*====*====*====*====*====*====*====*====*====*====*====*
  
                     E M B E D D E D   F I L E   S Y S T E M
  
  
  GENERAL DESCRIPTION
    File System NOR Device Driver Simulation over P/SRAM
  
  Copyright (c) 1999 - 2006 by QUALCOMM Incorporated. All Rights Reserved.
  *====*====*====*====*====*====*====*====*====*====*====*====*====*====*====*/
  
  /*===========================================================================
  
                          EDIT HISTORY FOR MODULE
  
  $Header: //depot/asic/msmshared/drivers/flash/MSM_FLASH.01.04/flash_nor_ram.c#3 $ $DateTime: 2006/05/26 10:49:40 $ $Author: dhamimp $
    
     
  when       who     what, where, why
  --------   ---     ----------------------------------------------------------
  10/11/05   dp      RAM driver to simulate a NOR Flash
  
  ===========================================================================*/
  
  /*===========================================================================
  
                       INCLUDE FILES FOR MODULE
  
  ===========================================================================*/
#include "customer.h"

#include "comdef.h"
#include <memory.h>
#include "flash_nor_device.h"
#include "flash_nor_msm.h"
#include "clk.h"
#include "flash_msg.h"
  
  
  /* Forward function prototypes */
LOCAL flash_status fsi_ram_configure (fsi_nor_device *nor_device, flash_ptr_type eraseaddr);
LOCAL flash_status fsi_ram_write (byte *buffer, flash_ptr_type baseaddr, dword offset, dword count);
LOCAL flash_status fsi_ram_erase (flash_ptr_type baseaddr, dword offset);
LOCAL flash_status fsi_ram_erase_status (flash_ptr_type eraseaddr);
LOCAL flash_status fsi_ram_suspend (flash_ptr_type eraseaddr);
LOCAL flash_status fsi_ram_resume (flash_ptr_type eraseaddr);

LOCAL struct fsi_dev_ops flash_ram_op_functions =
{
  fsi_ram_configure,                         /* Configuration of hardware */
  fs_nor_device_worded_read,                 /* Read operation. */
  fsi_ram_write,                             /* Write for Spansion. */
  fsi_ram_erase,                             /* Erase for Spansion. */
  fsi_ram_erase_status,                      /* Status for Spansion. */
  fsi_ram_suspend,
  fsi_ram_resume,
};
  
/* Device information for each operation. */
LOCAL fsi_nor_device RAM_NOR = {
  "NOR_ON_RAM",
  0,                      /* # of codes to match */
  {0,0,0,0},              /* Manufacture codes. */
  0,
  {
    FLASH_NOR_EFS2_START_BYTE_OFFSET,  /* Byte offset to EFS2 area. */
    (FLASH_NOR_EFS2_END_BYTE_OFFSET - FLASH_NOR_EFS2_START_BYTE_OFFSET) + 1,
    FLASH_NOR_EFS2_SECTOR_BYTE_SIZE,
    FLASH_NOR_EFS2_NUM_SECTORS
  },
  INIT_NOT_NEEDED,
  &flash_ram_op_functions
};

/*===========================================================================

FUNCTION FSI_RAM_ERASE

DESCRIPTION
  Initiate erase operation.

DEPENDENCIES
  fsi_target is initialized

RETURN VALUE
  FLASH_SUCCESS            -  If erase operation was successfully initiated
  FLASH_OP_NOT_COMPLETE    -  If an erase operation is already in progress 
  FLASH_FAILURE            -  If erase operation could not otherwise be started

SIDE EFFECTS
  None

===========================================================================*/
LOCAL flash_status
fsi_ram_erase (flash_ptr_type baseaddr, dword offset)
{
  volatile word *wptr;
  volatile byte *bptr;
  dword i;
  extern fsi_nor_device *nor_device;

  wptr = baseaddr + BYTE_TO_WORD_OFFSET(offset);
  bptr = (volatile byte *) wptr;
  
  for (i=0; i < nor_device->efs_info.efs_blk_bsize; i++)
  {
    bptr[i] = 0xFF;
  }

  return FLASH_SUCCESS;
}

/*===========================================================================

FUNCTION FSI_RAM_ERASE_STATUS

DESCRIPTION
  Erase status check.

DEPENDENCIES
  The device must be in the erasing state.

RETURN VALUE
  FLASH_SUCCESS               - The erase is finished, component is not in
                                read state
  FLASH_OP_NOT_COMPLETE       - The erase is still happening.
  FLASH_FAILURE               - Something went wrong with the erase.

SIDE EFFECTS
  None

===========================================================================*/
LOCAL flash_status
fsi_ram_erase_status (flash_ptr_type eraseaddr )
{
  return FLASH_SUCCESS;
}

/*===========================================================================

FUNCTION FSI_RAM_WRITE

DESCRIPTION
  Write a block of bytes.

DEPENDENCIES
  The device must not be in erasing state.

RETURN VALUE
  FLASH_SUCCESS      -  If write completed normally
  FLASH_FAILURE      -  If write operation failed

SIDE EFFECTS
  None

===========================================================================*/
LOCAL flash_status
fsi_ram_write (byte *buffer,
               flash_ptr_type baseaddr,
               dword offset,
               dword count)
{
  volatile byte *part_base, *bptr;
  volatile word *wptr, *check_ptr;
  word value;
  word tmp;


  /* Base address of operation. */
  part_base = ((volatile byte *) baseaddr + offset);
  
  check_ptr = (volatile word *) ((dword) part_base & ~1);

  /* Determine if the block is aligned or not. */
  if (((dword) buffer & 1) == 0
      && (offset & 1) == 0
      && (count & 1) == 0)
  {
    /* Do word operations. */
    wptr = (volatile word *) part_base;

    /* Since we're already aligned, we could compare with 0, but the
       1 will be needed for future optimizations. */
    while (count > 1)
    {
      value = *((word *) buffer);
      *wptr = value;
      buffer += 2;
      wptr   += 1;
      count  -= 2;
    }
  }
  else
  {
    /* Do byte operations. */
    bptr = part_base;

    while (count > 0)
    {
      value = *buffer;

      /* The command accesses need to be word oriented or the data
         will be placed on the wrong data lines.  Compute a word
         pointer from the byte pointer that is always at an even
         address. */
      wptr = ((volatile word *) ((dword) bptr & ~1));

      /* Get old value. */
      tmp = *wptr;
      /* Assumes little endian. */
      if (((dword) bptr & 1) == 0)
        value = tmp & (value | 0xFF00);
      else
        value = tmp & ((value << 8) | 0x00FF);
      *wptr = value;

      buffer += 1;
      bptr   += 1;
      count  -= 1;
    }
  }

  return FLASH_SUCCESS;
}


/*======================================================================
FUNCTION FSI_RAM_SUSPEND

DESCRIPTION
  Suspend an erase operation.

DEPENDENCIES

RETURN VALUE
  FLASH_SUCCESS             - The erase has completed.
  FLASH_OP_NOT_COMPLETE     - The erase was suspended, reads may be done.
  FLASH_FAILURE             - The suspend failed, or an erase was not in
                          progress.

SIDE EFFECTS
  None
========================================================================*/
LOCAL flash_status
fsi_ram_suspend (flash_ptr_type eraseaddr)
{
  return FLASH_SUCCESS;
}

/*===========================================================================
FUNCTION FSI_RAM_RESUME

DESCRIPTION
  Resume a suspended erase.

DEPENDENCIES

RETURN VALUE
  FLASH_SUCCESS             - The erase has been resumed.
  FLASH_FAILURE             - An error occurred.

SIDE EFFECTS
  None
===========================================================================*/
LOCAL flash_status
fsi_ram_resume (flash_ptr_type eraseaddr)
{
  return FLASH_SUCCESS;
}


/*===========================================================================
FUNCTION FSI_RAM_CONFIGURE

DESCRIPTION
  Do any necessary initializtion.

DEPENDENCIES
  
RETURN VALUE
  FLASH_SUCCESS             - Success
  FLASH_FAILURE             - An error occurred.

SIDE EFFECTS
  None
===========================================================================*/

LOCAL flash_status
fsi_ram_configure (fsi_nor_device * nor_device, flash_ptr_type baseaddr)
{
    /* just a stub for devices that need no configuration */
    return FLASH_SUCCESS;
}